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	A characteristic space-time conservation element and solution element method for conservation laws 期刊论文 OAI收割 JOURNAL OF COMPUTATIONAL PHYSICS, 2015, 卷号: 288, 页码: 101-118 作者: Shen H; Wen CY 收藏 \| 浏览/下载：32/0 \| 提交时间：2015/04/28 Space-time conservation element and solution element (CE/SE) method Upwind scheme Characteristic-based scheme Riemann solver
	Research on satellite platform vibration compensation technology for space optical communication (EI CONFERENCE) 会议论文 OAI收割 2012 International Meeting on Opto-Electronics Engineering and Materials Research, OEMR 2012, July 27, 2012 - July 29, 2012, Shenyang, Liaoning, China Han C.; Li X. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 The piezo-electric steering control system is used to compensate the vibration of satellite platform. The mathematical model of piezo-electric steering system is built. The adaptive controller based on improved LMS filter algorithm is designed according to this system characteristic. The adaptive delay filter is designed to solve slow convergence speed problem of traditional algorithm. Meanwhile the adaptive delay filter can also compensate phase delay of control circuit. The adaptive deviation filter is introduced and it effectively compensates the vibration deviation which is low frequency and high amplitude. The experimental results show that the remained errors are rad which meets space optical communication requirement and proves that this control scheme is valid and feasible. (2012) Trans Tech Publications Switzerland.
	Research on the identification for a nonlinear system (EI CONFERENCE) 会议论文 OAI收割 International Conference on Optical, Electronic Materials and Applications 2011, OEMA 2011, March 4, 2011 - March 6, 2011, Chongqing, China 作者: Liu J.; Jia P.; Liu J.; Liu J. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 The characteristic of the drift error of inertial platform is a high-order nonlinear dynamic system using the neural networks' abilities of universal approximation of differentiable trajectory and capturing system dynamic information this paper presents the drift error identifying project of inertial platform based on Elman networks structure. First the drift error model of inertial platform is established after selecting the input and output for network momentum and alterable speed algorithm is used to speed up the network convergence. On the basis of the algorithm the extended nonlinear node function in the hidden network does not only improve the learning speed of network but also satisfies the need of accuracy on system identification. Through the drift error data measured on inertial platform the training result shows that the scheme achieves satisfied identification results. (2011) Trans Tech Publications.
	Study of microsphere plate photomultiplier tube (EI CONFERENCE) 会议论文 OAI收割 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang X.; Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：32/0 \| 提交时间：2013/03/25 The photomultiplier tube (PMT) that can work in different wavelength is an important detector device in remote sense technology. Microsphere plate using glass beads 50to 70m in diameter sintered together is the core component of the microsphere plate photomultiplier tube It is a novel two-dimension electron multiplier. The electrons gain for a single plate is about 1017 and do not have the phenomenon of ion-feedback. Furthermore the fabrication process is very easy. In this paper much interest was put on the microsphere plate photomultiplier tube. Based on the analyses from the theory and the experiment result we point out the key technology for fabricating PMT is how to obtain glass beads with narrow range in diameter and how to sinter the glass beads with a sufficient pylome. Factors affect the gradating technology and sintering process along with the solution to them is presented. In the last the structure scheme and technological characteristic for fabricating microsphere plate photomultiplier tube were given. The pulse rising-time of MSP-PMT is below 400ps suitable to the detection of high-speed pulse. As easy to be fabricated and has great advantage over MCP multiplier in the ratio of performance to price the microsphere plate photomultiplier tube is a promising dim-light detector.
	Theoretical analysis of 980nm high power Vertical External-cavity Surface-emitting Semiconductor Laser (VECSEL) (EI CONFERENCE) 会议论文 OAI收割 ICO20: Lasers and Laser Technologies, August 21, 2005 - August 26, 2005, Changchun, China 作者: Wang L.-J.; Wang L.-J.; Ning Y.-Q.; Qin L. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 By using bottom-emitting structure we will develop laser diode (LD) pumped 980 nm VECSEL with active region of InGaAs/GaAsP/AlGaAs system. Because the thickness of barrier layer and absorption layer exceed that of quantum well single well approximation model (KP method) can be used to calculate the band structure of VECSEL. The Schrodinger equation of finite deep potential well can be adopted to calculate the energy level structures of electron heavy and light holes. According to the transition selection rule we theoretically obtained the emitting wavelength of VECSEL and calculated quasi-Femi energy of valence band and conduction band based on the analysis of energy level structure of electron and holes. By analyzing the gain of strained quantum wells we calculated the gain of VECSEL using transition matrix elements of electron heavy and light holes. We give out the threshold gain output power and other characteristic parameters. We will study the configuration of VECSEL and pumping scheme. We designed external cavity mirror active region and bottom-emitting structure. A LD-pumped vertical external cavity surface-emitting laser whose output power is greater than 1.0 W can be predicted.