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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:23/0  |  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.  
Image deblurring with adaptive total variation model (EI CONFERENCE) 会议论文  OAI收割
International Conference on Image Processing and Pattern Recognition in Industrial Engineering, August 7, 2010 - August 8, 2010, Xi'an, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
Inhibition of electromagnetic interference in control system based on DSP of high-power TEA CO2 laser (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:  
Meng F.-J.;  Guo L.-H.;  Wang H.-Q.
收藏  |  浏览/下载:44/0  |  提交时间:2013/03/25
The strong electromagnetic interference (EMI) generated in high-power TEA C02 laser system mainly comes from main discharge circuit  pulse spark switch and power supply. Such strong EMI causes great damage and interference to the control system based on DSP. In this paper  we present the interference sources and their distribution and propose the methods of anti-interference. Measures for hardware design include weakening transient ground potential difference by using equipotential lines between devices  using signal isolation interface to inhibit the transient ground potential interference  and rational layout  shielding and filtering to the control system. And methods for software design include range-limited filter  self-diagnosis and self-repair for the critical data and anti-interference during abnormal reset. The EMI has been inhibited effectively by the anti-interference method proposed above. The result shows that: the software anti-interference method is as important as the hardware anti-interference method for the control system in a complex environment of strong EMI. 2010 IEEE.  
Resolution performance of extreme ultraviolet telescope (EI CONFERENCE) 会议论文  OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China
作者:  
Yang L.;  Chen B.;  Chen B.;  Liang J.-Q.;  Ni Q.-L.
收藏  |  浏览/下载:33/0  |  提交时间:2013/03/25
Extreme Ultraviolet Telescope (EUT) will image solar corona in four EUV narrow bandpasses defined by multilayered coatings deposited on normal incidence optics. In order to make sure it will get sub-arcsecond angular resolution in the mission we have to test its resolution performance on ground. The EUT is aligned by Zygo interferometer first and a global wavefront error of 0.152 peak to valley is obtained ( = 632.8nm ). Because of the difficulty of angular resolution test for EUT at its operating wavelengths  we test its optical performance at visible and UV band. The method is to place the resolution test-target on the focal plane of collimator and illuminate the target by visible and UV light espectively  then the collimated light will go through EUT and image at focal plane on CCD. By analysis of the images obtained in experiments we conclude that the angular resolution of EUT is 1.22 at visible light ( = 570nm ) which is very close to diffraction limit (1.20) and according to these results we estimate that the operational wavelength resolution is better than 0.32  meets design requirements. While for UV light  the angular resolution is 1.53 that is different from diffraction limit (0.53)  the error comes mainly from large pixel of EUV camera. 2009 SPIE.  
High-accuracy real-time automatic thresholding for centroid tracker (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Zhang Y.
收藏  |  浏览/下载:38/0  |  提交时间:2013/03/25
Many of the video image trackers today use the centroid as the tracking point. In engineering  we can get several key pairs of peaks which can include the target and the background around it and use the method of Otsu to get intensity thresholds from them. According to the thresholds  it give a great help for us to get a glancing size  a target's centroid is computed from a binary image to reduce the processing time. Hence thresholding of gray level image to binary image is a decisive step in centroid tracking. How to choose the feat thresholds in clutter is still an intractability problem unsolved today. This paper introduces a high-accuracy real-time automatic thresholding method for centroid tracker. It works well for variety types of target tracking in clutter. The core of this method is to get the entire information contained in the histogram  we can gain the binary image and get the centroid from it. To track the target  so that we can compare the size of the object in the current frame with the former. If the change is little  such as the number of the peaks  the paper also suggests subjoining an eyeshot-window  we consider the object has been tracked well. Otherwise  their height  just like our eyes focus on a target  if the change is bigger than usual  position and other properties in the histogram. Combine with this histogram analysis  we will not miss it unless it is out of our eyeshot  we should analyze the inflection in the histogram to find out what happened to the object. In general  the impression will help us to extract the target in clutter and track it and we will wait its emergence since it has been covered. To obtain the impression  what we have to do is turning the analysis into codes for the tracker to determine a feat threshold. The paper will show the steps in detail. The paper also discusses the hardware architecture which can meet the speed requirement.  the paper offers a idea comes from the method of Snakes  
关于Skyrme模型的一些新结果(英文) 期刊论文  OAI收割
中国科学技术大学学报, 1988, 期号: 5, 页码: 510-514
作者:  
李炳安;  沈齐兴;  阎沐霖
收藏  |  浏览/下载:17/0  |  提交时间:2015/12/10