Record 1 of 243

Title: A level set method with shape priors by using locality preserving projections

Author(s): Wang, B (Wang, Bin); Gao, XB (Gao, Xinbo); Li, J (Li, Jie); Li, XL (Li, Xuelong); Tao, DC (Tao, Dacheng)

Source: NEUROCOMPUTING  Volume: 170  Pages: 188-200  DOI: 10.1016/j.neucom.2014.07.086  Published: DEC 25 2015  

Abstract: A novel level set method (LSM) with the constraint of shape priors is proposed to implement a selective image segmentation. Firstly, the shape priors are aligned by using image moment to deprive the spatial related information. Secondly, the aligned shape priors are projected into the subspace expanded by using locality preserving projection to measure the similarity between the shapes. Finally, a new energy functional is built by combing data-driven and shape-driven energy items to implement a selective image segmentation method. We assess the proposed method and some representative LSMs on the synthetic, medical and natural images, the results suggest that the proposed one is superior to the pure data-driven LSMs and the representative LSMs with shape priors. (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000361256000019

Conference Title: International Conference on Intelligent Science and Intelligent Data Engineering (IScIDE)

Conference Date: JUL 31-AUG 02, 2013

Conference Location: Beijing, PEOPLES R CHINA

Author Identifiers:

ISSN: 0925-2312

eISSN: 1872-8286

Record 2 of 243

Title: Generation and three-dimensional characterization of complex nondiffracting optical beams

Author(s): Yu, XH (Yu Xiang-Hua); Yao, BL (Yao Bao-Li); Lei, M (Lei Ming); Yan, SH (Yan Shao-Hui); Yang, YL (Yang Yan-Long); Li, RZ (Li Run-Ze); Cai, YN (Cai Ya-Nan)

Source: ACTA PHYSICA SINICA  Volume: 64  Issue: 24  Article Number: 244203  DOI: 10.7498/aps.64.244203  Published: DEC 20 2015  

Abstract: Nondiffracting optical beams play an important role in contemporary optics due to their special propagation characteristics, i.e., nondiffracting in a diffraction-free zone, shape recovering behind obstacles or self-healing property. Liquid crystal spatial light modulators (LC-SLM) are widely used for generating nondiffracting optical beams in virtue of programmable and dynamic features. In this paper, we propose a complex amplitude modulation technique that can encode any scalar complex fields for generating the complex nondiffracting beams. Before experiment, the phase modulation curve of the phase-only LC-SLM is optimized into being linear in a range of 0-2 pi by gamma correction in the way of variable binary phase gratings. Then, we experimentally generate the nonaccelerating beams, e.g., two zero-order Bessel beams with variable intensity distributions, and the nondiffracting petal-like beams generated by interfering with two coaxial Bessel beams. By scanning a reflection mirror near the focal region along the optical axis, a stack of two-dimensional images is acquired, and then a three-dimensional intensity profile of the beam is reconstructed with a software. We also experimentally demonstrate a new kind of multi-main-lobe accelerating beam with parabolic accelerating trajectory by modifying the spatial spectrum of classical Airy beam. Compared with the so-called vectorial accelerating beam with multiple main lobes in spheroidal coordinates, our generated two-main-lobe accelerating beam has a very high energy efficiency. The self-healing property of the two-main-lobe accelerating beam is also demonstrated. The presented technique can generate a variety of complex nondiffracting optical beams rapidly and obtain their three-dimensional intensity distributions accurately, which has potential applications in the fields of optical microscope, optical date storage, optical trapping, optical micromachining, etc.

Accession Number: WOS:000368828600024

Author Identifiers:

ISSN: 1000-3290

Record 3 of 243

Title: Hydrothermal synthesis of TiO₂ nanostructure films and their photoelectrochemical properties

Author(s): Miao, H (Miao, Hui); Hu, XY (Hu, Xiaoyun); Fan, J (Fan, Jun); Li, CB (Li, Chaoben); Sun, Q (Sun, Qian); Hao, YY (Hao, Yuanyuan); Zhang, GW (Zhang, Guowei); Bai, JT (Bai, Jintao); Hou, X (Hou, Xun)

Source: APPLIED SURFACE SCIENCE  Volume: 358  Pages: 418-424  DOI: 10.1016/j.apsusc.2015.08.212  Part: A  Published: DEC 15 2015  

Abstract: In this study, anatase TiO2 nanostructured films were successfully prepared via Ti foil-assisted hydrothermal synthesis method without any surfactants. With the increase of hydrothermal time from 3 to 12 h, the surface morphologies of the films changed from nanotubes to nanoflowers and the thickness of the films increased from 2.5 to 4.2 mu m. The nanoflowers were seated on a layer of oriented nanotubes and consisted of nanosheets. Both nanotubes and nanosheets were multi-walled, comprising interconnected [TiO6] octahedra. Ti foil and acid-treated Ti foil both formed pieces of thin films on the surface with nanotubes and nanoflowers, respectively. Photoelectrochemistry tests showed that the photocurrent response of the nanotube film was nearly 13.8 mu A/cm(2), which was approximately three times higher than that of nanoflowers film. This indicates that the nanotubes more successfully transferred electrons to the surface of the film as a result of nanotubes providing direct pathways for electrons from the point of injection to the Ti foil electrode. The ultraviolet (UV)-visible-near infrared (NIR) absorption spectra indicated that the nanotube film had a narrower band gap as compared to the nanoflower film. In other words, a relatively low hydrothermal treatment temperature or relatively short hydrothermal treatment time is better for preparing excellent photocurrent response films. (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000366220400052

Conference Title: 1st International Workshop on Graphene and C3N4-based Photocatalysts (IWGCP)

Conference Date: JUN 05-08, 2015

Conference Location: Wuhan Univ Technology, Wuhan, PEOPLES R CHINA

Conference Sponsors: Jianghan Univ, Changsha Univ

Conference Host: Wuhan Univ Technology

Author Identifiers:

ISSN: 0169-4332

eISSN: 1873-5584

Record 4 of 243

Title: Plasmon-induced transparency in terahertz planar metamaterials

Author(s): Chen, X (Chen, Xu); Fan, WH (Fan, Wen-Hui)

Source: OPTICS COMMUNICATIONS  Volume: 356  Pages: 84-89  DOI: 10.1016/j.optcom.2015.07.063  Published: DEC 1 2015  

Abstract: A planar metamaterial structure with plasmon-induced transparency effect in terahertz region is proposed and systematic numerical study is presented in this paper. The metamaterial structure is comprised of two different spilt-ring resonators in the same plane. With the destructive interference coupling between these two split-ring resonators, the proposed metamaterial structure exhibits a large transparency window within a broad absorption spectra. Moreover, the origin of transparency window with extremely low absorption and strong dispersion is clarified by two coupled Lorentzian resonators analytical model, and verified by accurate simulation of the electromagnetic wave propagation in the metamaterial structure. The proposed metamaterial opens up the avenue to design micro-sized functional devices used in switching, modulation, and slowing down terahertz waves. (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000362603600016

Author Identifiers:

ISSN: 0030-4018

eISSN: 1873-0310

Record 5 of 243

Title: Mining Spatial-Temporal Patterns and Structural Sparsity for Human Motion Data Denoising

Author(s): Feng, YF (Feng, Yinfu); Ji, MM (Ji, Mingming); Xiao, J (Xiao, Jun); Yang, XS (Yang, Xiaosong); Zhang, JJ (Zhang, Jian J.); Zhuang, YT (Zhuang, Yueting); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 45  Issue: 12  Pages: 2693-2706  DOI: 10.1109/TCYB.2014.2381659  Published: DEC 2015  

Abstract: Motion capture is an important technique with a wide range of applications in areas such as computer vision, computer animation, film production, and medical rehabilitation. Even with the professional motion capture systems, the acquired raw data mostly contain inevitable noises and outliers. To denoise the data, numerous methods have been developed, while this problem still remains a challenge due to the high complexity of human motion and the diversity of real-life situations. In this paper, we propose a data-driven-based robust human motion denoising approach by mining the spatial-temporal patterns and the structural sparsity embedded in motion data. We first replace the regularly used entire pose model with a much fine-grained partlet model as feature representation to exploit the abundant local body part posture and movement similarities. Then, a robust dictionary learning algorithm is proposed to learn multiple compact and representative motion dictionaries from the training data in parallel. Finally, we reformulate the human motion denoising problem as a robust structured sparse coding problem in which both the noise distribution information and the temporal smoothness property of human motion have been jointly taken into account. Compared with several state-of-the-art motion denoising methods on both the synthetic and real noisy motion data, our method consistently yields better performance than its counterparts. The outputs of our approach are much more stable than that of the others. In addition, it is much easier to setup the training dataset of our method than that of the other data-driven-based methods.

Accession Number: WOS:000365320300006

PubMed ID: 25561602

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 6 of 243

Title: Efficient Video Stitching Based on Fast Structure Deformation

Author(s): Li, J (Li, Jing); Xu, W (Xu, Wei); Zhang, JG (Zhang, Jianguo); Zhang, MJ (Zhang, Maojun); Wang, ZM (Wang, Zhengming); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 45  Issue: 12  Pages: 2707-2719  DOI: 10.1109/TCYB.2014.2381774  Published: DEC 2015  

Abstract: In computer vision, video stitching is a very challenging problem. In this paper, we proposed an efficient and effective wide-view video stitching method based on fast structure deformation that is capable of simultaneously achieving quality stitching and computational efficiency. For a group of synchronized frames, firstly, an effective double-seam selection scheme is designed to search two distinct but structurally corresponding seams in the two original images. The seam location of the previous frame is further considered to preserve the inter-frame consistency. Secondly, along the double seams, 1-D feature detection and matching is performed to capture the structural relationship between the two adjacent views. Thirdly, after feature matching, we propose an efficient algorithm to linearly propagate the deformation vectors to eliminate structure misalignment. At last, image intensity misalignment is corrected by rapid gradient fusion based on the successive over relaxation iteration (SORI) solver. A principled solution to the initialization of the SORI significantly reduced the number of iterations required. We have compared favorably our method with seven state-of-the-art image and video stitching algorithms as well as traditional ones. Experimental results show that our method outperforms the existing ones compared in terms of overall stitching quality and computational efficiency.

Accession Number: WOS:000365320300007

PubMed ID: 25561603

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 7 of 243

Title: Yb-doped passively mode-locked fiber laser with Bi₂Te₃-deposited

Author(s): Li, L (Li Lu); Yan, PG (Yan Pei-Guang); Wang, YG (Wang Yong-Gang); Duan, LN (Duan Li-Na); Sun, H (Sun Hang); Si, JH (Si Jin-Hai)

Source: CHINESE PHYSICS B  Volume: 24  Issue: 12  Article Number: 124204  DOI: 10.1088/1674-1056/24/12/124204  Published: DEC 2015  

Abstract: In this study we present an all-normal-dispersion Yb-doped fiber laser passively mode-locked with topological insulator (Bi2Te3) saturable absorber. The saturable absorber device is fabricated by depositing Bi2Te3 on a tapered fiber through using pulsed laser deposition (PLD) technology, which can give rise to less non-saturable losses than most of the solution processing methods. Owing to the long interaction length, Bi2Te3 is not exposed to high optical power, which allows the saturable absorber device to work in a high power regime. The modulation depth of this kind of saturable absorber is measured to be 10%. By combining the saturable absorber device with Yb-doped fiber laser, a mode-locked pulse operating at a repetition rate of 19.8 MHz is achieved. The 3-dB spectral width and pulse duration are measured to be 1.245 nm and 317 ps, respectively.

Accession Number: WOS:000366977800026

Author Identifiers:

ISSN: 1674-1056

eISSN: 1741-4199

Record 8 of 243

Title: Fraunhofer diffraction of Laguerre-Gaussian beam caused by a dynamic superposed dual-triangular aperture

Author(s): Li, XZ (Li, Xinzhong); Tai, YP (Tai, Yuping); Nie, ZG (Nie, Zhaogang); Wang, H (Wang, Hui); Li, HH (Li, Hehe); Wang, JG (Wang, Jingge); Tang, J (Tang, Jie); Wang, YS (Wang, Yishan)

Source: OPTICAL ENGINEERING  Volume: 54  Issue: 12  Article Number: 123113  DOI: 10.1117/1.OE.54.12.123113  Published: DEC 2015  

Abstract: We investigate the Fraunhofer diffraction of a Laguerre-Gaussian (LG) beam incident on a dynamic superposed dual-triangular aperture. The evolution of the diffraction pattern from this aperture is analyzed experimentally and theoretically. A special aperture, called the hex-star triangular aperture, demonstrates interesting diffraction patterns. Further, the diffraction properties of integer, half-integer, and fractional orders of topological charges at the Fraunhofer zone are studied by using the hex-star triangular aperture. This study can provide additional information to enhance the understanding of the diffraction properties of the LG beam transmitted through a complex aperture. (C) 2015 Society of Photo-Optical Instrumentation Engineers (SPIE)

Accession Number: WOS:000368418300016

Author Identifiers:

ISSN: 0091-3286

eISSN: 1560-2303

Record 9 of 243

Title: Passively Q-switched Nd:YAG laser with a MoS₂ solution saturable absorber

Author(s): Lin, T (Lin, Tao); Sun, H (Sun, Hang); Wang, X (Wang, Xi); Mao, D (Mao, Dong); Wang, YG (Wang, Yonggang); Li, L (Li, Lu); Duan, LN (Duan, Lina)

Source: LASER PHYSICS  Volume: 25  Issue: 12  Article Number: 125805  DOI: 10.1088/1054-660X/25/12/125805  Published: DEC 2015  

Abstract: This study presents a passively Q-switched Nd:YAG laser using a MoS2 solution as a saturable absorber. The prepared MoS2 solution saturable absorber features adjustable optical absorption, high heat dissipation, and non-contact damage. By inserting the MoS2 solution saturable absorber into a Z-type Nd:YAG laser cavity, a stable Q-switched laser with the maximum repetition rate of 20.8 KHz centered at 1064.24 nm was achieved, with the shortest pulse width at 2.8 mu s. The results experimentally confirm the potential application of a MoS2 solution saturable absorber for high performance Q-switched solid-state lasers.

Accession Number: WOS:000365351200020

Author Identifiers:

ISSN: 1054-660X

eISSN: 1555-6611

Record 10 of 243

Title: Highly efficient nonlinear ellipse rotation in bulk SrTiO₃ crystal and its applications

Author(s): Sun, QB (Sun, Qibing); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu); Li, SP (Li, Shaopeng); Han, J (Han, Jing)

Source: LASER PHYSICS  Volume: 25  Issue: 12  Article Number: 125403  DOI: 10.1088/1054-660X/25/12/125403  Published: DEC 2015  

Abstract: We investigated the highly efficient, nonlinear ellipse rotation (NER) effect in bulk SrTiO3 crystal, which provides practical application as a pulse cleaner for ultrashort pulses. A highly stable, ultrafast NER effect was realized by using a bulk SrTiO3 crystal with a fast response time, strong optical Kerr effect, high damage threshold, and wide transmission wavelength range. Transmissivity higher than 30% was obtained at a level of several mJ, in which the temporal contrast can be enhanced by about three orders of magnitude. This provides a simple and feasible technology for improving the temporal contrast for the ultrahigh power laser system.

Accession Number: WOS:000365351200012

Author Identifiers:

ISSN: 1054-660X

eISSN: 1555-6611

Record 11 of 243

Title: Linkage of Dual Frequency Combs Based on All Polarization-Maintaining Femtosecond Fiber Lasers

Author(s): Xu, X (Xu, Xin); Feng, Y (Feng, Ye); Liu, YS (Liu, Yuanshan); Hu, XH (Hu, Xiaohong); Li, FT (Li, Feitao); Zhang, T (Zhang, Ting); Zhang, W (Zhang, Wei); Yang, Z (Yang, Zhi); Cheng, Z (Cheng, Zhao); Zhao, W (Zhao, Wei); Wang, YS (Wang, Yishan)

Source: IEEE PHOTONICS TECHNOLOGY LETTERS  Volume: 27  Issue: 23  Pages: 2421-2424  DOI: 10.1109/LPT.2015.2462080  Published: DEC 1 2015  

Abstract: Perfect linkage of dual frequency combs based on all polarization-maintaining femtosecond fiber lasers is demonstrated. By employing two independent tracking feedback controlling circuits, the repetition frequency (f(r)) and the carrier-envelope offset frequency (f(ceo)) of the slave frequency comb track the master's f(r) and f(ceo), respectively. The correlation coefficients of the dual f(r)'s and the dual f(ceo)'s are up to 0.99 and 0.98, which indicate an ideal linkage between the dual frequency combs. To the best of our knowledge, this is the first report about linkage of dual frequency combs.

Accession Number: WOS:000363209500001

Author Identifiers:

ISSN: 1041-1135

eISSN: 1941-0174

Record 12 of 243

Title: Degradation of high power single emitter laser modules using nanosilver paste in continuous pulse conditions

Author(s): Yan, HD (Yan, Haidong); Mei, YH (Mei, Yunhui); Li, X (Li, Xin); Zhang, P (Zhang, Pu); Lu, GQ (Lu, Guo-Quan)

Source: MICROELECTRONICS RELIABILITY  Volume: 55  Issue: 12  Special Issue: SI  Pages: 2532-2541  DOI: 10.1016/j.microrel.2015.07.037  Part: A  Published: DEC 2015  

Abstract: This paper is mainly reported to a pulse reliability investigation of high power single emitter laser modules with nanosilver paste. Comparative experiments in continuous pulse conditions for the laser modules packaged with nanosilver paste, indium and AuSn solders were conducted. The results indicate that the laser modules attached by nanosilver paste have a longer-term lifetime than those with indium and AuSn solders in continuous pulse conditions. Transient thermal behavior and coupled thermo-mechanical behavior in continuous pulse conditions are simulated by finite element method (FEM). A semi-empirical model based on Arrhenius relationship is established to provide relative reliability assessments for laser modules by combining with the simulating results. (C) 2015 Elsevier Ltd. All rights reserved.

Accession Number: WOS:000367773000010

Author Identifiers:

ISSN: 0026-2714

Record 13 of 243

Title: A Class of Manifold Regularized Multiplicative Update Algorithms for Image Clustering

Author(s): Yang, SM (Yang, Shangming); Yi, Z (Yi, Zhang); He, XF (He, Xiaofei); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON IMAGE PROCESSING  Volume: 24  Issue: 12  Pages: 5302-5314  DOI: 10.1109/TIP.2015.2457033  Published: DEC 2015  

Abstract: Multiplicative update algorithms are important tools for information retrieval, image processing, and pattern recognition. However, when the graph regularization is added to the cost function, different classes of sample data may be mapped to the same subspace, which leads to the increase of data clustering error rate. In this paper, an improved nonnegative matrix factorization (NMF) cost function is introduced. Based on the cost function, a class of novel graph regularized NMF algorithms is developed, which results in a class of extended multiplicative update algorithms with manifold structure regularization. Analysis shows that in the learning, the proposed algorithms can efficiently minimize the rank of the data representation matrix. Theoretical results presented in this paper are confirmed by simulations. For different initializations and data sets, variation curves of cost functions and decomposition data are presented to show the convergence features of the proposed update rules. Basis images, reconstructed images, and clustering results are utilized to present the efficiency of the new algorithms. Last, the clustering accuracies of different algorithms are also investigated, which shows that the proposed algorithms can achieve state-of-the-art performance in applications of image clustering.

Accession Number: WOS:000362488900015

PubMed ID: 26186793

Author Identifiers:

ISSN: 1057-7149

eISSN: 1941-0042

Record 14 of 243

Title: Attitude Disturbance Correction for Binocular Vision Cameras in Rendezvous and Docking

Author(s): Zhai, Y (Zhai, You); Zeng, L (Zeng, Luan); Xiong, W (Xiong, Wei); Shan, QS (Shan, Qiusha)

Source: IEEE AEROSPACE AND ELECTRONIC SYSTEMS MAGAZINE  Volume: 30  Issue: 12  Pages: 34-40  DOI: 10.1109/MAES.2015.150019  Published: DEC 2015  

Accession Number: WOS:000368406300004

Author Identifiers:

ISSN: 0885-8985

eISSN: 1557-959X

Record 15 of 243

Title: Tracking Human Pose Using Max-Margin Markov Models

Author(s): Zhao, L (Zhao, Lin); Gao, XB (Gao, Xinbo); Tao, DC (Tao, Dacheng); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON IMAGE PROCESSING  Volume: 24  Issue: 12  Pages: 5274-5287  DOI: 10.1109/TIP.2015.2473662  Published: DEC 2015  

Abstract: We present a new method for tracking human pose by employing max-margin Markov models. Representing a human body by part-based models, such as pictorial structure, the problem of pose tracking can be modeled by a discrete Markov random field. Considering max-margin Markov networks provide an efficient way to deal with both structured data and strong generalization guarantees, it is thus natural to learn the model parameters using the max-margin technique. Since tracking human pose needs to couple limbs in adjacent frames, the model will introduce loops and will be intractable for learning and inference. Previous work has resorted to pose estimation methods, which discard temporal information by parsing frames individually. Alternatively, approximate inference strategies have been used, which can overfit to statistics of a particular data set. Thus, the performance and generalization of these methods are limited. In this paper, we approximate the full model by introducing an ensemble of two tree-structured sub-models, Markov networks for spatial parsing and Markov chains for temporal parsing. Both models can be trained jointly using the max-margin technique, and an iterative parsing process is proposed to achieve the ensemble inference. We apply our model on three challengeable data sets, which contains highly varied and articulated poses. Comprehensive experimental results demonstrate the superior performance of our method over the state-of-the-art approaches.

Accession Number: WOS:000362488900013

PubMed ID: 26336122

Author Identifiers:

ISSN: 1057-7149

eISSN: 1941-0042

Record 16 of 243

Title: Learning a Tracking and Estimation Integrated Graphical Model for Human Pose Tracking

Author(s): Zhao, L (Zhao, Lin); Gao, XB (Gao, Xinbo); Tao, DC (Tao, Dacheng); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS  Volume: 26  Issue: 12  Pages: 3176-3186  DOI: 10.1109/TNNLS.2015.2411287  Published: DEC 2015  

Abstract: We investigate the tracking of 2-D human poses in a video stream to determine the spatial configuration of body parts in each frame, but this is not a trivial task because people may wear different kinds of clothing and may move very quickly and unpredictably. The technology of pose estimation is typically applied, but it ignores the temporal context and cannot provide smooth, reliable tracking results. Therefore, we develop a tracking and estimation integrated model (TEIM) to fully exploit temporal information by integrating pose estimation with visual tracking. However, joint parsing of multiple articulated parts over time is difficult, because a full model with edges capturing all pairwise relationships within and between frames is loopy and intractable. In previous models, approximate inference was usually resorted to, but it cannot promise good results and the computational cost is large. We overcome these problems by exploring the idea of divide and conquer, which decomposes the full model into two much simpler tractable submodels. In addition, a novel two-step iteration strategy is proposed to efficiently conquer the joint parsing problem. Algorithmically, we design TEIM very carefully so that: 1) it enables pose estimation and visual tracking to compensate for each other to achieve desirable tracking results; 2) it is able to deal with the problem of tracking loss; and 3) it only needs past information and is capable of tracking online. Experiments are conducted on two public data sets in the wild with ground truth layout annotations, and the experimental results indicate the effectiveness of the proposed TEIM framework.

Accession Number: WOS:000365312800017

PubMed ID: 25826809

Author Identifiers:

ISSN: 2162-237X

eISSN: 2162-2388

Record 17 of 243

Title: Sparse kernel entropy component analysis for dimensionality reduction of biomedical data

Author(s): Shi, J (Shi, Jun); Jiang, QK (Jiang, Qikun); Zhang, Q (Zhang, Qi); Huang, QH (Huang, Qinghua); Li, XL (Li, Xuelong)

Source: NEUROCOMPUTING  Volume: 168  Pages: 930-940  DOI: 10.1016/j.neucom.2015.05.032  Published: NOV 30 2015  

Abstract: Dimensionality reduction is ubiquitous in biomedical applications. A newly proposed spectral dimensionality reduction method, named kernel entropy component analysis (KECA), can reveal the structure related to Renyi entropy of an input space data set. However, each principal component in the Hilbert space depends on all training samples in KECA, causing degraded performance. To overcome this drawback, a sparse KECA (SKECA) algorithm based on a recursive divide-and-conquer (DC) method is proposed in this work. The original large and complex problem of KECA is decomposed into a series of small and simple sub-problems, and then they are solved recursively. The performance of SKECA is evaluated on four biomedical datasets, and compared with KECA, principal component analysis (PCA), kernel PCA (KPCA), sparse PCA and sparse KPCA. Experimental results indicate that the SKECA outperforms conventional dimensionality reduction algorithms, even for high order dimensional features. It suggests that SKECA is potentially applicable to biomedical data processing. (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000359165000091

Author Identifiers:

ISSN: 0925-2312

eISSN: 1872-8286

Record 18 of 243

Title: Video-based road detection via online structural learning

Author(s): Yuan, Y (Yuan, Yuan); Jiang, ZY (Jiang, Zhiyu); Wang, Q (Wang, Qi)

Source: NEUROCOMPUTING  Volume: 168  Pages: 336-347  DOI: 10.1016/j.neucom.2015.05.092  Published: NOV 30 2015  

Abstract: Video-based road detection is a crucial enabler for the successful development of driver assistant and robot navigation systems. But reliable detection is still on its infancy and deserves further research. In order to adapt to the situation consisting of environmental varieties, an online framework is proposed focusing on exploring the structure cue of the feature vectors. Through the structural support vector machine, the road boundary and non-boundary instances are firstly discriminated. Then they are utilized to fit a complete road boundary. After that, the road region is accordingly inferred and the obtained results are treated as ground truth to update the learned model. Three contributions are claimed in this work: online-learning updating, structural information consideration, and targeted sampling selection. The proposed method is finally evaluated on several challenging videos captured by ourselves. Qualitative and quantitative results show that it outperforms the other competitors. (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000359165000034

Author Identifiers:

ISSN: 0925-2312

eISSN: 1872-8286

Record 19 of 243

Title: Improved multiple-wavelength Brillouin-Raman fiber laser assisted by four-wave mixing with a micro-air cavity

Author(s): Li, XJ (Li, Xuejiao); Ren, LY (Ren, Liyong); Lin, X (Lin, Xiao); Ju, HJ (Ju, Haijuan); Chen, N (Chen, Nana); Liang, J (Liang, Jian); Ren, KL (Ren, Kaili); Xu, YP (Xu, Yiping)

Source: APPLIED OPTICS  Volume: 54  Issue: 33  Pages: 9919-9924  DOI: 10.1364/AO.54.009919  Published: NOV 20 2015  

Abstract: In this paper, a multiple-wavelength Brillouin-Raman fiber laser (MBRFL) with enhanced performance is presented. This is attributed to the improved Fresnel reflection, thus strengthening four-wave mixing in the fiber laser cavity due to the insertion of a micro-air cavity. As a result, compared with the conventional MBRFL without a micro-air cavity, the thresholds of Brillouin Stokes (BS) lines are observed to be reduced, and more BS lines can be generated. In the experiment, a MBRFL having 40 BS lines is achieved with good stability on laser wavelengths and output power. In view of the fact that more BS lines can be established with a simple scheme and low pump power, our MBRFL promises to be employed as a multiwavelength source for optical communication. (C) 2015 Optical Society of America

Accession Number: WOS:000364988100040

PubMed ID: 26836558

ISSN: 1559-128X

eISSN: 2155-3165

Record 20 of 243

Title: Combined analysis of tunable phase mask within spatial and frequency domain

Author(s): Zhou, L (Zhou Liang); Liu, ZH (Liu Zhao-Hui); She, WJ (She Wen-Ji)

Source: ACTA PHYSICA SINICA  Volume: 64  Issue: 22  Article Number: 224207  DOI: 10.7498/aps.64.224207  Published: NOV 20 2015  

Abstract: Wavefront coding technique is a powerful technique which overcomes the defects of traditional way to extend depth of field. By inserting a phase mask into the traditional incoherent imaging system, wavefront coding technique does not reduce the resolution and the light gathering power of the optical system but enlarges the depth of field of incoherent imaging system. Although several kinds of phase masks have been reported, cubic phase mask is still of a classical type which has been investigated widely both in spatial and frequency domain. Since the phase profiles of phase masks adopted in classical wavefront coding systems are predefined with specific optical systems, the extension of depth of field is not tunable. Tunable wavefront coding systems are introduced by using a pair of detachable phase masks, which is possible to control the depth of field and bandwidth of system by changing the position of each component with respect to the pupil center. Ojeda-Castaneda [Ojeda-Castaneda J, Rodriguez M, Naranjo R 2010 Proceedings of Progress in Electronics Research Symposium, Cambridge, July 5-8, 2010 p531] proposed to use a pair of cosine phase masks to make defocus sensitivity tunable. Zhao [Zhao H, Wei J X 2014 Opt. Commun. 326 35] investigated an improved version of Ojeda-Castaneda's design in frequency domain and found that the proposed system realized tunable bandwidth. The present study, based on the work of Zhao, analyzes the tunable characteristics of a pair of simple modified detachable cubic phase masks in spatial domain and frequency domain. Firstly, the ray aberration theory is adopted to give mathematical analyses and ray aberration maps of the proposed tunable phase mask. Based on the mathematical derivations, the size of point spread function (PSF) of system can be changed not only by profile of each cubic mask but also by the each mask displacement relative to pupil center. Secondly, a mathematical PSF based on the stationary phase method is derived in spatial domain. Simulations indicate that the positions of PSF translate in the image plane with the displacements of phase mask profile and the position of each component with respect to the pupil center. By analyzing the oscillations of PSF, the effective bandwidth is obtained. Through the expression, we can conclude that the effective bandwidth can be changed by the position, mask profile of each component and defocus. Only when the addition of two mask profiles is large enough, can the effective bandwidth be simplified without adding the influence of defocus. In addition, though the approximate expression of magnitude transfer of function (MTF) has been given by adopting stationary phase method in the appendix of previous work, it cannot give an intuitive grasp of the effective bandwidth in MTF map. Unlike the MTF expression derived before, the exact optical transfer function (OTF) expression is derived by adopting Fresnel integral in frequency domain. Exact MTF and phase transfer function (PTF) can be derived from OTF. Based on the exact MTF expression, simulations give an intuitive effective bandwidth in MTF map. Simulations also show the nonlinear property of PTF. The effective bandwidth and MTF can be changed by different phase mask profiles and positions, which indicate that the effective bandwidth and defocus sensitivity can be tuned. Analyses are conducted both in spatial domain and in frequency domain to verify the tunable property of the proposed phase mask, which provides theoretical foundation for tunable wavefront coding system design.

Accession Number: WOS:000368824600016

Author Identifiers:

ISSN: 1000-3290

Record 21 of 243

Title: Metal-dielectric-metal based narrow band absorber for sensing applications

Author(s): Lu, XY (Lu, Xiaoyuan); Wan, RG (Wan, Rengang); Zhang, TY (Zhang, Tongyi)

Source: OPTICS EXPRESS  Volume: 23  Issue: 23  Pages: 29842-29847  DOI: 10.1364/OE.23.029842  Published: NOV 16 2015  

Abstract: We have investigated numerically the narrowband absorption property of a metal-dielectric-metal based structure which includes a top metallic nanoring arrays, a metal backed plate, and a middle dielectric spacer. Its absorption is up to 90% with linewidth narrower than 10 nm. This can be explained in terms of surface lattice resonance of the periodic structure. The spectrum with the sharp absorption dip, i.e. the lattice resonance, strongly depends on the refractive index of media surrounding the nanorings. This feature can be explored to devise a refractive index sensor, of which the bulk sensitivity factor is one order larger than that based on gap resonance mode, while the surface sensitivity factor can be two times larger. The proposed narrowband absorber has potential in applications of plasmonic biosensors. (C) 2015 Optical Society of America

Accession Number: WOS:000366611500053

PubMed ID: 26698467

ISSN: 1094-4087

Record 22 of 243

Title: Design of short wave infrared imaging spectrometer system based on CDP

Author(s): Zhang, ZF (Zhang, Zhoufeng); Hu, BL (Hu, Bingliang); Yin, QY (Yin, Qinye); Yu, T (Yu, Tao); Li, SY (Li, Siyuan); Gao, XH (Gao, Xiaohui); Zhang, HJ (Zhang, Hongjian)

Source: OPTICS EXPRESS  Volume: 23  Issue: 23  Pages: 29758-29763  DOI: 10.1364/OE.23.029758  Published: NOV 16 2015  

Abstract: A compact static infrared snapshot imaging spectrometer (ISIS) is designed in order to satisfy the application requirements of real-time spectral imaging for the moving targets. It consists of a CDP (crossed dispersion prism), an imaging lens, and a detector. Here we describe the spectral imaging principle, and design a short wave infrared imaging spectrometer with 4.8 degrees field of view, the measured spectrum is from 0.9 mu m to 2.5 mu m and is sampled by 40 spectral channels. This instrument has a large potential for detecting, locating and identifying unknown energetic events in real-time. (C) 2014 Optical Society of America

Accession Number: WOS:000366611500044

PubMed ID: 26698458

Author Identifiers:

ISSN: 1094-4087

Record 23 of 243

Title: Extracting nanosecond pulse signals via stochastic resonance generated by surface plasmon bistability

Author(s): Han, J (Han, Jing); Liu, HJ (Liu, Hongjun); Sun, QB (Sun, Qibing); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu); Li, SP (Li, Shaopeng)

Source: OPTICS LETTERS  Volume: 40  Issue: 22  Pages: 5367-5370  DOI: 10.1364/OL.40.005367  Published: NOV 15 2015  

Abstract: A technology is investigated to extract nanosecond pulse noise hidden signals via stochastic resonance, which is based on surface plasmon bistability. A theoretical model for recovering nanosecond pulse signals is derived to describe the nonlinear process. It is found that the incident angle, polarization state, medium properties, and input noise intensity all determine the efficiency and fidelity of the output signal. The bistable behavior of the output intensity can be accurately controlled to obtain a cross-correlation gain larger than 6 in a wide range of input signal-to-noise ratio from 1:5 to 1:30. Meanwhile, the distortion in the time domain induced by phase shift can be reduced to a negligible level. This work provides a potential method for detecting low-level or hidden pulse signals in various communication fields. (C) 2015 Optical Society of America

Accession Number: WOS:000366133400060

PubMed ID: 26565876

Author Identifiers:

ISSN: 0146-9592

eISSN: 1539-4794

Record 24 of 243

Title: Subwavelength beam focusing via multiple-metal slits arranged along a triangle surface

Author(s): Jia, S (Jia, Sen); Wu, YM (Wu, Yiming); Si, JH (Si, Jinhai); Chen, F (Chen, Feng); Hou, X (Hou, Xun)

Source: OPTICS COMMUNICATIONS  Volume: 355  Pages: 586-590  DOI: 10.1016/j.optcom.2015.06.024  Published: NOV 15 2015  

Abstract: A compact plasmonic structure is proposed to actualize the subwavelength beam focusing, through a metal slit array arranged along a triangular or trapezium surface profile. The incident light passes through the metal slits in the form of surface plasmon polaritons (SPPs) and then scattered into radiation fields. The constructive interference of radiation fields from individual slits with different depths and widths gives rise to beam focusing. The advantages of the proposed plasmonic lens are having a much smaller lateral dimension and broad working wavelength range. This is of importance for realizing densely integrated photonic circuits. The finite-difference time-domain (FDTD) method is employed to verify the proposed design. The simulation results indicate that the focal spot is beyond the diffraction limit. (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000362861400089

Author Identifiers:

ISSN: 0030-4018

eISSN: 1873-0310

Record 25 of 243

Title: Coherence in ultrafast laser-induced periodic surface structures

Author(s): Zhang, H (Zhang, Hao); Colombier, JP (Colombier, Jean-Philippe); Li, C (Li, Chen); Faure, N (Faure, Nicolas); Cheng, GH (Cheng, Guanghua); Stoian, R (Stoian, Razvan)

Source: PHYSICAL REVIEW B  Volume: 92  Issue: 17  Article Number: 174109  DOI: 10.1103/PhysRevB.92.174109  Published: NOV 13 2015  

Abstract: Ultrafast laser irradiation can trigger anisotropically structured nanoscaled gratinglike arrangements of matter, the laser-induced periodic surface structures (LIPSSs). We demonstrate here that the formation of LIPSS is intrinsically related to the coherence of the laser field. Employing several test materials that allow large optical excursions, we observe the effect of randomizing spatial phase in generating finite domains of ripples. Using three-dimensional finite-difference time-domain methods, we evaluate energy deposition patterns below a material's rough surface and show that modulated pattern, i.e., a spatially ordered electromagnetic solution, results from the coherent superposition of waves. By separating the field scattered from a surface rough topography from the total field, the inhomogeneous energy absorption problem is reduced to a simple interference equation. We further distinguish the contribution of the scattered near field and scattered far field on various types of inhomogeneous energy absorption features. It is found that the inhomogeneous energy absorption which could trigger the low-spatial-frequency LIPSSs (LSFLs) and high-spatial-frequency LIPSSs (HSFLs) of periodicity Lambda > lambda/Re((n) over tilde) are due to coherent superposition between the scattered far field (propagation) and the refracted field, while HSFLs of Lambda > lambda/Re((n) over tilde) are triggered by coherent superposition between the scattered near field (evanescent) and the refracted field. This is a general scenario that involves a topography-induced scattering phenomenon and stationary evanescent fields, being applied to two model case materials that exhibit large optical excursions upon excitation (W, Si) and nonplasmonic to plasmonic transitions. We indicate the occurrence of a general light interference phenomenon that does not necessarily involve wavelike surface plasmonic excitation. Finally, we discuss the role of interference field and scattered field on the enhancement of LIPSSs by simulating interpulse feedback effects and provide the electromagnetic origin of grooves (Lambda > lambda) related to a feedback-driven topography evolution. Those results strongly suggest the electromagnetic interpretation of LIPSSs in interplay with an evolving surface topography.

Accession Number: WOS:000368094200001

Author Identifiers:

ISSN: 2469-9950

eISSN: 2469-9969

Record 26 of 243

Title: Effect of nano-sized cerium zirconium oxide solid solution on far-infrared emission properties of tourmaline powders

Author(s): Guo, B (Guo, Bin); Yang, LQ (Yang, Liqing); Hu, WJ (Hu, Weijie); Li, WL (Li, Wenlong); Wang, HJ (Wang, Haojing)

Source: MODERN PHYSICS LETTERS B  Volume: 29  Issue: 30  Article Number: 1550183  DOI: 10.1142/S0217984915501833  Published: NOV 10 2015  

Abstract: Far-infrared functional nanocomposites were prepared by the co-precipitation method using natural tourmaline (XY(3)Z(6)Si(6)O(18)(BO3)(3)V3W, where X is Na+, Ca2+, K+, or vacancy; Y is Mg2+, Fe2+, Mn2+, Al3+, Fe3+, Mn3+, Cr3+, Li+, or Ti4+; Z is Al3+, Mg2+, Cr3+, or V3+; V is O2-, OH-; and W is O2-, OH-, or F-) powders, ammonium cerium(IV) nitrate and zirconium(IV) nitrate pentahydrate as raw materials. The reference sample, tourmaline modified with ammonium cerium(IV) nitrate alone was also prepared by a similar precipitation route. The results of Fourier transform infrared spectroscopy show that tourmaline modified with Ce and Zr has a better far-infrared emission property than tourmaline modified with Ce alone. Through characterization by transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), the mechanism for oxygen evolution during the heat process in the two composite materials was systematically studied. The XPS spectra show that Fe3+ ratio inside tourmaline modified with Ce alone can be raised by doping Zr. Moreover, it is showed that there is a higher Ce3+ ratio inside the tourmaline modified with Ce and Zr than tourmaline modified with Ce alone. In addition, XRD results indicate the formation of CeO2 and Ce1-xZrxO2 crystallites during the heat treatment and further TEM observations show they exist as nanoparticles on the surface of tourmaline powders. Based on these results, we attribute the improved far-infrared emission properties of Ce-Zr doped tourmaline to the enhanced unit cell shrinkage of the tourmaline arisen from much more oxidation of Fe2+ to Fe3+ inside the tourmaline caused by the change in the catalyst redox properties of CeO2 brought about by doping with Zr4+. In all samples, tourmaline modified with 7.14 wt.% Ce and 1.86 wt.% Zr calcined at 800 degrees C for 5 h has the best far-infrared emission property with the maximum emissivity value of 98%.

Accession Number: WOS:000364504900002

ISSN: 0217-9849

eISSN: 1793-6640

Record 27 of 243

Title: Prediction of nested complementary pattern in argon dielectric-barrier discharge at atmospheric pressure

Author(s): Jiang, WM (Jiang, Weiman); Li, J (Li, Jing); Tang, J (Tang, Jie); Wang, YS (Wang, Yishan); Zhao, W (Zhao, Wei); Duan, YX (Duan, Yixiang)

Source: SCIENTIFIC REPORTS  Volume: 5  Article Number: 16391  DOI: 10.1038/srep16391  Published: NOV 10 2015  

Abstract: A two-dimensional self-consistent fluid model was employed to investigate the spatiotemporal nonlinear behavior in an argon glow-like/Townsend-like dielectric-barrier discharge (DBD) at atmospheric pressure. The discharge is characterized by a major current pulse with a residual one ahead per half cycle of the external voltage. The two current pulses are operated in glow mode, but with Townsend mode between them. Contrasting spatial discharge structures are complementarily presented not only at two current pulses in the same half cycle but also during the discharge in the two adjacent-half cycles, resulting in the formation of a unique nested complementary pattern each cycle. This peculiar behavior mainly lies in the fact that sufficient charged particles are trapped in the gas gap due to the last discharge and able to dominate the subsequent discharge through the "spatial memory effect". The charge transport regime reveals that this nested complementary pattern is presented only in a limited range of driving frequency.

Accession Number: WOS:000364380400001

PubMed ID: 26552714

Author Identifiers:

ISSN: 2045-2322

Record 28 of 243

Title: Nonlinear restoration of pulse and high noisy images via stochastic resonance

Author(s): Sun, QB (Sun, Qibing); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Wang, ZL (Wang, Zhaolu); Han, J (Han, Jing); Li, SP (Li, Shaopeng)

Source: SCIENTIFIC REPORTS  Volume: 5  Article Number: 16183  DOI: 10.1038/srep16183  Published: NOV 4 2015  

Abstract: We propose a novel scheme for restoring pulse and high noisy images using stochastic resonance, which is based on the modulation instability and provides a cross-correlation gain higher than 8. As opposed to previously reported designs, this unique approach employs a continuous noise and pulse signal for the generation of modulation instability. The visibility and quality of output images can be improved by appropriately adjusting the system parameters. This provides a simple and feasible method for detecting low-level or hidden pulse images in various imaging applications.

Accession Number: WOS:000364091900001

PubMed ID: 26530885

Author Identifiers:

ISSN: 2045-2322

Record 29 of 243

Title: WS₂/fluorine mica (FM) saturable absorbers for all-normal-dispersion mode-locked fiber laser

Author(s): Li, L (Li, Lu); Jiang, SZ (Jiang, Shouzhen); Wang, YG (Wang, Yonggang); Wang, X (Wang, Xi); Duan, LN (Duan, Lina); Mao, D (Mao, Dong); Li, Z (Li, Zhen); Man, BY (Man, Baoyuan); Si, JH (Si, Jinhai)

Source: OPTICS EXPRESS  Volume: 23  Issue: 22  Pages: 28698-28706  DOI: 10.1364/OE.23.028698  Published: NOV 2 2015  

Abstract: The report firstly propose a new WS2 absorber based on fluorine mica (FM) substrate. The WS2 material was fabricated by thermal decomposition method. The FM was stripped into one single layer as thin as 20 mu m and deposited WS2 on it, which can be attached to the fiber flank without causing the laser deviation. Similar to quartz, the transmission rate of FM is as high as 90% at near infrared wavelength from one to two micrometers. Furthermore, FM is a highly elastic material so that it is not easy to break off even its thickness was only 20 mu m. On the contrary, quartz is hard to be processed and easy to break off when its thickness is less than 100 mu m. Compared to organic matrix such as polyvinyl alcohol (PVA), FM has higher softening temperature, heat dissipation and laser damage threshold than those of organic composites. In our work, the modulation depth (MD) and non-saturable losses (NLs) of this kind of saturable absorber were measured to be 5.8% and 14.8%, respectively. The WS2/FM absorber has a high damage threshold of 406 MW/cm(2), two times higher than that of WS2/PVA. By incorporating the saturable absorber into Yb-doped fiber laser cavity, a mode-locked fiber laser was achieved with central wavelength of 1052.45 nm. The repetition rate was 23.26 MHz and the maximum average output power was 30 mW. The long term stability of working was proved to be good too. The results indicate that WS2/FM film is a practical nonlinear optical material for photonic applications. (C) 2015 Optical Society of America

Accession Number: WOS:000366578900058

PubMed ID: 26561138

Author Identifiers:

ISSN: 1094-4087

Record 30 of 243

Title: Relevance Preserving Projection and Ranking for Web Image Search Reranking

Author(s): Ji, Z (Ji, Zhong); Pang, YW (Pang, Yanwei); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON IMAGE PROCESSING  Volume: 24  Issue: 11  Pages: 4137-4147  DOI: 10.1109/TIP.2015.2437198  Published: NOV 2015  

Abstract: An image search reranking (ISR) technique aims at refining text-based search results by mining images' visual content. Feature extraction and ranking function design are two key steps in ISR. Inspired by the idea of hypersphere in one-class classification, this paper proposes a feature extraction algorithm named hypersphere-based relevance preserving projection (HRPP) and a ranking function called hypersphere-based rank (H-Rank). Specifically, an HRPP is a spectral embedding algorithm to transform an original high-dimensional feature space into an intrinsically low-dimensional hypersphere space by preserving the manifold structure and a relevance relationship among the images. An H-Rank is a simple but effective ranking algorithm to sort the images by their distances to the hypersphere center. Moreover, to capture the user's intent with minimum human interaction, a reversed k-nearest neighbor (KNN) algorithm is proposed, which harvests enough pseudorelevant images by requiring that the user gives only one click on the initially searched images. The HRPP method with reversed KNN is named one-click-based HRPP (OC-HRPP). Finally, an OC-HRPP algorithm and the H-Rank algorithm form a new ISR method, H-reranking. Extensive experimental results on three large real-world data sets show that the proposed algorithms are effective. Moreover, the fact that only one relevant image is required to be labeled makes it has a strong practical significance.

Accession Number: WOS:000359563500010

PubMed ID: 26011885

Author Identifiers:

ISSN: 1057-7149

eISSN: 1941-0042

Record 31 of 243

Title: Event-Based Media Enrichment Using an Adaptive Probabilistic Hypergraph Model

Author(s): Liu, XL (Liu, Xueliang); Wang, M (Wang, Meng); Yin, BC (Yin, Bao-Cai); Huet, B (Huet, Benoit); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 45  Issue: 11  Pages: 2461-2471  DOI: 10.1109/TCYB.2014.2374755  Published: NOV 2015  

Abstract: Nowadays, with the continual development of digital capture technologies and social media services, a vast number of media documents are captured and shared online to help attendees record their experience during events. In this paper, we present a method combining semantic inference and multimodal analysis for automatically finding media content to illustrate events using an adaptive probabilistic hypergraph model. In this model, media items are taken as vertices in the weighted hypergraph and the task of enriching media to illustrate events is formulated as a ranking problem. In our method, each hyperedge is constructed using the K-nearest neighbors of a given media document. We also employ a probabilistic representation, which assigns each vertex to a hyperedge in a probabilistic way, to further exploit the correlation among media data. Furthermore, we optimize the hypergraph weights in a regularization framework, which is solved as a second-order cone problem. The approach is initiated by seed media and then used to rank the media documents using a transductive inference process. The results obtained from validating the approach on an event dataset collected from EventMedia demonstrate the effectiveness of the proposed approach.

Accession Number: WOS:000363233000008

PubMed ID: 26470061

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 32 of 243

Title: Development of intelligent control system for X-ray streak camera in diagnostic instrument manipulator

Author(s): Pei, CQ (Pei, Chengquan); Wu, SL (Wu, Shengli); Tian, JS (Tian, Jinshou); Liu, Z (Liu, Zhen); Fang, YM (Fang, Yuman); Gao, GL (Gao, Guilong); Liang, LL (Liang, Lingliang); Wen, WL (Wen, Wenlong)

Source: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT  Volume: 799  Pages: 124-131  DOI: 10.1016/j.nima.2015.07.049  Published: NOV 1 2015  

Abstract: An intelligent control system for an X ray streak camera in a diagnostic instrument manipulator (DIM) is proposed and implemented, which can control time delay, electric focusing, image gain adjustment, switch of sweep voltage, acquiring environment parameters etc. The system consists of 16 A/D converters and 16 D/A converters, a 32-channel general purpose input/output (GPIO) and two sensors. An isolated DC/DC converter with multi-outputs and a single mode filer were adopted to reduce the interference generated by the common ground among the A/D, D/A and I/O. The software was designed using graphical programming language and can remotely access the corresponding instrument from a website. The entire intelligent control system can acquire the desirable data at a speed of 30 Mb/s and store 11 for later analysis. The intelligent. system was implemented on a streak camera in a DIM and it shows a temporal resolution of 11.25 ps, spatial distortion of less than 10% and dynamic range of 279:1. The intelligent control system has been successfully used in a streak camera to verify the synchronization of multi-channel laser on the Confinement Fusion (C) 2015 Elsevier B.V. All rights reserved.

Accession Number: WOS:000361877300019

Author Identifiers:

ISSN: 0168-9002

eISSN: 1872-9576

Record 33 of 243

Title: High-Pulse-Energy All-Normal-Dispersion Yb-Doped Fiber Laser Based on Nonlinear Polarization Evolution

Author(s): Wang, JL (Wang Jun-Li); Wang, XL (Wang Xue-Ling); He, BR (He Bo-Rong); Wang, YG (Wang Yong-Gang); Zhu, JF (Zhu Jiang-Feng); Wei, ZY (Wei Zhi-Yi)

Source: CHINESE PHYSICS LETTERS  Volume: 32  Issue: 11  Article Number: 114202  DOI: 10.1088/0256-307X/32/11/114202  Published: NOV 2015  

Abstract: We report an all-normal-dispersion ytterbium fiber laser mode locked by nonlinear polarization evolution. With a 347-m-long all-fiber ring cavity, a pulse energy of 263 nJ at a repetition rate of 613 kHz is achieved, which is the highest per-pulse energy directly obtained from an all-fiber mode-locked laser doped by ytterbium ions. The compact and operation-robust laser yields a well-shaped spectrum centered at 1032nm with a bandwidth (FWHM) of 4 nm, and the slope efficiency is as high as 27.5%. The proposed low-repetition-rate high-pulse-energy mode-locked fiber laser will be a promising seed for all-fiber chirped pulsed amplification systems.

Accession Number: WOS:000365178900012

Author Identifiers:

ISSN: 0256-307X

eISSN: 1741-3540

Record 34 of 243

Title: Compact multi-band fluorescent microscope with an electrically tunable lens for autofocusing

Author(s): Wang, ZJ (Wang, Zhaojun); Lei, M (Lei, Ming); Yao, BL (Yao, Baoli); Cai, Y (Cai, Yanan); Liang, YS (Liang, Yansheng); Yang, YL (Yang, Yanlong); Yang, XB (Yang, Xibin); Li, H (Li, Hui); Xiong, DX (Xiong, Daxi)

Source: BIOMEDICAL OPTICS EXPRESS  Volume: 6  Issue: 11  Pages: 4353-4364  DOI: 10.1364/BOE.6.004353  Published: NOV 1 2015  

Abstract: Autofocusing is a routine technique in redressing focus drift that occurs in time-lapse microscopic image acquisition. To date, most automatic microscopes are designed on the distance detection scheme to fulfill the autofocusing operation, which may suffer from the low contrast of the reflected signal due to the refractive index mismatch at the water/glass interface. To achieve high autofocusing speed with minimal motion artifacts, we developed a compact multi-band fluorescent microscope with an electrically tunable lens (ETL) device for autofocusing. A modified searching algorithm based on equidistant scanning and curve fitting is proposed, which no longer requires a single-peak focus curve and then efficiently restrains the impact of external disturbance. This technique enables us to achieve an autofocusing time of down to 170 ms and the reproductivity of over 97%. The imaging head of the microscope has dimensions of 12 cm x 12 cm x 6 cm. This portable instrument can easily fit inside standard incubators for real-time imaging of living specimens. (C) 2015 Optical Society of America

Accession Number: WOS:000366122400015

PubMed ID: 26601001

Author Identifiers:

ISSN: 2156-7085

Record 35 of 243

Title: Research progress of chelate precursor doping method to fabricate Yb-doped large-mode-area silica fibers for kW-level laser

Author(s): Wang, Z (Wang, Zhen); Zhan, H (Zhan, Huan); Ni, L (Ni, Li); Peng, K (Peng, Kun); Wang, XL (Wang, Xiaolong); Wang, JJ (Wang, Jianjun); Jing, F (Jing, Feng); Lin, AX (Lin, Aoxiang)

Source: LASER PHYSICS  Volume: 25  Issue: 11  Article Number: 115103  DOI: 10.1088/1054-660X/25/11/115103  Published: NOV 2015  

Abstract: With continuous efforts and practical managing experiences, the chelate precursor doping method has been justified as an effective way to dope rare-earth ions into silica host materials, a key technique in making large-mode-area silica fibers for high power laser applications. It is characterized by good controllability, stability and repeatability to accomplish different refractive index profiles. Different preforms with a large core, designed refractive index profile, good symmetrical shape and homogeneous elemental distribution were successfully fabricated. The home-made standard 20/400-type double-cladding Yb-doped large-mode-area silica fiber was drawn and presented a 1.6 kW laser output at 1064 nm, the highest power record publically reported with this method. With further optimization, chelate precusor doping method has potential to manufacture high power laser fibers for the next generation.

Accession Number: WOS:000365350800004

Author Identifiers:

ISSN: 1054-660X

eISSN: 1555-6611

Record 36 of 243

Title: Panoramic camera on the Yutu lunar rover of the Chang'e-3 mission

Author(s): Yang, JF (Yang, Jian-Feng); Li, CL (Li, Chun-Lai); Xue, B (Xue, Bin); Ruan, P (Ruan, Ping); Gao, W (Gao, Wei); Qiao, WD (Qiao, Wei-Dong); Lu, D (Lu, Di); Ma, XL (Ma, Xiao-Long); Li, F (Li, Fu); He, YH (He, Ying-Hong); Li, T (Li, Ting); Ren, X (Ren, Xin); Yan, XT (Yan, Xing-Tao)

Source: RESEARCH IN ASTRONOMY AND ASTROPHYSICS  Volume: 15  Issue: 11  Pages: 1867-1880  DOI: 10.1088/1674-4527/15/11/009  Published: NOV 2015  

Abstract: The Chang'e-3 panoramic camera, which is composed of two cameras with identical functions, performances and interfaces, is installed on the lunar rover mast. It can acquire 3D images of the lunar surface based on the principle of binocular stereo vision. By rotating and pitching the mast, it can take several photographs of the patrol area. After stitching these images, panoramic images of the scenes will be obtained. Thus the topography and geomorphology of the patrol area and the impact crater, as well as the geological structure of the lunar surface, will be analyzed and studied. In addition, it can take color photographs of the lander using the Bayer color coding principle. It can observe the working status of the lander by switching between static image mode and dynamic video mode with automatic exposure time. The focal length of the lens on the panoramic camera is 50 mm and the field of view is 19.7 degrees x 14.5 degrees. Under the best illumination and viewing conditions, the largest signal-to-noise ratio of the panoramic camera is 44 dB. Its static modulation transfer function is 0.33. A large number of ground testing experiments and on-orbit imaging results show that the functional interface of the panoramic camera works normally. The image quality of the panoramic camera is satisfactory. All the performance parameters of the panoramic camera satisfy the design requirements.

Accession Number: WOS:000365467400009

Author Identifiers:

ISSN: 1674-4527

Record 37 of 243

Title: Optical properties of a binuclear neodymium complex in phosphorus oxychloride for liquid laser

Author(s): Zhang, GF (Zhang, Guofang); She, JB (She, Jiangbo); Han, K (Han, Kai); Nie, RZ (Nie, Rongzhi); Li, DD (Li, Dongdong); Peng, B (Peng, Bo)

Source: OPTICAL MATERIALS  Volume: 49  Pages: 343-347  DOI: 10.1016/j.optmat.2015.10.002  Published: NOV 2015  

Abstract: A novel binuclear neodymium complex Nd(CF3COO)(3)center dot(Ph3PO)(2) (Ph3PO: triphenylphosphine oxide) with high stimulated emission cross-section was presented. The molecular structure of the complex was characterized by single-crystal X-ray diffraction. The optical properties of the complex in liquid medium were studied. From the absorption and luminescence spectra, the Judd-Ofelt parameters of Nd (CF3COO)(3)center dot(Ph3PO)(2) in phosphorus oxychloride were obtained. Based on the crystal structure, the effects of crystal field and bonding valence properties on three intensity parameters Omega(t)(t = 2, 4, 6) and emission cross-section were analyzed in detail. The emission cross-section of E-4(3/2) -> I-4(11/2) fluorescence transition (2.78 x 10(-2) cm(2)) of the new neodymium compound was higher than those of other Nd(III) complexes and even comparable with some laser glasses. (C) 2015 Elsevier BM. All rights reserved.

Accession Number: WOS:000364255100054

Author Identifiers:

ISSN: 0925-3467

eISSN: 1873-1252

Record 38 of 243

Title: Robust Visual Tracking Using Structurally Random Projection and Weighted Least Squares

Author(s): Zhang, SP (Zhang, Shengping); Zhou, HY (Zhou, Huiyu); Jiang, F (Jiang, Feng); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY  Volume: 25  Issue: 11  Pages: 1749-1760  DOI: 10.1109/TCSVT.2015.2406194  Published: NOV 2015  

Abstract: Sparse representation-based visual tracking approaches have attracted increasing interests in the community in recent years. The main idea is to linearly represent each target candidate using a set of target and trivial templates, while imposing a sparsity constraint onto the representation coefficients. After we obtain the coefficients using l(1)-norm minimization methods, the candidate with the lowest error, when it is reconstructed using only the target templates and the associated coefficients, is considered as the tracking result. In spite of promising system performance widely reported, it is unclear if the performance of these trackers can be maximized. In addition, computational complexity caused by the dimensionality of the feature space limits these algorithms in real-time applications. In this paper, we propose a real-time visual tracking method based on structurally random projection (RP) and weighted least squares (WLS) techniques. In particular, to enhance the discriminative capability of the tracker, we introduce background templates to the linear representation framework. To handle appearance variations over time, we relax the sparsity constraint using a WLS method to obtain the representation coefficients. To further reduce the computational complexity, structurally RP is used to reduce the dimensionality of the feature space, while preserving the pairwise distances between the data points in the feature space. Experimental results show that the proposed approach outperforms several state-of-the-art tracking methods.

Accession Number: WOS:000364230600003

Author Identifiers:

ISSN: 1051-8215

eISSN: 1558-2205

Record 39 of 243

Title: In situ optical measurements of Chang'E-3 landing site in Mare Imbrium: 2. Photometric properties of the regolith

Author(s): Jin, WD (Jin, Weidong); Zhang, H (Zhang, Hao); Yuan, Y (Yuan, Ye); Yang, YZ (Yang, Yazhou); Shkuratov, YG (Shkuratov, Yuriy G.); Lucey, PG (Lucey, Paul G.); Kaydash, VG (Kaydash, Vadim G.); Zhu, MH (Zhu, Meng-Hua); Xue, B (Xue, Bin); Di, KC (Di, Kaichang); Xu, B (Xu, Bin); Wan, WH (Wan, Wenhui); Xiao, L (Xiao, Long); Wang, ZW (Wang, Ziwei)

Source: GEOPHYSICAL RESEARCH LETTERS  Volume: 42  Issue: 20  Pages: 8312-8319  DOI: 10.1002/2015GL065789  Published: OCT 28 2015  

Abstract: The panorama cameras onboard the Yutu Rover of the Chang'E-3 lunar mission acquired hundreds of high-resolution color images of the lunar surface and captured the first in situ lunar opposition effect (OE) since the Apollo era. We extracted the phase curve and the color ratio in three bands with the phase angle range from 2 degrees to 141 degrees. Photometric inversions using the Hapke model reveal that submicroscopic dusts are present in the landing area and both the coherent backscattering and the shadow hiding are responsible for the strong OE. Compared with spaceborne measurements, the grains in the landing site are brighter, more transparent, and appear to be better crystallized than the average maria basaltic grains. The results show that the phase-reddening effect appears to be present in the in situ phase curves. The current phase curve can be used as the ground-truth validations of any future spaceborne phase curve measurement over the landing site region.

Accession Number: WOS:000364782500007

Author Identifiers:

ISSN: 0094-8276

eISSN: 1944-8007

Record 40 of 243

Title: Multifocus color image sequence fusion based on mean shift segmentation

Author(s): Hao, XX (Hao, Xingxing); Zhao, H (Zhao, Hui); Liu, J (Liu, Jing)

Source: APPLIED OPTICS  Volume: 54  Issue: 30  Pages: 8982-8989  DOI: 10.1364/AO.54.008982  Published: OCT 20 2015  

Abstract: This paper presents a region-based technique for fusion of a multifocus color image sequence in the LUV color space. First, mean shift segmentation was applied on the weighted average image of the image sequence to obtain the fusion reference areas. Second, for each segmented area, the well-known modified Laplacian (LAP2) was used as a focus measure to select the clearest parts within the image sequence and then a final image focused with all parts can be generated. Mutual information, QAB/F metric, entropy, standard deviation, image sharpness metric, image contrast metric, average gradient, and spatial frequency were adopted to assess the quality of the fused image. Experiments carried out using standard image sequences from HeliconSoft demonstrated that the results obtained through our technique offer good performance. The proposed technique can be used to extend the depth of field (DOF) of a camera system effectively. (C) 2015 Optical Society of America

Accession Number: WOS:000363311400024

PubMed ID: 26560388

ISSN: 1559-128X

eISSN: 2155-3165

Record 41 of 243

Title: Picosecond resolving detection method and experiment for ultrafast X-ray by modulation of an optical probe

Author(s): Wang, B (Wang Bo); Bai, YL (Bai Yong-Lin); Cao, WW (Cao Wei-Wei); Xu, P (Xu Peng); Liu, BY (Liu Bai-Yu); Gou, YS (Gou Yong-Sheng); Zhu, BL (Zhu Bing-Li); Hou, X (Hou Xun)

Source: ACTA PHYSICA SINICA  Volume: 64  Issue: 20  Article Number: 200701  DOI: 10.7498/aps.64.200701  Published: OCT 20 2015  

Abstract: Diagnostic measurement of single picosecond event in high energy density physics, laser fusion, plasma radiation, and combustion, is of great importance. However, the measuring of the shape of the single X-ray pulse and the synchronization of X-ray and the laser pulse in picosecond resolution is still a great challenge. Restricted by the transit time of electrons, the time-resolution limit of a conventional framing camera based on the microchannel plate is 40 ps. Centered on the full-optical modulation effect of the light-probe, a novel method for X-ray detection of picoseconds temporal resolution based on low temperature GaAs is proposed in this work. The basic physical mechanism of the detector can be explained in both macroscopical and microcosmic ways. In the macroscopical way, the X-ray radiation absorption in the sensor material produces a transient, non-equilibrium electron-hole pair distribution that results in a transient differential change of the local refractive index, which is then sensed by the reflectivity changes of the optical probe beam. In the microcosmic way, X-ray absorption creates photoelectrons and the core level holes are subsequently filled through Auger or fluorescence processes. These excitations ultimately increase conduction and valence band carriers that perturb optical reflectivity.
To verify the proposed X-ray detection method, a Fabry-Perot detector is designed, which consists of a 5 mu m thick GaAs layer surrounded by a GaAs/AlAs distributed Bragg reflector. The test is carried out on a femtosecond laser facility, where the X-ray source is produced by focusing the 56 fs Ti: Sapphire facility laser, with a central wavelength of 800 nm, onto an aluminum foil. Then the X-ray pulse induces a transient optical reflectivity change in GaAs, which is a powerful tool for establishing the high-speed X-ray detection.
The experimental results indicate that this technology can be used to provide X-ray detectors with a temporal resolution of tens of picoseconds. By optimizing the material, the temporal resolution can be enhanced to be less than 1 ps. Through further development, this X-ray detector could provide an insight into previously unmeasurable phenomena in many fields. Future work will focus on developing much faster devices characterizing both the rise and fall time and imaging array technology.

Accession Number: WOS:000368822000009

Author Identifiers:

ISSN: 1000-3290

Record 42 of 243

Title: Direct welding of glass and metal by 1 kHz femtosecond laser pulses

Author(s): Zhang, GD (Zhang, Guodong); Cheng, GH (Cheng, Guanghua)

Source: APPLIED OPTICS  Volume: 54  Issue: 30  Pages: 8957-8961  DOI: 10.1364/AO.54.008957  Published: OCT 20 2015  

Abstract: In the welding process between similar or dissimilar materials, inserting an intermediate layer and pressure assistance are usually thought to be necessary. In this paper, the direct welding between alumina-silicate glass and metal (aluminum, copper, and steel), under exposure from 1 kHz femtosecond laser pulses without any auxiliary processes, is demonstrated. The micron/nanometer-sized metal particles induced by laser ablation were considered to act as the adhesive in the welding process. The welding parameters were optimized by varying the pulse energy and the translation velocity of the sample. The shear joining strength characterized by a shear force testing equipment was as high as 2.34 MPa. This direct bonding technology has potential for applications in medical devices, sensors, and photovoltaic devices. (C) 2015 Optical Society of America

Accession Number: WOS:000363311400021

PubMed ID: 26560385

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 43 of 243

Title: WS₂ saturable absorber for dissipative soliton mode locking at 1.06 and 1.55 μm

Author(s): Mao, D (Mao, Dong); Zhang, SL (Zhang, Shengli); Wang, YD (Wang, Yadong); Gan, XT (Gan, Xuetao); Zhang, WD (Zhang, Wending); Mei, T (Mei, Ting); Wang, YG (Wang, Yonggang); Wang, YS (Wang, Yishan); Zeng, HB (Zeng, Haibo); Zhao, JL (Zhao, Jianlin)

Source: OPTICS EXPRESS  Volume: 23  Issue: 21  Pages: 27509-27519  DOI: 10.1364/OE.23.027509  Published: OCT 19 2015  

Abstract: Transition-metal dichalcogenides, such as tungsten disulfide (WS2) and molybdenium disulfide (MoS2), are highly anisotropic layered materials and have attracted growing interest from basic research to practical applications due to their exotic physical property that may complement graphene and other semiconductor materials. WS2 nanosheets are found to exhibit broadband nonlinear saturable absorption property, and saturable absorbers (SAs) are fabricated by depositing WS2 nanosheets on side-polished fibers. Attributing to the weak evanescent field and long interaction length, the WS2 nanosheets are not exposed to large optical intensity, which allows the SA to work at the high-power regime. The SAs are used to mode lock erbium- and ytterbium-doped fiber lasers with normal dispersion, producing trains of dissipative soliton at 1.55 and 1.06 mu m respectively. Simulations show that the bandgap of WS2 nanosheets decreases from 1.18 to 0.02 and 0.65 eV by introducing W and S defects respectively, which may contribute to the broadband saturable absorption property of the WS2. (C) 2015 Optical Society of America

Accession Number: WOS:000366574400062

PubMed ID: 26480411

Author Identifiers:

ISSN: 1094-4087

Record 44 of 243

Title: Transparent and Dense Ladder-Like Alkylene-Bridged Polymethylsiloxane Coating with Enhanced Water Vapor Barrier Property

Author(s): Zhang, C (Zhang, Ce); Zhang, C (Zhang, Cong); Cui, XM (Cui, Xinmin); Sun, JH (Sun, Jinghua); Ding, RM (Ding, Ruimin); Zhang, QH (Zhang, Qinghua); Xu, Y (Xu, Yao)

Source: ACS APPLIED MATERIALS & INTERFACES  Volume: 7  Issue: 40  Pages: 22157-22165  DOI: 10.1021/acsami.5b08084  Published: OCT 14 2015  

Abstract: Organic-inorganic hybrid composites have been well-studied as water vapor barrier materials for their long diffusion length of water vapor in coatings which can be realized by improving the aspect ratio of inorganic components and regularity of nanostructure in coatings. In this paper, dense organic-inorganic hybrid coating based on ladder-like alkylene-bridged polymethylsiloxane (ABPMS) was successfully fabricated through the hydrosilylation reaction between polymethylhydrosiloxane and diene (1,5-hexadiene or 1,7-octadiene) in toluene under Pt/C catalysis. Its ladder-like structure was verified by Si-29 magic angle spinning (MAS) NMR, C-18 MAS NMR, and in-plane and out-of-plane glance-incident X-ray diffraction (GIXRD) techniques. Its corresponding coating showed excellent water vapor barrier ability for a typical water-soluble crystal, potassium dihydrogen phosphate (KDP). When treated in 50% relative humidity (RH) condition at 25 degrees C for 8 months, the ABPMS coating with 100 run thickness displayed a very low transmittance loss of 1.6% compared with the high transmittance loss of 10% for uncoated KDP. Moreover, the ABPMS coating showed good ultraviolet radiation resistance, thermal stability, low mechanical property, and excellent compatibility with hydrophobic antireflective (AR) coatings.

Accession Number: WOS:000363001500006

PubMed ID: 26393288

Author Identifiers:

ISSN: 1944-8244

Record 45 of 243

Title: Digital holographic shape measurement using Fizeau microscopy

Author(s): Abdelsalam, DG (Abdelsalam, D. G.); Min, JW (Min, Junwei); Kim, D (Kim, Daesuk); Yao, BL (Yao, Baoli)

Source: CHINESE OPTICS LETTERS  Volume: 13  Issue: 10  Article Number: 100701  DOI: 10.3788/COL201513.100701  Published: OCT 10 2015