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	Three-loop autopilot design and simulation (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Zhang Y. 收藏 \| 浏览/下载：44/0 \| 提交时间：2013/03/25 In order to realize missile real-time change flight trajectory three-loop autopilot is setting up. The structure characteristics autopilot model and control parameters design method were researched. Firstly this paper introduced the 11th order three-loop autopilot model. With the principle of systems reduce model order the 5th order model was deduced. On that basis open-loop frequency characteristic and closed-loop frequency characteristic were analyzed. The variables of velocity ratio dynamic pressure ratio and elevator efficiency ratio were leading to correct system nonlinear. And then autopilot gains design method were induced. System flight simulations were done and result shows that autopilot gains played a good job in the flight trajectory autopilot satisfied the flight index. 2012 IEEE.
	Influencing Factor Analysis of Interference Vibration Reduction of Millisecond Blasting 期刊论文 OAI收割 DISASTER ADVANCES, 2012, 卷号: 5, 期号: 4, 页码: 494-501 作者: Yan Yongfeng; Li Haibo; Zhang Qiuhua; Chen Shihai; Lv Yanxin \| 收藏 \| 浏览/下载：25/0 \| 提交时间：2018/06/05 Waveforms Interference for Vibration Reduction Millisecond Delay Intervals Millisecond Blasting Waveform Superposition Time-frequency Characteristic
	The Research of real time auto-recognition of the moire fringe (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Imaging Detectors and Applications, May 24, 2011 - May 26, 2011, Beijing, China Wang M.-J.; Wu Z.-G. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 Measuring the movement of raster by the method of moire fringe has the advantage of high sensitivity high resolution and non-contacted measurement. The characteristic of moire fringe is that the image is white alternate with black the angle of the stripes is uniform the width of the stripes is uniform the terminators of the stripes aren't clear. A fast method that can figure out the width and angle of the moire fringe precisely is put forward in this paper. It calculates the angle the stripes firstly. According to the principle of the minimum mean squared error (MMSE) the closer a series of data is the smaller the value of the MMSE will be. The method is described as follows: It takes the image's center as the origin 180 beelines pass through the origin with the same angle interval. it calculates the value of the minimum mean squared error of the 180 beelines and find out the least one among those then the angle of the moire fringe comes out primarily. In order to improving the calculating precision of moire fringe 60 equal angles are divided in the neighborhood of the angle then a precise angle of moire fringe is calculated according to the principle of the MMSE. After getting out the angle of the moire fringe we begin to calculate the width of moire fringe. A line vertical with the moire fringe is drawn and we can get the width of the moire fringe by the vertical line. In order to get over the influence of the noise an effective area with the shape of diamond is selected in the image. The data of area is accumulated and projected according to the direction of moire fringe and a sine curve come out. The width of moire fringe can be obtained by getting the position of the first wave crest the position of the last wave crest and the number of wave crest. Experiments prove that the precision of the method put forward in this paper is enhanced in comparison with the traditional frequency method the precision of width calculation achieves to 99.6% according to the evaluation indicators of width detection error. The computing speed is boosted largely compared with traditional method and it can achieve with 15 ms that satisfying the demand of real time. 2011 SPIE.
	Real-time matching algorithm of navigation image based on corner detection (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Advances in Imaging Detectors and Applications, June 17, 2009 - June 19, 2009, Beijing, China 作者: Zhang T. 收藏 \| 浏览/下载：44/0 \| 提交时间：2013/03/25 In order to meet requirement of real-time and high accuracy in image matching aided navigation SSDA algorithm is used to match remote sensing image and template image coarsely a fast and effective algorithm of remote sensing image matching based on corner detection is put forward. With the combination of rough and fine match when the matching result is bigger than one to count absolute value sum of energy difference of characteristic point energy to realize fine match of remote sensing image and template image to locate the position of template image in remote sensing image accurately. Simulation experiment proves that the matching of a remote sensing image resolution of 10181530 and a template image resolution of 15090 can be fulfilled within 2.392 second wavelet transform is used to acquire low frequency component to realize image compression to decrease calculation work and increase matching speed. Harris corner detection algorithm is used to detect corner of remote sensing image and template image and energy of every corner is calculated the algorithm is robust and effective real time image navigation can be achieved. 2009 SPIE.
	飞秒脉冲通过散射表面后的时域特性期刊论文 OAI收割中国激光, 2009, 卷号: 36, 期号: 5, 页码: 1160-1165 刘文军; 任守田; 曲士良; 戴恩文; 周常河收藏 \| 浏览/下载：1244/159 \| 提交时间：2010/05/14 散射时域特性频率分辨光学开关法飞秒脉冲散射表面 scattering time domain characteristic frequency-resolved optical gating femtosecond pulse scattering surface