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Design and detection for the photoelectric device used in the point source transmission testing 期刊论文  OAI收割
Yi Qi Yi Biao Xue Bao/Chinese Journal of Scientific Instrument, 2018, 卷号: 39, 期号: 1, 页码: 92-99
作者:  
Zhang, Ning;  Ye, Lu;  Song, Ying
  |  收藏  |  浏览/下载:28/0  |  提交时间:2019/09/17
Detection ability analysis of ground based imaging polarization detector 期刊论文  OAI收割
optik, 2015, 卷号: 126, 期号: 23, 页码: 4771-4774
作者:  
Yao, Dalei;  Wen, Desheng;  Xue, Jianru;  Qiu, Yuehong;  Xi, Jiangbo
收藏  |  浏览/下载:25/0  |  提交时间:2015/12/25
Improved method of target detection on optoelectronic hybrid joint transform correlator in cluttered scences (EI CONFERENCE) 会议论文  OAI收割
2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China
作者:  
Yang L.;  Yang L.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
A classical joint transform correlator (JTC) usually yields large correlation sidelobes as well as a large correlation peak width  strong zero-order peak  and low diffraction efficiency  which make the detection ability of JTC lower. To overcome these difficulties  firstly  a joint power spectrum (JPS) subtraction technique in Fourier plane was proposed  where reference image power spectrum and object image power spectrum are subtracted from the JPS before inverse Fourier-transform operation  it is obvious that the modified JPS removes the zero-order term. Secondly  a fringe-adjusted filter (FAF) was presented to suppress sidelobes and noises. The modified JPS is multiplied by a FAF before the inverse Fourier-transform operation to obtain the cross-correlation peak. Computer simulations demonstrated the improved method can obviously remove zero-order diffraction and effectively suppress the sidelobes and noises compared with classic JTC  and then improve the detection ability for JTC. Experimental results presented the sharp correlation peak and also confirmed the method effectiveness. (2012) Trans Tech Publications  Switzerland.  
Large-scale synthesis of coordination polymer microdendrites and their application as a sensing platform for fluorescent DNA detection 期刊论文  OAI收割
rsc advances, 2011, 卷号: 1, 期号: 4, 页码: 725-730
Li HL; Zhai JF; Sun XP
收藏  |  浏览/下载:18/0  |  提交时间:2012/06/11
Innovative EDL GNC scheme for precise and safe mars landing missions (EI CONFERENCE) 会议论文  OAI收割
60th International Astronautical Congress 2009, IAC 2009, October 12, 2009 - October 16, 2009, Daejeon, Korea, Republic of
作者:  
Liu Y.;  Zhang L.;  Zhang L.;  Liu Y.;  Liu Y.
收藏  |  浏览/下载:42/0  |  提交时间:2013/03/25
The calibration of faint simulation star magnitude based on single photon count technique (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Imaging Detectors and Applications, June 17, 2009 - June 19, 2009, Beijing, China
作者:  
Xu S.-Y.;  Guo J.;  Guo J.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
A calibration method of faint star magnitude of the star scene simulation device is proposed in this paper. In the research of simulation star magnitude  luminometers and CCD devices are the general calibration devices which are used to measure the illumination intensity and calibrate its magnitude. But if the simulation magnitude is only sixth magnitude  its illumination intensity is only 1.010-8 Lux. This illumination intensity level is the lowest illumination intensity that the commercial luminometer can detect. Hence the simulation star magnitude lower than six magnitude cannot be calibrated by luminoters. Likewise CCD devices also need an additive cooler in this case. When the single photon characteristic is presented due to the low luminosity of simulating light sources  the simulation star magnitude can be calibrated by detecting its photon flux of radiation with the method of single photon count. In this paper the detection principle of single photon based on a compact designed PMT detecting of the radiation level of simulation star magnitude is advanced. Especially a spectrum match method is proved theoretically to be an effective means for selecting PMT photosensitive type. In the case of the detection object of the simulation star in visible wavelength  a analysis indicates that the material of tri-alkali cathode materials its best choice after being compared the Signal-to-Noise of photon detector of several PMT photosensitive materials based on the different spectrum match ratio of different object light sources and different cathode materials. An experiment is employed to show the relationship of control voltage of PMT and its dark counter  the relationship of the environment temperature of PMT and its dark counter  which proves its only decades of CPS at room temperature. The so low dark counter avoids a bulky cooler and is convenient for installing it on the star scene simulation equipment. Finally in the experiment of calibrating the simulation star magnitudes the ability of its calibration is confirmed to reaches up to 12m  meanwhile its calibration error is within 0.2m. 2009 SPIE.  
Intelligent MRTD testing for thermal imaging system using ANN (EI CONFERENCE) 会议论文  OAI收割
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
Sun J.; Ma D.
收藏  |  浏览/下载:25/0  |  提交时间:2013/03/25
The Minimum Resolvable Temperature Difference (MRTD) is the most widely accepted figure for describing the performance of a thermal imaging system. Many models have been proposed to predict it. The MRTD testing is a psychophysical task  for which biases are unavoidable. It requires laboratory conditions such as normal air condition and a constant temperature. It also needs expensive measuring equipments and takes a considerable period of time. Especially when measuring imagers of the same type  the test is time consuming. So an automated and intelligent measurement method should be discussed. This paper adopts the concept of automated MRTD testing using boundary contour system and fuzzy ARTMAP  but uses different methods. It describes an Automated MRTD Testing procedure basing on Back-Propagation Network. Firstly  we use frame grabber to capture the 4-bar target image data. Then according to image gray scale  we segment the image to get 4-bar place and extract feature vector representing the image characteristic and human detection ability. These feature sets  along with known target visibility  are used to train the ANN (Artificial Neural Networks). Actually it is a nonlinear classification (of input dimensions) of the image series using ANN. Our task is to justify if image is resolvable or uncertainty. Then the trained ANN will emulate observer performance in determining MRTD. This method can reduce the uncertainties between observers and long time dependent factors by standardization. This paper will introduce the feature extraction algorithm  demonstrate the feasibility of the whole process and give the accuracy of MRTD measurement.