Record 1 of 223

Title: Generation of high-energy and broadband terahertz radiation via coherent synthesis

Author(s): Li, SP (Li, Shaopeng); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Sun, QB (Sun, Qibing)

Source: JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS  Volume: 46  Issue: 24  Article Number: 245402  DOI: 10.1088/0953-4075/46/24/245402  Published: DEC 28 2013  

Abstract: A new method for the generation of high-energy and broadband terahertz (THz) radiation via coherent synthesis from multiple optical rectifications has been proposed. It is found that the intensities of the synthesized THz pulse are proportional to the square of the number of optical rectification processes when the same nonlinear crystals are used, which provides a simple method for the scaling up of THz energies with a powerful femtosecond laser. This method presents the possibility for THz strong-field physics with this table-top THz source. Moreover, in order to ensure that all the spectral components of the THz pulses are coherently synthesized, the relative time delay among the pump pulses should be less than 0.22 T-0 (T-0 is the pump pulse width).

Accession Number: WOS:000328275700013

Author Identifiers:

ISSN: 0953-4075

eISSN: 1361-6455

Record 2 of 223

Title: Face recognition using Weber local descriptors

Author(s): Li, ST (Li, Shutao); Gong, DY (Gong, Dayi); Yuan, Y (Yuan, Yuan)

Source: NEUROCOMPUTING  Volume: 122  Special Issue: SI  Pages: 272-283  DOI: 10.1016/j.neucom.2013.05.038  Published: DEC 25 2013  

Abstract: This paper presents a method for face recognition using multi-scale Weber local descriptors (WLDs) and multi-level information fusion. Our method introduces the WLD, a novel and robust local descriptor, to describe the facial images and modifies it by a non-linear quantization approach to enhance its discriminative power. Moreover, a multi-scale framework for WLD extraction with multi-level information fusion approaches is provided for face representation and recognition. The proposed method has four main steps: (1) image partition: under given rules, each facial image is uniformly divided into a set of non-overlapped sub-regions; in this way, for a set of facial images, we therefore have a large pool of this type of sub-regions; (2) feature extraction: in this pool of sub-regions, taking one sub-region as a center, a group of similar ones are chosen for extraction of WLD histogram features; (3) features measurement: these WLD histograms are then fused into a single vector as the feature of the center sub-region. Nearest neighborhood on chi-square is employed for similarity measurement between two sub-regions; and (4) voting: the recognition result of the entire probe (a face in sub-regions) is obtained via a voting function on the recognition result of all its sub-regions. Experimental results demonstrate the effectiveness of the proposed method upon three popular datasets. (C) 2013 Elsevier B.V. All rights reserved.

Accession Number: WOS:000325590200030

Author Identifiers:

ISSN: 0925-2312

eISSN: 1872-8286

Record 3 of 223

Title: Subwavelength multiple focal spots produced by tight focusing the patterned vector optical fields

Author(s): Cai, MQ (Cai, Mengqiang); Tu, CH (Tu, Chenghou); Zhang, HH (Zhang, Huihui); Qian, SX (Qian, Shengxia); Lou, K (Lou, Kai); Li, YN (Li, Yongnan); Wang, HT (Wang, Hui-Tian)

Source: OPTICS EXPRESS  Volume: 21  Issue: 25  Pages: 31469-31482  DOI: 10.1364/OE.21.031469  Published: DEC 16 2013  

Abstract: We numerically and experimentally explored generation and regulation of subwavelength multiple focal spots produced by tight focusing patterned vector optical fields (PVOFs). We presented a modified Richard-Wolf diffraction integration method suitable for the tight focusing of the PVOFs. By tailoring the spatial geometry and the polarization distributions of the PVOFs, simulations show that the diverse spatial configurations of subwavelength multiple focal spots can be achieved. To verify our idea, we experimentally generated the theoretically calculated examples of femtosecond PVOFs, then tightly focused them on the surface of the crystalline silicon wafers, and finally characterized the morphologies of modified surfaces. The SEM (scanning electronic microscopy) images confirmed that the experimental results are in good agreement with the simulations. Based on the diverse controlling degrees of freedom of PVOFs, the resultant subwavelength focal fields are flexible and powerful in parallel processing, optical manipulation and so on. (C) 2013 Optical Society of America

Accession Number: WOS:000328575700130

PubMed ID: 24514721

Author Identifiers:

ISSN: 1094-4087

Record 4 of 223

Title: Phase retrieval with resolution enhancement by using structured illumination

Author(s): Gao, P (Gao, Peng); Pedrini, G (Pedrini, Giancarlo); Osten, W (Osten, Wolfgang)

Source: OPTICS LETTERS  Volume: 38  Issue: 24  Pages: 5204-5207  DOI: 10.1364/OL.38.005204  Published: DEC 15 2013  

Abstract: In this Letter, we present referenceless phase retrieval methods with resolution enhancement. Structured illuminations with different orientations and phase shifts are generated by a spatial light modulator and are used to illuminate the specimen. The generated diffraction patterns are recorded by a CCD camera, and the phase of the wavefront is reconstructed from these patterns. (C) 2013 Optical Society of America

Accession Number: WOS:000328702100002

PubMed ID: 24322218

Author Identifiers:

ISSN: 0146-9592

eISSN: 1539-4794

Record 5 of 223

Title: Universal Blind Image Quality Assessment Metrics Via Natural Scene Statistics and Multiple Kernel Learning

Author(s): Gao, XB (Gao, Xinbo); Gao, F (Gao, Fei); Tao, DC (Tao, Dacheng); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON NEURAL NETWORKS AND LEARNING SYSTEMS  Volume: 24  Issue: 12  Pages: 2013-2026  DOI: 10.1109/TNNLS.2013.2271356  Published: DEC 2013  

Abstract: Universal blind image quality assessment (IQA) metrics that can work for various distortions are of great importance for image processing systems, because neither ground truths are available nor the distortion types are aware all the time in practice. Existing state-of-the-art universal blind IQA algorithms are developed based on natural scene statistics (NSS). Although NSS-based metrics obtained promising performance, they have some limitations: 1) they use either the Gaussian scale mixture model or generalized Gaussian density to predict the nonGaussian marginal distribution of wavelet, Gabor, or discrete cosine transform coefficients. The prediction error makes the extracted features unable to reflect the change in nonGaussianity (NG) accurately. The existing algorithms use the joint statistical model and structural similarity to model the local dependency (LD). Although this LD essentially encodes the information redundancy in natural images, these models do not use information divergence to measure the LD. Although the exponential decay characteristic (EDC) represents the property of natural images that large/small wavelet coefficient magnitudes tend to be persistent across scales, which is highly correlated with image degradations, it has not been applied to the universal blind IQA metrics; and 2) all the universal blind IQA metrics use the same similarity measure for different features for learning the universal blind IQA metrics, though these features have different properties. To address the aforementioned problems, we propose to construct new universal blind quality indicators using all the three types of NSS, i.e., the NG, LD, and EDC, and incorporating the heterogeneous property of multiple kernel learning (MKL). By analyzing how different distortions affect these statistical properties, we present two universal blind quality assessment models, NSS global scheme and NSS two-step scheme. In the proposed metrics: 1) we exploit the NG of natural images using the original marginal distribution of wavelet coefficients; 2) we measure correlations between wavelet coefficients using mutual information defined in information theory; 3) we use features of EDC in universal blind image quality prediction directly; and 4) we introduce MKL to measure the similarity of different features using different kernels. Thorough experimental results on the Laboratory for Image and Video Engineering database II and the Tampere Image Database2008 demonstrate that both metrics are in remarkably high consistency with the human perception, and overwhelm representative universal blind algorithms as well as some standard full reference quality indexes for various types of distortions.

Accession Number: WOS:000326940600009

PubMed ID: 24805219

Author Identifiers:

ISSN: 2162-237X

eISSN: 2162-2388

Record 6 of 223

Title: Off-axis digital holographic microscopy with LED illumination based on polarization filtering

Author(s): Guo, RL (Guo, Rongli); Yao, BL (Yao, Baoli); Gao, P (Gao, Peng); Min, JW (Min, Junwei); Zhou, ML (Zhou, Meiling); Han, J (Han, Jun); Yu, X (Yu, Xun); Yu, XH (Yu, Xianghua); Lei, M (Lei, Ming); Yan, SH (Yan, Shaohui); Yang, YL (Yang, Yanlong); Dan, D (Dan, Dan); Ye, T (Ye, Tong)

Source: APPLIED OPTICS  Volume: 52  Issue: 34  Pages: 8233-8238  DOI: 10.1364/AO.52.008233  Published: DEC 1 2013  

Abstract: A reflection mode digital holographic microscope with light emitting diode (LED) illumination and off-axis interferometry is proposed The setup is comprised of a Linnik interferometer and a grating based 41 imaging unit. Both object and reference waves travel coaxially and are split into multiple diffraction orders in the Fourier plane by the grating. The zeroth and first orders are filtered by a polarizing array to select orthogonally polarized object waves and reference waves. Subsequently, the object and reference waves are combined again in the output plane of the 4f system, and then the hologram with uniform contrast over the entire field of view can be acquired with the aid of a polarizer. The one-shot nature in the off-axis configuration enables an interferometric recording time on a millisecond scale. The validity of the proposed setup is illustrated by imaging nanostructured substrates, and the experimental results demonstrate that the phase noise is reduced drastically by an order of 68% when compared to a He Ne laser-based result. (C) 2013 Optical Society of America

Accession Number: WOS:000328449900009

PubMed ID: 24513823

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 7 of 223

Title: Design of Airborne Dual Channel Ultraviolet-Visible Imaging Spectrometer with Large Field of View, Wide Spectrum, and High Resolution

Author(s): Hao, AH (Hao Ai-hua); Hu, BL (Hu Bing-liang); Bai, JG (Bai Jia-guang); Li, LB (Li Li-bo); Yu, T (Yu Tao); Li, SY (Li Si-yuan)

Source: SPECTROSCOPY AND SPECTRAL ANALYSIS  Volume: 33  Issue: 12  Pages: 3432-3436  DOI: 10.3964/j.issn.1000-0593(2013)12-3432-05  Published: DEC 2013  

Abstract: The ultraviolet-visible (UV-Vis 200 similar to 500 nm) imaging spectrometer is an important part of space remote sensing. Based on special requirements and practical application of the airborne UV-VIS spectrometer, a kind of scanning imaging spectrometer using area array CCD is proposed, which can meet the application requirements of large field of view, wide spectrum and high resolution. It overcomes low spatial resolution of traditional line array CCD scanning imaging spectrometer, and limited field of view of the pushbroom imaging spectrometer. In addition, dual channel was designed to reduce stray light. 400 similar to 500 nm band includes two order spectrum for 200 similar to 250 nm band, and variation of radiance from earth between the shorter wavelength (<290 nm) and the longer wavelength (>310 nm) is above three orders of magnitude. In the structure design of the system, the imaging spectrometer is composed of a two-mirror concentric telescope and two Czerny-Turner plane grating imaging spectrometers. The whole system doesn't use any additional optical elements in addition to spherical mirrors. The whole system has the advantage of simple structure, excellent performance, and very good feasibility. The modulation transfer function value of full spectrum and full field of view is above 0. 6.

Accession Number: WOS:000328710600054

PubMed ID: 24611417

Author Identifiers:

ISSN: 1000-0593

Record 8 of 223

Title: Linear Tracking for 3-D Medical Ultrasound Imaging

Author(s): Huang, QH (Huang, Qing-Hua); Yang, Z (Yang, Zhao); Hu, W (Hu, Wei); Jin, LW (Jin, Lian-Wen); Wei, G (Wei, Gang); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 6  Pages: 1747-1754  DOI: 10.1109/TSMCC.2012.2229270  Published: DEC 2013  

Abstract: As the clinical application grows, there is a rapid technical development of 3-D ultrasound imaging. Compared with 2-D ultrasound imaging, 3-D ultrasound imaging can provide improved qualitative and quantitative information for various clinical applications. In this paper, we proposed a novel tracking method for a freehand 3-D ultrasound imaging system with improved portability, reduced degree of freedom, and cost. We designed a sliding track with a linear position sensor attached, and it transmitted positional data via a wireless communication module based on Bluetooth, resulting in a wireless spatial tracking modality. A traditional 2-D ultrasound probe fixed to the position sensor on the sliding track was used to obtain real-time B-scans, and the positions of the B-scans were simultaneously acquired when moving the probe along the track in a freehand manner. In the experiments, the proposed method was applied to ultrasound phantoms and real human tissues. The results demonstrated that the new system outperformed a previously developed freehand system based on a traditional six-degree-of-freedom spatial sensor in phantom and in vivo studies, indicating its merit in clinical applications for human tissues and organs.

Accession Number: WOS:000327647500020

PubMed ID: 23757592

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 9 of 223

Title: Passively harmonic mode locking in ytterbium-doped fiber laser with graphene oxide saturable absorber

Author(s): Li, HQ (Li, Huiquan); Wang, YG (Wang, Yonggang); Yan, PG (Yan, Peiguang); Cao, GZ (Cao, Guangzhong); Zhao, JQ (Zhao, Junqing); Zhang, GL (Zhang, Gelin); Huang, SS (Huang, Shisheng); Lin, RY (Lin, Rongyong)

Source: OPTICAL ENGINEERING  Volume: 52  Issue: 12  Article Number: 126102  DOI: 10.1117/1.OE.52.12.126102  Published: DEC 2013  

Abstract: We have demonstrated the dissipative solitons generated in an ytterbium-doped fiber laser cavity using graphene oxide as the saturable absorber. The lasing light, centered at 1077.2 nm, has a 3 dB spectral bandwidth of similar to 1.12 nm. Under different launched pump powers and appropriate polarization orientations, harmonic mode-locked of second-and third-order pulse trains have been achieved; the corresponding 3-dB bandwidth and pulse duration have been detected. (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, including its DOI.

Accession Number: WOS:000329525800016

Author Identifiers:

ISSN: 0091-3286

eISSN: 1560-2303

Record 10 of 223

Title: Learning Discriminative Key Poses for Action Recognition

Author(s): Liu, L (Liu, Li); Shao, L (Shao, Ling); Zhen, XT (Zhen, Xiantong); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 6  Pages: 1860-1870  DOI: 10.1109/TSMCB.2012.2231959  Published: DEC 2013  

Abstract: In this paper, we present a new approach for human action recognition based on key-pose selection and representation. Poses in video frames are described by the proposed extensive pyramidal features (EPFs), which include the Gabor, Gaussian, and wavelet pyramids. These features are able to encode the orientation, intensity, and contour information and therefore provide an informative representation of human poses. Due to the fact that not all poses in a sequence are discriminative and representative, we further utilize the AdaBoost algorithm to learn a subset of discriminative poses. Given the boosted poses for each video sequence, a new classifier named weighted local naive Bayes nearest neighbor is proposed for the final action classification, which is demonstrated to be more accurate and robust than other classifiers, e.g., support vector machine (SVM) and naive Bayes nearest neighbor. The proposed method is systematically evaluated on the KTH data set, the Weizmann data set, the multiview IXMAS data set, and the challenging HMDB51 data set. Experimental results manifest that our method outperforms the state-of-the-art techniques in terms of recognition rate.

Accession Number: WOS:000327647500029

PubMed ID: 23757577

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 11 of 223

Title: Spectral Segmentation via Midlevel Cues Integrating Geodesic and Intensity

Author(s): Lu, HC (Lu, Huchuan); Zhang, RX (Zhang, Ruixuan); Li, SF (Li, Shifeng); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 6  Pages: 2170-2178  DOI: 10.1109/TCYB.2013.2243432  Published: DEC 2013  

Abstract: Image segmentation still remains as a challenge in image processing and pattern recognition when involving complex natural scenes. In this paper, we present a new affinity model for spectral segmentation based on midlevel cues. In contrast to most existing methods that operate directly on low-level cues, we first oversegment the image into superpixel images and then integrate the geodesic line edge and intensity cue to form the similarity matrix W so that it more accurately describes the similarity between data. The geodesic line edge could avoid strong boundary and represent the true boundary between two superpixels while the mean red green blue vector could describe the intensity of superpixels better. As far as we know, this is a totally new kind of affinity model to represent superpixels. Based on this model, we use the spectral clustering in the superpixel level and then achieve the image segmentation in the pixel level. The experimental results show that the proposed method performs steadily and well on various natural images. The evaluation comparisons also prove that our method achieves comparable accuracy and significantly performs better than most state-of-the-art algorithms.

Accession Number: WOS:000327647500054

PubMed ID: 23757526

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 12 of 223

Title: Image Super-Resolution via Double Sparsity Regularized Manifold Learning

Author(s): Lu, XQ (Lu, Xiaoqiang); Yuan, Y (Yuan, Yuan); Yan, PK (Yan, Pingkun)

Source: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY  Volume: 23  Issue: 12  Pages: 2022-2033  DOI: 10.1109/TCSVT.2013.2244798  Published: DEC 2013  

Abstract: Over the past few years, high resolutions have been desirable or essential, e. g., in online video systems, and therefore, much has been done to achieve an image of higher resolution from the corresponding low-resolution ones. This procedure of recovering/rebuilding is called single-image super-resolution (SR). Performance of image SR has been significantly improved via methods of sparse coding. That is to say, the image frame patch can be sparse linear combinations of basis elements. However, most of these existing methods fail to consider the local geometrical structure in the space of the training data. To take this crucial issue into account, this paper proposes a method named double sparsity regularized manifold learning (DSRML). DSRML can preserve the properties of the aforementioned local geometrical structure by employing manifold learning, e. g., locally linear embedding. Based on a large amount of experimental results, DSRML is demonstrated to be more robust and more effective than previous efforts in the task of single-image SR.

Accession Number: WOS:000328047000002

Author Identifiers:

ISSN: 1051-8215

eISSN: 1558-2205

Record 13 of 223

Title: LDFT-Based Watermarking Resilient to Local Desynchronization Attacks

Author(s): Tian, HW (Tian, Huawei); Zhao, Y (Zhao, Yao); Ni, RR (Ni, Rongrong); Qin, LM (Qin, Lunming); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 6  Pages: 2190-2201  DOI: 10.1109/TCYB.2013.2245415  Published: DEC 2013  

Abstract: Up to now, a watermarking scheme that is robust against desynchronization attacks (DAs) is still a grand challenge. Most image watermarking resynchronization schemes in literature can survive individual global DAs (e.g., rotation, scaling, translation, and other affine transforms), but few are resilient to challenging cropping and local DAs. The main reason is that robust features for watermark synchronization are only globally invariable rather than locally invariable. In this paper, we present a blind image watermarking resynchronization scheme against local transform attacks. First, we propose a new feature transform named local daisy feature transform (LDFT), which is not only globally but also locally invariable. Then, the binary space partitioning (BSP) tree is used to partition the geometrically invariant LDFT space. In the BSP tree, the location of each pixel is fixed under global transform, local transform, and cropping. Lastly, the watermarking sequence is embedded bit by bit into each leaf node of the BSP tree by using the logarithmic quantization index modulation watermarking embedding method. Simulation results show that the proposed watermarking scheme can survive numerous kinds of distortions, including common image-processing attacks, local and global DAs, and noninvertible cropping.

Accession Number: WOS:000327647500056

PubMed ID: 23757528

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 14 of 223

Title: Multi-spectral dataset and its application in saliency detection

Author(s): Wang, Q (Wang, Qi); Zhu, GK (Zhu, Guokang); Yuan, Y (Yuan, Yuan)

Source: COMPUTER VISION AND IMAGE UNDERSTANDING  Volume: 117  Issue: 12  Pages: 1748-1754  DOI: 10.1016/j.cviu.2013.07.002  Published: DEC 2013  

Abstract: Saliency detection has been researched a lot in recent years. Traditional methods are mostly conducted and evaluated on conventional RGB images. Few work has considered the incorporation of multi-spectral clues. Considering the success of including near-infrared spectrum in applications such as face recognition and scene categorization, this paper presents a multi-spectral dataset and applies it in saliency detection. Experiments demonstrate that the incorporation of near-infrared band is effective in the saliency detection procedure. We also test the combinational models for integrating visible and near-infrared bands. Results show that there is no single model to effect on every saliency detection method. Models should be selected according to the specific employed method. (C) 2013 Elsevier Inc. All rights reserved.

Accession Number: WOS:000326136600010

Author Identifiers:

ISSN: 1077-3142

eISSN: 1090-235X

Record 15 of 223

Title: Joint Optimization Toward Effective and Efficient Image Search

Author(s): Wei, SK (Wei, Shikui); Xu, D (Xu, Dong); Li, XL (Li, Xuelong); Zhao, Y (Zhao, Yao)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 6  Pages: 2216-2227  DOI: 10.1109/TCYB.2013.2245890  Published: DEC 2013  

Abstract: The bag-of-words (BoW) model has been known as an effective method for large-scale image search and indexing. Recent work shows that the performance of the model can be further improved by using the embedding method. While different variants of the BoW model and embedding method have been developed, less effort has been made to discover their underlying working mechanism. In this paper, we systematically investigate the image search performance variation with respect to a few factors of the BoW model, and study how to employ the embedding method to further improve the image search performance. Subsequently, we summarize several observations based on the experiments on descriptor matching. To validate these observations in a real image search, we propose an effective and efficient image search scheme, in which the BoW model and embedding method are jointly optimized in terms of effectiveness and efficiency by following these observations. Our comprehensive experiments demonstrate that it is beneficial to employ these observations to develop an image search algorithm, and the proposed image search scheme outperforms state-of-the-art methods in both effectiveness and efficiency.

Accession Number: WOS:000327647500058

PubMed ID: 23757530

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 16 of 223

Title: 1.23 μm emission of Er-doped water-free fluorotellurite glasses

Author(s): Zhan, H (Zhan, Huan); He, JL (He, Jianli); Zhou, ZG (Zhou, Zhiguang); Zhang, AD (Zhang, Aidong); Si, JH (Si, Jinhai); Lin, AX (Lin, Aoxiang)

Source: PHYSICS AND CHEMISTRY OF GLASSES-EUROPEAN JOURNAL OF GLASS SCIENCE AND TECHNOLOGY PART B  Volume: 54  Issue: 6  Pages: 260-263  Published: DEC 2013  

Abstract: To identify more efficient materials for 1.2 mu m fibre optical amplifiers, we report on near-infrared emission centred at 1.23 mu m from Er3+-doped water-free fluorotellurite glasses with the composition 60TeO(2)-30ZnF(2)-10NaF (TZNF60, mol%). Pumped by an OPO laser system at 523 nm, emission at 1.23 mu m (Er3+:S-4(3/2)-> I-4(11/2) transition) was observed; the tau(f) at 1.23 mu m is 21.6-86.4 mu s, arising from the optimized water-free surroundings and lower phonon energy arising from the addition of a large amount of fluoride into the tellurite-based host glass. 0.5 wt% Er2O3 doped TZNF60 glass is regarded as a promising material for the development of optical amplification and laser operation at the relatively unexplored 1.2 mu m region as it has the highest quantum efficiency and the largest figure of merit among this group of Er-TZNF60 glasses.

Accession Number: WOS:000329686300004

Author Identifiers:

ISSN: 1753-3562

Record 17 of 223

Title: Learning Saliency by MRF and Differential Threshold

Author(s): Zhu, GK (Zhu, Guokang); Wang, Q (Wang, Qi); Yuan, Y (Yuan, Yuan); Yan, PK (Yan, Pingkun)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 6  Pages: 2032-2043  DOI: 10.1109/TSMCB.2013.2238927  Published: DEC 2013  

Abstract: Saliency detection has been an attractive topic in recent years. The reliable detection of saliency can help a lot of useful processing without prior knowledge about the scene, such as content-aware image compression, segmentation, etc. Although many efforts have been spent in this subject, the feature expression and model construction are far from perfect. The obtained saliency maps are therefore not satisfying enough. In order to overcome these challenges, this paper presents a new psychologic visual feature based on differential threshold and applies it in a supervised Markov-random-field framework. Experiments on two public data sets and an image retargeting application demonstrate the effectiveness, robustness, and practicability of the proposed method.

Accession Number: WOS:000327647500042

PubMed ID: 23757590

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 18 of 223

Title: Theoretical and experimental study of 37-core waveguides with large mode area

Author(s): Wang, P (Wang, Ping); Cheng, GH (Cheng, Guanghua); Yi, RM (Yi, Ruimin); Liu, X (Liu, Xin); Shang, T (Shang, Tao); Wang, ZS (Wang, Zhansheng); Guo, LX (Guo, Lixin)

Source: APPLIED OPTICS  Volume: 52  Issue: 33  Pages: 7981-7986  DOI: 10.1364/AO.52.007981  Published: NOV 20 2013  

Abstract: The evanescently coupled multicore waveguide lattice composed of 37 linear type I cores hexagonally arranged has been theoretically studied and fabricated by low-repetition-rate femtosecond laser inscription of bulk fused silica. The effects of the single core's numerical apertures (NAs) and spacing on the mode characteristics of the 37-core waveguide were calculated by the finite-element method. It was found that the mode field areas of the fundamental mode LP01 with 5 mu m spacing of different NAs were all larger than 577 mu m(2), which was confirmed by the experiments. The measured near-field mode profiles for different writing conditions and different spacing also showed that the waveguide supported both a single mode (LP01) and two modes (LP01 and LP11). The multicore waveguide, according to our study, is particularly interesting for mode converters. (C) 2013 Optical Society of America

Accession Number: WOS:000327467200016

PubMed ID: 24513748

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 19 of 223

Title: Engineering of phase matching for mid-infrared coherent anti-Stokes Raman wavelength conversion with orthogonally polarized pump and Stokes waves in silicon-on-sapphire waveguides

Author(s): Wang, ZL (Wang, Zhaolu); Liu, HJ (Liu, Hongjun); Huang, N (Huang, Nan); Sun, QB (Sun, Qibing); Li, XF (Li, Xuefeng)

Source: APPLIED OPTICS  Volume: 52  Issue: 33  Pages: 8095-8101  DOI: 10.1364/AO.52.008095  Published: NOV 20 2013  

Abstract: The conversion efficiency of mid-infrared wavelength conversion based on coherent anti-Stokes Raman scattering with TE-polarized pump and TM-polarized Stokes waves is theoretically investigated in silicon-on-sapphire (SOS) waveguides. The peak conversion efficiency of -10 dB is obtained when the linear propagation loss is 1 dB/cm at Delta k = 0; however, it is reduced to -13.6 dB when the linear propagation loss is 2 dB/cm. The phase matching for wavelength conversion with orthogonally polarized pump and Stokes waves can be realized by engineering the birefringence in SOS waveguides, because proper phase mismatch induced by birefringence together with material dispersion-induced phase mismatch can counteract the large phase mismatch induced by waveguide dispersion. Moreover, compared with the phase matching for identically polarized pump and Stokes waves, the phase matching for orthogonally polarized pump and Stokes waves can be realized in a SOS waveguide with much smaller cross section, which reduces the power requirement for optical systems. (C) 2013 Optical Society of America

Accession Number: WOS:000327467200031

PubMed ID: 24513763

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 20 of 223

Title: Flexible high-repetition-rate ultrafast fiber laser

Author(s): Mao, D (Mao, Dong); Liu, XM (Liu, Xueming); Sun, ZP (Sun, Zhipei); Lu, H (Lu, Hua); Han, DD (Han, Dongdong); Wang, GX (Wang, Guoxi); Wang, FQ (Wang, Fengqiu)

Source: SCIENTIFIC REPORTS  Volume: 3  Article Number: 3223  DOI: 10.1038/srep03223  Published: NOV 14 2013  

Abstract: High-repetition-rate pulses have widespread applications in the fields of fiber communications, frequency comb, and optical sensing. Here, we have demonstrated high-repetition-rate ultrashort pulses in an all-fiber laser by exploiting an intracavity Mach-Zehnder interferometer (MZI) as a comb filter. The repetition rate of the laser can be tuned flexibly from about 7 to 1100 GHz by controlling the optical path difference between the two arms of the MZI. The pulse duration can be reduced continuously from about 10.1 to 0.55 ps with the spectral width tunable from about 0.35 to 5.7 nm by manipulating the intracavity polarization controller. Numerical simulations well confirm the experimental observations and show that filter-driven four-wave mixing effect, induced by the MZI, is the main mechanism that governs the formation of the high-repetition-rate pulses. This all-fiber-based laser is a simple and low-cost source for various applications where high-repetition-rate pulses are necessary.

Accession Number: WOS:000327020700013

PubMed ID: 24226153

Author Identifiers:

ISSN: 2045-2322

Record 21 of 223

Title: Computational imaging technology for high-sensitivity space-image acquisition

Author(s): Sun, JQ (Sun, Jinqiu); Li, HS (Li, Haisen); Zhang, HC (Zhang, Haichao); Zhang, YN (Zhang, Yanning); Wen, DS (Wen, Desheng)

Source: CHINESE OPTICS LETTERS  Volume: 11  Issue: 11  Article Number: 111101  DOI: 10.3788/COL201311.111101  Published: NOV 10 2013  

Abstract: Acquiring deep-space images with high spatial resolution and sensitivity is important for space-debris surveillance and early warning. We propose a novel computational imaging (CI) method for high-sensitivity image acquisition in this letter. The proposed approach introduces CI into image formation. The proposed capturing process conducts minor modifications for cameras to encode more desirable information during capture, which is practical for hardware implementation. The latent image is reconstructed by formulating a recovery problem into an optimization problem, which is solved with iteratively reweighted least square technique. The experimental results clearly show the effectiveness of the proposed method.

Accession Number: WOS:000329473900012

ISSN: 1671-7694

Record 22 of 223

Title: Investigation of Bessel beam propagation in scattering media with scalar diffraction method

Author(s): Zheng, JJ (Zheng, Juanjuan); Yao, BL (Yao, Baoli); Yang, YL (Yang, Yanlong); Lei, M (Lei, Ming); Gao, P (Gao, Peng); Li, RZ (Li, Runze); Yan, SH (Yan, Shaohui); Dan, D (Dan, Dan); Ye, T (Ye, Tong)

Source: CHINESE OPTICS LETTERS  Volume: 11  Issue: 11  Article Number: 112601  DOI: 10.3788/COL201311.112601  Published: NOV 10 2013  

Abstract: Bessel beam propagation in scattering media is simulated using the angular spectrum method combined with slice-by-slice propagation model. Generating Bessel beams with a spatial light modulator, which provides a means to adjust flexibly the parameters of the Bessel beam, allows us to validate the simulation results experimentally. The study reveals that the self-reconstructing length changes oppositely with the axicon angle (i.e., the larger the axicon angle, the shorter the self-reconstructing length). The radius of the incident beam has little influence on the self-reconstruction of the Bessel beam central lobe.

Accession Number: WOS:000329473900025

Author Identifiers:

ISSN: 1671-7694

Record 23 of 223

Title: Pedestrian detection in unseen scenes by dynamically updating visual words

Author(s): Cao, XB (Cao, Xianbin); Wang, L (Wang, Li); Ning, B (Ning, Bo); Yuan, Y (Yuan, Yuan); Yan, PK (Yan, Pingkun)

Source: NEUROCOMPUTING  Volume: 119  Special Issue: SI  Pages: 232-242  DOI: 10.1016/j.neucom.2013.03.036  Published: NOV 7 2013  

Abstract: Adapting trained detectors to unseen scenes is a critical problem in pedestrian detection. The performance of trained detector may drop quickly when scenes vary significantly. Retraining a detector with labeled samples from the new scenes may improve its performance. However, it is difficult to obtain enough labeled samples in real applications. In this paper, a novel bag of visual words based method is proposed to detect pedestrians in unseen scenes by dynamically updating the key words. The proposed method achieves its adaptability by using three strategies covering key word selection, detector invariance, and codebook update: (1) In order to select typical words representing pedestrians, a low dimensional model of visual words is built to describe their distribution and select key words using manifold learning. (2) Matching confidence vector (MCV), a novel visual words measurement is proposed, which aims to generate a uniform input vector for the fixed detector applied to different pedestrian codebooks. (3) When detecting pedestrians under changing road conditions, the key word set will be dynamically adjusted according to the matching frequency of each word to adapt the detector to the new scenes. By employing the above strategies, the proposed method is able to detect pedestrians in different scenes without retraining the detector. Experiments in different scenes showed that our proposed method can achieve better adaptability to various scenes and get better performance than other existing methods in unseen scenes. (C) 2013 Elsevier B.V. All rights reserved.

Accession Number: WOS:000323851800029

Author Identifiers:

ISSN: 0925-2312

eISSN: 1872-8286

Record 24 of 223

Title: Robust probabilistic tensor analysis for time-variant collaborative filtering

Author(s): Pan, J (Pan, Jing); Ma, Z (Ma, Zhao); Pang, YW (Pang, Yanwei); Yuan, Y (Yuan, Yuan)

Source: NEUROCOMPUTING  Volume: 119  Special Issue: SI  Pages: 139-143  DOI: 10.1016/j.neucom.2012.03.035  Published: NOV 7 2013  

Abstract: The input data of collaborative filtering, also known as recommendation system, are usually sparse and noisy. In addition, in many cases the data are time-variant and have obvious periodic property. In this paper, we take the two characteristics into account. To utilize the time-variant and periodic properties, we describe the data as a three-order tensor and then formulate the collaborative filtering as a problem of probabilistic tensor decomposition with a time-periodical constraint. The robustness is achieved by employing Tsallis divergence to describe the objective function and q-EM algorithm to find the optimal solution. The proposed method is demonstrated on movie recommendation. Experimental results on two Netflix and Movielens databases show the superiority of the proposed method. (C) 2012 Elsevier B.V. All rights reserved.

Accession Number: WOS:000323851800019

Author Identifiers:

ISSN: 0925-2312

Record 25 of 223

Title: Multiple frequency bands of square split resonant rings and metal wire metamaterial (vol 52, pg 6309, 2013)

Author(s): Gao, P (Gao, Peng); Zhang, CM (Zhang, Chunmin); Jia, ZW (Jia, Zongwei); Kang, YQ (Kang, Yongqiang)

Source: APPLIED OPTICS  Volume: 52  Issue: 31  Pages: 7523-7523  DOI: 10.1364/AO.52.007523  Published: NOV 1 2013  

Accession Number: WOS:000326568000017

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 26 of 223

Title: Multiring large-mode-area delivery fiber for high power

Author(s): Li, L (Li, Lu); Zhang, AD (Zhang, Aidong); Zhan, H (Zhan, Huan); He, JL (He, Jianli); Shi, TF (Shi, Tengfei); Zhou, ZG (Zhou, Zhiguang); Xiao, XS (Xiao, Xusheng); Lin, AX (Lin, Aoxiang)

Source: APPLIED OPTICS  Volume: 52  Issue: 31  Pages: 7407-7410  DOI: 10.1364/AO.52.007407  Published: NOV 1 2013  

Abstract: The study presents a novel design of multiring delivery fiber with large mode area for high power. Using a FiberCAD method, we investigated a fiber whose core is surrounded by alternative low-and high-index rings. Based on our calculation, the effective area is 400 mu m(2) at 1.08 mu m, larger than the similar to 280 mu m2 of conventional step-index fiber (20/400). The macrobending loss at 1.08 mu m is estimated to be 1 x 10(-3) dB/m, approximately one-third that of conventional step-index fiber (20/400). The single-mode operation can be achieved by the macrobending loss contrast between the fundamental mode (<1 dB/m) and high-order mode (>100 dB/m). The results indicate that multiring delivery fiber fabricated by modified chemical vapor deposition process is a promising candidate for high-power transmission. (C) 2013 Optical Society of America

Accession Number: WOS:000326568000002

PubMed ID: 24216638

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 27 of 223

Title: Monomode optical planar and channel waveguides in Yb<SUP>3+</SUP>-doped silicate glasses formed by helium ion implantation

Author(s): Liu, CX (Liu, Chun-Xiao); Cheng, S (Cheng, Shu); Zhao, JH (Zhao, Jin-Hua); Li, WN (Li, Wei-Nan); Wei, W (Wei, Wei); Peng, B (Peng, Bo); Guo, HT (Guo, Hai-Tao)

Source: OPTICS AND LASER TECHNOLOGY  Volume: 52  Pages: 10-14  DOI: 10.1016/j.optlastec.2013.03.017  Published: NOV 2013  

Abstract: Optical planar and channel waveguides in Yb3+-doped silicate glasses are fabricated by triple-energy helium ion implantation at a total dose of 6.0 x 10(16) ions/cm(2). The dark mode spectroscopy of the planar waveguide was measured using a prism coupling arrangement The near-field mode profiles of the planar and channel waveguide were obtained with an end-face coupling system. The refractive index profile was reconstructed by the intensity calculation method. The results indicate that a refractive index enhanced region as well as an optical barrier has been created after the beam process. After post-implantation treatment at 260 degrees C for 1 h, the channel waveguides possessed a propagation loss of similar to 1.2 dB/cm. The acceptable guiding properties suggest that further waveguide lasers may be realized on the He-implanted Yb3+-doped silicate glass waveguides. (C) 2013 Elsevier Ltd. All rights reserved.

Accession Number: WOS:000320493300002

ISSN: 0030-3992

eISSN: 1879-2545

Record 28 of 223

Title: Visible and near-infrared optical properties of chalcogenide glass waveguides formed by swift Kr ion irradiation

Author(s): Liu, T (Liu, Tao); Liu, CX (Liu, Chun-Xiao); Guo, HT (Guo, Hai-Tao); Huang, Q (Huang, Qing); Liu, P (Liu, Peng); Guo, SS (Guo, Sha-Sha); Zhang, L (Zhang, Lian); Zhou, YF (Zhou, Yu-Fan); Sun, JR (Sun, Jian-Rong); Wang, ZG (Wang, Zhi-Guang); Wang, XL (Wang, Xue-Lin)

Source: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS  Volume: 314  Pages: 166-169  DOI: 10.1016/j.nimb.2013.04.066  Published: NOV 1 2013  

Abstract: Planar waveguide structures in chalcogenide glass were fabricated with 17 MeV or 150 MeV swift Kr ion irradiation. Images of the polished end faces of the Kr-irradiated chalcogenide glass were measured with a metallographic microscope using reflected polarized light. SRIM 2010 was used to simulate the electronic and nuclear stopping powers for swift Kr ion irradiation. The micro-Raman spectra were measured in air. The near-field intensity distributions were investigated at visible (633 nm) and near-infrared (1300 nm, 1500 nm, 1539 nm and 1620 nm) bands. These intensity distributions make the waveguide candidates for infrared laser devices. The estimated propagation loss of the waveguide fabricated by 150 MeV swift Kr ion irradiation was approximately 4 dB/cm at a wavelength of 633 nm. (C) 2013 Elsevier B.V. All rights reserved.

Accession Number: WOS:000326553600038

Author Identifiers:

ISSN: 0168-583X

eISSN: 1872-9584

Record 29 of 223

Title: Synthesis and photovoltaic properties of an alternating polymer based fluorene and fluorine substituted quinoxaline derivatives

Author(s): Wu, HM (Wu, Haimei); Qu, B (Qu, Bo); Tian, D (Tian, Di); Cong, ZY (Cong, Zhiyuan); Gao, BW (Gao, Bowen); Liu, JQ (Liu, Jianqun); An, ZW (An, Zhongwei); Gao, C (Gao, Chao); Xiao, LX (Xiao, Lixin); Chen, ZJ (Chen, Zhijian); Gong, QH (Gong, Qihuang); Wei, W (Wei, Wei)

Source: REACTIVE & FUNCTIONAL POLYMERS  Volume: 73  Issue: 11  Pages: 1432-1438  DOI: 10.1016/j.reactfunctpolym.2013.07.015  Published: NOV 2013  

Abstract: An alternating polymer (PFOFTQx) with 9,9-dioctylfluorene (FO) as electron-rich unit and fluorine substituted quinoxaline (FTQx) as electron-withdrawing unit was synthesized and characterized. PFOFTQx showed similar absorption property with that of the counterpart polymer without fluorine atom (synthesized APFO-15). However, the low-lying highest occupied molecular orbit (HOMO) energy level of PFOFTQx was -5.37 eV, about 0.07 eV smaller than that of synthesized APFO-15. In order to study the photovoltaic properties of the materials, polymer solar cells (PSCs) were fabricated with PFOFTQx as donor blended with [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) as acceptor. The power conversion efficiency (PCE) of PSC was 1.77% with a high open-circuit voltage (V-oc) of 0.90 V for an optimized PFOFTQx:PC61BM weight ratio of 1:5, in comparison with that of synthesized APFO-15-based device (PCE of 1.60% with V-oc of 0.77 V). This study indicated that fluorine substituted quinoxaline-based polymers would be promising material with a higher V-oc for the application in polymer solar cells. (C) 2013 Elsevier Ltd. All rights reserved.

Accession Number: WOS:000326431800005

Author Identifiers:

ISSN: 1381-5148

eISSN: 1873-166X

Record 30 of 223

Title: Pyramid-like spikes in a single crystal superalloy produced by picosecond laser irradiation

Author(s): Zhang, W (Zhang, Wei); Cui, XZ (Cui, Xiangzhong); Feng, Q (Feng, Qiang); Cheng, GH (Cheng, Guanghua); Ma, GJ (Ma, Guojia); Zhang, XB (Zhang, Xiaobing)

Source: APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING  Volume: 113  Issue: 2  Pages: 373-377  DOI: 10.1007/s00339-013-7968-9  Published: NOV 2013  

Abstract: Pyramid-like spikes in a single crystal superalloy were investigated upon irradiation with picosecond (ps) laser pulses (200 ps, 800 nm, 1 kHz) under different laser fluences and pulse numbers. Both sides and grooves of pyramid-like spikes were covered with ripples, which had a period of similar to 760 nm. The pyramid-like spike separation increased obviously with increasing laser fluence. Microstructural investigations indicate that the pyramid-like spikes were initiated with subsequent pulses from a smooth surface with corrugations and ripples. The coexistence of capillary waves for spikes and capillary waves for ripples in the melted material can be used to explain the formation of the pyramid-like spikes.

Accession Number: WOS:000325115900019

ISSN: 0947-8396

eISSN: 1432-0630

Record 31 of 223

Title: Embedded optical waveguides fabricated in SF10 glass by low-repetition-rate ultrafast laser

Author(s): Bai, J (Bai, Jing); Long, XW (Long, Xuewen); Liu, X (Liu, Xin); Huo, GW (Huo, Guangwen); Zhao, W (Zhao, Wei); Stoian, R (Stoian, Razvan); Hui, RQ (Hui, Rongqing); Cheng, GH (Cheng, Guanghua)

Source: APPLIED OPTICS  Volume: 52  Issue: 30  Pages: 7288-7294  DOI: 10.1364/AO.52.007288  Published: OCT 20 2013  

Abstract: Symmetric embedded waveguides were fabricated in heavy metal oxide SF10 glass using slit-shaped infrared femtosecond laser writing in the low-repetition frequency regime. The impact of the writing parameters on the waveguide formation in the transverse writing scheme was systemically studied. Results indicate that efficient waveguides can be inscribed in a wide parameter space ranging from 500 fs to 1.5 ps pulse duration, 0.7-4.2 mu J pulse energy, and 5 mu m/s to 640 mu m/s scan speed and pointing out the robustness of the photoinscription process. The refractive index profile reconstructed from the measured near field pattern goes up to 10(-3). In addition, propagation losses of the waveguides are tolerable, with the lowest propagation loss estimated at 0.7 dB/cm. With a 5 mu m/s scan speed and 3.5 mu J pulse energy in a high-dose regime, few-mode guiding was achieved in the waveguide at 800 nm signal injection wavelength. This is due to a combination of increased refractive index in the core of the trace and the appearance of a depressed cladding. (C) 2013 Optical Society of America

Accession Number: WOS:000325926600009

PubMed ID: 24216582

Author Identifiers:

ISSN: 1559-128X

eISSN: 2155-3165

Record 32 of 223

Title: Watt-level passively <i>Q</i>-switched double-cladding fiber laser based on graphene oxide saturable absorber

Author(s): Yu, ZH (Yu, Zhenhua); Song, YR (Song, Yanrong); Dong, XZ (Dong, Xinzheng); Li, YL (Li, Yanlin); Tian, JR (Tian, Jinrong); Wang, YG (Wang, Yonggang)

Source: APPLIED OPTICS  Volume: 52  Issue: 29  Pages: 7127-7131  DOI: 10.1364/AO.52.007127  Published: OCT 10 2013  

Abstract: A watt-level passively Q-switched ytterbium-doped double-cladding fiber laser with a graphene oxide (GO) absorber was demonstrated. The structure of the GO saturable absorber mirror (GO-SAM) was of the sandwich type. A maximum output power of 1.8 W was obtained around a wavelength of 1044 nm. To the best of our knowledge, this is the highest output power in Q-switched fiber lasers based on a GO saturable absorber. The pure GO was protected from the oxygen in the air so that the damage threshold of the GO-SAM was effectively raised. The gain fiber was a D-shaped ytterbium-doped double-cladding fiber. The pulse repetition rates were tuned from 120 to 215 kHz with pump powers from 3.89 to 7.8 W. The maximum pulse energy was 8.37 mu J at a pulse width of 1.7 mu s. (c) 2013 Optical Society of America

Accession Number: WOS:000325764900010

PubMed ID: 24217729

ISSN: 1559-128X

eISSN: 2155-3165

Record 33 of 223

Title: Low repetition rate subnanosecond pulse laser generation from a diode pumped Nd:Lu₃Al₅O₁₂ laser with electro-optic modulator and transmission semiconductor saturable absorber

Author(s): Chang, L (Chang, L.); Zhao, SZ (Zhao, S. Z.); Yang, KJ (Yang, K. J.); Zhao, J (Zhao, J.); Zheng, LH (Zheng, L. H.); Xu, XD (Xu, X. D.); Di, JQ (Di, J. Q.); Xu, J (Xu, J.); Wang, YG (Wang, Y. G.)

Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS  Volume: 30  Issue: 10  Pages: 2710-2714  DOI: 10.1364/JOSAB.30.002710  Published: OCT 2013  

Abstract: By using the dual-loss modulated technology, i.e., adopting the electro-optic (EO) modulator and transmission semiconductor saturable absorber (transmission SSA) simultaneously, a diode-pumped doubly Q-switched and mode-locked (QML) Nd:Lu3Al5O12 (Nd: LuAG) laser at 1.06 mu m has been realized for the first time. In comparison to the singly passively QML Nd: LuAG laser with transmission SSA, the doubly QML laser can generate more stable pulses with shorter pulse widths and higher peak powers. It can also be observed that the pulse duration of the Q-switched envelope decreases with increasing pump power. When the pump power exceeds 6.52 W for the first time, there is only one mode-locked pulse underneath a Q-switched envelope for this doubly QML Nd: LuAG laser. As a result, the subnanosecond pulse laser with 1 kHz repetition rate of EO and high stability can be generated. The shortest pulse duration generated is about 718 ps and the highest peak power reaches as high as 502 kW. The experimental results show that Nd: LuAG is an excellent alternative crystal for diode-pumped QML pulsed laser generation. (C) 2013 Optical Society of America

Accession Number: WOS:000325215500020

Author Identifiers:

ISSN: 0740-3224

eISSN: 1520-8540

Record 34 of 223

Title: Spectroscopic and laser-induced damage properties of Fe<SUP>2+</SUP>-doped fluorophosphate glass, a new color-separation material

Author(s): Fu, LL (Fu, Lili); Ren, WY (Ren, Wenyi); Liu, CX (Liu, Chunxiao); Xu, SN (Xu, Shennuo); Zheng, RL (Zheng, Ruilin); Wei, W (Wei, Wei); Zhang, CM (Zhang, Chunmin); Peng, B (Peng, Bo)

Source: APPLIED PHYSICS B-LASERS AND OPTICS  Volume: 113  Issue: 1  Pages: 81-86  DOI: 10.1007/s00340-013-5652-6  Published: OCT 2013  

Abstract: Fe2+-doped fluorophosphate glass (FEFG), a new color-separation material, is prepared by a melt-quenching method. The spectroscopic and laser-induced damage (LID) properties of FEFG are investigated by transmittance spectroscopy, LID tests, scanning electron microscopy, and Raman spectroscopy. Results show that the sample has intensive absorption (> 85 %) at 1,053 nm and high transmittance (similar to 86.5 %) at 351 nm after introducing 0.3 wt% Fe2O3. The LID thresholds of 0.3 wt% Fe2O3-doped FEFG sample irradiated by 351- and 1,053-nm lasers with 8 ns pulse width are 4.5 and 36.0 J/cm(2), respectively. Thus, FEFG has laser-separation ability and can resist nanosecond laser irradiation, indicating that FEFG is a potential color-separation material for high-power lasers.

Accession Number: WOS:000326598200010

Author Identifiers:

ISSN: 0946-2171

eISSN: 1432-0649

Record 35 of 223

Title: Spectroscopic properties and Judd-Ofelt analysis of Dy<SUP>3+</SUP>-doped and Dy<SUP>3+</SUP>, Tm<SUP>3+</SUP>-codped Ge-In-S chalcogenide glasses

Author(s): Guo, HT (Guo, Haitao); Xu, YT (Xu, Yantao); Chen, HY (Chen, Hongyan); Cui, XX (Cui, Xiaoxia); Qiao, ZB (Qiao, Zebang); Gu, SX (Gu, Shaoxuan); Hou, CQ (Hou, Chaoqi); Meng, W (Meng, Wei); Lu, CF (Lu, Chunfeng); Peng, B (Peng, Bo)

Source: JOURNAL OF NON-CRYSTALLINE SOLIDS  Volume: 377  Special Issue: SI  Pages: 95-99  DOI: 10.1016/j.jnoncrysol.2013.01.013  Published: OCT 1 2013  

Abstract: 0.2 wt.% Dy3+-doped and 0.2 wt.% Dy3+, 0.5 wt.% Tm3+-codoped (100-x)GeS2 center dot xIn(2)S(3) (x = 5,10,15,20,25) chalcogenide glasses were prepared. Their spectroscopic properties were analyzed based on absorption (ranges from 500 to 3000 nm) and emission (ranges from 1000 to 4700 nm) measurements. The Judd-Ofelt strength parameters Omega(t) (t = 2, 4, 6) and the spectroscopy parameters A(rad), beta and T-rad were calculated, and the sigma(emi) of the 1330, 2930 and 4320 nm fluorescences were estimated. These Dy3+-doped and Dy3+, Tm3+-codoped Ge-In-S chalcogenide glasses are valuable materials for using in 1.3 mu m fiber-amplifiers and 2-5 mu m mid-infrared laser devices. (C) 2013 Elsevier B.V. All rights reserved.

Accession Number: WOS:000325304800022

Conference Title: 18th International Symposium on Non-Oxide and New Optical Glasses

Conference Date: JUL 01-05, 2012

Conference Location: Saint Malo, FRANCE

Conference Sponsors: Inst Chem Sci Rennes, Univ Rennes 1, Conseil Gen Ille & Vilaine, CNRS GDR Verres, AdValue Photon, Bretagne Photon, Mettler Toledo, PerkinElmer Inc, Off Naval Res

ISSN: 0022-3093

eISSN: 1873-4812

Record 36 of 223

Title: Study on 2.0 μm fluorescence of Ho-doped water-free fluorotellurite glasses

Author(s): He, JL (He, Jianli); Zhan, H (Zhan, Huan); Zhou, ZG (Zhou, Zhiguang); Zhang, AD (Zhang, Aidong); Lin, AX (Lin, Aoxiang)

Source: OPTICAL MATERIALS  Volume: 35  Issue: 12  Pages: 2573-2576  DOI: 10.1016/j.optmat.2013.07.031  Published: OCT 2013  

Abstract: Ho(3+-)doped water-free fluorotellurite glasses with composition of 60TeO(2)-30ZnF(2)-10NaF (mol%, TZNF60) were made by using specially-designed physical and chemical dehydration technique. 2.04 mu m fluorescence (Ho3+: I-5(7) -> I-5(8)) was observed experimentally and presented in this paper: A broad bandwidth of similar to 149 nm, large simulated emission cross-section of 7.2 x 10(-21) cm(2), and the longest reported fluorescence lifetime of similar to 10 ms among all the reported Ho3+-doped oxide glasses. Thanks to the absence of OH groups and low phonon energy with the addition fluorides into tellurite oxide glasses, 1.00Ho-TZNF60 glass demonstrates the maximum figure of merit (sigma(em) x tau(f)) of 7.13 x 10(-27) m(2) s, thus regarded as a promising optical material for the development of 2.0 mu m fiber lasers. (C) 2013 Elsevier B.V. All rights reserved.

Accession Number: WOS:000326660500091

ISSN: 0925-3467

eISSN: 1873-1252

Record 37 of 223

Title: Visual saliency detection using information divergence

Author(s): Hou, WL (Hou, Weilong); Gao, XB (Gao, Xinbo); Tao, DC (Tao, Dacheng); Li, XL (Li, Xuelong)

Source: PATTERN RECOGNITION  Volume: 46  Issue: 10  Pages: 2658-2669  DOI: 10.1016/j.patcog.2013.03.008  Published: OCT 2013  

Abstract: The technique of visual saliency detection supports video surveillance systems by reducing redundant information and highlighting the critical, visually important regions. It follows that information about the image might be of great importance in depicting the visual saliency. However, the majority of existing methods extract contrast-like features without considering the contribution of information content. Based on the hypothesis that information divergence leads to visual saliency, a two-stage framework for saliency detection, namely information divergence model (IDM), is introduced in this paper. The term "information divergence" is used to express the non-uniform distribution of the visual information in an image. The first stage is constructed to extract sparse features by employing independent component analysis (ICA) and difference of Gaussians (DOG) filter. The second stage improves the Bayesian surprise model to compute information divergence across an image. A visual saliency map is finally obtained from the information divergence. Experiments are conducted on nature image databases, psychological patterns and video surveillance sequences. The results show the effectiveness of the proposed method by comparing it with 13 state-of-the-art visual saliency detection methods. (C) 2013 Elsevier Ltd. All rights reserved.

Accession Number: WOS:000320477400005

Author Identifiers:

ISSN: 0031-3203

eISSN: 1873-5142

Record 38 of 223

Title: Double-cutting beam shaping technique for high-power diode laser area light source

Author(s): Huang, ZH (Huang, Zhihua); Xiong, LL (Xiong, Lingling); Liu, H (Liu, Hui); Wang, ZF (Wang, Zhenfu); Zhang, P (Zhang, Pu); Nie, ZQ (Nie, Zhiqiang); Wu, DH (Wu, Dihai); Liu, XS (Liu, Xingsheng)

Source: OPTICAL ENGINEERING  Volume: 52  Issue: 10  Article Number: 106108  DOI: 10.1117/1.OE.52.10.106108  Published: OCT 2013  

Abstract: A new beam-shaping technique is proposed to improve the beam quality of a high-power diode laser area light source. It consists of two staggered prism arrays and a reflector array, which can cut the slow axis beam twice and rearrange the divided beams in fast axis to make the beam quality of both axes approximately equal. Furthermore, the beam transformation and compression can be carried out simultaneously, and the assembly error of this technique induced by the machining accuracy of prism's dimensions also can be greatly decreased. By this technique, a fiber-coupled system for one three-bar laser diode stack is designed and characterized. The experimental results demonstrate that the laser beams could be transformed into the required distribution with similar to 93.4% reshaped efficiency and coupled into a 400 mu m/0.22 NA fiber, which are consistent with the theory. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)

Accession Number: WOS:000328254600064

ISSN: 0091-3286

eISSN: 1560-2303

Record 39 of 223

Title: Wide-Range Continuously-Tunable Slow-Light Delay Line Based on Stimulated Brillouin Scattering

Author(s): Ju, HJ (Ju, Haijuan); Ren, LY (Ren, Liyong); Lin, X (Lin, Xiao); Liang, J (Liang, Jian); Ma, CJ (Ma, Chengju)

Source: IEEE PHOTONICS TECHNOLOGY LETTERS  Volume: 25  Issue: 19  Pages: 1920-1923  DOI: 10.1109/LPT.2013.2278536  Published: OCT 1 2013  

Abstract: Through selectively controlling the stimulated Brillouin scattering in optical fibers with different lengths, a continuously tunable time-delay scheme enabling to work in a large range is proposed in this letter. This is realized by connecting a fixed long single-mode fiber (SMF) to one of the several selectable short SMFs that successively have an equal increment in length. These short-length fibers are, respectively, fixed to the different channels between two identical optical switches. Therefore, a wide-range and continuously tunable slow-light delay line can be constructed by changing the power of the pump beam, assisted by switching to different channels. In the experiment, a time delay from 0 to 201.29 ns is demonstrated for a five-channel configuration. A further large-range time delay can be expected if one adds the number of channels accordingly.

Accession Number: WOS:000324766700005

Author Identifiers:

ISSN: 1041-1135

eISSN: 1941-0174

Record 40 of 223

Title: Passive <i>Q</i>-switched mode locking of a diode-pumped Tm:SSO laser near 2 μm

Author(s): Liu, J (Liu, J.); Li, YQ (Li, Y. Q.); Zheng, LH (Zheng, L. H.); Su, LB (Su, L. B.); Xu, J (Xu, J.); Wang, YG (Wang, Y. G.)

Source: LASER PHYSICS LETTERS  Volume: 10  Issue: 10  Article Number: 105812  DOI: 10.1088/1612-2011/10/10/105812  Published: OCT 2013  

Abstract: With a fiber-coupled 790 nm laser diode array as the pump source and a 4 at.% Tm:Sc2SiO5 (Tm:SSO) crystal, laser action near 2 mu m wavelength was successfully obtained with a compact four-mirror fold cavity. Using broadband carbon nanotube as the saturable absorber, a passively Q-switched mode-locked (QML) Tm: SSO laser is realized for the first time. 100% modulation depth of mode locking has been achieved. The duration of the mode-locked pulse is estimated to be about sub-100 ps with 92.6 MHz repetition rate within a Q-switched pulse envelope. The spectrum of the QML laser is centered at 1967.4 nm with a broad spectral region of similar to 23 nm. A maximum average output power of 195 mW and Q-switched pulse energy of 4.7 mu J is obtained. The dependence of the operational parameters on pump power was also investigated experimentally.

Accession Number: WOS:000327158700032

ISSN: 1612-2011

eISSN: 1612-202X

Record 41 of 223

Title: Characteristics of a diode-pumped Yb:CaF₂-SrF₂ mode-locked laser using a carbon nanotube absorber

Author(s): Liu, J (Liu, J.); Feng, C (Feng, C.); Su, LB (Su, L. B.); Jiang, DP (Jiang, D. P.); Zheng, LH (Zheng, L. H.); Qian, XB (Qian, X. B.); Wang, JY (Wang, J. Y.); Xu, J (Xu, J.); Wang, YG (Wang, Y. G.)

Source: LASER PHYSICS LETTERS  Volume: 10  Issue: 10  Article Number: 105806  DOI: 10.1088/1612-2011/10/10/105806  Published: OCT 2013  

Abstract: Yb:CaF2-SrF2 disordered crystals are successfully grown by the TGT method. By using a double-walled carbon nanotube saturable absorber (DWCNT-SA), the continuous-wave mode-locked (CWML) laser properties of Yb:CaF2-SrF2 crystals are demonstrated under diode pumping for the first time. The mode-locked laser delivers pulses as short as 5 ps at a center wavelength of 1045.5 nm without any dispersion compensation. The oscillator operating at a repetition rate of similar to 87 MHz delivers 292 mW average output power.

Accession Number: WOS:000327158700026

ISSN: 1612-2011

eISSN: 1612-202X

Record 42 of 223

Title: Buried waveguide in neodymium-doped phosphate glass obtained by femtosecond laser writing using a double line approach

Author(s): Long, XW (Long, Xuewen); Bai, J (Bai, Jing); Liu, X (Liu, Xin); Zhao, W (Zhao, Wei); Cheng, GH (Cheng, Guanghua)

Source: CHINESE OPTICS LETTERS  Volume: 11  Issue: 10  Article Number: 102301  DOI: 10.3788/COL201311.102301  Published: OCT 1 2013  

Abstract: We fabricate a buried channel waveguide in neodymium-doped phosphate glass using a double line approach by femtosecond laser writing. Raman spectra reveal an expansion of the glass network in the laser irradiated region. Given the stress-induced positive refractive index change, waveguiding between two separated tracks is demonstrated. The refractive index difference profile of the waveguide is reconstructed from the measured near-field mode. Propagation loss is measured by scattering technique. Micro luminescence spectra reveal that the Nd3+ fluorescence property is not significantly affected by waveguide formation process, which indicates that the inscribed waveguide is a good candidate for active device.

Accession Number: WOS:000327321800018

Author Identifiers:

ISSN: 1671-7694

Record 43 of 223

Title: Manipulation of light in MIM plasmonic waveguide systems

Author(s): Lu, H (Lu Hua); Wang, GX (Wang GuoXi); Liu, XM (Liu XueMing)

Source: CHINESE SCIENCE BULLETIN  Volume: 58  Issue: 30  Pages: 3607-3616  DOI: 10.1007/s11434-013-5989-6  Published: OCT 2013  

Abstract: Plasmonic waveguides that allow deeply subwavelength confinement of light provide an effective platform for the design of ultra-compact photonic devices. As an important plasmonic waveguide, metal-insulator-metal (MIM) structure supports the propagation of light in the nanoscale regime at the visible and near-infrared ranges. Here, we focus on our work in MIM plasmonic waveguide devices for manipulating light, and review some of the recent development of this topic. We introduce MIM plasmonic wavelength filtering and demultiplexing devices, and present the electromagnetic induced transparency (EIT)-like and Fano resonance effects in MIM waveguide systems. The slow-light and rainbow trapping effects are demonstrated theoretically. These results pave a way toward dynamic control of the special and useful optical responses, which actualize some new plasmonic waveguide-integrated devices such as nanoscale filters, demultiplexers, sensors, slow light waveguides, and buffers.

Accession Number: WOS:000325126500003

Author Identifiers:

ISSN: 1001-6538

eISSN: 1861-9541

Record 44 of 223

Title: Depth-Aware Image Seam Carving

Author(s): Shen, JB (Shen, Jianbing); Wang, DP (Wang, Dapeng); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 5  Special Issue: SI  Pages: 1453-1461  DOI: 10.1109/TCYB.2013.2273270  Published: OCT 2013  

Abstract: Image seam carving algorithm should preserve important and salient objects as much as possible when changing the image size, while not removing the secondary objects in the scene. However, it is still difficult to determine the important and salient objects that avoid the distortion of these objects after resizing the input image. In this paper, we develop a novel depth-aware single image seam carving approach by taking advantage of the modern depth cameras such as the Kinect sensor, which captures the RGB color image and its corresponding depth map simultaneously. By considering both the depth information and the just noticeable difference (JND) model, we develop an efficient JND-based significant computation approach using the multiscale graph cut based energy optimization. Our method achieves the better seam carving performance by cutting the near objects less seams while removing distant objects more seams. To the best of our knowledge, our algorithm is the first work to use the true depth map captured by Kinect depth camera for single image seam carving. The experimental results demonstrate that the proposed approach produces better seam carving results than previous content-aware seam carving methods.

Accession Number: WOS:000324586700013

PubMed ID: 23893762

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 45 of 223

Title: Investigation and control of ultrafast laser-induced isotropic and anisotropic nanoscale-modulated index patterns in bulk fused silica

Author(s): Stoian, R (Stoian, R.); Mishchik, K (Mishchik, K.); Cheng, G (Cheng, G.); Mauclair, C (Mauclair, C.); D'Amico, C (D'Amico, C.); Colombier, JP (Colombier, J. P.); Zamfirescu, M (Zamfirescu, M.)

Source: OPTICAL MATERIALS EXPRESS  Volume: 3  Issue: 10  Pages: 1755-1768  DOI: 10.1364/OME.3.001755  Published: OCT 1 2013  

Abstract: Ultrafast laser-induced refractive index changes in a-SiO2 consist, depending on the irradiation conditions, of either positive variations, voids, or regular nanoscale patterns, each of these underlying specific structural transformations. These allow for obtaining a large palette of optical functions ranging from low loss guiding to anisotropic scattering. While briefly reviewing the excitation mechanisms, we spectroscopically interrogate local electronic and structural transformations of the glass in the isotropic index zones and in the regular self-organized nanostructures, indicating bond breaking and matrix oxygen deficiency. A spatial defect segregation marks the material transformation in the different photoinscription regimes. We equally propose a method of real time control of nanogratings formation under the action of ultrashort laser pulse with variable envelopes. Application as polarizing optical devices is discussed. (C) 2013 Optical Society of America

Accession Number: WOS:000325206300020

Author Identifiers:

ISSN: 2159-3930

Record 46 of 223

Title: Person Re-Identification by Regularized Smoothing KISS Metric Learning

Author(s): Tao, DP (Tao, Dapeng); Jin, LW (Jin, Lianwen); Wang, YF (Wang, Yongfei); Yuan, Y (Yuan, Yuan); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY  Volume: 23  Issue: 10  Pages: 1675-1685  DOI: 10.1109/TCSVT.2013.2255413  Published: OCT 2013  

Abstract: With the rapid development of the intelligent video surveillance (IVS), person re-identification, which is a difficult yet unavoidable problem in video surveillance, has received increasing attention in recent years. That is because computer capacity has shown remarkable progress and the task of person re-identification plays a critical role in video surveillance systems. In short, person re-identification aims to find an individual again that has been observed over different cameras. It has been reported that KISS metric learning has obtained the state of the art performance for person re-identification on the VIPeR dataset [39]. However, given a small size training set, the estimation to the inverse of a covariance matrix is not stable and thus the resulting performance can be poor. In this paper, we present regularized smoothing KISS metric learning (RS-KISS) by seamlessly integrating smoothing and regularization techniques for robustly estimating covariance matrices. RS-KISS is superior to KISS, because RS-KISS can enlarge the underestimated small eigenvalues and can reduce the overestimated large eigenvalues of the estimated covariance matrix in an effective way. By providing additional data, we can obtain a more robust model by RS-KISS. However, retraining RS-KISS on all the available examples in a straightforward way is time consuming, so we introduce incremental learning to RS-KISS. We thoroughly conduct experiments on the VIPeR dataset and verify that 1) RS-KISS completely beats all available results for person re-identification and 2) incremental RS-KISS performs as well as RS-KISS but reduces the computational cost significantly.

Accession Number: WOS:000325662200004

Author Identifiers:

ISSN: 1051-8215

eISSN: 1558-2205

Record 47 of 223

Title: Rank Preserving Sparse Learning for Kinect Based Scene Classification

Author(s): Tao, DP (Tao, Dapeng); Jin, LW (Jin, Lianwen); Yang, Z (Yang, Zhao); Li, XL (Li, Xuelong)

Source: IEEE TRANSACTIONS ON CYBERNETICS  Volume: 43  Issue: 5  Special Issue: SI  Pages: 1406-1417  DOI: 10.1109/TCYB.2013.2264285  Published: OCT 2013  

Abstract: With the rapid development of the RGB-D sensors and the promptly growing population of the low-cost Microsoft Kinect sensor, scene classification, which is a hard, yet important, problem in computer vision, has gained a resurgence of interest recently. That is because the depth of information provided by the Kinect sensor opens an effective and innovative way for scene classification. In this paper, we propose a new scheme for scene classification, which applies locality-constrained linear coding (LLC) to local SIFT features for representing the RGB-D samples and classifies scenes through the cooperation between a new rank preserving sparse learning (RPSL) based dimension reduction and a simple classification method. RPSL considers four aspects: 1) it preserves the rank order information of the within-class samples in a local patch; 2) it maximizes the margin between the between-class samples on the local patch; 3) the L1-norm penalty is introduced to obtain the parsimony property; and 4) it models the classification error minimization by utilizing the least-squares error minimization. Experiments are conducted on the NYU Depth V1 dataset and demonstrate the robustness and effectiveness of RPSL for scene classification.

Accession Number: WOS:000324586700009

PubMed ID: 23846511

Author Identifiers:

ISSN: 2168-2267

eISSN: 2168-2275

Record 48 of 223