中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
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A multiscale reconstructing method for shale based on SEM image and experiment data 期刊论文  OAI收割
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING, 2019, 卷号: 179, 页码: 586-599
作者:  
Ji LL(姬莉莉);  Lin M(林缅);  曹高辉i;  Jiang WB(江文滨);  Ji LL(姬莉莉)
  |  收藏  |  浏览/下载:61/0  |  提交时间:2019/09/09
High precision test method for dynamic imaging of space camera (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States
作者:  
Jin L.-X.;  Zhang K.;  Zhang K.;  Zhang K.;  Zhang K.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
A test method for dynamic imaging of space TDICCD (Time Delay and Integration Charge Coupled Devices) camera was presented in this paper. The test method adopted the PLL (Phase Locked Loop) technology and CMAC (Cerebella Model Articulation Controller) friction compensation as control strategy. Furthermore  According to this method  a test system for dynamic imaging of space TDICCD camera was designed and implemented. The system simulated the movement of the ground objects relative to the space aerocraft  to validate the capability of image speed match and the dynamic imaging quality of TDICCD camera. The design adopted a precision turntable and a drift turntable to simulate the movement around the earth and the drift motion in different latitude due to the rotation of earth  of the aerocraft. The turntables were drived by permanent magnet torque motor which was powered by PWM (Pulse Width Modulation). The system adopted DSP (Digital Signal Processor) as the control core and reached a very high performance. The experimental results showed that the steady speed error was better than 0.01 % and the instantaneous speed error reached 0.0267%. The precision of the test system designed met the requirement for dynamic imaging of TDICCD camera. 2010 IEEE.  
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:141/0  |  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.  
CMOS APS imaging system application in star tracker (EI CONFERENCE) 会议论文  OAI收割
Advanced Materials and Devices for Sensing and Imaging II, November 8, 2004 - November 10, 2004, Beijing, China
作者:  
Li J.;  Liu Y.;  Liu Y.;  Liu Y.;  Liu J.
收藏  |  浏览/下载:58/0  |  提交时间:2013/03/25
Small satellites are capable of performing space explore missions that require accurate attitude determination and control. However  low weight  size  power and cost requirements limit the types of attitude sensor of small craft  such as CCD  are not practical for small satellites. CMOS APS is a good substitute for attitude sensors of small craft. Some of the technical advantages of CMOS APS are no blooming  single power  low power consumption  small size and little support circuitry  direct digital output  simple to system design  in particular  radiation-hard characteristic compare with CCD. This paper discusses the application probability of CMOS APS in star tracker for small satellites  further more  a prototype ground-based star camera based on STAR250 CMOS image sensor has been built. In order to extract stars positions coordinates  subpixel accuracy centroiding algorithm has been developed and tested on some ground-based images. Moreover  the camera system star sensitivity and noise model are analyzed  and the system accuracy is been evaluated. Experimental results indicate that a star camera based on CMOS APS is a viable practical attitude sensor appropriate for space small satellites.