2010
2010
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Record 157 of
Title:Image ratio features for facial expression recognition application
Author(s):Song, Mingli(1); Tao, Dacheng(2); Liu, Zicheng(3); Li, Xuelong(4); Zhou, Mengchu(5)Source: IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics Volume: 40 Issue: 3 DOI: 10.1109/TSMCB.2009.2029076 Published: June 2010Abstract:Video-based facial expression recognition is a challenging problem in computer vision and humancomputer interaction. To target this problem, texture features have been extracted and widely used, because they can capture image intensity changes raised by skin deformation. However, existing texture features encounter problems with albedo and lighting variations. To solve both problems, we propose a new texture feature called image ratio features. Compared with previously proposed texture features, e.g., high gradient component features, image ratio features are more robust to albedo and lighting variations. In addition, to further improve facial expression recognition accuracy based on image ratio features, we combine image ratio features with facial animation parameters (FAPs), which describe the geometric motions of facial feature points. The performance evaluation is based on the Carnegie Mellon University CohnKanade database, our own database, and the Japanese Female Facial Expression database. Experimental results show that the proposed image ratio feature is more robust to albedo and lighting variations, and the combination of image ratio features and FAPs outperforms each feature alone. In addition, we study asymmetric facial expressions based on our own facial expression database and demonstrate the superior performance of our combined expression recognition system. ? 2006 IEEE.Accession Number: 20102112951942 -
Record 158 of
Title:Faraday glasses with a large size and high performance
Author(s):Li, Weinan(1); Zou, Kuaisheng(1); Lu, Min(1); Peng, Bo(1); Zhao, Wei(1)Source: International Journal of Applied Ceramic Technology Volume: 7 Issue: 3 DOI: 10.1111/j.1744-7402.2008.02344.x Published: May-June 2010Abstract:A kind of Faraday glass with a size of Φ40 mm × 14 mm and Φ100-300 mm × 25 mm, respectively, was prepared by the melting and casting process, which had neither a Pt particulate nor a bubble or striation. The measurement results showed that the surface homogeneity of the samples was up to ± 1 × 10-6, the laser threshold reached 10 J/cm2 (1ω, 3 ns), and the Verdet constants of the glasses were -0.273 min/Oe/cm at 632.8 nm and -0.076 min/Oe/cm at 1064 nm, respectively. ? 2009 The American Ceramic Society.Accession Number: 20101912916463 -
Record 159 of
Title:Spatially modulated fourier transform imaging spectrometer data compression research
Author(s):Huang, Min(1,2); Xiangli, Bin(1,3); Yuan, Yan(4); Shen, Zhong(5); Lü, Qun-Bo(1,2); Wang, Zhong-Hou(1); Liu, Xue-Bin(1)Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis Volume: 30 Issue: 1 DOI: 10.3964/j.issn.1000-0593(2010)01-0278-05 Published: January 2010Abstract:Fourier transform imaging spectrometer is a new technic, and has been developed very fast in recent ten years. When it is used in satellite, because of the limit by the data transmission, the authors need to compress the original data obtained by the Fourier transform imaging spectrometer, then, the data can be transmitted, and can be incepted on the earth and decompressed. Then the authors can do data process to get spectrum data which can be used by user. Data compression technic used in Fourier transform imaging spectrometer is a new technic, and few papers introduce it at home and abroad. In this paper the authors will give a data compression method, which has been used in EDIS, and achieved a good result.Accession Number: 20100312640970 -
Record 160 of
Title:Linear and nonlinear optical properties of the PbSe quantum dots doped germano-silica glass optical fiber
Author(s):Watekar, Pramod R.(1,2); Ju, Seongmin(2); Lin, Aoxiang(3,4); Kim, Myoung Jin(1); Lee, Byeong Ha(1); Han, Won-Taek(1,2)Source: Journal of Non-Crystalline Solids Volume: 356 Issue: 44-49 DOI: 10.1016/j.jnoncrysol.2010.02.012 Published: October 1, 2010Abstract:We report development of a new fiber doped with PbSe quantum dots for nonlinear optical applications. PbSe quantum dots related absorption peaks were obtained at 1021, 1093 and 1351 nm. The resonant optical nonlinearity and attenuation at 1500 nm were measured to be 9.4 × 10-16 m2/W and 0.01 dB/m, respectively. The emission around 1540 nm was observed upon near resonant pumping at 1064 nm. ? 2010 Elsevier B.V. All rights reserved.Accession Number: 20104713405328 -
Record 161 of
Title:One-spot and multispot processing for supermode stabilization
Author(s):Cai, Ran(1); Xue, Cai(3); Zeng, Lan(3); Chen, Jianguo(2); Cai, Guishun(3); Hu, Shijie(4); Cao, Jie(5); Rong, Jian(1); Dong, Jihui(6)Source: Applied Optics Volume: 49 Issue: 14 DOI: 10.1364/AO.49.002703 Published: May 10, 2010Abstract:Through employing an external mirror that is tilted by an angle β = λ/2d in the external cavity, whose round-trip cavity length is one-half a Talbot distance, a laser diode array (LDA) is made to oscillate with only an in-phase supermode. This makes the far-field distribution of the LDA have a central-single-lobe far-field pattern, and it also makes the output from the LDA be nearly diffraction limited. However, if the phase-locked output energy from the LDA is extremely high, then the thermal radiation from the output deforms the external mirror stochastically. This makes the tilt angle (β) mismatched to the in-phase supermode, which results in undesirable supermode oscillations; so the far-field distribution of the LDA is no longer a central-single-lobe far-field pattern. Naturally, the intensity of the output from the LDA is attenuated, and the divergence loss is worsened. Therefore, suitable measures must be taken to guarantee the quality of the phase-locked output from the LDA. Accordingly, after analysis of the deformation of the external mirror, a novel one-spot and multispot processing (OMP) technology is developed. With special sensors, deformation of the external mirror is ascertained as a function of time. Then the deformation is compensated by appropriate equipment, which counteracts any bad influence on the angle β. The experiment significantly demonstrates that only the in-phase supermode oscillated in an extremely high-energy LDA after the implementation of OMP, allowing such lasers to satisfy the requirements of high-quality laser applications. ? 2010 Optical Society of America.Accession Number: 20103513189041 -
Record 162 of
Title:Primary scientific results of Chang'E-1 lunar mission
Author(s):Ouyang, Zi Yuan(1,2); Li, ChunLai(1); Zou, YongLiao(1); Zhang, HongBo(1); Lü, Chang(1); Liu, JianZhong(1); Liu, JianJun(1); Zuo, Wei(1); Su, Yan(1); Wen, WeiBin(1); Bian, Wei(1); Zhao, BaoChang(3); Wang, JianYu(4); Yang, JianFeng(3); Chang, Jin(5); Wang, HuanYu(6); Zhang, XiaoHui(7); Wang, ShiJin(7); Wang, Min(1); Ren, Xin(1); Mu, LingLi(1); Kong, DeQing(1); Wang, XiaoQian(1); Wang, Fang(1); Geng, Liang(1); Zhang, ZhouBin(1); Zheng, Lei(1); Zhu, XinYing(1); Zheng, YongChun(1); Li, JunDuo(1); Zou, XiaoDuan(1); Xu, Chun(1); Shi, ShuoBiao(1); Gao, YiFei(1); Gao, GuanNan(1)Source: Science China Earth Sciences Volume: 53 Issue: 11 DOI: 10.1007/s11430-010-4056-2 Published: November 2010Abstract:The strategic plan for the development of the unmanned Chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first Chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first Chinese lunar exploration mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future Chinese lunar missions. ? 2010 Science China Press and Springer-Verlag Berlin Heidelberg.Accession Number: 20104713409445 -
Record 163 of
Title:Terahertz rate pulse train generation using nonlinear effects in nanoscale silicon waveguides
Author(s):Wu, Jian-Wei(1,2,3); Lee, Hyun-Shik(2); Lee, El-Hang(2)Source: 2010 International Conference on Multimedia Technology, ICMT 2010 Volume: Issue: DOI: 10.1109/ICMULT.2010.5629793 Published: 2010Abstract:We report on the new method of generating an ultra-high rate pulse train at a repetition rate of 2-THz by utilizing the combined effects of nonlinear frequency chirp and group velocity dispersion in nanoscale silicon on insulator (SOI) optical waveguides. As two optical beams modulated by the initial sinusoidal modulation elements propagate through the SOI, they are reshaped into a pulse train, in which the repetition rate can be predetermined by the modulation frequency. At the end of a 2-mm long silicon waveguide, the full width of half maximum (FWHM) of the output pulse can be compressed to about 62-fs, leading to THz pulse repetition rate. ?2010 IEEE.Accession Number: 20111013721392 -
Record 164 of
Title:Affine-invariant SIFT descriptor with global context
Author(s):Cao, Bei(1); Ma, CaiWen(1); Liu, ZhenTao(2)Source: Proceedings - 2010 3rd International Congress on Image and Signal Processing, CISP 2010 Volume: 1 Issue: DOI: 10.1109/CISP.2010.5647071 Published: 2010Abstract:The paper proposed a new image matching method combining affine-invariant SIFT feature descriptor with global context. Affine-SIFT (ASIFT) can find large numbers of correct matches even with great variation of camera axis orientation, however when there are several similar regions or objects between the query and search images, it may also produce many mismatches. Therefore, we intend to introduce global context to resolve ambiguities that can occur locally when an image has multiple similar regions. A global context vector that adds curvilinear shape information from a much larger neighborhood, thus reducing mismatches when multiple local descriptors are similar. We have tested our method on various images and compare matching accuracy between the ASIFT descriptor with global context to that without. ?2010 IEEE.Accession Number: 20105213529091 -
Record 165 of
Title:A novel and robust axis extraction method
Author(s):Cao, Bei(1); Ma, CaiWen(1); Liu, ZhenTao(2)Source: Proceedings - 2010 3rd International Congress on Image and Signal Processing, CISP 2010 Volume: 2 Issue: DOI: 10.1109/CISP.2010.5646878 Published: 2010Abstract:This paper presents a novel and robust method for accurately extracting axis equation from axis symmetry objects. Our method combines Hough transform with centroid analysis technique to output sub-pixel axis equation. It is robust even in imperfect image qualities for fully use of regional grayscale pixel values while not relying on edges of objects. The whole process requires no information other than the input grayscale images. The results illustrate that our method is capable of extracting accurate axis while achieving near real-time performance. ?2010 IEEE.Accession Number: 20105213529849 -
Record 166 of
Title:Analysis of bonding stress with high strength adhesive between the reflector and the mounts in space camera
Author(s):Li, Yan(1); Hu, YongMing(1); Li, YingCai(1); Qu, YouShan(1); Ding, JiaoTeng(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 7654 Issue: DOI: 10.1117/12.867760 Published: 2010Abstract:The bond stress is analyzed when the optics were attached to their mounts with high strength adhesive in space camera. The model was founded that a circular planar reflector supported by one, three, six or twelve adhesive points, which evenly distributed on different circles. The surface deformation of reflector is mainly caused by the shrinkage after solidity. The functional relation was deduced between the bonding force of the reflector and the characteristic dimension of the adhesive spot using piecewise function, and then analyzing the RMS error of no gravity assuming that the adhesive spot is fixed connect to the reflector using Nastran. The analytical RMS error was the aberration which added by solidification of adhesive. The calculation result is in good agreement with the experiment results. This analyzing method will be useful for the microstress clamping of high performance reflector system for application in space optical systems. ? 2010 Copyright SPIE - The International Society for Optical Engineering.Accession Number: 20105013482887 -
Record 167 of
Title:A trace acquisition method of small moving target
Author(s):Ma, Junyong(1); Wen, Desheng(1); Yang, Shaodong(1)Source: ICACTE 2010 - 2010 3rd International Conference on Advanced Computer Theory and Engineering, Proceedings Volume: 5 Issue: DOI: 10.1109/ICACTE.2010.5579516 Published: 2010Abstract:This paper presents a new method for detecting small moving targets from consecutive image sequences. Image sequences are processed to detect targets, assuming that the data samples have been spatially registered. Firstly, Maximum Value Projection and normalization are utilized to reduce the data samples and reject the background clutter. Then, targets are detected using connected component analysis. At last, the velocities of the targets are estimated by centroid localization and least-square regression. A sliding neighborhood operation is performed before target detection. It can greatly reduce the computation while preserving as much target information as possible. The experimental results indicate that this method can efficiently detect the small moving targets and accurately track their traces. Both centroid locating precision and tracking accuracy are within a pixel. ? 2010 IEEE.Accession Number: 20104613374233 -
Record 168 of
Title:Hierarchical segmentation based on a multilevel thresholding
Author(s):Ma, Junyong(1); Wen, Desheng(1); Yang, Shaodong(1); Wang, Liang(1); Zhan, Jianming(1)Source: Proceedings - 2010 3rd International Congress on Image and Signal Processing, CISP 2010 Volume: 3 Issue: DOI: 10.1109/CISP.2010.5648275 Published: 2010Abstract:Segmentation plays an important role in image processing, machine vision, pattern recognition and so on. Numerous segmentation methods based on bi-level thresholding have been proposed, assuming there are only two main populations in an image. However, for a complex image consisting of more populations, a multilevel thresholding is required. This paper presents a new hierarchical segmentation method based on multilevel thresholding. The hierarchical segmentation utilizes an iterative threshold selection method as a basis to partition an image into two regions. Similarly, every region is segmented into two parts. This process continues until a better segmentation is obtained. Several objective measures are considered to evaluate the quality of segmentation. The experimental results indicate the proposed method can obtain an effective segmentation for an image with more populations. ?2010 IEEE.Accession Number: 20105213529034