2015
2015
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Record 193 of
Title:Robust Discrete Spectral Hashing for Large-Scale Image Semantic Indexing
Author(s):Yang, Yang(1); Shen, Fumin(1); Shen, Heng Tao(1,2); Li, Hanxi(3); Li, Xuelong(4)Source: IEEE Transactions on Big Data Volume: 1 Issue: 4 DOI: 10.1109/TBDATA.2016.2516024 Published: December 1, 2015Abstract:In big data era, the ever-increasing image data has posed significant challenge on modern image retrieval. It is of great importance to index images with semantic keywords efficiently and effectively, especially confronted with fast-evolving property of the web. Learning-based hashing has shown its power in handling large-scale high-dimensional applications, such as image retrieval. Existing solutions normally separate the process of learning binary codes and hash functions into two independent stages to bypass challenge of the discrete constraints on binary codes. In this work, we propose a novel unsupervised hashing approach, namely robust discrete hashing (RDSH), to facilitate large-scale semantic indexing of image data. Specifically, RDSH simultaneously learns discrete binary codes as well as robust hash functions within a unified model. In order to suppress the influence of unreliable binary codes and learn robust hash functions, we also integrate a flexible 2,p loss with nonlinear kernel embedding to adapt to different noise levels. Finally, we devise an alternating algorithm to efficiently optimize RDSH model. Given a test image, we first conduct r-nearest-neighbor search based on Hamming distance of binary codes, and then propagate semantic keywords of neighbors to the test image. Extensive experiments have been conducted on various real-world image datasets to show its superiority to the state-of-the-arts in large-scale semantic indexing. ? 2015 IEEE.Accession Number: 20162602535959 -
Record 194 of
Title:A portable swappable method scientific CMOS image data storage system
Author(s):Liu, Wen-Long(1,2); Pi, Hai-Feng(1); Hu, Bing-Liang(1); Gao, Jia-Rui(1,2)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9795 Issue: DOI: 10.1117/12.2208424 Published: 2015Abstract:In the field of deep space exploration, the detector needs high-speed data real-time transmission and large capacity storage. SATA(Serial advanced technology attachment) as a new generation of interface protocols, SATA interface hard disk has the advantages of with large storage capacity, high transmission rate, the cheap price, data is not lost when power supply drop, so it is suitable for used in high speed large capacity data storage system. This paper by using Kintex-7 XCE7K325T XILINK series FPGA, the data of scientific CMOS CIS2521F through the SATA controller is stored in the hard disk. If the hard disk storage is full, it will automatically switch to the next hard disk. ? 2015 SPIE.Accession Number: 20161702279105 -
Record 195 of
Title:Influence of vibration in the airborne celestial navigation system on navigation accuracy
Author(s):Dong, Qiang(1,2); Ma, Caiwen(1); Li, Yan(1); Yang, Xiaoxu(1); Yuan, Hui(1,2)Source: Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University Volume: 36 Issue: 2 DOI: 10.3969/j.issn.1006-7043.201404048 Published: February 25, 2015Abstract:For the issue of the influence of aircraft vibration on the navigation system positioning accuracy based on airborne autonomous celestial navigation system, an analysis of navigation platform vibration influenced from aircraft was preceded. Furthermore, a conclusion was given that the main factor is vibration angular displacement. Next, a single stellar positioning model in the celestial navigation system was established. According to the characteristics of vibration angular displacement, the similar coordinate transformation matrix in the angular displacement compensation was given. The results of vibration experiment and positioning model simulation validated that the angular vibration is the main error propagation to navigation system platform. The positioning error of celestial navigation system is 600 m when vibration angular displacement is 200 s along the x and y axis. ?, 2015, Editorial Board of Journal of HEU. All right reserved.Accession Number: 20151300692218 -
Record 196 of
Title:Optical technologies for space sensor
Author(s):Wang, Hu(1,2); Liu, Jie(2); Xue, Yaoke(2); Liu, Yang(2); Liu, Meiying(2); Wang, Lingguang(2); Yang, Shaodong(2); Lin, Shangmin(2); Chen, Su(2); Luo, Jianjun(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9678 Issue: DOI: 10.1117/12.2197608 Published: 2015Abstract:Space sensors are used in navigation sensor fields. The sun, the earth, the moon and other planets are used as frame of reference to obtain stellar position coordinates, and then to control the attitude of an aircraft. Being the"eyes"of the space sensors, Optical sensor system makes images of the infinite far stars and other celestial bodies. It directly affects measurement accuracy of the space sensor, indirectly affecting the data updating rate. Star sensor technology is the pilot for Space sensors. At present more and more attention is paid on all-day star sensor technology. By day and night measurements of the stars, the aircraft's attitude in the inertial coordinate system can be provided. Facing the requirements of ultra-high-precision, large field of view, wide spectral range, long life and high reliability, multi-functional optical system, we integration, integration optical sensors will be future space technology trends. In the meantime, optical technologies for space-sensitive research leads to the development of ultra-precision optical processing, optical and precision test machine alignment technology. It also promotes the development of long-life optical materials and applications. We have achieved such absolute distortion better than ±1um, Space life of at least 15years of space-sensitive optical system. ? 2015 SPIE.Accession Number: 20161602271437 -
Record 197 of
Title:Color enhancement algorithm for low-quality image based on gamma mapping
Author(s):Guo, Huinan(1); Zhang, Gaopeng(1); Mei, Chao(1); Zhang, Derui(1); Song, Xiaodong(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9794 Issue: DOI: 10.1117/12.2202930 Published: 2015Abstract:Color quality plays an important role in imaging and displaying. For the Low-quality image, we propose a new method in this paper that is based on gamma mapping to improve color contrast and restore color expression of real world scene. The main idea of the proposed approach is that according to human vision characteristics uses logarithm transformation to extend luminance response of image so; meanwhile, adopts the gamma mapping to enhance the contrast of highlight and dark regions. To approve the proposed method, two well-known algorithms are selected and their contrast results are also presented. The results show that the proposed approach performs better than other traditional methods for color restoration which is of good robustness. ? 2015 SPIE.Accession Number: 20161602265261 -
Record 198 of
Title:A Class of Manifold Regularized Multiplicative Update Algorithms for Image Clustering
Author(s):Yang, Shangming(1); Yi, Zhang(2); He, Xiaofei(3); Li, Xuelong(4)Source: IEEE Transactions on Image Processing Volume: 24 Issue: 12 DOI: 10.1109/TIP.2015.2457033 Published: December 1, 2015Abstract: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. ? 2015 IEEE.Accession Number: 20154201388584 -
Record 199 of
Title:Graded index porous optical fibers-dispersion management in terahertz range
Author(s):Ma, Tian(1,2); Markov, Andrey(1); Wang, Lili(1,2); Skorobogatiy, Maksim(1)Source: Optics Express Volume: 23 Issue: 6 DOI: 10.1364/OE.23.007856 Published: March 23, 2015Abstract:A graded index porous optical fiber incorporating an air-hole array featuring variable air-hole diameters and inter-hole separations is proposed, fabricated, and characterized in a view of the fiber potential applications in low-loss, low-dispersion terahertz guidance. The proposed fiber features simultaneously low modal and intermodal dispersions, as well as low loss in the terahertz spectral range. We experimentally demonstrate that graded index porous fibers exhibit smaller pulse distortion, larger bandwidth, and higher excitation efficiency when compared to fibers with uniform porosity. ? 2015 OSA.Accession Number: 20152801025622 -
Record 200 of
Title:Automatic alignment algorithm of high-power laser beam
Author(s):Xu, Rui-Hua(1); He, Jun-Hua(1); Wang, Wei(1); Wang, Zheng-Zhou(1,2); Zhang, Zhi-Jun(1); Zhao, Juan-Ning(2); Ma, Cai-Wen(1)Source: Guangzi Xuebao/Acta Photonica Sinica Volume: 44 Issue: 2 DOI: 10.3788/gzxb20154402.0214002 Published: February 1, 2015Abstract:A quick and high-precision image center locating algorithm based on the difference between the corresponding ellipse's long and short axe method was proposed, to meeting the requirements for high precision and time-saving in real time beam automatic alignment process of the high power laser device. The maximum value of the spot's area is obtained by acting the Big Law Method, 3×3 Neighborhood Method and Eight-Neighborhood Method on the spot image in turn; Lengths of the long and the short axis are obtained by the analyzing the center distance of the maximum spot, and adjust the spot shape by the deviation of the ellipse's long and short axe until to the deviation approach to zero; Through analysis the deviation between the actual spot center and the corresponding reference position, the adjusting steps of stepping motor controlled by the closed-loop control method is obtained, and the automatic alignment is realized. This algorithm is verified in the high-power laser device, the experiment results shows that the alignment time of the main amplification of the optical path is shortened to 15 min, the near-field alignment accuracy is better than 0.2%, and the far-field pointing accuracy is better than 1 μrad, all of them meet the alignment requirements of the high-power laser device. ?, 2015, Chinese Optical Society. All right reserved.Accession Number: 20151100646937 -
Record 201 of
Title:Color constancy technology based on detail description
Author(s):Guo, Huinan(1); Cao, Jianzhong(1); Zhang, Hui(1); Zhou, Zuofeng(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9631 Issue: DOI: 10.1117/12.2197007 Published: 2015Abstract:Color constancy is an important problem in machine vision and image processing fields. We propose a new method in this paper that is based on detail information description to estimate the chromaticity of the light source and restore the real color property of captured images. The main idea of the proposed approach is that according to human vision characteristics use the interest information in an image to estimate the lighting condition of real scene. To approve the proposed method, two well-known algorithms are selected and their contrast results are also presented. It is shown in this paper that the proposed approach performs better than other traditional methods for color constancy most of the time. ? 2015 SPIE.Accession Number: 20154501514863 -
Record 202 of
Title:Calibration and compensation of angular error in laser tracker
Author(s):She, Wenji(1,2); Gao, Limin(1); Yang, Yongqing(1); Zhou, Liang(2)Source: Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument Volume: 36 Issue: DOI: Published: December 1, 2015Abstract:Following polar cordinate mesuring method with single apparatus, and combining precise laser ranging technology and high-accuracy angular measure technology, Laser tracker have excellent ability in large-scale metrology. Angular mesure system adopt with rotory grating, which is a non-contacat digital measure system integral with optical, mechanical and electronic technology. Accompanied with simple structure, high precision and fast measure speed, rotory grating have widespread used in epuipment of precision angular measurement. According to analysis all type error of rotary grating such as dividing error in manufacture, subdivision error in electroncis, wobbling of shaft and eccentricity of grating in mounting, a error compensation model were established through Fourier analysis method, adopted this compensation, the angular error reduced form 10 arc-second to 0.8 arc-second measured by one grating readhead, this measuring accuracy correspondent to diametrical measurement by two grating readhead, which characteristic ultra-high accuracy of 0.3 arc-second. ? 2015, Editorial Office of Chinese Journal of Scientific Instrument. All right reserved.Accession Number: 20160501858776 -
Record 203 of
Title:A real-time camera calibration system based on OpenCV
Author(s):Zhang, Hui(1); Wang, Hua(1); Guo, Huinan(1); Ren, Long(1); Zhou, Zuofeng(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9631 Issue: DOI: 10.1117/12.2197304 Published: 2015Abstract:Camera calibration is one of the essential steps in the computer vision research. This paper describes a real-time OpenCV based camera calibration system, and developed and implemented in the VS2008 environment. Experimental results prove that the system to achieve a simple and fast camera calibration, compared with MATLAB, higher precision and does not need manual intervention, and can be widely used in various computer vision system. ? 2015 SPIE.Accession Number: 20154501514655 -
Record 204 of
Title:Calibration method of focal plane for static multi-star simulator
Author(s):Li, Zhaohui(1,2); Zhao, Jianke(1); Xu, Liang(1)Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 9795 Issue: DOI: 10.1117/12.2208000 Published: 2015Abstract:The calibration work was important to the development of star sensor, improving the accuracy of star simulator was very important for the calibration of star sensor. In reality, being limited in manufacturing technology, assembling and testing facility and so on, it was very difficult to achieve the precision of design theory, especially the star angular distance. In this paper, from the accuracy of angular distance of star simulator, combined with the installation practice, through real-time monitoring of theodolite, and put forward a quantitative method of focusing. Experimentation have shown that the method can realize the accurately focusing of star simulator, all the angle distance error finally were less than 7.72'', and can improve the installation efficiency. ? 2015 SPIE.Accession Number: 20161702279093