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	Evaluation of spatial upscaling methods based on remote sensing data with multiple spatial resolutions (EI CONFERENCE) 会议论文 OAI收割 Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states Ren R.; Gu L.; Cao J.; Chen H.; Sun J. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 In most applications of remote sensing data special spatial information is required from a finer to a coarser spatial resolution with appropriate upscaling methods. The purpose of this paper is to compare and evaluate current spatial upscaling methods using MODIS remote sensing data with multiple spatial resolutions. In the research Northeast China was selected as the study area. MODIS data with spatial resolutions of 250 m (2 bands) and 500 m (7 bands) were used as the test data. Through using the selected upscaling methods the Band 1 and Band 2 data of MODIS were scaled up from 250 m to 500 m spatial resolution. On the basis of land cover characteristics of Northeast China the MODIS data located in the study area was classified into the five land cover types including water grasslands forests farmlands and bare lands using maximum likelihood method. The land cover classification results were further compared with MODIS Land Cover Type product. Finally Structural Similarity (SSIM) was selected to evaluate the effects of these upscaling methods. The research can provide more useful information for spatial scaling transformation in remote sensing data applications. 2012 SPIE.
	Efficient human action recognition using accumulated motion image and support vector machines (EI CONFERENCE) 会议论文 OAI收割 International Workshop on Advanced Computational Intelligence and Intelligent Informatics, IWACIII 2011, November 19, 2011 - November 23, 2011, Suzhou, China 作者: Zhang X.; Zhang J.; Zhang J.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：70/0 \| 提交时间：2013/03/25 Vision-based human action recognition provides an advanced interface and research in this field of human action recognition has been actively carried out. This paper describes a scheme for recognizing human actions from a video sequences. The proposed method is an extension of the Motion History Image(MHI) method based on the ordinal measure of accumulated motion which is robust to variations of appearances. We define the accumulated motion image(AMI) using image differences firstly. Then the AMI of the video sequencesis resized to a MN regulation following the standard of training phases. Finally we employ Support Vector Machine(SVM) as a classifier to distinguish the current activity in target video sequences. In a word our proposed algorithm not only outperforms the state of art on public available KTH data set and Weizmann data set but also proves practical to some real world applications in addition this method is computationally simple and able to achieve a satisfactory accuracy.
	Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China 作者: Wang S.-R.; Lin G.-Y.; Yu L. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.
	Multi-focus image fusion algorithm based on adaptive PCNN and wavelet transform (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Wu Z.-G.; Wang M.-J.; Han G.-L. 收藏 \| 浏览/下载：82/0 \| 提交时间：2013/03/25 Being an efficient method of information fusion image fusion has been used in many fields such as machine vision medical diagnosis military applications and remote sensing.In this paper Pulse Coupled Neural Network (PCNN) is introduced in this research field for its interesting properties in image processing including segmentation target recognition et al. and a novel algorithm based on PCNN and Wavelet Transform for Multi-focus image fusion is proposed. First the two original images are decomposed by wavelet transform. Then based on the PCNN a fusion rule in the Wavelet domain is given. This algorithm uses the wavelet coefficient in each frequency domain as the linking strength so that its value can be chosen adaptively. Wavelet coefficients map to the range of image gray-scale. The output threshold function attenuates to minimum gray over time. Then all pixels of image get the ignition. So the output of PCNN in each iteration time is ignition wavelet coefficients of threshold strength in different time. At this moment the sequences of ignition of wavelet coefficients represent ignition timing of each neuron. The ignition timing of PCNN in each neuron is mapped to corresponding image gray-scale range which is a picture of ignition timing mapping. Then it can judge the targets in the neuron are obvious features or not obvious. The fusion coefficients are decided by the compare-selection operator with the firing time gradient maps and the fusion image is reconstructed by wavelet inverse transform. Furthermore by this algorithm the threshold adjusting constant is estimated by appointed iteration number. Furthermore In order to sufficient reflect order of the firing time the threshold adjusting constant is estimated by appointed iteration number. So after the iteration achieved each of the wavelet coefficient is activated. In order to verify the effectiveness of proposed rules the experiments upon Multi-focus image are done. Moreover comparative results of evaluating fusion quality are listed. The experimental results show that the method can effectively enhance the edge details and improve the spatial resolution of the image. 2011 SPIE.
	High-performance Computing in China: Research and Applications 期刊论文 OAI收割 INTERNATIONAL JOURNAL OF HIGH PERFORMANCE COMPUTING APPLICATIONS, 2010, 卷号: 24, 期号: 4, 页码: 363-409 作者: Sun, Ninghui; Kahaner, David; Chen, Debbie \| 收藏 \| 浏览/下载：16/0 \| 提交时间：2019/12/16 High performance computing research and applications China
	Experiments of second harmonic generation output in pulsed TEA CO 2 laser (EI CONFERENCE) 会议论文 OAI收割 High-Power Lasers and Applications V, October 18, 2010 - October 19, 2010, Beijing, China 作者: Li D. 收藏 \| 浏览/下载：64/0 \| 提交时间：2013/03/25 It is always the hot subject to realize the output of high-power laser in the range of 3-5m wavelength. This rang of wave band has greatly important applications in military because it located in the atmosphere window. Generally there are two ways to obtain this range of laser wavelength. One way is through optical parameter oscillation (OPO) from shorter laser wavelength and the other is through second harmonic generation (SHG) from longer laser wavelength. Firstly the comparison between tow nonlinear crystals ZnGeP2 and AgGaSe2 is conducted for their nonlinear coefficient and damaging threshold in theory. The theoretical results show that the crystal AgGaSe 2 is more suitable for the SHG of pulsed TEA CO2 laser. When using pulsed TEA CO2 laser with wavelength of 9.3m to pumping AgGaSe2 SHG crystal the wavelength of 4.65m is obtained. In the condition of repetition rate 100Hz the upmost output power of single pulse is up to level of 1W which corresponding efficiency of SHG is about 6%. The experimental results show that the polarization of laser beam has greatly influence on the SHG output of the crystal. Under the radiation of 3MW/cm 2 from fundamental wave and the right position for maximal SHG output in the crystal when polarization of laser beam rotates 4.5 the SHG output of energy decrease about 30%. The research of this paper will make a foundation for further development of mid-infrared laser. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Guo L.-H.; Guo R.-H.; Wang S.-W. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.
	Study on agricultural application of remote sensing technology in bwater and soil loss district of China's loess plateau - Taking Shanxi Province as an example 会议论文 OAI收割 Geoinformatics 2008 and Joint Conference on GIS and Built Environment: Monitoring and Assessment of Natural Resources and Environments, Guangzhou, China, 2008 Qiao; Yuliang1; 2; Sun; Taisen3; Zhao; Shangmin4 收藏 \| 浏览/下载：24/0 \| 提交时间：2011/08/23 Research and development managementControlled terms: Catchments - Decision making - Environmental protection - Geographic information systems - Information management - Monitoring - Natural resources exploration - Remote sensing - Soil conservation - Soils - Sustainable development - Technology - Agricultural applications - Dynamic monitoring - Environment managements - Environment monitoring - Fusion systems - Geographical information systems - Geographical informations - Information management systems - Loess plateaux - Long terms - Rapid development - Remote Sensing Monitoring - Remote sensing technologies - Research technologies - Science and technologies - Soil loss
	Research on long focal length On-axis TMA system for high-resolution remote sensing (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Advanced Optical Manufacturing Technologies, July 8, 2007 - July 12, 2007, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 TMA (Three Mirror Anastigmatic) is popular to the design of space-based optical system. This paper describes the characteristics of the on-axis TMA optical system. An on-axis TMA system with 13m focal length is designed and analyzed. To solve the initial configuration parameters Cassagrain structure is confirmed firstly and then the tertiary mirror. Based on initial configuration parameters automatic optimization is executed in ZEMAX program and design result with excellent image quality is acquired which shows the procedure we choosed with good advantage of computer processing. As the distortion of the design reaches 1% its influences on TDICCD brushing camera are discussed. The source of distortion is analyzed and correcting methods are considered. Zero focal power corrector is chosen to correct the distortion and the corrected distortion is less than 0.02%. The research on on-axis TMA system in this paper makes a foundation for farther high-resolution remote sensing applications.