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Structural design of large aperture rectangular mirror for space telescope (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Civil Engineering and Transportation, ICCET 2012, October 27, 2012 - October 28, 2012, Guilin, China
作者:  
Li Z.;  Li Z.
收藏  |  浏览/下载:49/0  |  提交时间:2013/03/25
Structural design of large aperture mirror is one of the key technologies for space telescope development. To meet the requirements of high stiffness  strength and thermal dimensional stability  some factors such as support scheme  materials selection  lightweight design and flexible support design were taken into account. The three supports location of the mirror was determined according to the modal analytical solution. By adjusting the parameters of flexure hinge  influences of gravity  assembly stress and thermal stress on the mirror were reduced obviously. Finite element analysis (FEA) results indicate that the surface accuracy reach to rms10.2nm and 10.8nm under the gravity along optical axis direction and 5C uniform temperature rise respectively  the fundamental frequency of the mirror component is 268Hz. Dynamics test shows that the first order natural frequency is 256Hz  which shows an error less than 5% compared to FEA results. (2013) Trans Tech Publications  Switzerland.  
Longitudinal control law design and simulation of fixed-wing UAV (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Measurement, Instrumentation and Automation, ICMIA 2012, September 15, 2012 - September 16, 2012, Guangzhou, China
作者:  
Duan Z.
收藏  |  浏览/下载:30/0  |  提交时间:2013/03/25
STEP Mission: Search for Terrestrial Exo-Planets 会议论文  OAI收割
European Planetary Science Congress 2013,, London, UK, 2013
Chen D.; Wu; J.; Li B.
收藏  |  浏览/下载:35/0  |  提交时间:2014/04/30
Communication synchronization in wireless optical link (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Control Engineering and Communication Technology, ICCECT 2012, December 7, 2012 - December 9, 2012, Shenyang, Liaoning, China
作者:  
Guo J.;  Guo J.;  Wang H.;  Wang H.;  Wang H.
收藏  |  浏览/下载:36/0  |  提交时间:2013/03/25
An FPGA based transceiving synchronization method is demonstrated for Free Space Optical (FSO) communication system  which is discussed separately as the transmitting protocol and the receiving protocol. During the discussion of these two parts  the co-operation of them is also discussed. The transmitting protocol interfaces the outer input data with a parallel port  buffers the input data  encodes the input data stream  serializes the parallel data and outputs the serialized data. It also has an output management unit to manage the activity of each part of the transmitting protocol. The receiving protocol filters and synchronizes the input serial data stream  parallels the serial data stream  decodes the input data  checks received error  handles transmission exception and interfaces the outer receiver with a parallel port. The entire transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. The presented protocol could be taken as "protocol transparent" for outer interfaces  meaning that when interfacing the presented system to an outer system  users don't have to consider what protocol the outer system transceiving data stream is under  for example  the TCP/IP protocol or anything else  in the case that its I/O interface is a parallel port. Simulation and final experiment prove that the protocol presented is a working solution at a certain bit rate scale. 2012 IEEE.  
Analysis of zenith pass problem and tracking strategy design for roll-pitch seeker (EI CONFERENCE) 会议论文  OAI收割
作者:  
Jiang H.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Roll-pitch seeker is currently applied in particular missiles. There is a stubborn problem called zenith pass problem while roll-pitch seeker is used. Analysis of the zenith pass problem which always results in loss of target is presented in this paper. Based on the analysis result  tracking strategy is carried out to deal with zenith pass problem. To prove the validity of tracking strategy  a practical roll-pitch seeker was accomplished. Model identification and common PID controllers for the physical roll-pitch seeker are taken on  after that  both disadvantages derived from zenith pass problem in tracking process and meliorated phenomenons by the tracking strategy are shown. It is concluded that the tracking strategy designed for solving the zenith pass problem is efficient. 2011 Elsevier Masson SAS. All rights reserved.  
Classification of hyperspectral image based on SVM optimized by a new particle swarm optimization (EI CONFERENCE) 会议论文  OAI收割
2012 2nd International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2012, June 1, 2012 - June 3, 2012, Nanjing, China
作者:  
Gao X.;  Yu P.;  Yu P.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
Support Vector Machine (SVM) is used to classify hyperspectral remote sensing image in this paper. Radial Basis Function (RBF)  which is most widely used  is chosen as the kernel function of SVM. Selection of kernel function parameter is a pivotal factor which influences the performance of SVM. For this reason  Particle Swarm Optimization (PSO) is provided to get a better result. In order to improve the optimization efficiency of kernel function parameter  firstly larger steps of grid search method is used to find the appropriate rang of parameter. Since the PSO tends to be trapped into local optimal solutions  a weight and mutation particle swam optimization algorithm was proposed  in which the weight dynamically changes with a liner rule and the global best particle mutates per iteration to optimize the parameters of RBF-SVM. At last  a 220-bands hyperspectral remote sensing image of AVIRIS is taken as an experiment  which demonstrates that the method this paper proposed is an effective way to search the SVM parameters and is available in improving the performance of SVM classifiers. 2012 IEEE.  
The design problems of one kind of chaotic one-way hash function (EI CONFERENCE) 会议论文  OAI收割
2012 4th International Conference on Multimedia and Security, MINES 2012, November 2, 2012 - November 4, 2012, Nanjing, Jiangsu, China
Li P.; Zhang M.; Shi J.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
Use skill of external memory expansion for DSP of TMS320VC5409 (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
作者:  
Huang L.
收藏  |  浏览/下载:29/0  |  提交时间:2013/03/25
Image quality assessment based on gradient complex matrix (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Systems and Informatics, ICSAI 2012, May 19, 2012 - May 20, 2012, Yantai, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
Spanwise stretching and collapse motions stabilize leading-edge vortex in slow-flying bats 会议论文  OAI收割
23rd International Congress of Theoretical and Applied Mechanics, 中国北京/Beijing, China, 2012-08-19
作者:  
Wang SZ(王士召);  He GW(何国威);  Zhang X(张星)
收藏  |  浏览/下载:26/0  |  提交时间:2014/04/02