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Impacts of climate change on water erosion: A review 期刊论文  OAI收割
EARTH-SCIENCE REVIEWS, 2016, 卷号: 163, 页码: 94-117
作者:  
Li, Zhiying;  Fang, Haiyan
  |  收藏  |  浏览/下载:20/0  |  提交时间:2019/09/26
Impacts of climate change on water erosion: A review 期刊论文  OAI收割
EARTH-SCIENCE REVIEWS, 2016, 卷号: 163, 页码: 94-117
作者:  
Li, Zhiying;  Fang, Haiyan
  |  收藏  |  浏览/下载:12/0  |  提交时间:2019/09/26
Impacts of climate change on water erosion: A review 期刊论文  OAI收割
EARTH-SCIENCE REVIEWS, 2016, 卷号: 163, 页码: 94-117
作者:  
Li, Zhiying;  Fang, Haiyan
  |  收藏  |  浏览/下载:7/0  |  提交时间:2019/09/26
The new approach for infrared target tracking based on the particle filter algorithm (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者:  
Sun H.;  Han H.-X.;  Sun H.
收藏  |  浏览/下载:64/0  |  提交时间:2013/03/25
Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring  precision  and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection  the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure  but in order to capture the change of the state space  it need a certain amount of particles to ensure samples is enough  and this number will increase in accompany with dimension and increase exponentially  this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining"  we expand the classic Mean Shift tracking framework.Based on the previous perspective  we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis  Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism  used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation  and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information  this approach also inhibit interference from the background  ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).  
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:40/0  |  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.