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Learning and Controlling Multiscale Dynamics in Spiking Neural Networks Using Recursive Least Square Modifications 期刊论文  OAI收割
IEEE TRANSACTIONS ON CYBERNETICS, 2024, 页码: 14
作者:  
Wei, Qinglai;  Han, Liyuan;  Zhang, Tielin
  |  收藏  |  浏览/下载:40/0  |  提交时间:2024/03/27
LABTM control system based on FPGA (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Mechatronics and Applied Mechanics, ICMAM 2012, December 8, 2012 - December 9, 2012, Taiwan
作者:  
Wang Y.;  Yu P.;  Yu P.
收藏  |  浏览/下载:153/0  |  提交时间:2013/03/25
This paper presents the digital PI control method for design and simulation of a high precision limited angle brushless torque motor control system in Field Programmable Gate Array device (FPGA). The direct drive structures which are widely applied in many servo control fields. Matlab Xilinx System GeneratorR toolbox based on Fixed-Point Arithmetic is used to design the digital PI controller using DSP architecture  plot the responses of the control system and generate the VHDL source code. The control system model consists of a digital PI  a real LABTM  and a real absolute Inductosyn  encoder to rpm and position blocks. Through loading generated codes in process of the simulation that built by the digital discrete model  it is verified that the rising time of current loop is only 1.2ms  and rate loop is 8ms  overshoot is rarely 4.2%. Finally  the comprehensive positioning accuracy of system can reach up to 5 arc sec  and the rate jitter achieves 5% with the 4 arc sec accuracy absolute Inductosyn. (2013) Trans Tech Publications  Switzerland.  
Data normalization of single camera visual measurement network system (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Information Technology and Management Innovation, ICITMI 2012, November 10, 2012 - November 11, 2012, Guangzhou, China
作者:  
Zhang Y.-C.;  Zhou J.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
With the development of visual measurement system  Normalize the measured coordinates into the same world coordinate system  Apply in the three coordinate measuring machine(CMM) to have the simulation experiment  So the data normalization has the advantage of more high precision. (2013) Trans Tech Publications  the visual measurement system of single camera which applied in the imaging theory of optical feature points  then get the global data  the result indicates that the maximum absolute tolerance between the normalization coordinates via the center of point set and the ones measured by CMM directly is 0.058mm  Switzerland.  it has been widespread used in the modern production. Due to the limit of the environment in scene  and achieve the overall measurement  the visual measurement system of single camera could not measure the shield between the measured objects each other. Focus on this problem  But the one between the coordinate repeatedly measured at the position of one network control point is 0.066mm  present a kind of the the knowledge of measurement network based on the visual measurement of single camera  set up the measurement network system via the multi-control points. Measure the optical feature points in every network control point via the visual measurement system of single camera  
Space optical remote sensor of the CAE thermal control index calculation method (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China
作者:  
Li L.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
The thermal control indicators CAE methods of Space optical remote sensor are analyzed in the presented work. We sat up a thermal optical analysis model for space optical remote sensor. By assuming fully covered by in-orbit temperature load  and using the finite element method for thermal deformation analysis  we obtained the optical remote sensor surface deformation and displacement under various thermal loading. Using ZERNIKE polynomial  wave was fitted to obtain ZERNIKE polynomial coefficients which were incorporated into the optical system design. Using CODE V optical calculation software  heat-ray machines under elastic deformation of the system point spread function  transfer function (MTF)  wave front differential (WFE) etc. were calculated. Image quality changes of remote sensors are discussed in variety assumed cases such as temperature loads of quality change. By repeated iteration  critical value of temperature fields meeting the design requirements are obtained for the optical system. Optical indicators were converged to the temperature field indicator  then reasonable indicators of thermal control for remote sensors were obtained. For the thermal control design  this method provided a reliable basis for design. (2011) Trans Tech Publications  Switzerland.  
Imaging control of airborne area CCD mapping camera (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
作者:  
Chen X.;  Chen X.;  Chen X.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
Research on automatic Hartmann test of membrane mirror (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, April 26, 2010 - April 29, 2010, Dalian, China
作者:  
Zhang P.
收藏  |  浏览/下载:31/0  |  提交时间:2013/03/25
Electrostatic membrane mirror is ultra-lightweight and easy to acquire a large diameter comparing with traditional optical elements  so its development and usage is the trend of future large mirrors. In order to research the control method of the static stretching membrane mirror  the surface configuration must be tested. However  membrane mirror's shape is always changed by variable voltages on the electrodes  and the optical properties of membrane materials using in our experiment are poor  so it is difficult to test membrane mirror by interferometer and null compensator method. To solve this problem  an automatic optical test procedure for membrane mirror is designed based on Hartmann screen method. The optical path includes point light source  CCD camera  splitter and diffuse transmittance screen. The spots' positions on the diffuse transmittance screen are pictured by CCD camera connected with computer  and image segmentation and centroid solving is auto processed. The CCD camera's lens distortion is measured  and fixing coefficients are given to eliminate the spots' positions recording error caused by lens distortion. To process the low sampling Hartmann test results  Zernike polynomial fitting method is applied to smooth the wave front. So low frequency error of the membrane mirror can be measured then. Errors affecting the test accuracy are also analyzed in this paper. The method proposed in this paper provides a reference for surface shape detection in membrane mirror research. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Design of ground-based physical simulation system for satellite-borne TDI-CCD dynamic imaging (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Zhang L.;  Zhang L.;  Sun Z.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
As we know  the existence of image motion has a bad effect on the image quality of satellite-borne TDI CCD camera. Although many theories on image motion are proposed to cope with this problem  few simulations are done to justify the proposed theories on ground. And thus  in this paper  a ground-based physical simulation system for TDI CCD imaging is developed and specified  which consists of a physical simulation subsystem for precise satellite attitude control based on a 3-axis air bearing table  and an imaging and simulation subsystem utilizing area-array CCD to simulate TDI CCD. The designed system could realize not only a precise simulation of satellite attitude control  whose point accuracy is above 0.1 and steady accuracy above 0.01/s  but also an imaging simulation of 16-stage TDI CCD with 0.1s its integration time. This paper also gives a mathematical model of image motion of this system analogous with satellite-borne TDI CCD  and detailed descriptions on the principle utilizing area-array CCD to simulate TDI CCD. It is shown that experiment results are in accordance with mathematical simulation  and that the image quality deteriorate seriously when the correspondence between the image velocity and signal charges transfer velocity is broken out  which suggest not only the validity of the system design but also the validity of the proposed image motion theory of TDI CCD. 2010 SPIE.  
Earth elevation map production and high resolution sensing camera imaging analysis (EI CONFERENCE) 会议论文  OAI收割
Optoelectronic Imaging and Multimedia Technology, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Dai L.
收藏  |  浏览/下载:140/0  |  提交时间:2013/03/25
The Earth's digital elevation which impacts space camera imaging has prepared and imaging has analysed. Based on matching error that TDI CCD integral series request of the speed of image motion  statistical experimental methods-Monte Carlo method is used to calculate the distribution histogram of Earth's elevation in image motion compensated model which includes satellite attitude changes  orbital angular rate changes  latitude  longitude and the orbital inclination changes. And then  elevation information of the earth's surface from SRTM is read. Earth elevation map which produced for aerospace electronic cameras is compressed and spliced. It can get elevation data from flash according to the shooting point of latitude and longitude. If elevation data between two data  the ways of searching data uses linear interpolation. Linear interpolation can better meet the rugged mountains and hills changing requests. At last  the deviant framework and camera controller are used to test the character of deviant angle errors  TDI CCD camera simulation system with the material point corresponding to imaging point model is used to analyze the imaging's MTF and mutual correlation similarity measure  simulation system use adding cumulation which TDI CCD imaging exceeded the corresponding pixel horizontal and vertical offset to simulate camera imaging when stability of satellite attitude changes. This process is practicality. It can effectively control the camera memory space  and meet a very good precision TDI CCD camera in the request matches the speed of image motion and imaging. 2010 SPIE.  
Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Zhang X.-J.;  Wang X.;  Wang X.;  Wang X.;  Wang X.-K.
收藏  |  浏览/下载:40/0  |  提交时间:2013/03/25
In Computer Controlled Optical Surfacing (CCOS)  polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric  a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result  the power factors cosist of three elements include constant  error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end  an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one  especially the rms convergence rate. Theory of the algorithm is simple and exercisable  and it satisfies practical requirement as well. 2009 SPIE.  
Research on method of measuring the time of remote explosion point (EI CONFERENCE) 会议论文  OAI收割
27th International Congress on High-Speed Photography and Photonics, September 17, 2006 - September 22, 2006, Xi'an, China
作者:  
Zhou J.;  Fu Y.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25