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	A new scalable software package for large scale beam dynamic simulations 会议论文 OAI收割 Shanghai, China, May 12, 2013 - May 17, 2013 作者: Li, Ch.; Yang, L.; He, Y.; Zhao, R.; Xu, J. \| 收藏 \| 浏览/下载：16/0 \| 提交时间：2016/03/29 Accelerator Design Hardware And Software Large Scale Simulations New Devices Particle In Cell Method Poisson Solvers Poisson's Equation Space Charge Effects
	Numerical simulation of terahertz generation and detection based on ultrafast photoconductive antennas 会议论文 OAI收割 international symposium on photoelectronic detection and imaging 2011: terahertz wave technologies and applications, beijing, china, may 24, 2011 - may 26, 2012 作者: FanWen-Hui 收藏 \| 浏览/下载：31/0 \| 提交时间：2012/07/09 Terahertz photo-carrier space-charge screening photoconductive antenna
	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：19/0 \| 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.
	Multi-channel high-speed TDICCD image data acquisition and storage system (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on E-Product E-Service and E-Entertainment, ICEEE2010, November 7, 2010 - November 9, 2010, Henan, China 作者: Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 For multi-channel high-speed image data of certain space remote sensing camera this paper proposed a new image data acquisition and storage system. First of all the system uses Field-Programmable Gate Array(FPGA) controlling synchronous dynamic random access memory(SDRAM) array to realize the cache of image data then according to the received commands sends certain channel's image data to the acquisition card to write the image data into SCSI hard disk and implements the final storage. A Time Delay Integral Charge Couple Device(TDICCD) image data acquisition and storage system with five channels is developed pixel clock rate is up to 96MHz total effective data rate is up to 2.88Gb/s single channel storage depth is up to 7810 lines. The experimental results indicate that this system work stably high effectively which can meet the requirement of acquisition and storage of multi-channel high-speed TDICCD image data. 2010 IEEE.
	Real-time adjusting of yaw angle of space camera based on General Image-Quality Equation (EI CONFERENCE) 会议论文 OAI收割 2009 2nd International Conference on Intelligent Computing Technology and Automation, ICICTA 2009, October 10, 2009 - October 11, 2009, Changsha, Hunan, China 作者: Wang J.; He X.; Xu S. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 A Strategy of Real-Time Adjusting of Yaw Angle (SRTAYA) of space camera was proposed base on General Image-Quality Equation (GIQE). During space camera imaging yaw angle which is caused by rotation of the earth and the gesture changing of satellite impacts integral aspect of TDI (Time Delay and Integration) CCD (Charge Couple Device) so that the image quality degrades. For extending imaging time of space camera and enhancing image quality yaw angle must be adjusted. The descending value of GIQE reflects the degrading quantity of image quality. The SRTAYA calculated an acceptable augmenting value of yaw angle according with a specific value of GIQE which the degrading of image quality can't be neglected no longer. The example which actualized a practical orbit of satellite illuminated that the SRTAYA could limit the value of yaw angle less than 318.45". 2009 IEEE.
	Modeling of satellite borne TDI CCD pitching imaging image motion velocity vector (EI CONFERENCE) 会议论文 OAI收割 2009 IEEE International Conference on Automation and Logistics, ICAL 2009, August 5, 2009 - August 7, 2009, Shenyang, China 作者: Zhang L.; Li S.; Zhang L. 收藏 \| 浏览/下载：12/0 \| 提交时间：2013/03/25 In order to obtain three-dimensional observation effect with single satellite borne time delay and integrate charge coupled device (TDI-CCD) pitching imaging is required. More accurate real-time image motion velocity vector computational model of space camera is also necessary to make the imaging perfect. Imaging motion velocity vector computation model must be set up on image plane at pitching imaging. According to the geometric relationship between the pitching imaging space camera and the Earth's rotation motion satellite borne TDI CCD pitching imaging motion velocity vector model is derived by mapping the ground speed to the image plane and using coordinate transformation method. The numerical simulation results show that the image velocity model can reduce deviation angle error about 33' and about 30% image motion speed error compared to traditional ground velocity model. 2009 IEEE.
	Space camera imaging gain in-orbit adjusting strategy (EI CONFERENCE) 会议论文 OAI收割 2009 2nd International Conference on Intelligent Computing Technology and Automation, ICICTA 2009, October 10, 2009 - October 11, 2009, Changsha, Hunan, China 作者: Wang J.; He X. 收藏 \| 浏览/下载：10/0 \| 提交时间：2013/03/25 A Multi-Step Gain Adjusting Strategy (MSGAS) of space camera was proposed which was used to get higher SNR (Signal-Noise Rate) image. When the space camera working in poor light condition the CCD signal was so weak that it's difficult to get a clear image to reduce the quantization noise and improve the SNR we must amplify the CCD signal first and then quantize. The MSGAS was achieved by adjusting the gain of the CCD (Charge Couple Device) signal processor step by step the upper limit and lower limit were set if the MDN (Mean Digital Number) of a fixed length image data was not between the lower and upper limit the gain was adjusted step by step. In the experiment the upper limit lower limit and the step were set and the result of the experiment showed that MSGAS was robust and SNR was improved from 28 to 39. 2009 IEEE.