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浏览/检索结果: 共3条，第1-3条 帮助 已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Image enhancement for outdoor long-range surveillance using IQ-learning multiscale Retinex 期刊论文 IET IMAGE PROCESSING, 2017, 卷号: 11, 期号: 9, 页码: 786-795 作者:  Liu, Haoting;  Lu, Hanqing;  Zhang, Yu 收藏  |  浏览/下载：41/0  |  提交时间：2018/03/03 Image Enhancement  Video Surveillance  Image Restoration  Wavelet Transforms  Neural Nets  Backpropagation  Outdoor Long-range Surveillance  Blind Iq-learning Multiscale Retinex  Visible Light Camera-based  Image Enhancement Method  Blind Image Quality Learning Multiscale Retinex  Image Brightness Degree  Image Region Contrast Degree  Image Edge Blur Degree  Image Colour Quality Degree  Image Noise Degree  Wavelet Transform Multiscale Retinex  Wt_msr  Multiple Optimal Control Parameter  Mocp  Backpropagation Neural Network  Bpnn   Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China Zhang X.; Jiang Z.; Wei Q.; Jia H. 收藏  |  浏览/下载：30/0  |  提交时间：2013/03/25 A concentric glass spherical dome was usually chosen as the transparent window mounted in front of the optical lens in an image seeker. However  optical ray had to change its direction when propagating through the dome due to refraction unless passing through the center of the dome  which demanded gimbal point coincide with the center of the dome exactly. In fact  gimbal point displacement could not be eliminating due to fabrication  assembly and vibration  therefore the optical axis pointing error generated. In this paper  the effect of gimbal point displacement on optical axis pointing precision in an image seeker was analyzed  and the theoretical expression of the optical axis pointing error was derived based on geometric optics  and the error dynamics was explored by numerical. Take a visible light image seeker as a case  the thickness of concentric glass spherical dome was 8mm and the inner radius was 72mm  and the optical axis pointing errors varying dynamically with the look angle and the gimbal point displacement were shown in graph. When the gimbal displacement was 0.11mm  the maximum optical axis pointing error was 0.054mrad that is equal to the instantaneous field of view (IFOV) corresponding to the camera system whose focal length was 120mm and pixel size was 6.5m. Furthermore  with the gimbal displacement increasing  the optical axis pointing error increased linearly. The analyzed results provided a theoretical basis for the displacement range  which had to be limited strictly in the gimbal design process. 2011 IEEE.   Gimbal displacement error analysis on an electro-optical seeker (EI CONFERENCE) 会议论文 Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China Jiang Z.; Zhang X.; Ai X.; Wei Q.; Jia H. 收藏  |  浏览/下载：23/0  |  提交时间：2013/03/25 It is essential to analyze the gimbal displacement errors for a seeker due to the importance for cueing of targets and tracking for the final approach. Otherwise  for a seeker electro-driven with a concentric glass dome  the large errors will decrease the picking  pointing  and tracking precision rooted from the displacement errors existing between the rotation center of the optical system and the gimbal. And the gimbaled camera system displacement errors are never eliminated but reduced due to the geometric errors consists of geometric tolerances of gimbal structure  manufacture  installation and vibration coming from working environment. In this paper  the gimbal displacement errors in an electro-optically stabilized platform resulting from geometric errors and environment errors were analyzed and shown in detail. The mathematical modal of the gimbal displacement errors created based on multi-body dynamics demonstrated the connection between the gimbal displacement errors and the stabilized platform. Taking a visible light image seeker as a case  the diameter is 120mm  and the geometric tolerances came from the values of primary design and the vibration data came from the environmental vibration test on the pitch-yaw seeker  and at the same time  the errors resulting from installation were considered too. Based on calculating  the maximum gimbal displacement error will reach to 0.2mm for pitching angle smaller than 40 and yawing angle smaller than 60. However  the critical parts have been found out according to the probability theory and the reliability analysis successfully used in the paper  and finally  the maximum gimbal displacement error reduced to 0.1mm  which is acceptable corresponding to the picking  pointing and tracking precision for an optical imaging seeker. 2010 Copyright SPIE - The International Society for Optical Engineering.