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	Surface and Edge Detection for Primitive Fitting of Point Clouds 会议论文 OAI收割 Los Angeles CA USA, 2023-8-6至2023-8-10 作者: Li, Yuanqi; Liu, Shun; Yang, Xinran; Guo, Jianwei; Guo, Jie \| 收藏 \| 浏览/下载：19/0 \| 提交时间：2024/06/03 Primitive fitting point cloud shape reconstruction deep neural network
	Research on mirror surface shape of space camera fitting based on SVD 会议论文 OAI收割 Beijing, China, 2019-07-07 作者: Huang, Tuo; Chen, Rong-Li; Chu, Chang-Bo \| 收藏 \| 浏览/下载：10/0 \| 提交时间：2020/03/04 mirror surface shape Zernike polynomials spherical mirror fitting precision Zernike polynomials terms singular value decomposition
	Head-Raising of Snake Robots Based on a Predefined Spiral Curve Method 期刊论文 OAI收割 APPLIED SCIENCES-BASEL, 2018, 卷号: 8, 期号: 11, 页码: 1-20 作者: Zhang XB(张晓波); Liu JG(刘金国); Yang, Chenguang \| 收藏 \| 浏览/下载：27/0 \| 提交时间：2018/12/16 snake robots head-raising shape-fitting phase-shifting spiral curve
	Adaptive Wiener filtering with Gaussian fitted point spread function in image restoration (EI CONFERENCE) 会议论文 OAI收割 2011 IEEE 2nd International Conference on Software Engineering and Service Science, ICSESS 2011, July 15, 2011 - July 17, 2011, Beijing, China 作者: Yang L.; Zhang X.; Zhang X.; Zhang X.; Yang L. 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/03/25 In the imaging process of the space remote sensing camera there was degradation phenomenon in the acquired images. In order to reduce the image blur caused by the degradation the remote sensing images were restored to give prominence to the characteristic objects in the images. First the frequency-domain notch filter was adopted to remove strip noises in the images. Then using the ground characters with the knife-edge shape in the images the point spread function of the imaging system was estimated. In order to improve the accuracy the estimated point spread function was corrected with Gaussian fitting method. Finally the images were restored using the adaptive Wiener filtering with the fitted point spread function. Experimental results of the real remote sensing images showed that almost all strip noises in the images were eliminated. After the denoised images were restored its variance and its gray mean gradient increased also its laplacian gradient increased. Restoration with Gaussian fitted point spread function is beneficial to interpreting and analyzing the remote sensing images. After restoration the blur phenomenon of the images is reduced. The characters are highlighted and the visual effect of the images is clearer. 2011 IEEE.
	Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China 作者: Zhang P. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror the surface configuration must be tested. However membrane mirror's shape is always changed by variable voltages on the electrodes and the optical properties of membrane materials using in our experiment are poor so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source CCD camera splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Configuring an electrostatic membrane reflector with potentials exerted on distributed electrodes (EI CONFERENCE) 会议论文 OAI收割 2009 IEEE International Conference on Mechatronics and Automation, ICMA 2009, August 9, 2009 - August 12, 2009, Changchun, China 作者: Zhang P.; Shi G. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 Electrostatic membrane reflector (EMR) is very promised for optical quality application with the merits of utra-lightweight and flexible. Configuring a circular membrane reflector with electrostatic potentials exerted on distributed electrodes can approximatively produce a parabolic shape. A 300mm EMR (made from polyimide) stretched by distributed electrodes below is designed and the number of concentric electrodes needed for membrane shape forming is analysed. First based on an analytical solution of Poisson's equation determine the membrane control matrix by finding influence functions of 3 concentric electrodes and 6 control points on membrane surface in order to compute the needed voltages exerted on the distributed electrodes by the method of least-squares fitting. Then the final shape solved by finite element analysis with ANSYS is contrasted with the paraboloid and deviates greatly when the central displacement of membrane is beyond 2.5mm but in this range increasing the number of electrodes and control points will get a better shape. The corresponding errors are analyzed and the control method is concluded. Only using the integrated method of analytical computation numerical analysis and experiment the membrane shape of certain central displacement can be exactly predicted and controlled. 2009 IEEE.
	The application of Doppler broadening and Doppler shift to spectral analysis 期刊论文 OAI收割 SPECTROSCOPY AND SPECTRAL ANALYSIS, 2002, 卷号: 22 - \| 收藏 \| 浏览/下载：8/0 \| 提交时间：2020/10/26 PLASMA the distribution of line shape Gaussian fitting Doppler broadening Doppler shift