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	Numerical bounds on the Crouzeix ratio for a class of matrices 期刊论文 OAI收割 CALCOLO, 2024, 卷号: 61, 期号: 2, 页码: 18 作者: Crouzeix, Michel; Greenbaum, Anne; Li, Kenan \| 收藏 \| 浏览/下载：18/0 \| 提交时间：2024/07/22 Numerical range Spectral set
	A Real-Time Regional Forecasting System Established for the South China Sea and Its Performance in the Track Forecasts of Tropical Cyclones during 2011-13 期刊论文 OAI收割 WEATHER AND FORECASTING, 2015, 卷号: 30, 期号: 2, 页码: 471-485 作者: Peng, Shiqiu; Li, Yineng; Gu, Xiangqian; Chen, Shumin; Wang, Dongxiao 收藏 \| 浏览/下载：74/0 \| 提交时间：2016/11/02 Tropical cyclones Numerical weather prediction forecasting Operational forecasting Short-range prediction Regional models
	A Real-Time Regional Forecasting System Established for the South China Sea and Its Performance in the Track Forecasts of Tropical Cyclones during 2011-13 期刊论文 OAI收割 WEATHER AND FORECASTING, 2015, 卷号: 30, 期号: 2, 页码: 471-485 作者: Peng, Shiqiu; Li, Yineng; Gu, Xiangqian; Chen, Shumin; Wang, Dongxiao 收藏 \| 浏览/下载：46/0 \| 提交时间：2016/11/02 Tropical cyclones Numerical weather prediction forecasting Operational forecasting Short-range prediction Regional models
	Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China 作者: Zhang X.; Zhang X.; Zhang X. 收藏 \| 浏览/下载：39/0 \| 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.
	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.
	Northeast Asian dust storms: Real-time numerical prediction and validation SCI/SSCI论文 OAI收割 2003 Shao Y. P.; Yang Y.; Wang J. J.; Song Z. X.; Leslie L. M.; Dong C. H.; Zhang Z. H.; Lin Z. H.; Kanai Y.; Yabuki S.; Chun Y. S. 收藏 \| 浏览/下载：33/0 \| 提交时间：2012/06/08 dust storm aerosol numerical prediction erosion modeling system long-range transport wind erosion yellow sand april 1998 size distributions saharan dust east-asia emission cycle