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	Analysis of zenith pass problem in a roll-pitch optics seeker (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China 作者: Jiang H. 收藏 \| 浏览/下载：35/0 \| 提交时间：2013/03/25 There are mainly two kind of structures for a missile two-axes seeker which is always mentioned as elevate-azimuth and roll-pitch. The elevate-azimuth structured seeker has been studied for a long time and it is applied in all sort of missiles. Not only structure design but also control algorithm of the elevate-azimuth seeker are deeply developed. But for elevate-azimuth seeker there are several disadvantages such as big size and large abaxial angle blind. So the elevate-azimuth seeker gimbal angle is designed up to 65 according to relative references. In modern air war it is important for a missile to have the ability of "first recognize" and "first attack". That means the air to air missile seeker is required to be a system with large gimbal angle and large abaxial launch angle. With the mentioned requirement roll-pitch seeker with its advantages smart size and large gimbal angle is studied widely and deeply. The pitch angle of roll-pitch is up to 90 while its roll angle up to n 360. But there are also some disadvantages for the roll-pitch seeker the most troublesome one is the zenith pass problem. The zenith pass problem is brought about from the gimbal kinematics it is said that when target moves in the center of image plane roll servo command gotten from the kinematics algorithm will go to infinite. Math model of zenith pass problem is proposed in this paper and two ways to solve the problem are brought forward. 2011 IEEE.
	Electro-optical imaging system identification using pseudo-random binary pattern (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 Le Y.; Jian W.; Jianzhong Z.; Qiang S.; Jianzhuo L. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 A method using pseudo-random binary pattern is developed for electro-optical imaging system identification. The imaging system is taken as a stable linear time-invariant and causal filter and its transfer function is measured through the pseudo-random binary sequence impulse responses identification. A digital mirror device (DMD) light projector is developed as the target generator and wavelet thresholding is used to denoise the captured image. Pre-filtering spectral estimation algorithm with adaptive parameter selection is also proposed for the identification process overcoming the challenge brought by the size limit derived from the optical isoplantic region. Simulations and experiments are presented to show the effectiveness of the proposed method.0-64. 2010 IEEE.
	The research of H mixed sensitivity method for line-of-sight stabilization for Carrier-Based theodolite (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 Hua C. L.; Bin G. H.; Mei Z. S. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 In view of the requirements of isolating disturbances and stabilizing optical axis of Carrier-Based theodolite A two-axis stabilizated platform system with the rate gyro was designed The expressions of line-of-sight add-angle velocity begotten by ship-swaying is introduced The principles of selection of weighting of fuctions are brought and adopting H Mixed Sensitivity Method in the velocity Stabilization-loop. 2010 IEEE.
	Modulation transfer function measurement of sampled imaging systems in field test (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: Yang L.; Zhang J.; Zhang J.; Zhang J.; Wang J. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 A digital mirror device (DMD) based light projector was developed as the target generator in modulation transfer function (MTF) measurement. In order to overcome the sampling-scene phase effect in MTF measurement of sampled imaging systems a method using random targets is introduced to yield a phase-averaged MTF. The main potential problem of implementing this method is the fact that the stationary assumption of the random targets may be vitiated in practical measurement especially in field test due to the ill condition. We provide an efficient model-independent way of analyzing and isolating the spectral contents arising from these additional contributions to MTF measurement. Algorithms with adaptive parameter selection were also developed for spectral estimation of the test image in order to overcome the challenge brought by the size limit of the test matrices for one certain field of view derived from the isoplantic region. The MTF measurement of a CCD video imager is used to demonstrate the measurement technique and illustrate the benefits over other methods. In order to validate the results comparisons have been made between MTF measurements of imager implemented using this method and bar target direct measurements. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Study of removing striping noise in CCD image (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu H.; Liu H.; Liu H. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 Striping noise is the common system noise during formation of image using linear array CCD and has the character of periodicity directivity and banding distributing. It can be caused by errors in internal calibration devices or by slight gain/offset differences among the elements that conform the array of detectors. Striping noise covers up useful information in CCD image and brings adverse effect to image interpretation. On the basis of analyzing wavelet decomposed coefficient the regularities of distribution about striping noise in wavelet coefficient is found thereby the method of wavelet threshold selection which is suitable to striping noise distribution is put forward. According to Donoho's method about denoising using wavelet the image including striping noise is processed. Comparing the power spectrum of processed image with the one of original image polluted by striping noise in frequency field we find pulse brought by striping noise is removed and the goal which reserves image details and reduces stripes is achieved.
	Study on integrated vehicle navigation system of "Beidou" double-star/DR (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Devices and Instruments, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu J.; Liu J.; Liu J.; Liu H.; Liu H. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Vehicle navigation is the corn element of Intelligent Transport System. The integrated system of "Beidou" Double-star/DR is studied in this paper according to the present state of vehicle navigation in our country. "Beidou" Double-star navigation position system is one regional satellite position system built up by our country which can provide rapidly not only highly precision position and brevity telegram service. However when the vehicles go around the tall buildings high mountain area wayside trees and in the tunnels all signal may not be received. If the satellite navigation position system is used only the precision will be reduced. Therefore this paper proposes a nonlinear self-adaptive Kalman filter model and its algorithm for a Double-star/DR integrated navigation system in land vehicles and verifies effectively the algorithm and scheme through the means of simulation. Next this paper introduces map match approach. The roads are segmented and character information is brought out. Then proper search rules and map match algorithm are adopted. According to the current vehicle position information that Double-Star/DR system provides the nearest road can be found in the map database. The vehicle position will be matched and displayed on the road. The result of the experiment shows that the Double-star/DR integrated algorithm and map match can improve reliability and the precision of vehicle navigation system efficiently.
	COSMOGENIC RADIONUCLIDES OF NINGQIANG CHONDRITE FROM NONDESTRUCTIVE GAMMA-RAY SPECTROMETRY 期刊论文 OAI收割 Science Bulletin, 1986, 期号: 2, 页码: 115-117 作者: Chai ZF(柴之芳); Su Q(苏琼); Mao XY(毛雪瑛); Ma SL(马淑兰); Wang SC(王思潮) 收藏 \| 浏览/下载：19/0 \| 提交时间：2015/12/07 belongs preliminary GAMMA widespread brought neutron isotopes Jilin atter irradiation