2017

• Record 469 of
  
  Title:Exploring models and data for remote sensing image caption generation
  
  Author(s):Lu, Xiaoqiang(1,2); Wang, Binqiang(1,2); Zheng, Xiangtao(1,2); Li, Xuelong(1,2)
  Source: arXiv  Volume:   Issue:   DOI:   Published: December 21, 2017  
  Abstract:Inspired by recent development of artificial satellite, remote sensing images have attracted extensive attention. Recently, noticeable progress has been made in scene classification and target detection. However, it is still not clear how to describe the remote sensing image content with accurate and concise sentences. In this paper, we investigate to describe the remote sensing images with accurate and flexible sentences. First, some annotated instructions are presented to better describe the remote sensing images considering the special characteristics of remote sensing images. Second, in order to exhaustively exploit the contents of remote sensing images, a large-scale aerial image dataset is constructed for remote sensing image caption. Finally, a comprehensive review is presented on the proposed dataset to fully advance the task of remote sensing caption. Extensive experiments on the proposed dataset demonstrate that the content of the remote sensing image can be completely described by generating language descriptions. The dataset is available at https://github.com/201528014227051/RSICD_optimal. Copyright © 2017, The Authors. All rights reserved.
  Accession Number: 20200146197
• Record 470 of
  
  Title:Variable curvature mirror having variable thickness: Design and fabrication
  
  Author(s):Zhao, Hui(1); Xie, Xiaopeng(2); Xu, Liang(1); Ding, Jiaoteng(1); Shen, Le(1); Gong, Jie(3)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 10463  Issue:   DOI: 10.1117/12.2285184  Published: 2017  
  Abstract:Variable curvature mirror (VCM) can change its curvature radius dynamically and is usually used to correct the defocus and spherical aberration caused by thermal lens effect to improve the output beam quality of high power solid-state laser. Recently, the probable application of VCM in realizing non-moving element optical zoom imaging in visible band has been paid much attention. The basic requirement for VCM lies in that it should provide a large enough saggitus variation and still maintains a high enough surface figure at the same time. Therefore in this manuscript, by combing the pressurization based actuation with a variable thickness mirror design, the purpose of obtaining large saggitus variation and maintaining quite good surface figure accuracy at the same time could be achieved. A prototype zoom mirror with diameter of 120mm and central thickness of 8mm is designed, fabricated and tested. Experimental results demonstrate that the zoom mirror having an initial surface figure accuracy superior to 1/80λ could provide bigger than 36um saggitus variation and after finishing the curvature variation its surface figure accuracy could still be superior to 1/40λ with the spherical aberration removed, which proves that the effectiveness of the theoretical design. © 2017 SPIE.
  Accession Number: 20180304654861
• Record 471 of
  
  Title:Analysis of the influence of diattenuation on optical imaging system by using the theory of vector plane wave spectrum
  
  Author(s):Zhang, Min-Rui(1,2); He, Zheng-Quan(1); Wang, Tao(1); Tian, Jin-Shou(1)
  Source: Wuli Xuebao/Acta Physica Sinica  Volume: 66  Issue: 8  DOI: 10.7498/aps.66.084202  Published: April 20, 2017  
  Abstract:In most of the researches of polarization aberration, the influence of diattenuation is not large enough to affect imaging quality evidently. However, the modulation transfer function decreases when optical elements with complex planar dielectric structures and low transmittance, such as beam-splitter and optical modulator, are introduced into an imaging system. In this paper, a vector optical model in Descartes coordinate system is proposed based on the concept of vector plane wave spectrum (VPWS). The results of calculation show that the VPWS model is consistent with Debye model. Compared with Debye vector diffraction integral, the VPWS method is more suitable to the description of the PA introduced by planar optical device with opaque mask, such as larger surface quantum-confined-stark-effect electro-absorption modulator, which is used to modulate the light collected by optical antenna of time-of-flight (TOF) depth system or modulating-retroreflector free-space-optical communication system. In order to simplify the calculation and obtain the conclusion of the change in imaging quality directly, the formula of optical transfer function is decomposed into three parts (TE component, TM component and the correlation of them) instead of polynomial expansion of pupil function. The influences of diattenuation on MTF is studied globally and locally in a range of cut-off frequency of optical imaging system (2NA/λ). Allowance of diattenuation is analysed by numerical calculation, and a mathematical expression is derived. The result shows that the change of diattenuation can be neglected when the spatial frequency v is less than 0.2NA/λ, and the range of allowance decreases with the increase of spatial frequency. According to numerical calculation shown in Fig.7 and the derived formulas (15) and (16), the ratios of reflection/transmission coefficient of s-light and p-light √Dα should range respectively from 0.63 to 1.6(0.2NA/λ 0.8NA/λ ) when the MTF is required to be not less than 90% of the value in ideal diffraction-limited system. The range of allowance becomes larger gradually with the increase of angle θn between the normal of optical interface n and the optical axis of imaging system z. If a polarization beam splitter is considered, √Dα→∞,θn sin-1 NA should be greater than 1-3. © 2017 Chinese Physical Society.
  Accession Number: 20172503802226
• Record 472 of
  
  Title:Robust Joint Graph Sparse Coding for Unsupervised Spectral Feature Selection
  
  Author(s):Zhu, Xiaofeng(1); Li, Xuelong(2); Zhang, Shichao(3); Ju, Chunhua(3); Wu, Xindong(4)
  Source: IEEE Transactions on Neural Networks and Learning Systems  Volume: 28  Issue: 6  DOI: 10.1109/TNNLS.2016.2521602  Published: June 2017  
  Abstract:In this paper, we propose a new unsupervised spectral feature selection model by embedding a graph regularizer into the framework of joint sparse regression for preserving the local structures of data. To do this, we first extract the bases of training data by previous dictionary learning methods and, then, map original data into the basis space to generate their new representations, by proposing a novel joint graph sparse coding (JGSC) model. In JGSC, we first formulate its objective function by simultaneously taking subspace learning and joint sparse regression into account, then, design a new optimization solution to solve the resulting objective function, and further prove the convergence of the proposed solution. Furthermore, we extend JGSC to a robust JGSC (RJGSC) via replacing the least square loss function with a robust loss function, for achieving the same goals and also avoiding the impact of outliers. Finally, experimental results on real data sets showed that both JGSC and RJGSC outperformed the state-of-the-art algorithms in terms of κ-nearest neighbor classification performance. © 2016 IEEE.
  Accession Number: 20161102082260
• Record 473 of
  
  Title:Design of low noise imaging system
  
  Author(s):Hu, Bo(1,2); Chen, Xiaolai(1,2)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 10459  Issue:   DOI: 10.1117/12.2285716  Published: 2017  
  Abstract:In order to meet the needs of engineering applications for low noise imaging system under the mode of global shutter, a complete imaging system is designed based on the SCMOS (Scientific CMOS) image sensor CIS2521F. The paper introduces hardware circuit and software system design. Based on the analysis of key indexes and technologies about the imaging system, the paper makes chips selection and decides SCMOS + FPGA+ DDRII+ Camera Link as processing architecture. Then it introduces the entire system workflow and power supply and distribution unit design. As for the software system, which consists of the SCMOS control module, image acquisition module, data cache control module and transmission control module, the paper designs in Verilog language and drives it to work properly based on Xilinx FPGA. The imaging experimental results show that the imaging system exhibits a 2560∗2160 pixel resolution, has a maximum frame frequency of 50 fps. The imaging quality of the system satisfies the requirement of the index. © 2017 COPYRIGHT SPIE.
  Accession Number: 20180204633874
• Record 474 of
  
  Title:Rearranging the lenslet array of the compact passive interference imaging system with high resolution
  
  Author(s):Liu, Gang(1,2); Wen, Desheng(1); Song, Zongxi(1)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 10463  Issue:   DOI: 10.1117/12.2283216  Published: 2017  
  Abstract:With the development of aeronautics and astronautics, higher resolution requirement of the telescope was necessary. However, the increase in resolution of conventional telescope required larger apertures, whose size, weight and power consumption could be prohibitively expensive. This limited the further development of the telescope. This paper introduced a new imaging technology using interference-Compact Passive Interference Imaging Technology with High Resolution, and proposed a rearranging method for the arrangement of the lenslet array to obtain continuously object spatial frequency. © 2017 SPIE.
  Accession Number: 20180304654848
• Record 475 of
  
  Title:Design of CMOS imaging system based on FPGA
  
  Author(s):Hu, Bo(1,2); Chen, Xiaolai(1,2)
  Source: Proceedings of SPIE - The International Society for Optical Engineering  Volume: 10459  Issue:   DOI: 10.1117/12.2285248  Published: 2017  
  Abstract:In order to meet the needs of engineering applications for high dynamic range CMOS camera under the rolling shutter mode, a complete imaging system is designed based on the CMOS imaging sensor NSC1105. The paper decides CMOS+ADC+FPGA+Camera Link as processing architecture and introduces the design and implementation of the hardware system. As for camera software system, which consists of CMOS timing drive module, image acquisition module and transmission control module, the paper designs in Verilog language and drives it to work properly based on Xilinx FPGA. The ISE 14.6 emulator ISim is used in the simulation of signals. The imaging experimental results show that the system exhibits a 1280∗1024 pixel resolution, has a frame frequency of 25 fps and a dynamic range more than 120dB. The imaging quality of the system satisfies the requirement of the index. © 2017 COPYRIGHT SPIE.
  Accession Number: 20180204633870
• Record 476 of
  
  Title:Simultaneous, real-time, chromatic polarimetric imaging technology with full-polarization-state detection
  
  Author(s):Ju, Hai-Juan(1,2); Liang, Jian(1,2); Zhang, Wen-Fei(1,2); Bai, Zhao-Feng(1); Ren, Li-Yong(1); Qu, En-Shi(1)
  Source: Hongwai Yu Haomibo Xuebao/Journal of Infrared and Millimeter Waves  Volume: 36  Issue: 6  DOI: 10.11972/j.issn.1001-9014.2017.06.018  Published: December 1, 2017  
  Abstract:As a new kind of optical imaging technology, polarimetric imaging can efficiently increase the detection dimension of the information by detecting the polarization properties of the optical wave. This is useful for obtaining the target information comprehensively and accurately. Firstly, the method of polarization imaging detecting was introduced and the typical polarization imaging systems are reviewed in this paper. Then, based on Stokes Vector, a simultaneous, real-time, division of aperture chromatic polarimetric imaging camera with full-polarization-state detection was introduced in detail. Finally, the experimental results of full polarimetric imaging and polarimetric dehazing imaging using this camera were demonstrated. The experimental results indicate that the polarimetric imaging technology of full polarization states simultaneous detecting has obvious advantages on developing the detecting distance and acquiring the detail features, so it can provide important supplement for modern optical imaging system. © 2017, Science Press. All right reserved.
  Accession Number: 20181304958855
• Record 477 of
  
  Title:Research on Mural Painting Appreciatione Based on Spectral Imaging and Spectral Analysis
  
  Author(s):Xu, Wen-Zhong(1); Tang, Xing-Jia(2); Zhang, Geng(2); Yang, Fan-Chao(2); Huang, Xin(2); Li, Xia(2); Liu, Dai-Yun(3); Zhao, Xi-Chen(3)
  Source: Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis  Volume: 37  Issue: 10  DOI: 10.3964/j.issn.1000-0593(2017)10-3235-07  Published: October 1, 2017  
  Abstract:For the technology requirements of appreciating mural paintings, according to the advantages of spectral imaging and spectral analysis, the usages of spectral imaging in appreciating mural paintings were discussed, which could improve the traditional expert experience identification method by providing more information in the appreciation and assessment. Spectral method is an important scientific analysis method with many characteristics, like non-contact, lossless, scientific, accurate and quantifiable, which can be used to appreciate mural paintings. Firstly, the application was analyzed from different functions. Secondly, the measurements of mural paintings in HAN XIU tomb were processed by spectral analysis, primary component analysis, independent component analysis, relevance judgment and interactive processing, which were for proving the real affection of the theory analysis. At last, based on the experiments, some key technologies were summarized, for example, normalized measurements, analysis of characters of image and spectral data, processer of image and spectral data. The experiment results showed that the spectral imaging and analysis were useful for the recognition of pigment, the extraction of hidden information, the enhancement of weak information, and the classification and recognition of different properties. Meanwhile, some exploratory works can be unfolded, like modified child analysis, repairing of paintings (such as repairing mural paintings in HAN XIU tomb). © 2017, Peking University Press. All right reserved.
  Accession Number: 20181004855823
• Record 478 of
  
  Title:Study on resin layer polishing of carbon fiber mirror based on ion beam figuring
  
  Author(s):Ding, Jiao Teng(1,2); Fan, Xue Wu(1); Xu, Liang(1); Ma, Zhen(1); Xie, Yong Jie(1); Wang, Yong Jie(1); Luo, Yao(3)
  Source: ICCM International Conferences on Composite Materials  Volume: 2017-August  Issue:   DOI:   Published: 2017  
  Abstract:Based on the advantages of stress-free and non-liquid environment, ion beam polishing is the ideal processing technology for the Resin modified layer polishing of the carbon fiber mirror. Since the glass transition temperature of the resin is low, the energy absorbed by the surface of the mirror during ion beam processing can cause localized high temperatures, which can lead to the risk of resin softening. The finite element analysis software was used to simulate the heat transfer process of Ion beam acting on the resin modified layer. The optimum process parameters of the ion beam polishing were determined. At the same time, the resin layer surface polishing test was completed. The experimental results show that the surface polishing of the resin modified layer can be achieved by ion beam processing, and it has the convergence property and the correctness of the theoretical model is Verified. © 2017 International Committee on Composite Materials. All rights reserved.
  Accession Number: 20183705811725
• Record 479 of
  
  Title:Coarse-to-Fine Learning for Single-Image Super-Resolution
  
  Author(s):Zhang, Kaibing(1); Tao, Dacheng(2); Gao, Xinbo(3); Li, Xuelong(4); Li, Jie(5)
  Source: IEEE Transactions on Neural Networks and Learning Systems  Volume: 28  Issue: 5  DOI: 10.1109/TNNLS.2015.2511069  Published: May 2017  
  Abstract:This paper develops a coarse-to-fine framework for single-image super-resolution (SR) reconstruction. The coarse-to-fine approach achieves high-quality SR recovery based on the complementary properties of both example learning-and reconstruction-based algorithms: example learning-based SR approaches are useful for generating plausible details from external exemplars but poor at suppressing aliasing artifacts, while reconstruction-based SR methods are propitious for preserving sharp edges yet fail to generate fine details. In the coarse stage of the method, we use a set of simple yet effective mapping functions, learned via correlative neighbor regression of grouped low-resolution (LR) to high-resolution (HR) dictionary atoms, to synthesize an initial SR estimate with particularly low computational cost. In the fine stage, we devise an effective regularization term that seamlessly integrates the properties of local structural regularity, nonlocal self-similarity, and collaborative representation over relevant atoms in a learned HR dictionary, to further improve the visual quality of the initial SR estimation obtained in the coarse stage. The experimental results indicate that our method outperforms other state-of-the-art methods for producing high-quality images despite that both the initial SR estimation and the followed enhancement are cheap to implement. © 2012 IEEE.
  Accession Number: 20160902031393
• Record 480 of
  
  Title:A robust stereo matching algorithm based on improved epipolar distance transformation
  
  Author(s):Yue, Qi(1,2,3); Ma, Caiwen(1); Cao, Xiaoqian(2,3,4)
  Source: Optik  Volume: 130  Issue:   DOI: 10.1016/j.ijleo.2016.11.054  Published: February 1, 2017  
  Abstract:Aim to the problem of initial epipolar distance transformation algorithm is sensitive to illumination and depth discontinuous, an improved stereo matching algorithm is proposed. In Delta-Gama log-chromaticity space, Gamma correction coefficient is computed firstly according to raw disparity map which is used to Modified the similarity function bandwidth. Secondly, by employing image structure and color features, the segment of epipolar is obtained adaptively. At last, final disparity map is acquired by belief propagation method. Experimental results demonstrate the effectiveness of the proposed transform in illumination change regions and discontinuities regions. The matching rate of proposed algorithm is improved about 60%, comparing with the initial epipolar distance transformation algorithm and state-of-art algorithm such as ANCC(Adaptive Normalized Cross Correlation). © 2016 Elsevier GmbH
  Accession Number: 20164703040835