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	Design of high speed and parallel compression system used in the big area CCD of high frame frequency (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Precision Engineering and Non-Traditional Machining, PENTM 2011, December 9, 2011 - December 11, 2011, Xi'an, China 作者: Li G.-N.; Jin L.-X.; Zhang R.-F.; Wang W.-H.; Li G.-N. 收藏 \| 浏览/下载：51/0 \| 提交时间：2013/03/25 According to the area CCD camera of characteristics such as high resolution capacity and high frame frequency this paper puts forward a high speed and parallel image compression system of high integration degree. Firstly according to the work principle of the area CCD FPGA is adopted to realize the timing driving and multichannel and parallel analog signal handling to raise the export frame frequency of the area CCD. Secondly with an image compression scheme based on FPGA embedded processor MicroBlaze and ADV212 compression chip real time image compression and the high speed area CCD are realized. Finally by detecting the analog signal of the area CCD output the real time compression of the big area CCD image is carried out in different compression ratios and the compression performance is analyzed. Experiment result shows that this scheme can realize real time image compression with the biggest data rate of 520Mbps. When compression bit ratio is 0.15 the signal-to-noise ratio of peak value can reach 36 dB. Image collection and image compression are integrated which reduces the data transmission between them and improves systematic integration degree.
	Research on infrared dim-point target detection and tracking under sea-sky-line complex background (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: Dong Y.-X.; Zhang H.-B.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：108/0 \| 提交时间：2013/03/25 Target detection and tracking technology in infrared image is an important part of modern military defense system. Infrared dim-point targets detection and recognition under complex background is a difficulty and important strategic value and challenging research topic. The main objects that carrier-borne infrared vigilance system detected are sea-skimming aircrafts and missiles. Due to the characteristics of wide field of view of vigilance system the target is usually under the sea clutter. Detection and recognition of the target will be taken great difficulties.There are some traditional point target detection algorithms such as adaptive background prediction detecting method. When background has dispersion-decreasing structure the traditional target detection algorithms would be more useful. But when the background has large gray gradient such as sea-sky-line sea waves etc.The bigger false-alarm rate will be taken in these local area.It could not obtain satisfactory results. Because dim-point target itself does not have obvious geometry or texture feature in our opinion from the perspective of mathematics the detection of dim-point targets in image is about singular function analysis.And from the perspective image processing analysis the judgment of isolated singularity in the image is key problem. The foregoing points for dim-point targets detection its essence is a separation of target and background of different singularity characteristics.The image from infrared sensor usually accompanied by different kinds of noise. These external noises could be caused by the complicated background or from the sensor itself. The noise might affect target detection and tracking. Therefore the purpose of the image preprocessing is to reduce the effects from noise also to raise the SNR of image and to increase the contrast of target and background. According to the low sea-skimming infrared flying small target characteristics the median filter is used to eliminate noise improve signal-to-noise ratio then the multi-point multi-storey vertical Sobel algorithm will be used to detect the sea-sky-line so that we can segment sea and sky in the image. Finally using centroid tracking method to capture and trace target. This method has been successfully used to trace target under the sea-sky complex background. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Non-linear compensation algorithm of LOS locating in aerial remote sensor (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China 作者: Li J.; Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 A non-linear light-of-sight(LOS) locating compensation algorithm for certain aerial remote sensor is presented in this paper. The LOS locating system is composed of two main components which are an inertial reference frame to provide coarse LOS locating and a 2-axis Fast Steering Mirror to remove the frame's residual error. The azimuth and elevation of LOS are both affected by the FSM two-degree-of-freedom rotation which should be dealt with to raise the accuracy of LOS location. This paper extrapolates LOS locating algorithm of FSM by coordinate transformation and gives corresponding deviation analysis for different LOS poiting angles. It is found that the angle deviation grows rapidly with range of FSM's travel enlarging so the deviation must be eliminated. Through the data analysis for deviation a non-linear compensation algorithm is proved effective to reduce the error of LOS significantly. Taking LOS changing in [-3 deg 3 deg] as an example two analytic expressions are given and the LOS locating accuracy rises by 34 times compared with non-linear compensation unused and the cross coupling of LOS loating is 0.08%. 2011 IEEE.
	A 3-axis simulator for spacecraft attitude control research (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Information and Automation, ICIA 2010, June 20, 2010 - June 23, 2010, Harbin, Heilongjiang, China 作者: Dai L. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 This article presents the details of a new 3-axis simulator for spacecraft attitude control research and simulation. The air bearing allows the test bed to rotate about three axes with tiny friction. The attitude determination system consists of three fibre optical gyros an inclinometer and a magnetometer. The actuator of the system consists of three reaction flywheels and four control moment gyros (CMG). Mathematical models of the sensors and actuators are given to help algorithm design. An extended Kalman filter was designed to provide attitude information for controller. Mathematical simulation results prove the attitude determination system can achieve high precision. A coulomb friction model of reaction wheels is given with experimental results. A friction compensation algorithm was developed to raise the pointing accuracy of the control system. The article also describes the details of the hardware structure. A PD stabilizing controller is implemented to test the validation of the whole control system at last. 2010 IEEE.
	An algorithm of Bayesian networks parameters learning based on confidence interval (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China 作者: Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 This paper focuses on an interval parameter estimation of Bayesian Networks (BNs). Contrast to the point estimation used in most parameter learning algorithms interval estimation algorithm (IEA) estimates the output nodes parameter of BNs with an interval estimation based on confidence level it can raise BNs inference accuracy slightly as the prior knowledge is absence. 2010 IEEE.
	Malnutrition in China's rural boarding schools: the case of primary schools in Shaanxi Province SCI/SSCI论文 OAI收割 2009 Luo R. F.; Shi Y. J.; Zhang L. X.; Liu C. F.; Rozelle S.; Sharbono B. 收藏 \| 浏览/下载：23/0 \| 提交时间：2012/06/08 malnutrition boarding school western rural China mothers education economic-status child health household nutrition height raise
	Plant water sources in the cold semiarid ecosystem of the upper Kherlen River catchment in Mongolia: A stable isotope approach SCI/SSCI论文 OAI收割 2007 Li S. G.; Romero-Saltos H.; Tsujimura M.; Sugimoto A.; Sasaki L.; Davaa G.; Oyunbaatar D. 收藏 \| 浏览/下载：20/0 \| 提交时间：2012/06/08 ecohydrology deuterium (D) oxygen-18 ((18)O) Larix sibirica water use Mongolia RAISE soil-water seasonal-variation hydrogen isotopes amazon basin precipitation forest resource savanna desert oxygen
	Evapotranspiration from a Mongolian steppe under grazing and its environmental constraints SCI/SSCI论文 OAI收割 2007 Li S. G.; Asanuma J.; Kotani A.; Davaa G.; Oyunbaatar D. 收藏 \| 浏览/下载：24/0 \| 提交时间：2012/06/08 Mongolian steppe eddy covariance evapotranspiration leaf area index Priestley-Taylor parameter raise carbon-dioxide exchange water-vapor flux measurements energy-balance temperate grassland prairie ecosystem heat-flux evaporation drought scale