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Record 97 of
Title:New segmentation-based tone mapping algorithm for high dynamic range image
Author(s):Duan, Weiwei(1,2); Guo, Huinan(1); Zhou, Zuofeng(1,2); Huang, Huimin(1); Cao, Jianzhong(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10420 Issue: DOI: 10.1117/12.2282031 Published: 2017
Abstract:The traditional tone mapping algorithm for the display of high dynamic range (HDR) image has the drawback of losing the impression of brightness, contrast and color information. To overcome this phenomenon, we propose a new tone mapping algorithm based on dividing the image into different exposure regions in this paper. Firstly, the over-exposure region is determined using the Local Binary Pattern information of HDR image. Then, based on the peak and average gray of the histogram, the under-exposure and normal-exposure region of HDR image are selected separately. Finally, the different exposure regions are mapped by differentiated tone mapping methods to get the final result. The experiment results show that the proposed algorithm achieve the better performance both in visual quality and objective contrast criterion than other algorithms. ? 2017 SPIE.
Accession Number: 20174104255072
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Record 98 of
Title:Modeling Information Diffusion over Social Networks for Temporal Dynamic Prediction
Author(s):Li, Dong(1,2); Zhang, Shengping(3); Sun, Xin(3); Zhou, Huiyu(4); Li, Sheng(5); Li, Xuelong(6)
Source: IEEE Transactions on Knowledge and Data Engineering Volume: 29 Issue: 9 DOI: 10.1109/TKDE.2017.2702162 Published: September 1, 2017
Abstract:Modeling the process of information diffusion is a challenging problem. Although numerous attempts have been made in order to solve this problem, very few studies are actually able to simulate and predict temporal dynamics of the diffusion process. In this paper, we propose a novel information diffusion model, namely GT model, which treats the nodes of a network as intelligent and rational agents and then calculates their corresponding payoffs, given different choices to make strategic decisions. By introducing time-related payoffs based on the diffusion data, the proposed GT model can be used to predict whether or not the user's behaviors will occur in a specific time interval. The user's payoff can be divided into two parts: social payoff from the user's social contacts and preference payoff from the user's idiosyncratic preference. We here exploit the global influence of the user and the social influence between any two users to accurately calculate the social payoff. In addition, we develop a new method of presenting social influence that can fully capture the temporal dynamics of social influence. Experimental results from two different datasets, Sina Weibo and Flickr demonstrate the rationality and effectiveness of the proposed prediction method with different evaluation metrics. ? 1989-2012 IEEE.
Accession Number: 20173804172573
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Record 99 of
Title:Research progress on fabrication technology of space mirror using carbon fiber composite
Author(s):Yang, Zhiyong(1,2); Zhang, Boming(1); Xie, Yongjie(3); Zhang, Jianbao(2); Tang, Zhanwen(2); Sun, Baogang(2)
Source: Fuhe Cailiao Xuebao/Acta Materiae Compositae Sinica Volume: 34 Issue: 1 DOI: 10.13801/j.cnki.fhclxb.20160328.012 Published: January 1, 2017
Abstract:Excellent specific stiffness, good thermal stability and diversiform designability are obvious characteristics of carbon fiber composite(CFRP), which make it a new ideal material for the lightweight reflectors, especially for large diameter and high resolution space reflectors. The present situation of the research of optical mirrors in our country and on abroad was briefly introduced. Then according to the characteristics of mirrors, selection requirements of carbon fiber composite for mirror and foreign prepreg system commonly used were introduced. Manufacturing method of carbon fiber composite optical mirror is different from that of the traditional optical materials. Usually, the high efficiency, fast and low cost replication process is used for carbon fiber composite mirror. The optical replication of carbon fiber composite mirrors, and factors affecting the accuracy of replicated mirror were emphatically introduced, and the factors including the mould, prepreg layup, deformation of mirror, fiber print-through, dimensional stability and size of mirror, etc. And the corresponding control measures to reduce the influence degree were put forward for the former five factors. Causes and solutions of mirror fiber print-through, and the key to control dimensional stability of mirror were focused. ? 2017, Chinese Society for Composite Materials. All right reserved.
Accession Number: 20171203466158
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Record 100 of
Title:A Method for Achieving Super Resolution Vibrational Sum-Frequency Generation Microscopy by Structured Illumination
Author(s):Li, Ya-Hui(1,2,3); Chen, Dan-Ni(2,4,5); Niu, Han-Ben(2,4,5)
Source: IEEE Photonics Journal Volume: 9 Issue: 3 DOI: 10.1109/JPHOT.2017.2705124 Published: June 2017
Abstract:A scheme was proposed to achieve wide-field vibrational sum-frequency generation (SFG) microscopy with subdiffraction-limited resolution in one dimension. In this approach, samples are illuminated with a structured visible field and a uniform IR field to induce vibrational sum-frequency generation. With five raw images acquired at five different phases of the visible stripe pattern, a super-resolved vibrational SFG (SR-SFG) image with the resolution triple to that of the original can be reconstructed. Theoretical framework describing the coherent image formation and reconstruction scheme for the SR-SFG imaging system was derived and carried out with numerical simulations to investigate its imaging performance. With a typical imaging system, the lateral resolution was improved from 390 nm of the conventional SFG imaging system, to around 130 nm of the SR-SFG imaging system. ? 2009-2012 IEEE.
Accession Number: 20173504101270
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Record 101 of
Title:Design of an off-Axis reflective zoom optical system
Author(s):Guo, Zhanli(1,2); Yang, Hongtao(1); Mei, Chao(1); Yan, Aqi(1)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10462 Issue: DOI: 10.1117/12.2285188 Published: 2017
Abstract:With the limit of optical materials, it is difficult to design zoom optical systems which have long focal length by refractive systems with a simple configuration. All-reflective zoom optical systems could be lightweighted, compact and free of chromatic aberrations, and reflective optical systems can be unobscured by off-Axis mirrors and have very good application foreground. In this paper, an all-reflective zoom optical system was designed, the all-reflective zoom optical system worked in the band of 400~1000nm, the diameter of the pupil was 100mm, the F number was 6~15, focal length varied from 600~1500mm, field of view (FOV) was 2°×0.8°~0.8°×0.48°. The pixel size of detector was 10×10μm. The result showed that MTF was higher than 0.3 at 50lp/mm and the quality of the optical system approached the diffraction limit, which met the design demand. ? 2017 SPIE.
Accession Number: 20180404671170
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Record 102 of
Title:Adaptive synchronization of delayed reaction-diffusion neural networks with unknown non-identical time-varying coupling strengths
Author(s):Li, Junmin(1); He, Chao(1); Zhang, Weiyuan(2); Chen, Minglai(1,3)
Source: Neurocomputing Volume: 219 Issue: DOI: 10.1016/j.neucom.2016.09.006 Published: January 5, 2017
Abstract:This paper concerns the asymptotic synchronization of delayed reaction-diffusion neural networks (RDNNs) with unknown nonidentical time-varying coupling strengths, where the time-varying coupling strengths are consist of continuous time-varying periodic parameters and time-invariant nonnegative parameters. By utilizing a novel adaptive approach, the differential-difference type adaptive laws of coupling strengths and adaptive controller are designed such that the nonidentical RDNNs are asymptotic synchronization. The sufficient conditions dependent on the reaction-diffusion terms are derived by constructing a novel Lyapunov-Krasovskii-like composite energy functional (CEF) and using Barbalat's lemma. Finally, a simulation example is provided to illustrate the effectiveness of the developed approach. ? 2016 Elsevier B.V.
Accession Number: 20164603021588
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Record 103 of
Title:Multi-parameter calibration of streak/framing camera based on integrated optical system with delay and attenuation modules
Author(s):Wu, Bingjing(1); He, Junhua(1); Qi, Wenbo(1); Yuan, Zheng(2)
Source: Optik Volume: 138 Issue: DOI: 10.1016/j.ijleo.2017.03.049 Published: June 1, 2017
Abstract:We demonstrate a multi-parameter calibration method of the streak camera and the framing camera with the help of beam division delay and attenuation devices in an integrated optical system based on sub-picosecond short-pulse UV laser. In the designed optical scheme, the four operating modes employed the optical delay, beam division delay and attenuation, and etalon modules can be switched to synchronize the UV laser pulse with the trigger signal of diagnosis instruments, calibrate the temporal resolution and dynamic range of framing cameras, and correct the sweep speed of streak cameras, respectively. The results show that the delay time error of ±0.1?ns in the optical delay module, the uniform distribution of sub-beams with the delay time precision of ±0.03?ps and isocon descending energy in the beam division delay and attenuation modules, and pulse broadening of ～22% in the whole system are achieved. In the meantime, the experiment results display the sweep speed of 1.2?ps/pixel in a streak camera and the dynamic range of 131 in a framing camera. The proposed folding optical system with high-precision, low-loss and multi-function can be extensively applied in the temporal calibration of diagnosis instruments such as streak cameras and framing cameras. ? 2017 Elsevier GmbH
Accession Number: 20171403515182
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Record 104 of
Title:High-precision test station for stray light based on point source transmittance
Author(s):Chen, Qin-Fang(1); Ma, Zhen(1); Wang, Hu(1); Li, Xin-Yao(2); Pang, Zhi-Hai(1)
Source: Guangxue Jingmi Gongcheng/Optics and Precision Engineering Volume: 25 Issue: DOI: 10.3788/OPE.20172514.0039 Published: December 1, 2017
Abstract:The increased demand for detection of dim targets in deep space and the rapid development of low threshold space-based sensors have required greater suppression performance of stay light and higher test accuracy. A stray light test station based on Point Source Transmittance (PST) is built. The station allows an measuring aperture up to 1 m and waveband from the visible to the infrared. In the station, the turntable instrument is allowed to scan ±110° in azimuth, and ±15° in picth. The test station is all black with dimensions of 28 m×8 m×9 m. In order to control light scattered from the collimator, the primary mirror with less than 2 nm RMS roughness is manufactured. A double cylindrical chamber is employed to direct and attenuate the scattered light from the system. In addition, a clean room in 1 000 class is utilized to filter air to reduce light scattered from particles in the air. Analysis and measurements show that the test station can measure point PST as low as 10-7 at visible wavelengths, and 10-6 at infrared wavelengths. Its test accuracy |lg(measurement value /true value)| is less than 0.5. ? 2017, Science Press. All right reserved.
Accession Number: 20180504692848
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Record 105 of
Title:Synchronous acquisition method based on feature recognition of sequence images in online vision inspection
Author(s):Xin, Jiang(1,2); Hua, Li(2); Jie, Liu(1,2)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 10256 Issue: DOI: 10.1117/12.2257657 Published: 2017
Abstract:In order to meet the requirements of synchronous image acquisition in online industrial vision inspection, a new method based on image feature recognition is proposed. According to the method, the spatial characteristic information of sequence images has been calculated, and an algorithm under multi-constrained conditions which based on the trend of feature values of sequence images is established. The synchronous target image in online inspection is acquired by the trigger signal which was obtained by the algorithm under the condition of no dependence on external attachment. The method does not need to rely on the external position feedback device, and reduces the hardware cost. The algorithm has a better synchronization precision and adaptability, and has been successfully applied in practice. ? 2017 SPIE.
Accession Number: 20171703607530
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Record 106 of
Title:Self-weighted multiview clustering with multiple graphs
Author(s):Nie, Feiping(1); Li, Jing(1); Li, Xuelong(2)
Source: IJCAI International Joint Conference on Artificial Intelligence Volume: 0 Issue: DOI: 10.24963/ijcai.2017/357 Published: 2017
Abstract:In multiview learning, it is essential to assign a reasonable weight to each view according to the view importance. Thus, for multiview clustering task, a wise and elegant method should achieve clustering multiview data while learning the view weights. In this paper, we propose to explore a Laplacian rank constrained graph, which can be approximately as the centroid of the built graph for each view with different confidences. We start our work with a natural thought that the weights can be learned by introducing a hyperparameter. By analyzing the weakness of this way, we further propose a new multiview clustering method which is totally selfweighted. More importantly, once the target graph is obtained in our models, we can directly assign the cluster label to each data point and do not need any postprocessing such as K-means in standard spectral clustering. Evaluations on two synthetic datasets indicate the effectiveness of our methods. Compared with several representative graphbased multiview clustering approaches on four realworld datasets, the proposed methods achieve the better performances and our new clustering method is more practical to use.
Accession Number: 20174304308749
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Record 107 of
Title:A novel ZVS high voltage power supply for micro-channel plate photomultiplier tubes
Author(s):Pei, Chengquan(1); Tian, Jinshou(2); Liu, Zhen(1); Qin, Hong(3); Wu, Shengli(1)
Source: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Volume: 851 Issue: DOI: 10.1016/j.nima.2017.01.044 Published: April 11, 2017
Abstract:A novel resonant high voltage power supply (HVPS) with zero voltage switching (ZVS), to reduce the voltage stress on switching devices and improve conversion efficiency, is proposed. The proposed HVPS includes a drive circuit, a transformer, several voltage multiplying circuits, and a regulator circuit. The HVPS contains several secondary windings that can be precisely regulated. The proposed HVPS performed better than the traditional resistor voltage divider, which requires replacing matching resistors resulting in resistor dispersibility in the Micro-Channel Plate (MCP). The equivalent circuit of the proposed HVPS was established and the operational principle analyzed. The entire switching element can achieve ZVS, which was validated by a simulation and experiments. The properties of this HVPS were tested including minimum power loss (240?mW), maximum power loss (1?W) and conversion efficiency (85%). The results of this research are that the proposed HVPS was suitable for driving the micro-channel plate photomultiplier tube (MCP-PMT). It was therefore adopted to test the MCP-PMT, which will be used in Daya Bay reactor neutrino experiment II in China. ? 2017 Elsevier B.V.
Accession Number: 20170603336371
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Record 108 of
Title:AR(p) dynamic catastrophe ranking method of target threat assessment under the loss of data
Author(s):Tang, Xin(1); Yang, Jianjun(2); Feng, Song(3); Ren, Baoxiang(2)
Source: Xi Tong Gong Cheng Yu Dian Zi Ji Shu/Systems Engineering and Electronics Volume: 39 Issue: 5 DOI: 10.3969/j.issn.1001-506X.2017.05.17 Published: May 1, 2017
Abstract:For the problems of the loss of observation data, the hardness on overall consideration of dynamic threat situation of the coming target, the need of confirming index weights of most existing methods and too much rely on expertise, the AR(p) dynamic catastrophe ranking method of target threat assessment is proposed by combining the AR(p) predicting model, time series weight and catastrophe theory. The AR(p) model is used to predict the missing target data on time series, which provides the basic data for threat assessment using all times' data. Time series weight is gained by the inverse form of the Poisson distribution, and the target associating information of the current time and the former time is comprehensively considered. The core thoughts of catastrophe ranking is abstracted based on the catastrophe theory, and the function of sub layer indexes on its upper layer indexes in the target threat assessment index system is attributed to the function of control variable on state variable. The degree of this function is solved by the normalization formulae, and the target threat assessment value is acquired through the bottom layer to the top layer according to this mode. The experiment result indicates that the AR(p) dynamic catastrophe ranking method can be used for target threat assessment under the loss of target data, which is more close to the actual combat. It is unnecessary to compute the weights of all indexes, which is concise, efficient, and easy to implement. In addition, the assessment result is more reasonable and has a certain application value due to the comprehensive consideration of the dynamic threat situation of targets. ? 2017, Editorial Office of Systems Engineering and Electronics. All right reserved.
Accession Number: 20173404070391
