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	Design of semi-physical simulation for small satellite by virtual display (EI CONFERENCE) 会议论文 OAI收割 2011 3rd International Conference on Mechanical and Electronics Engineering, ICMEE 2011, September 23, 2011 - September 25, 2011, Hefei, China Xu K.; Lv Y.; Jin G. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 Semi-physical simulation of attitude control system is the more synthetically test and verify for designing of small satellite control system. It is an important means of small satellite development. However the results of current semi-physical simulation system have a lot of non-intuitive. Compare with the actual environment the simulation environment still has striking disparity. So the shortcomings affect precision of simulation. Based on the virtual display technology the group semi-physical simulation system has been constructed for attitude control of small satellite due to the combination with xPC real-time environment the simulation computer high-precision single-axis air-bearing turntable reaction wheel air thrust device fiber gyroscopes sensors synchronizer power subsystem and wireless devices virtual display computer etc. Semi-physical simulation achieved the visual simulation in orbit and tracked new information of virtual environment of space into real-time simulation computer. Simulation results show that the simulation system for real-time attitude and orbit position of small satellite semi-physical simulation has an excellent display effect. At the same time Real-time transfuse of orbit information provides a more accurate space environment simulation. The simulation system of small satellite attitude control to design and evaluate the more direct and convenient. (2012) Trans Tech Publications Switzerland.
	The reason of Hopf's and Oleinik's proofs for countability of shocks being wrong 期刊论文 OAI收割 SCIENCE CHINA-MATHEMATICS, 2012, 卷号: 55, 期号: 4, 页码: 727-729 作者: Li BangHe \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2021/01/14 ORIGINAL POINTS REAL AXIS WAVES countability of shocks uncountability of shocks conservation law
	Almost all points on the real axis can be original points of shock waves 期刊论文 OAI收割 SCIENCE CHINA-MATHEMATICS, 2011, 卷号: 54, 期号: 1, 页码: 1-8 作者: Li Bang-He \| 收藏 \| 浏览/下载：14/0 \| 提交时间：2018/07/30 conservation law shock wave original points on real axis
	Study on bandwidth mutual-benefit between the azimuth and pitch in an optoelectronic tracking system (EI CONFERENCE) 会议论文 OAI收割 MEMS/MOEMS Technologies and Applications III, November 12, 2007 - November 14, 2007, Beijing, China 作者: Guo J.; Guo J.; Chen J. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 Two-axis optoelectronic tracking equipments generally use such mode that azimuth and pitch system are independently controlled. It leads to the two structures completely uncoupled therefore and reduces the state space dimension. But the main problem is that the rotational inertia of azimuth is much larger than that of pitch it is an effective control mode to the two-axis photoelectric tracking equipments. which leads its dynamic tracking performance is worse. So to find a more suitable mechanics and more effective control strategy is necessary. Considering the tracking ability this paper designs BMC (bandwidth mutual compensation) to uniformly correct the error of both the azimuth and pitch system in real time it is realized by cross coupling control to the azimuth and pitch. The simulation result verified that compared with classical uncoupling system BMS not only guarantees the state space dimension but improves systematic tracking performance about 2
	基于同步移相技术的1/4波片快轴方位角的实时测量期刊论文 OAI收割 Chin. Opt. Lett., 2008, 卷号: 6, 期号: 8, 页码: 568, 571 杨坤; 曾爱军; 王向朝; 王华; 唐锋收藏 \| 浏览/下载：1204/147 \| 提交时间：2009/09/18 偏振 Fast-axis angle 1/4波片 Quarter-wave plate 快轴方位角 Real-time measurements 同步移相
	Automatic spin coater for concave spherical substrate (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, July 8, 2007 - July 12, 2007, Chengdu, China Fengchao L.; Jingsong G.; Xiaoguo F.; Jingli Z.; Zhijun X.; Jun H.; Fenglin X.; Huiqing W.; Xiaohan L. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Coating photoresist film with uniform thickness on concave spherical substrate (CSS) is very important for microfabrication of concave spherical optical elements by lithography technique via a laser direct writer for the uneven photoresist film will result in ununiformity of line width so as to influence the characters of optical elements. For improving the uniformity of photoresist film coating on CSS an automatic spin coater was designed. The process and the mathematical model of spin coating for CSS were analyzed. Difficulties for realizing the spin coater consist of the control of multi-axis motion precisely and collaboratively valves on/ff properly and real-timely. A flexible and well-behaved spinning motion system was achieved by tmeans of principal and subordinate CPUs control. The motion program for spin coating could be created and implemented automatically while the pressure and the valves were was watched and controlled in real time. Film coating and laser direct writing experiments on a CSS with aperture equals to 100 mm and radius equals to 370 mm were performed. Photoresist film with uniform thickness on CSS was obtained by selecting proper spin coating parameters such as rotational speed acceleration and viscosity of the photoresist. After development the section analysis by the atomic force microscope showed that photoresist film thickness was about 517 nm in the center and about 520 nm in the edge of substrate the film thickness error was within 1% and the line width was about 6.0 m with steep sides parallel each other. Experimental results indicate that uniform thickness of thin photoresist film has been coated on CSS by the spin coater which contributes to quality improvement of laser direct writing lines on CSS.
	Research and development on the valve-less piezoelectric pump with unsymmetrical corrugation chamber bottom (EI CONFERENCE) 会议论文 OAI收割 2006 IEEE International Conference on Information Acquisition, ICIA 2006, August 20, 2006 - August 23, 2006, Weihai, Shandong, China 作者: Zhang J.; Li D.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 The valve-less piezoelectric pump is more suitable for minimization and microminiaturization than the valve piezoelectric pump especially for the Microelectromechanical System (MEMS) because of its simple structure. However in order to control the flow direction of the fluid through the pump some assembles have to be attached outside the chamber. And it is no doubt that these assembles will take some space and hinder its further microminiaturization. In this paper a novel valve-less piezoelectric pump with unsymmetrical corrugation chamber bottom (UCCB) is presented. It ingeniously takes advantage of the space of the chamber by developing its bottom into a unsymmetrical corrugation shape along the axis of the inlet and outlet. As a result a series of diffuse pipes and nozzle pipes (or wedge-shaped pipes) which substitute the regular diffuse/nozzle elements fitted outside the chamber are alternatively formed between the unsymmetrical corrugation chamber bottom (UCCB) and the piezoelectric vibrator. The piezoelectric vibrator is opposite to the UCCB. And these diffuse pipes and nozzle pipes are able to force the fluid in the chamber to flow along a single direction when the pump works. And then the mathematic model is established to present the relationship between the mean energy loss and the flow rate of the pump. Basing on the mathematic model the theory on the pump working is analysed. Finally a real UCCB valve-less piezoelectric pump is manufactured and the test with it is carried out to verify the theory above-mentioned. 2006 IEEE.