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	High accuracy star image locating and imaging calibration for star sensor technology (EI CONFERENCE) 会议论文 OAI收割 6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China 作者: Wang Y.; Wang Y.; Wang Y.; Wang Y.; Wang Y. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Today aircraft attitude measurement technology plays an important role in an aircraft system because it can provide orientation for aircraft in action. Lately star sensor technology used in aircraft attitude measurement has become more and more popular because of its high accuracy light weight without attitude accumulation errors and other advantages. There are three main steps for star sensor to measure aircraft attitude star image locating star identification and attitude tracking. The latter two steps are based on the accuracy of star image locating. So it's critical to make efforts to advance the accuracy of star image locating. Some imaging errors such as spherical aberration or coma aberration also have negative effect on the accuracy of star image locating of which the effect is necessarily reduced as well. At the beginning of this article the structure of star sensor hardware is introduced. Secondly three methods for star image locating are described specifically which are traditional centroid method Gauss quadric fitting method and improved Gauss quadric fitting method. Subsequently an imaging calibration method is described for the purpose of reducing the effect of imaging errors. Finally the experiment shows that the accuracy of the star sensor is 2-arc-second. 2010 SPIE.
	Aerial image blurring caused by image motion and its restoration using wavelet transform (EI CONFERENCE) 会议论文 OAI收割 Electronic Imaging and Multimedia Technology IV, November 8, 2004 - November 11, 2004, Beijing, China 作者: Liu G. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 A wavelet-based approach of aerial blurred image restoration is proposed in this article. Image motion is inevitable in photographing for aerospace camera. Though some Image Motion Compensation(IMC) schemes are applied in aerial imaging system the ultimate image will be blurred in certain extent for the existence of IMC residual error while the forward image motion is the key element among all image motions which lead to image blurring. First the course of blurring caused by forward image motion is expressed using wavelet transform and a multiresolution sparse matrix representation of the degeneration model is obtained according to the wavelet transform. Subsequently a regularizing restoration algorithm is deduced from it and which can smoothly restraint the processed result efficiently. In the end the proposed approach is tested in MATLAB. The blurred image is restored using above-mentioned wavelet algorithm conventional contrary filter and Wiener filter algorithm separately. The conclusion that the wavelet-based restoration algorithm is superior to other two approaches is obtained by comparing the restored image's value of mean gradient. The calculating quantity of the wavelet-based blurred image restoration approach isn't large and it has good practicability in the field of image interpretation and aerial survey or drawing.
	THE QUANTUM ELECTRODYNAMICS IN A CONSTANT MAGNETIC FIELD——Ⅰ. RESEARCHING ONCE MORE THE DIRAC EQUATION SOLUTIONS OF ELECTRON IN A CONSTANT MAGNETIC FIELD 期刊论文 OAI收割 A Monthly Journal of Science, 1984, 期号: 7, 页码: 873-876 作者: Song Y(宋燠) 收藏 \| 浏览/下载：11/0 \| 提交时间：2015/12/21 coordinates Dirac rotation cylindrical vertex Probability Feynman picture 干摆 subsequently