首页   |  中国科学院
当前位置: 首页>SCI收录论文
2018年
作者: 来源 : 时间:2020-01-06 字体<    >

第 1 条,共 322 条
标题: 10 Gbps DPSK transmission over free-space link in the mid-infrared
作者: Su, YL (Su, Yulong); Wang, W (Wang, Wei); Hu, XH (Hu, Xiaohong); Hu, H (Hu, Hui); Huang, XN (Huang, Xinning); Wang, YS (Wang, Yishan); Si, JH (Si, Jinhai); Xie, XP (Xie, Xiaoping); Han, B (Han, Biao); Feng, H (Feng, Huan); Hao, Q (Hao, Qiang); Zhu, GS (Zhu, Guoshen); Duan, T (Duan, Tao); Zhao, W (Zhao, Wei)
来源出版物: OPTICS EXPRESS 卷: 26 期: 26 页: 34515-34528 DOI: 10.1364/OE.26.034515 出版年: DEC 24 2018
摘要: We experimentally demonstrate the implementation of 10 Gbps high-speed mid-infrared (MIR) free-space optical (FSO) communication, by means of our developed robust high-speed MIR transmitter and receiver modules. Such modules can enable frequency down- and up-conversion between 1550 nm and 3594 nm based on difference frequency generation (DFG) in MgO-doped periodically poled LiNbO3 (MgO: PPLN). The MIR transmitter generates 5.34 dBm power at 3594 nm for input powers of 33 dBm at 1550 mn and 37 dBm at 1083 nm. The MIR receiver regenerates -24.5 dBm power at 1550 nm for input powers of -1.2 dBm at 3594 nm and 36.7 dBm at 1083 nm. The eye diagram of regenerated 1550 nm signal is clear, and both for the on-off keying (OOK) and differential phase shift keying (DPSK) modulation, the power penalties compared with back to back (BTB) signals are lower than 3.5 dB measured at bit error ratio (BER) of 1E-6. According to our analyses, the system supports variable data rate, wavelength, and modulation format. Furthermore, the optical and electrical components are well integrated and fixed in MIR transmitter and receiver modules, which exhibit long-term stability and can be applied to field experiments. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000454149000088
PubMed ID: 30650874
ISSN: 1094-4087
________________________________________
第 2 条,共 322 条
标题: Photoelectron backscattering in the microchannel plate photomultiplier tube
作者: Chen, P (Chen, Ping); Tian, JS (Tian, Jinshou); Guo, LH (Guo, Lehui); Wei, YL (Wei, Yonglin); Liu, HL (Liu, Hulin); Sai, XF (Sai, Xiaofeng); Wang, X (Wang, Xing); Lu, Y (Lu, Yu); Wang, C (Wang, Chao); Wang, JF (Wang, Junfeng); He, K (He, Kai); Tian, LP (Tian, Liping); Xin, LW (Xin, Liwei); Guo, HT (Guo, Haitao)
来源出版物: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 卷: 912 特刊: SI 页: 112-114 DOI:10.1016/j.nima.2017.10.081 出版年: DEC 21 2018
摘要: The late pulse occurring in photomultiplier tubes (PMTS) is attributed to photoelectron backscattering. The small effective open area of microchannel plates (MCPs) increases the probability of photoelectrons bouncing on the front surface of MCPs and aggravates late pulses. In this work, a three-dimensional MCP-PMT model is developed in CST particle studio, a powerful electromagnetic field simulation program, to evaluate the effects of secondary emission yield (SEY) property of the MCP input facet and electric field on the photoelectron backscattering. Timing properties and the number of collected electrons are extracted without smearing due to electronic noise and finite pulse width. Results predict that the collection efficiency (CE) and the time performance can be improved by coating the MCP Nickel-Chromium input electrode with a high SEY material and operating in a proper photocathode-MCP bias voltage. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000453717200030
会议名称: 8th International Conference on New Developments in Photodetection (NDIP)
会议日期: JUL, 2017
会议地点: Tours, FRANCE
会议赞助商: CEA, DRF, Inst Res Fundamental Laws Universe, CEA Tech LIST, CNRS, Inst Natl Physique Nucl Physique Particules, Univ Paris Diderot, Lab AstroParticule Cosmologie, CNRS, Ecole Polytechnique, Lab Physique Interfaces Couches Minces
ISSN: 0168-9002
eISSN: 1872-9576
________________________________________
第 3 条,共 322 条
标题: Design of the large area MCP-PMT
作者: Chen, P (Chen, Ping); Tian, JS (Tian, Jinshou); Zhao, TC (Zhao, Tianchi); Liu, SL (Liu, Shulin); Qian, S (Qian, Sen); Sun, JN (Sun, Jianning); Si, SG (Si, Shuguang); Liu, HL (Liu, Hulin); Wei, YL (Wei, Yonglin); Sai, XF (Sai, Xiaofeng); Guo, LH (Guo, Lehui); Wang, X (Wang, Xing); Lu, Y (Lu, Yu); Wang, C (Wang, Chao); Wang, JF (Wang, Junfeng); He, K (He, Kai); Pei, CQ (Pei, Chengquan); Tian, LP (Tian, Liping); Xin, LW (Xin, Liwei)
来源出版物: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 卷: 912 特刊: SI 页: 163-166 DOI:10.1016/j.nima.2017.11.012 出版年: DEC 21 2018
摘要: This paper describes the design of the 8-inch and 20-inch photomultiplier tubes based on microchannel plates (MCP-PMT). In the large area MCP-PMT, the small MCPs replace the bulky dynode chain in the traditional large PMTs. Photoelectrons are electrostatically focused on MCPs. The MCP assembly, focusing electrodes as well as the supply voltages are carefully optimized to achieve a wide photosensitive area, high photon detection efficiency and good timing resolution. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000453717200042
会议名称: 8th International Conference on New Developments in Photodetection (NDIP)
会议日期: JUL, 2017
会议地点: Tours, FRANCE
会议赞助商: CEA, DRF, Inst Res Fundamental Laws Universe, CEA Tech LIST, CNRS, Inst Natl Physique Nucl Physique Particules, Univ Paris Diderot, Lab AstroParticule Cosmologie, CNRS, Ecole Polytechnique, Lab Physique Interfaces Couches Minces
ISSN: 0168-9002
eISSN: 1872-9576
________________________________________
第 4 条,共 322 条
标题: Coherent synthesis of ultrashort pulses based on balanced optical cross-correlator
作者: Huang, P (Huang Pei); Fang, SB (Fang Shao-Bo); Huang, HD (Huang Hang-Dong); Hou, X (Hou Xun); Wei, ZY (Wei Zhi-Yi)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 24 文献号: 244204 DOI: 10.7498/aps.67.20181851 出版年: DEC 20 2018
摘要: Coherent synthesis of laser pulses is a major trend in the generation of ultrafast pulse field. There is no good way to compensate for the whole spectrum when the spectrum of ultrashort pulses is wide enough to reach an octave, so it is difficult to realize a sub-cycle pulse in a single-path laser system even if the spectrum range is wide enough. In this paper, 0.8 mJ, 30 fs laser pulses at 1 kHz repetition rate with 790 nm center wavelength from a Ti:sapphire chirped pulse amplifier (CPA) system are focused into hollow fiber with an inner diameter of 250 mu m and a length of 1 m to produce an octave-spanning white-light supercontinuum (450-950 nm). Using this supercontinuum, we conduct two sets of comparative experiments. 1) We split the supercontinuum into two pulses with different spectrum ranges (450-750 nm and 650-1000 nm) by a dichroic mirror (HR, 500-700 nm; HT, 700-1000 nm), and we compress the two pulses by the double-chirped mirrors and wedge pairs to generate two few-cycle pulses: the long and short wavelength yielding pulses are 7.9 fs and 6.1 fs, respectively. Then we coherently synthesize two pulses by using another dichroic mirror, and controlling the relative time delay between the two pulses, and thus we synthesize a pulse of 4.1 fs. 2) We directly compress the supercontinuum by the double-chirped mirrors and wedge pairs, and obtain an optimization result of 5.3 fs, of which the pulse duration is wider than that in experiment 1. In these comparative experiments, the advantage of coherent synthesis for shorter pulse duration is preliminarily verified. Besides, the balanced optical cross-correlator technique is used to lock the relative time delay between two pulses. The root-mean-square value of relative time delay drift is less than 80 as in the case with feedback control loop, which ensures the stability of coherent synthesis system. This scheme can be adopted to accurately compensate for the dispersion and obtain the sub-cycle synthesized pulse, which is useful for generating the high harmonic and atto-second pulse.
入藏号: WOS:000455406800014
ISSN: 1000-3290
________________________________________
第 5 条,共 322 条
标题: Optofluidic twin-core hollow fiber interferometer for label-free sensing of the streptavidin-biotin binding
作者: Yang, XH (Yang, Xinghua); Yu, WT (Yu, Wenting); Liu, ZH (Liu, Zhihai); Yang, J (Yang, Jun); Zhang, Y (Zhang, Yu); Kong, DP (Kong, Depeng); Long, QL (Long, Qunlong); Yuan, TT (Yuan, Tingting); Cao, JM (Cao, Jiaming); Yuan, LB (Yuan, Libo); Oh, K (Oh, Kyunghwan)
来源出版物: SENSORS AND ACTUATORS B-CHEMICAL 卷: 277 页: 353-359 DOI: 10.1016/j.snb.2018.09.032 出版年: DEC 20 2018
摘要: We proposed and experimentally demonstrated an optofluidic biosensor using a twin-core hollow optical fiber (TC-HOF) interferometer for label-free sensing of the streptavidin-biotin binding. The TC-HOF had a central hole and two cores were imbedded near its circumference. The central hole functioned as a microfluidic channel where the liquid was flown. One of the cores was suspended at the inner surface of the hole and served as sensing arm while the other core embedded in the cladding as the reference arm, which formed an integrated all-fiber Mach-Zehnder interferometer (MZI). Both ends of TC-HOF were serially spliced to multimode fiber-single mode fiber assembly, whose lateral positions were adjusted to maximize the interference visibility. Before the surface functionalization, the pristine TC-HOF MZI showed the RI sensitivity of 2577 nm/RIU. The suspended core's surface was chemically modified with streptavidin and biotin solutions were injected through micro-HOles in TC-HOF. Through the specific binding reaction between biotin and streptavidin, the effective refractive index (RI) around the sensing arm was modulated, which was detected by the spectral shifts in the interference patterns. The proposed sensor showed an excellent linear response to the biotin concentration in the range of 0.01-0.1 mg/mL and the net detection sensitivity of biotin was 16.9 nm/(mg/mL), which was achieved in a label-free manner. This device can be further applied to sensing and monitoring of the biochemical binding of biotin with various biomolecules such as cells, antigens, antibodies, and DNA in real-time and in situ.
入藏号: WOS:000453066700044
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yang, jun         G-4446-2014         0000-0002-6805-4289

ISSN: 0925-4005
________________________________________
第 6 条,共 322 条
标题: A CNN-RNN architecture for multi-label weather recognition
作者: Zhao, B (Zhao, Bin); Li, XL (Li, Xuelong); Lu, XQ (Lu, Xiaoqiang); Wang, ZG (Wang, Zhigang)
来源出版物: NEUROCOMPUTING 卷: 322 页: 47-57 DOI: 10.1016/j.neucom.2018.09.048 出版年: DEC 17 2018
摘要: Weather Recognition plays an important role in our daily lives and many computer vision applications. However, recognizing the weather conditions from a single image remains challenging and has not been studied thoroughly. Generally, most previous works treat weather recognition as a single-label classification task, namely, determining whether an image belongs to a specific weather class or not. This treatment is not always appropriate, since more than one weather conditions may appear simultaneously in a single image. To address this problem, we make the first attempt to view weather recognition as a multi-label classification task, i.e., assigning an image more than one labels according to the displayed weather conditions. Specifically, a CNN-RNN based multi-label classification approach is proposed in this paper. The convolutional neural network (CNN) is extended with a channel-wise attention model to extract the most correlated visual features. The Recurrent Neural Network (RNN) further processes the features and excavates the dependencies among weather classes. Finally, the weather labels are predicted step by step. Besides, we construct two datasets for the weather recognition task and explore the relationships among different weather conditions. Experimental results demonstrate the superiority and effectiveness of the proposed approach. The new constructed datasets will be available at https://github.com/wzgwzg/Multi-Label-Weather-Recognition. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000447624800005
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 7 条,共 322 条
标题: A 20 W, Less-Than-1-kHz Linewidth Linearly Polarized All-Fiber Laser
作者: Xue, MY (Xue, Mingyuan); Gao, CX (Gao, Cunxiao); Niu, LQ (Niu, Linquan); Zhu, SL (Zhu, Shaolan); Sun, CD (Sun, Chuandong); Zhang, J (Zhang, Jian); He, HD (He, Haodong)
来源出版物: APPLIED SCIENCES-BASEL 卷: 8 期: 12 文献号: 2593 DOI: 10.3390/app8122593 出版年: DEC 2018
摘要: We report a continuous-wave high-output power and narrow-linewidth all-fiber laser at 1550 nm with the master oscillator power amplifier (MOPA) configuration. An all-fiber distributed feedback seed laser was boosted by three cascaded fiber amplifiers. In the experiment, we adopted a large-mode-area (LMA) Er3+:Yb3+-co-doped polarization-maintaining fiber to increase nonlinear thresholds and avoided the broadening of the laser linewidth. A linear-polarization fiber laser with average output power of 20 W, linewidth of 0.88 kHz, and power jitter less than 2% was finally achieved.
入藏号: WOS:000455145000261
ISSN: 2076-3417
________________________________________
第 8 条,共 322 条
标题: Feature Fusion Information Statistics for feature matching in cluttered scenes
作者: Zhou, W (Zhou, Wei); Ma, CW (Ma, Caiwen); Liao, SH (Liao, Shenghui); Shi, JJ (Shi, Jinjing); Yao, T (Yao, Tong); Chang, P (Chang, Peng); Kuijper, A (Kuijper, Arjan)
来源出版物: COMPUTERS & GRAPHICS-UK 卷: 77 页: 50-64 DOI: 10.1016/j.cag.2018.09.012 出版年: DEC 2018
摘要: Object recognizing in cluttered scenes remains a largely unsolved problem, especially when applying feature matching to cluttered scenes there are many feature mismatches between the scenes and models. We propose our Feature Fusion Information Statistics (FFIS) as the calculation framework for extracting salient information from a Local Surface Patch (LSP) by a Local Reference Frame (LRF). Our LRF is defined on each LSP by projecting the scatter matrix's eigenvectors to a plane which is perpendicular to the normal of the LSP. Based on this, our FFIS descriptor of each LSP is calculated, for which we use the combined distribution of mesh and point information in a local domain. Finally, we evaluate the speed, robustness and descriptiveness of our FFIS with the state-of-the-art methods on several public benchmarks. Our experiments show that our FFIS is fast and obtains a more reliable matching rate than other approaches in cluttered situations. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000455063200009
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Kuijper, Arjan         A-7814-2012         0000-0002-6413-0061
Zhou, Wei                  0000-0001-8328-3736

ISSN: 0097-8493
eISSN: 1873-7684
________________________________________
第 9 条,共 322 条
标题: High Resolution and Fast Processing of Spectral Reconstruction in Fourier Transform Imaging Spectroscopy
作者: Zhang, WK (Zhang, Weikang); Wen, DS (Wen, Desheng); Song, ZX (Song, Zongxi); Wei, X (Wei, Xin); Liu, G (Liu, Gang); Li, ZX (Li, Zhixin)
来源出版物: SENSORS 卷: 18 期: 12 文献号: 4159 DOI: 10.3390/s18124159 出版年: DEC 2018
摘要: High-resolution spectrum estimation has continually attracted great attention in spectrum reconstruction based on Fourier transform imaging spectroscopy (FTIS). In this paper, a parallel solution for interference data processing using high-resolution spectrum estimation is proposed to reconstruct the spectrum in a fast high-resolution way. In batch processing, we use high-performance parallel-computing on the graphics processing unit (GPU) for higher efficiency and lower operation time. In addition, a parallel processing mechanism is designed for our parallel algorithm to obtain higher performance. At the same time, other solving algorithms for the modern spectrum estimation model are introduced for discussion and comparison. We compare traditional high-resolution solving algorithms running on the central processing unit (CPU) and the parallel algorithm on the GPU for processing the interferogram. The experimental results illustrate that runtime is reduced by about 70% using our parallel solution, and the GPU has a great advantage in processing large data and accelerating applications.
入藏号: WOS:000454817100078
PubMed ID: 30486414
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zhang, Weikang                  0000-0003-2279-3294
Li, Zhixin                  0000-0002-5462-4084

ISSN: 1424-8220
________________________________________
第 10 条,共 322 条
标题: Enhanced four-wave mixing in waveguides integrated with graphene oxide
作者: Yang, YY (Yang, Yunyi); Wu, JY (Wu, Jiayang); Xu, XY (Xu, Xingyuan); Liang, Y (Liang, Yao); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Jia, BH (Jia, Baohua); Moss, DJ (Moss, David J.)
来源出版物: APL PHOTONICS 卷: 3 期: 12 文献号: 120803 DOI: 10.1063/1.5045509 出版年: DEC 2018
摘要: We demonstrate enhanced four-wave mixing (FWM) in doped silica waveguides integrated with graphene oxide (GO) layers. Owing to strong mode overlap between the integrated waveguides and GO films that have a high Kerr nonlinearity and low loss, the FWM efficiency of the hybrid integrated waveguides is significantly improved. We perform FWM measurements for different pump powers, wavelength detuning, GO coating lengths, and number of GO layers. Our experimental results show good agreement with theory, achieving up to similar to 9.5-dB enhancement in the FWM conversion efficiency for a 1.5-cm-long waveguide integrated with 2 layers of GO. We show theoretically that for different waveguide geometries an enhancement in FWM efficiency of similar to 20 dB can be obtained in the doped silica waveguides and more than 30 dB in silicon nanowires and slot waveguides. This demonstrates the effectiveness of introducing GO films into integrated photonic devices in order to enhance the performance of nonlinear optical processes. (C) 2018 Author(s).
入藏号: WOS:000454248200004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X

ISSN: 2378-0967
________________________________________
第 11 条,共 322 条
标题: Fast and Flexible Large Graph Embedding Based on Anchors
作者: Yu, WZ (Yu, Weizhong); Nie, FP (Nie, Feiping); Wang, F (Wang, Fei); Wang, R (Wang, Rong); Li, XL (Li, Xuelong)
来源出版物: IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING 卷: 12 期: 6 页: 1465-1475 DOI: 10.1109/JSTSP.2018.2873985 出版年: DEC 2018
摘要: Dimensionality reduction is one of the most fundamental topic in machine learning. A range of methods focus on dimensionality reduction have been proposed in various areas. Among the unsupervised dimensionality reduction methods, graph-based dimensionality reduction has begun to draw more and more attention due to its effectiveness. However, most existing graph-based methods have high computation complexity, which is not applicable to large-scale problems. To solve this problem, an unsupervised graph-based dimensionality reduction method called fast and flexible large graph embedding (FFLGE) based on anchors is proposed. FFLGE uses an anchor-based strategy to construct an anchor-based graph and design similarity matrix and then perform the dimensionality reduction efficiently. The computational complexity of the proposed FFLGE reduces to O(ndm), where n is the number of samples, d is the number of dimensions and m is the number of anchors. Furthermore, it is interesting to note that locality preserving projection and principal component analysis are two special cases of FFLGE. In the end, the experiments based on several publicly large-scale datasets proves the effectiveness and efficiency of the method proposed.
入藏号: WOS:000454221700027
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Nie, Feiping         B-3039-2012         
Li, Xuelong         Z-3785-2019         
Wang, Rong                  0000-0001-9240-6726
Nie, Feiping                  0000-0002-0871-6519

ISSN: 1932-4553
eISSN: 1941-0484
________________________________________
第 12 条,共 322 条
标题: Biomimetic Anti-adhesive Surface Micro-structures of Electrosurgical Knife Fabricated by Fibre Laser
作者: Li, C (Li, Chen); Yang, LJ (Yang, Li-jun); Yan, CC (Yan, Cheng-cheng); Chen, W (Chen, Wei); Cheng, GH (Cheng, Guang-hua)
来源出版物: JOURNAL OF LASER MICRO NANOENGINEERING 卷: 13 期: 3 页: 309-313 DOI: 10.2961/jlmn.2018.03.0028 出版年: DEC 2018
摘要: Electrosurgical knife is the most common invasive surgical instrument in a cutting and hemostasis process, which easily leads the overheated tissues to pyrolysis, eschar and adhesion on the knife surface. In order to minimize the adhesion of the overheated tissues, we investigated and fabricated the surface micro-structures on the blade by fiber laser inspired by shark's skin. The wettability of the blade surfaces with different bionic shark skins were measured by the contact angles, revealing the surface wettability effect. Frictional coefficients between the blade surfaces with different bionic shark skins and pork liver tissues are respectively measured by friction test machine. After cutting the pork liver, the adhesive tissue mass on the electrosurgical knives are weighed to study the anti-adhesion. The relationship between adhesive mass, wettability and frictional coefficients on the bionic shark skins are analyzed in the orthogonal experimental method. The experimental results show that the bionic shark skin on the blades can effectively reduce the adhesive tissues.
入藏号: WOS:000453263900028
ISSN: 1880-0688
________________________________________
第 13 条,共 322 条
标题: Dynamical behavior of self-accelerating beams in LiNbO3 crystal with background illumination
作者: Zhang, MZ (Zhang, Meizhi); Zhang, TY (Zhang, Tongyi); Huo, GW (Huo, Guangwen); Zha, XW (Zha, Xinwei); Hui, ZQ (Hui, Zhanqiang); Zhou, H (Zhou, Hua)
来源出版物: APPLIED PHYSICS B-LASERS AND OPTICS 卷: 124 期: 12 文献号: 236 DOI: 10.1007/s00340-018-7108-5 出版年: DEC 2018
摘要: We theoretically study the propagations and interactions of an Airy beam, soliton, and nonlinear self-accelerating beam in LiNbO3 crystal modulated by a shorter wavelength background beam. Simulations indicate that the self-accelerating beam and Airy beam can effectively propagate even in self-defocusing media, and the finite-energy Airy beam can generate bright solitons in a self-focusing medium. When two counter-shift Airy beams interact under appropriate conditions, fusion solitons, breathing solitons, and soliton pairs are generated. If we allow a photovoltaic soliton to collide with an Airy beam, X-type waves and soliton deflection occur at a specific phase shift and beam interval. Moreover, we find that the dynamics of two truncated nonlinear self-accelerating beams tend to exhibit straight propagation with attraction and repulsion in the in- and out-of-phase cases, respectively. These results are significant for applications related to optical routing and optical switches.
入藏号: WOS:000450989200002
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zhang, Meizhi         M-8269-2018         0000-0002-7182-0271

ISSN: 0946-2171
eISSN: 1432-0649
________________________________________
第 14 条,共 322 条
标题: Ultrafast camera with MHz repetition rate for 2D time-resolved fluorescence imaging of cells and tissues
作者: Ye, W (Ye, Wen); Yang, Y (Yang, Yang); Xu, P (Xu, Peng); Wang, B (Wang, Bo); Zhu, BL (Zhu, Bingli); Cao, WW (Cao, Weiwei); Bai, YL (Bai, Yonglin)
来源出版物: BASIC & CLINICAL PHARMACOLOGY & TOXICOLOGY 会议摘要: 185 卷: 124 特刊: SI 页: 116-117 增刊: 2 出版年: DEC 2018
入藏号: WOS:000452533800186
ISSN: 1742-7835
eISSN: 1742-7843
________________________________________
第 15 条,共 322 条
标题: Characterizations of a Proposed 3300-V Press-Pack IGBT Module Using Nanosilver Paste for High-Voltage Applications
作者: Feng, JJ (Feng, Jingjing); Mei, YH (Mei, Yunhui); Li, XB (Li, Xianbin); Lu, GQ (Lu, Guo-Quan)
来源出版物: IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS 卷: 6 期: 4 页: 2245-2253 DOI: 10.1109/JESTPE.2018.2820046 出版年: DEC 2018
摘要: Nanosilver paste was used in this study as a die-attachment material for 3300-V power chips to eliminate the pressure contact of a press-pack power module. The proposed insulated-gate bipolar transistor (IGBT) module was named as a sinter-pack IGBT module. We studied the effect of the assisted hydrostatic pressure, i.e., 0, 1, 3, 5, and 10 MPa, on the mechanical, thermal, and electrical performance of the as-sintered silver joints. As the pressure increased, the die-shear strength increased, and the thermal impedance decreased, as expected. The electrical properties of the assembly using the sintered silver were comparable with those of the chip with the same power rating, which proved the feasibility of the as-sintered IGBT specimens. The thermal resistance of the sinter-pack IGBT module decreased by 15.8% compared with that of the commercial press-pack one with the same power rating. The static electrical properties of the sinter-pack IGBT module were consistent with those of the commercial press-pack one, which further proved the feasibility of the sinter-pack IGBT module.
入藏号: WOS:000449092400054
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Lu, Guo-Quan                  0000-0003-3079-8589

ISSN: 2168-6777
________________________________________
第 16 条,共 322 条
标题: Shape-Preserving Object Depth Control for Stereoscopic Images
作者: Lei, JJ (Lei, Jianjun); Peng, B (Peng, Bo); Zhang, CQ (Zhang, Changqing); Mei, XG (Mei, Xuguang); Cao, XC (Cao, Xiaochun); Fan, XT (Fan, Xiaoting); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 卷: 28 期: 12 页: 3333-3344 DOI: 10.1109/TCSVT.2017.2749146 出版年: DEC 2018
摘要: In the field of 3-D technology, it is interesting as well as meaningful issue to control object depth in 3-D space. Recently, some depth control methods for stereoscopic images have been proposed, which usually employ depth map or directly process color images to implement depth control. There are two main disadvantages for these methods. First, the results of these methods usually suffer from object deformation and holes. Second, these methods are prone to cause undesired object size changing in 3-D space. To address these issues, we propose a shape-preserving object depth control method for stereoscopic images. First, a novel depth mapping model is presented for calculating the ideal coordinates of the key points in depth control, so that the shape of the object can be well preserved. Afterward, the image content-based constraints are used to further preserve the structure of the object and its background. Finally, the warping technology is introduced to deal with images optimally as well as to avoid holes. Experimental results show that the proposed method can control object depth and preserve the shape of the object effectively without sensible background distortion.
入藏号: WOS:000452429900002
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197
Peng, Bo                  0000-0002-6616-453X

ISSN: 1051-8215
eISSN: 1558-2205
________________________________________
第 17 条,共 322 条
标题: Weakly Supervised Object Detection via Object-Specific Pixel Gradient
作者: Shen, YH (Shen, Yunhang); Ji, RR (Ji, Rongrong); Wang, CH (Wang, Changhu); Li, X (Li, Xi); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 12 页: 5960-5970 DOI: 10.1109/TNNLS.2018.2816021 出版年: DEC 2018
摘要: Most existing object detection algorithms are trained based upon a set of fully annotated object regions or bounding boxes, which are typically labor-intensive. On the contrary, nowadays there is a significant amount of imagelevel annotations cheaply available on the Internet. It is hence a natural thought to explore such "weak" supervision to benefit the training of object detectors. In this paper, we propose a novel scheme to perform weakly supervised object localization, termed object-specific pixel gradient (OPG). The OPG is trained by using image-level annotations alone, which performs in an iterative manner to localize potential objects in a given image robustly and efficiently. In particular, we first extract an OPG map to reveal the contributions of individual pixels to a given object category, upon which an iterative mining scheme is further introduced to extract instances or components of this object. Moreover, a novel average and max pooling layer is introduced to improve the localization accuracy. In the task of weakly supervised object localization, the OPG achieves a state-of-the-art 44.5% top-5 error on ILSVRC 2013, which outperforms competing methods, including Oquab et al. and region-based convolutional neural networks on the Pascal VOC 2012, with gains of 2.6% and 2.3%, respectively. In the task of object detection, OPG achieves a comparable performance of 27.0% mean average precision on Pascal VOC 2007. In all experiments, the OPG only adopts the off-the-shelf pretrained CNN model, without using any object proposals. Therefore, it also significantly improves the detection speed, i.e., achieving three times faster compared with the stateof-the-art method.
入藏号: WOS:000451230100014
PubMed ID: 29993990
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xi         L-1234-2013         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 18 条,共 322 条
标题: Dynamical stochastic resonance for non-uniform illumination image enhancement
作者: Zhang, YB (Zhang, Yongbin); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu)
来源出版物: IET IMAGE PROCESSING 卷: 12 期: 12 页: 2147-2152 DOI: 10.1049/iet-ipr.2018.5634 出版年: DEC 2018
摘要: Images taken under poor illumination conditions have low contrast and dark tones. General dark image enhancement algorithms cannot effectively enhance these images without introducing over-enhancement, detail loss, and noise amplification. In this study, a simple and fast enhancement technique of non-uniform illumination images is proposed based on dynamical stochastic resonance (DSR). The low-contrast images are enhanced through the nonlinear iteration by solving monostable Langevin equation. Iteration parameters are dynamically adjusted according to the intensity distribution of the original images, which ensure the balance of visibility and naturalness in the entire areas. A threshold is defined to automatically confirm the optimal outputs. The enhanced image is obtained by fusing the DSR result, original component, and illumination compensation component. The computational time, no-reference perceptual quality assessment, and lightness order error are measured to evaluate the performance of experimental results. The subjective and objective comparison with state-of-the-art methods shows that our method performs well to enhance the non-uniform illumination images with a low-computational complexity.
入藏号: WOS:000451759800002
ISSN: 1751-9659
eISSN: 1751-9667
________________________________________
第 19 条,共 322 条
标题: The frequency behavior of hysteresis loops in Mn:Fe:KTN ferroelectric single crystal
作者: Ma, XG (Ma, Xiangguo); Li, Z (Li, Zhen); Lu, QN (Lu, Qieni); Li, BH (Li, Bihua); Zhang, MD (Zhang, Mingdi)
来源出版物: JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS 卷: 29 期: 23 页: 20500-20505 DOI: 10.1007/s10854-018-0185-8 出版年: DEC 2018
摘要: In this paper, the frequency (f) behavior of hysteresis loops in a tetragonal Mn:Fe:KTN crystal is investigated. We have found that the shape of P-E hysteresis loops experiences systemic f-dependent changes from an asymmetric double hysteresis loop to a normal single loop, as the frequency changes from high to low (150-0.01Hz). The shape of P-E loop is strongly f-dependent only at low frequency (f<1Hz) and f-independent at the high one (f10Hz), and the maximum polarization stays unchanged with f varying at the same temperature and amplitude of electric field. The frequency-dependent properties of hysteresis loop stem from the forced vibration of two types of electric dipoles induced by the off-center displacement and the local composition gradient distribution, with different response time to applied electric field. The results are of great value for enhancing device performance and fabricating required devices with specific performance characteristics.
入藏号: WOS:000448831000097
ISSN: 0957-4522
eISSN: 1573-482X
________________________________________
第 20 条,共 322 条
标题: Watt-level passively Q-switched and mode-locked Nd:YAG laser with a reflective MoS2 saturable absorber
作者: Zeng, YJ (Zeng, Yingjie); Wang, YG (Wang, Yonggang); Ren, W (Ren, Wei); Wang, HY (Wang, HongYing); Fu, FX (Fu, Fuxing); Wang, X (Wang, Xi); Zheng, QQ (Zheng, Qiqi); Chen, ZD (Chen, Zhendong); Wei, LL (Wei, Lianglei); Yang, XG (Yang, Xiguang); Wang, J (Wang, Jiang)
来源出版物: OPTICS AND LASER TECHNOLOGY 卷: 108 页: 355-359 DOI: 10.1016/j.optlastec.2018.07.003 出版年: DEC 2018
摘要: A passively Q-switched mode-locked Nd: YAG laser with a reflective molybdenum disulfide (MoS2) saturable absorber (SA) was demonstrated. The MoS2 SA was made by spin-coating the MoS2 nanoplates onto a home-made silver mirror. The modulation depth of the MoS2 SA was measured to be 3.05%. We optimized the laser beam radii in the crystal and on the reflective silver mirror with MoS2 by accurately designing the oscillator cavity. Under an incident pump power of 11 W, we got the maximum average output power as high as 1.06 W with a repetition rate of 94.72 MHz. The experimental results validated the outstanding characteristics of MoS2 SA and its further amplification possibility in high power all-solid-state pulse lasers. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000443664100042
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zeng, Yingjie         V-2059-2017         

ISSN: 0030-3992
eISSN: 1879-2545
________________________________________
第 21 条,共 322 条
标题: Aberration correction for improving the image quality in STED microscopy using the genetic algorithm
作者: Wang, LW (Wang, Luwei); Yan, W (Yan, Wei); Li, RZ (Li, Runze); Weng, XY (Weng, Xiaoyu); Zhang, J (Zhang, Jia); Yang, ZG (Yang, Zhigang); Liu, LW (Liu, Liwei); Ye, T (Ye, Tong); Qu, JL (Qu, Junle)
来源出版物: NANOPHOTONICS 卷: 7 期: 12 页: 1971-1980 DOI: 10.1515/nanoph-2018-0133 出版年: DEC 2018
摘要: With a purely optical modulation of fluorescent behaviors, stimulated emission depletion (STED) microscopy allows for far-field imaging with a diffraction-unlimited resolution in theory. The performance of STED microscopy is affected by many factors, of which aberrations induced by the optical system and biological samples can distort the wave front of the depletion beam at the focal plane to greatly deteriorate the spatial resolution and the image contrast. Therefore, aberration correction is imperative for STED imaging, especially for imaging thick specimens. Here, we present a wave front compensation approach based on the genetic algorithm (GA) to restore the distorted laser wave front for improving the quality of STED images. After performing aberration correction on two types of zebrafish samples, the signal intensity and the imaging resolution of STED images were both improved, where the thicknesses were 24 pm and 100 pm in the zebrafish retina sample and the zebrafish embryo sample, respectively. The results showed that the GA-based wave front compensation approach has the capability of correction for both system-induced and sample-induced aberrations. The elimination of aberrations can prompt STED imaging in deep tissues; therefore, STED microscopy can be expected to play an increasingly important role in super-resolution imaging related to the scientific research in biological fields.
入藏号: WOS:000451084700009
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yan, Wei                  0000-0002-0745-9514

ISSN: 2192-8606
eISSN: 2192-8614
________________________________________
第 22 条,共 322 条
标题: Wideband wavelength-tunable ultrafast fiber laser based on black phosphorus saturable absorber
作者: Li, WL (Li, Wenlei); Chen, GW (Chen, Guangwei); Wang, GM (Wang, Guomei); Zeng, C (Zeng, Chao); Zhao, W (Zhao, Wei)
来源出版物: LASER PHYSICS LETTERS 卷: 15 期: 12 文献号: 125102 DOI: 10.1088/1612-202X/aae786 出版年: DEC 2018
摘要: We report a wideband wavelength-tunable ultrafast fiber laser mode-locked with a few-layer black phosphorus (BP) saturable absorber. The proposed laser not only delivers picosecond stable conventional solitons but also exhibits flexible wavelength tunability from 1529 to 1592nm. It is experimentally demonstrated that the broadband saturable absorption property of BP and birefringence filtering effects in the cavity contribute significantly to the aforementioned merits. In addition, the round-trip model is established to numerically demonstrate the spectral evolution, and numerical results are in good agreement with experimental observations. The proposed laser system is compact and wavelength-tunable, which provides an efficient solution for applications where a widely tunable ultrafast fiber laser is required.
入藏号: WOS:000448864700001
ISSN: 1612-2011
eISSN: 1612-202X
________________________________________
第 23 条,共 322 条
标题: SESAM mode-locked all-polarization-maintaining fiber linear cavity ytterbium laser source with spectral filter as pulse shaper
作者: Lv, ZG (Lv, Zhiguo); Yang, Z (Yang, Zhi); Li, F (Li, Feng); Yang, XJ (Yang, Xiaojun); Tang, SK (Tang, Shukui); Yang, Y (Yang, Yang); Li, QL (Li, Qianglong); Wang, YS (Wang, Yishan); Zhao, W (Zhao, Wei)
来源出版物: LASER PHYSICS 卷: 28 期: 12 文献号: 125103 DOI: 10.1088/1555-6611/aae18b 出版年: DEC 2018
摘要: We report on a SESAM mode-locked all-normal-dispersion all-polarization-maintaining (PM) ytterbium-doped picosecond fiber laser. The linear cavity oscillator utilizes a narrowband filter for pulse shaping for the first time, to the best of our knowledge. Stable mode-locked pulses with a repetition rate of 29 MHz are achieved under a maximum average output power of 35.9 mW. The linearly polarized pulses have a full width at half maximum of 4nm at a central wavelength of 1032nm, and a 20.6ps pulse duration with pulse energies of 1.2 nJ. Compared to the reported experiment scheme of the generation of the picosecond pulses, the presented all-PM-fiber linear cavity mode-locked oscillator with spectral filter as pulse modulation component provides a new method for the realization of the compact-sized low-cost high-performance picosecond pulses and has important potential applications in a seeding master-oscillator power amplification system.
入藏号: WOS:000446775100001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
qianglong, li         V-6278-2019         

ISSN: 1054-660X
eISSN: 1555-6611
________________________________________
第 24 条,共 322 条
标题: A highly efficient magnetically confined ion source for real time on-line monitoring of trace compounds in ambient air
作者: Tang, J (Tang, Jie); Ding, XL (Ding, Xuelu); Zhang, P (Zhang, Pei); Lei, BY (Lei, Bingying); Zhao, ZJ (Zhao, Zhongjun); Duan, YX (Duan, Yixiang)
来源出版物: CHEMICAL COMMUNICATIONS 卷: 54 期: 92 页: 12962-12965 DOI: 10.1039/c8cc05360j 出版年: NOV 28 2018
摘要: We fabricate a high-efficient ion source for real time on-line monitoring of trace compounds in ambient air by introducing a weak longitudinal magnetic field to a micro-fabricated DC glow discharge. Mass spectrometric detection of various samples indicates that the signal intensity increases by an order of magnitude and the limit of detection can be lowered to 1/10 of the original level. This improvement results from the increasing ion transport efficiency through the magnetic confinement.
入藏号: WOS:000450435700011
PubMed ID: 30382248
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Tang, Jie                  0000-0003-2126-6812

ISSN: 1359-7345
eISSN: 1364-548X
________________________________________
第 25 条,共 322 条
标题: Spectral clustering based on iterative optimization for large-scale and high-dimensional data
作者: Zhao, Y (Zhao, Yang); Yuan, Y (Yuan, Yuan); Nie, FP (Nie, Feiping); Wang, Q (Wang, Qi)
来源出版物: NEUROCOMPUTING 卷: 318 页: 227-235 DOI: 10.1016/j.neucom.2018.08.059 出版年: NOV 27 2018
摘要: Spectral graph theoretic methods have been a fundamental and important topic in the field of manifold learning and it has become a vital tool in data clustering. However, spectral clustering approaches are limited by their computational demands. It would be too expensive to provide an optimal approximation for spectral decomposition in dealing with large-scale and high-dimensional data sets. On the other hand, the rapid development of data on the Web has posed many rising challenges to the traditional single-task clustering, while the multi-task clustering provides many new thoughts for real-world applications such as video segmentation. In this paper, we will study a Spectral Clustering based on Iterative Optimization (SCIO), which solves the spectral decomposition problem of large-scale and high-dimensional data sets and it well performs on multi-task clustering. Extensive experiments on various synthetic data sets and real-world data sets demonstrate that the proposed method provides an efficient solution for spectral clustering. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000445763500021
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Nie, Feiping         B-3039-2012         
Nie, Feiping                  0000-0002-0871-6519
Wang, Qi                  0000-0002-7028-4956

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 26 条,共 322 条
标题: All-optical imaging and tracking technology for rectilinear motion targets through scattering media
作者: Jia, H (Jia Hui); Luo, XJ (Luo Xiu-Juan); Zhang, Y (Zhang Yu); Lan, FY (Lan Fu-Yang); Liu, H (Liu Hui); Chen, ML (Chen Ming-Lai)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 22 文献号: 224202 DOI: 10.7498/aps.67.20180955 出版年: NOV 20 2018
摘要: Light scattering is a main factor that restricts optical transmission and deteriorates optical imaging performance. All-optical imaging for moving targets through complex scattering media is one of the most challenging techniques. In this paper, a method for real-time tracking of moving targets through scattering medium is presented by utilizing optical memory-effect and autocorrelation of speckle difference. In the experiment on imaging through a scattering medium, an object is hidden at a distance u behind a highly scattering medium. The object is illuminated by a spatially incoherent pseudothermal light source. The light is diffused through the scattering medium. Camera placed at a distance u(0) on the other side of the medium records the pattern of the scattered light. According to the theory of optical memory-effect, the process of scattering imaging is a convolution process of point spread function (PSF) and object. In the procedure of object moving, the scattered signals from two frames are captured. The background noise could be removed by subtracting the two captured image. Then, the autocorrelation operation calculates the speckle difference, and hidden targets can be effectively reconstructed with the phase retrieval algorithm. The experiment demonstrates the imaging of targets with different speeds. The results have shown that the faster the speed, the worse the imaging quality is. High-speed moving objects can be imaged by using a high frame rate camera to reduce the exposure time or by disambiguating the speckle pattern. In subsequent experiments, the distance of the target movement is calculated with the magnification of the system. The collected two frames of speckle must be within the same memory effect angle. Only in this way can the calculation accuracy of the motion distance be guaranteed. With the moving of the target, the cross-correlation information of the target appears at different positions of the speckle difference autocorrelation map. Finally, according to the cross-correlation of the target at different locations, the real-time tracking of the moving target can be realized. Due to the Gaussian distribution of the laser beam, the cross-correlation intensity of the speckle difference autocorrelation map decreases with the object moving further. Therefore the target moving range is limited by the laser beam diameter, intensity distribution and camera field angle. It is verified experimentally that the imaging and tracking of moving targets which are hidden behind the ground glass can be achieved successfully by using this method. This kind of imaging and real-time tracking technology for targets moving through the scattering medium has important potential applications in biomedicine and other fields.
入藏号: WOS:000455402400012
ISSN: 1000-3290
________________________________________
第 27 条,共 322 条
标题: Sub-wavelength focusing based on all-dielectric polarization-independent metalens
作者: Zhao, W (Zhao, Wei); Li, XY (Li, Xingyi); Li, SQ (Li, Siqi); Ge, ZQ (Ge, Zhiqiang); Liu, ML (Liu, Mulong); Li, ZY (Li, Zhongyu); Du, SJ (Du, Shujian)
来源出版物: INTERNATIONAL JOURNAL OF MODERN PHYSICS B 卷: 32 期: 29 文献号: 1850321 DOI: 10.1142/S0217979218503216 出版年: NOV 20 2018
摘要: We have proposed an all-dielectric polarization-independent metalens, which can be used for sub-wavelength focusing. The phase discontinuity of transmission light is produced by varying the diameter of the nanopillar. In this way, the incident light can be focused into sub-wavelength spot. Besides, finite-difference time-domain results show that near diffraction limit focusing is realized for the wavelength from 580 nm to 750 nm, which means the proposed metalens possesses a broad operation bandwidth. This all-dielectric metalens features polarization independent and broad bandwidth, and thus promises great potential for the applications of nanolithography, dense storage and biophotonics.
入藏号: WOS:000451225000004
ISSN: 0217-9792
eISSN: 1793-6578
________________________________________
第 28 条,共 322 条
标题: Three-dimensions thermal model of a high-power diode laser bar
作者: Wu, DH (Wu, Di-Hai); Zah, CE (Zah, Chung-En); Liu, XS (Liu, Xingsheng)
来源出版物: APPLIED OPTICS 卷: 57 期: 33 页: 9868-9876 DOI: 10.1364/AO.57.009868 出版年: NOV 20 2018
摘要: An analytical, three-dimensional, steady-state thermal model of a high-power diode laser bar is presented in this paper. The heat spreading angle in a laser bar heat sink, subjected to several convective conditions on the bottom-side, was calculated with this model. Thermal design curves for the heat sink and submount are also presented. Special discussion is presented for two kinds of our conduction-cooled laser bars. Finite element simulation and experimental results based on the wavelength shift method are compared with this analytical solution. The familiar 45 degrees angle in thermal design for a commercial hard solder conduction-cooled laser bar was found to lead to a 12% increase in thermal resistance relative to a free lateral diffusion heat sink. (C) 2018 Optical Society of America
入藏号: WOS:000450620700021
PubMed ID: 30462024
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
ZAH, CHUNG-EN         R-3016-2019         

ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 29 条,共 322 条
标题: Customizing supercontinuum generation via on-chip adaptive temporal pulse-splitting
作者: Wetzel, B (Wetzel, Benjamin); Kues, M (Kues, Michael); Roztocki, P (Roztocki, Piotr); Reimer, C (Reimer, Christian); Godin, PL (Godin, Pierre-Luc); Rowley, M (Rowley, Maxwell); Little, BE (Little, Brent E.); Chu, ST (Chu, Sai T.); Viktorov, EA (Viktorov, Evgeny A.); Moss, DJ (Moss, David J.); Pasquazi, A (Pasquazi, Alessia); Peccianti, M (Peccianti, Marco); Morandotti, R (Morandotti, Roberto)
来源出版物: NATURE COMMUNICATIONS 卷: 9 文献号: 4884 DOI: 10.1038/s41467-018-07141-w 出版年: NOV 20 2018
摘要: Modern optical systems increasingly rely on complex physical processes that require accessible control to meet target performance characteristics. In particular, advanced light sources, sought for, for example, imaging and metrology, are based on nonlinear optical dynamics whose output properties must often finely match application requirements. However, in these systems, the availability of control parameters (e.g., the optical field shape, as well as propagation medium properties) and the means to adjust them in a versatile manner are usually limited. Moreover, numerically finding the optimal parameter set for such complex dynamics is typically computationally intractable. Here, we use an actively controlled photonic chip to prepare and manipulate patterns of femtosecond optical pulses that give access to an enhanced parameter space in the framework of supercontinuum generation. Taking advantage of machine learning concepts, we exploit this tunable access and experimentally demonstrate the customization of nonlinear interactions for tailoring supercontinuum properties.
入藏号: WOS:000450580600001
PubMed ID: 30459363
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Viktorov, Evgeny         AAH-3699-2019         
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Peccianti, Marco         F-7127-2011         0000-0001-8894-496X
Wetzel, Benjamin         P-3187-2019         0000-0002-2691-0307
Pasquazi, Alessia         J-8521-2014         0000-0003-3330-584X
Rowley, Maxwell                  0000-0002-2279-2710

ISSN: 2041-1723
________________________________________
第 30 条,共 322 条
标题: Action recognition using spatial-optical data organization and sequential learning framework
作者: Yuan, Y (Yuan, Yuan); Zhao, Y (Zhao, Yang); Wang, Q (Wang, Qi)
来源出版物: NEUROCOMPUTING 卷: 315 页: 221-233 DOI: 10.1016/j.neucom.2018.06.071 出版年: NOV 13 2018
摘要: Recognizing human actions in videos is a challenging problem owning to complex motion appearance, various backgrounds and semantic gap between low-level features and high-level semantics. Existing methods have scored some achievements and many new thoughts have been proposed for action recognition. They focus on designing a robust feature description and training an elaborate learning model, and many of them can benefit from a two-stream network with a stack of RGB frames and optical flow frames. However, these features for human action representation are struggling with the limited feature representation as RGB videos are confused by static appearance redundancy and optical flow videos cannot represent the detailed appearance. To solve these problems, we propose an efficient algorithm based on the spatial-optical data organization and the sequential learning framework. There are two contributions of our method: a novel data organization based on hierarchical weighting segmentation and optical flow for video representation, and a lightweight deep learning model based on the Convolutional 3D (C3D) network and the Recurrent Neural Network (RNN) for complicated action recognition. The new data organization aggregates the merits of motion appearance, movement trajectories and optical flow in a creative way to highlight the meaningful information. And the proposed lightweight model has an insight into patterns and semantics of sequential data by low-level spatiotemporal feature extraction and high-level information mining. The proposed method is evaluated on the state-of-the-art dataset and the results demonstrate that our method have a good performance for complex human action recognition. (c) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000445934400022
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wang, Qi                  0000-0002-7028-4956

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 31 条,共 322 条
标题: Patient-specific ECG classification by deeper CNN from generic to dedicated
作者: Li, YZ (Li, Yazhao); Pang, YW (Pang, Yanwei); Wang, J (Wang, Jian); Li, XL (Li, Xuelong)
来源出版物: NEUROCOMPUTING 卷: 314 页: 336-346 DOI: 10.1016/j.neucom.2018.06.068 出版年: NOV 7 2018
摘要: This paper presents a new mechanism which is more effective for wearable devices to classify patient-specific electrocardiogram (ECG) heartbeats. In our method, a Generic Convolutional Neural Network (GCNN) is trained first using a large number of heartbeats without distinguishing patients. Based on the GCNN, fine-tuning technique is applied to modify the GCNN to a Tuned Dedicated CNN (TDCNN) for the corresponding individual. Notably, only the GCNN instead of common training data is required to be stored into wearable devices. Moreover, only fine-tuning with several seconds rather than dozens of minutes is needed before the TDCNN is used to monitor the long-term ECG signals in clinical. To accelerate the ECG classification, only the original ECG heartbeat is input to the CNN without other extended information from the neighbor heartbeats or FFT representation. A deeper CNN architecture with small-scale convolutional kernels is adopted to improve the speed and accuracy for classification. With deeper CNN, hierarchical features can be extracted to help improve the accuracy of ECG classification. The state-of-the-art performance on efficiency and accuracy for ECG classification over MIT-BIH dataset is achieved by the proposed method. The effectiveness and superiority for detecting ventricular ectopic beats (VEB) and supraventricular ectopic beats (SVEB) events are demonstrated. The proposed mechanism of fine-tuning the GCNN to TDCNN improves the efficiency for training patient-specific CNN classifier. Because of the computational efficiency of fine-tuning, ECG diagnosis and heart monitoring can be easily implemented with popular wearable devices in practice. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000443718400033
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 32 条,共 322 条
标题: Ultrafast soliton and stretched-pulse switchable mode-locked fiber laser with hybrid structure of multimode fiber based saturable absorber
作者: Zhao, FY (Zhao, Fengyan); Wang, YS (Wang, Yishan); Wang, HS (Wang, Hushan); Yan, ZJ (Yan, Zhijun); Hu, XH (Hu, Xiaohong); Zhang, W (Zhang, Wei); Zhang, T (Zhang, Ting); Zhou, KM (Zhou, Kaiming)
来源出版物: SCIENTIFIC REPORTS 卷: 8 文献号: 16369 DOI: 10.1038/s41598-018-34762-4 出版年: NOV 6 2018
摘要: We demonstrate an all-fiber mode locked laser based on hybrid structure of multimode fiber saturable absorber (SA) that can realize both conventional soliton and stretched-pulse states. Stable 16.44 MHz conventional soliton pulses are achieved by injecting 80 mW threshold pump power. By increasing the incident pump power to 420 mW, the laser evolves from soliton operation into stretched-pulse mode locking state. 310 fs stretched-pulse are obtained with the same repetition rate as the soliton pulses. The center wavelength and its 3 dB spectrum bandwidth are 1603 nm and 14.2 nm, respectively. For the first time, we experimentally confirm transition between conventional soliton and stretched-pulse in 1.5 mu m mode-locked fiber laser by introducing multimode optical fiber SA. Moreover, the maximum single pulse energy of nearly 1 nJ is achieved. Such all-fiber mode-locked lasers based on hybrid structure of multimode fiber are attractive for practical applications without damage and the limitation of life time.
入藏号: WOS:000449274000002
PubMed ID: 30401821
ISSN: 2045-2322
________________________________________
第 33 条,共 322 条
标题: Attosecond relative delay measurement using transient-grating frequency-resolved optical grating
作者: Huang, P (Huang Pei); Fang, SB (Fang Shao-Bo); Huang, HD (Huang Hang-Dong); Zhao, K (Zhao Kun); Teng, H (Teng Hao); Hou, X (Hou Xun); Wei, ZY (Wei Zhi-Yi)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 21 文献号: 214202 DOI: 10.7498/aps.67.20181570 出版年: NOV 5 2018
摘要: The accurate and precise controlling of the attosecond time delay between the sub-pulses within a hundredth of an optical cycle is the key ingredient for the sophisticated custom-tailored coherent waveform synthesizer. The attosecond delay control technique commonly experiences the "complete" characterization of the ultrashort sub-cycle pulses, which includes the spatiotemporal pulse characterization of the synthesized waveform and the attosecond relative delay between the parent pulses. In this work, the relative time delay between spectrally separated ultrashort parent pulses is characterized in an interferometer scheme with a background-free transient-grating frequency-resolved optical grating (TG-FROG). The TG-FROG geometry accurately measures the full time-dependent intensity and phase of ultrashort laser pulses in a wide range of regime (from ultraviolet to infrared) and offers significant advantages over other nonlinear-optical processes geometries (i.e., the polarization-gate-FROG, the self-diffraction-FROG, the second-harmonic generation-FROG and the third-harmonic-generation-FROG). The attosecond measurement accuracy is achieved for the first time, to the best of our knowledge. In this experiment, the output of a carrier-envelope-phase-stable Ti:sapphire amplifier (sub-30-fs, over-l-mJ, 1 kHz) is spectrally broadened in a neon-filled hollow-core fiber with an inner diameter of 250 mu m. The transmission through the pressure-gradient hollow-core fiber results in an mJ-level octave-spanning white-light supercontinuum, supporting a sub-3-fs Fourier transform-limited pulse. The supercontinuum is spectrally divided into two parent pulses by using a dichroic mirror. The sub-pulses are individually compressed by the custom-designed double-chirped mirrors and wedge pairs. The short and long wavelength pulses are separately compressed in few-cycle regime, yielding pulses with 6.7 fs and 9.8 fs, respectively. This technique overcomes the bottlenecks in the traditional delay measurement and should be applicable for many ultra-broadband pulse characterizations with extremely simple and alignment-free delay control device used. Furthermore, this new method will be easily adapted for the ultra-broadband two-dimensional electronic spectroscopy, the advanced temporal cloaking, and the field of sub-cycle arbitrary coherent waveform synthesizer for controlling strong-field interactions in atoms, molecules, solids, and nanostructures. We foresee that in the near future this novel technology will be very attractive for various applications in the next-generation light sources such as the Synergetic Extreme Condition User Facility in Beijing, China.
入藏号: WOS:000449700800013
ISSN: 1000-3290
________________________________________
第 34 条,共 322 条
标题: Iterative Filtering and Structural Features for Hyperspectral Image Classification with Limited Samples
作者: Wang, WN (Wang, Wenning); Liu, XB (Liu, Xuebin); Mou, XQ (Mou, Xuanqin); Sun, L (Sun, Li)
来源出版物: CANADIAN JOURNAL OF REMOTE SENSING 卷: 44 期: 6 页: 575-587 DOI: 10.1080/07038992.2019.1572500 出版年: NOV 2 2018
摘要: Hyperspectral classification with limited training samples is challenging. The current work lies in two aspects: first, we change the statistical distribution of samples by iterative filtering based on the guide images. The filter is called a Simplified Bilateral Filter (SBF), which is a modified bilateral filter for clustering samples. Secondly, new structural convolution kernels are used to generate new hyperspectral data. Finally, the class label of the test sample after dimension reduction is determined by OMP classification or SVM classification. Experimental results on two hyperspectral datasets demonstrate the effectiveness of the proposed feature extraction method in improving classification accuracy with limited training samples.
入藏号: WOS:000463914400002
ISSN: 0703-8992
eISSN: 1712-7971
________________________________________
第 35 条,共 322 条
标题: Discriminative and Orthogonal Subspace Constraints-Based Nonnegative Matrix Factorization
作者: Li, XL (Li, Xuelong); Cui, GS (Cui, Guosheng); Dong, YS (Dong, Yongsheng)
来源出版物: ACM TRANSACTIONS ON INTELLIGENT SYSTEMS AND TECHNOLOGY 卷: 9 期: 6 文献号: 65 DOI: 10.1145/3229051 出版年: NOV 2018
摘要: Nonnegative matrix factorization (NMF) is one widely used feature extraction technology in the tasks of image clustering and image classification. For the former task, various unsupervised NMF methods based on the data distribution structure information have been proposed. While for the latter task, the label information of the dataset is one very important guiding. However, most previous proposed supervised NMF methods emphasis on imposing the discriminant constraints on the coefficient matrix. When dealing with new coming samples, the transpose or the pseudoinverse of the basis matrix is used to project these samples to the low dimension space. In this way, the label influence to the basis matrix is indirect. Although, there are also some methods trying to constrain the basis matrix in NMF framework, either they only restrict within-class samples or impose improper constraint on the basis matrix. To address these problems, in this article a novel NMF framework named discriminative and orthogonal subspace constraints-based nonnegative matrix factorization (DOSNMF) is proposed. In DOSNMF, the discriminative constraints are imposed on the projected subspace instead of the directly learned representation. In this manner, the discriminative information is directly connected with the projected subspace. At the same time, an orthogonal term is incorporated in DOSNMF to adjust the orthogonality of the learned basis matrix, which can ensure the orthogonality of the learned subspace and improve the sparseness of the basis matrix at the same time. This framework can be implemented in two ways. The first way is based on the manifold learning theory. In this way, two graphs, i.e., the intrinsic graph and the penalty graph, are constructed to capture the intra-class structure and the inter-class distinctness. With this design, both the manifold structure information and the discriminative information of the dataset are utilized. For convenience, we name this method as the name of the framework, i.e., DOSNMF. The second way is based on the Fisher's criterion, we name it Fisher's criterion-based DOSNMF (FDOSNMF). The objective functions of DOSNMF and FDOSNMF can be easily optimized using multiplicative update (MU) rules. The new methods are tested on five datasets and compared with several supervised and unsupervised variants of NMF. The experimental results reveal the effectiveness of the proposed methods.
入藏号: WOS:000455480700005
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         

ISSN: 2157-6904
eISSN: 2157-6912
________________________________________
第 36 条,共 322 条
标题: Multiwavelength Er-doped fiber laser using an all-fiber Lyot filter
作者: Zhao, ZH (Zhao, Zihao); Li, XL (Li, Xiaolei); Li, Y (Li, Yue); Qin, HB (Qin, Huabao); Wang, HS (Wang, Hushan); Luo, YY (Luo, Yiyang); Yan, ZJ (Yan, Zhijun); Sun, QZ (Sun, Qizhen); Liu, DM (Liu, Deming); Zhang, L (Zhang, Lin)
来源出版物: APPLIED OPTICS 卷: 57 期: 31 页: 9270-9274 DOI: 10.1364/AO.57.009270 出版年: NOV 1 2018
摘要: We experimentally demonstrated a multiwavelength Er-doped fiber ring laser system by employing an all-fiber Lyot filter (AFLF) and a highly nonlinear fiber (HNLF). The AFLF was employed as a polarizing filter to generate a nonlinear polarization rotation effect and the highly dense and narrow bandwidth comb-like channels. A 1-km-long HNLF was used to enhance the nonlinearity of the laser cavity and suppress the mode competition for multiwavelength operation. In the experiment, 97 laser output channels within a 3 dB bandwidth simultaneously were excited under 224 mW pump power. The power fluctuation of lasing channels was less than 0.182 dB, and the wavelength shift was less than 0.04 nm in 100 min, after treating the AFLF in a thermostatic ice bath. Meanwhile, the output laser was highly polarized with a degree of polarization up to 99.9%. (C) 2018 Optical Society of America
入藏号: WOS:000448953800010
PubMed ID: 30461967
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Luo, Yiyang         E-3067-2019         

ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 37 条,共 322 条
标题: Lightweight Design of Multi-Objective Topology for a Large-Aperture Space Mirror
作者: Qu, YJ (Qu, Yanjun); Jiang, YR (Jiang, Yanru); Feng, LJ (Feng, Liangjie); Li, XP (Li, Xupeng); Liu, B (Liu, Bei); Wang, W (Wang, Wei)
来源出版物: APPLIED SCIENCES-BASEL 卷: 8 期: 11 文献号: 2259 DOI: 10.3390/app8112259 出版年: NOV 2018
摘要: For a large-aperture space telescope, one of the key techniques is the method for designing the lightweight primary mirror assembly (PMA). In order to minimize the mirror surface error under axial gravity, lateral gravity, and polishing pressure at the same time, a method for topology optimization with multi-objective function combined with parametric optimization is introduced in this paper. The weighted compliance minimum is selected as the objective function to maximum the mirror structural stiffness. Then sensitivity analysis method and size optimization are used to determine the mirror structure parameters. Compared with two types of commonly used lightweight configurations, the new configuration design shows obvious superiority. In addition, the surface figure root mean square (RMS) of the mirror mounted by given bipod flexure (BF) under 1 g lateral gravity is minimized only with a value of 3.58 nm, which proves the effectiveness of the design method proposed in this paper.
入藏号: WOS:000451302800249
ISSN: 2076-3417
________________________________________
第 38 条,共 322 条
标题: Carboxyl graphene oxide solution saturable absorber for femtosecond mode-locked erbium-doped fiber laser
作者: Lv, RD (Lv, Rui-dong); Li, L (Li, Lu); Wang, YG (Wang, Yong-gang); Chen, ZD (Chen, Zhen-dong); Liu, SC (Liu, Si-cong); wang, X (wang, Xi); wang, J (wang, Jiang); Li, YF (Li, Yong-fang)
来源出版物: CHINESE PHYSICS B 卷: 27 期: 11 文献号: 114214 DOI: 10.1088/1674-1056/27/11/114214 出版年: NOV 2018
摘要: The carboxyl-functionalized graphene oxide (GO-COOH) is a kind of unique two-dimensional (2D) material and possesses excellent nonlinear saturable absorption property and high water-solubility. In this paper, we prepare saturable absorber (SA) device by depositing GO-COOH nanosheets aqueous solution on a D-shaped fiber. The modulation depth (MD) and saturable intensity of the SA are measured to be 9.6% and 19 MW/cm(2), respectively. By inserting the SA into the erbium-doped fiber (EDF) laser, a passively mode-locked EDF laser has been achieved with the spectrum center wavelength of 1562.76 nm. The pulse duration, repetition rate, and the signal-to-noise ratio (SNR) are 500 fs, 14.79 MHz, and 80 dB, respectively. The maximum average output power is measured to be 3.85 mW. These results indicate that the GO-COOH nanosheets SA can be used as a promising mode locker for the generation of ultrashort pulses.
入藏号: WOS:000450989100014
ISSN: 1674-1056
eISSN: 1741-4199
________________________________________
第 39 条,共 322 条
标题: Exploring Web Images to Enhance Skin Disease Analysis Under A Computer Vision Framework
作者: Xia, YJ (Xia, Yingjie); Zhang, LM (Zhang, Luming); Meng, L (Meng, Lei); Yan, Y (Yan, Yan); Nie, LQ (Nie, Liqiang); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON CYBERNETICS 卷: 48 期: 11 页: 3080-3091 DOI: 10.1109/TCYB.2017.2765665 出版年: NOV 2018
摘要: To benefit the skin care, this paper aims to design an automatic and effective visual analysis framework, with the expectation of recognizing the skin disease from a given image conveying the disease affected surface. This task is nontrivial, since it is hard to collect sufficient well-labeled samples. To address such problem, we present a novel transfer learning model, which is able to incorporate external knowledge obtained from the rich and relevant Web images contributed by grassroots. In particular, we first construct a target domain by crawling a small set of images from vertical and professional dermatological websites. We then construct a source domain by collecting a large set of skin disease related images from commercial search engines. To reinforce the learning performance in the target domain, we initially build a learning model in the target domain, and then seamlessly leverage the training samples in the source domain to enhance this learning model. The distribution gap between these two domains are bridged by a linear combination of Gaussian kernels. Instead of training models with low-level features, we resort to deep models to learn the succinct, invariant, and high-level image representations. Different from previous efforts that focus on a few types of skin diseases with a small and confidential set of images generated from hospitals, this paper targets at thousands of commonly seen skin diseases with publicly accessible Web images. Hence the proposed model is easily repeatable by other researchers and extendable to other disease types. Extensive experiments on a real-world dataset have demonstrated the superiority of our proposed method over the state-of-the-art competitors.
入藏号: WOS:000447825400005
PubMed ID: 29990098
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2168-2267
eISSN: 2168-2275
________________________________________
第 40 条,共 322 条
标题: CNNs-Based RGB-D Saliency Detection via Cross-View Transfer and Multiview Fusion
作者: Han, JW (Han, Junwei); Chen, H (Chen, Hao); Liu, N (Liu, Nian); Yan, CG (Yan, Chenggang); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON CYBERNETICS 卷: 48 期: 11 页: 3171-3183 DOI: 10.1109/TCYB.2017.2761775 出版年: NOV 2018
摘要: Salient object detection from RGB-D images aims to utilize both the depth view and RGB view to automatically localize objects of human interest in the scene. Although a few earlier efforts have been devoted to the study of this paper in recent years, two major challenges still remain: 1) how to leverage the depth view effectively to model the depth-induced saliency and 2) how to implement an optimal combination of the RGB view and depth view, which can make full use of complementary information among them. To address these two challenges, this paper proposes a novel framework based on convolutional neural networks (CNNs), which transfers the structure of the RGB-based deep neural network to be applicable for depth view and fuses the deep representations of both views automatically to obtain the final saliency map. In the proposed framework, the first challenge is modeled as a cross-view transfer problem and addressed by using the task-relevant initialization and adding deep supervision in hidden layer. The second challenge is addressed by a multiview CNN fusion model through a combination layer connecting the representation layers of RGB view and depth view. Comprehensive experiments on four benchmark datasets demonstrate the significant and consistent improvements of the proposed approach over other state-of-the-art methods.
入藏号: WOS:000447825400013
PubMed ID: 29990092
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2168-2267
eISSN: 2168-2275
________________________________________
第 41 条,共 322 条
标题: Structurally Incoherent Low-Rank Nonnegative Matrix Factorization for Image Classification
作者: Lu, YW (Lu, Yuwu); Yuan, C (Yuan, Chun); Zhu, WW (Zhu, Wenwu); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON IMAGE PROCESSING 卷: 27 期: 11 页: 5248-5260 DOI: 10.1109/TIP.2018.2855433 出版年: NOV 2018
摘要: As a popular dimensionality reduction method, nonnegative matrix factorization (NMF) has been widely used in image classification. However, the NMF does not consider discriminant information from the data themselves. In addition, most NMF-based methods use the Euclidean distance as a metric, which is sensitive to noise or outliers in data. To solve these problems, in this paper, we introduce structural incoherence and low-rank to NMF and propose a novel nonnegative factorization method, called structurally incoherent low-rank NMF (SILR-NMF), in which we jointly consider structural incoherence and low-rank properties of data for image classification. For the corrupted data, we use the L-1 norm as a constraint to ensure the noise is sparse. SILR-NMF learns a clean data matrix from the noisy data by low-rank learning. As a result, the SILR-NMF can capture the global structure information of the data, which is more robust than local information to noise. By introducing the structural incoherence of the learned clean data, SILR-NMF ensures the clean data points from different classes are as independent as possible. To verify the performance of the proposed method, extensive experiments are conducted on six image databases. The experimental results demonstrate that our proposed method has substantial gain over existing NMF approaches.
入藏号: WOS:000440203500004
PubMed ID: 30010572
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1057-7149
eISSN: 1941-0042
________________________________________
第 42 条,共 322 条
标题: Approximate Low-Rank Projection Learning for Feature Extraction
作者: Fang, XZ (Fang, Xiaozhao); Han, N (Han, Na); Wu, JG (Wu, Jigang); Xu, Y (Xu, Yong); Yang, J (Yang, Jian); Wong, WK (Wong, Wai Keung); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 11 页: 5228-5241 DOI: 10.1109/TNNLS.2018.2796133 出版年: NOV 2018
摘要: Feature extraction plays a significant role in pattern recognition. Recently, many representation-based feature extraction methods have been proposed and achieved successes in many applications. As an excellent unsupervised feature extraction method, latent low-rank representation (LatLRR) has shown its power in extracting salient features. However, LatLRR has the following three disadvantages: 1) the dimension of features obtained using LatLRR cannot be reduced, which is not preferred in feature extraction; 2) two low-rank matrices are separately learned so that the overall optimality may not be guaranteed; and 3) LatLRR is an unsupervised method, which by far has not been extended to the supervised scenario. To this end, in this paper, we first propose to use two different matrices to approximate the low-rank projection in LatLRR so that the dimension of obtained features can be reduced, which is more flexible than original LatLRR. Then, we treat the two low-rank matrices in LatLRR as a whole in the process of learning. In this way, they can be boosted mutually so that the obtained projection can extract more discriminative features. Finally, we extend LatLRR to the supervised scenario by integrating feature extraction with the ridge regression. Thus, the process of feature extraction is closely related to the classification so that the extracted features are discriminative. Extensive experiments are conducted on different databases for unsupervised and supervised feature extraction, and very encouraging results are achieved in comparison with many state-of-the-arts methods.
入藏号: WOS:000447832200005
PubMed ID: 29994377
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Lai, Zhihui         R-1000-2019         0000-0002-4388-3080
Li, Xuelong         Z-3785-2019         
Han, Na                  0000-0002-9639-7633
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 43 条,共 322 条
标题: Continuously tunable orthogonally polarized RF optical single sideband generator based on micro-ring resonators
作者: Xu, XY (Xu, Xingyuan); Wu, JY (Wu, Jiayang); Jia, LN (Jia, Linnan); Tan, MX (Tan, Mengxi); Nguyen, TG (Nguyen, Thach G.); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)
来源出版物: JOURNAL OF OPTICS 卷: 20 期: 11 文献号: 115701 DOI: 10.1088/2040-8986/aae3fe 出版年: NOV 2018
摘要: We demonstrate a continuously RF tunable orthogonally polarized optical single sideband (OP-OSSB) generator based on dual cascaded micro-ring resonators (MRRs). By splitting the input double sideband signal into an orthogonally polarized carrier and lower sideband via TE- and TM-polarized MRRs, an OP-OSSB signal is generated. A large tuning range of the optical carrier to sideband ratio of up to 57.3 dB is achieved by adjusting the polarization angle of the input light. The operation RF frequency of the OP-OSSB generator can be continuously tuned with a 21.4 GHz range via independent thermal control of the two MRRs. Our device represents a competitive approach towards OP-OSSB generation with wideband tunable RF operation, and is promising for photonic RF signal transmission and processing in radar and communication systems.
入藏号: WOS:000448104700001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X
Mitchell, Arnan         C-5017-2008         0000-0002-2463-2956
Nguyen, Thach                  0000-0002-8409-5638

ISSN: 2040-8978
eISSN: 2040-8986
________________________________________
第 44 条,共 322 条
标题: General condition of unidirectional mode conversion in periodic waveguide
作者: Zhang, LX (Zhang, Lingxuan); Wang, GX (Wang, Guoxi); Li, SQ (Li, Siqi); Ge, ZQ (Ge, Zhiqiang); Wang, WQ (Wang, Weiqiang); Sun, QB (Sun, Qibing); Wang, LR (Wang, Leiran); Gong, YK (Gong, Yongkang); Zhao, W (Zhao, Wei); Zhang, WF (Zhang, Wenfu)
来源出版物: JOURNAL OF OPTICS 卷: 20 期: 12 文献号: 125802 DOI: 10.1088/2040-8986/aaec24 出版年: NOV 2018
摘要: We present a general analytical theory for unidirectional mode conversion in a periodic waveguide at the sub-wavelength scale. According to this theory, two methods are proposed to achieve the unidirectional mode conversion. One method is to make the spectrum of the permittivity variation function asymmetrically, and the other is to employ the tensor permittivity and realize the non-reciprocal overlap of the coupled modes. Based on these two methods, five unidirectional mode converters are designed and demonstrated. The presented theory provides guidance for design of unidirectional devices in eliminating integrated backscattering, optical circulation and complex communication topology construction.
入藏号: WOS:000450650100001
ISSN: 2040-8978
eISSN: 2040-8986
________________________________________
第 45 条,共 322 条
标题: Compressed ultrafast photography by multi-encoding imaging
作者: Yang, CS (Yang, Chengshuai); Qi, DL (Qi, Dalong); Liang, JY (Liang, Jinyang); Wang, X (Wang, Xing); Cao, FY (Cao, Fengyan); He, YL (He, Yilin); Ouyang, XP (Ouyang, Xiaoping); Zhu, BQ (Zhu, Baoqiang); Wen, WL (Wen, Wenlong); Jia, TQ (Jia, Tianqing); Tian, JS (Tian, Jinshou); Gao, L (Gao, Liang); Sun, ZR (Sun, Zhenrong); Zhang, SA (Zhang, Shian); Wang, LHV (Wang, Lihong V.)
来源出版物: LASER PHYSICS LETTERS 卷: 15 期: 11 文献号: 116202 DOI: 10.1088/1612-202X/aae198 出版年: NOV 2018
摘要: Imaging ultrafast dynamic scenes has been long pursued by scientists. As a two-dimensional dynamic imaging technique, compressed ultrafast photography (CUP) provides the fastest receive-only camera to capture transient events. This technique is based on three-dimensional image reconstruction by combining streak imaging with compressed sensing (CS). However, the image quality and the frame rate of CUP are limited by the CS-based image reconstruction algorithms and the inherent temporal and spatial resolutions of the streak camera. Here, we report a new method to improve the temporal and spatial resolutions of CUP. Our numerical simulation and experimental verification show that by using a multi-encoding imaging method, both the image quality and the frame rate of CUP can be significantly improved beyond the intrinsic technical parameters. Importantly, the temporal resolution by our scheme can break the limitation of the streak camera. Therefore, this new technology has potential benefits in many applications that require the ultrafast dynamic scene image with high temporal and spatial resolutions.
入藏号: WOS:000446318500001
ISSN: 1612-2011
eISSN: 1612-202X
________________________________________
第 46 条,共 322 条
标题: Experimental observation of bound solitons with a nonlinear multimode interference-based saturable absorber
作者: Zhao, FY (Zhao, Fengyan); Wang, HS (Wang, Hushan); Hu, XH (Hu, Xiaohong); Wang, YS (Wang, Yishan); Zhang, W (Zhang, Wei); Zhang, T (Zhang, Ting); Sun, CD (Sun, Chuandong); Yan, ZJ (Yan, Zhijun)
来源出版物: LASER PHYSICS LETTERS 卷: 15 期: 11 文献号: 115106 DOI: 10.1088/1612-202X/aae050 出版年: NOV 2018
摘要: Both in-phase and anti-phase two-soliton bound states are observed using the structure of step-index multimode fiber and graded-index fiber as a new saturable absorber (SA) based on nonlinear multimode interference. To our knowledge, this is the first time that results are being reported of stable bound states with a multimode fiber laser as an SA in a passively mode-locked fiber laser. The bound solitons are verified to be stable for several hours in the laser cavity when keeping the experimental environment unchanged.
入藏号: WOS:000446317100001
ISSN: 1612-2011
eISSN: 1612-202X
________________________________________
第 47 条,共 322 条
标题: Hyperspectral image classification based on joint spectrum of spatial space and spectral space
作者: Zhang, XR (Zhang, Xiaorong); Pan, ZB (Pan, Zhibin); Lu, XQ (Lu, Xiaoqiang); Hu, BL (Hu, Bingliang); Zheng, X (Zheng, Xi)
来源出版物: MULTIMEDIA TOOLS AND APPLICATIONS 卷: 77 期: 22 页: 29759-29777 DOI: 10.1007/s11042-017-5552-6 出版年: NOV 2018
摘要: This paper presents a novel feature extraction model that incorporates local histogram in spatial space and pixel spectrum in spectral space, with the goal of hyperspectral image classification. We named this joint spectrum as 3D spectrum. Moreover, as a preprocessing step, an iterative procedure, which exploits spectral information in such a way that it considers corrupted bands existing in the data cube, is applied to original hyperspectral image. Further, Affine transform is applied to the bands chosen by the aforementioned procedure. The final feature is extracted by affine transform and 3D spectrum model, and as an input of widely used classifier of Support Vector Machine. As a post-processing step, multiple iterative results are fused in the level of probability. Our experimental results indicate that the proposed methodology leads to state-of-the-art classification results when combined with probabilistic classifiers for several widely used hyperspectral data sets, even when very only limited training samples are available.
入藏号: WOS:000451780800033
ISSN: 1380-7501
eISSN: 1573-7721
________________________________________
第 48 条,共 322 条
标题: Multi-modal gated recurrent units for image description
作者: Li, XL (Li, Xuelong); Yuan, AH (Yuan, Aihong); Lu, XQ (Lu, Xiaoqiang)
来源出版物: MULTIMEDIA TOOLS AND APPLICATIONS 卷: 77 期: 22 页: 29847-29869 DOI: 10.1007/s11042-018-5856-1 出版年: NOV 2018
摘要: Using a natural language sentence to describe the content of an image is a challenging but very important task. It is challenging because a description must not only capture objects contained in the image and the relationships among them, but also be relevant and grammatically correct. In this paper a multi-modal embedding model based on gated recur-rent units (GRU) which can generate variable-length description for a given image. In the training step, we apply the convolutional neural network (CNN) to extract the image feature. Then the feature is imported into the multi-modal GRU as well as the corresponding sentence representations. The multi-modal GRU learns the inter-modal relations between image and sentence. And in the testing step, when an image is imported to our multi-modal GRU model, a sentence which describes the image content is generated. The experimental results demonstrate that our multi-modal GRU model obtains the state-of-the-art performance on Flickr8K, Flickr30K and MS COCO datasets.
入藏号: WOS:000451780800038
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1380-7501
eISSN: 1573-7721
________________________________________
第 49 条,共 322 条
标题: Few-shot decision tree for diagnosis of ultrasound breast tumor using BI-RADS features
作者: Huang, QH (Huang, Qinghua); Zhang, F (Zhang, Fan); Li, XL (Li, Xuelong)
来源出版物: MULTIMEDIA TOOLS AND APPLICATIONS 卷: 77 期: 22 页: 29905-29918 DOI: 10.1007/s11042-018-6026-1 出版年: NOV 2018
摘要: This paper proposes an ultrasound breast tumor CAD system based on BI-RADS features scoring and decision tree algorithm. Because of the difficulty of biopsy label collection, the proposed system adopts a few-shot learning method. The SVM classifier is employed to preliminarily mark the unlabeled cases firstly. Then these unlabeled cases with the pseudo labels are combined with the few real-labeled cases to train the decision tree. To test the performance of the proposed method, 1208 ultrasound breast images were collected, and three well-experienced clinicians and three interns evaluated these images according to the BI-RADS scoring scheme. All of the images are transformed into vectors such that the algorithm can process. The experimental results show that the system performance improves significantly with the help of pseudo-labeled data. Compared to the decision tree trained by the real-labeled cases only, when the number of real-labeled cases was 40, the accuracy, specificity, sensitivity of the proposed system were increased by 2.05%, 2.47% and 1.81%, respectively; the positive predictive value (PPV) and the negative predictive value (NVP) were increased by 1.29% and 3.05%, respectively. Meanwhile, the performance of the proposed method was the same as the method using sufficient samples. When the number of the labeled cases reached 100, the accuracy, specificity, sensitivity, PPV and NVP of the proposed method were 90.03%, 87.02%, 91.68%, 93.07%, and 85.03%, respectively. The results demonstrate that our method can efficiently distinguish the breast tumor although the labeled data is not sufficient.
入藏号: WOS:000451780800041
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1380-7501
eISSN: 1573-7721
________________________________________
第 50 条,共 322 条
标题: Auto-weighted 2-dimensional maximum margin criterion
作者: Zhang, H (Zhang, Han); Nie, FP (Nie, Feiping); Zhang, R (Zhang, Rui); Li, XL (Li, Xuelong)
来源出版物: PATTERN RECOGNITION 卷: 83 页: 220-229 DOI: 10.1016/j.patcog.2018.05.021 出版年: NOV 2018
摘要: As a hot topic in machine learning, supervised learning is applied to both classification and recognition frequently. However, parameter-tuning in most supervised methods is a laborious work due to its complexity and unpredictability. In this paper, we propose an auto-weighted approach, termed as auto weighted 2-dimensional maximum margin criterion, which updates the introduced weight in each iteration automatically to leverage the associated terms, so that the weight becomes insensitive to initialization. In addition, the proposed method extracts features from 2-order data directly, i.e., image data. Moreover, we have an observation that the objective value in the proposed method could directly reflect the performance in classification task under the varying dimensionality, which is much beneficial to selection of the optimal dimensionality. Extensive experiments on several datasets are conducted to validate that our method is of great superiority compared to other approaches. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000442172200017
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Nie, Feiping         B-3039-2012         
Li, Xuelong         Z-3785-2019         
Zhang, Rui         U-4639-2017         0000-0001-9418-0863
Li, Xuelong                  0000-0002-0019-4197
Nie, Feiping                  0000-0002-0871-6519

ISSN: 0031-3203
eISSN: 1873-5142

第 51 条,共 322 条
标题: Discovery of trading points based on Bayesian modeling of trading rules
作者: Huang, QH (Huang, Qinghua); Kong, ZF (Kong, Zhoufan); Li, YS (Li, Yanshan); Yang, J (Yang, Jie); Li, XL (Li, Xuelong)
来源出版物: WORLD WIDE WEB-INTERNET AND WEB INFORMATION SYSTEMS 卷: 21 期: 6 页: 1473-1490 DOI: 10.1007/s11280-018-0534-9 出版年: NOV 2018
摘要: Mining hidden patterns with different technical indicators from the historical financial data has been regarded as an efficient way to determine the trading decisions in the financial market. Technical analysis has shown that a number of specific combinations of technical indicators could be treated as trading patterns for forecasting efficient trading directions. However, it is a challenging assignment to discover those combinations. In this paper, we innovatively propose to use a biclustering algorithm to detect the trading patterns. The discovered trading patterns are then utilized to forecast the market movement based on the Naive Bayesian algorithm. Finally, the Adaboost algorithm is applied to improve the accuracy of the forecasts. The proposed method was implemented on seven historical stock datasets and the average performance was compared with that of four existing algorithms. Experimental results demonstrated that the proposed algorithm outperforms the other four algorithms and can provide a valuable reference in the financial investments.
入藏号: WOS:000449485200003
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1386-145X
eISSN: 1573-1413
________________________________________
第 52 条,共 322 条
标题: A new breast tumor ultrasonography CAD system based on decision tree and BI-RADS features
作者: Huang, QH (Huang, Qinghua); Zhang, F (Zhang, Fan); Li, XL (Li, Xuelong)
来源出版物: WORLD WIDE WEB-INTERNET AND WEB INFORMATION SYSTEMS 卷: 21 期: 6 页: 1491-1504 DOI: 10.1007/s11280-017-0522-5 出版年: NOV 2018
摘要: In this paper, we present a novel computer-aided diagnostic (CAD) system based on the Breast Imaging Reporting and Data System (BI-RADS) terminology scores of screening ultrasonography (US). The decision tree algorithm is adopted to analyze the BI-RADS information to differentiate between the malignant and benign breast tumors. Although many ultrasonography CAD systems have been developed for decades, there are still some problems in clinical practice. Previous CAD systems are opaque for clinicians and cannot process the ultrasound image from different ultrasound machines. This study proposes a novel CAD system utilizing BI-RADS scoring standard and Classification and Regression Tree (CART) algorithm to overcome the two problems. The original dataset consists of 1300 ultrasound breast images. Three well-experienced clinicians evaluated all of the images according to the BI-RADS feature scoring standard. Subsequently, each image could be transformed into a 25x1 vector. The CART algorithm was finally used to classify these vectors. In the experiments, we used the oversampling method to balance the number of malignant samples and benign samples. The 5-fold cross validation was employed to evaluate the performance of the system. The accuracy reached 94.58%, the specificity was 98.84%, the sensitivity was 90.80%, the positive predictive value (PPV) was 98.91% and the negative predictive value (NVP) was 90.56%. The experiment results show that the proposed system can obtain a sufficient performance in the breast diagnosis and can effectively recognize the benign breast tumors in BI-RADS 3.
入藏号: WOS:000449485200004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1386-145X
eISSN: 1573-1413
________________________________________
第 53 条,共 322 条
标题: Optical and electrical analysis of multi-electrode cylindrical dielectric barrier discharge (DBD) plasma reactor
作者: Niu, GH (Niu, Guanghui); Li, YP (Li, Yanping); Tang, J (Tang, Jie); Wang, X (Wang, Xu); Duan, YX (Duan, Yixiang)
来源出版物: VACUUM 卷: 157 页: 465-474 DOI: 10.1016/j.vacuum.2018.09.025 出版年: NOV 2018
摘要: Aiming to decrease the dielectric barrier discharge (DBD) capacitive current, a new type of multi-electrode cylindrical DBD plasma reactor was proposed in this work. Due to the novel multi-electrode design, the discharge current peak value of the newly designed plasma reactor decreased by 66.24%, from 16.26 mA for the traditional device to 5.49 mA. Besides, the number of the micro-discharges was found almost 2 times higher than that of the traditional device, indicating the generating of more discharge channels (from 37 to 89). The enhanced corona discharge formed at the electrode edges caused by fringe effect was considered as the main reason. The optielectrical analysis was performed using multi-electrode plasma reactors with different electrode configurations. The changes of optical emission efficiency (I-eff), equivalent capacitance of dielectric layer (C-d) and the discharge gap (C-g) were investigated under different applied voltage, discharge length, interval between adjacent outer electrodes and electrode width. The experimental results indicated the efficient discharge length l and fringe effect were responsible for the variations of I-eff, C-d and C-g. Higher applied voltage resulted in a higher I-eff but higher current at the same time. Besides, C-d gradually increased along with the increased applied voltage while C-g presented the decreased trend. I-eff increased along with the enhanced fringe effect caused by the shorter electrode width and smaller interval between adjacent outer electrodes, while decreased with the increased discharge length. C-d and C-g decreased with increased interval between outer electrodes, but increased with the enhanced discharge length and electrode width. The voltage distribution analysis indicated that the change of I-eff was mainly due to the change of the voltage across the gas gap V-g. This work can give a deeper and further understanding on the discharge characteristics of the proposed multi-electrode plasma reactor.
入藏号: WOS:000449569600065
ISSN: 0042-207X
________________________________________
第 54 条,共 322 条
标题: Flexible double-cladding ytterbium fibre based 9 W mode-locked laser with 102 fs compressible pulse duration
作者: Lv, ZG (Lv, Zhiguo); Yang, Z (Yang, Zhi); Yang, XJ (Yang, Xiaojun); Li, F (Li, Feng); Li, QL (Li, Qianglong); Wan, YS (Wan, Yishan); Zhao, W (Zhao, Wei); Wei, YF (Wei, Yufeng)
来源出版物: LASER PHYSICS LETTERS 卷: 15 期: 11 文献号: 115109 DOI: 10.1088/1612-202X/aad945 出版年: NOV 2018
摘要: We report on a high power mode-locked femtosecond fiber laser oscillator with flexible double-cladding (DC) ytterbium-doped fiber (Yb-fiber) as gain medium and a fused fiber combiner as a pump coupling scheme, based on the nonlinear polarization evolution effect in a ring cavity configuration with a dual-stage birefringent plate as the spectral filter. Laser pulses with a pulse energy as high as 122 nJ and compressible pulse duration as short as 102 fs at 1041 mn center wavelength could been obtained. The experimentally recorded power fluctuations were better than 0.42% RMS and 0.40% RMS in 3 h under 5 W and 9 W output power, respectively. The measured beam quality factors M-2 were 1.3 in both the horizontal and perpendicular directions. To the best of our knowledge, this is the highest output power generated from a flexible DC Yb-fiber-based ultrashort pulse mode-locking fiber laser oscillator pumped with a fusion spliced combiner.
入藏号: WOS:000448146900001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
qianglong, li         V-6278-2019         

ISSN: 1612-2011
eISSN: 1612-202X
________________________________________
第 55 条,共 322 条
标题: Effect of uplink atmospheric wavefront distortion on image quality of sheared-beam imaging
作者: Lan, FY (Lan Fu-Yang); Luo, XJ (Luo Xiu-Juan); Fan, XW (Fan Xue-Wu); Zhang, Y (Zhang Yu); Chen, ML (Chen Ming-Lai); Liu, H (Liu Hui); Jia, H (Jia Hui)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 20 文献号: 204201 DOI: 10.7498/aps.67.20181144 出版年: OCT 20 2018
摘要: Sheared-beam imaging (SBI) is a non-traditional imaging technique in which utilized are three sheared coherent lasers for illumination, and detector array to receive the intensity of speckle pattern reflected from the target. Finally the image of target can be reconstructed by computer algorithm from the data collected before. The SBI has some advantages in high resolution imaging for long-distance space targets. However, the wavefront distortion caused by atmospheric turbulence is a key factor affecting the imaging quality of SBI. Therefore, this paper focuses on the influence of wavefront distortion caused by atmospheric turbulence on the extraction of target spectral information. Theoretical model of the influence of wavefront distortion on imaging is established. The effects of low-order and high-order atmosphere turbulence on SBI imaging quality are analysed respectively. It turns out that low-order atmosphere turbulence does not result in poor image quality nor low-resolution, and just change the position of target on the image plane. But the image quality can be degraded when the wavefront root mean square (RMS) value at the target plane, caused by high-order atmosphere turbulence, exceeds lambda/20. Beam emitted from larger aperture becomes more susceptible to perturbing effect, thus forming lower-quality wavefront. Considering that after passing through the atmosphere, beam also travels a long distance to reach the target surface. Targets at different heights will obtain different wavefront quality due to the diffraction of light. Thus the final wavefront quality is determined by turbulence intensity, aperture size and target height. Multi-layer phase-screen model and Hufnagel-Valley model are used to simulate the influences of near-earth (25 km) atmosphere on wavefront distortion at target plane with different imaging distances. Simulation results show that the wavefront RMS value rises with the increase of transmitting aperture diameter, and decreases with the increase of imaging distance. Transmitting aperture sizes in a range from 0.2 times To to twice To have been recommended for effective imaging by Hutchin [Hutchin R A 1993 Proc. SPIE 2029 161]. However, we find in our simulations that beams on the order of 2ro may cause significant wavefront error at short range target, and under some circumstances the clear image of target cannot be reconstructed. The imaging results of SBI at different laser transmitting apertures and different imaging distances are obtained, and evaluated by Strehl ratio. Imaging results show that choosing appropriate transmitting aperture size can effectively improve the imaging quality. But for the short-range targets, aperture size selection range presented by Hutchin can be too broad to be practicable. This paper suggests some approaches to choosing suitable aperture size for SBI system, and also providing a reference for the difference analysis of imaging quality for targets in different heights.
入藏号: WOS:000448520200008
ISSN: 1000-3290
________________________________________
第 56 条,共 322 条
标题: Development and testing of glass substrate Wolter-1 X-ray focusing mirror
作者: Li, LS (Li Lin-Sen); Qiang, PF (Qiang Peng-Fei); Sheng, LZ (Sheng Li-Zhi); Liu, Z (Liu Zhe); Zhou, XH (Zhou Xiao-Hong); Zhao, BS (Zhao Bao-Sheng); Zhang, CM (Zhang Chun-Min)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 20 文献号: 200701 DOI: 10.7498/aps.67.20181330 出版年: OCT 20 2018
摘要: The wolter-1 X-ray focusing mirror can reflect grazing incidence X-ray to the focal plane, which plays an important role in the astronomical detection and other fields due to its good image detecting capability. A geometric model of the optical system is established for theoretically deriving the optical path equations which is useful in this glass based focusing mirror designing, all the design parameters of the focusing mirror can be obtained by solving these equations. In the manufacturing process, the D263T glass is chosen to be the structural material of the focusing mirror due to its light weight and super smooth surface, after a slumping process, the flat glass mirror will have the shape of Wolter-1 X-ray focusing mirror. This slumping process has been used successfully in the manufacturing process of an American mission named The Nuclear Spectroscopic Telescope Array, which was launched in 2012. According to X-ray reflecting theory, the reflectivity of the Wolter-1 mirror can be improved significantly by coating metal film on the surface of the mirror. In this work, an iridium film is coated on the surface of the glass mirror through a vacuum evaporating process. In order to learn the influence of the focal spot caused by the mirror shape tolerance, the morphology of the mirror is tested by using a 3-D laser scan instrument. The results show that 50% of the total test points are located in the tolerance range of -10-10 mu m, in which the tolerance represents the difference between the actual lens profile and the ideal lens profile. Then the focal spot test is carried out with the help of a visible light test system: a laser collimator is installed in front of focusing mirror as an incidence light source, and a charge coupled device (CCD) is placed in the focal plane to gather the image of the focal spot, by calculating the gray level distribution of the focal spot image taken by the CCD, the energy distribution characteristic of focal spot can be obtained. The experimental results show that the focal length of the focusing mirror is 1.6 m, and the half-power surrounding diameter of the focal spot is 0.33 mm, corresponding to the angular resolution of 0.7 arc min.
入藏号: WOS:000448520200001
ISSN: 1000-3290
________________________________________
第 57 条,共 322 条
标题: Study of a high-precision pulsar angular position measuring method
作者: Li, Y (Li, Yao); Su, T (Su, Tong); Sheng, LZ (Sheng, Lizhi); Qiang, PF (Qiang, Pengfei); Zhao, BS (Zhao, Baosheng)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 29 文献号: 1850355 DOI: 10.1142/S0217984918503554 出版年: OCT 20 2018
摘要: Currently, very long baseline interferometry technology is widely used in the astronomical measurement areas, providing about 1 mu as pulsar positioning accuracy. However, these conventional methods cannot meet the higher position accuracy requirements of X-ray pulsar navigation. In this paper, we provide a novel method to measure the angular position based on X-ray intensity correlation. First, we show the relationship between the pulsar angular position and the X-ray intensity correlation. Second, we simulate the measurement error within the constraint on the photon energy fluctuations and compensation time. Finally, we propose a way to achieve such measurement. These theoretical analyses will improve the measurement accuracy of the pulsar angular position to a large extent.
入藏号: WOS:000448275000008
ISSN: 0217-9849
eISSN: 1793-6640
________________________________________
第 58 条,共 322 条
标题: Long-term measurement of high Q optical resonators based on optical vector network analysis with Pound Drever Hall technique
作者: Chen, ZH (Chen, Zenghui); Ye, L (Ye, Long); Dai, J (Dai, Jian); Zhang, T (Zhang, Tian); Yin, FF (Yin, Feifei); Zhou, Y (Zhou, Yue); Xu, K (Xu, Kun)
来源出版物: OPTICS EXPRESS 卷: 26 期: 21 页: 26888-26895 DOI: 10.1364/OE.26.026888 出版年: OCT 15 2018
摘要: An optical vector network analysis (OVNA) based on double sidebands (DSB) modulation and the Pound Drever Hall (PDH) technique is proposed and demonstrated. The frequency responses measurement of the high Q optical device with high stability are achieved by transmitting the DSB modulation signals through the device. The high stability can be realized by using the PDH feedback loop. Compared with the conventional DSB-based OVNA, the proposed scheme with only one step measurement avoids the complex post-processing. Moreover, the long-term measurement with high stability can also be realized. A proof-of-concept experiment is carried out, which achieves the magnitude and phase responses of the Fabry-Perot interferometer, and there is no frequency response shift even though the test time is up to 90 minutes. The proposed method is simple and stable, which can be potentially applied in characterization and fabrication of high Q optical devices. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000447287700008
PubMed ID: 30469766
ISSN: 1094-4087
________________________________________
第 59 条,共 322 条
标题: Frequency-demultiplication OEO for stable millimeter-wave signal generation utilizing phase-locked frequency-quadrupling
作者: Liu, JL (Liu, Jingliang); Liu, AN (Liu, Anni); Wu, ZH (Wu, Zhonghan); Gao, YR (Gao, Yiran); Dai, J (Dai, Jian); Liu, YN (Liu, Yuanan); Xu, K (Xu, Kun)
来源出版物: OPTICS EXPRESS 卷: 26 期: 21 页: 27358-27367 DOI: 10.1364/OE.26.027358 出版年: OCT 15 2018
摘要: A novel scheme for the generation and stabilization of the millimeter-wave (mmW) signal employing a frequency-demultiplication optoelectronic oscillator (FD-OEO) has been theoretically analyzed and experimentally demonstrated. The FD-OEO can keep sustaining without optical first-order sidebands, which would help to simplify the photonic-assisted frequency multiplication process and provide a wide frequency compensation range for the mmW system simultaneously. The stability of the generated 40-GHz mmW signal reaches 1.38 x 10(-12) at the average time of 100s. Besides, the measured single-sideband phase noise of the generated mmW signal exhibits as low as -103 dBc/Hz at 10-kHz offset frequency, maintaining a spurious level of -97 dBc. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000447287700110
PubMed ID: 30469806
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Liu, Jingliang                  0000-0001-8165-7079

ISSN: 1094-4087
________________________________________
第 60 条,共 322 条
标题: Orthogonally Polarized RF Optical Single Sideband Generation and Dual-Channel Equalization Based on an Integrated Microring Resonator
作者: Xu, XY (Xu, Xingyuan); Wu, JY (Wu, Jiayang); Tan, MX (Tan, Mengxi); Nguyen, TG (Nguyen, Thach G.); Chu, ST (Chu, Sai Tak); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)
来源出版物: JOURNAL OF LIGHTWAVE TECHNOLOGY 卷: 36 期: 20 页: 4808-4818 DOI: 10.1109/JLT.2018.2863704 出版年: OCT 15 2018
摘要: We demonstrate narrowband orthogonally polarized optical radio frequency (RF) single sideband generation as well as dual-channel equalization based on an integrated dual-polarization-mode high-Q microring resonator. The device operates in the optical communications band and enables narrowband RF operation at either 16.6 or 32.2 GHz, determined by the free spectral range and TE/TM mode interval in the resonator. We achieve a very large dynamic tuning range of over SS dB for both the optical carrier-to-sideband ratio and the dual-channel RF equalization.
入藏号: WOS:000444561700014
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Nguyen, Thach                  0000-0002-8409-5638
Mitchell, Arnan         C-5017-2008         0000-0002-2463-2956

ISSN: 0733-8724
eISSN: 1558-2213
________________________________________
第 61 条,共 322 条
标题: Study on he backscattering disturbance in duplex underwater wireless optical communication systems
作者: Han, B (Han, Biao); Zhao, W (Zhao, Wei); Meng, JC (Meng, Jiacheng); Zheng, YQ (Zheng, Yunqiang); Yang, Q (Yang, Qian)
来源出版物: APPLIED OPTICS 卷: 57 期: 29 页: 8478-8486 DOI: 10.1364/AO.57.008478 出版年: OCT 10 2018
摘要: Backscattering affects the performance of receivers in duplex underwater wireless optical communication (UWOC) systems. In this work, we study this issue using the Monte Carlo method. We show that with an increase of transmitter divergence angle, backscattering light power changes little while communication signal and optical signal-to-noise ratio (OSNR) are reduced dramatically at the receiver. With an increase of receiver field angle, backscattering light power becomes higher, communication signal is nearly unchanged, and OSNR is reduced greatly. With an increase of the separated distance between receiver and transmitter in each terminal, backscattering light power decreases quickly, communication signal is unchanged, and OSNR increases rapidly. With an increase of communication distance, backscattering light power is almost unchanged while both the communication signal and OSNR are reduced drastically. We demonstrate that, to reduce the impact of backscattering disturbance, the transmitter and receiver in each terminal should be placed at a greater distance and the latter should be with a smaller field angle. When the transmitting optical power or receiving sensitivity is too high, such disturbance is hard to suppress effectively. In this case, the system should work in half-duplex mode. These results will be useful for duplex UWOC system design. (C) 2018 Optical Society of America
入藏号: WOS:000446845800001
PubMed ID: 30461912
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 62 条,共 322 条
标题: Plasmonic topological edge states in ring-structure gate graphene
作者: Song, ZD (Song, Zidong); Liu, HJ (Liu, HongJun); Huang, N (Huang, Nan); Wang, ZL (Wang, ZhaoLu)
来源出版物: APPLIED OPTICS 卷: 57 期: 29 页: 8503-8507 DOI: 10.1364/AO.57.008503 出版年: OCT 10 2018
摘要: Topological photonic states exhibit unique robustness against defects, facilitating fault-tolerant photonic device applications. However, existing proposals either involve a sophisticated and bulky structure or can only operate in the microwave regime. We show a theoretical demonstration for highly confined topologically protected plasmonic states to be realized at infrared frequencies in monolayer graphene with a ring-structure gate. With a suitable bias voltage, the combined gate-graphene structure is shown to produce sufficiently strong Bragg scattering of graphene surface plasmons and to impart them with nontrivial topological properties. Our design is compact and could pave the way for dynamically reconfigurable, robust, nanoscale, integrated photonic devices. (C) 2018 Optical Society of America
入藏号: WOS:000446845800004
PubMed ID: 30461915
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 63 条,共 322 条
标题: All-dielectric metasurface for complete phase and amplitude control based on Pancharatnam-Berry phase and Fabry-Perot resonance
作者: Li, SQ (Li, Siqi); Wang, GX (Wang, Guoxi); Li, XY (Li, Xingyi); Liu, ML (Liu, Mulong); Ge, ZQ (Ge, Zhiqiang); Zhang, LX (Zhang, Lingxuan); Zeng, C (Zeng, Chao); Wang, LR (Wang, Leiran); Sun, QB (Sun, Qibing); Zhao, W (Zhao, Wei); Zhang, WF (Zhang, Wenfu)
来源出版物: APPLIED PHYSICS EXPRESS 卷: 11 期: 10 文献号: 105201 DOI: 10.7567/APEX.11.105201 出版年: OCT 2018
摘要: We propose an all-dielectric metasurface for simultaneously controlling phase and amplitude at the subwavelength scale. Based on the Pancharatnam-Berry phase and Fabry-Perot resonance, the variations of phase and amplitude can cover 0-2 pi and 0-1, respectively. Moreover, the polarization conversion efficiency and polarization conversion purity can reach up to 88 and 94%, respectively. By this method, a vortex beam generator with controllable topological charges and amplitudes is successfully designed. The proposed metasurface provides an effective method for the complete control of phase and amplitude, which can be used for holography, beam shaping, and the synthesis of complex wave fields. (C) 2018 The Japan Society of Applied Physics
入藏号: WOS:000443872500001
ISSN: 1882-0778
eISSN: 1882-0786
________________________________________
第 64 条,共 322 条
标题: Stability of Evolving Fuzzy Systems Based on Data Clouds
作者: Rong, HJ (Rong, Hai-Jun); Angelov, PP (Angelov, Plamen P.); Gu, XW (Gu, Xiaowei); Bai, JM (Bai, Jian-Ming)
来源出版物: IEEE TRANSACTIONS ON FUZZY SYSTEMS 卷: 26 期: 5 页: 2774-2784 DOI: 10.1109/TFUZZ.2018.2793258 出版年: OCT 2018
摘要: Evolving fuzzy systems (EFSs) are now well developed and widely used, thanks to their ability to self-adapt both their structures and parameters online. Since the concept was first introduced two decades ago, many different types of EFSs have been successfully implemented. However, there are only very few works considering the stability of the EFSs, and these studies were limited to certain types of membership functions with specifically predefined parameters, which largely increases the complexity of the learning process. At the same time, stability analysis is of paramount importance for control applications and provides the theoretical guarantees for the convergence of the learning algorithms. In this paper, we introduce the stability proof of a class of EFSs based on data clouds, which are grounded at the AnYa type fuzzy systems and the recently introduced empirical data analytics (EDA) methodological framework. By employing data clouds, the class of EFSs of AnYa type considered in this paper avoids the traditional way of defining membership functions for each input variable in an explicit manner and its learning process is entirely data driven. The stability of the considered EFS of AnYa type is proven through the Lyapunov theory, and the proof of stability shows that the average identification error converges to a small neighborhood of zero. Although, the stability proof presented in this paper is specially elaborated for the considered EFS, it is also applicable to general EFSs. The proposed method is illustrated with Box-Jenkins gas furnace problem, one nonlinear system identification problem, Mackey-Glass time series prediction problem, eight real-world benchmark regression problems as well as a high-frequency trading prediction problem. Compared with other EFSs, the numerical examples show that the considered EFS in this paper provides guaranteed stability as well as a better approximation accuracy.
入藏号: WOS:000446675400023
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Angelov, Plamen         AAE-8284-2019         0000-0002-5770-934X
Gu, Xiaowei                  0000-0001-9116-4761

ISSN: 1063-6706
eISSN: 1941-0034
________________________________________
第 65 条,共 322 条
标题: Optimal Clustering Framework for Hyperspectral Band Selection
作者: Wang, Q (Wang, Qi); Zhang, FH (Zhang, Fahong); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 卷: 56 期: 10 页: 5910-5922 DOI: 10.1109/TGRS.2018.2828161 出版年: OCT 2018
摘要: Band selection, by choosing a set of representative bands in a hyperspectral image, is an effective method to reduce the redundant information without compromising the original contents. Recently, various unsupervised band selection methods have been proposed, but most of them are based on approximation algorithms which can only obtain suboptimal solutions toward a specific objective function. This paper focuses on clustering-based band selection and proposes a new framework to solve the above dilemma, claiming the following contributions: 1) an optimal clustering framework, which can obtain the optimal clustering result for a particular form of objective function under a reasonable constraint; 2) a rank on clusters strategy, which provides an effective criterion to select bands on existing clustering structure; and 3) an automatic method to determine the number of the required bands, which can better evaluate the distinctive information produced by certain number of bands. In experiments, the proposed algorithm is compared with some state-of-the-art competitors. According to the experimental results, the proposed algorithm is robust and significantly outperforms the other methods on various data sets.
入藏号: WOS:000446300700027
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197
Wang, Qi                  0000-0002-7028-4956

ISSN: 0196-2892
eISSN: 1558-0644
________________________________________
第 66 条,共 322 条
标题: Local Regression and Global Information-Embedded Dimension Reduction
作者: Yao, C (Yao, Chao); Han, JW (Han, Junwei); Nie, FP (Nie, Feiping); Xiao, F (Xiao, Fu); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 10 页: 4882-4893 DOI: 10.1109/TNNLS.2017.2783384 出版年: OCT 2018
摘要: A large family of algorithms for unsupervised dimension reduction is based on both the local and global structures of the data. A fundamental step in these methods is to model the local geometrical structure of the data. However, the previous methods mainly ignore two facts in this step: 1) the dimensionality of the data is usually far larger than the number of local data, which is a typical ill-posed problem and 2) the data might be polluted by noise. These facts normally may lead to an inaccurate learned local structure and may degrade the final performance. In this paper, we propose a novel unsupervised dimension reduction method with the ability to address these problems effectively while also preserving the global information of the input data. Specifically, we first denoise the local data by preserving their principal components and we then apply a regularization term to the local modeling function to solve the illposed problem. Then, we use a linear regression model to capture the local geometrical structure, which is demonstrated to be insensitive to the parameters. Finally, we propose two criteria to simultaneously model both the local and the global information. Theoretical analyses for the relations between the proposed methods and some classical dimension-reduction methods are presented. The experimental results from various databases demonstrate the effectiveness of our methods.
入藏号: WOS:000445351300027
PubMed ID: 29993962
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Nie, Feiping         B-3039-2012         
Yao, C.         L-6166-2019         
Li, Xuelong                  0000-0002-0019-4197
Nie, Feiping                  0000-0002-0871-6519

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 67 条,共 322 条
标题: Matrix-Regularized Multiple Kernel Learning via (r, p) Norms
作者: Han, YN (Han, Yina); Yang, YX (Yang, Yixin); Li, XL (Li, Xuelong); Liu, QY (Liu, Qingyu); Ma, YL (Ma, Yuanliang)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 10 页: 4997-5007 DOI: 10.1109/TNNLS.2017.2785329 出版年: OCT 2018
摘要: This paper examines a matrix-regularized multiple kernel learning (MKL) technique based on a notion of (r, p) norms. For the problem of learning a linear combination in the support vector machine-based framework, model complexity is typically controlled using various regularization strategies on the combined kernel weights. Recent research has developed a generalized l(p)-norm MKL framework with tunable variable p(p >= 1) to support controlled intrinsic sparsity. Unfortunately, this "1-D" vector l(p)-norm hardly exploits potentially useful information on how the base kernels "interact." To allow for higher order kernel-pair relationships, we extend the "1-D" vector l(p)-MKL to the "2-D" matrix (r, p) norms (1 <= r, p < infinity). We develop a new formulation and an efficient optimization strategy for (r, p)-MKL with guaranteed convergence. A theoretical analysis and experiments on seven UCI data sets shed light on the superiority of (r, p)-MKL over l(p)-MKL in various scenarios.
入藏号: WOS:000445351300036
PubMed ID: 29994755
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 68 条,共 322 条
标题: Zero-Shot Learning Using Synthesised Unseen Visual Data with Diffusion Regularisation
作者: Long, Y (Long, Yang); Liu, L (Liu, Li); Shen, FM (Shen, Fumin); Shao, L (Shao, Ling); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 卷: 40 期: 10 页: 2498-2512 DOI: 10.1109/TPAMI.2017.2762295 出版年: OCT 2018
摘要: Sufficient training examples are the fundamental requirement for most of the learning tasks. However, collecting well-labelled training examples is costly. Inspired by Zero-shot Learning (ZSL) that can make use of visual attributes or natural language semantics as an intermediate level clue to associate low-level features with high-level classes, in a novel extension of this idea, we aim to synthesise training data for novel classes using only semantic attributes. Despite the simplicity of this idea, there are several challenges. First, how to prevent the synthesised data from over-fitting to training classes? Second, how to guarantee the synthesised data is discriminative for ZSL tasks? Third, we observe that only a few dimensions of the learnt features gain high variances whereas most of the remaining dimensions are not informative. Thus, the question is how to make the concentrated information diffuse to most of the dimensions of synthesised data. To address the above issues, we propose a novel embedding algorithm named Unseen Visual Data Synthesis (UVDS) that projects semantic features to the high-dimensional visual feature space. Two main techniques are introduced in our proposed algorithm. (1) We introduce a latent embedding space which aims to reconcile the structural difference between the visual and semantic spaces, meanwhile preserve the local structure. (2) We propose a novel Diffusion Regularisation (DR) that explicitly forces the variances to diffuse over most dimensions of the synthesised data. By an orthogonal rotation (more precisely, an orthogonal transformation), DR can remove the redundant correlated attributes and further alleviate the over-fitting problem. On four benchmark datasets, we demonstrate the benefit of using synthesised unseen data for zero-shot learning. Extensive experimental results suggest that our proposed approach significantly outperforms the state-of-the-art methods.
入藏号: WOS:000443875500016
PubMed ID: 29028188
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Shao, Ling         D-3535-2011         
Li, Xuelong         Z-3785-2019         
Long, Yang         X-4184-2019         0000-0002-2445-6112
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0162-8828
eISSN: 1939-3539
________________________________________
第 69 条,共 322 条
标题: Non-rigid point set registration by high-dimensional representation
作者: Huang, HM (Huang, Huimin); Zhou, ZF (Zhou, Zuofeng); Cao, JZ (Cao, Jianzhong)
来源出版物: IET IMAGE PROCESSING 卷: 12 期: 10 页: 1746-1752 DOI: 10.1049/iet-ipr.2017.1363 出版年: OCT 2018
摘要: Non-rigid point set registration is a key component in many computer vision and pattern recognition tasks. In this study, the authors propose a robust non-rigid point set registration method based on high-dimensional representation. Their central idea is to map the point sets into a high-dimensional space by integrating the relative structure information into the coordinates of points. On the one hand, the point set registration is formulated as the estimation of a mixture of densities in high-dimensional space. On the other hand, the relative distances are used to compute the local features which assign the membership probabilities of the mixture model. The proposed model captures discriminative relative information and enables to preserve both global and local structures of the point set during matching. Extensive experiments on both synthesised and real data demonstrate that the proposed method outperforms the state-of-the-art methods under various types of distortions, especially for the deformation and rotation degradations.
入藏号: WOS:000444686500007
ISSN: 1751-9659
eISSN: 1751-9667
________________________________________
第 70 条,共 322 条
标题: The preparation of Yttrium Aluminosilicate (YAS) Glass Fiber with heavy doping of Tm3+ from Polycrystalline YAG ceramics
作者: Zhang, YM (Zhang, Yeming); Qian, GQ (Qian, Guoquan); Xiao, XS (Xiao, Xusheng); Tian, XL (Tian, Xiangling); Ding, XQ (Ding, Xinqi); Ma, ZJ (Ma, Zhijun); Yang, LY (Yang, Luyun); Guo, HT (Guo, Haitao); Xu, SH (Xu, Shanhui); Yang, ZM (Yang, Zhongmin); Qiu, JR (Qiu, Jianrong)
来源出版物: JOURNAL OF THE AMERICAN CERAMIC SOCIETY 卷: 101 期: 10 页: 4627-4633 DOI: 10.1111/jace.15722 出版年: OCT 2018
摘要: Yttrium aluminosilicate (YAS) glass core fibers with different doping concentration of Tm3+ were fabricated by a Melt-in-Tube method from YAG polycrystalline ceramics. The effect of Tm3+ concentration on the spectroscopy of YAG ceramics and laser performance of YAS fibers were discussed. A homemade linear all-fiber laser based on the obtained 15% Tm3+-doped YAS fiber shows an optimized slope efficiency of 12.8%. The YAS fibers have been proven to be practical to achieve extremely high Tm3+ doping concentration and are a promising option for the 2.0m laser.
入藏号: WOS:000440554000029
ISSN: 0002-7820
eISSN: 1551-2916
________________________________________
第 71 条,共 322 条
标题: Adaptive Single Photon Compressed Imaging Based on Constructing a Smart Threshold Matrix
作者: Shangguan, W (Shangguan, Wentao); Yan, QR (Yan, Qiurong); Wang, H (Wang, Hui); Yuan, CL (Yuan, Chenglong); Li, B (Li, Bing); Wang, YH (Wang, Yuhao)
来源出版物: SENSORS 卷: 18 期: 10 文献号: 3449 DOI: 10.3390/s18103449 出版年: OCT 2018
摘要: We demonstrate a single-photon compressed imaging system based on single photon counting technology and compressed sensing theory. In order to cut down the measurement times and shorten the imaging time, a fast and efficient adaptive sampling method, suited for single-photon compressed imaging, is proposed. First, the pre-measured rough images are transformed into sparse bases as a priori information. Then a smart threshold matrix is designed by using large sparse coefficients of the rough image in sparse bases. The adaptive measurement matrix is obtained by modifying the original Gaussian random matrix with the specially designed threshold matrix. Building the adaptive measurement matrix requires only one level of sparse representation, which means that adaptive imaging can be achieved quickly with very little computation. The experimental results show that the reconstruction effect of the image measured using the adaptive measurement matrix is obviously superior than that of the Gaussian random matrix under different measurement times and different reconstruction algorithms.
入藏号: WOS:000448661500277
PubMed ID: 30322185
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wang, Yuhao         O-9322-2019         0000-0002-8445-0361
Shangguan, Wentao                  0000-0002-5784-5093
Yan, Qiurong                  0000-0003-4736-7435

ISSN: 1424-8220
________________________________________
第 72 条,共 322 条
标题: Effect of submount thickness on near-field bowing of laser diode arrays
作者: Zhang, HY (Zhang, Hongyou); Chen, TQ (Chen, Tianqi); Zhang, P (Zhang, Pu); Zah, CE (Zah, Chung-En); Liu, XS (Liu, Xingsheng)
来源出版物: APPLIED OPTICS 卷: 57 期: 28 页: 8407-8411 DOI: 10.1364/AO.57.008407 出版年: OCT 1 2018
摘要: Near-field bowing a laser diode bar (i.e., the "SMILE" effect) degrades the laser beam brightness, adversely affecting optical coupling and beam shaping. Due to thermally induced stress during the bonding process, the emitters in a laser diode array (LDA) are vertically displaced, which causes the SMILE effect. The mismatch between the coefficients of thermal expansion of an LDA (GaAs with 6.4 ppm/K) and a heat sink (Cu with 16.4 ppm/K) is a large obstacle in the LDA bonding process, because it provokes thermal stress and a large SMILE value, resulting in a larger divergence angle and a wider line after focusing and collimation. In this paper, the changes in stress and strain (SMILE value) and their effects on the laser bar as a function of the copper-tungsten (CuW) submount thickness were theoretically and experimentally studied. The finite element modeling simulations and experimental results show that the compression stress on the laser bar decreases with increasing CuW submount thickness because the CuW submount works as a buffer layer and can absorb stress. However, the laser bar out-of-plane strain (SMILE value) is approximately zero when the LDA is directly bonded onto the heat sink without a submount; the SMILE value is maximized when the CuW submount thickness is increased to approximately one half or 44% of the heat sink. Beyond that, the SMILE value decreases with increasing CuW submount thickness. (C) 2018 Optical Society of America
入藏号: WOS:000446048600039
PubMed ID: 30461795
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
ZAH, CHUNG-EN         R-3016-2019         
ZHANG, Hongyou                  0000-0001-5776-0025

ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 73 条,共 322 条
标题: Force prediction model considering material removal mechanism for axial ultrasonic vibration-assisted peripheral grinding of Zerodur
作者: Sun, GY (Sun, Guoyan); Zhao, LL (Zhao, Lingling); Ma, Z (Ma, Zhen); Zhao, QL (Zhao, Qingliang)
来源出版物: INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 卷: 98 期: 9-12 页: 2775-2789 DOI: 10.1007/s00170-018-2457-0 出版年: OCT 2018
摘要: Axial ultrasonic vibration-assisted peripheral grinding (AUPG) has the major advantages of simultaneously improving the grinding quality and material removal rate compared with conventional grinding methods. In this study, a grinding force prediction model for the AUPG of Zerodur was developed to investigate the generation mechanism of the grinding force for guidance in practical engineering applications. Taking into consideration the material removal mechanism, material properties and vibration impact, the three primary grinding force components were first separately modelled, namely, the ductile removal force in the ductile removal phase, the brittle removal force in the brittle removal phase and the frictional force of the friction process. The critical uncut chip thickness and maximum uncut chip thickness were subsequently researched to define the two material removal modes in the AUPG of Zerodur, namely, the ductile removal mode and the mixture of brittle and ductile removal mode. The grinding force models of these two material removal modes were developed using effective grinding force component models. The instantaneous variation of the grinding force with time and space was also analysed to derive models of the final time-averaged normal force, tangential force and axial force. Finally, grinding experiments were performed, the results of which showed that the prediction errors of the developed model were only 7.37 and 11.53% for the normal and tangential grinding forces, respectively. The axial ultrasonic vibration was also determined to reduce the surface roughness by 18.0% compared with conventional grinding, while the normal and tangential forces were reduced by 27.31 and 22.52%, respectively. This indicates that AUPG affords a significantly improved grinding surface quality. The developed model enables an understanding of the comprehensive mechanism of AUPG and provides a basis for the development of the grinding force models of the other brittle materials.
入藏号: WOS:000444704300045
ISSN: 0268-3768
eISSN: 1433-3015
________________________________________
第 74 条,共 322 条
标题: Influence of humidity on the characteristics of laser-induced air plasma
作者: Lei, BY (Lei, Bingying); Wang, J (Wang, Jing); Li, J (Li, Jing); Tang, J (Tang, Jie); Wang, YS (Wang, Yishan); Zhao, W (Zhao, Wei); Duan, YX (Duan, Yixiang)
来源出版物: JAPANESE JOURNAL OF APPLIED PHYSICS 卷: 57 期: 10 文献号: 106001 DOI: 10.7567/JJAP.57.106001 出版年: OCT 2018
摘要: The dependence of laser-induced breakdown spectroscopy (LIBS) on ambient conditions has not been clearly clarified as yet for element qualitative and quantitative analysis. To fill this gap, a laser-induced air plasma was produced by focusing a 1064-nm laser beam of Q-switched Nd:YAG pulse laser and the influence of relative humidity on the air plasma was systematically investigated by varying humidity at different laser irradiances. In contrast to the early findings, i.e., weak dependence of plasma properties on the humidity, some distinctive characteristics have been observed and explained. Examining the time-resolved emission spectra shows that the temporal evolution of spectral lines almost remains unchanged with the humidity and the influence of humidity on emission spectra can be neglected under a short gate width less than several hundred nanoseconds. As for the time-integrated emission spectra obtained at a higher laser irradiance, the increase in the emission intensity of H and O with the humidity is attributed to the increasing mole fraction of H and O and more laser energy that can be absorbed by the increasing water vapor. A faster growth of emission intensity of H and a slower increase of emission intensity of O respectively result from the relatively large increase of mole fraction of H and the relatively small increase of mole fraction of O with the humidity. Observations indicate that a shorter gate width or a lower laser irradiance is preferable in reducing the humidity influence and a certain magnitude of emission intensity of H and O spectral lines should be subtracted from the measured spectra for a more accurate and more reliable LIBS examination. (C) 2018 The Japan Society of Applied Physics
入藏号: WOS:000445119800001
ISSN: 0021-4922
eISSN: 1347-4065
________________________________________
第 75 条,共 322 条
标题: Broadband RF Channelizer Based on an Integrated Optical Frequency Kerr Comb Source
作者: Xu, XY (Xu, Xingyuan); Wu, JY (Wu, Jiayang); Nguyen, TG (Nguyen, Thach G.); Chu, ST (Chu, Sai Tak); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)
来源出版物: JOURNAL OF LIGHTWAVE TECHNOLOGY 卷: 36 期: 19 特刊: SI 页: 4519-4526 DOI: 10.1109/JLT.2018.2819172 出版年: OCT 1 2018
摘要: We report a broadband RF channelizer based on an integrated optical frequency Kerr micro-comb source, with an RF channelizing bandwidth of 90 GHz, a high RF spectral slice resolution of 1.04 GHz, and experimentally verify the RF performance up to 19 GHz. This approach of realizing RF channelizers offers reduced complexity, size, and potential cost for a wide range of applications to microwave signal detection.
入藏号: WOS:000443892500039
会议名称: International Topical Meeting on Microwave Photonics (MWP)
会议日期: OCT 23-26, 2017
会议地点: Tsinghua Univ, Beijing, PEOPLES R CHINA
会议赞助商: Beijing Univ Posts & Telecommunicat, CAS, Inst Semiconductors, NUAA, SWJTU, IPOC, LUSTER LightTech Grp, YOFC, IEEE Photon Soc, IEEE Microwave Theory & Tech Soc, TNList, Chinese Laser Press, EiC, Tektronix, Conquer, REALPHotoN, Miracle Photon, COMTEST
会议主办方: Tsinghua Univ
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X
Nguyen, Thach                  0000-0002-8409-5638
Mitchell, Arnan         C-5017-2008         0000-0002-2463-2956

ISSN: 0733-8724
eISSN: 1558-2213
________________________________________
第 76 条,共 322 条
标题: Investigation of stimulated Raman scattering in high-power co-pumping fiber amplifiers
作者: Zheng, JK (Zheng, Jinkun); Zhao, W (Zhao, Wei); Zhao, BY (Zhao, Baoyin); Li, Z (Li, Zhe); Li, G (Li, Gang); Gao, Q (Gao, Qi); Ju, P (Ju, Pei); Gao, W (Gao, Wei); She, SF (She, Shengfei); Wu, P (Wu, Peng)
来源出版物: LASER PHYSICS 卷: 28 期: 10 文献号: 105105 DOI: 10.1088/1555-6611/aad46b 出版年: OCT 2018
摘要: The stimulated Raman scattering (SRS) in a multi-kilowatt co-pumping fiber amplifier was investigated. Using 20 m of ytterbium-doped double-cladding fiber in the amplifier stage, an SRS product of 1032.9 nm could be clearly observed when the output laser power was more than 3360 W. By integrating the spectral curve, the ratios of laser power at 1080 nm and SRS to the total output power were 83.95% and 15.17% at the maximum power of 3699 W. In addition, the beam quality began to degenerate abruptly as the four-wave mixing and SRS components appeared. The M-2 factor was measured to be 3.06 at the maximal output power. The mode instability and nonlinear effects might be the main reason for beam quality degradation in high-power fiber amplifier systems.
入藏号: WOS:000441034300001
ISSN: 1054-660X
eISSN: 1555-6611
________________________________________
第 77 条,共 322 条
标题: Effect of the surface microstructure ablated by femtosecond laser on the bonding strength of EBCs for SiC/SiC composites
作者: Zhai, ZY (Zhai, Zhaoyang); Wang, WJ (Wang, Wenjun); Mei, XS (Mei, Xuesong); Li, M (Li, Ming); Cui, JL (Cui, Jianlei); Wang, FC (Wang, Fangcheng); Pan, AF (Pan, Aifei)
来源出版物: OPTICS COMMUNICATIONS 卷: 424 页: 137-144 DOI: 10.1016/j.optcom.2018.04.055 出版年: OCT 1 2018
摘要: The bonding strength between environmental barrier coatings (EBCs) and silicon carbide fiber reinforced silicon carbide (SiC/SiC) was improved by preparing microstructure on SiC/SiC surface with femtosecond laser. The processing morphologies with different parameters were compared. There was oxidation phenomenon at the edge of laser processing, and the degree of graphitization was increased. Without damage the internal fiber structure of SiC/SiC, reasonable processing parameters were selected, and microgroove structure was processed on the SiC/SiC surface using the femtosecond laser. The tension test results showed that, after the femtosecond laser machining, the bonding strength between EBCs and SiC/SiC could be improved by about 5.5%, and the time spent to reach the critical load was extended by 11.2%. The EBCs regularly adheres to the microgrooves formed by the femtosecond laser processing, while EBCs in the area without the laser processing was completely detached.
入藏号: WOS:000433425600023
ISSN: 0030-4018
eISSN: 1873-0310
________________________________________
第 78 条,共 322 条
标题: Image hashing with color vector angle
作者: Tang, ZJ (Tang, Zhenjun); Li, XL (Li, Xuelong); Zhang, XQ (Zhang, Xianquan); Zhang, SC (Zhang, Shichao); Dai, YM (Dai, Yumin)
来源出版物: NEUROCOMPUTING 卷: 308 页: 147-158 DOI: 10.1016/j.neucom.2018.04.057 出版年: SEP 25 2018
摘要: Color vector angle (CVA) is an important feature of processing color images and has been successfully developed and used in real applications, such as edge detection, indexing and retrieval of images. However, it is unsolved how to apply the CVA to efficiently generating an image hash. Also, most image hashing algorithms choose luminance component of color image for hash generation and cannot well capture the color information of images. To tackle these issues, we study efficient image hashing algorithms with the histogram of CVAs, called HCVA hashing. The histogram is first extracted from those angles that are in the biggest circle inscribed inside the normalized image. And then, it is compressed to make a short hash. We conducted some experiments to assess the performance, and illustrated that the DCT (Discrete Cosine Transform) is the best one of that cooperating with HCVA at generating hashes, as well as the HCVA hashing is robust and promising. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000436620600014
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Tang, Zhenjun                  0000-0003-3664-1363
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 79 条,共 322 条
标题: Generation of multi-wavelength femtosecond laser pulse based on nonlinear propagation of high peak power ultrashort laser pulse in single-mode fiber and spectral selectivity technology
作者: Lu, ZG (Lu Zhi-Guo); Yang, Z (Yang Zhi); Li, F (Li Feng); Li, QL (Li Qiang-Long); Wang, YS (Wang Yi-Shan); Yang, XJ (Yang Xiao-Jun)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 18 文献号: 184205 DOI: 10.7498/aps.67.20181026 出版年: SEP 20 2018
摘要: Highly-integrated high-reliability widely-tunable femtosecond laser sources have important application values in various research and application fields, such as ultrafast spectroscopy, quantum optics, remote sensing and bio-imaging. In multi-photon excited fluorescence microscopy, femtosecond laser sources with moderate pulse energy and wide wavelength tunable range can not only meet the application requirements of the different tissue structures for the peak power and excitation wavelength, but also improve the nonlinear fluorescence efficiency and imaging resolution of the sample, and thus enhancing the penetration depth. Considering the extensive application prospect and important scientific research significance of the widely tunable femtosecond laser, in this paper we conduct an experimental research of the high repetition rate multi-wavelength femtosecond laser generation in compact sized and low-cost configuration based on the nonlinear propagation scheme of the high peak power femtosecond laser pulses in single-mode fiber.
In experiment, we first construct a highly-integrated reliable all-polarization-maintaining fiber femtosecond laser amplifier, which mainly consists of an environmentally stable all-polarization-maintaining fiber mode-locked laser oscillator, single-mode fiber stretcher, a single-mode power pre-amplifier, a dual-cladding Yb-fiber amplifier, and transmission grating-pair compressor. Self-starting mode-locked operation is assured with a semiconductor saturable absorber mirror, and intra-cavity dispersion compensation is realized by a chirped fiber Bragg grating in the mode-locked oscillator. The mode-locked oscillator, which delivers laser pulses with center wavelength peaked at 1035 nm, is robust operation as temperature changes from 10 degrees C to 40 degrees C and the measured power fluctuation is less than 1% RMS over 168 hours at 23 degrees C. The amplified high repetition rate laser pulses are compressed in a double-pass 1000 lines/mm transmission grating-pair compressor. After compression, laser pulses with 5.83 W average power and 264 fs pulse duration at 34 MHz repetition rate can be obtained. Simultaneously, we also study the dependence of the compressed pulse duration on the amplified output power.
Employing a home-made high reliable compact sized all-polarization-maintaining fiber femtosecond laser as a pump source and low-cost single-mode fiber as a nonlinear medium, the generation technology of the widely tunable femtosecond laser in only fiber format is also studied based on the self-phase modulation nonlinear spectral broadening mechanism. Simultaneously, in order to reduce the effect of the dispersion on the spectral broadening as much as possible, an 80-mm-long fiber is used in experiment. The used single-mode spectral broadening fiber has a 6-mu m-diameter core and 20 fs(2)/mm dispersion coefficient. By coupling the femtosecond pump laser pulses into the 6-mu m-diameter fiber core, the output spectrum presents a significant nonlinear broadening. The coupled pump power can be continuously adjusted by a combination of a half-wave plate and a Glan laser polarizer. After bandpass filtering the leftmost and rightmost spectral lobes in self-phase modulation and self-steeping induced broadened spectrum with bandpass filters centered at 980, 1000, 1050, 1070 and 1100 nm, the laser pulses with 203, 195, 196, 187, and 194 fs pulse duration can be obtained at the corresponding center wavelengths.
The experimental scheme presented in this paper, which is based on the nonlinear spectral broadening of the high-reliability femtosecond laser pulse in single-mode fiber and the spectral selectivity technology, provides a new research approach to the realization of the highly-compacted reliable widely-tunable femtosecond laser sources and has important research significance.
入藏号: WOS:000445538300015
ISSN: 1000-3290
________________________________________
第 80 条,共 322 条
标题: Fabrication of a lightweight Al alloy mirror through 3D printing and replication methods
作者: Wang, YJ (Wang, Yongjie); Wu, XG (Wu, Xiaoge); Xu, L (Xu, Liang); Ding, JT (Ding, Jiaoteng); Ma, Z (Ma, Zhen); Xie, YJ (Xie, Yongjie)
来源出版物: APPLIED OPTICS 卷: 57 期: 27 页: 8096-8101 DOI: 10.1364/AO.57.008096 出版年: SEP 20 2018
摘要: In order to realize rapid fabrication of a lightweight mirror, an AlSi10Mg alloy mirror was made through 3D printing and replication methods. The mechanical, thermal, and physical properties, the surface accuracy, and the dimensional stability were investigated. Through a selective laser melting method, an Al alloy mirror was printed and exhibited a low areal density of 28.4 kg/m(2). Through replication, the mirror surface accuracy was improved to 0.033. (root mean square, lambda = 632.8 nm); surface roughness was 1.3 nm (Ra). The stability test result indicated that the 3D printed mirror presented good dimensional stability in air for a long time and in a temperature changing environment. (C) 2018 Optical Society of America
入藏号: WOS:000445075500058
PubMed ID: 30462083
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 81 条,共 322 条
标题: Ultra-low-loss double-cladding laser fiber fabricated by optimized chelate gas phase deposition technique
作者: She, SF (She, Shengfei); Li, WN (Li, Weinan); Chang, C (Chang, Chang); Li, Z (Li, Zhe); Zheng, JK (Zheng, Jinkun); Gao, S (Gao, Song); Zhang, Y (Zhang, Yan); Li, G (Li, Gang); Gao, Q (Gao, Qi); Zhao, W (Zhao, Wei); Zhao, BY (Zhao, Baoyin); Gu, HT (Gu, Haitao); Hou, CQ (Hou, Chaoqi)
来源出版物: APPLIED OPTICS 卷: 57 期: 27 页: 7943-7949 DOI: 10.1364/AO.57.007943 出版年: SEP 20 2018
摘要: By applying an optimized chelate gas phase deposition technique, a Yb/Ce codoped aluminosilicate fiber with ultra-low loss of 1.55 dB/km was successfully fabricated and reported. The fiber showed homogenous distribution of the refractive index and dopant concentration devoid of central dip and clustering. Using the fiber as the amplifier stage, it delivered 1023 W near-single-mode laser output (M-2 = 1.35) with a high slope efficiency of 85.1%, and the fiber temperature was less than 24.2 degrees C, primarily benefiting from the ultra-low background loss. The fiber also exhibited low photodarkening-induced loss, illustrating its outstanding photodarkening resistance. These results indicate that the ultra-low-loss Yb/Ce codoped aluminosilicate fiber is a prospective candidate for stable and reliable fiber laser applications. (C) 2018 Optical Society of America
入藏号: WOS:000445075500040
PubMed ID: 30462065
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 82 条,共 322 条
标题: Numerical calculation and experimental study on the small-size streak tube
作者: Tian, LP (Tian Li-Ping); Li, LL (Li Li-Li); Wen, WL (Wen Wen-Long); Wang, X (Wang Xing); Chen, P (Chen Ping); Lu, Y (Lu Yu); Wang, JF (Wang Jun-Feng); Zhao, W (Zhao Wei); Tian, JS (Tian Jin-Shou)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 18 文献号: 188501 DOI: 10.7498/aps.67.20180643 出版年: SEP 20 2018
摘要: The streak tube imaging lidar (STIL) community requires the streak tube with characteristics of small-size, high edge spatial resolution, high luminance gain, and large working area. In this work, with the aid of the computer simulation technology software, a streak camera with high edge spatial resolution and high luminance gain is designed, in which there are adopted 1) a spherical photocathode and screen to increase the edge spatial resolution and detection area, further enlarging the field of view for the STIL; 2) a slit accelerating electrode instead of the mesh one favorable for improving the electrical resistance and reliability for streak camera; 3) a streak tube with lower magnification combining with -15 kV working voltage to be able to achieve high luminance gain, thus further increasing the detection distance for STIL. Some static and dynamic properties of the tube are analyzed by observing different electron trajectories emitted from a number of different points on the photocathode. As for the spatial resolution, spatial modulation transfer function method is used to evaluate the spatial resolution characteristics of the streak tube. The 36.9 1p/mm at MTF = 5% in static mode and 23 1p/mm at MTF = 5% in dynamic mode of the high resolution across the 16 mm long slit on the photocathode can be obtained. As for the temporal resolution, three electron pulses at intervals of 54.6 ps can be well resolved by the streak tube in the dynamic mode. Thus, the temporal resolution of the streak tube is better than 54.6 ps. Furthermore, the influence of shape of the photocathode and screen on spatial resolution are analyzed. Compared with the P-streak tube (streak tube with plane photocathode and plane screen), S-streak tube (steak tube with spherical photocathode and spherical screen) can greatly improve the spatial resolution. The slit image of the spherical and plane photocathode are simulated. The spatial dispersion of the off-axis 8 mm slit image along the scanning direction is analyzed. The experimental results demonstrate that the spatial resolution of the small-size streak tube is 29.3 1p/mm at MTF = 5% over the whole working area 16 mm x 2 mm, and the luminance gain is higher than 39.4. The static spatial resolution of the small-size streak tube is much higher than 15 1p/mm at CTF = 11.64%; the dynamic spatial resolution is higher than 9.8 1p/mm at CTF = 5.51%; the temporal resolution is higher than 54.6 ps at T-screen = 4.3 ns and has good consistency on the whole photocathode, and the dynamic range is 345 : 1 at 54.6 ps. The streak camera contains 6 scanning levels for different depth of field and detection accuracy to achieve ultrafast signal diagnosis at different scanning speeds. The streak tube has a smaller dimension of Phi 40 mm x 140 mm It is of great significance in unmanned aerial and spaceborne laser imaging lidar detection.
入藏号: WOS:000445538300039
ISSN: 1000-3290
________________________________________
第 83 条,共 322 条
标题: Extension of water-window harmonic cutoff by laser defocusing-assisted phase matching
作者: Jin, C (Jin, Cheng); Chen, MC (Chen, Ming-Chang); Sun, HW (Sun, Hung-Wei); Lin, CD (Lin, C. D.)
来源出版物: OPTICS LETTERS 卷: 43 期: 18 页: 4433-4436 DOI: 10.1364/OL.43.004433 出版年: SEP 15 2018
摘要: We extend a recently demonstrated scheme [Optica 4, 976 (2017)] to overcome the limit of conventional harmonic cutoff for different pulse durations, laser wavelengths, and gas targets. By tuning the truncation of long wavelength lasers, we show that the defocusing-assisted phase matching (DAPM) can be achieved in a tightly focused beam and highly ionized short gas cell, and can be used to effectively extend the harmonic cutoff energy and optimize its yield. An analysis of phase matching reveals that at longer wavelengths, greater cutoff extension to the water window region is achieved because of the larger harmonic intrinsic phase (proportional to the cube of laser wavelength), and because DAPM works at relatively higher laser intensities using a Ne target. This scheme provides a promising method for efficiently generating intense attosecond light sources in the extreme ultraviolet to x-rays. (C) 2018 Optical Society of America
入藏号: WOS:000444400100031
PubMed ID: 30211883
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Lin, c d         D-7312-2012         0000-0003-4847-8938
Jin, Cheng         B-6479-2015         0000-0001-8445-2378
Sun, Hung-Wei                  0000-0002-6827-3844

ISSN: 0146-9592
eISSN: 1539-4794
________________________________________
第 84 条,共 322 条
标题: Optical thickness measurement with single-shot dual-wavelength in-line digital holography
作者: Min, JW (Min, Junwei); Zhou, ML (Zhou, Meiling); Yuan, X (Yuan, Xun); Wen, K (Wen, Kai); Yu, XH (Yu, Xianghua); Peng, T (Peng, Tong); Yao, BL (Yao, Baoli)
来源出版物: OPTICS LETTERS 卷: 43 期: 18 页: 4469-4472 DOI: 10.1364/OL.43.004469 出版年: SEP 15 2018
摘要: An algorithm for quantitative reconstruction of the optical thickness distribution of objects is proposed based on single-shot dual-wavelength in-line digital holography. Two single-wavelength holograms can be extracted from a single-shot recorded dual-wavelength in-line hologram. The quantitative optical thickness distribution of the specimen can be reconstructed directly without calculations of the phase images at every single wavelength. Thus, off-axis recording and phase-shifting operation are not required, enabling a fast and high-resolution measurement. The effectiveness and accuracy of the proposed method are verified by both numerical simulations and experimental results. (C) 2018 Optical Society of America
入藏号: WOS:000444400100040
PubMed ID: 30211892
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Xianghua                  0000-0002-7447-1396

ISSN: 0146-9592
eISSN: 1539-4794
________________________________________
第 85 条,共 322 条
标题: Assortative mixing in spatially-extended networks
作者: Makarov, VV (Makarov, Vladimir V.); Kirsanov, DV (Kirsanov, Daniil V.); Frolov, NS (Frolov, Nikita S.); Maksimenko, VA (Maksimenko, Vladimir A.); Li, XL (Li, Xuelong); Wang, Z (Wang, Zhen); Hramov, AE (Hramov, Alexander E.); Boccaletti, S (Boccaletti, Stefano)
来源出版物: SCIENTIFIC REPORTS 卷: 8 文献号: 13825 DOI: 10.1038/s41598-018-32160-4 出版年: SEP 14 2018
摘要: We focus on spatially-extended networks during their transition from short-range connectivities to a scale-free structure expressed by heavy-tailed degree-distribution. In particular, a model is introduced for the generation of such graphs, which combines spatial growth and preferential attachment. In this model the transition to heterogeneous structures is always accompanied by a change in the graph's degree-degree correlation properties: while high assortativity levels characterize the dominance of short distance couplings, long-range connectivity structures are associated with small amounts of disassortativity. Our results allow to infer that a disassortative mixing is essential for establishing long-range links. We discuss also how our findings are consistent with recent experimental studies of 2-dimensional neuronal cultures.
入藏号: WOS:000444571200033
PubMed ID: 30218078
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Frolov, Nikita         A-1166-2015         0000-0002-2788-1907
Li, Xuelong         Z-3785-2019         
Hramov, Alexander         C-5600-2008         0000-0003-2787-2530
Maksimenko, Vladimir A         F-5356-2017         0000-0002-4632-6896
Wang, Zhen         H-5017-2011         0000-0002-8182-2852
Frolov, Nikita         K-1487-2019         0000-0002-2788-1907
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2045-2322
________________________________________
第 86 条,共 322 条
标题: Effects of capacitance ratio on the image linearity of capacitive division image readout
作者: Lei, FP (Lei, Fanpu); Bai, YL (Bai, Yonglin); Zhu, BL (Zhu, Bingli); Wang, B (Wang, Bo); Bai, XH (Bai, Xiaohong); Hou, X (Hou, Xun)
来源出版物: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 卷: 902 页: 76-82 DOI:10.1016/j.nima.2018.06.030 出版年: SEP 11 2018
摘要: Capacitive division readout anode has the advantages of simple manufacture technology and high spatial resolution. Linearity of the restored image is limited by the relationship between the values of C (charge divide capacitor), C-s (parasitic capacitor), C-d (capacitor introduced by diagonal electrode) and C-p (perimeter capacitor). This paper describes a discrete capacitance matrix to investigate the dependence of image linearity on capacitor ratios, including C/C-s, C/C-d and(N-1)C/C-p (N is the number of nodes in each row of the capacitance matrix). Results presents that image nonlinearity varies monotonically with C/C-s, C/C-d and(N-1)C/C-p. The effect of these capacitors on the linearity of image can be negligible when C/C-s is greater than 100, C/C-d is greater than 10 and (N-1)C/C-p is smaller than 0.1. The reliability of the simulation results is verified by experiments. The RMS nonlinearity of capacitive anode is expected to less than 0.71%.
入藏号: WOS:000442082500010
ISSN: 0168-9002
eISSN: 1872-9576
________________________________________
第 87 条,共 322 条
标题: Adaptive Projected Matrix Factorization method for data clustering
作者: Chen, ML (Chen, Mulin); Wang, Q (Wang, Qi); Li, XL (Li, Xuelong)
来源出版物: NEUROCOMPUTING 卷: 306 页: 182-188 DOI: 10.1016/j.neucom.2018.04.031 出版年: SEP 6 2018
摘要: Data clustering aims to group the data samples into clusters, and has attracted many researchers in a variety of multidisciplinary fields, such as machine learning and data mining. In order to capture the geometry structure, many methods perform clustering according to a predefined affinity graph. So the clustering performance is largely determined by the graph quality. Unfortunately, the graph quality cannot be guaranteed in various real-world applications. In this paper, an Adaptive Projected Matrix Factorization (APMF) method is proposed for data clustering. Our contributions are threefold: (1) instead of keeping the graph fixed, graph learning is taken as a part of the clustering procedure; (2) the clustering is performed in the projected subspace, so the noise in the input data space is alleviated; (3) an efficient and effective algorithm is developed to solve the proposed problem, and its convergence is proved. Extend experiments on nine real-world benchmarks validate the effectiveness of the proposed method, and verify its superiority against the state-of-the-art competitors. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000433212700015
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Wang, Qi                  0000-0002-7028-4956
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 88 条,共 322 条
标题: Close-packed optical vortex lattices with controllable structures
作者: Li, XZ (Li, Xinzhong); Ma, HX (Ma, Haixiang); Zhang, H (Zhang, Hao); Tai, YP (Tai, Yuping); Li, HH (Li, Hehe); Tang, MM (Tang, Miaomiao); Wang, JG (Wang, Jingge); Tang, J (Tang, Jie); Cai, YJ (Cai, Yangjian)
来源出版物: OPTICS EXPRESS 卷: 26 期: 18 页: 22965-22975 DOI: 10.1364/OE.26.022965 出版年: SEP 3 2018
摘要: As a spatial structured light field, the optical vortex (OV) has attracted extensive attention in recent years. In practice. the OV lattice (OVL) is an optimal candidate for applications of orbital angular momentum (OAM)-based optical communications, microparticle manipulation, and micro/nanofabrication. However, traditional methods for producing OVLs meet a significant challenge: the OVL structures cannot be adjusted freely and form a close-packed arrangement, simultaneously. To overcome these difficulties, we propose an alternative scheme to produce close-packed OVLs (CPOVLs) with controllable structures. By borrowing the concept of the close-packed lattice from solid-state physics, CPOVLs with versatile structures are produced by using logical operations of expanding OV primitive cells combined with the technique of phase mask generation. Then, the existence of OAM states in the CPOVLs is verified. Furthermore, the energy flow and OAM distribution of the CPOVLs are visualized and analyzed. From a light field physics viewpoint, this work increases the adjustment dimensions and extends the fundamental understanding of the OVL, which will introduce novel applications. (C) 2018 optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000443431400051
PubMed ID: 30184953
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xinzhong         P-7966-2018         0000-0002-6426-4043
Ma, Haixiang                  0000-0001-9422-9372

ISSN: 1094-4087
________________________________________
第 89 条,共 322 条
标题: Subwavelength resolution Fourier ptychography with hemispherical digital condensers
作者: Pan, A (Pan, An); Zhang, Y (Zhang, Yan); Wen, K (Wen, Kai); Zhou, ML (Zhou, Meiling); Min, JW (Min, Junwei); Lei, M (Lei, Ming); Yao, BL (Yao, Baoli)
来源出版物: OPTICS EXPRESS 卷: 26 期: 18 页: 23119-23131 DOI: 10.1364/OE.26.023119 出版年: SEP 3 2018
摘要: Fourier ptychography (FP) is a promising computational imaging technique that overcomes the physical space-bandwidth product (SBP) limit of a conventional microscope by applying angular-varied illuminations. However, to date, the effective imaging numerical aperture (NA) achievable with a commercial LED board is still limited to the range of 0.3-0.7 with a 4 x /0.1NA objective due to the geometric constraint with the declined illumination intensities and attenuated signal-to-noise ratio (SNR). Thus the highest achievable half-pitch resolution is usually constrained between 500-1000 nm, which cannot meet the requirements of high-resolution biomedical imaging applications. Although it is possible to improve the resolution by using a high-NA objective lens, the FP approach is less appealing as the decrease of field-of-view (FOV) will far exceed the improvement of spatial resolution in this case. In this paper, we initially present a subwavelength resolution Fourier ptychography (SRFP) platform with a hemispherical digital condenser to provide high-angle programmable plane-wave illuminations of 0.95NA, attaining a 4 x /0.1NA objective with the final effective imaging performance of 1.05NA at a half-pitch resolution of 244 nm with the incident wavelength of 465 nm across a wide FOV of 14.60 mm(2), corresponding to a SBP of 245 megapixels. Our work provides an essential step of FP towards high-throughput imaging applications. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000443431400065
PubMed ID: 30184967
ISSN: 1094-4087
________________________________________
第 90 条,共 322 条
标题: Superpixel-Based Foreground Extraction With Fast Adaptive Trimaps
作者: Li, XL (Li, Xuelong); Liu, K (Liu, Kang); Dong, YS (Dong, Yongsheng)
来源出版物: IEEE TRANSACTIONS ON CYBERNETICS 卷: 48 期: 9 页: 2609-2619 DOI: 10.1109/TCYB.2017.2747143 出版年: SEP 2018
摘要: Extracting the foreground from a given complex image is an important and challenging problem. Although there have been many methods to perform foreground extraction, most of them are time-consuming, and the trimaps used in the matting step are labeled manually. In this paper, we propose a fast interactive foreground extraction method based on the superpixel GrabCut and image matting. Specifically, we first extract superpixels from a given image and apply GrabCut on them to obtain a raw mask. Due to that the resulting mask border is hard and toothing, we further propose fast and adaptive trimaps (FATs), and construct an FATs-based shared matting for computing a refined mask. Finally, by interactive processing, we can obtain the final foreground. Experimental results on the BSDS500 and alphamatting datasets demonstrate that our proposed method is faster than five representative methods, and performs better than the interactive representative methods in terms of the three evaluation criteria: 1) mean square error; 2) sum of absolute difference; and 3) execution time.
入藏号: WOS:000442362100009
PubMed ID: 28920912
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2168-2267
eISSN: 2168-2275
________________________________________
第 91 条,共 322 条
标题: Development of grid-reinforced carbon fiber mirrors using high-precision optical replication technology
作者: Xu, L (Xu, Liang); Wang, YJ (Wang, Yongjie); Ding, JT (Ding, Jiaoteng); Xie, YJ (Xie, Yongjie); Wu, XG (Wu, Xiaoge); Ma, Z (Ma, Zhen); Fan, XW (Fan, Xuewu)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 9 文献号: 093110 DOI: 10.1117/1.OE.57.9.093110 出版年: SEP 2018
摘要: Due to low density, high specific stiffness, and low thermal expansion, carbon fiber reinforced plastic (CFRP) is believed to be one of the potential material choices for optical mirrors. But CFRP is one of the two-phase materials that cannot be used as optical surface and must be surface modified. To develop one kind of grid-reinforced CFRP mirror, optical replication technology was used to modify and achieve high-precision surface, and theoretical deformation due to replica resin curing and deformation caused by laminates' manufacturing errors were studied in detail. Optical replication experiment has shown that lambda/20 root mean square high-precision surface can be achieved for Phi 100-mm grid-reinforced carbon fiber mirrors. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
入藏号: WOS:000449339000010
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 92 条,共 322 条
标题: Optical characteristics of an oxyfluoride glass waveguide formed by a proton implantation
作者: Wang, Y (Wang, Yue); Shen, Y (Shen, Yuan); Zheng, RL (Zheng, Rin-Lin); Shen, JP (Shen, Jian-Ping); Guo, HT (Guo, Hai-Tao); Liu, CX (Liu, Chun-Xiao)
来源出版物: RESULTS IN PHYSICS 卷: 10 页: 200-204 DOI: 10.1016/j.rinp.2018.06.001 出版年: SEP 2018
摘要: An optical waveguide was fabricated by H+ ion implantation with an energy of 400 keV and a dose of 8x10(16) ions/cm(2) in the oxyfluoride glass for the first time to the best of our knowledge. The dark mode spectra of the waveguide were measured by a prism coupling method before and after the thermal treatment. The number of modes was reduced after annealing. The implantation process of 400 keV H+ ions into the oxyfluoride glass was simulated by using the SRIM 2013 program. The refractive index distribution of the ion-implanted waveguide was reconstructed by the reflection calculation method. The refractive index was decreased in the waveguide region and there was an optical barrier with a reduced refractive index at the end of the ion range. The proton-implanted oxyfluoride glass waveguide is a desirable alternative for the fabrication of a compact optical integrated device.
入藏号: WOS:000443868900030
ISSN: 2211-3797
________________________________________
第 93 条,共 322 条
标题: Sub-Diffraction Visible Imaging Using Macroscopic Fourier Ptychography and Regularization by Denoising
作者: Li, ZX (Li, Zhixin); Wen, DS (Wen, Desheng); Song, ZX (Song, Zongxi); Liu, G (Liu, Gang); Zhang, WK (Zhang, Weikang); Wei, X (Wei, Xin)
来源出版物: SENSORS 卷: 18 期: 9 文献号: 3154 DOI: 10.3390/s18093154 出版年: SEP 2018
摘要: Imaging past the diffraction limit is of significance to an optical system. Fourier ptychography (FP) is a novel coherent imaging technique that can achieve this goal and it is widely used in microscopic imaging. Most phase retrieval algorithms for FP reconstruction are based on Gaussian measurements which cannot extend straightforwardly to long range, sub-diffraction imaging setup because of laser speckle noise corruption. In this work, a new FP reconstruction framework is proposed for macroscopic visible imaging. When compared with existing research, the reweighted amplitude flow algorithm is adopted for better signal modeling, and the Regularization by Denoising (RED) scheme is introduced to reduce the effects of speckle. Experiments demonstrate that the proposed method can obtain state-of-the-art recovered results on both visual and quantitative metrics without increasing computation cost, and it is flexible for real imaging applications.
入藏号: WOS:000446940600413
PubMed ID: 30231593
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Zhixin                  0000-0002-5462-4084

ISSN: 1424-8220
________________________________________
第 94 条,共 322 条
标题: Implementation of ultraviolet Thomson scattering on SG-III laser facility
作者: Zhao, H (Zhao, Hang); Li, ZC (Li, Zhichao); Yang, D (Yang, Dong); Jiang, XH (Jiang, Xiaohua); Liu, YG (Liu, Yonggang); Wang, F (Wang, Fang); Zhou, W (Zhou, Wei); Yan, YD (Yan, Yadong); He, JH (He, Junhua); Li, SW (Li, Sanwei); Guo, L (Guo, Liang); Peng, XS (Peng, Xiaoshi); Xu, T (Xu, Tao); Liu, SY (Liu, Shenye); Wang, F (Wang, Feng); Yang, JM (Yang, Jiamin); Jiang, SE (Jiang, Shaoen); Zheng, WG (Zheng, Wanguo); Zhang, BH (Zhang, Baohan); Ding, YK (Ding, Yongkun)
来源出版物: REVIEW OF SCIENTIFIC INSTRUMENTS 卷: 89 期: 9 文献号: 093505 DOI: 10.1063/1.5046837 出版年: SEP 2018
摘要: An ultraviolet Thomson-scattering system has been designed and implemented on the Shenguang-III laser facility, a 48-beam, 3 omega (351 nm), 180 kJ-level laser driver for high energy density physics and inertial confinement fusion researches. The 4 omega (263.3 nm) probe beam of the Thomson-scattering system is injected from the north pole (top) of the target chamber, with an assistant beam-pointing monitor to achieve high pointing accuracy. The Thomson-scattered light is collected by a double-Cassegrain optical transmission system, which provides an achromatic image over a wide wavelength range of 200-800 nm. A novel on-line alignment method is developed and applied to the diagnostic system, ensuring a volumetric positioning accuracy of similar to 30 mu m for the scattering volume. An online calibration is also conducted to provide the wavelength benchmark and the spectral resolution of the system. This Thomson-scattering system has been tested in a complicated experimental environment with gas-filled hohlraums, and a high-quality ion feature of the scattered light has been obtained. Published by AIP Publishing.
入藏号: WOS:000446159100037
PubMed ID: 30278718
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yang, Dong                  0000-0003-4245-7204
Zhao, Hang                  0000-0002-2356-367X

ISSN: 0034-6748
eISSN: 1089-7623
________________________________________
第 95 条,共 322 条
标题: Study on Terahertz and Infrared Characteristic Absorption Spectra of Solid-State Fructose
作者: Song, C (Song Chao); Ding, L (Ding Ling); Fan, WH (Fan Wen-hui)
来源出版物: SPECTROSCOPY AND SPECTRAL ANALYSIS 卷: 38 期: 9 页: 2700-2705 DOI: 10.3964/j.issn.1000-0593(2018)09-2700-06 出版年: SEP 2018
摘要: As a simple ketonic monosaccharide, fructose can be found in honey and many plants. Along with glucose and galactose, fructose is one of the three dietary monosaccharides and is usually bonded to glucose to form the disaccharide sucrose. Pure fructose is white crystal at room temperature and has been widely used in the food industry due to its high sweetness and low glycemic index. So far, studies on terahertz (THz) and infrared (IR) characteristics absorption spectra of the solid-state fructose are mostly confined to the simple measurement or theoretical calculation based on isolated-molecules calculation. Therefore, the THz spectra and IR spectra of solid-state fructose have been studied theoretically and experimentally in this paper. We reported the experimental absorption features of solid-state fructose beyond 3.0 THz for the first time to our knowledge. To reproduce the measured THz spectra and IR spectra of solid-state fructose, the theoretical calculations, such as MP2 and B3LYP based on isolated-molecules as well as PBE and PW91 based on unit cells, have been carried out, respectively. The calculated results showed that the PBE and PW91 calculations based on unit cells achieve better reproduction of absorption spectra of solid-state fructose than the MP2 and B3LYP calculations based on isolated-molecules, indicating the stronger influence of the intermolecular interactions for solid-state fructose compared to the intramolecular interactions for solid-state fructose, which reveals the significant effect of the surrounding environment on the vibration modes of solid-state fructose.
入藏号: WOS:000444933500007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Fan, Wen-Hui         M-1060-2018         0000-0003-2554-6723

ISSN: 1000-0593
________________________________________
第 96 条,共 322 条
标题: Optical Ridge Waveguides in Magneto-Optical Glasses Fabricated by Combination of Silicon Ion Implantation and Femtosecond Laser Ablation
作者: Zhu, QF (Zhu, Qi-Feng); Wang, Y (Wang, Yue); Shen, XL (Shen, Xiao-Liang); Guo, HT (Guo, Hai-Tao); Liu, CX (Liu, Chun-Xiao)
来源出版物: IEEE PHOTONICS JOURNAL 卷: 10 期: 5 文献号: 2400507 DOI: 10.1109/JPHOT.2018.2867491 出版年: SEP 2018
摘要: Tb3+-doped aluminum borosilicate glass is a promising magneto-optical material that can be used to fabricate Faraday rotating devices. In this paper, we report the fabrication of an optical ridge waveguide structure in the Tb3+-doped aluminum borosilicate glass by using a combination of femtosecond laser ablation and ion implantation. The end-face microscopic photographs of the waveguide were acquired by the optical microscope. The effective refractive indices of the modes and near-field intensity distributions were measured by the prism-coupling and end-face coupling techniques. The distributions of energy loss, refractive index, and light intensity were simulated by the stopping and range of ions in matter 2013, reflectivity calculation method, and finite-difference beam propagation method. The results provide a new idea for the fabrication of waveguide-type magneto-optical isolators.
入藏号: WOS:000444774900001
ISSN: 1943-0655
eISSN: 1943-0647
________________________________________
第 97 条,共 322 条
标题: Raman self-frequency-shift of soliton crystal in a high index doped silica micro-ring resonator [Invited]
作者: Lu, ZZ (Lu, Zhizhou); Wang, WQ (Wang, Weiqiang); Zhang, WF (Zhang, Wenfu); Liu, ML (Liu, Mulong); Wang, LR (Wang, Leiran); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Zhao, JG (Zhao, Jianguo); Xie, P (Xie, Peng); Wang, XY (Wang, Xinyu); Zhao, W (Zhao, Wei)
来源出版物: OPTICAL MATERIALS EXPRESS 卷: 8 期: 9 页: 2662-2669 DOI: 10.1364/OME.8.002662 出版年: SEP 1 2018
摘要: High index doped silica glass exhibiting low loss property and CMOS compatibility is a promising material in nonlinear optics. In this work, mode-locked soliton crystals (SCs) are demonstrated in a high-Q (>10(6)) micro-ring resonator (MRR) made in this platform. The asymmetric spectra of SCs are numerically investigated and interpreted as the combined impact of Raman self-frequency shift (RSFS) and the wavelength-dependent loss. By precisely comparing the experimental and simulated spectra based on the perturbed Lugiato-Lefever equation (LLE), the Raman shock time is inferred to be at the range of 2.5 fs to 2.7 fs for this material. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000443314600021
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507

ISSN: 2159-3930
________________________________________
第 98 条,共 322 条
标题: Low-threshold optical bistability in field-enhanced nonlinear guided-mode resonance grating nanostructure
作者: Ge, ZQ (Ge, Zhiqiang); Hei, XW (Hei, Xuwei); Wang, LR (Wang, Leiran); Sun, QB (Sun, Qibing); Si, JH (Si, Jinhai); Zhao, W (Zhao, Wei); Wang, GX (Wang, Guoxi); Zhang, WF (Zhang, Wenfu)
来源出版物: OPTICS LETTERS 卷: 43 期: 17 页: 4156-4159 DOI: 10.1364/OL.43.004156 出版年: SEP 1 2018
摘要: We have numerically studied the optical bistability in guided-mode resonance-assisted nonlinear grating nanostructure. A low-index slot is introduced to significantly improve the confinement of light in nonlinear material. In this way, the proposed novel configuration possesses low-threshold optical switching intensity (similar to 3 MW/cm(2)), which is about 58 times lower than that of typical nonlinear grating nanostructure without the low-index slot. This bistability study provides an effective method to reduce the threshold of optical switching intensity and thus can be applied in optical logic, optical computation, and all-optical memory. (C) 2018 Optical Society of America
入藏号: WOS:000443142900024
PubMed ID: 30160740
ISSN: 0146-9592
eISSN: 1539-4794
________________________________________
第 99 条,共 322 条
标题: Automatic Side Branch Ostium Detection and Main Vascular Segmentation in Intravascular Optical Coherence Tomography Images
作者: Cao, YH (Cao, Yihui); Jin, QH (Jin, Qinhua); Chen, YD (Chen, Yundai); Yin, QY (Yin, Qinye); Qin, XJ (Qin, Xianjing); Li, JA (Li, Jianan); Zhu, R (Zhu, Rui); Zhao, W (Zhao, Wei)
来源出版物: IEEE JOURNAL OF BIOMEDICAL AND HEALTH INFORMATICS 卷: 22 期: 5 页: 1531-1539 DOI: 10.1109/JBHI.2017.2771829 出版年: SEP 2018
摘要: Intravascular optical coherence tomography is the state-of-the-art imaging modality in percutaneous coronary interventionplanning and evaluation, in which side branch ostium and main vascular measurements play critical roles. However, manual measurement is time consuming and labor intensive. In this paper, we propose a fully automatic method for side branch ostium detection and main vascular segmentation to make up manual deficiency. In our method, side branch ostium points are first detected and subsequently used to divide the lumen contour into side branch and main vascular regions. Based on the division, main vascular contour is then smoothly fitted for segmentation. In side branch ostium detection, our algorithm creatively converts the definition of curvature into the calculation of the signed included angles in global view, and originally applies a differential filter to highlight the feature of side branch ostium points. A total of 4618 images from 22 pullback runs were used to evaluate the performance of the presented method. The validation results of side branch detection were TPR = 82.8%, TNR = 98.7%, PPV = 86.8%, NPV = 98.7%. The average ostial distance error (ODE) was 0.22 mm, and the DSC of main vascular segmentation was 0.96. In conclusion, the qualitative and quantitative evaluation indicated that the presented method is effective and accurate.
入藏号: WOS:000441795800020
PubMed ID: 29990134
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
chen, yundai         I-4353-2019         0000-0003-2252-8992
jin, qinhua                  0000-0001-6972-868X

ISSN: 2168-2194
________________________________________
第 100 条,共 322 条
标题: Dissipative soliton with sidebands on spectrum in an all-fibre laser
作者: Duan, LN (Duan, Lina); Zhang, T (Zhang, Ting); Wang, HS (Wang, Hushan); Wang, YS (Wang, Yishan); Li, Y (Li, Yan); Fu, HW (Fu, Haiwei)
来源出版物: LASER PHYSICS 卷: 28 期: 9 文献号: 095108 DOI: 10.1088/1555-6611/aacb4d 出版年: SEP 2018
摘要: We experimentally observed a dissipative soliton (DS) in an all-fiber laser with large-normal dispersion. The nonlinear polarization rotation (NPR) technique was used as the mode locker. The DS exhibited obvious sidebands on the spectrum, a feature that is distinctly different to that of the common DS previously reported. The spectral bandwidth was 57.43 nm, and the pulse duration was 2.20 ps. Remarkably, in the whole mode-locked pump regime, the DS remained in the single pulse state without multipulse shaping. Moreover, the pulse was compressed to similar to 140 fs by a negative dispersion device outside the cavity, and the pulse peak power reached 3.79 KW. We assumed that the spectral sidebands originated from the combined action of the nonlinear phase chirp and NPR-induced transmittance modulation, which may help to keep the mode-locked pulse working in the single pulse state. This work could help us gain a deeper insight into the DS formed in the normal dispersion regime.
入藏号: WOS:000439135800003
ISSN: 1054-660X
eISSN: 1555-6611
第 101 条,共 322 条
标题: Rapid generation of perfect vortex beam without side lobes
作者: Li, SQ (Li, Siqi); Liu, ML (Liu, Mulong); Li, XY (Li, Xingyi); Ge, ZQ (Ge, Zhiqiang); Zhang, LX (Zhang, Lingxuan)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 24 文献号: 1850289 DOI: 10.1142/S0217984918502895 出版年: AUG 30 2018
摘要: We have proposed an approach for rapid generation of perfect vortex beam without side lobes through a digital micromirror device (DMD). Employing this method, the amplitude and phase of far field can be controlled indirectly by changing the rotation state of each unit on the DMD. The perfect vortex beams of equal rings diameter independent of their topological charges are generated commendably and the side lobes are avoided. Moreover, we have demonstrated rapid switching among the generated orbital angular momentum modes at the speed of 10 kHz, which is much faster than that of the usual method realized by spatial light modulators (SLMs). The proposed method is very beneficial for the optical communication and trapping or manipulating the small particle based on orbital angular momentum modes.
入藏号: WOS:000442947300011
ISSN: 0217-9849
eISSN: 1793-6640
________________________________________
第 102 条,共 322 条
标题: Optimization of the probability of orbital angular momentum for Laguerre-Gaussian beam in Kolmogorov and non-Kolmogorov turbulence
作者: Yuan, YS (Yuan, Yangsheng); Liu, D (Liu, Dong); Zhou, ZX (Zhou, Zhengxian); Xu, HF (Xu, Huafeng); Qu, J (Qu, Jun); Cai, YJ (Cai, Yangjian)
来源出版物: OPTICS EXPRESS 卷: 26 期: 17 页: 21861-21871 DOI: 10.1364/OE.26.021861 出版年: AUG 20 2018
摘要: We derive the probabilities of the signal OAM state and crosstalk OAM state for a Laguerre-Gaussian (LG) beam propagating through Kolmogorov and Non-Kolmogorov turbulence, and derive the accurate analytical function of the probability for the received OAM state modulated by an arbitrary receiver aperture. The probability of the detected OAM state with a receiver aperture for different values of the radius is demonstrated numerically. Our numerical results show that the probability of the signal OAM state remains almost invariant when the radius of the receiver aperture varies. The probability of the crosstalk OAM state decreases with the decrease of the radius of the receiver aperture, thus it can be optimized by choosing a suitable value of the radius of the receiver aperture. Our results will be useful in free-space optical communications. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000442136200043
PubMed ID: 30130889
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Cai, Yangjian         E-9745-2012         0000-0003-3440-7709

ISSN: 1094-4087
________________________________________
第 103 条,共 322 条
标题: Four-wave mixing effect on high-power continuous-wave all-fiber lasers
作者: Zheng, JK (Zheng, Jinkun); Zhao, W (Zhao, Wei); Zhao, BY (Zhao, Baoyin); Li, Z (Li, Zhe); Li, G (Li, Gang); Gao, Q (Gao, Qi); Ju, P (Ju, Pei); Gao, W (Gao, Wei); She, SF (She, Shengfei); Wu, P (Wu, Peng)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 23 文献号: 1850275 DOI: 10.1142/S0217984918502755 出版年: AUG 20 2018
摘要: A four-wave mixing effect on high-power continuous-wave fiber lasers has been demonstrated theoretically and experimentally. Detailed theoretical description of phase matching is presented and we found that the phase matching condition is satisfied at the frequency shift of 5.16 THz. While the intensity in fiber core region is more than about 394 MW/cm(2), the four-wave mixing products of 1100 nm and 1060 nm were also observed in high-power all-fiber laser. The comparison shows that the experiment result is in good agreement with the simulation result. In addition, the beam quality deterioration for the laser is caused by the four-wave mixing effect and the mode instability. The M-2 factor measured at maximal intensity of 478 MW/cm(2) is 2.80.
入藏号: WOS:000442000600011
ISSN: 0217-9849
eISSN: 1793-6640
________________________________________
第 104 条,共 322 条
标题: Non-diffraction-length, tunable, Bessel-like beams generation by spatially shaping a femtosecond laser beam for high-aspect-ratio micro-hole drilling
作者: Yao, ZL (Yao, Zhulin); Jiang, L (Jiang, Lan); Li, XW (Li, Xiaowei); Wang, AD (Wang, Andong); Wang, Z (Wang, Zhi); Li, M (Li, Ming); Lu, YF (Lu, Yongfeng)
来源出版物: OPTICS EXPRESS 卷: 26 期: 17 页: 21960-21968 DOI: 10.1364/OE.26.021960 出版年: AUG 20 2018
摘要: Bessel beams are advantageous in high aspect-ratio microhole drilling because of their immunity to diffraction. However, conventional methods of generating Bessel beams result in poor adjustability of the nondiffraction length. In this study, we theoretically describe and experimentally demonstrate the generation of Bessel-like beams (BLBs) with an adjustable nondiffraction length by using a phase-only spatial light modulator. In this method, nondiffraction lengths varying from 10 to 35 mm can be achieved by changing the designed phase profile (curvature). High-quality, high aspect ratio (560:1) and length-adjustable microholes can be drilled by spatially shaping a femtosecond laser beam. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000442136200051
PubMed ID: 30130897
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
, Xiaowei                  0000-0003-1707-4957

ISSN: 1094-4087
________________________________________
第 105 条,共 322 条
标题: Improvement of the ionization factor in the quantitative rescattering theory for simulating macroscopic high-order harmonic generation
作者: Abro, N (Abro, Nazia); Wang, K (Wang, Kan); Zhu, XH (Zhu, Xinhao); Li, BC (Li, Baochang); Jin, C (Jin, Cheng)
来源出版物: PHYSICAL REVIEW A 卷: 98 期: 2 文献号: 023411 DOI: 10.1103/PhysRevA.98.023411 出版年: AUG 14 2018
摘要: We propose to correct the ionization factor in the quantitative rescattering (QRS) theory for a higher precision calculation of macroscopic high harmonic generation (HHG) in a gaseous medium. Compared to the first-order strong-field approximation (SFA-1) and the Ammosov-Delone-Krainov (ADK) ionization models, the Perelomov-Popov-Terent'ev (PPT) model achieves the best agreement with the macroscopic HHG spectra of Ar based on the solution of the time-dependent Schrodinger equation (TDSE). The investigation of the ionization probability dependence on laser intensity indicates that the PPT model is consistent with the TDSE, both in the tunneling and multiphoton ionization regimes, and the SFA-1 or the ADK mostly works in the tunneling regime. This explains the difference in the total macroscopic harmonic spectra, mainly due to off-axis harmonic emissions generated by small laser intensities. The examples for Ne and Xe by using three ionization models in the QRS theory also show the significance of ionization correction by the PPT model to precisely simulate the macroscopic HHG spectra. This study will help further increase the accuracy of simulating measured HHG spectra quantitatively under a variety of macroscopic conditions.
入藏号: WOS:000441668600007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Jin, Cheng         B-6479-2015         0000-0001-8445-2378

ISSN: 2469-9926
eISSN: 2469-9934
________________________________________
第 106 条,共 322 条
标题: On-chip optical isolator based on unidirectional wavelength-mode conversion waveguide
作者: Liu, WL (Liu, Wenlong); Liu, XB (Liu, Xuebin); Yan, QQ (Yan, Qiangqiang); Qiang, SM (Qiang, Simiao); Pi, HF (Pi, Haifeng); Hu, BL (Hu, Bingliang); Zhang, LX (Zhang, Lingxuan)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 22 文献号: 1850258 DOI: 10.1142/S0217984918502585 出版年: AUG 10 2018
摘要: Breaking Lorentz reciprocity is one necessary condition of optical isolator design. Unidirectional wavelength-mode conversion will be realized in a time-dependent system through a short operating range. Based on plasma dispersion effect, generate space-asymmetric periodical time-space modulation on silicon waveguide, and non-reciprocal propagation is realized in the waveguide. The designed unidirectional wavelength-mode conversion waveguide demonstrated that in the forward direction, input 1.55 mu m fundamental mode light signal and then output 1.5492 mu m is of 1st-order mode, while in the backward direction, input 1.5492 mu m is of 1st-order mode light signal and then output 1.5484 mu m is of fundamental mode. Based on this non-reciprocal structure, mode conversion waveguide and two-ring resonance filters were designed then, to accomplish on-chip optical isolation. The scale of the designed isolator is 160 mu m x 60 mu m, and the isolation is 21 dB, revealing perfect application potential.
入藏号: WOS:000440900800008
ISSN: 0217-9849
eISSN: 1793-6640
________________________________________
第 107 条,共 322 条
标题: Structure preserving unsupervised feature selection
作者: Lu, QM (Lu, Quanmao); Li, XL (Li, Xuelong); Dong, YS (Dong, Yongsheng)
来源出版物: NEUROCOMPUTING 卷: 301 页: 36-45 DOI: 10.1016/j.neucom.2018.04.001 出版年: AUG 2 2018
摘要: Spectral analysis was usually used to guide unsupervised feature selection. However, the performances of these methods are not always satisfactory due to that they may generate continuous pseudo labels to approximate the discrete real labels. In this paper, a novel unsupervised feature selection method is proposed based on self-expression model. Unlike existing spectral analysis based methods, we utilize self-expression model to capture the relationships between the features without learning the cluster labels. Specifically, each feature can be reconstructed by using a linear combination of all the features in the original feature space, and a representative feature should give a large weight to reconstruct other features. Besides, a structure preserved constraint is incorporated into our model for keeping the local manifold structure of the data. Then an efficient alternative iterative algorithm is utilized to solve our proposed model with the theoretical analysis on its convergence. The experimental results on different datasets show the effectiveness of our method.
入藏号: WOS:000432491500004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 108 条,共 322 条
标题: Video Synopsis in Complex Situations
作者: Li, XL (Li, Xuelong); Wang, ZG (Wang, Zhigang); Lu, XQ (Lu, Xiaoqiang)
来源出版物: IEEE TRANSACTIONS ON IMAGE PROCESSING 卷: 27 期: 8 页: 3798-3812 DOI: 10.1109/TIP.2018.2823420 出版年: AUG 2018
摘要: Video synopsis is an effective technique for surveillance video browsing and storage. However, most of the existing video synopsis approaches are not suitable for complex situations, especially crowded scenes. This is because these approaches heavily depend on the preprocessing results of foreground segmentation and multiple objects tracking, but the preprocessing techniques usually achieve poor performance in crowded scenes. To address this problem, we propose a comprehensive video synopsis approach which can be applied to scenes with drastically varying crowdedness. The proposed approach differs significantly from the existing methods, and has several appealing properties. First, we propose to detect the crowdedness of a given video, then, extract object tubes in sparse periods and extract video clips in crowded periods, respectively. Through such a solution, the poor performance of preprocessing techniques in crowded scenes can be avoided by extracting the whole video frames. Second, we propose a group-partition algorithm which can discovers the relationships among moving objects and alleviates several segmentation and tracking errors. Third, a group-based greedy optimization algorithm is proposed to automatically determine the length of a synopsis video. Besides, we present extensive experiments that demonstrate the effectiveness and efficiency of the proposed approach.
入藏号: WOS:000430967600010
PubMed ID: 29698210
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1057-7149
eISSN: 1941-0042
________________________________________
第 109 条,共 322 条
标题: Self-Weighted Supervised Discriminative Feature Selection
作者: Zhang, R (Zhang, Rui); Nie, FP (Nie, Feiping); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 8 页: 3913-3918 DOI: 10.1109/TNNLS.2017.2740341 出版年: AUG 2018
摘要: In this brief, a novel self-weighted orthogonal linear discriminant analysis (SOLDA) problem is proposed, and a self-weighted supervised discriminative feature selection (SSD-FS) method is derived by introducing sparsity-inducing regularization to the proposed SOLDA problem. By using the row-sparse projection, the proposed SSD-FS method is superior to multiple sparse feature selection approaches, which can overly suppress the nonzero rows such that the associated features are insufficient for selection. More specifically, the orthogonal constraint ensures the minimal number of selectable features for the proposed SSD-FS method. In addition, the proposed feature selection method is able to harness the discriminant power such that the discriminative features are selected. Consequently, the effectiveness of the proposed SSD-FS method is validated theoretically and experimentally.
入藏号: WOS:000439627700052
PubMed ID: 28910778
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Nie, Feiping         B-3039-2012         
Li, Xuelong         Z-3785-2019         
Zhang, Rui         U-4639-2017         0000-0001-9418-0863
Li, Xuelong                  0000-0002-0019-4197
Nie, Feiping                  0000-0002-0871-6519

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 110 条,共 322 条
标题: High-energy solitons generation with a nonlinear multimode interference-based saturable absorber
作者: Zhao, FY (Zhao, Fengyan); Wang, YS (Wang, Yishan); Wang, HS (Wang, Hushan); Hu, XH (Hu, Xiaohong); Zhang, W (Zhang, Wei); Zhang, T (Zhang, Ting); Cai, YJ (Cai, Yajun)
来源出版物: LASER PHYSICS 卷: 28 期: 8 文献号: 085104 DOI: 10.1088/1555-6611/aac538 出版年: AUG 2018
摘要: We demonstrate a mode-locked all-fiber Er-doped fiber laser using the structure of a step-index multimode fiber and a graded index fiber as a new saturable absorber (SA) based on nonlinear multimode interference. By bending the SA to a certain state, stable soliton pulses are obtained at a pump threshold of 65 mW. The oscillator generates soliton pulses at 1598 nm with a spectral bandwidth of 3.4 nm, 960 fs duration and a fundamental repetition rate of 9.789 MHz. The output power of 24 mW is achieved at the maximum pump power of 700 mW, corresponding to a single pulse energy of 2.44 nJ. To the best of our knowledge, this is the first time anyone has achieved the highest single pulse energy in a fiber laser with the SA at 1.5 mu m to date. Moreover, the impact of diverse mode field diameters of graded index fiber on mode-locking behavior will also be discussed.
入藏号: WOS:000435214000002
ISSN: 1054-660X
eISSN: 1555-6611
________________________________________
第 111 条,共 322 条
标题: Mid-infrared emissions of Dy3+ doped Ga-As-S chalcogenide glasses and fibers and their potential for a 4.2 mu m fiber laser
作者: Cui, J (Cui, Jian); Xiao, XS (Xiao, Xusheng); Xu, YT (Xu, Yantao); Cui, XX (Cui, Xiaoxia); Chen, ML (Chen, Meiling); Guo, JJ (Guo, Junjiang); Lu, M (Lu, Min); Peng, B (Peng, Bo); Guo, HT (Guo, Haitao)
来源出版物: OPTICAL MATERIALS EXPRESS 卷: 8 期: 8 页: 2089-2102 DOI: 10.1364/OME.8.002089 出版年: AUG 1 2018
摘要: For developing an ideal efficient and low-threshold medium for fiber lasers operated at 4 mu m wavebands, 0.05 wt.% to 0.5 wt.% Dy3+ ions doped Ga0.8As39.2S60 chalcogenide glasses were investigated and a 4.2 mu m fiber laser was theoretically studied based on the rate and propagation equations. It was shown that the Ga(0.8)AS(39.2)S(60) glass shows a desirable large Dy3+ ion solubility, which has been increased by an order of magnitude compared to As2S3 glass. Dy-rich nanocrystallines were found when the Dy3+ ions' concentration is more than 0.3wt.% (i.e. 3000 ppmw), and the concentration quenching was found based on spectral analysis: however, no rapid decreases in lifetimes were observed. 0.3wt.% Dy3+ doped Ga0.8As39.2S60 glass possesses relatively large laser quality factor sigma(emi) x tau(mea) = 1.70 x 10(-2)(3) cm(2).s and excellent thermal stability (Delta T = 182 degrees C), which can be successfully drawn into fibers indicating good potential for mid-infrared fiber laser. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000440471800005
ISSN: 2159-3930
________________________________________
第 112 条,共 322 条
标题: Decaying evolution dynamics of double-pulse mode-locking
作者: Wang, GM (Wang, Guomei); Chen, GW (Chen, Guangwei); Li, WL (Li, Wenlei); Zeng, C (Zeng, Chao); Yang, HR (Yang, Huiran)
来源出版物: PHOTONICS RESEARCH 卷: 6 期: 8 页: 825-829 DOI: 10.1364/PRJ.6.000825 出版年: AUG 1 2018
摘要: Taking advantage of the dispersive Fourier transformation technique, the decaying evolution processes of double-pulse mode-locking in a single-walled carbon-nanotube-based Er-doped fiber laser are observed in detail for the first time to our knowledge. The decaying dynamics of the double-pulse mode-locking state is analyzed in the spectral and temporal domains. We reveal that the two pulses in one cluster disappear either simultaneously or one by one during the decaying processes of double-pulse mode-locking states. In addition, the spectral evolution patterns of the special double-pulse states (i.e., bound states) are extremely distinct at different decline rates of the pump power. (C) 2018 Chinese Laser Press
入藏号: WOS:000440380100013
ISSN: 2327-9125
________________________________________
第 113 条,共 322 条
标题: An improved kinematic calibration method for serial manipulators based on POE formula
作者: Chang, CG (Chang, Chenguang); Liu, JG (Liu, Jinguo); Ni, ZY (Ni, Zhiyu); Qi, RL (Qi, Ruolong)
来源出版物: ROBOTICA 卷: 36 期: 8 页: 1244-1262 DOI: 10.1017/S0263574718000280 出版年: AUG 2018
摘要: Existing measurement equipments easily determine position with high precision. However, they evaluate orientation with low precision. It is necessary to minimize the effect of measurement error on identification accuracy. In this study, a method for kinematic calibration based on the product of exponentials (POE) is presented to improve the absolute positioning accuracy of a sliding manipulator. An error model with uniform and generic modeling rules is established in which the tool frame is selected as the reference frame. Furthermore, the redundant parameters of the error model are removed. Subsequently, the actual kinematic parameters are identified by using the least square method. Finally, the process of the improved method is discussed. Kinematic calibration simulations of a sliding manipulator are implemented. The results indicate that the proposed method significantly improves the precision of the sliding manipulator. The improved POE kinematic calibration method offers convenience, efficiency, and high precision. The proposed method can be applied to all types of serial robots with n-DOF.
入藏号: WOS:000437807400007
ISSN: 0263-5747
eISSN: 1469-8668
________________________________________
第 114 条,共 322 条
标题: 30 W all-fiber tunable, narrowband Yb-doped superfluorescent fiber source
作者: Wu, P (Wu, Peng); Zhao, BY (Zhao, Baoyin); Zhao, W (Zhao, Wei); Li, Z (Li, Zhe); Gao, W (Gao, Wei); Ju, P (Ju, Pei); Zheng, JK (Zheng, Jinkun); Wang, YS (Wang, Yishan)
来源出版物: INFRARED PHYSICS & TECHNOLOGY 卷: 92 页: 363-366 DOI: 10.1016/j.infrared.2018.06.032 出版年: AUG 2018
摘要: An all-fiber tunable, narrowband superfluorescent source is presented by using tunable seed source and two amplification stages. The output power reaches over 30 W with the tuning range of similar to 35 nm (from similar to 1045 to similar to 1080 nm) and the slope efficiency in the final amplifier is about 67%. At the maximum output power, the full width at half maximum is about 0.7 nm and the signal-noise ratio reaches over 25 dB. More output power can be realized by simply adding pump source. To the best of our knowledge, it is the first time to use all-fiber configuration to realize the tunable output at 1 mu m superfluorescent fiber source region.
入藏号: WOS:000443664600050
ISSN: 1350-4495
eISSN: 1879-0275
________________________________________
第 115 条,共 322 条
标题: Reduced graphene oxide as saturable absorbers for erbium-doped passively mode-locked fiber laser
作者: Chen, ZD (Chen, Zhen-Dong); Wang, YG (Wang, Yong-Gang); Li, L (Li, Lu); Lv, RD (Lv, Rui-Dong); Wei, LL (Wei, Liang-Lei); Liu, SC (Liu, Si-Cong); Wang, J (Wang, Jiang); Wang, X (Wang, Xi)
来源出版物: CHINESE PHYSICS B 卷: 27 期: 8 文献号: 084206 DOI: 10.1088/1674-1056/27/8/084206 出版年: AUG 2018
摘要: We demonstrate a nanosecond mode-locked erbium-doped fiber laser (EDFL) based on a reduced graphene oxide (RGO) saturable absorber (SA). The RGO SA is prepared by depositing the graphene oxide (GO) on fluorine mica through thermal reduction of GO. A scanning electron microscope (SEM), Raman spectrometer, and x-ray photoelectron spectroscopy (XPS) are adopted to analyze the RGO characteristics. The results show that the reduction degree of graphene oxide is very high. By embedding the RGO SA into the EDFL cavity, a stable mode-locked fiber laser is achieved with a central wavelength of 1567.29 nm and repetition rate of 12.66 MHz. The maximum output power and the minimum pulse duration are measured to be 18.22 mW and 1.38 ns respectively. As far as we know, the maximum output power of 18.22 mW is higher than those of other nanosecond mode-locked oscillators reported. Such a nanosecond pulse duration and megahertz repetition rate make this mode-locked erbium-doped fiber laser a suitable seed oscillator for high-power applications and chirped pulse amplifications.
入藏号: WOS:000442026600006
ISSN: 1674-1056
eISSN: 1741-4199
________________________________________
第 116 条,共 322 条
标题: Calibration and data restoration of light field modulated imaging spectrometer
作者: Su, LJ (Su, Li-Juan); Yan, QQ (Yan, Qiang-Qiang); Yuan, Y (Yuan, Yan); Wang, SF (Wang, Shi-Feng); Liu, YJ (Liu, Yu-Jian)
来源出版物: CHINESE PHYSICS B 卷: 27 期: 8 文献号: 080702 DOI: 10.1088/1674-1056/27/8/080702 出版年: AUG 2018
摘要: A light field modulated imaging spectrometer (LFMIS) can acquire the spatial-spectral datacube of targets of interest or a scene in a single shot. The spectral information of a point target is imaged on the pixels covered by a microlens. The pixels receive spectral information from different spectral filters to the diffraction and misalignments of the optical components. In this paper, we present a linear spectral multiplexing model of the acquired target spectrum. A calibration method is proposed for calibrating the center wavelengths and bandwidths of channels of an LFMIS system based on the liner-variable filter (LVF) and for determining the spectral multiplexing matrix. In order to improve the accuracy of the restored spectral data, we introduce a reconstruction algorithm based on the total least square (TLS) approach. Simulation and experimental results confirm the performance of the spectrum reconstruction algorithm and validate the feasibility of the proposed calibrating scheme.
入藏号: WOS:000442023600002
ISSN: 1674-1056
eISSN: 1741-4199
________________________________________
第 117 条,共 322 条
标题: 2D visualization of hot gas based on a mid-infrared molecular Faraday imaging filter
作者: Wu, KJ (Wu, Kuijun); Luo, ZG (Luo, Zhongjie); Feng, YT (Feng, Yutao); Yu, GB (Yu, Guangbao); Liu, LM (Liu, Linmei); Xiong, YH (Xiong, Yuanhui); Li, FQ (Li, Faquan)
来源出版物: OPTICS LETTERS 卷: 43 期: 15 页: 3686-3689 DOI: 10.1364/OL.43.003686 出版年: AUG 1 2018
摘要: This Letter presents recent results on, to the best of our knowledge, the first experimental demonstration of a mid-infrared molecular Faraday imaging filter (MOFIF)-based camera for hot gas visualization. Gas-phase nitric oxide (NO) is used as the working material of the MOFIF due to the fact that NO is the typical representative of the para- magnetic species and plays an important role in the chemical and physical process of combustion reaction. The MOFIF transmission with comb-like transmittance spectrum is elaborately designed and matches well with the radiation spectrum of NO gas. Pure NO infrared images have been well captured in a combustion environment, and shown as a video that demonstrates the imaging capability and gas selectivity of MOFIF. (C) 2018 Optical Society of America
入藏号: WOS:000440405900058
PubMed ID: 30067655
ISSN: 0146-9592
eISSN: 1539-4794
________________________________________
第 118 条,共 322 条
标题: System design of an optical interferometer based on compressive sensing
作者: Liu, G (Liu, Gang); Wen, DS (Wen, De-Sheng); Song, ZX (Song, Zong-Xi)
来源出版物: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 卷: 478 期: 2 页: 2065-2073 DOI: 10.1093/mnras/sty1167 出版年: AUG 2018
摘要: In this paper, we develop a new optical interferometric telescope architecture based on compressive sensing (CS) theory. Traditional optical telescopes with large apertures must be large in size, heavy and have high-power consumption, which limits the development of space-based telescopes. A turning point has occurred in the advent of imaging technology that utilizes Fourier-domain interferometry. This technology can reduce the system size, weight and power consumption by an order of magnitude compared to traditional optical telescopes at the same resolution. CS theory demonstrates that incomplete and noisy Fourier measurements may suffice for the exact reconstruction of sparse or compressible signals. Our proposed architecture combines advantages from the two frameworks, and the performance is evaluated through simulations. The results indicate the ability to efficiently sample spatial frequencies, while being lightweight and compact in size. Another attractive property of our architecture is the strong denoising ability for Gaussian noise.
入藏号: WOS:000439547400051
ISSN: 0035-8711
eISSN: 1365-2966
________________________________________
第 119 条,共 322 条
标题: Performance Comparison of All-Optical Amplify-and-Forward Relaying FSO Communication Systems With OOK and DPSK Modulations
作者: Huang, XN (Huang, Xinning); Xie, XP (Xie, Xiaoping); Song, JZ (Song, Jiazheng); Duan, T (Duan, Tao); Hu, H (Hu, Hui); Xu, X (Xu, Xin); Su, YL (Su, Yulong)
来源出版物: IEEE PHOTONICS JOURNAL 卷: 10 期: 4 文献号: 7905411 DOI: 10.1109/JPHOT.2018.2852301 出版年: AUG 2018
摘要: All-optical amplify-and-forward (OAF) relaying technique can amplify and filter the attenuated optical signal in optical domain, and thus is regarded as a simple way to extend the transmission distance of free-space optical (FSO) communication systems. At the relaying node, however, the incident background radiation and the amplified spontaneous emission noise of the deployed erbium-doped fiber amplifier will deteriorate the optical signal-to-noise, therefore causing the degradation of the system's bit error ratio (BER). In this paper, we performsimulations and experiments on FSO system with on-off keying (OOK) and differential phase-shift keying (DPSK) signals, focusing on the receiving sensitivity loss (RSL) of the OAF-assisted dual-hop system. Taking the BER level of 10(-7) as the reference, we find that the DPSK system suffers more than 8 dB RSL at the data rate of 5 Gb/s in simulation, while the OOK system gets less than 1 dB RSL at the same data rate. In the following experiments, the obtained results exhibit that RSL of DPSK system is nearly 10 dB, which of OOK system is less than 1.5 dB, shown similarly property to the simulations.
入藏号: WOS:000439348800001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Xinning                  0000-0002-0610-4551

ISSN: 1943-0655
eISSN: 1943-0647
________________________________________
第 120 条,共 322 条
标题: Impact of two-photon absorption and free-carrier effects on times lens based on four-wave mixing in silicon waveguides
作者: Xie, P (Xie, Peng); Sun, QB (Sun, Qibing); Wang, LR (Wang, Leiran); Wen, Y (Wen, Yu); Wang, XY (Wang, Xinyu); Wang, GX (Wang, Guoxi); Zeng, C (Zeng, Chao); Liu, ML (Liu, Mulong); Ge, ZQ (Ge, Zhiqiang); Lu, ZZ (Lu, Zhizhou)
来源出版物: APPLIED PHYSICS EXPRESS 卷: 11 期: 8 文献号: 082204 DOI: 10.7567/APEX.11.082204 出版年: AUG 2018
摘要: We investigate the influences of two-photon absorption (TPA) and free-carrier effects on a time lens via four-wave mixing in silicon waveguides. It is found that the output waveform is severely modulated arid the conversion efficiency is sharply reduced in temporal imaging owing to the impacts of the nonlinear absorption. A silicon-organic hybrid slot waveguide with negligible TPA is proposed for the time lens, which could realize 600x magnification of femtosecond pulses. These results can increase the signal bandwidth from gigahertz to terahertz and give rise to important potential applications for ultrafast optical signal processing in integrated optics, uitrafast optics, and optical communications. (C) 2018 The Japan Society of Applied Physics
入藏号: WOS:000438502600001
ISSN: 1882-0778
eISSN: 1882-0786
________________________________________
第 121 条,共 322 条
标题: Star Map Stitching Algorithm Based on Visual Principle
作者: Qiu, S (Qiu, Shi); Zhou, DM (Zhou, Dongmei); Guo, Q (Guo, Qiang); Qin, HL (Qin, Hanlin); Yan, X (Yan, Xiang); Yang, JL (Yang, Jinlong)
来源出版物: INTERNATIONAL JOURNAL OF PATTERN RECOGNITION AND ARTIFICIAL INTELLIGENCE 卷: 32 期: 8 文献号: 1850028 DOI: 10.1142/S0218001418500283 出版年: AUG 2018
摘要: For the problem that the limited star map field angle cannot obtain the complete star map accurately, the paper study astral intrinsic and imaging features, a star map stitching algorithm based on the principle of visual perception is proposed firstly. The matching models of time and space dimensions is constructed by simulating the visual perception, then the stars and the planets points are saved by searching the matching star group dynamically, the star map is stitched and reconstructed efficiently by creating the computer sparse storage model. The experimental results show that the algorithm can achieve data compression quickly, compression ratio is 99.54%, which can reduce complexity of manual processing and can achieve star map stitching accurately.
入藏号: WOS:000429438300004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Guo, Qiang         I-2949-2019         

ISSN: 0218-0014
eISSN: 1793-6381
________________________________________
第 122 条,共 322 条
标题: Large-area single photon compressive imaging based on multiple micro-mirrors combination imaging method
作者: Yan, QR (Yan, Qiu-Rong); Wang, H (Wang, Hui); Yuan, CL (Yuan, Cheng-Long); Li, B (Li, Bing); Wang, YH (Wang, Yu-Hao)
来源出版物: OPTICS EXPRESS 卷: 26 期: 15 页: 19080-19090 DOI: 10.1364/OE.26.019080 出版年: JUL 23 2018
摘要: We demonstrate a single photon compressive imaging system with the image plane up to the entire digital micro-mirror device (DMD) work area. A parallel light source is designed to reduce the influence of light scattering on imaging resolution and a photon counting photomultiplier tube (PMT) with a large photosensitive area is used to effectively collect light reflected from the full screen of DMD. A control and counting circuit, based on Field-Programmable Gate Array (FPGA), is developed to load binary random matrix into the DMD controller for each measurement, and to count single-photon pulse output from PMT simultaneously. To reduce imaging time and huge memory occupation for image reconstruction, a multiple micro-minors combination imaging method is proposed. The signalto-noise ratio and detection limit of the imaging system is theoretically deduced. Theoretical analysis and experimental results show that micro-mirrors combination imaging method is more suitable for faster imaging in a weaker-light-level environment. In order to achieve high imaging quality, the size of the combined pixels and the average time of each measurement should be moderate, so that the impact of Poisson shot noise is minimized. (C) 2018 Optical Society of America under the terms of the OSA Opal Access Publishing Agreement
入藏号: WOS:000439472400027
PubMed ID: 30114168
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wang, Yuhao         O-9322-2019         0000-0002-8445-0361

ISSN: 1094-4087
________________________________________
第 123 条,共 322 条
标题: Spectrum reconstruction in Fourier transform imaging spectroscopy based on high-performance parallel computing
作者: Zhang, WK (Zhang, Weikang); Wen, DS (Wen, Desheng); Song, ZX (Song, Zongxi); Liu, G (Liu, Gang); Wei, X (Wei, Xin); Li, ZX (Li, Zhixin)
来源出版物: APPLIED OPTICS 卷: 57 期: 21 页: 5983-5991 DOI: 10.1364/AO.57.005983 出版年: JUL 20 2018
摘要: In this paper, parallel-processing algorithms for spectrum reconstruction in Fourier transform imaging spectroscopy are proposed using high-performance parallel computing. Because of the huge amount of interference data, traditional algorithms are inefficient and time-consuming. It is necessary to process interference data as soon as possible to form spectral data for research and economy. We take advantage of parallel computing based on the graphics processing unit (CPU) to enable higher efficiency and reduced operation time. Furthermore, traditional algorithms for processing interferograms on the central processing unit are introduced for comparison. The experimental results show that the runtime is reduced from 1.144 to 0.332 ms using our parallel algorithms, and for the huge amount of data, the designed parallel-processing mechanism on the GPU has advantages over the traditional pipeline. (C) 2018 Optical Society of America
入藏号: WOS:000439397300012
PubMed ID: 30118023
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zhang, Weikang                  0000-0003-2279-3294

ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 124 条,共 322 条
标题: A reduced-order approach to the adaptive fuzzy sliding mode control o the constrained manipulator
作者: Liang, YB (Liang, Yanbing); Shi, H (Shi, Heng); Tian, GY (Tian, Guangyuan)
来源出版物: ADVANCES IN MECHANICAL ENGINEERING 卷: 10 期: 7 文献号: 1687814018786791 DOI: 10.1177/1687814018786791 出版年: JUL 19 2018
摘要: A reduced-order approach to the adaptive fuzzy sliding mode control of the constrained manipulator is proposed. Based on the Udwadia-Kalaba motion constraint equation, the dynamic equation of the constrained manipulator with both ideal and non-ideal constraints is obtained. Considering the uncertainty of the terminal non-ideal constrained force and the chattering phenomenon of sliding mode control, the adaptive fuzzy and the sliding mode control method are combined to control the constrained manipulator. Because the system is constrained, the model order reduction method is innovatively used in the control algorithm. The stability of the system is proved by Lyapunov theorem. For demonstrating the effectiveness of the control algorithm, the 2-degree-of-freedom manipulator is taken as the research object. Finally, the high-precision control of the manipulator is achieved and the chattering phenomenon caused by the sliding mode control is weakened.
入藏号: WOS:000444569700001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Shi, Heng                  0000-0003-4362-2347

ISSN: 1687-8132
eISSN: 1687-8140
________________________________________
第 125 条,共 322 条
标题: Stabilized Optoelectronic Oscillator With Enlarged Frequency-Drift Compensation Range
作者: Dai, J (Dai, Jian); Zhao, ZY (Zhao, Ziyan); Zeng, Y (Zeng, Yao); Liu, JL (Liu, Jingliang); Liu, AN (Liu, Anni); Zhang, T (Zhang, Tian); Yin, FF (Yin, Feifei); Zhou, Y (Zhou, Yue); Liu, YN (Liu, Yuanan); Xu, K (Xu, Kun)
来源出版物: IEEE PHOTONICS TECHNOLOGY LETTERS 卷: 30 期: 14 页: 1289-1292 DOI: 10.1109/LPT.2018.2844333 出版年: JUL 15 2018
摘要: To improve the frequency-drift compensation range for the stabilized optoelectronic oscillator, a novel stabilization scheme based on the frequency conversion pair has been proposed and experimentally demonstrated. The cavity length is adjusted by controlling the phase shift of oscillation signal at relatively low frequency via frequency division and frequency multiplication. In the proof-of-concept experiment, a 10-GHz signal has been successfully generated with the phase noise about -123 dBc/Hz at 10-kHz offset frequency assisted by the external triggering. The optoelectronic resonant cavity is tuned at 5 GHz via a divide-by-2 prescaler and a frequency doubler, and the frequency compensation range can be enlarged more than three times compared with a conventional phase-locked-loop-based stabilization method. Finally, the stability of the locked optoelectronic oscillator is improved from 4.1 x 10(-7) to 1.1 x 10(-10) at 1000-s averaging time.
入藏号: WOS:000436941200005
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Liu, Jingliang                  0000-0001-8165-7079

ISSN: 1041-1135
eISSN: 1941-0174
________________________________________
第 126 条,共 322 条
标题: Extreme-constrained spatial-spectral corner detector for image-level hyperspectral image classification
作者: Li, YS (Li, Yanshan); Xu, JJ (Xu, Jianjie); Xia, RJ (Xia, Rongjie); Huang, QH (Huang, Qinghua); Xie, WX (Xie, Weixin); Li, XL (Li, Xuelong)
来源出版物: PATTERN RECOGNITION LETTERS 卷: 109 特刊: SI 页: 110-119 DOI: 10.1016/j.patrec.2018.03.022 出版年: JUL 15 2018
摘要: As one type of local invariant feature, corner feature plays an important role in diverse applications such as: video mining, target detection, image classification, image retrieval, and image matching, etc. However, there are few studies on corner feature for hyperspectral image (HSI). Therefore, this paper proposes a novel corner feature for HSI named extreme-constrained spatial-spectral corner (ECSSC for short) and its corresponding detector. The definition of ECSSC is developed based on the definition of spectral-spatial interest point and the characteristic of HSI. Based on this definition, the detector of ECSSC is put forward and introduced in detail. Then, as an important application of ECSSC, an efficient framework for image-level HSI classification is designed based on ECSSC and parallel computation. The experimental results show that the proposed algorithm can detect abundant corner features with high repeatability rate from HSI and the accuracy of image-level HSI based on ECSSC is dramatically higher than that of the state of the art.
(C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000434380800015
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0167-8655
eISSN: 1872-7344
________________________________________
第 127 条,共 322 条
标题: Inter-layer competition in adaptive multiplex network
作者: Pitsik, E (Pitsik, Elena); Makarov, V (Makarov, Vladimir); Kirsanov, D (Kirsanov, Daniil); Frolov, N (Frolov, Nikita); Goremyko, M (Goremyko, Mikhail); Li, XL (Li, Xuelong); Wang, Z (Wang, Zhen); Hramov, A (Hramov, Alexander); Boccaletti, S (Boccaletti, Stefano)
来源出版物: NEW JOURNAL OF PHYSICS 卷: 20 文献号: 075004 DOI: 10.1088/1367-2630/aad00d 出版年: JUL 12 2018
摘要: We consider competition between layers in adaptive multiplex networks of phase oscillators, where adaptation principles (which cause intra-layer topology evolution) are inspired by real world homophily and homeostasis phenomena. Our model yields the emergence of both scale-free topologies and meso-scale structures in the layers, for an appropriate choice of the control parameters. We further report that the growth of the number of interacting layers leads to a decrease of the global order, due to inter-layer structural competition. However, the increase of the system's scale can effect local synchronization between neighboring (or strongly coupled) nodes. Such unforeseen phenomena is connected with the nature of the competitive mechanism, which implies the rivalry for optimal structure within the whole system, a situation occurring in a variety of natural systems.
入藏号: WOS:000438672500001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Hramov, Alexander         C-5600-2008         0000-0003-2787-2530
Wang, Zhen         H-5017-2011         0000-0002-8182-2852
Li, Xuelong         Z-3785-2019         
Frolov, Nikita         K-1487-2019         0000-0002-2788-1907
Frolov, Nikita         A-1166-2015         0000-0002-2788-1907
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1367-2630
________________________________________
第 128 条,共 322 条
标题: Real-Time Observation of the Buildup of Soliton Molecules
作者: Liu, XM (Liu, Xueming); Yao, XK (Yao, Xiankun); Cui, YD (Cui, Yudong)
来源出版物: PHYSICAL REVIEW LETTERS 卷: 121 期: 2 文献号: 023905 DOI: 10.1103/PhysRevLett.121.023905 出版年: JUL 12 2018
摘要: Real-time spectroscopy access to ultrafast fiber lasers opens new opportunities for exploring complex soliton interaction dynamics. Here, we have reported the first observation, to the best of our knowledge, of the entire buildup process of soliton molecules (SMs) in a mode-locked laser. We have observed that the birth dynamics of a stable SM experiences five different stages, i.e., the raised relaxation oscillation (RO) stage, beating dynamics stage, transient single pulse stage, transient bound state, and finally the stable bound state. We have discovered that the evolution of pulses in the raised RO stage follows a law that only the strongest one can ultimately survive and, meanwhile, the pulses periodically appear at the same temporal positions for all lasing spikes during the same RO stage (named as memory ability) but they lose such ability between different RO stages. Moreover, we have found that the buildup dynamics of SMs is quite sensitive to both the polarization state of intracavity light and the fluctuation of pump power. These results provide new perspectives into the ultrafast transient process in mode-locked lasers and the dynamics of complex nonlinear systems.
入藏号: WOS:000438351300010
PubMed ID: 30085749
ISSN: 0031-9007
eISSN: 1079-7114
________________________________________
第 129 条,共 322 条
标题: Thermally induced chirp studies on spectral broadening of semiconductor laser diode arrays
作者: Zhang, HY (Zhang, Hongyou); Jia, YT (Jia, Yangtao); Zah, CE (Zah, Chung-En); Liu, XS (Liu, Xingsheng)
来源出版物: APPLIED OPTICS 卷: 57 期: 20 页: 5599-5603 DOI: 10.1364/AO.57.005599 出版年: JUL 10 2018
摘要: Spectral-width broadening has many factors. Diode lasers are not always monochromatic due to several broadening mechanisms, widening the energy distribution of emitted photons. In this paper, we report the two main factors affecting time average spectral-width broadening of a laser diode array (LDA)-a transient rise of the active region temperature of an LDA due to injection current, and the temperature and stress nonuniform distribution of different emitters within an LDA. We find that temperature and stress nonuniformity broadens the spectral width by almost 0.1-1.0 nm as a function of different operating conditions, while the thermally induced chirp that is attributed to injection current plays a more signification role in spectral-width broadening. (C) 2018 Optical Society of America
入藏号: WOS:000438315500008
PubMed ID: 30118070
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
ZAH, CHUNG-EN         R-3016-2019         
ZHANG, Hongyou                  0000-0001-5776-0025

ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 130 条,共 322 条
标题: Single-shot time-gated fluorescence lifetime imaging using three-frame images
作者: Li, YH (Li, Yahui); Jia, H (Jia, Hui); Chen, SR (Chen, Shaorong); Tian, JS (Tian, Jinshou); Liang, LL (Liang, Lingliang); Yuan, FF (Yuan, Fenfang); Yu, HQ (Yu, Hongqi); Li, DDU (Li, David Day-Uei)
来源出版物: OPTICS EXPRESS 卷: 26 期: 14 页: 17936-17947 DOI: 10.1364/OE.26.017936 出版年: JUL 9 2018
摘要: Qualitative and quantitative measurements of complex flows demand for fast single-shot fluorescence lifetime imaging (FLI) technology with high precision. A method, single-shot time-gated fluorescence lifetime imaging using three-frame images (TFI-TGFLI), is presented. To our knowledge, it is the first work to combine a three-gate rapid lifetime determination (RLD) scheme and a four-channel framing camera to achieve this goal. Different from previously proposed two-gate RLD schemes, TFI-TGFLI can provide a wider lifetime range 0.6 similar to 13ns with reasonable precision. The performances of the proposed approach have been examined by both Monte-Carlo simulations and toluene seeded gas mixing jet diagnosis experiments. The measured average lifetimes of the whole excited areas agree well with the results obtained by the streak camera, and they are 7.6ns (N-2 = 7L/min; O-2 < 0.1L/min) and 2.6ns (N-2 = 19L/min; O-2 = 1L/min) with the standard deviations of 1.7ns and 0.8ns among the lifetime image pixels, respectively. The concentration distributions of the quenchers and fluorescent species were further analyzed, and they are consistent with the experimental settings. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000438209100027
PubMed ID: 30114076
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, David                  0000-0002-6401-4263

ISSN: 1094-4087
________________________________________
第 131 条,共 322 条
标题: Design, analysis of self-configurable modular adjustable latch lock for segmented space mirrors
作者: Li, XP (Li, Xupeng); Wang, W (Wang, Wei); Shi, JF (Shi, Jinfeng); Wang, CC (Wang, Chenchen); Zhao, H (Zhao, Hui); Fan, XW (Fan, Xuewu)
来源出版物: OPTICS EXPRESS 卷: 26 期: 14 页: 18064-18081 DOI: 10.1364/OE.26.018064 出版年: JUL 9 2018
摘要: This paper presents a connection mechanism for autonomous self-assembly of segmented space mirrors. Using this connection mechanism, space mirrors can be autonomously captured, positioned, locked and adjusted. The purpose of assembling space mirrors on orbit is to overcome the limits of launch volume and mass and provide a feasibility for future extremely large space telescope in order to improve optical performance to function as monolithic mirrors. In this paper, first, the design details and operation principle of the connection mechanism are presented. Then, based on the initial capture conditions, a doublecontact model is investigated. And simulated results of the dynamic and optical performance show that the proposed mechanism overcomes significant alignment errors and is considered suitable for space optical system. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.
入藏号: WOS:000438209100037
PubMed ID: 30114085
ISSN: 1094-4087
________________________________________
第 132 条,共 322 条
标题: Axial multi-particle trapping and real-time direct observation
作者: Wang, Y (Wang Yue); Liang, YS (Liang Yan-Sheng); Yan, SH (Yan Shao-Hui); Cao, ZL (Cao Zhi-Liang); Cai, YN (Cai Ya-Nan); Zhang, Y (Zhang Yan); Yao, BL (Yao Bao-Li); Lei, M (Lei Ming)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 13 文献号: 138701 DOI: 10.7498/aps.67.20180460 出版年: JUL 5 2018
摘要: The optical tweezers with the special advantages of non-mechanical contact and the accurate measurement of positions of particles, are a powerful manipulating tool in numerous applications such as in colloidal physics and life science. However, the standard optical tweezers system uses a single objective lens for both trapping and imaging. As a result, the trapping and imaging regions are confined to the volume near the focal plane of the objective lens, making it difficult to track the trapped particles arranged in the axial direction. Therefore, multiple trapping along axial direction remains a challenge. The three-dimensional imaging technology can realize the monitoring of the axial plane, but neither the laser scanning microscopy nor the wide-field imaging technology can meet the requirement of the real-time imaging. To address this issue, we propose a modified axial-plane Gerchberg-Saxton (GS) iterative algorithm based on the Fourier transform in the axial plane. Compared with the direct algorithm such as the Fresnel lens method, the modified axial-plane GS iterative algorithm has a higher modulation efficiency, and the generated axial distribution has a sharper intensity. In theory, the traps generated each have an ideal Gaussian intensity distribution independently, which is proved by the simulation of reconstructed field. With such an iterative algorithm, we can directly create multiple point-trap array arranged along the axial direction. We also develop an axial-imaging scheme. In this scheme, the particles are trapped and a right-angled silver-coated 45 degrees reflector is used to realize axial-plane imaging. The scheme is verified by imaging silica particles in an axial plane and a lateral plane simultaneously. Furthermore, we combine the axial-plane imaging technique with holographic optical tweezers, and demonstrate the simultaneous optical trapping in 2 x 2 trap array and the monitoring of multiple silica particles in the axial plane. The trap stiffness of traps array in axial plane is calibrated by measuring the Brownian motion of the trapped particles in the axial trap array with digital video microscopy. The proposed technique provides a new perspective for optical micromanipulation, and enriches the functionality of optical micromanipulation technology, and thus it will have many applications in biological and physical research.
入藏号: WOS:000443198700030
ISSN: 1000-3290
________________________________________
第 133 条,共 322 条
标题: An Early Study on Imaging 3D Objects Hidden Behind Highly Scattering Media: a Round-Trip Optical Transmission Matrix Method
作者: Zhuang, B (Zhuang, Bin); Xu, CF (Xu, Chengfang); Geng, Y (Geng, Yi); Zhao, GZ (Zhao, Guangzhi); Chen, H (Chen, Hui); He, ZQ (He, Zhengquan); Ren, LY (Ren, Liyong)
来源出版物: APPLIED SCIENCES-BASEL 卷: 8 期: 7 文献号: 1036 DOI: 10.3390/app8071036 出版年: JUL 2018
摘要: Imaging an object hidden behind a highly scattering medium is difficult since the wave has gone through a round-trip distortion: On the way in for the illumination and on the way out for the detection. Although various approaches have recently been proposed to overcome this seemingly intractable problem, they are limited to two-dimensional (2D) intensity imaging because the phase information of the object is lost. In such a case, the morphological features of the object cannot be recovered. Here, based on the round-trip optical transmission matrix of the scattering medium, we propose an imaging method to recover the complex amplitude (both the amplitude and the phase) information of the object. In this way, it is possible to achieve the three-dimensional (3D) complex amplitude imaging. To preliminarily verify the effectiveness of our method, a simple virtual complex amplitude object has been tested. The experiment results show that not only the amplitude but also the phase information of the object can be recovered directly from the distorted output optical field. Our method is effective to the thick scattering medium and does not involve scanning during the imaging process. We believe it probably has potential applications in some new fields, for example, using the scattering medium itself as an imaging sensor, instead of a barrier.
入藏号: WOS:000441814300026
ISSN: 2076-3417
________________________________________
第 134 条,共 322 条
标题: The Motion Planets Detection and Tracking Algorithm Based on Gestalt Principle
作者: Qiu, S (Qiu Shi); Tang, Y (Tang Ying); Zhang, WB (Zhang Wenbo); Feng, J (Feng Jun); Zhang, FC (Zhang Fuchun); Li, C (Li Chen)
来源出版物: CHINESE JOURNAL OF ELECTRONICS 卷: 27 期: 4 页: 808-812 DOI: 10.1049/cje.2017.11.006 出版年: JUL 2018
摘要: The moving planets have a few of pixels which can lead to lacking enough image characteristics when tracking them. So we propose the motion planets detection and tracking algorithm based on gestalt principle. We structure Gaussian mixture model to detect the motion area from the visual cognition perspective, and use astronomy images graphics characteristics to confirm the planet position. Then we propose space-time fusion model for tracking planet. All the experiments use 1000 16-bit-frame images of wide view CCD camera which contain 5684 motion planets in total. The results show that our algorithm reaches an accuracy of 94% and has robustness.
入藏号: WOS:000439399000019
ISSN: 1022-4653
eISSN: 2075-5597
________________________________________
第 135 条,共 322 条
标题: Cascaded Subpatch Networks for Effective CNNs
作者: Jiang, XH (Jiang, Xiaoheng); Pang, YW (Pang, Yanwei); Sun, ML (Sun, Manli); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 7 页: 2684-2694 DOI: 10.1109/TNNLS.2017.2689098 出版年: JUL 2018
摘要: Conventional convolutional neural networks use either a linear or a nonlinear filter to extract features from an image patch (region) of spatial size H x W (typically, H is small and is equal to W, e.g., H is 5 or 7). Generally, the size of the filter is equal to the size H x W of the input patch. We argue that the representational ability of equal-size strategy is not strong enough. To overcome the drawback, we propose to use subpatch filter whose spatial size h x w is smaller than H x W. The proposed subpatch filter consists of two subsequent filters. The first one is a linear filter of spatial size h x w and is aimed at extracting features from spatial domain. The second one is of spatial size 1 x 1 and is used for strengthening the connection between different input feature channels and for reducing the number of parameters. The subpatch filter convolves with the input patch and the resulting network is called a subpatch network. Taking the output of one subpatch network as input, we further repeat constructing subpatch networks until the output contains only one neuron in spatial domain. These subpatch networks form a new network called the cascaded subpatch network (CSNet). The feature layer generated by CSNet is called the csconv layer. For the whole input image, we construct a deep neural network by stacking a sequence of csconv layers. Experimental results on five benchmark data sets demonstrate the effectiveness and compactness of the proposed CSNet. For example, our CSNet reaches a test error of 5.68% on the CIFAR10 data set without model averaging. To the best of our knowledge, this is the best result ever obtained on the CIFAR10 data set.
入藏号: WOS:000436420400002
PubMed ID: 28504949
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 136 条,共 322 条
标题: Patch Alignment Manifold Matting
作者: Li, XL (Li, Xuelong); Liu, K (Liu, Kang); Dong, YS (Dong, Yongsheng); Tao, DC (Tao, Dacheng)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 7 页: 3214-3226 DOI: 10.1109/TNNLS.2017.2727140 出版年: JUL 2018
摘要: Image matting is generally modeled as a space transform from the color space to the alpha space. By estimating the alpha factor of the model, the foreground of an image can be extracted. However, there is some dimensional information redundancy in the alpha space. It usually leads to the misjudgments of some pixels near the boundary between the foreground and the background. In this paper, a manifold matting framework named Patch Alignment Manifold Matting is proposed for image matting. In particular, we first propose a part modeling of color space in the local image patch. We then perform whole alignment optimization for approximating the alpha results using subspace reconstructing error. Furthermore, we utilize Nesterov's algorithm to solve the optimization problem. Finally, we apply some manifold learning methods in the framework, and obtain several image matting methods, such as named ISOMAP matting and its derived Cascade ISOMAP matting. The experimental results reveal that the manifold matting framework and its two examples are effective when compared with several representative matting methods.
入藏号: WOS:000436420400044
PubMed ID: 28783643
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 137 条,共 322 条
标题: Simulation of cesium desorption behavior of porous nickel
作者: Hu, WJ (Hu, Weijie); Guo, B (Guo, Bin); Li, WL (Li, Wenlong); Wang, HF (Wang, Hongfei); Wang, HJ (Wang, Haojing)
来源出版物: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY 卷: 317 期: 1 页: 277-285 DOI: 10.1007/s10967-018-5818-0 出版年: JUL 2018
摘要: To achieve the application of artificial plasma technology in high technology, the desorption behavior of cesium metals with low ionization characteristics in porous nickel is studied in this paper. The simulated results, which are consistent with the experimental desorption results, demonstrated that the liquid-phase rate of cesium gradually decreased along the axial direction and the distribution of liquid fraction exhibited a similar trend. The results that the removal efficiency reached above 95% provide a reference for studying the controllability of release of cesium metal and the adsorption and desorption of other alkaline-earth metal experiments with porous nickel.
入藏号: WOS:000435823100029
ISSN: 0236-5731
eISSN: 1588-2780
________________________________________
第 138 条,共 322 条
标题: Generation of dark solitons in Er-doped fiber laser based on ferroferric-oxide nanoparticles
作者: Li, L (Li, Lu); Wang, YG (Wang, Yonggang); Wang, X (Wang, Xi); Lv, RD (Lv, Ruidong); Liu, SC (Liu, Sicong); Chen, ZD (Chen, Zhendong); Wang, J (Wang, Jiang)
来源出版物: OPTICS AND LASER TECHNOLOGY 卷: 103 页: 354-358 DOI: 10.1016/j.optlastec.2018.01.060 出版年: JUL 2018
摘要: The study presents the dark solitons generation in Er-doped mode-locked fiber laser based on ferroferric-oxide (Fe3O4) nanoparticles. The D-shaped fiber deposited with Fe3O4 nanoparticles is used as the bire-fringence and nonlinearity device. The dark solitons with repetition rate of 13.5 MHz are obtained in the pump power of 350 mW. The bright-dark soliton pairs are also observed by properly adjusting the polarization state at the pump power of 400 mW. The results in this paper demonstrate that Fe3O4 nanoparticles are the promising materials for generating dark solitons in fiber lasers. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000427339000046
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Lu                  0000-0002-3097-1954

ISSN: 0030-3992
eISSN: 1879-2545
________________________________________
第 139 条,共 322 条
标题: Unsupervised image saliency detection with Gestalt-laws guided optimization and visual attention based refinement
作者: Yan, YJ (Yan, Yijun); Ren, JC (Ren, Jinchang); Sun, GY (Sun, Genyun); Zhao, HM (Zhao, Huimin); Han, JW (Han, Junwei); Li, XL (Li, Xuelong); Marshall, S (Marshall, Stephen); Zhan, J (Zhan, Jin)
来源出版物: PATTERN RECOGNITION 卷: 79 页: 65-78 DOI: 10.1016/j.patcog.2018.02.004 出版年: JUL 2018
摘要: Visual attention is a kind of fundamental cognitive capability that allows human beings to focus on the region of interests (ROls) under complex natural environments. What kind of ROls that we pay attention to mainly depends on two distinct types of attentional mechanisms. The bottom-up mechanism can guide our detection of the salient objects and regions by externally driven factors, i.e. color and location, whilst the top-down mechanism controls our biasing attention based on prior knowledge and cognitive strategies being provided by visual cortex. However, how to practically use and fuse both attentional mechanisms for salient object detection has not been sufficiently explored. To the end, we propose in this paper an integrated framework consisting of bottom-up and top-down attention mechanisms that enable attention to be computed at the level of salient objects and/or regions. Within our framework, the model of a bottom-up mechanism is guided by the gestalt-laws of perception. We interpreted gestalt-laws of homogeneity, similarity, proximity and figure and ground in link with color, spatial contrast at the level of regions and objects to produce feature contrast map. The model of top-down mechanism aims to use a formal computational model to describe the background connectivity of the attention and produce the priority map. Integrating both mechanisms and applying to salient object detection, our results have demonstrated that the proposed method consistently outperforms a number of existing unsupervised approaches on five challenging and complicated datasets in terms of higher precision and recall rates, AP (average precision) and AUC (area under curve) values. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000430903000006
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Ren, Jinchang                  0000-0001-6116-3194
Yan, Yijun                  0000-0003-0224-0078
Li, Xuelong                  0000-0002-0019-4197
Marshall, Stephen                  0000-0001-7079-5628

ISSN: 0031-3203
eISSN: 1873-5142
________________________________________
第 140 条,共 322 条
标题: Secure and privacy-preserving data sharing in the cloud based on lossless image coding
作者: Khelifi, F (Khelifi, Fouad); Brahimi, T (Brahimi, Tahar); Han, JG (Han, Jungong); Li, XL (Li, Xuelong)
来源出版物: SIGNAL PROCESSING 卷: 148 页: 91-101 DOI: 10.1016/j.sigpro.2018.02.016 出版年: JUL 2018
摘要: Image and video processing in the encrypted domain has recently emerged as a promising research area to tackle privacy-related data processing issues. In particular, reversible data hiding in the encrypted domain has been suggested as a solution to store and manage digital images securely in the cloud while preserving their confidentiality. However, although efficiency has been claimed with reversible data hiding techniques in encrypted images (RDHEI), reported results show that the cloud service provider cannot add more than 1 bit per pixel (bpp) of additional data to manage stored images. This paper highlights the weakness of RDHEI as a suggested approach for secure and privacy-preserving cloud computing. In particular, we propose a new, simple, and efficient approach that offers the same level of data security and confidentiality in the cloud without the process of reversible data hiding. The proposed idea is to compress the image via a lossless image coder in order to create space before encryption. This space is then filled with a randomly generated sequence and combined with an encrypted version of the compressed bit stream to form a full resolution encrypted image in the pixel domain. The cloud service provider uses the created room in the encrypted image to add additional data and produces an encrypted image containing additional data in a similar fashion. Assessed with the lossless Embedded Block Coding with Optimized Truncation (EBCOT) algorithm on natural images, the proposed scheme has been shown to exceed the capacity of 3 bpp of additional data while maintaining data security and confidentiality. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000428824600010
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197
Han, Jungong                  0000-0003-4361-956X

ISSN: 0165-1684
eISSN: 1872-7557
________________________________________
第 141 条,共 322 条
标题: Hypergraph dominant set based multi-video summarization
作者: Ji, Z (Ji, Zhong); Zhang, YY (Zhang, Yuanyuan); Pang, YW (Pang, Yanwei); Li, XL (Li, Xuelong)
来源出版物: SIGNAL PROCESSING 卷: 148 页: 114-123 DOI: 10.1016/j.sigpro.2018.01.028 出版年: JUL 2018
摘要: Multi-Video Summarization (MVS) aims at condensing a large number of web videos by the same search query into a compact storyboard or video skimming. Although video summarization has achieved great progress, most existing work focuses only on extracting a summary from a single video. The genre specific assumptions for Single Video Summarization (SVS) often do not hold for MVS. Moreover, the complex data characteristics among web videos make MVS more challenging. To well address the challenges in MVS, this paper presents a novel framework with Hypergraph Dominant Set (HDS), termed MVS-HDS. Specifically, we first formulate the MVS task into a problem of finding dominant sets in a hypergraph. Then, with the help of web images searched by the same query, a Query Dependent Maximum Marginal Relevance (QD-MMR) method is developed to refine these keyframe candidates by balancing the criteria of conciseness and query adaptation. Finally, to make the summary easy to understand, we further present a Graph-based Topical Closeness (GTC) method to make it more comprehensible. Extensive experiments show that the proposed framework clearly outperforms the state-of-the-art methods. (C) 2018 Published by Elsevier B.V.
入藏号: WOS:000428824600012
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0165-1684
eISSN: 1872-7557
________________________________________
第 142 条,共 322 条
标题: Method to measure the temporal resolution of x-ray framing camera
作者: Yuan, Z (Yuan, Zheng); Chen, T (Chen, Tao); Yang, ZW (Yang, Zhiwen); Li, J (Li, Jin); Cao, ZR (Cao, Zhurong); Wu, BJ (Wu, Bingjing); Qi, WB (Qi, Wenbo); Wang, F (Wang, Feng); Yang, JM (Yang, Jiamin)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 7 文献号: 074101 DOI: 10.1117/1.OE.57.7.074101 出版年: JUL 2018
摘要: X-ray framing camera (XFC) is usually used as the principal diagnostic tool in inertial confinement fusion research. The methods on how to precisely calibrate the temporal resolution are important topics for XFC with several picoseconds gate time. A method to measure the temporal resolution of XFCs is proposed based on a high-power subpicosecond ultraviolet laser facility called LLG-ultimate. In our method, series of duraluminium alloy stepped reflective surfaces are used to separate the incident laser beam into sequentially delayed beams with equal size, spacing, and time interval. The temporal resolution of XFC can be measured if the sequentially delayed beams irradiate a gold photocathode microstrip line while the high-voltage pulse transferring along the same area simultaneously. A Fabry-Perot etalon is placed in the light path, improving the probability of synchronization of the voltage pulse and laser pulse. The accuracy of this measurement method can be very high by reducing the time interval of the sequentially delayed beams. (C) 2018 society of Photo-Opticai Instrumentation Engineers (SPIE).
入藏号: WOS:000441067200013
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 143 条,共 322 条
标题: Temperature analysis of Cassegrain optical antenna for space laser communication
作者: Zhao, YY (Zhao, Yiyi); Ma, XL (Ma, Xiaolong); Xue, B (Xue, Bin); Li, F (Li, Fu); He, YH (He, Yinghong); Lv, J (Lv, Juan); Yan, XT (Yan, Xingtao); Yu, JR (Yu, Jirui); Xiang, M (Xiang, Meng)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 7 文献号: 076103 DOI: 10.1117/1.OE.57.7.076103 出版年: JUL 2018
摘要: The thermal stability of optical antennas is a key parameter determining the performance of satellite optical communication links. The effects of uniform temperature changes on the performance of a Cassegrain optical antenna are discussed. In addition, a simple theoretical model is proposed to describe the defocusing distance and wavefront aberration (power) as a function of temperature. Through the theoretical model, the thermal stability can be quickly assessed in the optical design stage. The alignment data and thermal experimental results are consistent with the theoretical model. (C) The Authors Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication.
入藏号: WOS:000441067200029
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 144 条,共 322 条
标题: Suppression of the critical collapse for one-dimensional solitons by saturable quintic nonlinear lattices
作者: Shi, JC (Shi, Jincheng); Zeng, JH (Zeng, Jianhua); Malomed, BA (Malomed, Boris A.)
来源出版物: CHAOS 卷: 28 期: 7 文献号: 075501 DOI: 10.1063/1.5015933 出版年: JUL 2018
摘要: The stabilization of one-dimensional solitons by a nonlinear lattice against the critical collapse in the focusing quintic medium is a challenging issue. We demonstrate that this purpose can be achieved by combining a nonlinear lattice and saturation of the quintic nonlinearity. The system supports three species of solitons, namely, fundamental (even-parity) ones and dipole (odd-parity) modes of onand off-site-centered types. Very narrow fundamental solitons are found in an approximate analytical form, and systematic results for very broad unstable and moderately broad partly stable solitons, including their existence and stability areas, are produced by means of numerical methods. Stability regions of the solitons are identified by means of systematic simulations. The stability of all the soliton species obeys the Vakhitov-Kolokolov criterion. Published by AIP Publishing.
入藏号: WOS:000440606100031
PubMed ID: 30070511
会议名称: 19th MEDYFINOL Conference
会议日期: DEC 05-09, 2016
会议地点: Valdivia, CHILE
会议赞助商: MEDYFINOL
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
ceng, jian hua                  0000-0003-0189-1856

ISSN: 1054-1500
eISSN: 1089-7682
________________________________________
第 145 条,共 322 条
标题: Diurnal Dynamics and Seasonal Variations of Total Suspended Particulate Matter in Highly Turbid Hangzhou Bay Waters Based on the Geostationary Ocean Color Imager
作者: Liu, J (Liu, Jia); Liu, JH (Liu, Jiahang); He, XQ (He, Xianqiang); Pan, DL (Pan, Delu); Bai, Y (Bai, Yan); Zhu, F (Zhu, Feng); Chen, TQ (Chen, Tieqiao); Wang, YH (Wang, Yihao)
来源出版物: IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING 卷: 11 期: 7 页: 2170-2180 DOI: 10.1109/JSTARS.2018.2830335 出版年: JUL 2018
摘要: Characterized by high concentrations and significant diurnal dynamics, total suspended particulate matter (TSM) in Hangzhou Bay (HZB) can influence the water quality. Both cruise sampling and polar-orbiting satellite remote sensing make it difficult to synoptically delineate such matter in coastal regions due to insufficient spatiotemporal resolution. However, near-real-time monitoring from the Geostationary Ocean Color Imager (GOCI), the world's first geostationary satellite ocean color sensor, now allows hourly observations of target areas. Here, we developed an empirical TSM retrieval algorithm for the GOCI, based on the spectral absorption index (SAI). Additionally, validations of the atmospheric correction algorithm and SAI TSM algorithm were conducted, with the GOCI-retrieved normalized water-leaving radiance (Lwn) and TSM well-matched with in situ values. Moreover, the diurnal dynamics corresponded to tidal phases, with a maximum-of 5000 mg/L in central HZB. The seasonal variations in TSM were also determined by freshwater inputs and sediment loads, with correlation coefficients of -0.77 and 0.84, respectively. The increased wind speed in winter enhanced vertical mixing and favored the resuspension of sediment to the upper layer, and therefore TSM was higher in winter than in summer. These results highlight the feasibility of using geostationary ocean color remote sensing to monitor short-term and regional oceanic phenomena in coastal waters. Furthermore, this study contributes to our understanding of related sediment dynamics and physical biogeochemical processes.
入藏号: WOS:000440035600003
ISSN: 1939-1404
eISSN: 2151-1535
________________________________________
第 146 条,共 322 条
标题: Improvement of the Faraday effect in Ge-S based chalcogenide glasses via gallium and lead compositional modifications
作者: Xu, YT (Xu, Yantao); Xiao, XS (Xiao, Xusheng); Cui, XX (Cui, Xiaoxia); Gao, F (Gao, Fei); Cui, J (Cui, Jian); Liu, XG (Liu, Xiaogang); Guo, H (Guo, Haitao); She, JB (She, Jiangbo); Chen, G (Chen, Gang); Lu, M (Lu, Min); Peng, B (Peng, Bo)
来源出版物: OPTICAL MATERIALS EXPRESS 卷: 8 期: 7 页: 1754-1761 DOI: 10.1364/OME.8.001754 出版年: JUL 1 2018
摘要: The diamagnetic performance of GeS2-Ga2S3 and GeS2-Ga2S3-PbI2 chalcogenide glasses were investigated, and the composition, wavelength and temperature dependences of the Verdet constant were discussed in detail. It indicates that the contributions to the Verdet constant for each kind of ion are in the order of V-Pb>V-Ga>V-Ge in these chalcogenide glasses, and the Becquerel rule is proved to be an effective guidance for predicting the Verdet constant value. A large Verdet constant is obtained in 68GeS(2)center dot 17Ga(2)S(3)center dot 15PbI(2) composition glass and the value is 0.230 min.G(-1).cm(-1) at 635nm, which is greatly larger than those of commercial diamagnetic glasses. Besides, the temperature coefficient of Verdet constant can be regarded as a constant between 278 and 368 K, indicating these chalcogenide glasses are good candidates for magneto-optical devices in temperature instability conditions. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000437453500006
ISSN: 2159-3930
________________________________________
第 147 条,共 322 条
标题: Highly efficient and tunable white light emission of Sn2+-Dy3+ co-doped fluorophosphate glasses
作者: Zheng, JJ (Zheng, Jiajin); Lu, Q (Lu, Qiang); Zheng, RL (Zheng, Ruilin); Zou, H (Zou, Hui); Yu, KH (Yu, Kehan); Wei, W (Wei, Wei)
来源出版物: OPTICAL MATERIALS EXPRESS 卷: 8 期: 7 页: 1780-1787 DOI: 10.1364/OME.8.001780 出版年: JUL 1 2018
摘要: A series of Sn2+-Dy3+ co-doped fluorophosphate glasses (FPGs) were prepared by the melt quenching method. The luminescent properties and energy transfer mechanisms of the FPGs glasses were investigated through photoluminescence and decay lifetime analysis. By controlling the concentration of Dy3+, the FPGs present a white light with a CIE chromaticity coordinate of (0.311, 0.330), which is very close to the standard equal energy white light illumination. The corresponding quantum efficiency, CRI and the brightness are 56.3%, 75 and 6706 cd/m(2), respectively. Furthermore, the physical and chemical stability and thermal properties were also analyzed using differential scanning calorimetry and a thermal conductivity detector. The corresponding values of the Delta T (T-x-T-g) and thermal conductivity are 155 degrees C and 3.02 similar to 3.31 W/m.K, respectively. These results demonstrate that the FPGs can be a promising candidate for tunable white light phosphors. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000437453500009
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Kehan         K-7635-2019         

ISSN: 2159-3930
________________________________________
第 148 条,共 322 条
标题: Nonlinear Compression of Ultrashort-Pulse Laser to 36 fs With 556-MW Peak Power
作者: Li, F (Li, Feng); Yang, Z (Yang, Zhi); Wang, YS (Wang, Yishan); Lv, ZG (Lv, Zhiguo); Wei, YF (Wei, Yufeng); Wang, XL (Wang, Xianglin); Hu, XH (Hu, Xiaohong); Yang, HN (Yang, Hening); Li, QL (Li, Qianglon); Yang, XJ (Yang, Xiaojun); Zhao, W (Zhao, Wei)
来源出版物: IEEE PHOTONICS TECHNOLOGY LETTERS 卷: 30 期: 13 页: 1198-1201 DOI: 10.1109/LPT.2018.2839592 出版年: JUL 1 2018
摘要: The setup of nonlinear pulse compression with hollow-core photonic crystal fiber (HC-PCF) is demonstrated. In our experiment, the HC-PCF is just put in the air with no extra gas fill. The spectrum is effectively broadened to more than 60 nm by delivering the ultrashort laser in the HC-PCF and compressing the pulse with Gires-Tournois interferometer-type dispersion mirrors. The initial pulse duration of 279 fs has been shortened to 36 fs with 20 mu J of pulse energy, which corresponds to a peak power of about 556 MW. To our best knowledge, it is the highest peak power obtained from the solid-state laser at the wavelength around 1 mu m by using Kagome-type HC-PCF without extra gas fill. With precise dispersion compensation and higher input pulse energy, even shorter pulse width and higher peak power can he obtained.
入藏号: WOS:000435349900009
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Feng, Li                  0000-0003-0846-7273
Wang, Xianglin                  0000-0003-3831-9570

ISSN: 1041-1135
eISSN: 1941-0174
________________________________________
第 149 条,共 322 条
标题: Near infrared step-zoom doublet lens based on dielectric metasurfaces
作者: Li, FF (Li, Feifei); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu)
来源出版物: JOURNAL OF OPTICS 卷: 20 期: 7 文献号: 075105 DOI: 10.1088/2040-8986/aaca4f 出版年: JUL 2018
摘要: Optical metasurfaces are ultrathin planar nanostructures that manipulate wavefronts and polarization of light. Here, we propose a step-zoom doublet lens of dual focal lengths composed of two dielectric metasurfaces at 1550 nm wavelength. The highly integrated doublet lens can operate with long and short focal length modes by easily converting the handedness of the incident circular polarized light, meanwhile the focal plane remains unchanged. Two tight focal spots 0.57 lambda and 0.79 lambda are achieved with corresponding numerical aperture of 0.95 and 0.66, respectively. Compared with a conventional zoom system, this step-zoom doublet lens is ultrathin, compact and flexibility. The ultra-compact doublet lens can be applied in zoom imaging, infrared detection and on-chip photonics components.
入藏号: WOS:000435728400001
ISSN: 2040-8978
eISSN: 2040-8986
________________________________________
第 150 条,共 322 条
标题: Effects of Air/H2O Discharge Plasma on Propane Combustion Enhancement Using Dielectric Barrier Discharges
作者: Li, YP (Li, Yanping); Niu, GH (Niu, Guanghui); Wang, X (Wang, Xu); Tang, J (Tang, Jie); Duan, YX (Duan, Yixiang)
来源出版物: PLASMA CHEMISTRY AND PLASMA PROCESSING 卷: 38 期: 4 特刊: SI 页: 831-850 DOI: 10.1007/s11090-018-9896-0 出版年: JUL 2018
摘要: Combustion provides about 80% energy for our daily life and industrial production. But thermal efficiency of traditional combustion technologies is low, which causes energy waste and serious environmental pollution. In order to improve the combustion efficiency, a combined method based on non-equilibrium plasma generated by dielectric barrier discharge and OH radicals coming from water-steam additive was proposed in this work, and plasma assisted propane combustion was examined and evaluated. The results indicated that when relative humidity (RH) was 20% and applied peak voltage was fixed at 8.75 kV, the relative intensity of OH radical and the flame temperature reached the maximum value at the flame root. At the same time, propane combustion was the most complete. In addition, we found that the erosion of the inner electrode was weakened by H2O addition, and the symmetry of discharge current was changed from symmetry to asymmetry with the increase of RH. Compared with the pure air undischarged combustion, when the relative humidity was 20% and under the discharge conditions of 8.75 kV, the lean-burn extinction limit was extended to 0.4,which is far lower than the traditional lean-burn limit (0.51).
入藏号: WOS:000433079900013
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Niu, Guanghui                  0000-0003-4522-7826

ISSN: 0272-4324
eISSN: 1572-8986

第 151 条,共 322 条
标题: Multiple plasmonic resonance excitations on graphene metamaterials for ultrasensitive terahertz sensing
作者: Chen, X (Chen, Xu); Fan, WH (Fan, Wenhui); Song, C (Song, Chao)
来源出版物: CARBON 卷: 133 页: 416-422 DOI: 10.1016/j.carbon.2018.03.051 出版年: JUL 2018
摘要: A three-dimensional graphene metamaterial structure consisting of dielectric pillar arrays covered by graphene monolayer with metal layer underneath is proposed and investigated, which can realize the efficient excitations of multiple plasmonic resonance modes under incident terahertz (THz) wave. The multiple plasmonic resonance modes are highly sensitive to the change of analyte refractive index and thickness, and the frequency sensitivity of each resonance mode can reach up to 1.402, 1.687 and 1.643 THz per refractive index unit, respectively. By controlling the Fermi level of graphene, the resonance frequency can be tuned dynamically. Moreover, the proposed structure has three absorption peaks with absorptivity more than 95%, it is polarization-insensitive and can perform very well in a wide incident angles for transverse electric and transverse magnetic waves. This proposed structure can be utilized for active THz plasmonic devices such as multiple channel sensors and absorbers. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000431010600052
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Fan, Wen-Hui         M-1060-2018         0000-0003-2554-6723

ISSN: 0008-6223
eISSN: 1873-3891
________________________________________
第 152 条,共 322 条
标题: RF Photonics: An Optical Microcombs' Perspective
作者: Wu, JY (Wu, Jiayang); Xu, XY (Xu, Xingyuan); Nguyen, TG (Nguyen, Thach G.); Chu, ST (Chu, Sai Tak); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)
来源出版物: IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS 卷: 24 期: 4 文献号: 6101020 DOI: 10.1109/JSTQE.2018.2805814 出版年: JUL-AUG 2018
摘要: Over the past decade, optical frequency combs generated by high-Q microresonators, or optical microcombs, which feature compact device footprints, low power consumption, and high repetition rates in broad optical bandwidths, have led to a revolution in a wide range of fields including metrology, telecommunications, radio frequency (RF) photonics, spectroscopy, sensing, and quantum optics. Among these, an application that has attracted great interest is the use of optical microcombs for RF photonics, where they offer enhanced functionalities as well as reduced size and power consumption over other approaches. This paper reviews the recent advances in this emerging field. We provide an overview of the main achievements that have been obtained to date, and highlight the strong potential of optical microcombs for RF photonics applications. We also discuss some of the open challenges and limitations that need to be addressed for practical applications.
入藏号: WOS:000428529800001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X
Xu, Xingyuan                  0000-0002-8190-4700
Nguyen, Thach                  0000-0002-8409-5638
Mitchell, Arnan         C-5017-2008         0000-0002-2463-2956

ISSN: 1077-260X
eISSN: 1558-4542
________________________________________
第 153 条,共 322 条
标题: Eye centre localisation with hybrid regression framework
作者: Li, B (Li, Bin)
来源出版物: ELECTRONICS LETTERS 卷: 54 期: 13 页: 819-+ DOI: 10.1049/el.2018.0123 出版年: JUN 28 2018
摘要: The location of the eye is an important feature for computer vision and pattern recognition applications including psychological analysis, facial expression recognition and auxiliary driving. Most of the current work typically performs face detection first, followed by eye centre localisation. Such an algorithm fails to locate eye centre in some cases because the illuminance and external environment changes the facial features blurred in the images; therefore, the traditional face detectors cannot accurately determine the region of the face. A method for eye centre localisation which is based on convolution neural networks and regression framework is proposed. First, eye region is selected from the facial images according to convolutional neural networks. Then, the accurate eye centre is estimated by a linear regression model. Finally, the method on Itioli) and GI4E. datasets is evaluated. The experimental result showed that the proposed algorithm has comparable or better performance compared with the state-of-the-art methods.
入藏号: WOS:000435463600014
ISSN: 0013-5194
eISSN: 1350-911X
________________________________________
第 154 条,共 322 条
标题: Arbitrary multiple beam forming by two cascaded liquid crystal optical phased arrays
作者: Wu, L (Wu, Liang); Wang, XR (Wang, Xiangru); He, XX (He, Xiaoxian); Huang, ZQ (Huang, Ziqiang); Huang, XN (Huang, XinNing); Xiong, CD (Xiong, Caidong)
来源出版物: OPTICS EXPRESS 卷: 26 期: 13 页: 17066-17077 DOI: 10.1364/OE.26.017066 出版年: JUN 25 2018
摘要: A new method for non-mechanical laser beam splitting and steering is demonstrated. Two cascaded liquid crystal optical phased arrays (LC-OPAs) controllably modulate the amplitude and phase of an incident laser beam to realize the near-field wavefronts of multiple simultaneous beams with arbitrary directions. Diffraction between the two arrays is avoided by precise 4-f imaging from one LC-OPA to the other (array resolution 1x1920). In the method of cascaded amplitude and phase (CAP) devices, numerical simulation results show the characteristics of amplitude and phase modulation profiles, as well as the far-field intensity patterns. Both the numerical and experimental results clearly demonstrate the capabilities of fast multi-beam forming with high efficiency (>85%, 4 beams) and accuracy (deviation <90 mu rad). (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000436226800084
PubMed ID: 30119524
ISSN: 1094-4087
________________________________________
第 155 条,共 322 条
标题: Influences of high-order dispersion on temporal and spectral properties of microcavity solitons
作者: Liu, ML (Liu, Mulong); Wang, L (Wang, Leiran); Sun, QB (Sun, Qibing); Li, SQ (Li, Siqi); Ge, ZQ (Ge, Zhiqiang); Lu, ZZ (Lu, Zhizhou); Zeng, C (Zeng, Chao); Wang, GX (Wang, Guoxi); Zhang, WF (Zhang, Wenfu); Hu, XH (Hu, Xiaohong); Zhao, W (Zhao, Wei)
来源出版物: OPTICS EXPRESS 卷: 26 期: 13 页: 16477-16487 DOI: 10.1364/OE.26.016477 出版年: JUN 25 2018
摘要: We theoretically and numerically investigate the effects of high-order dispersion (HOD) on microcavity solitons, both in time and frequency domain with an extended normalized Lugiato-Lefever equation (LLE). The observed temporal drift of bright and dark solitons is shown to originate from high-odd-order dispersion, while the sign determines the direction of soliton movement and the amplitude decides the drift speed. HOD can also be introduced to stabilize the breathing bright and dark cavity solitons. In spectral domain, the nonlinear symmetry breaking is mainly introduced by third-order dispersion, whereas both third- and fourth-order dispersion can introduce dispersive wave accompanied by soliton tail oscillation. This work could give insight for exploring detailed intracavity pulse dynamics and spectral characteristics of Kerr combs influenced by HOD, as well as provide a viable route to delicate control of Kerr comb generation through tailoring the dispersion parameters. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000436226800038
PubMed ID: 30119478
ISSN: 1094-4087
________________________________________
第 156 条,共 322 条
标题: Simulation and application of the emission line O19P18 of O-2 (a(1)Delta(g) ) dayglow near 1.27 mu m for wind observations from limb-viewing satellites
作者: Wu, KJ (Wu, Kuijun); Fu, D (Fu, Di); Feng, YT (Feng, Yutao); Li, J (Li, Juan); Hao, XB (Hao, Xiongbo); Li, FQ (Li, Faquan)
来源出版物: OPTICS EXPRESS 卷: 26 期: 13 页: 16984-16999 DOI: 10.1364/OE.26.016984 出版年: JUN 25 2018
摘要: The O-2 (a(1)Delta(g)) emission near 1.27 gm has relatively bright signal and extended altitude coverage and provides an important means to remotely sense the compositional structures and dynamical features of the upper atmosphere globally. In this paper, we report the simulation and application of O-2 (a(1)Delta(g)) dayglow near 1.27 mu m for wind observations from limb-viewing satellites. A line by line radiative transfer model of the O-2 (a(1)Delta(g), v' = 0) -> O-2 (X-3 Sigma(g), v '' = 0) band is developed by taking both multiple scattering radiative transfer and nonlocal thermal equilibrium (non-LTE) models into account. The emission line O19P18 (7772.030 cm(-1)) with weak self-absorption, bright radiation intensity, and large spectral separation range is proved to be suitable for limb-viewing wind detection, due to its advantages of significantly lower cost, risk, and platform requirements. In order to ascertain the wind precision of O19P18, observations by a DASH-type (the Doppler asymmetric spatial heterodyne) instrument are simulated. The simulated results indicate a wind measurement precision of 1-2 m/s over an altitude range of 40 to 70 km in general, and possibly to 2-4 m/s due to a strong dependence on the spectral interference of the scattered sunlight background. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000436226800075
PubMed ID: 30119515
ISSN: 1094-4087
________________________________________
第 157 条,共 322 条
标题: Optical design of a distributed zoom concentric multiscale meteorological instrument
作者: Shen, Y (Shen, Yang); Wang, H (Wang, Hu); Wang, CC (Wang, Chenchen); Yue, P (Yue, Pan); Xue, YK (Xue, Yaoke); Bai, Z (Bai, Zhe); Fan, XW (Fan, Xuewu)
来源出版物: APPLIED OPTICS 卷: 57 期: 18 页: 5168-5179 DOI: 10.1364/AO.57.005168 出版年: JUN 20 2018
摘要: A meteorological moderate resolution sensor requires large field of view (FOV) and low distortion imaging. At present, a fixed-focus camera combined with a whiskbroom scanning mechanism or a fixed-focus multi-camera combined with pushbroom scanning mechanism is being used. Owing to the fixed focal length of the camera, a large FOV causes the difference of imaging distance and ground imaging angle between the nadir point and the edge of the FOV to be significantly large, resulting in a large difference in the resolution between the nadir point and the edge of the FOV. The study proposes to simultaneously adopt a distributed zoom concentric multiscale system to realize a large FOV, low distortion, and high quality imaging to coordinate with different compensation lenses to achieve a different FOV corresponding to different focal lengths, where the resolution drop between the nadir point and the edge of the FOV is reduced. To ensure the same illumination of the entire FOV, the entire system possesses the same F# with different FOVs exhibiting different entrance pupil diameters. The study analyzes the principle of aberration compensation of a concentric multiscale system when both the FOV and entrance pupil diameter are changed and completes three groups of optical design of different focal lengths with uniform F#. The results indicate that the system has advantages of low distortion and high imaging quality in the entire FOV. Moreover, the resolution drop in the entire FOV is reduced to approximately 50% of the traditional design scheme. To verify the implementability of the system, a set of prototype manufacturing and imaging experiments are conducted to prove that the system has satisfactory implementability, and the imaging quality is also satisfactory. (C) 2018 Optical Society of America
入藏号: WOS:000435841800053
PubMed ID: 30117981
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 158 条,共 322 条
标题: Terahertz and infrared characteristic absorption spectra of aqueous glucose and fructose solutions
作者: Song, C (Song, Chao); Fan, WH (Fan, Wen-Hui); Ding, L (Ding, Ling); Chen, X (Chen, Xu); Chen, ZY (Chen, Ze-You); Wang, K (Wang, Kai)
来源出版物: SCIENTIFIC REPORTS 卷: 8 文献号: 8964 DOI: 10.1038/s41598-018-27310-7 出版年: JUN 12 2018
摘要: In this paper, the terahertz (THz) and infrared (IR) characteristic absorption spectra of aqueous glucose solutions and aqueous fructose solutions with different concentrations were measured and studied. The absorption spectra of these two molecules in solid-state and in aqueous solutions were compared and analyzed, the significant effect of molecular adjacent environment on the molecular structure and vibrational mode was revealed. In addition, the THz and IR absorption spectra of these two isomers' aqueous solutions were also compared and explored. No obvious differences were found from their IR absorption features measured at room temperature, while their THz absorption spectra do have the differences, indicating THz characteristic absorption spectra more suitable for the detection and identification of aqueous glucose and fructose solutions. The results are helpful to understand the influence of aqueous solutions environment on the molecular structures and vibrational modes of the materials, and also provide a theoretical reference for the quantum chemical calculation of biological macromolecules.
入藏号: WOS:000434920800008
PubMed ID: 29895843
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Fan, Wen-Hui         M-1060-2018         0000-0003-2554-6723

ISSN: 2045-2322
________________________________________
第 159 条,共 322 条
标题: Aberration correction in holographic optical tweezers using a high-order optical vortex: publisher's note (vol 57, pg 3618, 2018)
作者: Liang, YS (Liang, Yansheng); Cai, YA (Cai, Yanan); Wang, ZJ (Wang, Zhaojun); Lei, M (Lei, Ming); Cao, ZL (Cao, Zhiliang); Wang, Y (Wang, Yue); Li, MM (Li, Manman); Yan, SH (Yan, Shaohui); Bianco, PR (Bianco, Piero R.); Yao, BL (Yao, Baoli)
来源出版物: APPLIED OPTICS 卷: 57 期: 17 页: 4857-4857 DOI: 10.1364/AO.57.004857 出版年: JUN 10 2018
入藏号: WOS:000434872300018
PubMed ID: 30118102
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 160 条,共 322 条
标题: Field effect transistor photodetector based on graphene and perovskite quantum dots
作者: Zheng, JJ (Zheng Jia-Jin); Wang, YR (Wang Ya-Ru); Yu, KH (Yu Ke-Han); Xu, XX (Xu Xiang-Xing); Sheng, XX (Sheng Xue-Xi); Hu, ET (Hu Er-Tao); Wei, W (Wei Wei)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 11 文献号: 118502 DOI: 10.7498/aps.67.20180129 出版年: JUN 5 2018
摘要: Graphene is an attractive optoelectronic material for various optoelectronic devices, especially in the field of photoelectric detection due to its high carrier mobility and fast response time. However, the relatively low light absorption cross-section and fast electron-hole recombination rate can lead to rapid exciton annihilation and small light gain, which restrict the commercial applications of pure graphene-based photodetector. The perovskite has attracted much attention because of its high photoelectric conversion efficiency in the field of solar cells. The perovskite has the advantages of long carrier diffusion distance and high optical absorption coefficient, which can effectively make up for the shortcomings of pure graphene-based field-effect transistor. In this work, a field-effect transistor photodetector is demonstrated with the combination of graphene and halide perovskite quantum dots (CsPbI3) serving as conductive channel materials. The graphene is prepared by plasma enhanced chemical vapor deposition, and the quantum dots are CsPbI3 perovskite. The electrical properties of graphene and pure graphene-based field-effect transistor are detected and analyzed by using the Raman spectrum. The results show that the graphene has good intrinsic electrical properties. Unlike previous report in which bulk perovskite was used, the perovskite quantum dot field-effect transistor photodetector has an obvious light response to 400 nm signal light, and shows the excellent photoelectrical performance. Under the illumination of 400 nm light, the signal light could be detected steadily and repeatedly by the graphene-perovskite quantum dot photodetector and converted into photocurrent. The photocurrent of the photodetector has a rapid rise, and the maximum value can reach 64 mu A at a light power of 12 mu W. The corresponding responsivity is 6.4 A.W-1, which is two orders of magnitude higher than that of the general single graphene photodetector (10(-2) A.W-1), and it is also higher than that of perovskite-based photodetector (0.4 A.W-1). In addition, the photoconductive gain and detectivity arrive at 3.7 x 10(4) and 6 x 10(7) Jones (1 Jones = 1 cm.Hz(1/2).W-1), respectively. The results of this study demonstrate that the graphene-perovskite quantum dot photodetector can be a promising candidate for commercial UV light detectors.
入藏号: WOS:000443197300029
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Kehan         K-7635-2019         

ISSN: 1000-3290
________________________________________
第 161 条,共 322 条
标题: Fast Long-Range Photon Counting Depth Imaging With Sparse Single-Photon Data
作者: Kang, Y (Kang, Yan); Li, LF (Li, Lifei); Liu, DW (Liu, Dawei); Li, DJ (Li, Dongjian); Zhang, TY (Zhang, Tongyi); Zhao, W (Zhao, Wei)
来源出版物: IEEE PHOTONICS JOURNAL 卷: 10 期: 3 文献号: 7500710 DOI: 10.1109/JPHOT.2018.2840681 出版年: JUN 2018
摘要: Fast depth imaging of noncooperative targets at a range of up to 900 m is demonstrated based on the time-of-flight time-correlated single-photon counting technique. Experimental results shown that our image system has the ability of reconstructing depth images with data of less than one photon per pixel. Especially, utilizing a modified total variation regularization algorithm with an optimal initial value, the acquisition time necessary for each pixel could be reduced by a factor of 8 compared to the traditional median filter approach, and the image processing time is extremely improved. This depth imaging system is a low-light-level device for a variety of applications, such as target detection, space surveillance, and distance measurement.
入藏号: WOS:000435562000001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
zhang, tong yi                  0000-0002-7908-8046

ISSN: 1943-0655
eISSN: 1943-0647
________________________________________
第 162 条,共 322 条
标题: Key Frame Extraction in the Summary Space
作者: Li, XL (Li, Xuelong); Zhao, B (Zhao, Bin); Lu, XQ (Lu, Xiaoqiang)
来源出版物: IEEE TRANSACTIONS ON CYBERNETICS 卷: 48 期: 6 页: 1923-1934 DOI: 10.1109/TCYB.2017.2718579 出版年: JUN 2018
摘要: Key frame extraction is an efficient way to create the video summary which helps users obtain a quick comprehension of the video content. Generally, the key frames should be representative of the video content, meanwhile, diverse to reduce the redundancy. Based on the assumption that the video data are near a subspace of a high-dimensional space, a new approach, named as key frame extraction in the summary space, is proposed for key frame extraction in this paper. The proposed approach aims to find the representative frames of the video and filter out similar frames from the representative frame set. First of all, the video data are mapped to a high-dimensional space, named as summary space. Then, a new representation is learned for each frame by analyzing the intrinsic structure of the summary space. Specifically, the learned representation can reflect the representativeness of the frame, and is utilized to select representative frames. Next, the perceptual hash algorithm is employed to measure the similarity of representative frames. As a result, the key frame set is obtained after filtering out similar frames from the representative frame set. Finally, the video summary is constructed by assigning the key frames in temporal order. Additionally, the ground truth, created by filtering out similar frames from human-created summaries, is utilized to evaluate the quality of the video summary. Compared with several traditional approaches, the experimental results on 80 videos from two datasets indicate the superior performance of our approach.
入藏号: WOS:000435342400020
PubMed ID: 28693004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197
Lu, Xiaoqiang                  0000-0002-7037-5188

ISSN: 2168-2267
eISSN: 2168-2275
________________________________________
第 163 条,共 322 条
标题: A Coarse-to-Fine Semi-Supervised Change Detection for Multispectral Images
作者: Zhang, WZ (Zhang, Wuxia); Lu, XQ (Lu, Xiaoqiang); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 卷: 56 期: 6 页: 3587-3599 DOI: 10.1109/TGRS.2018.2802785 出版年: JUN 2018
摘要: Change detection is an important technique providing insights to urban planning, resources monitoring, and environmental studies. For multispectral images, most semi-supervised change detection methods focus on improving the contribution of training samples hard to be classified to the trained classifier. However, hard training samples will weaken the discrimination of the training model for multispectral change detection. Besides, these methods only use the spectral information, while the limited spectral information cannot represent objects very well. In this paper, a method named as coarse-to-fine semi-supervised change detection is proposed to solve the aforementioned problems. First, a novel multiscale feature is exploited by concatenating the spectral vector of the pixel to be detected and its adjacent pixels by different scales. Second, the enhanced metric learning is proposed to acquire more discriminant metric by strengthening the contribution of training samples easy to be classified and weakening the contribution of training samples hard to be classified to the trained model. Finally, a coarse-to-fine strategy is adopted to detect testing samples from the viewpoint of distance metric and label information of neighborhood in spatial space. The coarse detection result obtained from the enhanced metric learning is used to guide the final detection. The effectiveness of our proposed method is verified on two real-life operating scenarios, Taizhou and Kunshan data sets. Extensive experimental results demonstrate that our proposed algorithm has better performance than those of other state-of-the-art algorithms.
入藏号: WOS:000433328400047
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0196-2892
eISSN: 1558-0644
________________________________________
第 164 条,共 322 条
标题: Generation and Coherent Control of Pulsed Quantum Frequency Combs
作者: MacLellan, B (MacLellan, Benjamin); Rortocki, P (Rortocki, Piotr); Kues, M (Kues, Michael); Reimer, C (Reimer, Christian); Cortes, LR (Cortes, Luis Romero); Zhang, YB (Zhang, Yanbing); Sciara, S (Sciara, Stefania); Wetzel, B (Wetzel, Benjamin); Cino, A (Cino, Alfonso); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Moss, DJ (Moss, David J.); Caspani, L (Caspani, Lucia); Azana, J (Azana, Jose); Morandotti, R (Morandotti, Roberto)
来源出版物: JOVE-JOURNAL OF VISUALIZED EXPERIMENTS 期: 136 文献号: e57517 DOI: 10.3791/57517 出版年: JUN 2018
摘要: We present a method for the generation and coherent manipulation of pulsed quantum frequency combs. Until now, methods of preparing high-dimensional states on-chip in a practical way have remained elusive due to the increasing complexity of the quantum circuitry needed to prepare and process such states. Here, we outline how high-dimensional, frequency-bin entangled, two-photon states can be generated at a stable, high generation rate by using a nested-cavity, actively mode-locked excitation of a nonlinear micro-cavity. This technique is used to produce pulsed quantum frequency combs. Moreover, we present how the quantum states can be coherently manipulated using standard telecommunications components such as programmable filters and electro-optic modulators. In particular, we show in detail how to accomplish state characterization measurements such as density matrix reconstruction, coincidence detection, and single photon spectrum determination. The presented methods form an accessible, reconfigurable, and scalable foundation for complex high-dimensional state preparation and manipulation protocols in the frequency domain.
入藏号: WOS:000444752100063
PubMed ID: 29939165
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Wetzel, Benjamin         P-3187-2019         0000-0002-2691-0307
Caspani, Lucia         C-3777-2009         0000-0003-2711-0448

ISSN: 1940-087X
________________________________________
第 165 条,共 322 条
标题: On-orbit space camera self-calibration based on the orthogonal vanishing points obtained from solar panels
作者: Zhang, GP (Zhang, Gaopeng); Zhao, H (Zhao, Hong); Hong, Y (Hong, Yang); Ma, YY (Ma, Yueyang); Li, J (Li, Jing); Guo, HN (Guo, Huinan)
来源出版物: MEASUREMENT SCIENCE AND TECHNOLOGY 卷: 29 期: 6 文献号: 065013 DOI: 10.1088/1361-6501/aab4d6 出版年: JUN 2018
摘要: As one of the key steps of machine visual investigation, camera calibration is indispensable for obtaining an accurate 3D profile of measured objects and positioning the target. However, it is almost impossible to calibrate a camera on-orbit in real time, for the feature points in space are irregular. To self-calibrate camera parameters in orbit, we propose a method to calibrate the camera using the orthogonal vanishing points obtained from a solar panel, which is a common component of most man-made space satellites. Using two sets of images of orthogonal parallel ribs of a solar panel under any two positions, four vanishing points are achieved. Based on the geometrical property of the orthogonal vanishing point and the infinite homography relationship between the corresponding vanishing points under different camera positions, a camera self-calibration method is proposed, and constraint equations are established to calibrate the intrinsic parameters of the camera linearly. Aiming at restraining the influence of the noise on the calibration result, an objective function based on the inverse point characteristics of rectangular imaging is proposed, and the Levenberg-Marquardt optimization algorithm is used to nonlinearly optimize the intrinsic parameters. Simulated and experimental results show that the 2D reprojection error is 0.86 pixels. This method, therefore, has better applicability in some significant space and national defense missions, such as space rendezvous and docking, attack-defense, and on-orbit servicing. The optimization algorithm shows good anti-noise interference performance, therefore the robustness of the calibration algorithm is improved.
入藏号: WOS:000431455900003
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zhang, Gaopeng                  0000-0003-2452-9171

ISSN: 0957-0233
eISSN: 1361-6501
________________________________________
第 166 条,共 322 条
标题: Discriminant Analysis with Graph Learning for Hyperspectral Image Classification
作者: Chen, ML (Chen, Mulin); Wang, Q (Wang, Qi); Li, XL (Li, Xuelong)
来源出版物: REMOTE SENSING 卷: 10 期: 6 文献号: 836 DOI: 10.3390/rs10060836 出版年: JUN 2018
摘要: Linear Discriminant Analysis (LDA) is a widely-used technique for dimensionality reduction, and has been applied in many practical applications, such as hyperspectral image classification. Traditional LDA assumes that the data obeys the Gaussian distribution. However, in real-world situations, the high-dimensional data may be with various kinds of distributions, which restricts the performance of LDA. To reduce this problem, we propose the Discriminant Analysis with Graph Learning (DAGL) method in this paper. Without any assumption on the data distribution, the proposed method learns the local data relationship adaptively during the optimization. The main contributions of this research are threefold: (1) the local data manifold is captured by learning the data graph adaptively in the subspace; (2) the spatial information within the hyperspectral image is utilized with a regularization term; and (3) an efficient algorithm is designed to optimize the proposed problem with proved convergence. Experimental results on hyperspectral image datasets show that promising performance of the proposed method, and validates its superiority over the state-of-the-art.
入藏号: WOS:000436561800030
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197
Wang, Qi                  0000-0002-7028-4956

ISSN: 2072-4292
________________________________________
第 167 条,共 322 条
标题: Shaping the on-axis intensity profile of generalized Bessel beams by iterative optimization methods
作者: Li, RZ (Li, Runze); Yu, XH (Yu, Xianghua); Peng, T (Peng, Tong); Yang, YL (Yang, Yanlong); Yao, BL (Yao, Baoli); Zhang, CM (Zhang, Chunmin); Ye, T (Ye, Tong)
来源出版物: JOURNAL OF OPTICS 卷: 20 期: 8 文献号: 085603 DOI: 10.1088/2040-8986/aace46 出版年: JUN 2018
摘要: The Bessel beam belongs to a typical class of non-diffractive optical fields that are characterized by their invariant transverse profiles with the beam propagation. The extended and uniformed intensity profile in the axial direction is of great interest in many applications. However, ideal Bessel beams only rigorously exist in theory; the Bessel beams generated in the experiment are always quasi-Bessel beams with finite focal extensions and varying intensity profiles along the propagation axis. The ability to shape the on-axis intensity profile to meet specific needs is essential for many applications. Here, we demonstrate an iterative optimization based approach to engineer the on-axis intensity of Bessel beams through design and fine-tune processes. Starting with a standard axicon phase mask, the design process uses the computed on-axis beam profile as a feedback in the iterative optimization process, which searches for the optimal radial phase distribution that can generate a so-called generalized Bessel beam with the desired on-axis intensity profile. The fine-tune process repeats the optimization processing by using the adjusted target on-axis profile according to the measured one. Our proposed method has been demonstrated in engineering several quasi-Bessel beams with customized on-axis profiles. The high accuracy and high energy throughput merit its use in many applications. This method is also suitable to engineer higher-order Bessel beams by adding appropriate vortex phases into the designed phase mask.
入藏号: WOS:000437868000001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Xianghua                  0000-0002-7447-1396

ISSN: 2040-8978
eISSN: 2040-8986
________________________________________
第 168 条,共 322 条
标题: Classification and Discrimination of Martian-Related Minerals Using Spectral Fusion Methods
作者: Xu, WJ (Xu Wei-jie); Wu, ZC (Wu Zhong-chen); Zhu, XP (Zhu Xiang-ping); Zhang, J (Zhang Jiang); Ling, ZC (Ling Zong-cheng); Ni, YH (Ni Yu-heng); Guo, KC (Guo Kai-chen)
来源出版物: SPECTROSCOPY AND SPECTRAL ANALYSIS 卷: 38 期: 6 页: 1926-1932 DOI: 10.3964/j.issn.1000-0593(2018)06-1926-07 出版年: JUN 2018
摘要: Multi-source data fusion is a powerful method to combine data from multiple sources to improve the potential values and interpretation performances of the source data. Multi-payload collaborative analysis is regularly used to detect the same target in planetary exploration. Therefore, it is of great significance and potential application to use spectral fusion to establish a more accurate and robust clustering analysis model for Martian minerals identification. In this paper, the spectral characteristics of the main Martian-related minerals were analyzed by using both visible near-infrared (Vis-NIR) reflectance spectroscopy and Raman spectroscopy. And some data pre-processing methods such as baseline correction, Savitzky-Golay smoothing, standard normal variate (SNV) scaling were used to produce a high -quality representation of the spectral data. Firstly, the information rich spectral bands with higher signal-to-noise ratio and less overlapping were selected (i.e., Vis-NIR: 430 similar to 2 430 nm; Raman: 130 similar to 1 100 cm(-1)) for the clustering analysis. Secondly, soft independent method of class analogy (SIMCA) and principal component analysis-K-nearest neighbor (PCA-KNN), were respectively built based on selected Vis-NIR, Raman and two kinds of their fusion data( i.e., coaddition fusion and concatenation fusion), respectively. The accuracy of SIMCA model was enhanced from 72. 6% (Vis-NIR) and 90. 7% (Raman) to 96. 3% (coaddition fusion) and 98. 1% (concatenation fusion). The accuracy of PCA-KNN model was improved from 68. 9% (Vis-NIR) and 72. 9% (Raman) to 80. 3% (coaddition fusion) and 92. 6% (concatenation fusion), respectively. The results indicate that the fused Raman/Vis-NIR data can improve the classification model's accuracy of Martian-related minerals which will lay the foundation of quick rock classification for future Mars exploration.
入藏号: WOS:000435531000048
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Ling, Zongcheng         X-8076-2019         

ISSN: 1000-0593
________________________________________
第 169 条,共 322 条
标题: Automatic analysis of bioresorbable vascular scaffolds in intravascular optical coherence tomography images
作者: Cao, Y (Cao, Yihui); Jin, QH (Jin, Qinhua); Lu, YF (Lu, Yifeng); Jing, J (Jing, Jing); Chen, YD (Chen, Yundai); Yin, QY (Yin, Qinye); Qin, XJ (Qin, Xianjing); Li, JA (Li, Jianan); Zhu, R (Zhu, Rui); Zhao, W (Zhao, Wei)
来源出版物: BIOMEDICAL OPTICS EXPRESS 卷: 9 期: 6 页: 2495-2510 DOI: 10.1364/BOE.9.002495 出版年: JUN 1 2018
摘要: The bioresorbable vascular scaffold (BVS) is a new generation of bioresorbable scaffold (BRS) for the treatment of coronary artery disease. A potential challenge of BVS is malapposition, which may possibly lead to late stent thrombosis. It is therefore important to conduct malapposition analysis right after stenting. Since an intravascular optical coherence tomography (IVOCT) image sequence contains thousands of BVS struts, manual analysis is labor intensive and time consuming. Computer-based automatic analysis is an alternative, but faces some difficulties due to the interference of blood artifacts and the uncertainty of the struts number, position and size. In this paper, we propose a novel framework for a struts malapposition analysis that breaks down the problem into two steps. Firstly, struts are detected by a cascade classifier trained by AdaBoost and a region of interest (ROI) is determined for each strut to completely contain it. Then, strut boundaries are segmented within ROIs through dynamic programming. Based on the segmentation result, malapposition analysis is conducted automatically. Tested on 7 pullbacks labeled by an expert, our method correctly detected 91.5% of 5821 BVS struts with 12.1% false positives. The average segmentation Dice coefficient for correctly detected struts was 0.81. The time consumption for a pullback is 15 sec on average. We conclude that our method is accurate and efficient for BVS strut detection and segmentation, and enables automatic BVS malapposition analysis in IVOCT images. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000433954500002
PubMed ID: 30258668
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
chen, yundai         I-4353-2019         0000-0003-2252-8992

ISSN: 2156-7085
________________________________________
第 170 条,共 322 条
标题: Frequency-degenerate phase-sensitive optical parametric amplification based on four-wave mixing in graphene-silicon slot waveguide
作者: Li, Z (Li, Zhen); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu); Han, J (Han, Jing)
来源出版物: APPLIED PHYSICS EXPRESS 卷: 11 期: 6 文献号: 062201 DOI: 10.7567/APEX.11.062201 出版年: JUN 2018
摘要: The phase-sensitive amplification process of a hybrid graphene-silicon (HyGS) slot waveguide with trilayers of graphene is investigated in this paper. Numerical simulation shows that a relatively high extinction ratio (42 dB) is achieved, because of the ultrahigh nonlinear coefficients, with a waveguide length of only 680 mu m. In addition, the graphene layer provides the possibility of modulating the phase status and gain of the output signal. This study is expected to be highly beneficial to applications such as integrated optics and graphene-related active optical devices. (C) 2018 The Japan Society of Applied Physics
入藏号: WOS:000431405200001
ISSN: 1882-0778
eISSN: 1882-0786
________________________________________
第 171 条,共 322 条
标题: Subspace clustering guided convex nonnegative matrix factorization
作者: Cui, GS (Cui, Guosheng); Li, XL (Li, Xuelong); Dong, YS (Dong, Yongsheng)
来源出版物: NEUROCOMPUTING 卷: 292 页: 38-48 DOI: 10.1016/j.neucom.2018.02.067 出版年: MAY 31 2018
摘要: As one of the most important information of the data, the geometry structure information is usually modeled by a similarity graph to enforce the effectiveness of nonnegative matrix factorization (NMF). However, pairwise distance based graph is sensitive to noise and can not capture the subspace structure of the data. Reconstruction coefficients based graph can capture the subspace structure of the data, but the procedure of building the representation based graph is usually independent to the framework of NMF. To address this issue, a novel subspace clustering guided convex nonnegative matrix factorization (SC-CNMF) is proposed. In this NMF framework, the nonnegative subspace clustering is incorporated to learning the representation based graph, and meanwhile, a convex nonnegative matrix factorization is also updated simultaneously. To tackle the noise influence of the dataset, only k largest entries of each representation are kept in the subspace clustering. To capture the complicated geometry structure of the data, multiple centroids are also introduced to describe each cluster. Additionally, a row constraint is used to remove the relevance among the rows of the encoding matrix, which can help to improve the clustering performance of the proposed model. For the proposed NMF framework, two different objective functions with different optimizing schemes are designed. Image clustering experiments are conducted to demonstrate the effectiveness of the proposed methods on several datasets and compared with some related works based on NMF together with k-means clustering method and PCA as baseline. (c) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000429321400003
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 172 条,共 322 条
标题: Hexagonal boron nitride nanosheets incorporated antireflective silica coating with enhanced laser-induced damage threshold
作者: Wang, J (Wang, Jing); Li, CH (Li, Chunhong); Hu, WJ (Hu, Wenjie); Han, W (Han, Wei); Zhu, QH (Zhu, Qihua); Xu, Y (Xu, Yao)
来源出版物: HIGH POWER LASER SCIENCE AND ENGINEERING 卷: 6 文献号: e26 DOI: 10.1017/hpl.2018.16 出版年: MAY 30 2018
摘要: Boron nitride (BN) nanosheets incorporated silica antireflective (AR) coating was successfully prepared on fused silica substrate to improve the antilaser-damage ability of transmissive optics used in high-power laser systems. The BN nanosheets were obtained by urea assisted solid exfoliation, and then incorporated into basic-catalyzed silica sols without any further treatment. The transmission electron microscope (TEM) images indicated that the BN nanosheets generally consisted of 2-10 layers. The antireflective BN/SiO2 coating exhibited excellent transmittance as high as 99.89% at 351 nm wavelength on fused silica substrate. The thermal conductivity 0.135 W . m(-1) . K-1 of the BN/SiO2 coating with 10% BN addition was about 23% higher than 0.11 W . m(-1) . K-1 of the pure SiO2 AR coating. The laser-induced damage threshold (LIDT) of that BN/SiO2 coating is also 23.1% higher than that of pure SiO2 AR coating. This research provides a potential application of BN/SiO2 coatings in high-power laser systems.
入藏号: WOS:000433536300001
ISSN: 2095-4719
eISSN: 2052-3289
________________________________________
第 173 条,共 322 条
标题: Changes of phase structure of a paraxial beam due to spin-orbit coupling
作者: Li, HH (Li, Hehe); Wang, JG (Wang, Jingge); Tang, MM (Tang, Miaomiao); Li, XZ (Li, Xinzhong); Tang, J (Tang, Jie)
来源出版物: PHYSICAL REVIEW A 卷: 97 期: 5 文献号: 053843 DOI: 10.1103/PhysRevA.97.053843 出版年: MAY 29 2018
摘要: We analytically derive an expression for the optical field describing the spin Hall effect of a paraxial Gaussian beam in a lenslike inhomogeneous medium using the matrix optics method. Interestingly, we found changes in the phase structure and rotation of the polarization of the Gaussian beam induced by spin-orbit coupling, in addition to a polarization-dependent transverse deflection of the entire beam. This rotation of the polarization of the beam is not the result of the Berry phase. In addition, we show that the intrinsic optical angular momentum density of the beam is changed due to the spin-orbit coupling, and we also know that polarization-dependent rotation of the beam occurs when a circularly polarized nonaxisymmetric beam propagates in a lenslike inhomogeneous medium. Our results provide further potential applications of the spin Hall effect of light in optical signal processing.
入藏号: WOS:000433286200024
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xinzhong         P-7966-2018         0000-0002-6426-4043

ISSN: 2469-9926
eISSN: 2469-9934
________________________________________
第 174 条,共 322 条
标题: Orbit-induced localized spin angular momentum in strong focusing of optical vectorial vortex beams
作者: Li, MM (Li, Manman); Cai, YA (Cai, Yanan); Yan, SH (Yan, Shaohui); Liang, YS (Liang, Yansheng); Zhang, P (Zhang, Peng); Yao, BL (Yao, Baoli)
来源出版物: PHYSICAL REVIEW A 卷: 97 期: 5 文献号: 053842 DOI: 10.1103/PhysRevA.97.053842 出版年: MAY 29 2018
摘要: Light beams may carry optical spin or orbital angular momentum, or both. The spin and orbital parts manifest themselves by the ellipticity of the state of polarization and the vortex structure of phase of light beams, separately. Optical spin and orbit interaction, arising from the interaction between the polarization and the spatial structure of light beams, has attracted enormous interest recently. The optical spin-to-orbital angular momentum conversion under strong focusing is well known, while the converse process, orbital-to-spin conversion, has not been reported so far. In this paper, we predict in theory that the orbital angular momentum can induce a localized spin angular momentum in strong focusing of a spin-free azimuthal polarization vortex beam. This localized longitudinal spin of the focused field can drive the trapped particle to spin around its own axis. This investigation provides a new degree of freedom for spinning particles by using a vortex phase, which may have considerable potentials in optical spin and orbit interaction, light-beam shaping, or optical manipulation.
入藏号: WOS:000433286200023
ISSN: 2469-9926
eISSN: 2469-9934
________________________________________
第 175 条,共 322 条
标题: Design of an adjustable bipod flexure for a large-aperture mirror of a space camera
作者: Liu, B (Liu, Bei); Wang, W (Wang, Wei); Qu, YJ (Qu, Yan-Jun); Li, XP (Li, Xu-Peng); Wang, X (Wang, Xiao); Zhao, H (Zhao, Hui)
来源出版物: APPLIED OPTICS 卷: 57 期: 15 页: 4048-4055 DOI: 10.1364/AO.57.004048 出版年: MAY 20 2018
摘要: An adjustable bipod flexure (ABF) technique for a large-aperture mirror of a space camera is presented. The proposed flexure mount can decrease the surface distortions caused by the machining error and the assembly error of the mirror assembly (MA) in a horizontal optical testing layout. Through the analysis of the compliance matrix of conventional bipod flexure, the positional relationship between the rotation center and the apex of the flexure is investigated. Then, the principle of the adjustable flexure, known as the trapezoidal switching principle, is proposed based on the analysis result. The structure and application of the flexure are also described. The optical performance of the mirror mounted by the adjustable flexures in different misalignments was performed using finite element methods. The result shows that the astigmatic aberration due to gravity is effectively reduced by adjusting the mount, and the root-mean-square value of the mirror can be minimized with the misalignment between the flexure pivot and the neutral plane minimized. New monolithic bipod flexures, based on the optimal regulating variable according to the measurement results, are manufactured to replace the ABFs to secure the mirror's safety against launch loads. Modal analysis verified the mechanical safety of the MA with respect to the new monolithic flexures. (C) 2018 Optical Society of America
入藏号: WOS:000432497400009
PubMed ID: 29791378
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 176 条,共 322 条
标题: A novel near-infrared nanomaterial with high quantum efficiency and its applications in real time in vivo imaging
作者: Cui, XX (Cui, X. X.); Fan, Q (Fan, Q.); Shi, SJ (Shi, S. J.); Wen, WH (Wen, W. H.); Chen, DF (Chen, D. F.); Guo, HT (Guo, H. T.); Xu, YT (Xu, Y. T.); Gao, F (Gao, F.); Nie, RZ (Nie, R. Z.); Ford, HD (Ford, Harold D.); Tang, GH (Tang, Gordon H.); Hou, CQ (Hou, C. Q.); Peng, B (Peng, B.)
来源出版物: NANOTECHNOLOGY 卷: 29 期: 20 文献号: 205705 DOI: 10.1088/1361-6528/aab2fa 出版年: MAY 18 2018
摘要: Fluorescence imaging signal is severely limited by the quantum efficiency and emission wavelength. To overcome these challenges, novel NIR-emitting K5NdLi2F10 nanoparticles under NIR excitation was introduced as fluorescence imaging probe for the first time. The photostability of K5NdLi2F10 nanoparticles in the water, phosphate buffer saline, fetal bovine serum and living mice was investigated. The fluorescence signal was detected with depths of 3.5 and 2.0 cm in phantom and pork tissue, respectively. Fluorescence spectrum with a significant signal-to-background ratio of 10:1 was captured in living mice. Moreover, clear NIR images were virtualized for the living mice after intravenous injection. The imaging ability of nanoparticles in tumor-beard mice were evaluated, the enrichment of K5NdLi2F10 nanoparticles in tumor site due to the enhanced permeability and retention effect was confirmed. The systematic studies of toxicity, bio-distribution and in-vivo dynamic imaging suggest that these materials give high biocompatibility and low toxicity. These NIR-emitting nanoparticles with high quantum efficiency, high penetration and low toxicity might facilitate tumor identification in deep tissues more sensitively.
入藏号: WOS:000428270900002
PubMed ID: 29488904
ISSN: 0957-4484
eISSN: 1361-6528
________________________________________
第 177 条,共 322 条
标题: Improved force prediction model for grinding Zerodur based on the comprehensive material removal mechanism
作者: Sun, GY (Sun, Guoyan); Zhao, LL (Zhao, Lingling); Zhao, QL (Zhao, Qingliang); Gao, LM (Gao, Limin)
来源出版物: APPLIED OPTICS 卷: 57 期: 14 页: 3704-3713 DOI: 10.1364/AO.57.003704 出版年: MAY 10 2018
摘要: There have been few investigations dealing with the force model on grinding brittle materials. However, the dynamic material removal mechanisms have not yet been sufficiently explicated through the grain-workpiece interaction statuses while considering the brittle material characteristics. This paper proposes an improved grinding force model for Zerodur, which contains ductile removal force, brittle removal force, and frictional force, corresponding to the ductile and brittle material removal phases, as well as the friction process, respectively. The critical uncut chip thickness alpha(gc) of brittle-ductile transition and the maximum uncut chip thickness alpha(gmax) of a single abrasive grain are calculated to identify the specified material removal mode, while the comparative result between alpha(gmax) and alpha(gc) can be applied to determine the selection of effective grinding force components. Subsequently, indentation fracture tests are carried out to acquire accurate material mechanical properties of Zerodur in establishing the brittle removal force model. Then, the experiments were conducted to derive the coefficients in the grinding force prediction model. Simulated through this model, correlations between the grinding force and grinding parameters can be predicted. Finally, three groups of grinding experiments are carried out to validate the mathematical grinding force model. The experimental results indicate that the improved model is capable of predicting the realistic grinding force accurately with the relative mean errors of 6.04% to the normal grinding force and 7.22% to the tangential grinding force, respectively. (C) 2018 Optical Society of America.
入藏号: WOS:000431880000011
PubMed ID: 29791334
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 178 条,共 322 条
标题: Hough-space-based hypothesis generation and hypothesis verification for 3D object recognition and 6D pose estimation
作者: Zhou, W (Zhou, Wei); Ma, CW (Ma, Caiwen); Kuijper, A (Kuijper, Arjan)
来源出版物: COMPUTERS & GRAPHICS-UK 卷: 72 页: 122-134 DOI: 10.1016/j.cag.2018.01.011 出版年: MAY 2018
摘要: Hypothesis Generation (HG) and Hypothesis Verification (HV) play an important role in 3D objection recognition. However, performing 3D object recognition in cluttered scenes using HG and HV still remains a largely unsolved problem. High False Positive (FP) in HG and HV stages are witnessed due to clutter and occlusion, which will further affect the final accuracy of recognition. To address these problems, we propose a novel Hough-space-based HG approach for extracting hypotheses. Differently from the existing methods, our approach is based on a Hough space which adopts a self-adapted measure to generate hypotheses. Based on this, a novel HV-based method is proposed to verify the hypotheses obtained from HG procedures. The proposed method is evaluated on four public benchmark datasets to verify its performance. Experiments show that our approach outperforms state-of-the-art methods, and obtains a higher recognition rate without sacrificing precision both at high FP rates and high occlusion rates. (C) 2018 Elsevier Ltd. All rights reserved.
入藏号: WOS:000431158300012
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Kuijper, Arjan         A-7814-2012         0000-0002-6413-0061
Zhou, Wei                  0000-0001-8328-3736

ISSN: 0097-8493
eISSN: 1873-7684
________________________________________
第 179 条,共 322 条
标题: Perceptually Aware Image Retargeting for Mobile Devices
作者: Zhou, YZ (Zhou, Yinzuo); Zhang, LM (Zhang, Luming); Zhang, C (Zhang, Chao); Li, P (Li, Ping); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON IMAGE PROCESSING 卷: 27 期: 5 页: 2301-2313 DOI: 10.1109/TIP.2017.2779272 出版年: MAY 2018
摘要: Retargeting aims at adapting an original high-resolution photograph/video to a low-resolution screen with an arbitrary aspect ratio. Conventional approaches are generally based on desktop PCs, since the computation might be intolerable for mobile platforms (especially when retargeting videos). Typically, only low-level visual features are exploited, and human visual perception is not well encoded. In this paper, we propose a novel retargeting framework that rapidly shrinks a photograph/video by leveraging human gaze behavior. Specifically, we first derive a geometry-preserving graph ranking algorithm, which efficiently selects a few salient object patches to mimic the human gaze shifting path (GSP) when viewing a scene. Afterward, an aggregation-based CNN is developed to hierarchically learn the deep representation for each GSP. Based on this, a probabilistic model is developed to learn the priors of the training photographs that are marked as aesthetically pleasing by professional photographers. We utilize the learned priors to efficiently shrink the corresponding GSP of a retargeted photograph/video to maximize its similarity to those from the training photographs. Extensive experiments have demonstrated that: 1) our method requires less than 35 ms to retarget a 1024x768 photograph (or a 1280x720 video frame) on popular iOS/Android devices, which is orders of magnitude faster than the conventional retargeting algorithms; 2) the retargeted photographs/videos produced by our method significantly outperform those of its competitors based on a paired-comparison-based user study; and 3) the learned GSPs are highly indicative of human visual attention according to the human eye tracking experiments.
入藏号: WOS:000426272000017
PubMed ID: 29451495
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1057-7149
eISSN: 1941-0042
________________________________________
第 180 条,共 322 条
标题: Unsupervised Salient Object Detection via Inferring From Imperfect Saliency Models
作者: Quan, R (Quan, Rong); Han, JW (Han, Junwei); Zhang, DW (Zhang, Dingwen); Nie, FP (Nie, Feiping); Qian, XM (Qian, Xueming); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON MULTIMEDIA 卷: 20 期: 5 页: 1101-1112 DOI: 10.1109/TMM.2017.2763780 出版年: MAY 2018
摘要: Visual saliency detection has become an active research direction in recent years. A large number of saliency models, which can automatically locate objects of interest in images, have been developed. As these models take advantage of different kinds of prior assumptions, image features, and computational methodologies, they have their own strengths and weaknesses and may cope with only one or a few types of images well. Inspired by these facts, this paper proposes a novel salient object detection approach with the idea of inferring a superior model from a variety of previous imperfect saliency models via optimally leveraging the complementary information among them. The proposed approach mainly consists of three steps. First, a number of existing unsupervised saliency models are adopted to provide weak/imperfect saliency predictions for each region in the image. Then, a fusion strategy is used to fuse each image region's weak saliency predictions into a strong one by simultaneously considering the performance differences among various weak predictions and various characteristics of different image regions. Finally, a local spatial consistency constraint that ensures high similarity of the saliency labels for neighboring image regions with similar features is proposed to refine the results. Comprehensive experiments on five public benchmark datasets and comparisons with a number of state-of-the-art approaches can demonstrate the effectiveness of the proposed work.
入藏号: WOS:000430728400007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
zhang, dingwen         R-3463-2019         0000-0001-8369-8886
Nie, Feiping         B-3039-2012         
Nie, Feiping                  0000-0002-0871-6519
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1520-9210
eISSN: 1941-0077
________________________________________
第 181 条,共 322 条
标题: Convolution in Convolution for Network in Network
作者: Pang, YW (Pang, Yanwei); Sun, ML (Sun, Manli); Jiang, XH (Jiang, Xiaoheng); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 5 页: 1587-1597 DOI: 10.1109/TNNLS.2017.2676130 出版年: MAY 2018
摘要: Network in network (NiN) is an effective instance and an important extension of deep convolutional neural network consisting of alternating convolutional layers and pooling layers. Instead of using a linear filter for convolution, NiN utilizes shallow multilayer perceptron (MLP), a nonlinear function, to replace the linear filter. Because of the powerfulness of MLP and 1 x 1 convolutions in spatial domain, NiN has stronger ability of feature representation and hence results in better recognition performance. However, MLP itself consists of fully connected layers that give rise to a large number of parameters. In this paper, we propose to replace dense shallow MLP with sparse shallow MLP. One or more layers of the sparse shallow MLP are sparely connected in the channel dimension or channel-spatial domain. The proposed method is implemented by applying unshared convolution across the channel dimension and applying shared convolution across the spatial dimension in some computational layers. The proposed method is called convolution in convolution (CiC). The experimental results on the CIFAR10 data set, augmented CIFAR10 data set, and CIFAR100 data set demonstrate the effectiveness of the proposed CiC method.
入藏号: WOS:000430729100016
PubMed ID: 28328517
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 182 条,共 322 条
标题: SCE: A Manifold Regularized Set-Covering Method for Data Partitioning
作者: Li, XL (Li, Xuelong); Lu, QM (Lu, Quanmao); Dong, YS (Dong, Yongsheng); Tao, DC (Tao, Dacheng)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 5 页: 1760-1773 DOI: 10.1109/TNNLS.2017.2682179 出版年: MAY 2018
摘要: Cluster analysis plays a very important role in data analysis. In these years, cluster ensemble, as a cluster analysis tool, has drawn much attention for its robustness, stability, and accuracy. Many efforts have been done to combine different initial clustering results into a single clustering solution with better performance. However, they neglect the structure information of the raw data in performing the cluster ensemble. In this paper, we propose a Structural Cluster Ensemble (SCE) algorithm for data partitioning formulated as a set-covering problem. In particular, we construct a Laplacian regularized objective function to capture the structure information among clusters. Moreover, considering the importance of the discriminative information underlying in the initial clustering results, we add a discriminative constraint into our proposed objective function. Finally, we verify the performance of the SCE algorithm on both synthetic and real data sets. The experimental results show the effectiveness of our proposed method SCE algorithm.
入藏号: WOS:000430729100029
PubMed ID: 28391209
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 183 条,共 322 条
标题: Efficient kNN Classification With Different Numbers of Nearest Neighbors
作者: Zhang, SC (Zhang, Shichao); Li, XL (Li, Xuelong); Zong, M (Zong, Ming); Zhu, XF (Zhu, Xiaofeng); Wang, RL (Wang, Ruili)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 5 页: 1774-1785 DOI: 10.1109/TNNLS.2017.2673241 出版年: MAY 2018
摘要: k nearest neighbor (kNN) method is a popular classification method in data mining and statistics because of its simple implementation and significant classification performance. However, it is impractical for traditional kNN methods to assign a fixed k value (even though set by experts) to all test samples. Previous solutions assign different k values to different test samples by the cross validation method but are usually time-consuming. This paper proposes a kTree method to learn different optimal k values for different test/new samples, by involving a training stage in the kNN classification. Specifically, in the training stage, kTree method first learns optimal k values for all training samples by a new sparse reconstruction model, and then constructs a decision tree (namely, kTree) using training samples and the learned optimal k values. In the test stage, the kTree fast outputs the optimal k value for each test sample, and then, the kNN classification can be conducted using the learned optimal k value and all training samples. As a result, the proposed kTree method has a similar running cost but higher classification accuracy, compared with traditional kNN methods, which assign a fixed k value to all test samples. Moreover, the proposed kTree method needs less running cost but achieves similar classification accuracy, compared with the newly kNN methods, which assign different k values to different test samples. This paper further proposes an improvement version of kTree method (namely, k*Tree method) to speed its test stage by extra storing the information of the training samples in the leaf nodes of kTree, such as the training samples located in the leaf nodes, their kNNs, and the nearest neighbor of these kNNs. We call the resulting decision tree as k*Tree, which enables to conduct kNN classification using a subset of the training samples in the leaf nodes rather than all training samples used in the newly kNN methods. This actually reduces running cost of test stage. Finally, the experimental results on 20 real data sets showed that our proposed methods (i.e., kTree and k*Tree) are much more efficient than the compared methods in terms of classification tasks.
入藏号: WOS:000430729100030
PubMed ID: 28422666
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
zong, ming         Q-7348-2019         
Zhu, Xiaofeng                  0000-0001-6840-0578
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 184 条,共 322 条
标题: Effect of machining parameter on femtosecond laser drilling processing on SiC/SiC composites
作者: Liu, YS (Liu, Yongsheng); Zhang, RH (Zhang, Ruoheng); Li, WN (Li, Weinan); Wang, J (Wang, Jing); Yang, XJ (Yang, Xiaojun); Cheng, LF (Cheng, Laifei); Zhang, LT (Zhang, Litong)
来源出版物: INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 卷: 96 期: 5-8 页: 1795-1811 DOI: 10.1007/s00170-017-1163-7 出版年: MAY 2018
摘要: Due to the unique properties of femtosecond laser in precision machining, femtosecond laser was utilized for irradiation on SiC/SiC composites. Effects of different processing parameters, including the spot overlap ratio, helical line overlap ratio, laser processing power, as well as processing steps, were discussed in detail. The results indicated that the parameters above had significant effect on machining of SiC/SiC composites. The surface morphology and geometry of the micro-holes were investigated under different parameters, and the corresponding formation mechanism was discussed in detail. It was believed that both the spot and helical line overlap ratio had great effect on the quality of the micro-holes and would be responsible to the depth of micro-holes. Besides, it is indicated that the higher processing power will lead to a better quality of surface morphology and machining results. In micro-hole drilling process, debris and fragments were observed within the micro-holes, and XPS analysis showed that there existed Si-O bonds and Si-C bonds, indicating that the oxidation during processing was incomplete. In addition, the effect of feeding speeds on geometry and depth of the micro-holes were discussed as well.
入藏号: WOS:000430539100028
ISSN: 0268-3768
eISSN: 1433-3015
________________________________________
第 185 条,共 322 条
标题: Hyperspectral Anomaly Detection via Discriminative Feature Learning with Multiple-Dictionary Sparse Representation
作者: Ma, DD (Ma, Dandan); Yuan, Y (Yuan, Yuan); Wang, Q (Wang, Qi)
来源出版物: REMOTE SENSING 卷: 10 期: 5 文献号: 745 DOI: 10.3390/rs10050745 出版年: MAY 2018
摘要: Most hyperspectral anomaly detection methods directly utilize all the original spectra to recognize anomalies. However, the inherent characteristics of high spectral dimension and complex spectral correlation commonly make their detection performance unsatisfactory. Therefore, an effective feature extraction technique is necessary. To this end, this paper proposes a novel anomaly detection method via discriminative feature learning with multiple-dictionary sparse representation. Firstly, a new spectral feature selection framework based on sparse presentation is designed, which is closely guided by the anomaly detection task. Then, the representative spectra which can significantly enlarge anomaly's deviation from background are picked out by minimizing residues between background spectrum reconstruction error and anomaly spectrum recovery error. Finally, through comprehensively considering the virtues of different groups of representative features selected from multiple dictionaries, a global multiple-view detection strategy is presented to improve the detection accuracy. The proposed method is compared with ten state-of-the-art methods including LRX, SRD, CRD, LSMAD, RSAD, BACON, BACON-target, GRX, GKRX, and PCA-GRX on three real-world hyperspectral images. Corresponding to each competitor, it has the average detection performance improvement of about respectively. Extensive experiments demonstrate its superior performance in effectiveness and efficiency.
入藏号: WOS:000435198400087
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wang, Qi                  0000-0002-7028-4956

ISSN: 2072-4292
________________________________________
第 186 条,共 322 条
标题: Etracker: A Mobile Gaze-Tracking System with Near-Eye Display Based on a Combined Gaze-Tracking Algorithm
作者: Li, B (Li, Bin); Fu, H (Fu, Hong); Wen, DS (Wen, Desheng); Lo, WL (Lo, WaiLun)
来源出版物: SENSORS 卷: 18 期: 5 文献号: 1626 DOI: 10.3390/s18051626 出版年: MAY 2018
摘要: Eye tracking technology has become increasingly important for psychological analysis, medical diagnosis, driver assistance systems, and many other applications. Various gaze-tracking models have been established by previous researchers. However, there is currently no near-eye display system with accurate gaze-tracking performance and a convenient user experience. In this paper, we constructed a complete prototype of the mobile gaze-tracking system 'Etracker' with a near-eye viewing device for human gaze tracking. We proposed a combined gaze-tracking algorithm. In this algorithm, the convolutional neural network is used to remove blinking images and predict coarse gaze position, and then a geometric model is defined for accurate human gaze tracking. Moreover, we proposed using the mean value of gazes to resolve pupil center changes caused by nystagmus in calibration algorithms, so that an individual user only needs to calibrate it the first time, which makes our system more convenient. The experiments on gaze data from 26 participants show that the eye center detection accuracy is 98% and Etracker can provide an average gaze accuracy of 0.53 degrees at a rate of 30-60 Hz.
入藏号: WOS:000435580300325
PubMed ID: 29783738
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
fu, hong                  0000-0003-2246-7552

eISSN: 1424-8220
________________________________________
第 187 条,共 322 条
标题: Guiding properties of proton-implanted Nd3+-doped phosphate glass waveguides
作者: Zhu, QF (Zhu, Qi-Feng); Wang, Y (Wang, Yue); Shen, JP (Shen, Jian-Ping); Guo, HT (Guo, Hai-Tao); Liu, CX (Liu, Chun-Xiao)
来源出版物: CHINESE PHYSICS B 卷: 27 期: 5 文献号: 054218 DOI: 10.1088/1674-1056/27/5/054218 出版年: MAY 2018
摘要: We report on the fabrication and properties of an optical waveguide in Nd-3+-doped phosphate glass. The planar waveguide was obtained by 550-keV proton implantation with a dose of 8.0xl0(16) ions/cm(2). The proton-glass interaction was simulated by the stopping and range of ions in matter (SRIM software). The characteristics of the waveguide including the refractive index profile and the near-field intensity distribution were studied by the reflectivity calculation method and the end-face coupling technique. The optical waveguide demonstrated multi-mode behavior at the wavelength of 632.8 nm. The propagation features of the proton-implanted Nd3+-doped phosphate glass waveguide shows its potential to operate as an integrated photonic device.
入藏号: WOS:000432666900018
ISSN: 1674-1056
eISSN: 1741-4199
________________________________________
第 188 条,共 322 条
标题: Study on Quality Identification of Macadamia nut Based on Convolutional Neural Networks and Spectral Features
作者: Du, J (Du Jian); Hu, BL (Hu Bing-liang); Liu, YZ (Liu Yong-zheng); Wei, CY (Wei Cui-yu); Zhang, G (Zhang Geng); Tang, XJ (Tang Xing-jia)
来源出版物: SPECTROSCOPY AND SPECTRAL ANALYSIS 卷: 38 期: 5 页: 1514-1519 DOI: 10.3964/j.issn.1000-0593(2018)05-1514-06 出版年: MAY 2018
摘要: Macadamia nut is easy to spoil after being stripped off because of the high level of oil in it. Most of the existing traditional methods are destructive which are difficult to satisfy the demand of non-destructive detection. As one of the widely used deep learning models, convolutional neural network (CNN) has stronger capabilities of feature extraction and model formulation than shallow learning methods and great potential for the application of spectral data. We studied suitable CNN architecture to extract spectral features of Macadamia based on Vis-NIRS analysis, and proposed an efficient non-destructive method to identify the quality of Macadamia. At first, we took three kinds of macadamia nut with different qualities (including better nut, worse nut and moldy nut) as the research object and analyzed the spectral information in the wavelength range of 500 similar to 2 100 nm. We introduced the concept of whitening in data preprocessing to strengthen the correlation difference. In the process of model training, we divided the sample into training set and prediction set randomly and then discussed the effects of different structure parameters, such as the number of convolution layer, size of convolution kernel, pooling type, number of neuron in full connection layer and activation function. We applied ReLU and Dropout to prevent over-fitting caused by lack of data. At last, through the analysis of the classification accuracy and computational efficiency, a CNN model of 6-layer structure was established: input layer-convolution layer-pooling layer-full connection layer(including 200 neurons)-full connection layer(including 100 neurons)-output layer. The results show that the final classification accuracy of the calibration set and prediction set reached 100%. This improved CNN model can fully learn the spectral features of macadamia and classify effectively. The combination of the deep learning theory and the spectral analysis method can identify the quality of macadamia accurately, and provide a new idea for the efficient, non-destructive, real-time, online detection of macadamia and other nuts.
入藏号: WOS:000432512000030
ISSN: 1000-0593
________________________________________
第 189 条,共 322 条
标题: Thermomechanical Behavior of Conduction-Cooled High-Power Diode Laser Arrays
作者: Nie, ZQ (Nie, Zhiqiang); Lu, Y (Lu, Yao); Chen, TQ (Chen, Tianqi); Zhang, P (Zhang, Pu); Wu, DH (Wu, Dihai); Wang, MP (Wang, Mingpei); Xiong, LL (Xiong, Lingling); Li, XN (Li, Xiaoning); Wang, ZF (Wang, Zhenfu); Liu, XS (Liu, Xingsheng)
来源出版物: IEEE TRANSACTIONS ON COMPONENTS PACKAGING AND MANUFACTURING TECHNOLOGY 卷: 8 期: 5 页: 818-829 DOI: 10.1109/TCPMT.2018.2820183 出版年: MAY 2018
摘要: Thermomechanical behavior has an important effect on reliability and lifetime of high-power diode lasers (HPDLs). Finite-element analysis (FEA) model and analytical solution model of the conduction-cooled package (CS) HPDL are established to analyze the thermomechanical behavior including normal stress, shearing stress, and displacement in reflowing process and working process. Moreover, in order to simulate and analyze the thermomechanical behavior in total process, reflowing thermal stress and displacement are considered as the residual stress and the initial condition of working process. We find that shearing stress is the origin of other thermomechanical behavior due to coefficient thermal expansion (CTE) mismatch, while both CTE mismatch and temperature gradient cause the thermal stress and displacement in working process. Although thermal stresses and displacement induced in reflowing process are larger than working process, the working process has great impact on smile and causes much worse total smile. The influence of different working temperatures on smile is also studied in total process with analytical solution, FEA, and experiment. For analytical solution, the total smile value is inversely proportional to the working temperature, while for FEA the smile value is proportional to the working temperature and FEA result accords with experimental result.
入藏号: WOS:000431915800014
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wang, Mingpei                  0000-0003-0163-3208
, Lu                  0000-0001-8149-4628

ISSN: 2156-3950
eISSN: 2156-3985
________________________________________
第 190 条,共 322 条
标题: Temperature dependence of Yb-doped superfluorescent fiber source
作者: Wu, P (Wu, Peng); Wang, YS (Wang, Yishan); Zhao, W (Zhao, Wei); Zhao, BY (Zhao, Baoyin); Miao, XF (Miao, Xiaofang); Li, Z (Li, Zhe); Gao, W (Gao, Wei); Zheng, JK (Zheng, Jinkun)
来源出版物: INFRARED PHYSICS & TECHNOLOGY 卷: 90 页: 48-52 DOI: 10.1016/j.infrared.2018.02.005 出版年: MAY 2018
摘要: The influence of temperature on the output spectra and power of Yb-doped superfluorescent fiber source are investigated through a temperature-dependent model. The model is composed of steady-state rate equations and temperature-dependent cross section functions. Simulation results indicated that with temperature varying from 0 degrees C to 100 degrees C, the central wavelengths of the forward and backward output spectra shift from 1061.8 nm to 1070.8 nm and from 1045.8 nm to 1068.8 nm, respectively. Meanwhile, the total output power has a 15.3% reduction. These trends are further verified experimentally. This study offers a concise way of acquiring a superfluorescent fiber source with different central wavelengths. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000431935500006
ISSN: 1350-4495
eISSN: 1879-0275
________________________________________
第 191 条,共 322 条
标题: Aberration correction in holographic optical tweezers using a high-order optical vortex
作者: Liang, YS (Liang, Yansheng); Cai, YA (Cai, Yanan); Wang, ZJ (Wang, Zhaojun); Lei, M (Lei, Ming); Cao, ZL (Cao, Zhiliang); Wang, Y (Wang, Yue); Li, MM (Li, Manman); Yan, SH (Yan, Shaohui); Bianco, PR (Bianco, Piero R.); Yao, BL (Yao, Baoli)
来源出版物: APPLIED OPTICS 卷: 57 期: 13 页: 3618-3623 DOI: 10.1364/AO.57.003618 出版年: MAY 1 2018
摘要: Holographic optical tweezers are a powerful optical trapping and manipulation tool in numerous applications such as life science and colloidal physics. However, imperfections in the spatial light modulator and optical components of the system will introduce detrimental aberrations to the system, thereby degrading the trapping performance significantly. To address this issue, we develop an aberration correction technique by using a high-order vortex as the correction metric. The optimal Zernike polynomial coefficients for quantifying the system aberrations are determined by comparing the distorted vortex and the ideal one. Efficiency of the proposed method is demonstrated by comparing the optical trap intensity distribution, trap stiffness, and particle dynamics in a Gaussian trap and an optical vortex trap, before and after aberration corrections. (C) 2018 Optical Society of America
入藏号: WOS:000431175200045
PubMed ID: 29726541
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 192 条,共 322 条
标题: Robust soliton crystals in a thermally controlled microresonator
作者: Wang, WQ (Wang, Weiqiang); Lu, ZZ (Lu, Zhizhou); Zhang, WF (Zhang, Wenfu); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Wang, LR (Wang, Leiran); Xie, XP (Xie, Xiaoping); Liu, ML (Liu, Mulong); Yang, QH (Yang, Qinghua); Wang, L (Wang, Lei); Zhao, JG (Zhao, Jianguo); Wang, GX (Wang, Guoxi); Sun, QB (Sun, Qibing); Liu, YS (Liu, Yuanshan); Wang, YS (Wang, Yishan); Zhao, W (Zhao, Wei)
来源出版物: OPTICS LETTERS 卷: 43 期: 9 页: 2002-2005 DOI: 10.1364/OL.43.002002 出版年: MAY 1 2018
摘要: We demonstrate robust soliton crystals generation with a fixed frequency pump laser through a thermoelectric-coolerbased thermal-tuning approach in a butterfly-packaged complementary-metal-oxide-semiconductor-compatible micro-resonator. Varieties of soliton crystal states, exhibiting "palm-like" optical spectra that result from the strong interactions between the dense soliton ensembles and reflect their temporal distribution directly, are experimentally observed by sweeping one cavity resonance across the pump frequency from the blue-detuned side by reducing the operating temperature of the resonator. Benefitting from the tiny intracavity energy change, repeatable interconversion between the chaotic modulation instability and stable soliton crystal states can be successfully achieved via simple tuning of the temperature or pump power, showing the easy accessibility and excellent stability of such soliton crystals. This work could facilitate microresonator-based optical frequency combs towards a portable, adjustable, and low-cost system while avoiding the requirements of delicate frequency-sweeping pump techniques. (C) 2018 Optical Society of America.
入藏号: WOS:000431179400016
PubMed ID: 29714731
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Yang, Qinghua                  0000-0003-4679-1621

ISSN: 0146-9592
eISSN: 1539-4794
________________________________________
第 193 条,共 322 条
标题: Efficient point-by-point Bragg gratings fabricated in embedded laser-written silica waveguides using ultrafast Bessel beams
作者: Zhang, G (Zhang, G.); Cheng, G (Cheng, G.); Bhuyan, M (Bhuyan, M.); D'Amico, C (D'Amico, C.); Stoian, R (Stoian, R.)
来源出版物: OPTICS LETTERS 卷: 43 期: 9 页: 2161-2164 DOI: 10.1364/OL.43.002161 出版年: MAY 1 2018
摘要: We demonstrate highly efficient Bragg gratings written point-by-point by sequential single-pulse ultrashort Bessel laser beams in laser photoinscribed single-mode waveguides in bulk fused silica. The use of chirped non-diffractive Bessel beams determines a strong Bragg resonance in a weak-to-strong transitional regime, augmenting to a record value of 40 dB/cm at 1550 nm in the third order. The Bessel-induced refractive index modulation is negative and localized to sub-micrometer (200 nm) transverse scales. The strong light confinement in Bessel beams ensuring uniform one-dimensional void conditions thus allows for enhanced precision in the Bragg grating waveguide design. We demonstrate flexible fabrication of multiplexed waveguide gratings for multiple and tunable spectral resonances. (C) 2018 Optical Society of America
入藏号: WOS:000431179400056
PubMed ID: 29714779
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Stoian, Razvan                  0000-0003-2107-9515
Zhang, Guodong                  0000-0001-9466-8105

ISSN: 0146-9592
eISSN: 1539-4794
________________________________________
第 194 条,共 322 条
标题: Self-locked orthogonal polarized dual comb in a microresonator
作者: Wang, WQ (Wang, Weiqiang); Zhang, WF (Zhang, Wenfu); Lu, ZZ (Lu, Zhizhou); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Yang, QH (Yang, Qinghua); Wang, L (Wang, Lei); Zhao, W (Zhao, Wei)
来源出版物: PHOTONICS RESEARCH 卷: 6 期: 5 页: 363-367 DOI: 10.1364/PRJ.6.000363 出版年: MAY 1 2018
摘要: Dual combs are an emerging tool to obtain unprecedented resolution, high sensitivity, ultrahigh accuracy, broad bandwidth, and ultrafast data updating rate in the fields of molecular spectroscopy, optical metrology, as well as optical frequency synthesis. The recent progress in chip-based microcombs has promoted the on-chip dual-comb measuring systems to a new phase attributed to the large frequency spacing and broad spectrum. In this paper, we demonstrate proof-of-concept dual-comb generation with orthogonal polarization in a single microresonator through pumping both the transverse-electric (TE) and transverse-magnetic (TM) modes simultaneously. The two orthogonal polarized pumps are self-oscillating in a fiber ring cavity. The generated dual comb exhibits excellent stability due to the intrinsic feedback mechanism of the self-locked scheme. The repetition rate of the two orthogonal combs is slightly different because of the mode spacing difference between the TE and TM modes. Such orthogonal polarized dual-combs could be a new comb source for out-of-lab applications in the fields of integrated spectroscopy, ranging measurement, optical frequency synthesis, and microwave comb generation. (C) 2018 Chinese Laser Press
入藏号: WOS:000431307600019
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Yang, Qinghua                  0000-0003-4679-1621

ISSN: 2327-9125
________________________________________
第 195 条,共 322 条
标题: Type-II micro-comb generation in a filter-driven four wave mixing laser [Invited]
作者: Bao, HL (Bao, Hualong); Cooper, A (Cooper, Andrew); Chu, ST (Chu, Sai T.); Moss, DJ (Moss, Dave J.); Morandotti, R (Morandotti, Roberto); Little, BE (Little, Brent E.); Peccianti, M (Peccianti, Marco); Pasquazi, A (Pasquazi, Alessia)
来源出版物: PHOTONICS RESEARCH 卷: 6 期: 5 页: B67-B73 DOI: 10.1364/PRJ.6.000B67 出版年: MAY 1 2018
摘要: We experimentally demonstrate the generation of highly coherent Type-II micro-combs based on a micro-resonator nested in a fiber cavity loop, known as the filter-driven four wave mixing (FD-FWM) laser scheme. In this system, the frequency spacing of the comb can be adjusted to integer multiples of the free-spectral range (FSR) of the nested micro-resonator by properly tuning the fiber cavity length. Sub-comb lines with single FSR spacing around the primary comb lines can be generated. Such a spectral emission is known as a "Type-II comb." Our system achieves a fully coherent output. This behavior is verified by numerical simulations. This study represents an important step forward in controlling and manipulating the dynamics of an FD-FWM laser.
入藏号: WOS:000431307600012
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Peccianti, Marco         F-7127-2011         0000-0001-8894-496X
Pasquazi, Alessia         J-8521-2014         0000-0003-3330-584X

ISSN: 2327-9125
________________________________________
第 196 条,共 322 条
标题: Photonic microwave true time delays for phased array antennas using a 49 GHz FSR integrated optical micro-comb source [Invited]
作者: Xu, XY (Xu, Xingyuan); Wu, JY (Wu, Jiayang); Nguyen, TG (Nguyen, Thach G.); Moein, T (Moein, Tania); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)
来源出版物: PHOTONICS RESEARCH 卷: 6 期: 5 页: B30-B36 DOI: 10.1364/PRJ.6.000B30 出版年: MAY 1 2018
摘要: We demonstrate significantly improved performance of a microwave true time delay line based on an integrated optical frequency comb source. The broadband micro-comb (over 100 nm wide) features a record low free spectral range (FSR) of 49 GHz, resulting in an unprecedented record high channel number (81 over the C band)-the highest number of channels for an integrated comb source used for microwave signal processing. We theoretically analyze the performance of a phased array antenna and show that this large channel count results in a high angular resolution and wide beam-steering tunable range. This demonstrates the feasibility of our approach as a competitive solution toward implementing integrated photonic true time delays in radar and communications systems. (C) 2018 Chinese Laser Press.
入藏号: WOS:000431307600008
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Nguyen, Thach                  0000-0002-8409-5638
Mitchell, Arnan         C-5017-2008         0000-0002-2463-2956

ISSN: 2327-9125
________________________________________
第 197 条,共 322 条
标题: Adjustable Elliptic Annular Optical Vortex Array
作者: Ma, HX (Ma, H. X.); Li, XZ (Li, X. Z.); Zhang, H (Zhang, H.); Tang, J (Tang, J.); Nie, ZG (Nie, Z. G.); Li, HH (Li, H. H.); Tang, MM (Tang, M. M.); Wang, JG (Wang, J. G.); Tai, YP (Tai, Y. P.); Wang, YS (Wang, Y. S.)
来源出版物: IEEE PHOTONICS TECHNOLOGY LETTERS 卷: 30 期: 9 页: 813-816 DOI: 10.1109/LPT.2018.2817643 出版年: MAY 1 2018
摘要: We present an elliptic annular optical vortex array (EOVA), whose annular eccentricity can be freely adjusted. The EOVA is generated by coherent superposition of two elliptic perfect optical vortices (EPOVs) with the same eccentricity. The vortex number and sign of the EOVA are determined by the difference of the topological charges (TCs) of these two EPOVs. Continuously increasing the initial phase difference between the EPOVs, each vortex of the EOVA can be rotated on the elliptic ring. Moreover, the birth process of a vortex is visualized by changing the TC of one of the EPOVs from an integer to the adjacent integer in steps of 0.1. This letter demonstrates a different spatial-structured optical vortex array, which is of significance in applications such as optical tweezers and micro-particle manipulation.
入藏号: WOS:000429677400013
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xinzhong         P-7966-2018         0000-0002-6426-4043
Ma, Haixiang                  0000-0001-9422-9372

ISSN: 1041-1135
eISSN: 1941-0174
________________________________________
第 198 条,共 322 条
标题: Tunable Wavelength-Selective Coupler Based on Microtapered Long-Period Fiber Gratings
作者: Kong, XD (Kong, Xudong); Ren, KL (Ren, Kaili); Ren, LY (Ren, Liyong); Liang, J (Liang, Jian); Ju, HJ (Ju, Haijuan); Xu, YP (Xu, Yiping)
来源出版物: IEEE PHOTONICS TECHNOLOGY LETTERS 卷: 30 期: 9 页: 821-824 DOI: 10.1109/LPT.2018.2818122 出版年: MAY 1 2018
摘要: In this letter, the wavelength-selective couplers (WSCs) constructed with two-and three-parallel microtapered long-period fiber gratings (MLPFGs) are experimentally demonstrated, respectively. The MLPFGs are fabricated by periodically tapering the standard single mode fibers. In WSCs constructed with two-parallel MLPFGs, the maximum peak coupling efficiency is similar to 10.1%, while in WSCs constructed with three-parallel MLPFGs, the maximum peak coupling efficiencies are similar to 2.9% and similar to 3.2% for two tapping fibers, respectively. Moreover, we propose an effective and convenient method to tune the WSCs. By simply twisting the WSCs constructed with two-parallel MLPFGs, the wavelength tunability of -0.01985 nm/degrees with a maximum wavelength tuning range of 6.8 nm is achieved, together with a good linear relationship of the shift at resonance wavelength versus the twist angle.
入藏号: WOS:000429677400015
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
ren, li yong         F-5518-2014         0000-0002-7547-7511

ISSN: 1041-1135
eISSN: 1941-0174
________________________________________
第 199 条,共 322 条
标题: Transition metal dichalcogenide (WS2 and MoS2) saturable absorbers for Q-switched Er-doped fiber lasers
作者: Li, L (Li, Lu); Lv, RD (Lv, Ruidong); Liu, SC (Liu, Sicong); Wang, X (Wang, Xi); Wang, YG (Wang, Yonggang); Chen, ZD (Chen, Zhendong); Wang, J (Wang, Jiang)
来源出版物: LASER PHYSICS 卷: 28 期: 5 文献号: 055106 DOI: 10.1088/1555-6611/aab24f 出版年: MAY 2018
摘要: This report demonstrates a stable Q-switched Er-doped fiber laser with MoS2 (WS2)-based saturable absorber (SA) in the net normal dispersion regime. The SA is obtained by mixing MoS2 (WS2) nanosheets with polyvinyl alcohol (PVA) into polystyrene cells, and then evaporating them to form MoS2 (WS2)/PVA film. The modulation depth values for MoS2/PVA and WS2/PVA are measured to be 2.7% and 2.1% respectively. Employing the MoS2 (WS2)/PVA film in the Er-doped fiber laser cavity, stable Q-switching operation is achieved with central wavelength of 1560 nm. The shortest pulse durations of the two Q-switched fiber lasers are, respectively, 3.97 and 3.71 mu s, and their maximum single pulse energies are measured to be 131.52 and 126.96 nJ. The experimental results clearly show that MoS2 (WS2) is a promising nonlinear material, and that improvements in Q-switching performance due to two SAs in the net normal dispersion regime might be helpful in the design of fiber lasers.
入藏号: WOS:000429895700002
ISSN: 1054-660X
eISSN: 1555-6611
________________________________________
第 200 条,共 322 条
标题: High precision linear frequency modulation ranging system based on semiconductor laser
作者: Xue, MY (Xue, Mingyuan); Gao, CX (Gao, Cunxiao); Niu, LQ (Niu, Linquan); Zhu, SL (Zhu, Shaolan); Guo, N (Guo, Na); Feng, L (Feng, Li); He, HD (He, Haodong)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 11 文献号: 1850136 DOI: 10.1142/S0217984918501361 出版年: APR 20 2018
摘要: Based on the linear frequency modulation (LFM) of semiconductor laser, a laser ranging system is built. The ranging precision of the system is about micron dimension with the repetition frequency of 100 kHz and a distance of 1-10 m. We analyzed the ranging precision experimentally. As the bandwidth increases, the ranging precision becomes higher and higher. When the bandwidth is fixed, as the distance increases, the signal-to-noise ratio (SNR) will decrease, which reduces the precision.
入藏号: WOS:000430393300011
ISSN: 0217-9849
eISSN: 1793-6640


第 201 条,共 322 条
标题: Numerical investigation of narrowband infrared absorber and sensor based on dielectric-metal metasurface
作者: Lu, XY (Lu, Xiaoyuan); Zhang, TY (Zhang, Tongyi); Wan, RG (Wan, Rengang); Xu, YT (Xu, Yongtao); Zhao, CH (Zhao, Changhong); Guo, S (Guo, Sheng)
来源出版物: OPTICS EXPRESS 卷: 26 期: 8 页: 10179-10187 DOI: 10.1364/OE.26.010179 出版年: APR 16 2018
摘要: Metasurfaces are investigated intensively for biophotonics applications due to their resonant wavelength flexibly tuned in the near infrared region specially matching biological tissues. Here, we present numerically a metasurface structure combining dielectric resonance with surface plasmon mode of a metal plane, which is a perfect absorber with a narrow linewidth 10 nm wide and quality factor 120 in the near infrared regime. As a sensor, its bulk sensitivity and bulk figure of merit reach respectively 840 nm/RIU and 84/RIU, while its surface sensitivity and surface figure of merit are respectively 1 and 0.1/nm. For different types of adsorbate layers with the same thickness of 8 tan, its surface sensitivity and figure of merit are respectively 32.3 and 3.2/RIU. The enhanced electric held is concentrated on top of dielectric patch ends and in the patch ends simultaneously. Results show that the presented structure has high surface (and bulk) sensing capability in sensing applications due to its narrow linewidth and deep modulation depth. This could pave a new route toward dielectric-metal metasurface in biosensing applications, such as early disease detections and designs of neural stem cell sensing platforms. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000430337700069
PubMed ID: 29715958
ISSN: 1094-4087
________________________________________
第 202 条,共 322 条
标题: Round-trip imaging through scattering media based on optical transmission matrix
作者: Zhuang, B (Zhuang, Bin); Xu, CF (Xu, Chengfang); Geng, Y (Geng, Yi); Zhao, GZ (Zhao, Guangzhi); Chen, H (Chen, Hui); He, ZQ (He, Zhengquan); Wu, ZX (Wu, Zhaoxin); Ren, LY (Ren, Liyong)
来源出版物: CHINESE OPTICS LETTERS 卷: 16 期: 4 文献号: 041102 DOI: 10.3788/COL201816.041102 出版年: APR 10 2018
摘要: Traditional one-way imaging methods become invalid when a target object is completely hidden behind scattering media. In this case, it has been much more challenging, since the light wave is distorted twice. To solve this problem, we propose an imaging method, so-called round-trip imaging, based on the optical transmission matrix of the scattering medium. We show that the object can be recovered directly from the distorted output wave, where no scanning is required during the imaging process. We predict that this method might improve the imaging speed and have potential application for real-time imaging.
入藏号: WOS:000429657500014
ISSN: 1671-7694
________________________________________
第 203 条,共 322 条
标题: Contour-aware network for semantic segmentation via adaptive depth
作者: Jiang, ZY (Jiang, Zhiyu); Yuan, Y (Yuan, Yuan); Wang, Q (Wang, Qi)
来源出版物: NEUROCOMPUTING 卷: 284 页: 27-35 DOI: 10.1016/j.neucom.2018.01.022 出版年: APR 5 2018
摘要: Semantic segmentation has been widely investigated for its important role in computer vision. However, some challenges still exist. The first challenge is how to perceive semantic regions with various attributes, which can result in unbalanced distribution of training samples. Another challenge is accurate semantic boundary determination. In this paper, a contour-aware network for semantic segmentation via adaptive depth is proposed which particularly exploits the power of adaptive-depth neural network and contour-aware neural network on pixel-level semantic segmentation. Specifically, an adaptive-depth model, which can adaptively determine the feedback and forward procedure of neural network, is constructed. Moreover, a contour-aware neural network is respectively built to enhance the coherence and the localization accuracy of semantic regions. By formulating the contour information and coarse semantic segmentation results in a unified manner, global inference is proposed to obtain the final segmentation results. Three contributions are claimed: (1) semantic segmentation via adaptive depth neural network; (2) contour-aware neural network for semantic segmentation; and (3) global inference for final decision. Experiments on three popular datasets are conducted and experimental results have verified the superiority of the proposed method compared with the state-of-the-art methods. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000425883300004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
jiang, zhiyu         L-2934-2018         
Wang, Qi                  0000-0002-7028-4956

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 204 条,共 322 条
标题: Development of an imaging gas correlation spectrometry based mid-infrared camera for two-dimensional mapping of CO in vehicle exhausts
作者: Wu, KJ (Wu, Kuijun); Feng, YT (Feng, Yutao); Yu, GB (Yu, Guangbao); Liu, LM (Liu, Linmei); Li, J (Li, Juan); Xiong, YH (Xiong, Yuanhui); Li, FQ (Li, Faquan)
来源出版物: OPTICS EXPRESS 卷: 26 期: 7 页: 8239-8251 DOI: 10.1364/OE.26.008239 出版年: APR 2 2018
摘要: Real-time imaging of CO in vehicle exhaust was demonstrated using a gas correlation spectrometry based mid-infrared camera for the first time. The novel gas-correlation imaging technique is used to eliminate the spectral interferences from background radiation and other major combustion products, and reduce the influences of the optical jitter and temperature variations, thereby identifying and quantifying the gas. We take several spectral factors into account for the instrument design, concentration calibration and data evaluation, including atmospheric transmission, radiation interference, as well as the spectral response of infrared camera, filter and gas cell. A calibration method based on the molecular spectroscopy and radiative transfer equation is developed to identify the numerical relationship between the CO concentration x length and the measured image intensity. Two-dimensional CO distribution of vehicle exhaust with a time resolution of 50 Hz and detection limit of 20 ppm x meter is achieved when the distance between optical equipment and engine nozzle is 3 m. The gas correlation spectrometry based mid-infrared camera shows a great potential as a future technique to monitor vehicle pollution emissions quantitatively and visually. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.
入藏号: WOS:000428990200034
PubMed ID: 29715793
ISSN: 1094-4087
________________________________________
第 205 条,共 322 条
标题: Two-dimensional electron gas characteristics of InP-based high electron mobility transistor terahertz detector
作者: Li, JL (Li, Jin-Lun); Cui, SH (Cui, Shao-Hui); Xu, JX (Xu, Jian-Xing); Cui, XR (Cui, Xiao-Ran); Guo, CY (Guo, Chun-Yan); Ma, B (Ma, Ben); Ni, HQ (Ni, Hai-Qiao); Niu, ZC (Niu, Zhi-Chuan)
来源出版物: CHINESE PHYSICS B 卷: 27 期: 4 文献号: 047101 DOI: 10.1088/1674-1056/27/4/047101 出版年: APR 2018
摘要: The samples of InxGa1-xAs/In0.52Al0.48As two-dimensional electron gas (2DEG) are grown by molecular beam epitaxy (MBE). In the sample preparation process, the In content and spacer layer thickness are changed and two kinds of methods, i.e., contrast body doping and delta-doping are used. The samples are analyzed by the Hall measurements at 300 K and 77 K. The InxGa1-xAs/In0.52Al0.48As 2DEG channel structures with mobilities as high as 10289 cm(2)/V.s (300 K) and 42040 cm(2)/V.s (77 K) are obtained, and the values of carrier concentration (N-c) are 3.465 x 10(12)/cm(2) and 2.502 x 10(12)/cm(2), respectively. The THz response rates of InP-based high electron mobility transistor (HEMT) structures with different gate lengths at 300 K and 77 K temperatures are calculated based on the shallow water wave instability theory. The results provide a reference for the research and preparation of InP-based HEMT THz detectors.
入藏号: WOS:000430619200001
ISSN: 1674-1056
eISSN: 1741-4199
________________________________________
第 206 条,共 322 条
标题: Theoretical Modeling of 4.3 mu m Mid-Infrared Lasing in Dy3+-Doped Chalcogenide Fiber Lasers
作者: Xiao, XS (Xiao, Xusheng); Xu, YT (Xu, Yantao); Guo, HT (Guo, Haitao); Wang, PF (Wang, Pengfei); Cui, XX (Cui, Xiaoxia); Lu, M (Lu, Min); Wang, YS (Wang, Yishan); Peng, B (Peng, Bo)
来源出版物: IEEE PHOTONICS JOURNAL 卷: 10 期: 2 文献号: 1501011 DOI: 10.1109/JPHOT.2018.2803155 出版年: APR 2018
摘要: We theoretically investigate a Dy3+-doped chalcogenide fiber lasers operating at 4.3 mu m based on the rate equations and propagation equations. The two main pump bands for 1319 and 1707 nm corresponding to the H-6(15/2)-> H-6(9/2) and H-6(15/2)-> H-6(13/2) transitions are discussed in detail. The predicted maximum slope efficiencies are determined to be similar to 7.8% and similar to 15.1% for the two pumping wavelength, respectively. Besides, the variety of laser performance has been systematically analyzed when the pump configurations, fiber length, fiber loss are varied. This numerical analysis might be useful to explore the 4.3 mu m lasing operation for the mid-infrared chalcogenide fiber lasers in future.
入藏号: WOS:000426343500001
ISSN: 1943-0655
eISSN: 1943-0647
________________________________________
第 207 条,共 322 条
标题: Fully Automatic Three-Dimensional Ultrasound Imaging Based on Conventional B-Scan
作者: Huang, QH (Huang, Qinghua); Wu, BW (Wu, Bowen); Lan, JL (Lan, Jiulong); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 卷: 12 期: 2 页: 426-436 DOI: 10.1109/TBCAS.2017.2782815 出版年: APR 2018
摘要: Robotic ultrasound systems have turned into clinical use over the past few decades, increasing precision and quality of medical operations. In this paper, we propose a fully automatic scanning system for three-dimensional (3-D) ultrasound imaging. A depth camera was first used to obtain the depth data and color data of the tissue surface. Based on the depth image, the 3-D contour of the tissue was rendered and the scan path of ultrasound probe was automatically planned. Following the scan path, a 3-D translating device drove the probe to move on the tissue surface. Simultaneously, the B-scans and their positional information were recorded for subsequent volume reconstruction. In order to stop the scanning process when the pressure on the skin exceeded a preset threshold, two force sensors were attached to the front side of the probe for forcemeasurement. In vitro and in vivo experiments were conducted for assessing the performance of the proposed system. Quantitative results show that the error of volume measurement was less than 1%, indicating that the system is capable of automatic ultrasound scanning and 3-D imaging. It is expected that the proposed system can be well used in clinical practices.
入藏号: WOS:000428547600015
PubMed ID: 29570068
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1932-4545
eISSN: 1940-9990
________________________________________
第 208 条,共 322 条
标题: Exploring Models and Data for Remote Sensing Image Caption Generation
作者: Lu, XX (Lu, Xiaoqiang); Wang, BQ (Wang, Binqiang); Zheng, XT (Zheng, Xiangtao); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 卷: 56 期: 4 页: 2183-2195 DOI: 10.1109/TGRS.2017.2776321 出版年: APR 2018
摘要: Inspired by recent development of artificial satellite, remote sensing images have attracted extensive attention. Recently, notable progress has been made in scene classification and target detection. However, it is still not clear how to describe the remote sensing image content with accurate and concise sentences. In this paper, we investigate to describe the remote sensing images with accurate and flexible sentences. First, some annotated instructions are presented to better describe the remote sensing images considering the special characteristics of remote sensing images. Second, in order to exhaustively exploit the contents of remote sensing images, a large-scale aerial image data set is constructed for remote sensing image caption. Finally, a comprehensive review is presented on the proposed data set to fully advance the task of remote sensing caption. Extensive experiments on the proposed data set demonstrate that the content of the remote sensing image can be completely described by generating language descriptions. The data set is available at https://github.com/201528014227051/RSICD_optimal.
入藏号: WOS:000428673800025
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Wang, Binqiang                  0000-0001-9406-167X
Li, Xuelong                  0000-0002-0019-4197
Zheng, Xiangtao                  0000-0002-8398-6324

ISSN: 0196-2892
eISSN: 1558-0644
________________________________________
第 209 条,共 322 条
标题: 2.5-D Extended Field-of-View Ultrasound
作者: Huang, QH (Huang, Qinghua); Zeng, Z (Zeng, Zhaozheng); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON MEDICAL IMAGING 卷: 37 期: 4 页: 851-859 DOI: 10.1109/TMI.2017.2776971 出版年: APR 2018
摘要: Recently, the growing emphasis on medical ultrasound (US) has led to a rapid development of US extended field-of-view (EFOV) techniques. US EFOV techniques can be classified into three categories: 2-D US EFOV, 3-D US, and 3-D US EFOV. In this paper, we propose a novel EFOV method called 2.5-D US EFOV that combines both the advantages of the 2-D US EFOV and the 3-D US by generating a panorama on a curved image plane guided by a curved scanning trajectory of the US probe. In 2.5-D US EFOV, the real-time position and orientation of the US image plane can be recorded via an electromagnetic spatial sensor attached to the probe. The scanning direction is not necessarily straight and can be curved according to the regions of interest (ROI). To form the curved panorama, an image cutting method is proposed. Finally, the curved panorama is rendered in a 3-D space using a surface rendering based on a texture mapping technique. This allows 3-D measurements of lines and angles. Phantom experiments demonstrated that 2.5-DUS EFOV images could show anatomical structures of ROI accurately and rapidly. The overall average errors for the distance and angle measurements are -0.097 +/- 0.128 cm (-1% +/- 1.2%) and 1.50 degrees +/- 1.60 degrees (1.9% +/- 2%), respectively. A typical extended US image can be reconstructed from 321 B-scans images within 3 s. The satisfying quantitative result on the spinal tissues of a scoliosis subject demonstrates that our system has potential applications in the assessment of musculoskeletal issues.
入藏号: WOS:000428886700003
PubMed ID: 29610066
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0278-0062
eISSN: 1558-254X
________________________________________
第 210 条,共 322 条
标题: Feature Combination via Clustering
作者: Hou, J (Hou, Jian); Gao, HJ (Gao, Huijun); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 4 页: 896-907 DOI: 10.1109/TNNLS.2016.2645883 出版年: APR 2018
摘要: In image classification, feature combination is often used to combine the merits of multiple complementary features and improve the classification accuracy compared with one single feature. Existing feature combination algorithms, e.g., multiple kernel learning, usually determine the weights of features based on the optimization with respect to some classifier-dependent objective function. These algorithms are often computationally expensive, and in some cases are found to perform no better than simple baselines. In this paper, we solve the feature combination problem from a totally different perspective. Our algorithm is based on the simple idea of combining only base kernels suitable to be combined. Since the very aim of feature combination is to obtain the highest possible classification accuracy, we measure the combination suitableness of two base kernels by the maximum possible cross-validation accuracy of their combined kernel. By regarding the pairwise suitableness as the kernel adjacency, we obtain a weighted graph of all base kernels and find that the base kernels suitable to be combined correspond to a cluster in the graph. We then use the dominant sets algorithm to find the cluster and determine the weights of base kernels automatically. In this way, we transform the kernel combination problem into a clustering one. Our algorithm can be implemented in parallel easily and the running time can be adjusted based on available memory to a large extent. In experiments on several data sets, our algorithm generates comparable classification accuracy with the state of the art.
入藏号: WOS:000427859600011
PubMed ID: 28141531
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 211 条,共 322 条
标题: Regularized Label Relaxation Linear Regression
作者: Fang, XZ (Fang, Xiaozhao); Xu, Y (Xu, Yong); Li, XL (Li, Xuelong); Lai, ZH (Lai, Zhihui); Wong, WK (Wong, Wai Keung); Fang, BW (Fang, Bingwu)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 4 页: 1006-1018 DOI: 10.1109/TNNLS.2017.2648880 出版年: APR 2018
摘要: Linear regression (LR) and some of its variants have been widely used for classification problems. Most of these methods assume that during the learning phase, the training samples can be exactly transformed into a strict binary label matrix, which has too little freedom to fit the labels adequately. To address this problem, in this paper, we propose a novel regularized label relaxation LR method, which has the following notable characteristics. First, the proposed method relaxes the strict binary label matrix into a slack variable matrix by introducing a nonnegative label relaxation matrix into LR, which provides more freedom to fit the labels and simultaneously enlarges the margins between different classes as much as possible. Second, the proposed method constructs the class compactness graph based on manifold learning and uses it as the regularization item to avoid the problem of overfitting. The class compactness graph is used to ensure that the samples sharing the same labels can be kept close after they are transformed. Two different algorithms, which are, respectively, based on l(2)-norm and l(2,1)-norm loss functions are devised. These two algorithms have compact closed-form solutions in each iteration so that they are easily implemented. Extensive experiments show that these two algorithms outperform the state-of-the-art algorithms in terms of the classification accuracy and running time.
入藏号: WOS:000427859600020
PubMed ID: 28166507
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Lai, Zhihui         R-1000-2019         0000-0002-4388-3080
Li, Xuelong         Z-3785-2019         
Wong, Wai Keung                  0000-0002-5214-7114
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 212 条,共 322 条
标题: Person Reidentification Based on Elastic Projections
作者: Li, XL (Li, Xuelong); Liu, LN (Liu, Lina); Lu, XQ (Lu, Xiaoqiang)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 4 页: 1314-1327 DOI: 10.1109/TNNLS.2016.2602855 出版年: APR 2018
摘要: Person reidentification usually refers to matching people in different camera views in nonoverlapping multicamera networks. Many existing methods learn a similarity measure by projecting the raw feature to a latent subspace to make the same target's distance smaller than different targets' distances. However, the same targets captured in different camera views should hold the same intrinsic attributes while different targets should hold different intrinsic attributes. Projecting all the data to the same subspace would cause loss of such an information and comparably poor discriminability. To address this problem, in this paper, a method based on elastic projections is proposed to learn a pairwise similarity measure for person reidentification. The proposed model learns two projections, positive projection and negative projection, which are both representative and discriminative. The representability refers to: for the same targets captured in two camera views, the positive projection can bridge the corresponding appearance variation and represent the intrinsic attributes of the same targets, while for the different targets captured in two camera views, the negative projection can explore and utilize the different attributes of different targets. The discriminability means that the intraclass distance should become smaller than its original distance after projection, while the interclass distance becomes larger on the contrary, which is the elastic property of the proposed model. In this case, prior information of the original data space is used to give guidance for the learning phase; more importantly, similar targets (but not the same) are effectively reduced by forcing the same targets to become more similar and different targets to become more distinct. The proposed model is evaluated on three benchmark data sets, including VIPeR, GRID, and CUHK, and achieves better performance than other methods.
入藏号: WOS:000427859600044
PubMed ID: 28422688
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 213 条,共 322 条
标题: A yttrium aluminosilicate glass fiber with graded refractive index fabricated by melt-in-tube method
作者: Zhang, YM (Zhang, Yeming); Qian, GQ (Qian, Guoquan); Xiao, XS (Xiao, Xusheng); Tian, XL (Tian, Xiangling); Chen, Z (Chen, Zhi); Zhong, JP (Zhong, Jiuping); Ma, ZJ (Ma, Zhijun); Guo, HT (Guo, Haitao); Xu, SH (Xu, Shanhui); Yang, ZM (Yang, Zhongmin); Qiu, JR (Qiu, Jianrong)
来源出版物: JOURNAL OF THE AMERICAN CERAMIC SOCIETY 卷: 101 期: 4 页: 1616-1622 DOI: 10.1111/jace.15320 出版年: APR 2018
摘要: A graded-index fiber with yttrium aluminosilicate (YAS) glass core was fabricated by a Melt-in-Tube method. The refractive index and stress profiles of the fibers exhibit a highly symmetrical gradient tendency along the radial axis which is in accordance with the results of element migration. Based on the formation mechanism of YAS glass core, the relationships between the refractive index/stress profile and the spontaneous migration are discussed. A linear all-fiber laser based on the obtained fiber shows a laser output threshold of 11.48 mW and slope efficiency of 8.3%. The near-field beam intensity distribution of fiber laser with spectrum FWHM of 0.24 nm indicates the good laser beam quality. The facile Melt-in-tube method was proved to be reliable in designing graded-index fiber through the dissolution and diffusion process, which is more advanced than commonly used Rod-in-tube method.
入藏号: WOS:000424095000025
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Tian, Xiangling         M-3751-2018         0000-0002-8141-5720

ISSN: 0002-7820
eISSN: 1551-2916
________________________________________
第 214 条,共 322 条
标题: A compact large-format streak tube for imaging lidar
作者: Hui, DD (Hui, Dandan); Luo, D (Luo, Duan); Tian, LP (Tian, Liping); Lu, Y (Lu, Yu); Chen, P (Chen, Ping); Wang, JF (Wang, Junfeng); Sai, XF (Sai, Xiaofeng); Wen, WL (Wen, Wenlong); Wang, X (Wang, Xing); Xin, LW (Xin, Liwei); Zhao, W (Zhao, Wei); Tian, JS (Tian, Jinshou)
来源出版物: REVIEW OF SCIENTIFIC INSTRUMENTS 卷: 89 期: 4 文献号: 045113 DOI: 10.1063/1.5024269 出版年: APR 2018
摘要: The streak tubes with a large effective photocathode area, large effective phosphor screen area, and high photocathode radiant sensitivity are essential for improving the field of view, depth of field, and detectable range of the multiple-slit streak tube imaging lidar. In this paper, a high spatial resolution, large photocathode area, and compact meshless streak tube with a spherically curved cathode and screen is designed and tested. Its spatial resolution reaches 20 lp/mm over the entire Phi 28 mm photocathode working area, and the simulated physical temporal resolution is better than 30 ps. The temporal distortion in our large-format streak tube, which is shown to be a non-negligible factor, has a minimum value as the radius of curvature of the photocathode varies. Furthermore, the photocathode radiant sensitivity and radiant power gain reach 41 mA/W and 18.4 at the wavelength of 550 nm, respectively. Most importantly, the external dimensions of our streak tube are no more than Phi 60 mm x 110 mm. Published by AIP Publishing.
入藏号: WOS:000431139400070
PubMed ID: 29716329
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Luo, Duan                  0000-0001-5926-9870

ISSN: 0034-6748
eISSN: 1089-7623
________________________________________
第 215 条,共 322 条
标题: Seeker-Azimuth Determination with Gyro Rotor and Optoelectronic Sensors
作者: Bai, JM (Bai, Jian-Ming); Zhao, GS (Zhao, Guangshe); Rong, HJ (Rong, Hai-Jun); Wang, XH (Wang, Xianhua)
来源出版物: SENSORS 卷: 18 期: 4 文献号: 1256 DOI: 10.3390/s18041256 出版年: APR 2018
摘要: This paper presents an approach to seeker-azimuth determination using the gyro rotor and optoelectronic sensors. In the proposed method, the gyro rotor is designed with a set of black and white right spherical triangle patterns on its surface. Two pairs of optoelectronic sensors are located symmetrically around the gyro rotor. When there is an azimuth, the stripe width covering the black and white patterns changes. The optoelectronic sensors then capture the reflected optical signals from the different black and white pattern stripes on the gyro rotor and produce the duty ratio signal. The functional relationship between the measured duty ratio and the azimuth information is numerically derived, and, based on this relationship, the azimuth is determined from the measured duty ratio. Experimental results show that the proposed approach produces a large azimuth range and high measurement accuracy with the linearity error of less than 0.005.
入藏号: WOS:000435574800328
PubMed ID: 29671757
ISSN: 1424-8220
________________________________________
第 216 条,共 322 条
标题: Optical Planar Waveguides Fabricated by Using Carbon Ion Implantation in Terbium Gallium Garnet
作者: Wang, Y (Wang, Yue); Shen, XL (Shen, Xiao-Liang); Zheng, RL (Zheng, Rui-Lin); Lv, P (Lv, Peng); Liu, CX (Liu, Chun-Xiao); Guo, HT (Guo, Hai-Tao)
来源出版物: JOURNAL OF THE KOREAN PHYSICAL SOCIETY 卷: 72 期: 7 页: 765-769 DOI: 10.3938/jkps.72.765 出版年: APR 2018
摘要: Optical planar waveguides in terbium-gallium-garnet (TGG) crystals are promising photonic devices, particularly for optical isolators and rotators. In this work, to the best of our knowledge, we report on the fabrication and the characterization of TGG waveguides for the first time. The fabrication procedure involved carbon ion implantation at an energy of 6.0 MeV and a fluence of 5.0x10(14) ions/cm(2). The effective refractive indices of the propagation modes in the carbonimplanted waveguide were measured by using the prism-coupling technique. The profile of the refractive index and the distribution of the near-field intensity were calculated by using the reflectivity calculation method and the finite-difference beam propagation method, respectively. The carbon-implanted TGG waveguide is considered to be a candidate for a magneto-optical photonic device.
入藏号: WOS:000429586000004
ISSN: 0374-4884
eISSN: 1976-8524
________________________________________
第 217 条,共 322 条
标题: Complementary Normalized Compressive Ghost Imaging With Entangled Photons
作者: Liu, DW (Liu, Dawei); Li, LF (Li, Lifei); Chen, H (Chen, Hui); Kang, Y (Kang, Yan); Zhang, TY (Zhang, Tongyi); Zhao, W (Zhao, Wei); Dong, WB (Dong, Weibin); Shi, KL (Shi, Kunlin)
来源出版物: IEEE PHOTONICS JOURNAL 卷: 10 期: 2 文献号: 7500507 DOI: 10.1109/JPHOT.2018.2813974 出版年: APR 2018
摘要: We demonstrate a compressive normalized ghost imaging system with entangled photons employing complementary compressive imaging (CCI) technique. The quantum ghost image reconstruction was achieved with 19.53% sampling ratio of raster scanning and average 0.78 photons/pixel of each measurement. Using the special +1/-1 type sensing matrix and appropriate optimal algorithm, the photon utilization efficiency, and robustness of the imaging system is enhanced significantly. Our results reveal the great potential of CCI technique applied in quantum imaging and other quantum optics field such as quantum characterizing and quantum state tomography to use the information loaded in each photon with high efficiency.
入藏号: WOS:000429073700001
ISSN: 1943-0655
eISSN: 1943-0647
________________________________________
第 218 条,共 322 条
标题: Plasmonic Fano spectral response from graphene metasurfaces in the MIR region
作者: Lu, H (Lu, Hua); Mao, D (Mao, Dong); Zeng, C (Zeng, Chao); Xiao, FJ (Xiao, Fajun); Yang, DX (Yang, Dexing); Mei, T (Mei, Ting); Zhao, JL (Zhao, Jianlin)
来源出版物: OPTICAL MATERIALS EXPRESS 卷: 8 期: 4 页: 1058-1068 DOI: 10.1364/OME.8.001058 出版年: APR 1 2018
摘要: We present a controlled Fano resonance in the mid-infrared (MIR) region from a kind of plasmonic metasurface consisting of a single-atom-thick surface layer with a periodic pattern of graphene nanostrip pairs on a dielectric substrate. Both the numerical and theoretical results indicate that the Fano resonance spectrum can be flexibly tailored through adjusting the geometrical parameters, such as the asymmetric distance and coupling gap between each pair of graphene nanostrips. Particularly, we achieve the dynamic tunability of the plasmonic Fano resonance spectrum by controlling the polarization of incident light and the Fermi level of graphene. The theoretical calculations agree well with the numerical simulations. These results could find significant applications in nanoscale light control and functional devices operating in the MIR region. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement.
入藏号: WOS:000428955700035
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Mao, 8731629         G-5113-2014         0000-0002-5744-6316
Lu, Hua         G-3042-2014         
Xiao, Fajun                  0000-0002-7656-7869

ISSN: 2159-3930
________________________________________
第 219 条,共 322 条
标题: High-performance transverse magnetic mode-pass polarizer based on silicon nitride-silicon subwavelength grating waveguide for mid-infrared wavelengths
作者: Chi, J (Chi, Jiao); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu)
来源出版物: APPLIED PHYSICS EXPRESS 卷: 11 期: 4 文献号: 042005 DOI: 10.7567/APEX.11.042005 出版年: APR 2018
摘要: A high-performance transverse-magnetic (TM) mode-pass polarizer for mid-infrared wavelengths based on a silicon nitride-silicon subwavelength grating (SWG) waveguide is proposed. The designed device supports the Bloch mode for the TM mode only, whereas the transverse-electric mode is reflected by the SWG. Simulations show that with a device length of 7 mu m, this polarizer is capable of achieving an ultrahigh polarization extinction ratio PER) of similar to 50 dB and an insertion loss of similar to 0.3 dB at a wavelength of 2 mu m. The device bandwidth is increased to 60nm for PER > 30 dB. The polarizer also shows good tolerance to fabrication uncertainties. (c) 2018 The Japan Society of Applied Physics
入藏号: WOS:000428772000001
ISSN: 1882-0778
eISSN: 1882-0786
________________________________________
第 220 条,共 322 条
标题: Influences of multiphoton absorption and free-carrier effects on frequency-comb generation in normal dispersion silicon microresonators
作者: Liu, ML (Liu, Mulong); Wang, LR (Wang, Leiran); Sun, QB (Sun, Qibing); Li, SQ (Li, Siqi); Ge, ZQ (Ge, Zhiqiang); Lu, ZZ (Lu, Zhizhou); Wang, WQ (Wang, Weiqiang); Wang, GX (Wang, Guoxi); Zhang, WF (Zhang, Wenfu); Hu, XH (Hu, Xiaohong); Zhao, W (Zhao, Wei)
来源出版物: PHOTONICS RESEARCH 卷: 6 期: 4 页: 238-243 DOI: 10.1364/PRJ.6.000238 出版年: APR 1 2018
摘要: We investigate frequency-comb generation in normal dispersion silicon microresonators from the near-infrared to mid-infrared wavelength range in the presence of multiphoton absorption and free-carrier effects. It is found that parametric oscillation is inhibited in the telecom wavelength range resulting from strong two-photon absorption. On the contrary, beyond the wavelength of 2200 nm, where three-and four-photon absorption are less detrimental, a comb can be generated with moderate pump power, or free-carriers are swept out by a positive-intrinsic-negative structure. In the temporal domain, the generated combs correspond to flat-top pulses, and the pulse duration can be easily controlled by varying the laser detuning. The reported comb generation process shows a high conversion efficiency compared with anomalous dispersion regime, which can guide and promote comb formation in materials with normal dispersion. As the comb spectra cover the mid-infrared wavelength range, they can find applications in comb-based radiofrequency photonic filters and mid-infrared spectroscopy. (c) 2018 Chinese Laser Press
入藏号: WOS:000428961400007
ISSN: 2327-9125
________________________________________
第 221 条,共 322 条
标题: Studying Properties of Composite Nano-PAA-Au Array for the Optimal SERS Sensitivity
作者: Sui, CF (Sui, Chaofan); Zhao, WX (Zhao, Wenxuan); Wang, KG (Wang, Kaige); Ba, HQ (Ba, Hanqing); Wang, S (Wang, Shuang); Bai, XH (Bai, Xiaohong); Bai, JT (Bai, Jintao)
来源出版物: PLASMONICS 卷: 13 期: 2 页: 631-638 DOI: 10.1007/s11468-017-0554-9 出版年: APR 2018
摘要: The composite structure of nano-porous anodic alumina (nano-PAA) coated with noble metal layer has been demonstrated to be one kind of high-sensitive surface-enhanced Raman scattering (SERS)-active substrate. However, the experimental investigations on influences of parameters were restricted by correlation between variables. And in relevant simulation studies, nano-tips at intersections of unit edges on the surface and the metal attaching to inside walls of nano-holes which are crucial for the enhancement of electric field were commonly idealized. To obtain the optimal structure of nano-PAA-Au array for SERS applications, numerical evaluations of the electric field distributions and intensities at hotspots were carried out on a proposed precise model. The influence of structure and excitation parameters which determined the electromagnetic enhancement have been systematically investigated. The numerical data shows that the intensity and distribution of surface electric field is evidently affected by both the characteristics of nano-tips and the metal attaching to the inside wall of holes. In addition, the designed substrate was synthesized accordingly and demonstrated to be higher sensitive with an achieved enhancement factor of 1.04 x 10(7). The study would be helpful in designing high-sensitive SERS-active substrates.
入藏号: WOS:000428074500034
ISSN: 1557-1955
eISSN: 1557-1963
________________________________________
第 222 条,共 322 条
标题: Fabrication of planar optical waveguides by 6.0MeV silicon ion implantation in Nd-doped phosphate glasses
作者: Shen, XL (Shen, Xiao-Liang); Dai, HQ (Dai, Han-Qing); Zhang, LL (Zhang, Liao-Lin); Wang, Y (Wang, Yue); Zhu, QF (Zhu, Qi-Feng); Guo, HT (Guo, Hai-Tao); Li, WN (Li, Wei-Nan); Liu, CX (Liu, Chun-Xiao)
来源出版物: JAPANESE JOURNAL OF APPLIED PHYSICS 卷: 57 期: 4 文献号: 042204 DOI: 10.7567/JJAP.57.042204 出版年: APR 2018
摘要: We report the fabrication of a planar optical waveguide by silicon ion implantation into Nd-doped phosphate glass at an energy of 6.0MeV and a dose of 5.0 x 10(14) ions/cm(2). The change in the surface morphology of the glass after the implantation can be clearly observed by scanning electron microscopy. The measurement of the dark mode spectrum of the waveguide is conducted using a prism coupler at 632.8 nm. The refractive index distribution of the waveguide is reconstructed by the reflectivity calculation method. The near-field optical intensity profile of the waveguide is measured using an end-face coupling system. The waveguide with good optical properties on the glass matrix may be valuable for the application of the Nd-doped phosphate glass in integrated optical devices. (c) 2018 The Japan Society of Applied Physics
入藏号: WOS:000427386600001
ISSN: 0021-4922
eISSN: 1347-4065
________________________________________
第 223 条,共 322 条
标题: An optical method for characterizing domain wall motions and ferroelectric hysteresis in tetragonal Mn:Fe:KTN co-doped crystals
作者: Lu, QN (Lu, Qieni); Li, BH (Li, Bihua); Li, Z (Li, Zhen); Dai, HT (Dai, Haitao); Liao, YS (Liao, Yushan)
来源出版物: JOURNAL OF MATERIALS SCIENCE 卷: 53 期: 8 特刊: SI 页: 5987-5996 DOI: 10.1007/s10853-017-1981-x 出版年: APR 2018
摘要: An optical method is proposed to extract the displacement vector of domain wall (DW) sidewise motion from ferroelectric domain configuration pattern on a tetragonal Mn:Fe:KTN crystal. The ferroelectric domain configuration evolution under an external electric field is observed in situ using optical microscope imaging system, and the relative displacement of DW sideways motion between two adjacent electric fields is extracted. By the combination of the new domain length vector extracted, the ferroelectric domain displacement vector as a function of field strength can be obtained; what is more, the hysteresis loop can be achieved during field cycling. The method provides an access to directly manipulating DW motion and exploring the properties of ferroelectric materials from ferroelectric domain configuration pattern.
入藏号: WOS:000423711900029
ISSN: 0022-2461
eISSN: 1573-4803
________________________________________
第 224 条,共 322 条
标题: Learning binary codes with local and inner data structure
作者: He, SY (He, Shiyuan); Ye, G (Ye, Guo); Hu, MQ (Hu, Mengqiu); Yang, Y (Yang, Yang); Shen, FM (Shen, Fumin); Shen, HT (Shen, Heng Tao); Li, XL (Li, Xuelong)
来源出版物: NEUROCOMPUTING 卷: 282 页: 32-41 DOI: 10.1016/j.neucom.2017.12.005 出版年: MAR 22 2018
摘要: Recent years have witnessed the promising capacity of hashing techniques in tackling nearest neighbor search because of the high efficiency in storage and retrieval. Data-independent approaches (e.g., Locality Sensitive Hashing) normally construct hash functions using random projections, which neglect intrinsic data properties. To compensate this drawback, learning-based approaches propose to explore local data structure and/or supervised information for boosting hashing performance. However, due to the construction of Laplacian matrix, existing methods usually suffer from the unaffordable training cost. In this paper, we propose a novel supervised hashing scheme, which has the merits of (1) exploring the inherent neighborhoods of samples; (2) significantly saving training cost confronted with massive training data by employing approximate anchor graph; as well as (3) preserving semantic similarity by leveraging pair-wise supervised knowledge. Besides, we integrate discrete constraint to significantly eliminate accumulated errors in learning reliable hash codes and hash functions. We devise an alternative algorithm to efficiently solve the optimization problem. Extensive experiments on various image datasets demonstrate that our proposed method is superior to the state-of-the-arts. (c) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000424893200004
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 225 条,共 322 条
标题: Broadband pulsed difference frequency generation laser source centered 3326 nm based on ring fiber lasers
作者: Chen, GW (Chen, Guangwei); Li, WL (Li, Wenlei)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 8 文献号: 1850090 DOI: 10.1142/S0217984918500902 出版年: MAR 20 2018
摘要: A broadband pulsed mid-infrared difference frequency generation (DFG) laser source based on MgO-doped congruent LiNbO3 bulk is experimentally demonstrated, which employs a homemade pulsed ytterbium-doped ring fiber laser and a continuous wave erbium-doped ring fiber laser to act as seed sources. The experimental results indicate that the perfect phase match crystal temperature is about 74.5 degrees C. The maximum spectrum bandwidth of idler is about 60 nm with suitable polarization states of fundamental lights. The central wavelength of idlers varies from 3293 nm to 3333 nm over the crystal temperature ranges of 70.4-76 degrees C. A jump of central wavelength exists around crystal temperature of 72 degrees C with variation of about 30 nm. The conversion efficiency of DFG can be tuned with the crystal temperature and polarization states of fundamental lights.
入藏号: WOS:000427255700010
ISSN: 0217-9849
eISSN: 1793-6640
________________________________________
第 226 条,共 322 条
标题: Dielectrophoresis-actuated in-plane optofluidic lens with tunability of focal length from negative to positive
作者: Chen, QM (Chen, Qingming); Li, TH (Li, Tenghao); Zhu, YJ (Zhu, Yujiao); Yu, WX (Yu, Weixing); Zhang, XM (Zhang, Xuming)
来源出版物: OPTICS EXPRESS 卷: 26 期: 6 页: 6532-6541 DOI: 10.1364/OE.26.006532 出版年: MAR 19 2018
摘要: This paper reports a tunable in-plane optofluidic lens by continuously tuning a silicone oil-air interface from concave to convex using the dielectrophoresis (DEP) force. Two parallel glasses are bonded firmly on two sides by NOA 81(Norland Optical Adhesive 81) spacers, forming an open microfluidic channel. An ITO (indium tin oxide) strip and another unpatterned ITO layer are deposited on two glasses as the top and bottom electrodes. Initially, a capillary concave liquid-air interface is formed at the end of the open channel. Then the DEP force is enabled to continuously deform the interface (lens) from concave to convex. In the experiment, the focal length gradually decreases from about -1 mm to infinite and then from infinite to around + 1 mm when the driving voltage is increased from 0 V to 260 V. Particularly, the longitudinal spherical aberration (LSA) is effectively suppressed to have LSA < 0.04 when the lens is operated in the focusing state. This work is the first study of in-plane tunable lenses using the DEP force and possesses special merits as compared to the other reported tunable lenses that are formed by pumping different liquids or by temperature gradient, such as wide tunability, no need for continuous supply of liquids, low power consumption (similar to 81 nJ per switching) due to the capacitor-type driving, and the use of only one type of liquid. Besides, its low aberration makes it favorable for light manipulation in microfluidic networks. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000427900400019
PubMed ID: 29609341
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Weixing         G-3658-2012         0000-0002-3216-526X
Zhang, Xuming         K-4900-2013         0000-0002-9326-5547

ISSN: 1094-4087
________________________________________
第 227 条,共 322 条
标题: Optical amplification of Airy beams by photorefractive two-wave mixing
作者: Yang, X (Yang, Xu); Wang, MR (Wang, Meirong); Lou, CB (Lou, Cibo); Zhang, P (Zhang, Peng)
来源出版物: OPTICS EXPRESS 卷: 26 期: 6 页: 7281-7287 DOI: 10.1364/OE.26.007281 出版年: MAR 19 2018
摘要: We propose and demonstrate nonlinear amplifications of self-accelerating Airy beams by two-wave mixing in photorefractive crystals both numerically and experimentally. By employing a broad Gaussian beam as the pump beam, we show that weak signal Airy beams can be significantly amplified under both diffusion and drift mechanisms. It is revealed that not only higher optical gains but also faster response time can be achieved in the presence of an external electric field, where the drift mechanism dominates. We verify that the self-accelerating and self-healing characteristics of the Airy beams are well preserved during the nonlinear amplification. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000427900400086
PubMed ID: 29609414
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Jingjun, Xu         A-1282-2010         

ISSN: 1094-4087
________________________________________
第 228 条,共 322 条
标题: Compact orthogonal-dispersion device using a prism and a transmission grating
作者: Yang, QH (Yang, Qinghua); Wang, WQ (Wang, Weiqiang)
来源出版物: JOURNAL OF THE EUROPEAN OPTICAL SOCIETY-RAPID PUBLICATIONS 卷: 14 文献号: 8 DOI: 10.1186/s41476-018-0077-9 出版年: MAR 12 2018
摘要: Background: Spectroscopy was one of the main applications of gratings. Most spectrometers today are based on reflection grating designs, since high quality transmission grating technologies have only matured over the last several years. Conventional cross-dispersion systems are based on the reflection grating. For traditional direct-vision or constant-dispersion grism, both the prism and grating have the same dispersion direction.
Methods: This paper presents an orthogonal-dispersion device based on a transmission grating attached to a prism. The dispersion directions of the prism and transmission grating are orthogonal. The analytical expressions for the dispersion of this device are derived in detail. The numerical results and ray-tracing simulations by ZEMAX software are shown.
Results: The simulation results show that the spectrum is spread over 5 diffraction orders, m=3 to -1, the non-diffracted order m=0 is straight, and the other orders are curved.
Conclusions: The device will be able to provide a compact, small-sized and broadband orthogonal-dispersion device that is suitable for the medium resolution spectrometer.
入藏号: WOS:000428316100001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yang, Qinghua                  0000-0003-4679-1621

ISSN: 1990-2573
________________________________________
第 229 条,共 322 条
标题: Electrically tunable robust edge states in graphene-based topological photonic crystal slabs
作者: Song, ZD (Song, Zidong); Liu, HJ (Liu, HongJun); Huang, N (Huang, Nan); Wang, ZL (Wang, ZhaoLu)
来源出版物: JOURNAL OF PHYSICS D-APPLIED PHYSICS 卷: 51 期: 9 文献号: 095108 DOI: 10.1088/1361-6463/aaa9fe 出版年: MAR 7 2018
摘要: Topological photonic crystals are optical structures supporting topologically protected unidirectional edge states that exhibit robustness against defects. Here, we propose a graphene-based all-dielectric photonic crystal slab structure that supports two-dimensionally confined topological edge states. These topological edge states can be confined in the out-of-plane direction by two parallel graphene sheets. In the structure, the excitation frequency range of topological edge states can be dynamically and continuously tuned by varying bias voltage across the two parallel graphene sheets. Utilizing this kind of architecture, we construct Z-shaped channels to realize topological edge transmission with diffrerent frequencies. The proposal provides a new degree of freedom to dynamically control topological edge states and potential applications for robust integrated photonic devices and optical communication systems.
入藏号: WOS:000425118800001
ISSN: 0022-3727
eISSN: 1361-6463
________________________________________
第 230 条,共 322 条
标题: A case-oriented web-based training system for breast cancer diagnosis
作者: Huang, QH (Huang, Qinghua); Huang, XH (Huang, Xianhai); Liu, LZ (Liu, Longzhong); Lin, YD (Lin, Yidi); Long, XZ (Long, Xingzhang); Li, XL (Li, Xuelong)
来源出版物: COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 卷: 156 页: 73-83 DOI: 10.1016/j.cmpb.2017.12.028 出版年: MAR 2018
摘要: Background and Objective: Breast cancer is still considered as the most common form of cancer as well as the leading causes of cancer deaths among women all over the world. We aim to provide a web-based breast ultrasound database for online training inexperienced radiologists and giving computer-assisted diagnostic information for detection and classification of the breast tumor.& para;& para;Methods: We introduce a web database which stores breast ultrasound images from breast cancer patients as well as their diagnostic information. A web-based training system using a feature scoring scheme based on Breast Imaging Reporting and Data System (BI-RADS) US lexicon was designed. A computer-aided diagnosis (CAD) subsystem was developed to assist the radiologists to make scores on the BI-RADS features for an input case. The training system possesses 1669 scored cases, where 412 cases are benign and 1257 cases are malignant. It was tested by 31 users including 12 interns, 11 junior radiologists, and 8 experienced senior radiologists.& para;& para;Results: This online training system automatically creates case-based exercises to train and guide the newly employed or resident radiologists for the diagnosis of breast cancer using breast ultrasound images based on the BI-RADS. After the trainings, the interns and junior radiologists show significant improvement in the diagnosis of the breast tumor with ultrasound imaging (p-value < .05); meanwhile the senior radiologists show little improvement (p-value > .05).& para;& para;Conclusions: The online training system can improve the capabilities of early-career radiologists in distinguishing between the benign and malignant lesions and reduce the misdiagnosis of breast cancer in a quick, convenient and effective manner. (C) 2018 Elsevier B.V. All rights reserved.
入藏号: WOS:000424764800008
PubMed ID: 29428078
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong         Z-3785-2019         
Liu, Longzhong                  0000-0003-4639-1767
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0169-2607
eISSN: 1872-7565
________________________________________
第 231 条,共 322 条
标题: Graphene-Silver Hybrid Metamaterial for Tunable and High Absorption at Mid-Infrared Waveband
作者: Cao, S (Cao, Shun); Wang, TS (Wang, Taisheng); Sun, Q (Sun, Qiang); Tang, YG (Tang, Yuguo); Hu, BL (Hu, Bingliang); Levy, U (Levy, Uriel); Yu, WX (Yu, Weixing)
来源出版物: IEEE PHOTONICS TECHNOLOGY LETTERS 卷: 30 期: 5 页: 475-478 DOI: 10.1109/LPT.2018.2800729 出版年: MAR 1 2018
摘要: We proposed a hybrid metamaterial structure based on graphene-silver, which has tunable and efficient light-absorbing performance at the mid-infrared regime. It is shown that this model can absorb light effectively with a maximum of 100% at the absorption peak wavelength. In addition, the absorption peak wavelength can be adjusted flexibly by changing parameters, including the chemical potential applied to graphene or other structural parameters of the structure. This nearly perfect absorption capability is attributed to the synergetic effects of the localized surface plasmon enhancement of Ag nanoribbon, graphene plasmonics, metal-insulator-graphene mode and Fabry-Perot resonance. This kind of tunable absorber can be used in mid-infrared photodetectors or spectroscopy fields.
入藏号: WOS:000429172600012
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Cao, Shun         J-4637-2019         0000-0002-9841-2411
Yu, Weixing         G-3658-2012         0000-0002-3216-526X

ISSN: 1041-1135
eISSN: 1941-0174
________________________________________
第 232 条,共 322 条
标题: A Feedback-Based Robust Video Stabilization Method for Traffic Videos
作者: Ling, Q (Ling, Qiang); Deng, SB (Deng, Sibin); Li, F (Li, Feng); Huang, QH (Huang, Qinghua); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 卷: 28 期: 3 页: 561-572 DOI: 10.1109/TCSVT.2016.2618934 出版年: MAR 2018
摘要: Traffic videos are often recorded by vehicle-mounted cameras. Compared with videos recorded by handheld cameras, traffic videos suffer from more challenges, such as higher frequency and more violent jitters, dynamic scenes, large moving objects, and parallax, which can result in significant visual quality degradation. To address these challenges for traffic videos, we propose a special stabilization method. The key aspect of our method is a feedback strategy that divides the extracted feature trajectories into background trajectories and foreground trajectories by feeding back the previous trajectory classification results. The method can perform robustly, even in the case of large moving objects and parallax. Furthermore, our method maintains the number of available background trajectories within a reasonable range via two refinement strategies. One strategy attempts to reliably recover background trajectories from misjudged foreground trajectories when there are an insufficient number of background trajectories. The other strategy can adaptively adjust the number of feature points in each frame to efficiently avoid too many or too few background trajectories. With the obtained background trajectories, a homography matrix between each frame and its stabilized view is computed and implemented to warp the frame image to produce smooth videos. Experimental results confirm that our method is both effective in stabilizing traffic videos and quite robust against large moving objects and parallax.
入藏号: WOS:000426693100001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1051-8215
eISSN: 1558-2205
________________________________________
第 233 条,共 322 条
标题: Object Discovery via Cohesion Measurement
作者: Guo, GJ (Guo, Guanjun); Wang, HZ (Wang, Hanzi); Zhao, WL (Zhao, Wan-Lei); Yan, Y (Yan, Yan); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON CYBERNETICS 卷: 48 期: 3 页: 862-875 DOI: 10.1109/TCYB.2017.2661995 出版年: MAR 2018
摘要: Color and intensity are two important components in an image. Usually, groups of image pixels, which are similar in color or intensity, are an informative representation for an object. They are therefore particularly suitable for computer vision tasks, such as saliency detection and object proposal generation. However, image pixels, which share a similar real-world color, may be quite different since colors are often distorted by intensity. In this paper, we reinvestigate the affinity matrices originally used in image segmentation methods based on spectral clustering. A new affinity matrix, which is robust to color distortions, is formulated for object discovery. Moreover, a cohesion measurement (CM) for object regions is also derived based on the formulated affinity matrix. Based on the new CM, a novel object discovery method is proposed to discover objects latent in an image by utilizing the eigenvectors of the affinity matrix. Then we apply the proposed method to both saliency detection and object proposal generation. Experimental results on several evaluation benchmarks demonstrate that the proposed CM-based method has achieved promising performance for these two tasks.
入藏号: WOS:000424826800004
PubMed ID: 28222007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2168-2267
eISSN: 2168-2275
________________________________________
第 234 条,共 322 条
标题: A Hybrid Sparsity and Distance-Based Discrimination Detector for Hyperspectral Images
作者: Lu, XQ (Lu, Xiaoqiang); Zhang, WX (Zhang, Wuxia); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 卷: 56 期: 3 页: 1704-1717 DOI: 10.1109/TGRS.2017.2767068 出版年: MAR 2018
摘要: Hyperspectral target detection is an approach which tries to locate targets in a hyperspectral image on the condition of given targets spectrum. Many classical target detectors are based on the linear mixing model (LMM) and sparsity model. The LMM has a poor performance in dealing with the spectral variability. Therefore, more studies focus on the sparsity-based detectors, most of which are based on residual reconstruction. Owing to the fact that the impure dictionary for the test pixel weakens the detection performance and the discrimination ability of residual function has direct influence on the detecting accuracy, the dictionary purity and discriminative residual function are two most important factors affecting the accuracy of sparsity-based target detectors. In order to obtain more purified dictionary and discriminative residual function, this paper proposes a novel sparsity-based detector named the hybrid sparsity and distance-based discrimination (HSDD) detector for target detection in hyperspectral imagery. The residual function is constrained by the discrimination information during the dictionary construction, which enhances the dictionary purification. Only background samples are used to construct the dictionary because it is easier to remove the target pixel than to select it on the condition that majority of pixels are the background pixels. Hence, a purification process is applied for background training samples in order to construct an effective competition between the residual term and discriminative term. Extensive experimental results with four hyperspectral data sets demonstrate that the proposed HSDD algorithm has a better performance than the state-of-the-art algorithms.
入藏号: WOS:000426789800038
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0196-2892
eISSN: 1558-0644
________________________________________
第 235 条,共 322 条
标题: Auto-Weighted Multi-View Learning for Image Clustering and Semi-Supervised Classification
作者: Nie, FP (Nie, Feiping); Cai, GH (Cai, Guohao); Li, J (Li, Jing); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON IMAGE PROCESSING 卷: 27 期: 3 页: 1501-1511 DOI: 10.1109/TIP.2017.2754939 出版年: MAR 2018
摘要: Due to the efficiency of learning relationships and complex structures hidden in data, graph-oriented methods have been widely investigated and achieve promising performance. Generally, in the field of multi-view learning, these algorithms construct informative graph for each view, on which the following clustering or classification procedure are based. However, in many real-world data sets, original data always contain noises and outlying entries that result in unreliable and inaccurate graphs, which cannot be ameliorated in the previous methods. In this paper, we propose a novel multi-view learning model which performs clustering/semi-supervised classification and local structure learning simultaneously. The obtained optimal graph can be partitioned into specific clusters directly. Moreover, our model can allocate ideal weight for each view automatically without explicit weight definition and penalty parameters. An efficient algorithm is proposed to optimize this model. Extensive experimental results on different real-world data sets show that the proposed model outperforms other state-of-the-art multi-view algorithms.
入藏号: WOS:000418863500022
PubMed ID: 28945592
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Nie, Feiping         B-3039-2012         
Li, Xuelong         Z-3785-2019         
Nie, Feiping                  0000-0002-0871-6519
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1057-7149
eISSN: 1941-0042
________________________________________
第 236 条,共 322 条
标题: Identifying Objective and Subjective Words via Topic Modeling
作者: Wang, HQ (Wang, Hanqi); Wu, F (Wu, Fei); Lu, WM (Lu, Weiming); Yang, Y (Yang, Yi); Li, X (Li, Xi); Li, XL (Li, Xuelong); Zhuang, YT (Zhuang, Yueting)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 3 页: 718-730 DOI: 10.1109/TNNLS.2016.2626379 出版年: MAR 2018
摘要: It is observed that distinct words in a given document have either strong or weak ability in delivering facts (i.e., the objective sense) or expressing opinions (i.e., the subjective sense) depending on the topics they associate with. Motivated by the intuitive assumption that different words have varying degree of discriminative power in delivering the objective sense or the subjective sense with respect to their assigned topics, a model named as identified objective-subjective latent Dirichlet allocation (LDA) (iosLDA) is proposed in this paper. In the iosLDA model, the simple Polya urn model adopted in traditional topic models is modified by incorporating it with a probabilistic generative process, in which the novel "Bag-of-DiscriminativeWords" (BoDW) representation for the documents is obtained; each document has two different BoDW representations with regard to objective and subjective senses, respectively, which are employed in the joint objective and subjective classification instead of the traditional Bag-of-Topics representation. The experiments reported on documents and images demonstrate that: 1) the BoDW representation is more predictive than the traditional ones; 2) iosLDA boosts the performance of topic modeling via the joint discovery of latent topics and the different objective and subjective power hidden in every word; and 3) iosLDA has lower computational complexity than supervised LDA, especially under an increasing number of topics.
入藏号: WOS:000426344600018
PubMed ID: 28103560
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xi         L-1234-2013         
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197
Yang, Yi         B-9273-2017         0000-0002-0512-880X
Wang, Hanqi                  0000-0003-3549-3901

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 237 条,共 322 条
标题: Visible-extended mid-infrared wide spectrum detector based on InAs/GaSb type-II superlattices (T2SL)
作者: Guo, CY (Guo, Chunyan); Sun, YY (Sun, Yaoyao); Jia, Z (Jia, Zhe); Jiang, Z (Jiang, Zhi); Lv, YX (Lv, Yuexi); Hao, HY (Hao, Hongyue); Han, X (Han, Xi); Dong, YN (Dong, Yinan); Jiang, DW (Jiang, Dongwei); Wang, GW (Wang, Guowei); Xu, YQ (Xu, Yingqiang); Wang, T (Wang, Tao); Tian, JS (Tian, Jinshou); Wu, ZX (Wu, Zhaoxin); Niu, ZC (Niu, Zhichuan)
来源出版物: INFRARED PHYSICS & TECHNOLOGY 卷: 89 页: 147-153 DOI: 10.1016/j.infrared.2017.12.020 出版年: MAR 2018
摘要: The authors report an innovative design of wide spectrum detector that can detect visible and mid-infrared spectrum, from 0.4 to 5 mu m, simultaneously. The detector is designed with microstructure of various types of photon traps fabricated on mid-infrared InAs/GaSb type-II superlattice materials. Quantum efficiency has been significantly improved due to the action of photon traps which can decrease the reflectivity of the surface of InAs/GaSb type-II superlattice down to less than 5%. Under the condition of 77 K and 200 mV bias voltage, the responsivity of the detector is about 0.0250.45 A/W in the visible wavelength regime of 400-790 nm, more than 0.3 A/W in spectrum of 800-2000 nm, respectively. Through the optimized photon trap structure, the responsivity of detector is to 1.25 A/W and predominantly improve the quantum efficiency of the detector up to 52.5% at 3 mu m. (C) 2017 Published by Elsevier B.V.
入藏号: WOS:000428100900020
ISSN: 1350-4495
eISSN: 1879-0275
________________________________________
第 238 条,共 322 条
标题: Far-field super-oscillation imaging based on the super-oscillation elements and PSF feature extraction algorithm
作者: Xie, QK (Xie, Qingkun); Wang, J (Wang, Jing); Jiang, YR (Jiang, Yanru); Liang, J (Liang, Jian); Qu, ES (Qu, Enshi); Ren, LY (Ren, Liyong)
来源出版物: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION 卷: 35 期: 3 页: 491-495 DOI: 10.1364/JOSAA.35.000491 出版年: MAR 1 2018
摘要: Suffering from the limited number aperture, a resolution higher than 0.5. cannot be obtained in conventional far-field optical imaging systems. Recently, research of the optical super-oscillation lens (SOL) has been demonstrated to realize sub-diffractive focusing in both theory and practice successfully. Nevertheless, these systems usually have characteristics of a localized field of view and low-intensity focal spot surrounded by huge sidelobes, which profoundly restricts their application for super-resolution imaging. In this paper, we artificially segment the SOL into two simple-fabrication portions to generate the super-oscillation optical field and realize off-axis far-field imaging. Meanwhile, the point spread function (PSF) feature extraction algorithm is proposed to break the limitation of low core intensity of the PSF and then effectively extract the sub-diffractive structure annihilated by huge sidelobes. Simulations demonstrate its feasibility and reliability in sub-diffraction information recovery, and targets with a resolution of 250 nm are well recovered in the super-oscillation area. (C) 2018 Optical Society of America.
入藏号: WOS:000427443300016
PubMed ID: 29522053
ISSN: 1084-7529
eISSN: 1520-8532
________________________________________
第 239 条,共 322 条
标题: Tunable output-frequency filter algorithm for imaging through scattering media under LED illumination
作者: Zhou, ML (Zhou, Meiling); Singh, AK (Singh, Alok Kumar); Pedrini, G (Pedrini, Giancarlo); Osten, W (Osten, Wolfgang); Min, JW (Min, Junwei); Yao, BL (Yao, Baoli)
来源出版物: OPTICS COMMUNICATIONS 卷: 410 页: 160-163 DOI: 10.1016/j.optcom.2017.10.018 出版年: MAR 1 2018
摘要: We present a tunable output-frequency filter (TOF) algorithm to reconstruct the object from noisy experimental data under low-power partially coherent illumination, such as LED, when imaging through scattering media. In the iterative algorithm, we employ Gaussian functions with different filter windows at different stages of iteration process to reduce corruption from experimental noise to search for a global minimum in the reconstruction. In comparison with the conventional iterative phase retrieval algorithm, we demonstrate that the proposed TOF algorithm achieves consistent and reliable reconstruction in the presence of experimental noise. Moreover, the spatial resolution and distinctive features are retained in the reconstruction since the filter is applied only to the region outside the object. The feasibility of the proposed method is proved by experimental results. (c) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000418646100024
ISSN: 0030-4018
eISSN: 1873-0310
________________________________________
第 240 条,共 322 条
标题: Feedback mechanism based iterative metric learning for person re-identification
作者: Ren, YT (Ren, Yutao); Li, XL (Li, Xuelong); Lu, XQ (Lu, Xiaoqiang)
来源出版物: PATTERN RECOGNITION 卷: 75 特刊: SI 页: 99-111 DOI: 10.1016/j.patcog.2017.04.012 出版年: MAR 2018
摘要: Person re-identification problem is targeting to match people in the views of non-overlapped camera networks. It is an important task in the fields of computer vision and video surveillance. It shows great value in applications like surveillance and action recognition. Existing metric learning based methods measure the similarity of sample pairs by learning a metric space in which the positive pairs are closer than negative pairs. However, the appearance features undergo with drastic variation. Person re-identification is a typical small sample problem. It is hard to learn a robust projection of metric subspace that takes all the situations into consideration. The learned metric subspace is usually over-fitting to training dataset due to the strict metric learning constraint. And the hard pairs in training dataset will weaken the discrimination of matching pairs' similarity. To address these problems, a feedback mechanism based iterative metric learning method is proposed. The proposed method introduces a mean distance of multi-metric subspace to deal with the over-fitting problem. The joint discriminant optimal model on feedback top ranks matching pairs will enhance the discrimination of matching pairs' similarity. It is a robust and discriminative distance metric which measures the matching pairs similarity with distances of multiple metric projections learned by a set of training datasets. Aiming to learn the multi-metric subspace, the proposed method gives a feedback mechanism based approach which back propagates the top ranks identification results as pseudo training datasets. The effectiveness of proposed mean distance of multi-metric projection is analyzed and proved theoretically. And extensive experiments on three challenging datasets, VIPeR, GRID and CUHK01 are conducted. The results show that the proposed method achieves the best performance and improves the state-of-the-art rank-1 identification rates by 18.48%, 2.00% and 5.41% on three datasets respectively. (C) 2017 Elsevier Ltd. All rights reserved.
入藏号: WOS:000418971900011
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0031-3203
eISSN: 1873-5142
________________________________________
第 241 条,共 322 条
标题: Method to improve near-field nonlinearity of a high-power diode laser array on a microchannel cooler
作者: Zhang, HY (Zhang, Hongyou); Jia, YT (Jia, Yangtao); Cai, WS (Cai, Wanshao); Tao, CH (Tao, Chunhua); Zah, CE (Zah, Chung-en); Liu, XS (Liu, Xingsheng)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 3 文献号: 036115 DOI: 10.1117/1.OE.57.3.036115 出版年: MAR 2018
摘要: Due to thermal stress, each emitter in a semiconductor laser bar or array is vertically displaced along the p-n junction; the result is that each emitter is not in a line, called near-field nonlinearity. Near-field nonlinearity along a laser bar (also known as "SMILE" effect) degrades the laser beam brightness, which causes an adverse effect on optical coupling and beam shaping. A large SMILE value causes a large divergence angle after collimation and a wider line after collimation and focusing. We simulate the factors affecting the SMILE value of a high-power diode laser array on a microchannel cooler (MCC). According to the simulation results, we have fabricated a series of laser bars bonded on MCCs with lower SMILE value. After simulation and experiment analysis, we found the key factor to affect SMILE is the deformation of the thin MCC because of the distribution of strain and stress in it. We also decreased the SMILE value of 1-cm-wide full bar AuSn bonded on MCCs from 12 to 1 mu m by balancing force on MCC to minimize the deformation. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
入藏号: WOS:000429265500046
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
ZAH, CHUNG-EN         R-3016-2019         

ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 242 条,共 322 条
标题: High pumping-power fiber combiner for double-cladding fiber lasers and amplifiers
作者: Zheng, JK (Zheng, Jinkun); Zhao, W (Zhao, Wei); Zhao, BY (Zhao, Baoyin); Li, Z (Li, Zhe); Chang, C (Chang, Chang); Li, G (Li, Gang); Gao, Q (Gao, Qi); Ju, P (Ju, Pei); Gao, W (Gao, Wei); She, SF (She, Shengfei); Wu, P (Wu, Peng); Hou, CQ (Hou, Chaoqi); Li, WN (Li, Weinan)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 3 文献号: 036105 DOI: 10.1117/1.OE.57.3.036105 出版年: MAR 2018
摘要: A high pumping-power fiber combiner for backward pumping configurations is fabricated and demonstrated by manufacturing process refinement. The pump power handling capability of every pump fiber can extend to 600 W, corresponding to the average pump coupling efficiency of 94.83%. Totally, 2.67-kW output power with the beam quality factor M-2 of 1.41 was obtained, using this combiner in the fiber amplifier experimental setup. In addition, the temperature of the splicing region was less than 50.0 degrees C in the designed combiner under the action of circulating cooling water. The experimental results prove that the designed combiner is a promising integrated all-fiber device for multikilowatt continuous-wave fiber laser with excellent beam quality. (c) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
入藏号: WOS:000429265500036
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 243 条,共 322 条
标题: Near-infrared optical properties of Yb3+-doped silicate glass waveguides prepared by double-energy proton implantation
作者: Shen, XL (Shen, Xiao-Liang); Zhu, QF (Zhu, Qi-Feng); Zheng, RL (Zheng, Rui-Lin); Lv, P (Lv, Peng); Guo, HT (Guo, Hai-Tao); Liu, CX (Liu, Chun-Xiao)
来源出版物: RESULTS IN PHYSICS 卷: 8 页: 352-356 DOI: 10.1016/j.rinp.2017.12.040 出版年: MAR 2018
摘要: We report on the preparation and properties of an optical planar waveguide structure operating at 1539 nm in the Yb3+-doped silicate glass. The waveguide was formed by using (470 + 500) keV proton implantation at fluences of (1.0 + 2.0) x 10(16) ions/cm(2). The waveguiding characteristics including the guided-mode spectrum and the near-field image were investigated by the m-line technique and the finite-difference beam propagation method. The energy distribution for implanted protons and the refractive index profile for the proton-implanted waveguide were simulated by the stopping and range of ions in matter and the reflectivity calculation method. The proton-implanted Yb3+-doped silicate glass waveguide is a candidate for optoelectronic elements in the near-infrared region. (C) 2017 The Authors. Published by Elsevier B.V.
入藏号: WOS:000428027700052
ISSN: 2211-3797
________________________________________
第 244 条,共 322 条
标题: Dispersion nonlinearity analysis of immersed gratings
作者: Tang, Q (Tang, Qian); Guo, LX (Guo, Li-Xin)
来源出版物: APPLIED OPTICS 卷: 57 期: 7 页: 1548-1553 DOI: 10.1364/AO.57.001548 出版年: MAR 1 2018
摘要: An immersed grating is a novel diffraction grating with higher spectral resolution than the classical reflective grating given. Its diffractive surface is immersed in an optical material with high refractive index (n > 1). This article provides a comprehensive discussion of the nonlinear dispersion of an immersed grating based on the analysis of its diffraction angle and angular dispersion. (C) 2018 Optical Society of America
入藏号: WOS:000427133800032
PubMed ID: 29522000
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 245 条,共 322 条
标题: Incremental Learning With Saliency Map for Moving Object Detection
作者: Pang, YW (Pang, Yanwei); Ye, L (Ye, Li); Li, XL (Li, Xuelong); Pan, J (Pan, Jing)
来源出版物: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 卷: 28 期: 3 页: 640-651 DOI: 10.1109/TCSVT.2016.2630731 出版年: MAR 2018
摘要: Moving object detection is a key to intelligent video analysis. On the one hand, what moves are not only interesting objects but also noise and cluttered background. On the other hand, moving objects without rich texture are prone to not be detected. Therefore, there are undesirable false alarms and missed alarms in the results of many algorithms of moving object detection. To reduce the false alarms and missed alarms, in this paper we propose to incorporate a saliency map into an incremental subspace analysis framework in which the saliency map makes the estimated background have less of a chance than the foreground (i.e., moving objects) to contain salient objects. The proposed objective function systematically takes into account the properties of sparsity, low rank, connectivity, and saliency. An alternative minimization algorithm is proposed to seek the optimal solutions. The experimental results on both the Perception Test Images Sequences data set and Wallflower data set demonstrate that the proposed method is effective in reducing false alarms and missed alarms.
入藏号: WOS:000426693100007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1051-8215
eISSN: 1558-2205
________________________________________
第 246 条,共 322 条
标题: Rotation of an optically trapped vaterite microsphere measured using rotational Doppler effect
作者: Chen, XL (Chen, Xinlin); Xiao, GZ (Xiao, Guangzong); Xiong, W (Xiong, Wei); Yang, KY (Yang, Kaiyong); Luo, H (Luo, Hui); Yao, BL (Yao, Baoli)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 3 文献号: 036103 DOI: 10.1117/1.OE.57.3.036103 出版年: MAR 2018
摘要: The angular velocity of a vaterite microsphere spinning in the optical trap is measured using rotational Doppler effect. The perfectly spherical vaterite microspheres are synthesized via coprecipitation in the presence of silk fibroin nanospheres. When trapped by a circularly polarized beam, the vaterite microsphere is uniformly rotated in the trap center. The probe beams containing two Laguerre-Gaussian beams of opposite topological charge l = +/- 7, l = +/- 8, and l = +/- 9 are illuminated on the spinning vaterite. By analyzing the backscattered light, a frequency shift is observed scaling with the rotation rate of the vaterite microsphere. The multiplicative enhancement of the frequency shift proportion to the topological charge has greatly improved the measurement precision. The reliability and practicability of this approach are verified through varying the topological charge of the probe beam and the trapping laser power. In consideration of the excellent measurement precision of the rotation frequency, this technique might be generally applicable in studying the torsional properties of micro-objects. (c) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License.
入藏号: WOS:000429265500034
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 247 条,共 322 条
标题: High power all-polarization-maintaining photonic crystal fiber monolithic femtosecond nonlinear chirped-pulse amplifier
作者: Lv, ZG (Lv, Zhiguo); Yang, Z (Yang, Zhi); Li, F (Li, Feng); Yang, XJ (Yang, Xiaojun); Li, QL (Li, Qianglong); Zhang, X (Zhang, Xin); Wang, YS (Wang, Yishan); Zhao, W (Zhao, Wei)
来源出版物: OPTICS AND LASER TECHNOLOGY 卷: 100 页: 282-285 DOI: 10.1016/j.optlastec.2017.10.017 出版年: MAR 1 2018
摘要: We report on an experimental study on fully fusion spliced high power all-polarization-maintaining Yb-doped photonic crystal fiber (PCF) femtosecond nonlinear chirped-pulse amplifier (CPA), which features large values of the positive third-order dispersion (TOD) superposed from the single-mode fiber stretcher (SMFs) and grating-pair compressor. Compensation of the TOD is realized by means of self-phase modulation (SPM) induced nonlinear phase shift during amplification. Up to 9.8 W of compressed average power at 275 kHz repetition rates with 36 mu J pulse energy and 495 fs pulse width has been obtained. To the best of our knowledge, this is the highest output power generated from the strictly all-fiber nonlinear CPA amplifier in femtosecond domain, which provides a possibility for the industrialized promotion and development of the high energy femtosecond fiber laser. (C) 2017 Elsevier Ltd. All rights reserved.
入藏号: WOS:000417669700033
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
qianglong, li         V-6278-2019         

ISSN: 0030-3992
eISSN: 1879-2545
________________________________________
第 248 条,共 322 条
标题: Defect States Emerging from a Non-Hermitian Flatband of Photonic Zero Modes
作者: Qi, BK (Qi, Bingkun); Zhang, LX (Zhang, Lingxuan); Ge, L (Ge, Li)
来源出版物: PHYSICAL REVIEW LETTERS 卷: 120 期: 9 文献号: 093901 DOI: 10.1103/PhysRevLett.120.093901 出版年: FEB 27 2018
摘要: We show the existence of a flatband consisting of photonic zero modes in a gain and loss modulated lattice system as a result of the underlying non-Hermitian particle-hole symmetry. This general finding explains the previous observation in parity-time symmetric systems where non-Hermitian particle-hole symmetry is hidden. We further discuss the defect states in these systems, whose emergence can be viewed as an unconventional alignment of a pseudospin under the influence of a complex-valued pseudomagnetic field. These defect states also behave as a chain with two types of links, one rigid in a unit cell and one soft between unit cells, as the defect states become increasingly localized with the gain and loss strength.
入藏号: WOS:000426173800004
PubMed ID: 29547321
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Qi, Bingkun         X-1701-2019         
Ge, Li                  0000-0002-1922-4464

ISSN: 0031-9007
eISSN: 1079-7114
________________________________________
第 249 条,共 322 条
标题: Beat frequency error rectifying in multi-beam laser coherent remote tmaging
作者: Zhang, Y (Zhang Yu); Luo, XJ (Luo Xiu-Juan); Liu, H (Liu Hui); Chen, ML (Chen Ming-Lai); Lan, FY (Lan Fu-Yang); Jia, H (Jia Hui); Cao, B (Cao Bei)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 4 文献号: 044201 DOI: 10.7498/aps.67.20172125 出版年: FEB 20 2018
摘要: Coherent imaging with a multi-beam laser is considered as a key technique in ground based imaging. The image quality is directly determined by stability and consistency of each beam in transmitter. Although the stabilities of laser frequency and the drifting compensation methods have been studied previously, they mostly focused on the laser source. In most cases, especially in large transmitter array, however, transmitted beams are always disturbed by different influential factors, such as frequency drift induced by acoustic-optical modulation (AOM) and high power driven amplification. Therefore this kind of frequency drifting needs further rectification. Aiming at this problem, in this paper we propose two new methods called dynamic demodulation and dependence range demodulation. Firstly, the dynamic demodulation takes the whole drifting frequency drift as a changing procedure. It is believed that the beat frequency drifted at any position still carries the target information, so the system demodulates the signal at that drifted position. According to this method, the response speed of the demodulation system should be very high. But in a real system this acquisition is too high to be satisfied. It cannot work as quickly as expected. In computer simulation some slow varying drifts are induced at the beat frequency and the variation is distributed only in three parts of spatial frequency of transmitter interfering array. Simulation results show that this method may well compensate for slow drifting beat frequency. While its response speed is often limited by hardware system. On the other hand, for the dependence range demodulation, the beat drifting range is considered as a useful district, in which all the beat energy is added and demodulated at a preset position. An experiment is carried out to verify this method. The result demonstrates that it can well restrict the beat frequency drift within 100 Hz, which often happens in the procedure of AOM and driving amplification. Besides the laboratory setup research, the field experiments in 200 m and 1.5 km range are also carried out. The dependence range demodulation is proved to be well performed as well. The resolution of the 25 cm simulated target in 1.5 km reaches 0.008 rad. In the consideration of real system, the imaging range is further expanded and the amplifier power is stronger. The field experiments reveal that this demodulation method is applicable in such a condition. Therefore the research in this article provides some new techniques for the remote high resolution imaging in multi-beam laser interfering imaging.
入藏号: WOS:000428113200010
ISSN: 1000-3290
________________________________________
第 250 条,共 322 条
标题: Er-doped Q-switched fiber laser with a black phosphorus/polymethyl methacrylate saturable absorber
作者: Liu, SC (Liu, Sicong); Zhang, YN (Zhang, Yani); Li, L (Li, Lu); Wang, YG (Wang, Yonggang); Lv, RD (Lv, Ruidong); Wang, X (Wang, Xi); Chen, ZD (Chen, Zhendong); Wei, LL (Wei, Lianglei)
来源出版物: APPLIED OPTICS 卷: 57 期: 6 页: 1292-1295 DOI: 10.1364/AO.57.001292 出版年: FEB 20 2018
摘要: A stable Q-switched Er-doped fiber (EDF) laser is successfully obtained by using a black phosphorus (BP)/polymethyl methacrylate (PMMA) film as the saturable absorber (SA). To avoid the oxidization of nanomaterials, the BP nanoparticles are fabricated via a liquid-phase exfoliation method and then embedded into a PMMA film that possesses excellent optical transparency in the selected spectrum range. The modulation depth (MD) of the BP/PMMA film SA is 14.3% and the saturable intensity (I-sat) is 6.9 MW/cm(2). By inserting the BP/PMMA film into the EDF laser cavity, we achieve the stable passive Q-switching operation over the wavelength range from 1561.21 nm to 1564.16 nm. The repetition rate increases from 10.348 kHz to 30.098 kHz, and the pulse duration decreases from 25.01 mu s to 2.98 mu s by altering the pump power from 9 mWto 90 mW. The maximum single pulse energy is 283.91 nJ. To the best of our knowledge, 283.91 nJ is the largest single pulse energy among the Q-switched fiber lasers with BP as the Q-switcher at the 1.5 mu m wavelength region. The experimental results evidently show that the BP/PMMA film SA can work as a promising Q-switcher for large pulse energy fiber lasers. (c) 2018 Optical Society of America
入藏号: WOS:000425508300002
PubMed ID: 29469826
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Lu                  0000-0002-3097-1954

ISSN: 1559-128X
eISSN: 2155-3165
第 251 条,共 322 条
标题: Optimizing codes for compressed ultrafast photography by the genetic algorithm
作者: Yang, CS (Yang, Chengshuai); Qi, DL (Qi, Dalong); Wang, X (Wang, Xing); Cao, FY (Cao, Fengyan); He, YL (He, Yilin); Wen, WL (Wen, Wenlong); Jia, TQ (Jia, Tianqing); Tian, JS (Tian, Jinshou); Sun, ZR (Sun, Zhenrong); Gao, L (Gao, Liang); Zhang, SA (Zhang, Shian); Wang, LHV (Wang, Lihong V.)
来源出版物: OPTICA 卷: 5 期: 2 页: 147-151 DOI: 10.1364/OPTICA.5.000147 出版年: FEB 20 2018
摘要: The compressed ultrafast photography (CUP) technique, providing the fastest receive-only camera so far, has shown to be a well-established tool to capture the ultrafast dynamical scene. This technique is based on random codes to encode and decode the ultrafast dynamical scene by a compressed sensing algorithm. The choice of random codes significantly affects the image reconstruction quality. Therefore, it is important to optimize the encoding codes. Here, we develop a new scheme to obtain the optimized codes by combining a genetic algorithm (GA) into the CUP technique. First, we measure the dynamical scene by the CUP system with random codes and obtain the dynamical scene image at each moment. Second, we use these reconstructed dynamical scene images as the optimization target and optimize the encoding codes based on the GA. Finally, we utilize the optimized codes to recapture the dynamical scene and improve the image reconstruction quality. We validate our optimization scheme by the numerical simulation of a moving double-semielliptical spot and the experimental demonstration of a time-and space-evolving pulsed laser spot. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000425507400009
ISSN: 2334-2536
________________________________________
第 252 条,共 322 条
标题: Generation and coherent detection of QPSK signal using a novel method of digital signal processing
作者: Zhao, Y (Zhao, Yuan); Hu, BL (Hu, Bingliang); He, ZA (He, Zhen-An); Xie, WJ (Xie, Wenjia); Gao, XH (Gao, Xiaohui)
来源出版物: MODERN PHYSICS LETTERS B 卷: 32 期: 4 文献号: 1850103 DOI: 10.1142/S0217984918501038 出版年: FEB 10 2018
摘要: We demonstrate an optical quadrature phase-shift keying (QPSK) signal transmitter and an optical receiver for demodulating optical QPSK signal with homodyne detection and digital signal processing (DSP). DSP on the homodyne detection scheme is employed without locking the phase of the local oscillator (LO). In this paper, we present an extracting one-dimensional array of down-sampling method for reducing unwanted samples of constellation diagram measurement. Such a novel scheme embodies the following major advantages over the other conventional optical QPSK signal detection methods. First, this homodyne detection scheme does not need strict requirement on LO in comparison with linear optical sampling, such as having a flat spectral density and phase over the spectral support of the source under test. Second, the LabVIEW software is directly used for recovering the QPSK signal constellation without employing complex DSP circuit. Third, this scheme is applicable to multilevel modulation formats such as M-ary PSK and quadrature amplitude modulation (QAM) or higher speed signals by making minor changes.
入藏号: WOS:000424876900014
ISSN: 0217-9849
eISSN: 1793-6640
________________________________________
第 253 条,共 322 条
标题: Effect of the thermal treatment on the luminescence properties and dispersibility of LaF3: Nd nanoparticles in solvents
作者: Fan, Q (Fan, Qi); Cui, XX (Cui, Xiaoxia); Xu, YT (Xu, Yantao); Guo, HT (Guo, Haitao); Gao, F (Gao, Fei); Peng, B (Peng, Bo)
来源出版物: COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS 卷: 538 页: 423-428 DOI: 10.1016/j.colsurfa.2017.11.031 出版年: FEB 5 2018
摘要: To investigate the effect of thermal treatment on the optical properties of NPs dispersions more accurately, dehydrated mixed solvents of DMSO-d/CHBr2CHBr2 was applied to disperse the LaF3:Nd nanoparticles (NPs). These solvents contain few quenching groups and possess similar density, solubility and matching refractive index with LaF3:Nd NPs, which depressed the influence of solvents on the luminescent properties of NPs dispersions to the greatest extent. The effect of thermal treatment on the optical performance of the LaF3:Nd NPs dispersions were characterized by the transmittance, fluorescence spectra and lifetime. An influence model of particle size and relative refractive index on the scattering loss of NPs dispersions was established. An enhancement of lifetime by 60.7% and a suppression of transmittance were observed for the dispersions with LaF3:Nd NPs heat-treated at 500 degrees C. This is verified by the results of the scattering loss calculations based on the Mie scatter theory. These results can offer some constructive suggestions to evaluate the luminescence properties of rare-earth doped NPs in the solvents more accurately.
入藏号: WOS:000418586600050
ISSN: 0927-7757
eISSN: 1873-4359
________________________________________
第 254 条,共 322 条
标题: Advanced RF and microwave functions based on an integrated optical frequency comb source
作者: Xu, XY (Xu, Xingyuan); Wu, JY (Wu, Jiayang); Nguyen, TG (Nguyen, Thach G.); Shoeiby, M (Shoeiby, Mehrdad); Chu, ST (Chu, Sai T.); Little, BE (Little, Brent E.); Morandotti, R (Morandotti, Roberto); Mitchell, A (Mitchell, Arnan); Moss, DJ (Moss, David J.)
来源出版物: OPTICS EXPRESS 卷: 26 期: 3 页: 2569-2583 DOI: 10.1364/OE.26.002569 出版年: FEB 5 2018
摘要: We demonstrate advanced transversal radio frequency (RF) and microwave functions based on a Kerr optical comb source generated by an integrated micro-ring resonator. We achieve extremely high performance for an optical true time delay aimed at tunable phased array antenna applications, as well as reconfigurable microwave photonic filters. Our results agree well with theory. We show that our true time delay would yield a phased array antenna with features that include high angular resolution and a wide range of beam steering angles, while the microwave photonic filters feature high Q factors, wideband tunability, and highly reconfigurable filtering shapes. These results show that our approach is a competitive solution to implementing reconfigurable, high performance and potentially low cost RF and microwave signal processing functions for applications including radar and communication systems. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000425365900039
PubMed ID: 29401795
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wu, Jiayang         Q-8590-2019         0000-0003-1115-610X
Chu, Sai T         D-3312-2014         0000-0001-8263-8507
Mitchell, Arnan         C-5017-2008         0000-0002-2463-2956
Nguyen, Thach                  0000-0002-8409-5638
Xu, Xingyuan                  0000-0002-8190-4700

ISSN: 1094-4087
________________________________________
第 255 条,共 322 条
标题: Analysis and research of polarization aberration in rapid space angle measuring system
作者: Li, CY (Li Chun-Yan); Lu, WG (Lu Wei-Guo); Qiao, L (Qiao Lin)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 3 文献号: 030703 DOI: 10.7498/aps.67.20171702 出版年: FEB 5 2018
摘要: The precise angle measurement and transmission technology have been widely used in the precision measurement, aerospace, military, biomedicine and other devices, which are based on the polarized light and magneto-optical modulation. This method has the characteristics of no rigid connection required, long distance transmission, high precision, etc. However, the azimuth information measurement method needs the assistance of complex servo tracking system according to the orthogonal extinction principle of polarization prism, meanwhile, the measurement time is longer, which reduces reliability and reaction sensitivity of the system. In order to improve the measurement accuracy and fast response capability of the system, a fast space goniometry method is proposed through the Wollaston prism polarizing beam splitter, with which the azimuth is directly calculated according to the two light intensities. The measurement time can be shortened, and the accuracy is improved by the use of magneto-optical modulation technology. The rapid space angle measuring system needs to realize the measurement function in a certain translation range, which requires the beam to have a certain coverage area in the receiving unit. However, the system is limited by size and volume of the device; we can only choose to expand the incident beam. Therefore, when the beam is incident onto the receiving unit, some incident angle and azimuth, that is, non-vertical incidence will be produced. However, the polarization of the non-vertically incident light passing through the system will change and polarization aberration exists, which will lead to measurement error. In this paper, the beam passes through the polarizing prism in a certain range of azimuths and incident angles, and the polarized light tracing method and the boundary condition of the electromagnetic field are used to study and simulate the polarization change and distribution of the outgoing beam. The changes of different incident azimuths and angles can be simulated through the translation of receiving unit, and the azimuths can be measured indirectly by using self-collimation theodolite and right angle prism. By comparing the measured azimuths under the translational and centering conditions, the influence of polarization aberration on the angle measuring system and the correctness of the theoretical analysis are verified. It is concluded that when the azimuth angle is 0 degrees, the measurement error is small; when the azimuth is 90 degrees, the measurement error is largest, meanwhile the measurement error will increase with the translation distance becoming longer (i.e., the incident angle). According to the comparison between the experimental data and the simulation results, the existing problems are pointed out, and the corresponding improvement measures are proposed. The results of this work have some significance in guiding the optimization of the system structure, and the further improvement inthe performance of the system.
入藏号: WOS:000425272200006
ISSN: 1000-3290
________________________________________
第 256 条,共 322 条
标题: A Review of Co-Saliency Detection Algorithms: Fundamentals, Applications, and Challenges
作者: Zhang, DW (Zhang, Dingwen); Fu, HZ (Fu, Huazhu); Han, JW (Han, Junwei); Borji, A (Borji, Ali); Li, XL (Li, Xuelong)
来源出版物: ACM TRANSACTIONS ON INTELLIGENT SYSTEMS AND TECHNOLOGY 卷: 9 期: 4 文献号: 38 DOI: 10.1145/3158674 出版年: FEB 2018
摘要: Co-saliency detection is a newly emerging and rapidly growing research area in the computer vision community. As a novel branch of visual saliency, co-saliency detection refers to the discovery of common and salient foregrounds from two or more relevant images, and it can be widely used in many computer vision tasks. The existing co-saliency detection algorithms mainly consist of three components: extracting effective features to represent the image regions, exploring the informative cues or factors to characterize co-saliency, and designing effective computational frameworks to formulate co-saliency. Although numerous methods have been developed, the literature is still lacking a deep review and evaluation of co-saliency detection techniques. In this article, we aim at providing a comprehensive review of the fundamentals, challenges, and applications of co-saliency detection. Specifically, we provide an overview of some related computer vision works, review the history of co-saliency detection, summarize and categorize the major algorithms in this research area, discuss some open issues in this area, present the potential applications of co-saliency detection, and finally point out some unsolved challenges and promising future works. We expect this review to be beneficial to both fresh and senior researchers in this field and to give insights to researchers in other related areas regarding the utility of co-saliency detection algorithms.
入藏号: WOS:000425718800001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Fu, Huazhu         A-1411-2014         0000-0002-9702-5524
zhang, dingwen         R-3463-2019         0000-0001-8369-8886
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2157-6904
eISSN: 2157-6912
________________________________________
第 257 条,共 322 条
标题: Effect of Lamina Thickness of Prepreg on the Surface Accuracy of Carbon Fiber Composite Space Mirrors
作者: Yang, ZY (Yang, Zhiyong); Tang, ZW (Tang, Zhanwen); Xie, YJ (Xie, Yongjie); Shi, HQ (Shi, Hanqiao); Zhang, BM (Zhang, Boming); Guo, HJ (Guo, Hongjun)
来源出版物: APPLIED COMPOSITE MATERIALS 卷: 25 期: 1 页: 105-112 DOI: 10.1007/s10443-017-9604-x 出版年: FEB 2018
摘要: Composite space mirror can completely replicate the high-precision surface of mould by replication process, but the actual surface accuracy of the replication composite mirror always decreases. Lamina thickness of prepreg affects the layers and layup sequence of composite space mirror, and which would affect surface accuracy of space mirror. In our research, two groups of contrasting cases through finite element analyses (FEA) and comparative experiments were studied; the effect of different lamina thicknesses of prepreg and corresponding lay-up sequences was focused as well. We describe a special analysis model, validated process and result analysis. The simulated and measured surface figures both get the same conclusion. Reducing lamina thickness of prepreg used in replicating composite space mirror is propitious to optimal design of layup sequence for fabricating composite mirror, and could improve its surface accuracy.
入藏号: WOS:000423393900007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
zhang, boming                  0000-0003-4430-3997

ISSN: 0929-189X
eISSN: 1573-4897
________________________________________
第 258 条,共 322 条
标题: Learning to Predict Eye Fixations via Multiresolution Convolutional Neural Networks
作者: Liu, NA (Liu, Nian); Han, JW (Han, Junwei); Liu, TM (Liu, Tianming); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS 卷: 29 期: 2 页: 392-404 DOI: 10.1109/TNNLS.2016.2628878 出版年: FEB 2018
摘要: Eye movements in the case of freely viewing natural scenes are believed to be guided by local contrast, global contrast, and top-down visual factors. Although a lot of previous works have explored these three saliency cues for several years, there still exists much room for improvement on how to model them and integrate them effectively. This paper proposes a novel computation model to predict eye fixations, which adopts a multiresolution convolutional neural network (Mr-CNN) to infer these three types of saliency cues from raw image data simultaneously. The proposed Mr-CNN is trained directly from fixation and nonfixation pixels with multiresolution input image regions with different contexts. It utilizes image pixels as inputs and eye fixation points as labels. Then, both the local and global contrasts are learned by fusing information in multiple contexts. Meanwhile, various top-down factors are learned in higher layers. Finally, optimal combination of top-down factors and bottom-up contrasts can be learned to predict eye fixations. The proposed approach significantly outperforms the state-of-the-art methods on several publically available benchmark databases, demonstrating the superiority of Mr-CNN. We also apply our method to the RGB-D image saliency detection problem. Through learning saliency cues induced by depth and RGB information on pixel level jointly and their interactions, our model achieves better performance on predicting eye fixations in RGB-D images.
入藏号: WOS:000422952400013
PubMed ID: 27913362
会议名称: IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
会议日期: JUN 07-12, 2015
会议地点: Boston, MA
会议赞助商: IEEE
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2162-237X
eISSN: 2162-2388
________________________________________
第 259 条,共 322 条
标题: Band selection of hyperspectral image based on optimal linear prediction of principal components in subspace
作者: Wu, YQ (Wu Yi-Quan); Zhou, Y (Zhou Yang); Sheng, DH (Sheng Dong-Hui); Ye, XL (Ye Xiao-Lai)
来源出版物: JOURNAL OF INFRARED AND MILLIMETER WAVES 卷: 37 期: 1 页: 119-128 DOI: 10.11972/j.issn.1001-9014.2018.01.021 出版年: FEB 2018
摘要: In the case of hyperspectral anomaly detection, in order to make hyperspectral low-dimensional data preserve the spectral information more completely, a band selection method based on the optimal linear prediction of principal components in subspace was proposed. Hyperspectral bands are divided into different subspaces by spectral clustering with the improved correlation measure. The principal component analysis (PCA) of bands is presented in each subspace, and main components are selected as the reconstructed targets. The subspace tracking method serves as the search strategy, and several bands are selected from each subspace to perform the joint optimal linear prediction of reconstructed targets. The selected bands in each subspace are combined to obtain the optimal band subset. Experimental results show that, the proposed method can reconstruct the original data more completely. Compared with original data, and the band subsets obtained by adaptive band selection (ABS) method, linear prediction (LP) method, maximum-variance principal component analysis (MVPCA) method, auto correlation matrix based band selection (ACMBS) method and optimal combination factors-based band selection (OCFBS) method, the band subset of proposed method has superior performance of anomaly detection.
入藏号: WOS:000430645900021
ISSN: 1001-9014
________________________________________
第 260 条,共 322 条
标题: Design of a control system with high stability for a streak camera using isolated ADC
作者: Fang, YM (Fang, Yu-Man); Xu, XY (Xu, Xiang-Yan); Tian, JS (Tian, Jin-Shou); Pei, CQ (Pei, Cheng-Quan)
来源出版物: NUCLEAR SCIENCE AND TECHNIQUES 卷: 29 期: 2 文献号: 22 DOI: 10.1007/s41365-018-0361-9 出版年: FEB 2018
摘要: The streak camera is an ultra-fast diagnostic instrument with high sensitivity, and a high temporal and spatial resolution. It is primarily employed in various scientific research, such as inertial confinement fusion (ICF), synchrotron light sources, and electron-positron colliders. An automatic control system for an X-ray streak camera is presented in this paper. The output terminal of an analog-to-digital converter was isolated from its input terminal, to reduce interference from high-voltage electrodes. Compared with traditional methods, this scheme also improved the internal electromagnetic interface immunity. Therefore, the system stability was enhanced. With this optimized control system, some characterizations of the streak camera were measured. Static and dynamic spatial resolutions of 25 and 20 lp/mm (CTF = 20%), respectively, were obtained. In addition, a dynamic range of 552:1 and a temporal resolution of 7.3 ps were achieved. The results confirmed that these characterizations are sufficient for the specifications derived from the diagnostic requirements of ICF.
入藏号: WOS:000427326900006
ISSN: 1001-8042
eISSN: 2210-3147
________________________________________
第 261 条,共 322 条
标题: Study on Cesium Adsorption/Desorption Behavior of Porous Nickel
作者: Hu, WJ (Hu, Weijie); Wang, HJ (Wang, Haojing); Guo, B (Guo, Bin); Li, WL (Li, Wenlong); Zhou, QQ (Zhou, Qianqian)
来源出版物: RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 卷: 92 期: 2 页: 373-380 DOI: 10.1134/S0036024418020267 出版年: FEB 2018
摘要: A simplified two-dimensional mode of is established for the performance, characteristics and transportation behavior in cesium adsorption/desorption process. Subsequently the cesium absorption/ desorption ability of porous nickel were investigated by batch experiment on the condition that the pressure is lower than 10 Pa in self-made quarz vacuum device containing porous nickel with the appropriate structural features and parameters simulated above. The experiment results indicate that about 95% of cesium can be desorbed quickly and effectively with a stable process from the porous nickel show that the simulation model and the analysis method are correct and feasible which can be used as a basis for further study. According to the detailed simulation result, model reveal the considered porous nickel could be used for feasibility of cesium adsorption/desorption, which is fully meeting the application need of both higher storage capacity and stable desorption efficiency in lower pressure ambient condition.
入藏号: WOS:000426961600028
ISSN: 0036-0244
eISSN: 1531-863X
________________________________________
第 262 条,共 322 条
标题: Hyperspectral data classification based on flexible momentum deep convolution neural network
作者: Yue, Q (Yue, Qi); Ma, CW (Ma, Caiwen)
来源出版物: MULTIMEDIA TOOLS AND APPLICATIONS 卷: 77 期: 4 页: 4417-4429 DOI: 10.1007/s11042-017-4734-6 出版年: FEB 2018
摘要: Classification is a hot topic in hyperspectral remote sensing community. In the last decades, numerous effort has been concentrate on the classification problem. However, most of the methods accuracy is not high enough due to the fact that they do not extract features in a deep manner. In this paper, a new hyperspectral data classification skeleton based on exponential flexible momentum deep convolution neural network (EFM-CNN) is proposed. First, the fitness of convolution neural network is substantiated by following classical spectral information-based classification. Then, a novel deep architecture is proposed, which is a hybrid of principle component analysis (PCA), improved convolution neural network based on exponential flexible momentum and support vector machine (SVM). Experimental results indicate that the classifier can effectively improve the accuracy with the state-of-the-art algorithms. And compared with homologous parameters momentum updating methods such as adaptive momentum method, standard momentum gradient method and elastic momentum method, on LeNet5 net and multiple neural network, the accuracy obtained of proposed algorithm increases by 2.6% and 6.5% on average respectively.
入藏号: WOS:000425296500021
ISSN: 1380-7501
eISSN: 1573-7721
________________________________________
第 263 条,共 322 条
标题: A novel simultaneous streak and framing camera without principle errors
作者: Jingzhen, L (Jingzhen, L.); Fengshan, S (Fengshan, S.); Ningwen, L (Ningwen, L.); Xiangdong, G (Xiangdong, G.); Bin, H (Bin, H.); Qingyang, W (Qingyang, W.); Hongyi, C (Hongyi, C.); Yi, C (Yi, C.); Xiaowei, L (Xiaowei, L.)
来源出版物: JOURNAL OF INSTRUMENTATION 卷: 13 文献号: P02024 DOI: 10.1088/1748-0221/13/02/P02024 出版年: FEB 2018
摘要: A novel simultaneous streak and framing camera with continuous access, the perfect information of which is far more important for the exact interpretation and precise evaluation of many detonation events and shockwave phenomena, has been developed. The camera with the maximum imaging frequency of 2 X 10(6) fps and the maximum scanning velocity of 16.3 mm/mu s has fine imaging properties which are the eigen resolution of over 40 lp/mm in the temporal direction and over 60 lp/mm in the spatial direction and the framing frequency principle error of zero for framing record, and the maximum time resolving power of 8 ns and the scanning velocity nonuniformity of 0.136% similar to 0.277% for streak record. The test data have verified the performance of the camera quantitatively.
This camera, simultaneously gained frames and streak with parallax-free and identical time base, is characterized by the plane optical system at oblique incidence different from space system, the innovative camera obscura without principle errors, and the high velocity motor driven beryllium-like rotating mirror, made of high strength aluminum alloy with cellular lateral structure.
Experiments demonstrate that the camera is very useful and reliable to take high quality pictures of the detonation events.
入藏号: WOS:000425938100001
ISSN: 1748-0221
________________________________________
第 264 条,共 322 条
标题: In-Line Mach-Zehnder Interferometer With D-Shaped Fiber Grating for Temperature-Discriminated Directional Curvature Measurement
作者: Jiang, BQ (Jiang, Biqiang); Bai, ZY (Bai, Zhiyong); Wang, CL (Wang, Changle); Zhao, YH (Zhao, Yunhe); Zhao, JL (Zhao, Jianlin); Zhang, L (Zhang, Lin); Zhou, KM (Zhou, Kaiming)
来源出版物: JOURNAL OF LIGHTWAVE TECHNOLOGY 卷: 36 期: 3 页: 742-747 DOI: 10.1109/JLT.2017.2776297 出版年: FEB 1 2018
摘要: A high-sensitivity curvature sensing configuration is implemented by using a fiberMach-Zehnder interferometer (MZI) with D-shaped fiber Bragg grating (FBG). A segment of D-shaped fiber is fusion spliced into a single mode fiber at both sides, and then a shortFBGis inscribed in the D-shaped fiber. The fiber device yields a significant spectrum sensitivity as high as 87.7 nm/m(-1) to the ultralow curvature range from 0 to 0.3 m(-1), and can distinguish the orientation of curvature experienced by the fiber as the attenuation dip producing either a blue or red wavelength shift, by virtue of the asymmetry of D-shaped fiber cladding. In addition, by tracking both resonant wavelengths of the MZI and embedded FBG, the temperature and curvature can be measured simultaneously.
入藏号: WOS:000425207100015
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Jiang, Biqiang         M-8939-2018         0000-0003-2563-3464
Zhao, Yunhe                  0000-0002-6912-5245

ISSN: 0733-8724
eISSN: 1558-2213
________________________________________
第 265 条,共 322 条
标题: Single-polarization operation in suspended-core microstructured fibers
作者: Zhu, YF (Zhu, Yuan-Feng); Kong, DP (Kong, Depeng); Ye, ZQ (Ye, Zhi-Qing); Rao, CF (Rao, Chun-Fang); Zhong, H (Zhong, Hua)
来源出版物: PHOTONICS AND NANOSTRUCTURES-FUNDAMENTALS AND APPLICATIONS 卷: 28 页: 6-11 DOI: 10.1016/j.photonics.2017.11.004 出版年: FEB 2018
摘要: We present the design and investigation of a single-polarization suspended-core fiber with an elliptical core consisting of crossed rectangular-shaped dielectric strips. By optimizing the fiber configuration parameters, single-polarization single-mode transmission with a bandwidth of 400 nm can be obtained. Also, the power fraction in air of the x-polarization fundamental mode is relatively high, which facilitates its applications in high precision sensors. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000424961500002
ISSN: 1569-4410
eISSN: 1569-4429
________________________________________
第 266 条,共 322 条
标题: Broadband self-collimating phenomenon in a low-loss hybrid plasmonic photonic crystal
作者: Zhang, LX (Zhang, Lingxuan); Zhang, WF (Zhang, Wenfu); Wang, GX (Wang, Guoxi); Li, ZY (Li, Zhongyu); Du, SJ (Du, Shujian); Wang, WQ (Wang, Weiqiang); Wang, LR (Wang, Leiran); Sun, QB (Sun, Qibing); Zhao, W (Zhao, Wei)
来源出版物: APPLIED OPTICS 卷: 57 期: 4 页: 829-833 DOI: 10.1364/AO.57.000829 出版年: FEB 1 2018
摘要: A 2D planar self-collimating photonic crystal, based on a dielectric square lattice and a hexagonal lattice, is proposed. We demonstrate that the proposed structure can support the propagation of a hybrid surface plasmon polarition (SPP) mode with a loss of -0.017 dB/mu m, and the mode size is only 0.33 mu m. The defined figure of merit is one order of magnitude higher than that of the dielectric-metal structure. In addition, the self-collimating angle of more than 10 degrees can be tuned with a silica index change of 0.08. The proposed structure possesses broad operation bandwidth of 88 nm and 58 nm for a dielectric square lattice and a hexagonal lattice, respectively. These two kinds of photonic crystals promise potential applications in photonic modulators and SPP photonic devices. (C) 2018 Optical Society of America
入藏号: WOS:000424678900039
PubMed ID: 29400747
ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 267 条,共 322 条
标题: Front-surface fabrication of moderate aspect ratio micro-channels in fused silica by single picosecond Gaussian-Bessel laser pulse
作者: Liu, X (Liu, Xin); Sanner, N (Sanner, Nicolas); Sentis, M (Sentis, Marc); Stoian, R (Stoian, Razvan); Zhao, W (Zhao, Wei); Cheng, GH (Cheng, Guanghua); Uteza, O (Uteza, Olivier)
来源出版物: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING 卷: 124 期: 2 文献号: 206 DOI: 10.1007/s00339-018-1634-1 出版年: FEB 2018
摘要: Single-shot Gaussian-Bessel laser beams of 1 ps pulse duration and of similar to 0.9 mu m core size and similar to 60 mu m depth of focus are used for drilling micro-channels on front side of fused silica in ambient condition. Channels ablated at different pulse energies are fully characterized by AFM and post-processing polishing procedures. We identify experimental energy conditions (typically 1.5 mu J) suitable to fabricate non-tapered channels with mean diameter of similar to 1.2 mu m and length of similar to 40 mu m while maintaining an utmost quality of the front opening of the channels. In addition, by further applying accurate post-polishing procedure, channels with high surface quality and moderate aspect ratio down to a few units are accessible, which would find interest in the surface micro-structuring of materials, with perspective of further scalability to meta-material specifications.
入藏号: WOS:000424515500126
ISSN: 0947-8396
eISSN: 1432-0630
________________________________________
第 268 条,共 322 条
标题: Spinning of particles in optical double-vortex beams
作者: Li, MM (Li, Manman); Yan, SH (Yan, Shaohui); Liang, YS (Liang, Yansheng); Zhang, P (Zhang, Peng); Yao, BL (Yao, Baoli)
来源出版物: JOURNAL OF OPTICS 卷: 20 期: 2 文献号: 025401 DOI: 10.1088/2040-8986/aaa0e9 出版年: FEB 2018
摘要: Optical spin angular momentum, an intrinsic part of optical angular momemtum, can induce a spinning motion of a trapped particle around its own axis in optical manipulation. Focusing of a type of double-vortex (DV) input field obtained by linearly superposing two optical vortex beams with equal but opposite topological charges, yields a multi-lobe focal field, each of which has non-vanishing optical spin angular momentum, and is capable of trapping particle while spinning the particle around a certain axis. Significantly, both the focusing properties and the spinning dynamics are strongly polarization dependent. For instance, the focused field of a circularly polarized double-vortex (CPDV) beam carries transverse and longitudinal spin angular momenta, inducing axial spinning of the trapped particles, whereas the focused field of a radially polarized double-vortex (RPDV) beam possesses purely transverse spin angular momentum and can drive the particles to spin transversely to the optical axis. These results may find potential applications in light beam shaping and optical manipulations.
入藏号: WOS:000422736500001
ISSN: 2040-8978
eISSN: 2040-8986
________________________________________
第 269 条,共 322 条
标题: Two-dimensional matter-wave solitons and vortices in competing cubic-quintic nonlinear lattices
作者: Gao, XZ (Gao, Xuzhen); Zeng, JH (Zeng, Jianhua)
来源出版物: FRONTIERS OF PHYSICS 卷: 13 期: 1 文献号: 130501 DOI: 10.1007/s11467-017-0697-3 出版年: FEB 2018
摘要: The nonlinear lattice - a new and nonlinear class of periodic potentials was recently introduced to generate various nonlinear localized modes. Several attempts failed to stabilize two-dimensional (2D) solitons against their intrinsic critical collapse in Kerr media. Here, we provide a possibility for supporting 2D matter-wave solitons and vortices in an extended setting - the cubic and quintic model - by introducing another nonlinear lattice whose period is controllable and can be different from its cubic counterpart, to its quintic nonlinearity, therefore making a fully "nonlinear quasi-crystal". A variational approximation based on Gaussian ansatz is developed for the fundamental solitons and in particular, their stability exactly follows the inverted Vakhitov-Kolokolov stability criterion, whereas the vortex solitons are only studied by means of numerical methods. Stability regions for two types of localized mode - the fundamental and vortex solitons - are provided. A noteworthy feature of the localized solutions is that the vortex solitons are stable only when the period of the quintic nonlinear lattice is the same as the cubic one or when the quintic nonlinearity is constant, while the stable fundamental solitons can be created under looser conditions. Our physical setting (cubic-quintic model) is in the framework of the Gross-Pitaevskii equation or nonlinear Schrodinger equation, the predicted localized modes thus may be implemented in Bose-Einstein condensates and nonlinear optical media with tunable cubic and quintic nonlinearities.
入藏号: WOS:000414316800002
ISSN: 2095-0462
________________________________________
第 270 条,共 322 条
标题: Facial feature point detection: A comprehensive survey
作者: Wang, NN (Wang, Nannan); Gao, XB (Gao, Xinbo); Tao, DC (Tao, Dacheng); Yang, H (Yang, Heng); Li, XL (Li, Xuelong)
来源出版物: NEUROCOMPUTING 卷: 275 页: 50-65 DOI: 10.1016/j.neucom.2017.05.013 出版年: JAN 31 2018
摘要: This paper presents a comprehensive survey of facial feature point detection with the assistance of abundant manually labeled images. Facial feature point detection favors many applications such as face recognition, animation, tracking, hallucination, expression analysis and 3D face modeling. Existing methods are categorized into two primary categories according to whether there is the need of a parametric shape model: parametric shape model-based methods and nonparametric shape model-based methods. Parametric shape model-based methods are further divided into two secondary classes according to their appearance models: local part model-based methods (e.g. constrained local model) and holistic model-based methods (e.g. active appearance model). Nonparametric shape model-based methods are divided into several groups according to their model construction process: exemplar-based methods, graphical model-based methods, cascaded regression-based methods, and deep learning based methods. Though significant progress has been made, facial feature point detection is still limited in its success by wild and real-world conditions: large variations across poses, expressions, illuminations, and occlusions. A comparative illustration and analysis of representative methods provides us a holistic understanding and deep insight into facial feature point detection, which also motivates us to further explore more promising future schemes. (c) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000418370200006
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 271 条,共 322 条
标题: Randomly translational activation inspired by the input distributions of ReLU
作者: Cao, JL (Cao, Jiale); Pang, YW (Pang, Yanwei); Li, XL (Li, Xuelong); Liang, JK (Liang, Jingkun)
来源出版物: NEUROCOMPUTING 卷: 275 页: 859-868 DOI: 10.1016/j.neucom.2017.09.031 出版年: JAN 31 2018
摘要: Deep convolutional neural networks have achieved great success on many visual tasks (e.g., image classification). Non-linear activation plays a very important role in deep convolutional neural networks (CNN). It is found that the input distribution of non-linear activation is like Gaussian distribution and the most of the inputs are concentrated near zero. It makes the learned CNN likely sensitive to the small jitter of the non-linear activation input. Meanwhile, CNN is easily prone to overfitting with deep architecture. To solve the above problems, we make full use of the input distributions of non-linear activation and propose the randomly translational non-linear activation for deep CNN. In the training stage, non-linear activation function is randomly translated by an offset sampled from Gaussian distribution. In the test stage, the non-linear activation with zero offset is used. Based on our proposed method, the input distribution of non-linear activation is relatively scattered. As the result, the learned CNN is robust to the small jitter of the non-linear activation input. Our proposed method can be also seen as the regularization of non-linear activation to reduce overfitting. Compared to the original non-linear activation, our proposed method can improve classification accuracy without increasing computation cost. Experimental results on CIFAR-10/CIFAR-100, SVHN, and ImageNet demonstrate the effectiveness of the proposed method. For example, the reductions of error rates with VGG architecture on CIFAR-10/CIFAR-100 are 0.55% and 1.61%, respectively. Even when the noise is added to the input image, our proposed method still has much better classification accuracy on CIFAR-10/CIFAR-100. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000418370200081
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 272 条,共 322 条
标题: Deep neural networks with Elastic Rectified Linear Units for object recognition
作者: Jiang, XH (Jiang, Xiaoheng); Pang, YW (Pang, Yanwei); Li, XL (Li, Xuelong); Pan, J (Pan, Jing); Xie, YH (Xie, Yinghong)
来源出版物: NEUROCOMPUTING 卷: 275 页: 1132-1139 DOI: 10.1016/j.neucom.2017.09.056 出版年: JAN 31 2018
摘要: Rectified Linear Unit (ReLU) is crucial to the recent success of deep neural networks (DNNs). In this paper, we propose a novel Elastic Rectified Linear Unit (EReLU) that focuses on processing the positive part of input. Unlike previous variants of ReLU that typically adopt linear or piecewise linear functions to represent the positive part, EReLU is characterized by that each positive value scales within a moderate range like a spring during training stage. On test time, EReLU becomes standard ReLU. EReLU improves model fitting with no extra parameters and little overfitting risk. Furthermore, we propose Elastic Parametric Rectified Linear Unit (EPReLU) by taking advantage of EReLU and parametric ReLU (PReLU). EPReLU is able to further improve the performance of networks. In addition, we present a new training strategy to train DNNs with EPReLU. Experiments on four benchmarks including CIFAR10, CIFAR10, SVHN and ImageNet 2012 demonstrate the effectiveness of both EReLU and EPReLU. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000418370200108
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 0925-2312
eISSN: 1872-8286
________________________________________
第 273 条,共 322 条
标题: Controllable mode transformation in perfect optical vortices
作者: Li, XZ (Li, Xinzhong); Ma, HX (Ma, Haixiang); Yin, CL (Yin, Chuanlei); Tang, J (Tang, Jie); Li, HH (Li, Hehe); Tang, MM (Tang, Miaomiao); Wang, JG (Wang, Jingge); Tai, YP (Tai, Yuping); Li, XF (Li, Xiufang); Wang, YS (Wang, Yishan)
来源出版物: OPTICS EXPRESS 卷: 26 期: 2 页: 651-662 DOI: 10.1364/OE.26.000651 出版年: JAN 22 2018
摘要: We report a novel method to freely transform the modes of a perfect optical vortex (POV). By adjusting the scaling factor of the Bessel-Gauss beam at the object plane, the POV mode transformation can be easily controlled from circle to ellipse with a high mode purity. Combined with the modulation of the cone angle of an axicon, the ellipse mode can be freely adjusted along the two orthogonal directions. The properties of the "perfect vortex" are experimentally verified. Moreover, fractional elliptic POVs with versatile modes are presented, where the number and position of the gaps are controllable. These findings are significant for applications that require the complex structured optical field of the POV. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000422935900026
PubMed ID: 29401947
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xinzhong         P-7966-2018         0000-0002-6426-4043
Ma, Haixiang                  0000-0001-9422-9372

ISSN: 1094-4087
________________________________________
第 274 条,共 322 条
标题: Femtosecond laser Bessel beam welding of transparent to non-transparent materials with large focal-position tolerant zone
作者: Zhang, GD (Zhang, Guodong); Stoian, R (Stoian, Razvan); Zhao, W (Zhao, Wei); Cheng, GH (Cheng, Guanghua)
来源出版物: OPTICS EXPRESS 卷: 26 期: 2 页: 917-926 DOI: 10.1364/OE.26.000917 出版年: JAN 22 2018
摘要: It is known that ultrashort laser welding of materials requires an accurate laser beam focusing and positioning onto the samples interface. This puts forward severe challenges for controlling the focus position particularly considering that the tightly focused Gaussian beam has a short, micron-sized Rayleigh range. Here we propose a large-focal-depth welding method to bond materials by using non-diffractive femtosecond laser Bessel beams. A zero-order Bessel beam is produced by an axicon and directly imaged on the interface between silicon and borosilicate glass to write welding lines, ensuring a non-diffractive length in the 500 mu m range and micron-sized FWHM diameter. The focal-position tolerant zone for effective welding increases thus many-fold compared to traditional Gaussian beam welding. The shear joining strength of the sample welded by this method could be as high as 16.5 MPa. The Raman spectrum and element distribution analyses within the cross section of welding line reveal that substance mixing has occurred during laser irradiation, which is considered as the main reason for femtosecond laser induced bonding. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000422935900050
PubMed ID: 29401971
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Stoian, Razvan                  0000-0003-2107-9515

ISSN: 1094-4087
________________________________________
第 275 条,共 322 条
标题: Planar polarization-routing optical cross-connects using nematic liquid crystal waveguides
作者: Li, TG (Li, Tenghao); Chen, QM (Chen, Qingming); Yu, WX (Yu, Weixing); Zhang, XM (Zhang, Xuming)
来源出版物: OPTICS EXPRESS 卷: 26 期: 1 页: 402-418 DOI: 10.1364/OE.26.000402 出版年: JAN 8 2018
摘要: This paper presents the device design and performance analysis of a novel design of planar optical cross-connect (OXC) using nematic liquid crystal (NLC) waveguides. It employs N x N switching matrix in cross-bar fabric. In each unit cell, the input light is set in either the transverse electric (TE) mode or the transverse magnetic (TM) mode by electrically reorienting the NLC in the waveguide. The light then enters a passive waveguide and is routed to different paths depending on the polarization state (TE/TM mode). A sample device of 8 x 8 OXC is analyzed for performance estimation, which predicts a maximum on-chip insertion loss of 3 dB, an average cross-talk of -40 dB, similar to 1 ms switching time, and 2 mm x 2 mm footprint. The proposed OXC is unique in the switching mechanism of polarization-dependent routing and allows non-blocking switching with high compactness and broad bandwidth. It is potential for optical circuit switching in data centers and optical communication networks. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
入藏号: WOS:000419549600037
PubMed ID: 29328317
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Weixing         G-3658-2012         0000-0002-3216-526X

ISSN: 1094-4087
________________________________________
第 276 条,共 322 条
标题: High resolution electron bombareded complementary metal oxide semiconductor sensor for ultraviolet detection
作者: Liu, HL (Liu Hu-Lin); Wang, X (Wang Xing); Tian, JS (Tian Jin-Shou); Sai, XF (Sai Xiao-Feng); Wei, YL (Wei Yong-Lin); Wen, WL (Wen Wen-Long); Wang, JF (Wang Jun-Feng); Xu, XY (Xu Xiang-Yan); Wang, C (Wang Chao); Lu, Y (Lu Yu); He, K (He Kai); Chen, P (Chen Ping); Xin, LW (Xin Li-Wei)
来源出版物: ACTA PHYSICA SINICA 卷: 67 期: 1 文献号: 014209 DOI: 10.7498/aps.67.20171729 出版年: JAN 5 2018
摘要: High resolution and high sensitive low light level imaging sensors are crucial in many applications such as astronomical observation, high energy physics, night vision and remote sensing. The electron bombarded complementary metal oxide semiconductor (EBCMOS) sensor is a novel imager in which very high gain can be produced by hitting the semiconductor with high voltage without any noise generation. In addition, it can process high-definition image with kHz frame rate. These advatages make the EBCMOS an ideal device for ultrafast single-photon imgaing. In this article, we present an EBCMOS sensor working in the ultraviolet range by combing the technology of vacuum photocathode and back illuminated CMOS together. This EBCMOS sensor can realize very high resolution in 40 mlx light illumination environment. The achieved spatial resolution is 25 lp/mm (line paris per millimeter) when the electric field intensity is 5000 V/mm. The liner relation between electric field intensity and the resolution indicates that much better perofromance can be achieved if the electric field intensity increases to a much higher value. The EBCMOS sensor developed in this paper can be directly applied to UV weak light detection, moreover it will provide a good reference for further developing the visible and near infrared sensitive EBCMOS sensors.
入藏号: WOS:000425271100016
ISSN: 1000-3290
________________________________________
第 277 条,共 322 条
标题: Review on optofluidic microreactors for artificial photosynthesis
作者: Huang, XW (Huang, Xiaowen); Wang, JC (Wang, Jianchun); Li, TH (Li, Tenghao); Wang, JM (Wang, Jianmei); Xu, M (Xu, Min); Yu, WX (Yu, Weixing); El Abed, A (El Abed, Abdel); Zhang, XM (Zhang, Xuming)
来源出版物: BEILSTEIN JOURNAL OF NANOTECHNOLOGY 卷: 9 页: 30-41 DOI: 10.3762/bjnano.9.5 出版年: JAN 4 2018
摘要: Artificial photosynthesis (APS) mimics natural photosynthesis (NPS) to store solar energy in chemical compounds for applications such as water splitting, CO2 fixation and coenzyme regeneration. NPS is naturally an optofluidic system since the cells (typical size 10 to 100 mu m) of green plants, algae, and cyanobacteria enable light capture, biochemical and enzymatic reactions and the related material transport in a microscale, aqueous environment. The long history of evolution has equipped NPS with the remarkable merits of a large surface-area-to-volume ratio, fast small molecule diffusion and precise control of mass transfer. APS is expected to share many of the same advantages of NPS and could even provide more functionality if optofluidic technology is introduced. Recently, many studies have reported on optofluidic APS systems, but there is still a lack of an in-depth review. This article will start with a brief introduction of the physical mechanisms and will then review recent progresses in water splitting, CO2 fixation and coenzyme regeneration in optofluidic APS systems, followed by discussions on pending problems for real applications.
入藏号: WOS:000455311600001
PubMed ID: 29379698
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Weixing         G-3658-2012         0000-0002-3216-526X
Zhang, Xuming         K-4900-2013         0000-0002-9326-5547

ISSN: 2190-4286
________________________________________
第 278 条,共 322 条
标题: Punishment diminishes the benefits of network reciprocity in social dilemma experiments
作者: Li, XL (Li, Xuelong); Jusup, M (Jusup, Marko); Wang, Z (Wang, Zhen); Li, HJ (Li, Huijia); Shi, L (Shi, Lei); Podobnik, B (Podobnik, Boris); Stanley, HE (Stanley, H. Eugene); Havlin, S (Havlin, Shlomo); Boccaletti, S (Boccaletti, Stefano)
来源出版物: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 卷: 115 期: 1 页: 30-35 DOI: 10.1073/pnas.1707505115 出版年: JAN 2 2018
摘要: Network reciprocity has been widely advertised in theoretical studies as one of the basic cooperation-promoting mechanisms, but experimental evidence favoring this type of reciprocity was published only recently. When organized in an unchanging network of social contacts, human subjects cooperate provided the following strict condition is satisfied: The benefit of cooperation must outweigh the total cost of cooperating with all neighbors. In an attempt to relax this condition, we perform social dilemma experiments wherein network reciprocity is aided with another theoretically hypothesized cooperation-promoting mechanism-costly punishment. The results reveal how networks promote and stabilize cooperation. This stabilizing effect is stronger in a smaller-size neighborhood, as expected from theory and experiments. Contrary to expectations, punishment diminishes the benefits of network reciprocity by lowering assortment, payoff per round, and award for cooperative behavior. This diminishing effect is stronger in a larger-size neighborhood. An immediate implication is that the psychological effects of enduring punishment override the rational response anticipated in quantitative models of cooperation in networks.
入藏号: WOS:000419128700022
PubMed ID: 29259113
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Jusup, Marko         S-8567-2018         0000-0002-0777-0425
Li, Xuelong         Z-3785-2019         
Wang, Zhen         H-5017-2011         0000-0002-8182-2852
Podobnik, Boris         S-4583-2018         0000-0003-4270-1756
Li, Xuelong                  0000-0002-0019-4197
Stanley, H.                  0000-0003-2800-4495
Li, Hui-Jia                  0000-0003-1000-717X

ISSN: 0027-8424
________________________________________
第 279 条,共 322 条
标题: Principle of a two-output-difference interferometer for removing the most important interference distortions
作者: Yang, QH (Yang, Qinghua); Liu, LX (Liu, Lixin); Lv, P (Lv, Pei)
来源出版物: JOURNAL OF MODERN OPTICS 卷: 65 期: 19 页: 2200-2208 DOI: 10.1080/09500340.2018.1506054 出版年: 2018
摘要: This paper presents a two-output-difference interferometer for removing the most important interference distortions caused by nonlinear detectors. These distortions can be removed not only because the resulting interferogram is composed of the difference between the signals of the two detectors, but also because the modulated signals at each output have the same amplitude and opposite phases. Due to the use of two corner-cube mirrors fixed as a single moving element, the tilt and shearing problem will disappear. The effect of the corner-cube mirror deviation angle and the plane mirror tilt angle are investigated in detail, and the formulas of their tolerance are derived by means of modulation depth and phase error. The advantage of the interferometer enables it to be suitable for Fourier transform spectrometers.
入藏号: WOS:000457329300005
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yang, Qinghua                  0000-0003-4679-1621

ISSN: 0950-0340
eISSN: 1362-3044
________________________________________
第 280 条,共 322 条
标题: Machine Learning in Ultrasound Computer-Aided Diagnostic Systems: A Survey
作者: Huang, QH (Huang, Qinghua); Zhang, F (Zhang, Fan); Li, XL (Li, Xuelong)
来源出版物: BIOMED RESEARCH INTERNATIONAL 文献号: 5137904 DOI: 10.1155/2018/5137904 出版年: 2018
摘要: The ultrasound imaging is one of the most common schemes to detect diseases in the clinical practice. There are many advantages of ultrasound imaging such as safety, convenience, and low cost. However, reading ultrasound imaging is not easy. To support the diagnosis of clinicians and reduce the load of doctors, many ultrasound computer-aided diagnosis (CAD) systems are proposed. In recent years, the success of deep learning in the image classification and segmentation led to more and more scholars realizing the potential of performance improvement brought by utilizing the deep learning in the ultrasound CAD system. This paper summarized the research which focuses on the ultrasound CAD system utilizingmachine learning technology in recent years. This study divided the ultrasound CAD system into two categories. One is the traditional ultrasound CAD system which employed the manmade feature and the other is the deep learning ultrasound CAD system. The major feature and the classifier employed by the traditional ultrasound CAD system are introduced. As for the deep learning ultrasound CAD, newest applications are summarized. This paper will be useful for researchers who focus on the ultrasound CAD system.
入藏号: WOS:000426555700001
PubMed ID: 29687000
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2314-6133
eISSN: 2314-6141
________________________________________
第 281 条,共 322 条
标题: Crystallization and Dielectric Properties of Transparent Na2O-Nb2O5-SiO2 Based Glass-Ceramics
作者: Hu, B (Hu, Bin); Wang, PF (Wang, Pengfei); He, QL (He, Quanlong); Yu, TL (Yu, Tianlai); Lu, M (Lu, Min)
来源出版物: ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY 卷: 7 期: 6 页: N81-N85 DOI: 10.1149/2.0091806jss 出版年: 2018
摘要: Na2O-Nb2O5-SiO2 based glass-ceramics with and without ZrO2/TiO2 were prepared by controlled crystallization, and their crystallization properties under different heat-treatment temperatures were characterized by differential scanning calorimetry, X-Ray Diffraction (XRD) and morphology observation. The XRD results indicated the presence of NaNbO3 with perovskite structure as the major crystalline phase. The introduction of ZrO2 contributed to the stabilization of the Na2O-Nb2O5-SiO2 basic glass, and thus improved their crystallization. Moreover, changes of the dielectric constant of the glass-ceramics with the frequency and measuring temperature were mainly studied. In details, the maximum dielectric constant reached 136.9 (@1000 KHz, 25 degrees C), and the rate of change with temperature is as small as about -0.0302/degrees C. The crystalline glass remains transparent in the range of 400-800 nm, and the transmittance is above 70% for the 2 mm thick sample. (C) 2018 The Electrochemical Society.
入藏号: WOS:000440836000005
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Pengfei, Wang                  0000-0002-5285-9832

ISSN: 2162-8769
________________________________________
第 282 条,共 322 条
标题: Influence of ZnO and Heat Treatment Process on the Physical and Optical Properties of MgO-Al2O3-SiO2 Glass-Ceramics
作者: Hu, B (Hu, Bin); Yuan, BP (Yuan, Baoping); Wang, PF (Wang, Pengfei); Wang, J (Wang, Jing); Han, JJ (Han, Jianjun); Lu, M (Lu, Min)
来源出版物: ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY 卷: 7 期: 4 页: N42-N45 DOI: 10.1149/2.0151804jss 出版年: 2018
摘要: The influences of adding ZnO and the use of specific heat-treatment schedules on MgO-Al2O3-SiO2 (MAS) glass-ceramic properties including crystallization, micromorphology, optical transmittance and Vickers-hardness were investigated. The XRD analysis proved that MgAl2O4 and Al2ZnO4 spinel are the major crystalline phases formed in the studied MgO-Al2O3-SiO2-ZnO (MASZ) glass ceramics. The addition of ZnO facilitated the crystallization of the MAS glass and resulted in a uniform and compact microstructure. The homogeneous distribution of microcrystals with average grain size less than 100 nm in the MASZ glass-ceramics contributed to the improvement of the corresponding transmittance in the visible range. In addition, the orthogonal heat-treatment experiment indicated that the crystallization time and nucleation time have a dominant effect on the microhardness of glass-ceramics, followed by decreasing effects of crystallization temperature and nucleation temperature. (C) 2018 The Electrochemical Society.
入藏号: WOS:000430973200019
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Pengfei, Wang                  0000-0002-5285-9832

ISSN: 2162-8769
________________________________________
第 283 条,共 322 条
标题: Auxiliary Loss Multimodal GRU Model in Audio-Visual Speech Recognition
作者: Yuan, Y (Yuan, Yuan); Tian, CL (Tian, Chunlin); Lu, XQ (Lu, Xiaoqiang)
来源出版物: IEEE ACCESS 卷: 6 页: 5573-5583 DOI: 10.1109/ACCESS.2018.2796118 出版年: 2018
摘要: Audio-visual speech recognition (AVSR) utilizes both audio and video modalities for the robust automatic speech recognition. Most deep neural network (DNN) has achieved promising performances in AVSR owing to its generalized and nonlinear mapping ability. However, these DNN models have two main disadvantages: 1) the first disadvantage is that most models alleviate the AVSR problems neglecting the fact that the frames are correlated; and 2) the second disadvantage is the feature learned by the mentioned models is not credible. This is because the joint representation learned by the fusion fails to consider the specific information of categories, and the discriminative information is sparse, while the noise, reverberation, irrelevant image objection, and background are redundancy. Aiming at relieving these disadvantages, we propose the auxiliary loss multimodal GRU (alm-GRU) model including three parts: feature extraction, data augmentation, and fusion & recognition. The feature extraction and data augmentation are a complete effective solution for the processing raw complete video and training, and precondition for later core part: fusion & recognition using alm-GRU equipped with a novel loss which is an end-to-end network combining both fusion and recognition, furthermore considering the modal and temporal information. The experiments show the superiority of our model and necessity of the data augmentation and generative component in the benchmark data sets.
入藏号: WOS:000426304300001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Lu, Xiaoqiang                  0000-0002-7037-5188

ISSN: 2169-3536
________________________________________
第 284 条,共 322 条
标题: Harmonious Genetic Clustering
作者: Huang, FL (Huang, Faliang); Li, XL (Li, Xuelong); Zhang, SC (Zhang, Shichao); Zhang, JL (Zhang, Jilian)
来源出版物: IEEE TRANSACTIONS ON CYBERNETICS 卷: 48 期: 1 页: 199-214 DOI: 10.1109/TCYB.2016.2628722 出版年: JAN 2018
摘要: To automatically determine the number of clusters and generate more quality clusters while clustering data samples, we propose a harmonious genetic clustering algorithm, named HGCA, which is based on harmonious mating in eugenic theory. Different from extant genetic clustering methods that only use fitness, HGCA aims to select the most suitable mate for each chromosome and takes into account chromosomes gender, age, and fitness when computing mating attractiveness. To avoid illegal mating, we design three mating prohibition schemes, i.e., no mating prohibition, mating prohibition based on lineal relativeness, and mating prohibition based on collateral relativeness, and three mating strategies, i.e., greedy eugenics-based mating strategy, eugenics-based mating strategy based on weighted bipartite matching, and eugenics-based mating strategy based on unweighted bipartite matching, for harmonious mating. In particular, a novel single-point crossover operator called variable-length-and-gender-balance crossover is devised to probabilistically guarantee the balance between population gender ratio and dynamics of chromosome lengths. We evaluate the proposed approach on real-life and artificial datasets, and the results show that our algorithm outperforms existing genetic clustering methods in terms of robustness, efficiency, and effectiveness.
入藏号: WOS:000418291400017
PubMed ID: 28103198
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 2168-2267
eISSN: 2168-2275
________________________________________
第 285 条,共 322 条
标题: Hierarchical Recurrent Neural Hashing for Image Retrieval With Hierarchical Convolutional Features
作者: Lu, XQ (Lu, Xiaoqiang); Chen, YX (Chen, Yaxiong); Li, XL (Li, Xuelong)
来源出版物: IEEE TRANSACTIONS ON IMAGE PROCESSING 卷: 27 期: 1 页: 106-120 DOI: 10.1109/TIP.2017.2755766 出版年: JAN 2018
摘要: Hashing has been an important and effective technology in image retrieval due to its computational efficiency and fast search speed. The traditional hashing methods usually learn hash functions to obtain binary codes by exploiting hand-crafted features, which cannot optimally represent the information of the sample. Recently, deep learning methods can achieve better performance, since deep learning architectures can learn more effective image representation features. However, these methods only use semantic features to generate hash codes by shallow projection but ignore texture details. In this paper, we proposed a novel hashing method, namely hierarchical recurrent neural hashing (HRNH), to exploit hierarchical recurrent neural network to generate effective hash codes. There are three contributions of this paper. First, a deep hashing method is proposed to extensively exploit both spatial details and semantic information, in which, we leverage hierarchical convolutional features to construct image pyramid representation. Second, our proposed deep network can exploit directly convolutional feature maps as input to preserve the spatial structure of convolutional feature maps. Finally, we propose a new loss function that considers the quantization error of binarizing the continuous embeddings into the discrete binary codes, and simultaneously maintains the semantic similarity and balanceable property of hash codes. Experimental results on four widely used data sets demonstrate that the proposed HRNH can achieve superior performance over other state-of-the-art hashing methods.
入藏号: WOS:000413256300008
PubMed ID: 28952940
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Xuelong         Z-3785-2019         
Lu, Xiaoqiang                  0000-0002-7037-5188
Chen, Yaxiong                  0000-0002-2903-6723
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1057-7149
eISSN: 1941-0042
________________________________________
第 286 条,共 322 条
标题: Small target detection based on reweighted infrared patch-image model
作者: Guo, J (Guo, Jun); Wu, YQ (Wu, Yiquan); Dai, YM (Dai, Yimian)
来源出版物: IET IMAGE PROCESSING 卷: 12 期: 1 页: 70-79 DOI: 10.1049/iet-ipr.2017.0353 出版年: JAN 2018
摘要: To further improve the effect of infrared small target detection, a reweighted infrared patch-image model is proposed. First, the authors point out that the nuclear norm in the infrared patch-image model could easily leave some sparse background edges in the target patch-image, leading to an inaccurate background estimation. Then, to overcome this defect, the reweighted nuclear norm is adopted to constrain the background patch-image, which could preserve the background edges better. Considering that some non-target sparse points could not be suppressed by only using l(1) norm, the authors introduce the reweighted l(1) norm to further enhance the sparsity of target image. Finally, the proposed model is formulated as a reweighted robust principal component analysis problem and solved by the inexact augmented Lagrangian multiplier method. Extensive experiments show that the proposed model outperforms the other six competitive methods in suppressing background clutter and detecting target.
入藏号: WOS:000419403600008
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Dai, Yimian         W-2780-2019         

ISSN: 1751-9659
eISSN: 1751-9667
________________________________________
第 287 条,共 322 条
标题: Broadband wavelength conversion in hydrogenated amorphous silicon waveguide with silicon nitride layer
作者: Wang, J (Wang, Jiang); Li, YF (Li, Yongfang); Wang, ZL (Wang, Zhaolu); Han, J (Han, Jing); Huang, N (Huang, Nan); Liu, HJ (Liu, Hongjun)
来源出版物: JOURNAL OF MODERN OPTICS 卷: 65 期: 1 页: 1-7 DOI: 10.1080/09500340.2017.1366565 出版年: 2018
摘要: Broadband wavelength conversion based on degenerate four-wave mixing is theoretically investigated in a hydrogenated amorphous silicon (a-Si:H) waveguide with silicon nitride inter-cladding layer (a-Si:HN). We have found that enhancement of the non-linear effect of a-Si:H waveguide nitride intermediate layer facilitates broadband wavelength conversion. Conversion bandwidth of 490 nm and conversion efficiency of 11.4 dB were achieved in a numerical simulation of a 4 mm-long a-Si:HN waveguide under 1.55 mu m continuous wave pumping. This broadband continuous-wave wavelength converter has potential applications in photonic networks, a type of readily manufactured low-cost highly integrated optical circuits.
入藏号: WOS:000426633600001
ISSN: 0950-0340
eISSN: 1362-3044
________________________________________
第 288 条,共 322 条
标题: Theoretical analysis on power stability and switch time of the non-mechanical beam steering using liquid crystal optical phased array
作者: Wang, XR (Wang, Xiangru); Wu, L (Wu, Liang); He, XX (He, Xiaoxian); Huang, XN (Huang, Xinning); Tan, QG (Tan, Qinggui)
来源出版物: LIQUID CRYSTALS 卷: 45 期: 10 页: 1477-1486 DOI: 10.1080/02678292.2018.1448474 出版年: 2018
摘要: Focusing on the coherent optics of phased array, a dynamic theoretical model is built to analyse the process of laser beam steering using the device of liquid crystal optical phased array. Based on the dynamics of electrical field induced liquid crystal molecule rotation and the mechanism of phased control non-mechanical steering, switching time is redefined according to two curves representing receiving power on the current direction and targeting direction. Meanwhile, including the far field distribution, power stability and pointing direction, two cases with large steering step and tiny steering step are evaluated. The steering time between two angles is minished to be less than the switch-off decay time. In addition, the instability on the process of beam steering is obvious although the steering step is only half of beam width. To overcome this instability, tinier steering step is suggested although it is also limited by the driving algorithm and driving circuits.
入藏号: WOS:000439980100008
ISSN: 0267-8292
eISSN: 1366-5855
________________________________________
第 289 条,共 322 条
标题: Joint Method of Interference Suppression and Super-Resolution for Chinese Characters Image with Interference
作者: Jiang, B (Jiang, Bo); Hu, W (Hu, Wei); Liang, J (Liang, Jian); Zhang, SX (Zhang, Shouxu); Ma, XL (Ma, Xiaolei); Zhou, Y (Zhou, Yan); Niu, JP (Niu, Jinping); Chen, XX (Chen, Xiaoxuan)
来源出版物: MATHEMATICAL PROBLEMS IN ENGINEERING 文献号: 4203121 DOI: 10.1155/2018/4203121 出版年: 2018
摘要: As Chinese characters image often has insufficient photography illumination, or underlines under characters, or low resolution, a joint method of interference suppression and super-resolution for Chinese characters image with interference is proposed. In the stage of interference suppression preprocessing, the technology of image layer separation is used to decompose Chinese characters image into the illumination layer and reflectance layer at first, and reflectance layer that contains the essential property of input image is retained consequently. Then the reflectance layer is decomposed into four coefficient subimages by wavelet transform, and image smoothing via L-0 gradient minimization with different scale factors is adopted to these different coefficient subimages. Subsequently, by a simple background processing and image filtering, the image preprocessing for Chinese characters image with interference is ultimately completed. In the stage of image super-resolution, due to acquisition limitation of a large number of high-resolution Chinese characters images, we adopt neighbor embedding super-resolution method for its advantage of greatly reducing the scale of training set. In the key feature vector of Chinese characters image, the weights of horizontal and vertical stroke features are strengthened; meanwhile, the other stroke features of Chinese characters are also considered. Ultimately, a super-resolution method more suitable for Chinese characters image is proposed. Experimental results show that our method of interference suppression has the superiority for Chinese characters images with aforementioned interference, and our optimized super-resolution method has better performance for test Chinese characters images than bicubic interpolation method and three classical super-resolution methods.
入藏号: WOS:000449192300001
ISSN: 1024-123X
eISSN: 1563-5147
________________________________________
第 290 条,共 322 条
标题: Generation of vortex beams with multi topological charges, high purity and operating on broadband using a simple silver metasurface
作者: Zhang, XD (Zhang, Xiaodong); Kong, DP (Kong, Depeng); Li, SQ (Li, Siqi); Wang, LL (Wang, Lili)
来源出版物: OPTIK 卷: 175 页: 319-327 DOI: 10.1016/j.ijleo.2018.09.003 出版年: 2018
摘要: We propose a simple approach to generate vortex beam based on silver metasurface under the incidence of circularly polarized light. The topological charge and purity of result beam is from -4 to 4 and more than 95% respectively, furthermore, it can operate on broadband (800 similar to 1800 nm) including telecom wavelengths. The designed metasurface is composed of ten concentric rings, where each ring is composed of sub-wavelength rectangular apertures with circular array distribution. These rectangular apertures act as localized space-variant linear polarizers and space-variant polarization manipulation can introduce Pancharatnam-Berry (PB) phase. Simulation results show that this design is logically coincidence. The designed metasurface has the advantage of high fabrication tolerance and may be a potential candidate in future integrated optical communication system.
入藏号: WOS:000449312200041
ISSN: 0030-4026
________________________________________
第 291 条,共 322 条
标题: Hybrid high energy femtosecond laser system based on Yb:YAG single crystal fiber amplifier
作者: Li, F (Li, Feng); Yang, Z (Yang, Zhi); Wang, YS (Wang, Yishan); Lv, ZG (Lv, Zhiguo); Li, QL (Li, Qianglong); Yang, XJ (Yang, Xiaojun); Wang, XL (Wang, Xianglin); Hu, XH (Hu, Xiaohong); Zhao, W (Zhao, Wei)
来源出版物: OPTIK 卷: 156 页: 155-160 DOI: 10.1016/j.ijleo.2017.10.158 出版年: 2018
摘要: A hybrid high energy femtosecond laser system based on Yb:YAG single crystal fiber amplifier is experimentally studied. Due to the low nonlinearity and high gain of the Yb:YAG single crystal fiber, laser pulses with high energy of 146 mu J at the repetition of 100KHz are obtained. The beam quality of 1.233 in the horizontal direction and 1.239 in the vertical direction is detected. After compression, pulses with the duration of 859 fs and energy as high as 63.5 mu J are achieved at 100 kHz repetition rate in a compact size, this compact and simple laser system will find various applications in ultrafast laser micro-machining. (C) 2017 Elsevier GmbH. All rights reserved.
入藏号: WOS:000424311500021
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
qianglong, li         V-6278-2019         

ISSN: 0030-4026
________________________________________
第 292 条,共 322 条
标题: Spectrum reconstruction in interference spectrometer based on sparse Fourier transform
作者: Zhang, WK (Zhang, Weikang); Wen, DS (Wen, Desheng); Song, ZX (Song, Zongxi)
来源出版物: OPTIK 卷: 154 页: 157-164 DOI: 10.1016/j.ijleo.2017.09.004 出版年: 2018
摘要: The algorithm of SFT (sparse Fourier transform) is firstly used for monochromatic light spectrum reconstruction in this paper. Due to the increasing amount of interference data, the operation efficiency of traditional algorithms is not satisfied with the demand of technology. We take advantage of SFT to achieve the goal of lower algorithm complexity and fewer operation time, instead of FFT (Fast Fourier Transform). In addition, two methods of the modern spectrum estimation, AR (Auto-Regressive) model and MUSIC (Multiple Signal Classification), which are considered as high resolution spectrum estimation algorithms, are used for discussion and comparison. The experiment result shows that the SFT gets excellent performance in runtime. (C) 2017 Elsevier GmbH. All rights reserved.
入藏号: WOS:000418731200020
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zhang, Weikang                  0000-0003-2279-3294

ISSN: 0030-4026
________________________________________
第 293 条,共 322 条
标题: Structured dictionary learning for abnormal event detection in crowded scenes
作者: Yuan, Y (Yuan, Yuan); Feng, YC (Feng, Yachuang); Lu, XQ (Lu, Xiaoqiang)
来源出版物: PATTERN RECOGNITION 卷: 73 页: 99-110 DOI: 10.1016/j.patcog.2017.08.001 出版年: JAN 2018
摘要: Abnormal event detection is now a widely concerned research topic, especially for crowded scenes. In recent years, many dictionary learning algorithms have been developed to learn normal event regularities, and have presented promising performance for abnormal event detection. However, they seldom consider the structural information, which plays important roles in many computer vision tasks, such as image denoising and segmentation. In this paper, structural information is explored within a sparse representation framework. On the one hand, we introduce a new concept named reference event, which indicates the potential event patterns in normal video events. Compared with abnormal events, normal ones are more likely to approximate these reference events. On the other hand, a smoothness regularization is constructed to describe the relationships among video events. The relationships consist of both similarities in the feature space and relative positions in the video sequences. In this case, video events related to each other are more likely to possess similar representations. The structured dictionary and sparse representation coefficients are optimized through an iterative updating strategy. In the testing phase, abnormal events are identified as samples which cannot be well represented using the learned dictionary. Extensive experiments and comparisons with state-of-the-art algorithms have been conducted to prove the effectiveness of the proposed algorithm. (C) 2017 Elsevier Ltd. All rights reserved.
入藏号: WOS:000412958800008
ISSN: 0031-3203
eISSN: 1873-5142
________________________________________
第 294 条,共 322 条
标题: Two-stage local constrained sparse coding for fine-grained visual categorization
作者: Guo, LH (Guo, Lihua); Guo, CG (Guo, Chenggang); Li, L (Li, Lei); Huang, QH (Huang, Qinghua); Li, YS (Li, Yanshan); Li, XL (Li, Xuelong)
来源出版物: SCIENCE CHINA-INFORMATION SCIENCES 卷: 61 期: 1 文献号: 018104 DOI: 10.1007/s11432-017-9158-x 出版年: JAN 2018
入藏号: WOS:000416050500003
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Huang, Qinghua         L-8708-2019         0000-0003-1080-6940
Li, Xuelong         Z-3785-2019         
Li, Xuelong                  0000-0002-0019-4197

ISSN: 1674-733X
eISSN: 1869-1919
________________________________________
第 295 条,共 322 条
标题: Label-free glucose biosensor based on enzymatic graphene oxide-functionalized tilted fiber grating
作者: Jiang, BQ (Jiang, Biqiang); Zhou, KM (Zhou, Kaiming); Wang, CL (Wang, Changle); Sun, QZ (Sun, Qizhen); Yin, GL (Yin, Guolu); Tai, ZJ (Tai, Zhijun); Wilson, KR (Wilson, Karen); Zhao, JL (Zhao, Jianlin); Zhang, L (Zhang, Lin)
来源出版物: SENSORS AND ACTUATORS B-CHEMICAL 卷: 254 页: 1033-1039 DOI: 10.1016/j.snb.2017.07.109 出版年: JAN 2018
摘要: A label-free biosensor based on graphene oxide (GO) and glucose oxidase (GOD) functionalized tilted fiber grating (TFG) with large tilted angle is proposed for low concentration glucose detection. Taking advantages of sufficient binding sites of the GO with oxygen-containing groups, the enzymes (GOD) are covalently immobilized onto GO-deposited TFG via 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxyl succinimide cross-liner. Surface characterizations with optical microscopy, scanning electron microscopy, Raman and infrared spectroscopy provide detailed assessments and evidences about the homogeneity of GO deposition and the effectiveness of enzyme modification. Through the specific catalysis reaction of GOD on the glucose, a considerable refractive index change in local microenvironment around the TFG results in the resonant wavelength shifts of cladding modes. The detection results of the low-concentration glucose demonstrate that the resonant wavelength has a linear response to the glucose concentration in the range of 0-8 mM with a response coefficient of 0.24 nm/mM, showing an enhanced sensitivity and bio-selectivity compared with the pristine TFG. The miniaturized size and remote label-free sensing capacity of the proposed device permit a multitude of opportunities for single-point measurement in harsh conditions and hard-to-reach spaces, presenting a promising candidate for label-free glucose detection for disease diagnosis, pharmaceutical research and bioengineering applications. Crown Copyright (C) 2017 Published by Elsevier B.V. All rights reserved.
入藏号: WOS:000413308000125
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Wilson, Karen         A-1061-2009         0000-0003-4873-708X
Yin, Guolu         D-3664-2014         0000-0002-8004-4198

ISSN: 0925-4005
________________________________________
第 296 条,共 322 条
标题: Stokes polarimeter for the measurement of full linearly Stokes parameters with immunity to Gaussian and Poisson noise
作者: Li, SY (Li, Siyuan); Quan, NC (Quan, Naicheng); Zhang, CM (Zhang, Chunmin); Mu, TK (Mu, Tingkui); Hu, BL (Hu, Bingliang)
来源出版物: OPTIK 卷: 175 页: 8-16 DOI: 10.1016/j.ijleo.2018.08.054 出版年: 2018
摘要: The optimization of Stokes polarimeter to determine the full linearly Stokes parameters in the presence of additive Gaussian noise and signal-dependent Poisson shot noise is addressed. The measurement matrix to minimize the total measurement variance on the full linearly Stokes parameters is optimized. Compared with the previous measurement matrix, the optimal measurement matrix proposed in this paper can effectively improve the measurement precision of the full linearly Stokes parameters statistically. In addition, a practical configuration of Stokes polarimeter is optimized by a cost function to generate the optimal measurement matrix. For the Stokes polarimeter composed by a variable retarder and fixed polarizer, the optimal measurement matrix can be easily generated by a 179.28 degrees retardation with a pair of azimuths +/- 78.84 degrees and a 179.64 degrees retardation with a pair of azimuths +/- 33.84 degrees.
入藏号: WOS:000449312200002
ISSN: 0030-4026
________________________________________
第 297 条,共 322 条
标题: Hyperspectral image classification based on adaptive segmentation
作者: Wu, YH (Wu, Yinhua); Hu, BL (Hu, Bingliang); Gao, XH (Gao, Xiaohui); Wei, RY (Wei, Ruyi)
来源出版物: OPTIK 卷: 172 页: 612-621 DOI: 10.1016/j.ijleo.2018.07.058 出版年: 2018
摘要: Object-based hyperspectral image classification (OBHIC) converts the basic unit from 'pixel' to 'object' by image segmentation, in order to take advantage of the spatial distribution law of geographical substances, as well as increase classification performances. However, it involves the problem of scale selection, i.e. the segmentation parameters are set manually by empirical values. In this paper, a novel OBHIC algorithm based on adaptive segmentation is proposed. Here, hyperspectral images (HSIs) are first segmented through a new segmentation scheme with constraint ability, and the thresholds for segmentation are calculated adaptively by utilizing training samples. And then K-nearest neighbor algorithm (KNN) is applied to classify the centers of each region after segmentation. In addition, based on the semisupervised idea, semi-known samples are obtained to further improve the classification performance. Experimental results are presented on two HSI datasets. For different HSIs, the adaptive thresholds calculated are consistent with empirical ones, and the developed classification algorithm has achieved good classification results, thus demonstrating strong robustness of the algorithm. For the HSI Indian Pines from AVIRIS sensor, the Overall Accuracy (OA) and kappa are 95.13% and 0.9444 respectively with 10% training samples, and for the HSI Pavia University from ROSIS sensor, the OA and kappa are 95.52% and 0.9416 respectively with 2% training samples. And good classification performance is still maintained for small number of training samples.
入藏号: WOS:000445714700076
ISSN: 0030-4026
________________________________________
第 298 条,共 322 条
标题: Calibration of Photoelectric Response Characteristics of a Scientific Grade Charge-coupled Device (CCD) Camera Based on Wedge Interference
作者: Lin, H (Lin, H.); Da, ZS (Da, Z-S.)
来源出版物: LASERS IN ENGINEERING 卷: 41 期: 1-3 页: 129-137 出版年: 2018
摘要: In experimental studies of inertial confinement fusion (ICF). scientific grade charge-coupled device (CCD) cameras are widely used for temporal and spatial investigations of the physical processes that occur during such experiments, such as shock waves. The performance of such a camera is directly related to its accuracy and credibility of measurement, so it is important to calibrate the photoelectric response characteristics of a scientific grade CCD camera before using it. The traditional system and process used for calibration is complex, involving measurement errors that can adversely affect the accuracy and confidence of calibration. This paper proposes a new method that relies on wedge interference is used images captured by the CCD camera to be calibrated and the calculated laser intensity distribution due to interference to obtain the photoelectric response characteristics of the camera via data processing. This method not only ensures realistic and reliable calibration results but also is simple and fast, providing a basis for obtaining accurate data in ICF experiments.
入藏号: WOS:000445401900008
ISSN: 0898-1507
eISSN: 1029-029X
________________________________________
第 299 条,共 322 条
标题: Microhole Drilling in TiC Ceramic with a Femtosecond Pulsed Laser
作者: Zhang, JZ (Zhang, J. Z.); Liu, YS (Liu, Y. S.); Wang, YQ (Wang, Y. Q.); Zhang, Y (Zhang, Y.); Yang, XJ (Yang, X. J.)
来源出版物: LASERS IN ENGINEERING 卷: 41 期: 4-6 页: 359-371 出版年: 2018
摘要: A femtosecond (fs) pulsed laser was employed to drill microholes in TiC ceramic. The Morphologies of microholes drilled at different assisted gas pressures and laser feeding speeds were investigated. Chemical compositions and chemical bonds of laser treated debris and untreated specimen were analysed. The mechanism of interaction between the femtosecond laser and the TiC ceramic was discussed. The results indicated that the assisted gas pressure had a greater effect on the morphologies of microholes, compared with the feeding speed. The entrance diameter of microholes was smaller than the exit diameter. The entrance roundness was more perfect than the exit roundness, and the entrance roundness decreased slightly with increasing gas pressure and feeding speed. Higher feeding speed was unfavourable to the morphologies of microholes. Ti, C and O were detected in laser treated debris. X-ray photoelectron spectroscopy (XPS) investigation showed that the C-Ti bond was broken and Ti2O3 and TiO2 were formed during drilling.
入藏号: WOS:000445529800010
ISSN: 0898-1507
eISSN: 1029-029X
________________________________________
第 300 条,共 322 条
标题: A Robust Sparse Representation Based Pattern Recognition Approach for Myoelectric Control
作者: Geng, YJ (Geng, Yanjuan); Ouyang, Y (Ouyang, Yatao); Samuel, OW (Samuel, Oluwarotimi Williams); Chen, S (Chen, Shixiong); Lu, X (Lu, Xiaoqiang); Lin, C (Lin, Chuang); Li, G (Li, Guanglin)
来源出版物: IEEE ACCESS 卷: 6 页: 38326-38335 DOI: 10.1109/ACCESS.2018.2851282 出版年: 2018
摘要: Interferences in the form of white Gaussian noise (WGN) are inevitable during long-term electromyogram (EMG) recordings. Even with the aid of advanced signal denoising techniques, such an intermittent interference is hardly detected and attenuated in the practical use of EMG-driven control systems. Hence, a robust pattern recognition scheme that is invariant to noise contamination would potentially aid the realization of an efficient EMG-based pattern recognition (EMG-PR) control system. To this end, an EMG-PR scheme driven by sparse representation-based classification (SRC) algorithm and root mean square (rms) descriptor (RMS-SRC) is proposed in this paper. The accuracy and the robustness of the proposed scheme were investigated using the high-density surface EMG recordings from 12 traumatic brain-injured patients and 5 post-stroke survivors. For benchmark comparison, another three different feature sets and four pattern recognition algorithms were considered. The optimal pattern recognition schemes with respect to each feature-classifier combination were first selected in the absence of WGN contamination. Then, six levels of WGN with a signal-to-noise ratio (SNR) ranging from 5 to 30 dB were added into the EMG recordings, respectively, to mimic the different WGN interferences. Our result showed that the proposed RMS-SRC scheme could achieve a similar accuracy with the benchmark schemes in the presence of limited noise contamination (0-15 dB), and significantly outperformed the other schemes when the SNR of WGN increased (20-30 dB). More notably, the RMS-SRC scheme significantly outperformed the other pattern recognition schemes when the WGN existed in either training set or testing set only. The findings proved the comparative advantage of the proposed RMS-SRC pattern recognition scheme over the other currently used schemes in the myoelectric control. Thus, the proposed scheme would potentially facilitate the development of EMG-driven rehabilitation robots for accurate and dexterous assistive training for patients with neurological disorders.
入藏号: WOS:000440541700001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Samuel, Oluwarotimi Williams                  0000-0003-1945-1402

ISSN: 2169-3536


第 301 条,共 322 条
标题: Method of Image Quality Improvement for Atmospheric Turbulence Degradation Sequence Based on Graph Laplacian Filter and Nonrigid Registration
作者: Wu, J (Wu, Jing); Su, XQ (Su, Xiuqin)
来源出版物: MATHEMATICAL PROBLEMS IN ENGINEERING 文献号: 4970907 DOI: 10.1155/2018/4970907 出版年: 2018
摘要: It is challenging to restore a clear image from an atmospheric degraded sequence. The main reason for the image degradation is geometric distortion and blurring caused by turbulence. In this paper, we present a method to eliminate geometric distortion and blur and to recover a single high-quality image from the degraded sequence images. First, we use optical flow technology to register the sequence images, thereby suppressing the geometric deformation of each frame. Next, sequence images are summed by a temporal filter to obtain a single blurred image. Then, the graph Laplacian matrix is used as the cost function to construct the regularization term. The final clear image and point spread function are obtained by iteratively solving the problem. Experiments show that the method can effectively eliminate the distortion and blur, restore the image details, and significantly improve the image quality.
入藏号: WOS:000440427200001
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Su, Xiuqin                  0000-0002-6554-2762

ISSN: 1024-123X
eISSN: 1563-5147
________________________________________
第 302 条,共 322 条
标题: Modeling and Dynamic Control of a Class of Semibiomimetic Robotic Fish
作者: Zhang, SX (Zhang, Shouxu); Jiang, B (Jiang, Bo); Chen, XX (Chen, Xiaoxuan); Liang, J (Liang, Jian); Cui, P (Cui, Peng); Guo, XX (Guo, Xinxin)
来源出版物: COMPLEXITY 文献号: UNSP 4657235 DOI: 10.1155/2018/4657235 出版年: 2018
摘要: This paper proposes a new robotic fish which avoids the complex mechanical structure and reduces the model complexity comparing to the existing bioinspired robotic fish, giving rise to a semibiomimetic robotic fish. The generalized Lagrange equation is adopted to establish the dynamic model of the robotic fish. The controllability of the system is analyzed, upon which a trajectory tracking control algorithm is designed by using the feedback linearization technique. The simulation results show that the dynamic model adopted in this paper can achieve better control performance.
入藏号: WOS:000438804800001
ISSN: 1076-2787
eISSN: 1099-0526
________________________________________
第 303 条,共 322 条
标题: Trajectory and focal length of circular Airy beams in linear index potentials
作者: Long, XW (Long, Xuewen); Bai, J (Bai, Jing)
来源出版物: OPTIK 卷: 165 页: 356-361 DOI: 10.1016/j.ijleo.2018.03.134 出版年: 2018
摘要: In this paper, we investigate the propagation of abruptly autofocusing circular Airy beams (CAB) in linear index potential both analytically and numerically. Based on the initial field located far away from the center, we get the approximate analytical solutions to describe the trajectory and focal length of CAB in linear index potential. The modified focal length formula agrees well with numerical results for a wide range of the initial radius of CAB. Furthermore, the approximate method is also applicable to some dynamic potential varying along the propagation coordinate. (C) 2018 Elsevier GmbH. All rights reserved.
入藏号: WOS:000438326400044
ISSN: 0030-4026
________________________________________
第 304 条,共 322 条
标题: Angular position measurement of pulsars based on X-ray intensity correlation
作者: Su, T (Su Tong); Li, Y (Li Yao); Sheng, LZ (Sheng Lizhi); Qiang, PF (Qiang Pengfei); Zhao, BS (Zhao Baosheng)
来源出版物: OPTIK 卷: 161 页: 8-11 DOI: 10.1016/j.ijleo.2018.01.119 出版年: 2018
摘要: The positioning accuracy of the X-ray pulsar navigation depends on the angular position accuracy of the pulsars. Currently, long baseline interferometer technology provides 0.1 mas pulsar positioning accuracy, which is far away from the requirement of X-ray pulsar navigation. Using classical statistical optics, we studied the relationship between direct observation of the pulsar angular position and second-order correlation. As an application, we give a proposal to realize angular position measurement of pulsars based on X-ray intensity correlation. (C) 2018 Elsevier GmbH. All rights reserved.
入藏号: WOS:000429499100002
ISSN: 0030-4026
________________________________________
第 305 条,共 322 条
标题: Compact cross-dispersion device based on a prism and a plane transmission grating
作者: Yang, QH (Yang, Qinghua); Wang, WQ (Wang, Weiqiang)
来源出版物: JOURNAL OF MODERN OPTICS 卷: 65 期: 9 页: 1081-1089 DOI: 10.1080/09500340.2018.1424358 出版年: 2018
摘要: This paper presents a cross-dispersion prism-grating device using a plane transmission grating attached directly to a prism, which is different from traditional cross-dispersion grating-prism systems that are based on the reflection grating. Unlike conventional direct-vision grism or constant-dispersion grism in which both the prism and grating have the same dispersion direction, for this device the dispersion directions of the prism and grating are different. The analytical expressions for the cross-dispersion of this device are derived in detail and the formulas of the footprint of the dispersed spectra are given. The numerical results and ray-tracing simulations by ZEMAX are shown. The device provides a compact, small-sized and broadband cross-dispersion device used for the medium resolution spectrometer.
入藏号: WOS:000428269100007
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yang, Qinghua                  0000-0003-4679-1621

ISSN: 0950-0340
eISSN: 1362-3044
________________________________________
第 306 条,共 322 条
标题: CMOS compatible on-chip telecom-band to mid-infrared supercontinuum generation in dispersion-engineered reverse strip/slot hybrid Si3N4 waveguide
作者: Hui, ZQ (Hui, Zhanqiang); Zhang, LX (Zhang, Lingxuan); Zhang, WF (Zhang, Wenfu)
来源出版物: JOURNAL OF MODERN OPTICS 卷: 65 期: 1 页: 53-63 DOI: 10.1080/09500340.2017.1376718 出版年: 2018
摘要: A silicon nitride (Si3N4)-based reverse strip/slot hybrid waveguide with single vertical silica slot is proposed to acquire extremely low and flat chromatic dispersion profile. This is achieved by design and optimization of the geometrical structural parameters of the reverse hybrid waveguide. The flat dispersion varying between +/- 10 ps/(nm.km) is obtained over 610 nm bandwidth. Both the effective area and nonlinear coefficient of the waveguide across the entire spectral range of interest are investigated. This led to design of an on-chip supercontinuum (SC) source with -30 dB bandwidth of 2996 nm covering from 1.209 to 4.205 mu m. Furthermore, we discuss the output signal spectral and temporal characteristic as a function of the pump power. Our waveguide design offers a CMOS compatible, low-cost/high yield (no photolithography or lift-off processes are necessary) on-chip SC source for near- and mid-infrared nonlinear applications.
入藏号: WOS:000426633600007
ISSN: 0950-0340
eISSN: 1362-3044
________________________________________
第 307 条,共 322 条
标题: Backscatter spectra measurements of the two beams on the same cone on Shenguang-III laser facility
作者: Zha, WY (Zha, Weiyi); Yang, D (Yang, Dong); Xu, T (Xu, Tao); Liu, YG (Liu, Yonggang); Wang, F (Wang, Feng); Peng, XS (Peng, Xiaoshi); Li, YL (Li, Yulong); Wei, HY (Wei, Huiyue); Liu, XM (Liu, Xiangming); Mei, Y (Mei, Yu); Yan, YD (Yan, Yadong); He, JH (He, Junhua); Li, ZC (Li, Zhichao); Li, SW (Li, Sanwei); Jiang, XH (Jiang, Xiaohua); Guo, L (Guo, Liang); Xie, XF (Xie, Xufei); Pan, KQ (Pan, Kaiqiang); Liu, SY (Liu, Shenye); Jiang, S (Jiang, Shaoen); Zhang, BH (Zhang, Baohan); Ding, YK (Ding, Yongkun)
来源出版物: REVIEW OF SCIENTIFIC INSTRUMENTS 卷: 89 期: 1 文献号: 013501 DOI: 10.1063/1.5005501 出版年: JAN 2018
摘要: In laser driven hohlraums, laser beams on the same incident cone may have different beam and plasma conditions, causing beam-to-beam backscatter difference and subsequent azimuthal variations in the x-ray drive on the capsule. To elucidate the large variation of backscatter proportion from beam to beam in some gas-filled hohlraum shots on Shenguang-III, two 28.5 degrees beams have been measured with the Stimulated Raman Scattering (SRS) time-resolved spectra. A bifurcated fiber is used to sample two beams and then coupled to a spectrometer and streak camera combination to reduce the cost. The SRS spectra, characterized by a broad wavelength, were further corrected considering the temporal distortion and intensity modulation caused by components along the light path. This measurement will improve the understanding of the beam propagation inside the hohlraum and related laser plasma instabilities. Published by AIP Publishing.
入藏号: WOS:000424022400020
PubMed ID: 29390682
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yang, Dong                  0000-0003-4245-7204

ISSN: 0034-6748
eISSN: 1089-7623
________________________________________
第 308 条,共 322 条
标题: R&P: An Low-Cost Device-Free Activity Recognition for E-Health
作者: Li, LY (Li, Liyao); Bai, R (Bai, Rui); Xie, BB (Xie, Binbin); Peng, Y (Peng, Yao); Wang, AW (Wang, Anwen); Wang, W (Wang, Wei); Jiang, B (Jiang, Bo); Liang, J (Liang, Jian); Chen, XJ (Chen, Xiaojiang)
来源出版物: IEEE ACCESS 卷: 6 页: 81-90 DOI: 10.1109/ACCESS.2017.2749323 出版年: 2018
摘要: Activity recognition is important for taking care of patients and old men especially in e-Health. The activity recognition system without carrying any wearable devices is widely used in our daily life. Current methods employing uneconomical equipment or even dedicated devices lead to cost-inefficiency for large-scale deployments. This paper introduces R&P, a device-free activity recognition system only using cheap radio frequency identification devices (RFID) tags. Based on the analysis of RFID signals, we extract received signal strength fingerprints and phase fingerprints for each activity and synthesize these two kinds of fingerprints to accurately recognize activities. Moreover, we also modify the dynamic time warping (DTW) algorithm and propose T-DTW method to improve the recognition efficiency. We use commercial passive RFID hardware and verify R&Pin three different environments with different targets and six activities. The results demonstrate that our solution can recognize activities with an average accuracy of 87.9%.
入藏号: WOS:000424078700005
ISSN: 2169-3536
________________________________________
第 309 条,共 322 条
标题: Modified slanted-edge method for camera modulation transfer function measurement using nonuniform fast Fourier transform technique
作者: Duan, YX (Duan, Yaxuan); Xu, SB (Xu, Songbo); Yuan, SC (Yuan, Suochao); Chen, YQ (Chen, Yongquan); Li, HG (Li, Hongguang); Da, ZS (Da, Zhengshang); Gao, LM (Gao, Limin)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 1 文献号: 014103 DOI: 10.1117/1.OE.57.1.014103 出版年: JAN 2018
摘要: ISO 12233 slanted-edge method experiences errors using fast Fourier transform (FFT) in the camera modulation transfer function (MTF) measurement due to tilt angle errors in the knife-edge resulting in nonuniform sampling of the edge spread function (ESF). In order to resolve this problem, a modified slanted-edge method using nonuniform fast Fourier transform (NUFFT) for camera MTF measurement is proposed. Theoretical simulations for images with noise at a different nonuniform sampling rate of ESF are performed using the proposed modified slanted-edge method. It is shown that the proposed method successfully eliminates the error due to the nonuniform sampling of the ESF. An experimental setup for camera MTF measurement is established to verify the accuracy of the proposed method. The experiment results show that under different nonuniform sampling rates of ESF, the proposed modified slanted-edge method has improved accuracy for the camera MTF measurement compared to the ISO 12233 slanted-edge method. (C) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
入藏号: WOS:000424272600036
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 310 条,共 322 条
标题: Optical planar waveguides in photo-thermal-refractive glasses fabricated by single- or double-energy carbon ion implantation
作者: Wang, Y (Wang, Yue); Shen, XL (Shen, Xiao-Liang); Zheng, RL (Zheng, Rui-Lin); Guo, HT (Guo, Hai-Tao); Lv, P (Lv, Peng); Liu, CX (Liu, Chun-Xiao)
来源出版物: OPTICAL ENGINEERING 卷: 57 期: 1 文献号: 017103 DOI: 10.1117/1.OE.57.1.017103 出版年: JAN 2018
摘要: Ion implantation has demonstrated to be an efficient and reliable technique for the fabrication of optical waveguides in a diversity of transparent materials. Photo-thermal-refractive glass (PTR) is considered to be durable and stable holographic recording medium. Optical planar waveguide structures in the PTR glasses were formed, for the first time to our knowledge, by the C3+-ion implantation with single-energy (6.0 MeV) and double-energy (5.5 + 6.0 MeV), respectively. The process of the carbon ion implantation was simulated by the stopping and range of ions in matter code. The morphologies of the waveguides were recorded by a microscope operating in transmission mode. The guided beam distributions of the waveguides were measured by the end-face coupling technique. Comparing with the single-energy implantation, the double-energy implantation improves the light confinement for the dark-mode spectrum. The guiding properties suggest that the carbon-implanted PTR glass waveguides have potential for the manufacture of photonic devices. (c) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)
入藏号: WOS:000424272600067
ISSN: 0091-3286
eISSN: 1560-2303
________________________________________
第 311 条,共 322 条
标题: Research on key technologies of active polarization imaging system
作者: Xie, ML (Xie Meilin); Liu, P (Liu Peng); Ma, CW (Ma Caiwen); Huang, W (Huang Wei); Liang, J (Liang Jian); Feng, XB (Feng Xubin)
来源出版物: OPTIK 卷: 157 页: 556-564 DOI: 10.1016/j.ijleo.2017.11.033 出版年: 2018
摘要: In this paper, one active polarization imaging technique is introduced to enhance the contrast between the target and the sky to overcome the environmental interference such as cloud and fog in the long-range detection of air vehicles. At first, the theory of the whole system, the selection of detection system and the wavelength of laser, and the brief design of the optical system are described. Secondly the selection of the laser power is derived based on the elements such as atmosphere attenuation, and the sensitivity, image contrast and signal-to-noise ratio in the detector. Then the polarization imaging mechanism of the full aperture polarization measurement platform is analyzed. Finally a nonlinear differentiator is proposed to improve the speed stability in the tracking to ensure high imaging quality. The purpose of this paper is to lay a theoretical foundation for active polarization imaging technology and to promote its engineering application in shooting range and other fields. (C) 2017 Elsevier GmbH. All rights reserved.
入藏号: WOS:000424186500070
ISSN: 0030-4026
________________________________________
第 312 条,共 322 条
标题: Modified slanted-edge method to measure the modulation transfer function of camera
作者: Zhang, HS (Zhang, Haosu); Li, C (Li, Chuang); Duan, YX (Duan, Yaxuan)
来源出版物: OPTIK 卷: 157 页: 635-643 DOI: 10.1016/j.ijleo.2017.11.161 出版年: 2018
摘要: The slanted-edge method specified in ISO Standard 12223, which experiences large errors in the camera modulation transfer function(MTF) due to tilt angle error in the knife-edge resulting in non-uniform sampling of the edge spread function. In order to resolve this problem, a modified slanted-edge method for camera MTF measurement is proposed. By applying a simple direct calculation of the Fourier transform of the derivative for the non-uniform sampling data, the camera super-sampled MTF results are obtained. Theoretical simulations for images with and Without noise under different tilt angle errors are run using the proposed method. It is demonstrated that the MTF results are insensitive to tilt angle errors. To verify the accuracy of the proposed method, an experimental setup for camera MTF measurement is established. Measurement results show that the proposed method is superior to traditional methods, and improves the universality of the slanted knife-edge method for camera MTF measurement. (C) 2017 Elsevier GmbH. All rights reserved.
入藏号: WOS:000424186500080
ISSN: 0030-4026
________________________________________
第 313 条,共 322 条
标题: Random selection-based adaptive saliency-weighted RXD anomaly detection for hyperspectral imagery
作者: Liu, WH (Liu, Weihua); Feng, XP (Feng, Xiangpeng); Wang, S (Wang, Shuang); Hu, BL (Hu, Bingliang); Gan, YQ (Gan, Yuquan); Zhang, XR (Zhang, Xiaorong); Lei, T (Lei, Tao)
来源出版物: INTERNATIONAL JOURNAL OF REMOTE SENSING 卷: 39 期: 8 页: 2139-2158 DOI: 10.1080/01431161.2017.1420931 出版年: 2018
摘要: With recent advances in hyperspectral imaging sensors, subtle and concealed targets that cannot be detected by multispectral imagery can be identified. The most widely used anomaly detection method is based on the Reed-Xiaoli (RX) algorithm. This unsupervised technique is preferable to supervised methods because it requires no a priori information for target detection. However, two major problems limit the performance of the RX detector (RXD). First, the background covariance matrix cannot be properly modelled because the complex background contains anomalous pixels and the images contain noise. Second, most RX-like methods use spectral information provided by data samples but ignore the spatial information of local pixels. Based on this observation, this article extends the concept of the weighted RX to develop a new approach called an adaptive saliency-weighted RXD (ASW-RXD) approach that integrates spectral and spatial image information into an RXD to improve anomaly detection performance at the pixel level. We recast the background covariance matrix and the mean vector of the RX function by multiplying them by a joint weight that in fuses spectral and local spatial information into each pixel. To better estimate the purity of the background, pixels are randomly selected from the image to represent background statistics. Experiments on two hyperspectral images showed that the proposed random selection-based ASW RXD (RSASW-RXD) approach can detect anomalies of various sizes, ranging from a few pixels to the sub-pixel level. It also yielded good performance compared with other benchmark methods.
入藏号: WOS:000424236900005
ISSN: 0143-1161
eISSN: 1366-5901
________________________________________
第 314 条,共 322 条
标题: Image sentiment prediction based on textual descriptions with adjective noun pairs
作者: Li, ZH (Li, Zuhe); Fan, YY (Fan, Yangyu); Liu, WH (Liu, Weihua); Wang, FQ (Wang, Fengqin)
来源出版物: MULTIMEDIA TOOLS AND APPLICATIONS 卷: 77 期: 1 页: 1115-1132 DOI: 10.1007/s11042-016-4310-5 出版年: JAN 2018
摘要: We aim to predict the sentiment related information reflected in images based on SentiBank, which is a library including Adjective Noun Pair (ANP) concept detectors for image sentiment analysis. Instead of using only ANP responses in images as mid-level features, we make full use of the ANPs' textual sentiment. We first give each ANP concept in SentiBank a sentiment value by adding together the textual sentiment value of the adjective and that of the noun. Having detected the presence of ANPs in an image, we define an image sentiment value by computing the weighted sum of the textual sentiment values of ANPs describing this image with corresponding ANP responses as weights. On the one hand, we adopt a one-dimension logistic regression model to predict the sentiment orientation according to the image sentiment value. On the other hand, we use the ANP responses detected in an image as mid-level representations to train a regularized logistic regression classifier for sentiment prediction. We finally employ a late fusion algorithm to combine the prediction results from the two schemes. Experimental results reveal that the proposed method which takes into account the textual sentiment of ANPs improves the performance of SentiBank based image sentiment prediction.
入藏号: WOS:000419995400047
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Zuhe                  0000-0002-2511-3226

ISSN: 1380-7501
eISSN: 1573-7721
________________________________________
第 315 条,共 322 条
标题: Waveguiding structures in Yb3+-doped phosphate glasses by double-energy proton and single-energy carbon-ion implantations
作者: Zhu, QF (Zhu, Qi-Feng); Shen, XL (Shen, Xiao-Liang); Zheng, RL (Zheng, Rui-Lin); Lv, P (Lv, Peng); Guo, HT (Guo, Hai-Tao); Li, WN (Li, Wei-Nan); Liu, CX (Liu, Chun-Xiao)
来源出版物: MATERIALS RESEARCH EXPRESS 卷: 5 期: 1 文献号: 016404 DOI: 10.1088/2053-1591/aaa1f7 出版年: JAN 2018
摘要: We report on the construction of wave guiding structures operating at 632.8 nm in the Yb3+-doped phosphate glass by two different techniques: carbon-ion implantation with a single-implant at an energy of 6.0 MeV and a dose of 5.0 x 10(14) ions cm(-2), and proton implantation with a double-implant of energies of (500 vertical bar 550) keV and doses of (1 vertical bar 2) x 10(16) ions cm(-2). The annealing treatments were performed at different temperatures ranging from 260 degrees C to 460 degrees C at internals of 50 degrees C. For the proton-implanted waveguide, the m-line spectrum and the refractive index profile were studied by a modal 2010 prism coupler and a reflectivity calculation method, respectively. The near field patterns in the both cases were recoded by an end-fire coupling system. The carbon-and proton-implanted Yb3+-doped phosphate glass waveguides can propagate guided modes after the continuous annealing, suggesting the applicability in the development of photonics devices.
入藏号: WOS:000419715400002
ISSN: 2053-1591
________________________________________
第 316 条,共 322 条
标题: Application of an interferometric method in phasing the segmented primary mirrors of the high-aperture telescope
作者: Wang, CC (Wang, Chenchen); Fan, XW (Fan, Xuewu); Ma, Z (Ma, Zhen); Zou, GY (Zou, Gangyi); Li, RC (Li, Ruichang)
来源出版物: OPTIK 卷: 154 页: 503-509 DOI: 10.1016/j.ijleo.2017.10.015 出版年: 2018
摘要: The main method to improve the resolution of optical system is enlarging the pupil of the optical system, and by using several or even more small segmented mirrors to get an equivalent large diameter primary mirror is a common way. When the optical system enters the orbit, it should deploy the segmented mirrors first. The image quality of the optical system is determined by the deployed position precision of segmented mirrors. The phase adjusting process can be divided into two processions: coarse phasing and fine phasing. In the coarse phasing, interferometer and electronic speckle pattern interferometry is used to ensure the co-phased position of segmented mirrors on the ground and to obtain stripes on the back of the segmented mirrors respectively. When the optical system is unfolded, obtain the stripe again. Process the former stripe images and the later ones by mean square error, which can obtain the similarity of two images. According to the shape of stripe pattern and the similarity, adjust the position of segmented mirrors to complete the process of large piston adjusting. And analyze the stripe that is obtained by processing the electronic speckle images after the process above. Adjust the position of segmented mirrors according to the results until the adjusting of coarse-phasing is completed. With the simulation results, when the position of segmented mirrors with 0.0001 degrees tilted or 5 nm decentered, the similarity of standard image and simulation results are about 92% and 95% respectively. (C) 2017 Elsevier GmbH. All rights reserved.
入藏号: WOS:000418731200064
ISSN: 0030-4026
________________________________________
第 317 条,共 322 条
标题: Anisotropic narrowing of biphoton wave packet distribution in spontaneous parametric down-conversion with biaxial crystal
作者: Huo, GW (Huo, Guangwen); Zhang, TY (Zhang, Tongyi); Zhang, MZ (Zhang, Meizhi); Zhu, HY (Zhu, Haiyan); Zha, XW (Zha, Xinwei); Chen, H (Chen, Heng)
来源出版物: JOURNAL OF MODERN OPTICS 卷: 65 期: 3 页: 298-305 DOI: 10.1080/09500340.2017.1393568 出版年: 2018
摘要: We investigate theoretically the stronganisotropy in the wave packet distribution of biphoton pairs generated via spontaneous parametric down-conversion (SPDC) process with biaxial crystals. From the angle relationship in biaxial crystals, we deduce the wave function of type I SPDC by considering the longitudinal detuning under paraxial approximation. Taking BiB3O6 (BIBO) as an example, we numerically simulate the single-particle and coincidence distributions in two observation planes under the optimum phase-matching scheme. In contrast to uniaxial crystals, a stronger anisotropy effect and a higher entanglement of the photon pair states are obtained, which are attributed to the complex structure of biaxial crystals. These results are important for the generation of highly entangled biphoton pairs, especially for multi-photon pairs generation.
入藏号: WOS:000418762700008
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Zhang, Meizhi         M-8269-2018         0000-0002-7182-0271

ISSN: 0950-0340
eISSN: 1362-3044
________________________________________
第 318 条,共 322 条
标题: Conductive connection induced speed-up of localized-surface-plasmon dynamics
作者: Cun, P (Cun, Peng); Wang, M (Wang, Meng); Huang, CY (Huang, Cuiying); Huang, P (Huang, Pei); He, XK (He, Xinkui); Wei, ZY (Wei, Zhiyi); Zhang, XP (Zhang, Xinping)
来源出版物: JOURNAL OF OPTICS 卷: 20 期: 1 文献号: 014011 DOI: 10.1088/2040-8986/aa9f47 出版年: JAN 2018
摘要: Conductive connection of localized surface plasmons (LSPs) was achieved by depositing a layer of continuous gold film onto the top surface of a matrix of randomly distributed gold nanoparticles (AuNPs) that were originally isolated on a glass substrate. Ultrafast spectroscopic response of such plasmonic nanostructures was investigated by femtosecond pump-probe detection technique. The transient-absorption data showed large redshift and broadening of the resonance spectrum of the conductively connected AuNPs with respect to the isolated ones. Such effects led to modulation on the evolution dynamics of LSPs in a transient transition spectral band. Making use of the temporal and spectral dislocation between the edges of transition band, we achieved much increased speed of the plasmonic optical switching effect.
入藏号: WOS:000418930300001
ISSN: 2040-8978
eISSN: 2040-8986
________________________________________
第 319 条,共 322 条
标题: Rotating of low-refractive-index microparticles with a quasi-perfect optical vortex
作者: Liang, YS (Liang, Yansheng); Lei, M (Lei, Ming); Yan, SH (Yan, Shaohui); Li, MM (Li, Manman); Cai, YA (Cai, Yanan); Wang, ZJ (Wang, Zhaojun); Yu, XH (Yu, Xianghua); Yao, BL (Yao, Baoli)
来源出版物: APPLIED OPTICS 卷: 57 期: 1 页: 79-84 DOI: 10.1364/AO.57.000079 出版年: JAN 1 2018
摘要: Low-refractive-index microparticles, such as hollow microspheres, have shown great significance in some applications, such as biomedical sensing and targeted drug delivery. However, optical trapping and manipulation of low-refractive-index microparticles are challenging, owing to the repelling force exerted by typical optical traps. In this paper, we demonstrated optical trapping and rotating of large-sized low-refractive-index microparticles by using quasi-perfect optical vortex (quasi-POV) beams, which were generated by Fourier transform of high-order quasi-Bessel beams. Numerical simulation was carried out to characterize the focusing property of the quasi-POV beams. The dynamics of low-refractive-index microparticles in the quasi-POV with various topological charges was investigated in detail. To improve the trapping and rotating performances of the vortex, a point trap was introduced at the center of the ring. Experimental results showed that the quasi-POV was preferable for manipulation of large-sized low-refractive-index microparticles, with its control of the particles' rotating velocity dependent only on the topological charge due to the unchanged orbital radius. (C) 2017 Optical Society of America
入藏号: WOS:000418614400045
PubMed ID: 29328117
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Yu, Xianghua                  0000-0002-7447-1396

ISSN: 1559-128X
eISSN: 2155-3165
________________________________________
第 320 条,共 322 条
标题: High energy Er-doped Q-switched fiber laser with WS2 saturable absorber
作者: Li, L (Li, Lu); Wang, YG (Wang, Yonggang); Wang, ZF (Wang, Zhen Fu); Wang, X (Wang, Xi); Yang, GW (Yang, Guowen)
来源出版物: OPTICS COMMUNICATIONS 卷: 406 特刊: SI 页: 80-84 DOI: 10.1016/j.optcom.2017.01.007 出版年: JAN 1 2018
摘要: The report presents a stable Q-switched Er-doped fiber (EDF) laser with WS2-based saturable absorber (SA). The SA is obtained by mixing WS2 dispersion with polyvinyl alcohol (PVA) into polystyrene cells, and then evaporating them to form WS2/PVA film. The modulation depth (MD) of WS2/PVA is 2% and the saturable intensity (I-sat) is 27.2 MW/cm(2). Employing the WS2/PVA film into EDF laser cavity, stable Q-switched operation is achieved with central wavelength of 1560 nm. The repetition rate can be tuned from 16.15 to 60.88 kHz with increasing pump power from 30 to 320 mW. The single pulse energy increases from 82 to 195 nJ and then decreases down to 156 nJ with increasing pump power from 30 to 320 mW. The pulse width shows the same variation trend. The shortest pulse duration of 2.396 mu s and the maximum single pulse energy of 195 nJ are obtained at the pump power of 220 mW. To the best of our knowledge, 195 nJ is the largest single pulse energy at 1.55 mu m region with TMDs as Q-switcher. The signal-to-noise ratio (SNR) is measured to be 60 dB at the pump power of 130 mW. The long term stability of working is good too. The experimental results evidently show that the WS2/PVA SA can work as a promising Q-switcher for high power fiber lasers. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000415603700013
作者识别号:
作者        Web of Science ResearcherID        ORCID 号
Li, Lu                  0000-0002-3097-1954

ISSN: 0030-4018
eISSN: 1873-0310
________________________________________
第 321 条,共 322 条
标题: Nanotube mode locked, wavelength-tunable, conventional and dissipative solitons fiber laser
作者: Yun, L (Yun, Ling); Zhao, W (Zhao, Wei)
来源出版物: OPTICS COMMUNICATIONS 卷: 406 特刊: SI 页: 205-208 DOI: 10.1016/j.optcom.2017.02.026 出版年: JAN 1 2018
摘要: We report the generation of widely wavelength tunable conventional solitons (CSs) and dissipative solitons (DSs) in an erbium-doped fiber laser passively mode-locked by nanotube saturable absorber. The tuning ranges of CSs and DSs are similar to 15 and similar to 25 nm, respectively. In anomalous dispersion regime, the output CS exhibits symmetrical spectral sidebands with transform-limited pulse duration of similar to 1.1 ps. In the contrastive case of normal dispersion regime, the DS has rectangular spectrum profile and large frequency chirp, which presents pulse duration of similar to 13.5 ps, and can be compressed to similar to 0.4 ps external to the cavity. This fiber laser can provide two distinct types of tunable soliton sources, which is attractive for practical applications in telecommunications. (C) 2017 Published by Elsevier B.V.
入藏号: WOS:000415603700035
ISSN: 0030-4018
eISSN: 1873-0310
________________________________________
第 322 条,共 322 条
标题: Inband pumped passively Q-switched Er: YAG laser at 1645 nm using WS2
作者: Guo, L (Guo, Lei); Li, M (Li, Ming); Li, T (Li, Tao); Zhang, SY (Zhang, Shuaiyi); Yang, KJ (Yang, Kejian); Fan, MQ (Fan, Mingqi); Zhao, SZ (Zhao, Shengzhi)
来源出版物: OPTICS COMMUNICATIONS 卷: 406 特刊: SI 页: 230-233 DOI: 10.1016/j.optcom.2017.01.047 出版年: JAN 1 2018
摘要: A diode-pumped passively Q-switched Er: YAG laser at 1645 nm was demonstrated by using a WS2 saturable absorber (SA). The WS2-SA was prepared by liquid phase exfoliation method and fabricated on a YAG substrate. Under an absorbed pump power of 6.24 W, an average output power of 0.42 W was obtained with a pulse width of 1.8 mu s at a repetition rate of 25 kHz, producing a pulse energy of 16.75 mu J. (C) 2017 Elsevier B.V. All rights reserved.
入藏号: WOS:000415603700038
ISSN: 0030-4018
eISSN: 1873-0310


相关附件
相关文档

实时咨询

问图书馆员:

问学科馆员:

中国科学院西安光学精密机械研究所图书馆
陕公网安备 61019002000960号 陕ICP备05007611