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	Weighted integral solvers for elastic scattering by open arcs in two dimensions 期刊论文 OAI收割 INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, 2021, 页码: 18 作者: Bruno, Oscar P.; Xu, Liwei; Yin, Tao \| 收藏 \| 浏览/下载：6/0 \| 提交时间：2021/04/26 Calderó n relation elasticity open arc second‐ kind integral solver
	Measuring System with dual magnetic sensors for outer-rotor type torque motor 会议论文 OAI收割 NOV 16-17, 2013 作者: Qiao, H; Shu, Xindong; Zhou, Jie; Liao, Youyong; Zhang, Chi \| 收藏 \| 浏览/下载：26/0 \| 提交时间：2018/01/12 Dual Magnetic Sensors Outer-rotor Torque Motor Fpga Arc-second
	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：21/0 \| 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.
	A new high-precision measurement system used in the image calibration of large-sized photographic instrument (EI CONFERENCE) 会议论文 OAI收割 Optical Design and Testing II, November 8, 2004 - November 11, 2004, Beijing, United states 作者: Li Y.; Liu Z.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 The purpose of characterizing the image of large-sized photographic instrument is to make the directionality of three coordinate axises in the three-dimensional coordinate of the image and the directionality of three axises of coordinate in the frame of axes of the instrument keep the same direction. This problem was solved by a high-precision measurement system composed of double-theodolite and a set of communication system. Two cube prisms will be respectively placed on the image surface and the instrument. Every cube prism will stand for a three-dimensional coordinate from the image surface or the instrument. As a result the interdependence of both coordinates from the image surface and the instrument can be obtained by measuring the interdependence of the both cube prisms with autocollimation survey axiom. In the survey system two high-precision stations TDA5005 from Leica Company will be selected as double-theodolite and the interdependence of both coordinates can be achieved by moving the station only at one time. Therefore this measurement system is a high efficient and high-precision surveying method to the image calibration of the large-sized photographic instrument. Based on the experiment its measuring accuracy can reach arc-second level.