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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：43/0 \| 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.
	The sequence measurement system of the IR camera (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang H.-B.; Han H.-X.; Geng A.-H. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 Currently the IR cameras are broadly used in the optic-electronic tracking optic-electronic measuring fire control and optic-electronic countermeasure field but the output sequence of the most presently applied IR cameras in the project is complex and the giving sequence documents from the leave factory are not detailed. Aiming at the requirement that the continuous image transmission and image procession system need the detailed sequence of the IR cameras the sequence measurement system of the IR camera is designed and the detailed sequence measurement way of the applied IR camera is carried out. The FPGA programming combined with the SignalTap online observation way has been applied in the sequence measurement system and the precise sequence of the IR camera's output signal has been achieved the detailed document of the IR camera has been supplied to the continuous image transmission system image processing system and etc. The sequence measurement system of the IR camera includes CameraLink input interface part LVDS input interface part FPGA part CameraLink output interface part and etc thereinto the FPGA part is the key composed part in the sequence measurement system. Both the video signal of the CmaeraLink style and the video signal of LVDS style can be accepted by the sequence measurement system and because the image processing card and image memory card always use the CameraLink interface as its input interface style the output signal style of the sequence measurement system has been designed into CameraLink interface. The sequence measurement system does the IR camera's sequence measurement work and meanwhile does the interface transmission work to some cameras. Inside the FPGA of the sequence measurement system the sequence measurement program the pixel clock modification the SignalTap file configuration and the SignalTap online observation has been integrated to realize the precise measurement to the IR camera. Te sequence measurement program written by the verilog language combining the SignalTap tool on line observation can count the line numbers in one frame pixel numbers in one line and meanwhile account the line offset and row offset of the image. Aiming at the complex sequence of the IR camera's output signal the sequence measurement system of the IR camera accurately measures the sequence of the project applied camera supplies the detailed sequence document to the continuous system such as image processing system and image transmission system and gives out the concrete parameters of the fval lval pixclk line offset and row offset. The experiment shows that the sequence measurement system of the IR camera can get the precise sequence measurement result and works stably laying foundation for the continuous system. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Laser pulse coded signal frequency measuring device based on DSP and CPLD (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Laser Sensing and Imaging; and Biological and Medical Applications of Photonics Sensing and Imaging, May 24, 2011 - May 26, 2011, Beijing, China 作者: Zhang H.-B.; Wang T.-F.; Guo R.-H.; Li Y.; Li Y. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 Laser pulse code is an anti-jamming measures used in semi-active laser guided weapons. On account of the laser-guided signals adopting pulse coding mode and the weak signal processing it need complex calculations in the frequency measurement process according to the laser pulse code signal time correlation to meet the request in optoelectronic countermeasures in semi-active laser guided weapons. To ensure accurately completing frequency measurement in a short time it needed to carry out self-related process with the pulse arrival time series composed of pulse arrival time calculate the signal repetition period and then identify the letter type to achieve signal decoding from determining the time value number and rank number in a signal cycle by Using CPLD and DSP for signal processing chip designing a laser-guided signal frequency measurement in the pulse frequency measurement device improving the signal processing capability through the appropriate software algorithms. In this article we introduced the principle of frequency measurement of the device described the hardware components of the device the system works and software analyzed the impact of some system factors on the accuracy of the measurement. The experimental results indicated that this system improve the accuracy of the measurement under the premise of volume real-time anti-interference low power of the laser pulse frequency measuring device. The practicality of the design reliability has been demonstrated from the experimental point of view.
	808nm high-power semiconductor laser therapeutic apparatus based on LPC2138 (EI CONFERENCE) 会议论文 OAI收割 2011 IEEE International conference on Intelligent Computation and Bio-Medical Instrumentation, ICBMI 2011, December 14, 2011 - December 17, 2011, Wuhan, Hubei, China 作者: Wang B.; Wang B. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In this paper we designed an intelligent 808nm high-power semiconductor laser therapeutic apparatus with the LPC2138 ARM processor. The laser is driven by the digital constant current source module and the apparatus has good human-machine interaction performance on account of set the parameters intelligently. The function such as operation mode output power output pulse width and pulse cycle could be easily set through the TFT touch screen. The application software could transmission the log data to the computer by the USB interface in order to check and study the records later. 2011 IEEE.
	Image parallel processing based on GPU (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: Wang J.-L.; Wang J.-L. 收藏 \| 浏览/下载：31/0 \| 提交时间：2013/03/25 In order to solve the compute-intensive character of image processing based on advantages of GPU parallel operation parallel acceleration processing technique is proposed for image. First efficient architecture of GPU is introduced that improves computational efficiency comparing with CPU. Then Sobel edge detector and homomorphic filtering two representative image processing algorithms are embedded into GPU to validate the technique. Finally tested image data of different resolutions are used on CPU and GPU hardware platform to compare computational efficiency of GPU and CPU. Experimental results indicate that if data transfer time between host memory and device memory is taken into account speed of the two algorithms implemented on GPU can be improved approximately 25 times and 49 times as fast as CPU respectively and GPU is practical for image processing. 2010 IEEE.
	Solitary kinetic Alfven waves in dusty plasmas 期刊论文 OAI收割 PHYSICS OF PLASMAS, 2008, 卷号: 15, 期号: 8, 页码: 083703 作者: Li, Yang-fang; Wu, D. J.; Morfill, G. E. 收藏 \| 浏览/下载：30/0 \| 提交时间：2011/12/29 Solitary kinetic Alfven waves in dusty plasmas are studied by Considering the dust charge variation. The effect of the dust charge-to-mass ratio on the soliton solution is discussed. The Sagdeev potential is derived analytically with constant dust charge and then calculated numerically by taking the dust charge variation into account. We show that the dust charge-to-mass ratio plays an important role in the soliton properties. The soliton solutions are comprised of two branches. One branch is sub-Alfvenic and the soliton velocity is obviously smaller than the Alfven speed. The other branch is super-Alfvenic and the soliton velocity is very close to or greater than the Alfven speed. Both compressive and rarefactive solitons can exist. For the sub-Alfvenic branch the rarefactive soliton is bell-shaped and it is much narrower than the compressive one. However for the super-Alfvenic branch the compressive soliton is bell-shaped and narrower and the rarefactive one is broadened. When the charge-to-mass ratio of the dust grains is sufficiently high the width of the rarefactive soliton in the super-Alfvenic branch will broaden extremely and a electron depletion will be observed. It is also shown that the bell-shaped soliton can transition to a cusped structure when the velocity is sufficiently high. (C) 2008 American Institute of Physics.
	Algorithm research of flexible graphplan based on heuristic (EI CONFERENCE) 会议论文 OAI收割 9th International Conference for Young Computer Scientists, ICYCS 2008, November 18, 2008 - November 21, 2008, Zhang Jia Jie, Hunan, China 作者: Xu S.; Wang X.; Wang X.; Wang X.; Sun Y. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Classic Graphplan has too much restriction on capturing the full subtlety of many real problems. Flexible Graphplan is defined which supports the soft constraints often found in reality. Heuristic concept is introduced to the process of plan extraction in flexible graphplan in order to improve the efficiency of plan extraction and the quality of plan. A novel algorithm using the new heuristic function which is applied by improved sum mutex heuristic to deal with planning problems is proposed. Sum mutex heuristic which is in common use as heuristic function takes into account only static propositional mutexes and ignores the mutexes of actions. The performance of the new algorithm on many benchmark problems is remarkably robust. It can solve many planning problems which can't be solved by the heuristic state space search planning system using sum mutex heuristic. 2008 IEEE.
	Medical X-ray coherent scatter images processing based on the MRF model (EI CONFERENCE) 会议论文 OAI收割 ICO20: Biomedical Optics, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu J.; Liu J.; Liu J. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 X-ray coherent scatter imaging is a novel imaging technique. A clinical X-ray coherent scatter imaging equipment based on image processing method is introduced adopting CR and IP plate instead of the diffractometers. The scatter images obtained are made of some circles with the same center. According to our equipment it is vital to calculate the energy template to classify the different samples. However it is difficult to separate them using the traditional threshold method due to noise and overlapped shadow. Markov Random Field (MRF) is employed to segment the scatter image which takes spatial information into account to deal with the noise and overlapped shadow. The experiment results show our method is reasonable and feasible.
	分布事务处理中的资源管理期刊论文 OAI收割计算机科学, 2003, 卷号: 30, 期号: 4, 页码: 30-32 张昕; 丁柯 \| 收藏 \| 浏览/下载：6/0 \| 提交时间：2011/07/29 Distributed transaction Resource management Resource enlistment Connection pool 分布事务处理资源管理 distributed transaction connection pool scheduling algorithm resource enlistment on account of