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	Hapke's parameters inverse method of Lunar analog sample 期刊论文 OAI收割 JOURNAL OF INFRARED AND MILLIMETER WAVES, 2018, 卷号: 37, 期号: 2, 页码: 227-+ 作者: Xu Xue-Sen; Liu Jian-Jun; Liu Bin; Liu Da-Wei \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2020/03/10 bi-directional reflectance Chang' E-3 VIS-NIR Imaging Spectrometers reflectance photometric correction Hapke model radiation transfer the least squares algorithm
	A sub-pixel extraction method for the center of the circular structure from spot array calibration target (EI CONFERENCE) 会议论文 OAI收割 2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China 作者: Liu Y.; Zhang T.; Yang H.; Gao X.; Liu Y. 收藏 \| 浏览/下载：75/0 \| 提交时间：2013/03/25 The imaging measurement system must be calibrated before application. In calibration procedure sub-pixel center extraction is the crucial step for the final accuracy. In this paper a new sub-pixel extraction method is proposed. Edge detection at pixel level is obtained using LOG operator then sub-pixel edge detection is realized using the Facet model. Finally the least squares ellipse fitting is operated on the sub-pixel edge to determine the sub-pixel center. Experiment on a series of simulated images indicates that this algorithm is able to realize the center location accuracy of 0.01-0.02 pixel and meets the requirement of sub-pixel level. (2012) Trans Tech Publications Switzerland.
	Image registration based on Mexican-hat wavelets and pseudo-Zernike moments (EI CONFERENCE) 会议论文 OAI收割 2012 World Automation Congress, WAC 2012, June 24, 2012 - June 28, 2012, Puerto Vallarta, Mexico 作者: Liu Y.; Liu Y.; Liu Y. 收藏 \| 浏览/下载：36/0 \| 提交时间：2013/03/25 Image registration is a key technique in pattern recognition and image processing and it is widely used in many application areas such as computer vision remote sensing image fusion and object tracking. A method for image registration combining Mexican-hat wavelets and pseudo-Zernike moments is proposed. Firstly feature points are extracted using scale-interaction Mexican-hat wavelets in the reference image and sensed image respectively. Then pseudo-Zernike moments are used to match them and classical RANSAC used to eliminate the wrong matches. And then the well match points are used to estimate the best affine transform parameters by least squares minimization. At last the sensed image is transformed and resampled to accomplish the image registration. The experiments indicate that the proposed algorithm extracts feature points and matches them exactly and eliminates wrong matched points effectively and achieves nice registration results. 2012 TSI Press.
	Gray level correction algorithm of LED display panel based on least squares approximation (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China 作者: Sun Z.-Y. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Aiming at the problem that the linear characteristic of LED display panel is not compatible with the non-linear characteristic of image data this leads to appear the large deviation during grayscale rendition the gray level correction algorithm based on least squares approximation is provided. First the necessity of gray level correction is analyzed. Then the gray level correction algorithm model is constructed according to the principle of latest squares approximation. Next realization steps are described in accordance with this constructed algorithm model. Finally this algorithm is implemented in a LED display panel whose resolution is 128128. Experimental results show that this algorithm is able to reduce the deviation obviously during grayscale rendition and the problem of gray level deformation can be resolved perfectly because the linear relation between image data after correcting and gray level is good which satisfies the linear characteristic of LED display panel. 2010 IEEE.
	Test of an off-axis asphere by subaperture stitching interferometry (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Zheng L.-G.; Zhang X.-J.; Zhang Z.-Y.; Zhang Z.-Y.; Deng W.-J. 收藏 \| 浏览/下载：52/0 \| 提交时间：2013/03/25 A new method combined subaperture stitching with interferometry(SSI) is introduced. It can test large and off-axis aspheric surfaces without the aid of other null optics. In this paper the basic principle and theory of the technique are analyzed. The synthetical optimization stitching model and effective stitching algorithm are established based on homogeneous coordinates transformation and simultaneous least-squares method. The software of SSI is devised and the prototype for testing of large aspheres by SSI is designed and developed. An off-axis asphere with the aperture of 376mm188mm is tested by this method. For comparison and validation and the difference of PV and RMS error between them is 0.047 e and 0.006 e the asphere is also tested by null compensation.The synthesized surface profile is consistent to that ofthe entire surface from null test respectively. So it provides another quantitative measurement for testing large aspheric surfaces and off-axis aspheres besides null-compensation. 2009 SPIE.
	Annular sub-aperture stitching interferometry for testing of large asphreical surfaces (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging, ISPDI 2007: Optoelectronic System Design, Manufacturing, and Testings, September 9, 2007 - September 12, 2007, Beijing, China 作者: Zheng L.-G.; Zhang X.-J.; Deng W.-J.; Wang X.-K. 收藏 \| 浏览/下载：76/0 \| 提交时间：2013/03/25 Annular subaperture stitching interferometric technology can test large-aperture and the PV and RMS of residual error of the full aperture phase distribution is 0.027 and 0.0023 high numerical aperture aspheric surfaces with high resolution the relative error of PV and RMS is -0.53% and -0.31% respectively. The results conclude that this splicing model and algorithm are accurate and feasible. So it provides another quantitive measurement for test aspheric surfaces especially for large aperture aspheres besides null-compensation. low cost and high efficiency without auxiliary null optics. In this paper the basic principle and theory of the stitching method are introduced the reasonable mathematical model and effective splicing algorithm are established based on simultaneous least-squares method and Zernike polynomial fitting. The translation errors are eliminated from each subaperture through the synthetical optimization stitching mode it keeps the error from transmitting and accumulating. The numerical simulations have been carried on by this method. As results the surface map of the full aperture after stitching is consistent to the input surface map the difference of PV error and RMS error between them is -0.0074 and -0.00052 ( is 632.8nm) respectively
	Research on tracking approach to low-flying weak small target near the sea (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Xue X.-C. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 Automatic target detection is very difficult in complicate background of sea and sky because of the clutter caused by waves and clouds nearby the sea-level line. In this paper in view of the low-flying target near the sea is always above the sea-level line we can first locate the sea-level line and neglect the image data beneath the sea-level line. Thus the noise under the sea-level line can be suppressed and the executive time of target segmentation is also much reduced. A new method is proposed which first uses neighborhood averaging method to suppress background and enhance targets so as to increase SNR and then uses the multi-point multi-layer vertical Sobel operator combined with linear least squares fitting to locate the sea-level line lastly uses the centroid tracking algorithm to detect and track the target. In the experiment high frame rate and high-resolution digital CCD camera and high performance DSP are applied. Experimental results show that this method can efficiently locate the sea-level line on various conditions of lower contrast and eliminate the negative impact of the clutter caused by waves and clouds and capture and track target real-timely and accurately.