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A fast target recognition algorithm based on MSA and MSR (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Industrial Control and Electronics Engineering, ICICEE 2012, August 23, 2012 - August 25, 2012, Xi'an, China
作者:  
Wang Y.;  Liu G.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:31/0  |  提交时间:2013/03/25
The research on statistical properties of TDI-CCD imaging noise (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
Gu Y.-Y.; Shen X.-H.; He G.-X.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
TDI-CCD can improve the sensitivity of space camera without any degradation of spatial resolution which is widely used in aerospace imaging devices. The article describes the basic working principle and application characteristics of TDI-CCD devices  analyses the composition of TDI-CCD imaging noise  and propose a new method to analyze TDI-CCD imaging noise with statistical probability distribution. In order to estimate the distribution of gray values affect by noise we introduced the concept of skewness and kurtosis. We design an experiment using constant illumination light source  take image with TDI-CCD working at different stage such as stage 16  stage 32  stage 48  stage 64 and stage 96  analyse the characteristics of image noise with the method we proposed  experimental results show that the gray values approximately meet normal distribution in large sample cases. 2011 SPIE.  
A design of beam shaping unit for 193nm lithography illumination system using angular spectrum theory (EI CONFERENCE) 会议论文  OAI收割
6th International Symposium on Precision Engineering Measurements and Instrumentation, August 8, 2010 - August 11, 2010, Hangzhou, China
作者:  
Zhao Y.;  Zhang W.;  Zhang W.;  Li S.;  Gong Y.
收藏  |  浏览/下载:17/0  |  提交时间:2013/03/25
Off-axis illumination (OAI) technology is widely used to enhance resolution for deep ultraviolet lithography. The realizing methods of OAI include geometrical optics method and physical optics method. However  the former has the disadvantage of weak intensity distribution controlling ability  and the latter introduces simulation errors evidently when dealing with near field diffraction propagation. A diffractive optical element (DOE) designing method using plane wave angular spectrum theory is presented in this paper. Several kinds of OAI modes at near field away from DOE can be realized  and simulation errors and the size of illuminator are also reduced. According to studying the relationships of the sampling point distance of DOE  light beam propagation distance  and the structure of the beam shaping unit  a method of determining the designing parameters is discussed. Using this method  several illumination modes are realized  and simulation results show that all diffraction efficiencies reach up to 84%. The method of DOE manufacturing is analyzed at last  and it is proven to be feasible. 2010 SPIE.  
The calibration of faint simulation star magnitude based on single photon count technique (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:  
Xu S.-Y.;  Guo J.;  Guo J.
收藏  |  浏览/下载:34/0  |  提交时间:2013/03/25
A calibration method of faint star magnitude of the star scene simulation device is proposed in this paper. In the research of simulation star magnitude  luminometers and CCD devices are the general calibration devices which are used to measure the illumination intensity and calibrate its magnitude. But if the simulation magnitude is only sixth magnitude  its illumination intensity is only 1.010-8 Lux. This illumination intensity level is the lowest illumination intensity that the commercial luminometer can detect. Hence the simulation star magnitude lower than six magnitude cannot be calibrated by luminoters. Likewise CCD devices also need an additive cooler in this case. When the single photon characteristic is presented due to the low luminosity of simulating light sources  the simulation star magnitude can be calibrated by detecting its photon flux of radiation with the method of single photon count. In this paper the detection principle of single photon based on a compact designed PMT detecting of the radiation level of simulation star magnitude is advanced. Especially a spectrum match method is proved theoretically to be an effective means for selecting PMT photosensitive type. In the case of the detection object of the simulation star in visible wavelength  a analysis indicates that the material of tri-alkali cathode materials its best choice after being compared the Signal-to-Noise of photon detector of several PMT photosensitive materials based on the different spectrum match ratio of different object light sources and different cathode materials. An experiment is employed to show the relationship of control voltage of PMT and its dark counter  the relationship of the environment temperature of PMT and its dark counter  which proves its only decades of CPS at room temperature. The so low dark counter avoids a bulky cooler and is convenient for installing it on the star scene simulation equipment. Finally in the experiment of calibrating the simulation star magnitudes the ability of its calibration is confirmed to reaches up to 12m  meanwhile its calibration error is within 0.2m. 2009 SPIE.  
Affine object recognition and affine parameters estimation based on covariant matrix (EI CONFERENCE) 会议论文  OAI收割
2008 International Symposium on Information Science and Engineering, ISISE 2008, December 20, 2008 - December 22, 2008, Shanghai, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:145/0  |  提交时间:2013/03/25
A new method of affine object recognition and affine parameters estimation is presented. For a real-time image and a group of templates  in addition  firstly  on the basis of correct recognition  we segment the object regions in them and compute their covariant matrices. Secondly  it can estimate affine parameters exactly  normalize the ellipse regions defined by covariant matrices to circle regions to get rotational invariants  and the estimated error is within 3%. 2008 IEEE.  and compute the similarity function value between rotational invariants of real-time image and every template respectively. Then compare the values with threshold set in advance  if more than one value is larger than threshold  take the corresponding templates as candidates  and compute affine matrix between real-time image and every candidate. Finally  transform the realtime image with every affine matrix and match the result with corresponding candidate by classical matching methods. Experimental results show that the presented method is robust to illumination  with low computational complexity  and it can realize recognition of different affine objects  
Integrated intensity, orientation code and spatial information for robust tracking (EI CONFERENCE) 会议论文  OAI收割
2007 2nd IEEE Conference on Industrial Electronics and Applications, ICIEA 2007, May 23, 2007 - May 25, 2007, Harbin, China
作者:  
Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
real-time tracking is an important topic in computer vision. Conventional single cue algorithms typically fail outside limited tracking conditions. Integration of multimodal visual cues with complementary failure modes allows tracking to continue despite losing individual cues. In this paper  we combine intensity  orientation codes and special information to form a new intensity-orientation codes-special (IOS) feature to represent the target. The intensity feature is not affected by the shape variance of object and has good stability. Orientation codes matching is robust for searching object in cluttered environments even in the cases of illumination fluctuations resulting from shadowing or highlighting  etc The spatial locations of the pixels are used which allow us to take into account the spatial information which is lost in traditional histogram. Histograms of intensity  orientation codes and spatial information are employed for represent the target Mean shift algorithm is a nonparametric density estimation method. The fast and optimal mode matching can be achieved by this method. In order to reduce the compute time  we use the mean shift procedure to reach the target localization. Experiment results show that the new method can successfully cope with clutter  partial occlusions  illumination change  and target variations such as scale and rotation. The computational complexity is very low. If the size of the target is 3628 pixels  it only needs 12ms to complete the method. 2007 IEEE.  
Key techniques of laser direct writing patterns on spherical substrate (EI CONFERENCE) 会议论文  OAI收割
3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Design, Manufacturing, and Testing of Micro- and Nano-Optical Devices and Systems, July 8, 2007 - July 12, 2007, Chengdu, China
作者:  
Zhao J.-L.;  Feng X.-G.
收藏  |  浏览/下载:26/0  |  提交时间:2013/03/25
Comparing with the writing method of plane pattern  spherical pattern' has some remarkable different on several points. Firstly  it is difficult to spin-coated a uniform photoresist film on a spherical substrate  especially the ratio of spherical radius to caliber is smaller  and the spin-coated way must match the ratio of spherical radius to caliber. Secondly  if the sphere couldn't be regarded as a plane  a so-called concentric optical scan movement way must be applied for the generation of spherical pattern  because the reflex of substrate will affect the quantity of illumination. Commonly  an alignment technique is indispensable with pattern generation of spherical surface by the concentric optical scan in order to ensure the orthogonal intersection of focusing laser beam and writing surface. Thirdly  a uniform velocity control must be considered for the laser direct writing method on a spherical substrate. Otherwise  the exposure time of photoresist will be different  and the line widths of pattern will be also different at different areas. Fourthly  commonly  because the errors of concentric machine and substrate surface shape are bigger  so focusing servo-control technique is also needful for writing a pattern on a spherical substrate. Focusing servo-control may keep the focal spot on the spherical surface by a focus detection and control system in the course of writing pattern. Using these techniques  we fabricated a line width of 7m and a period of 600m isometric mesh on the concave of a spherical substrate.  
Effects of different light sources and illumination methods on growth and body color of shrimp Litopenaeus vannamei 期刊论文  OAI收割
AQUACULTURE, 2006, 卷号: 252, 期号: 2-4, 页码: 557-565
作者:  
You, K;  Yang, HS;  Liu, Y;  Liu, SL;  Zhou, Y
  |  收藏  |  浏览/下载:17/0  |  提交时间:2010/12/24
Target track system design based on circular projection (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
Song H.-J.; Zhu M.; Hu S.; Shen M.-L.
收藏  |  浏览/下载:22/0  |  提交时间:2013/03/25
Template matching is the process of searching the present and the location of a reference image or an object in a scene image. Template matching is a classical problem in a scene analysis: given a reference image of an object  decide whether that object exists in a scene image under analysis  and find its location if it does. The template matching process involves cross-correlating the template with the scene image and computing a measure of similarity between them to determine the displacement. The conventional matching method used the spatial cross-correlation process which is computationally expensive. Some algorithms are proposed for this speed problem  such as pyramid algorithm  but it still can't reach the real-time for bigger model image. Moreover  the cross-correlation algorithm can't be effective when the object in the image is rotated. Therefore  the conventional algorithms can't be used for practical purpose. In this paper  an algorithm for a rotation invariant template matching method based on different value circular projection target tracking algorithm is proposed. This algorithm projects the model image as circular and gets the radius and the sum of the same radius pixel value. The sum of the same radius pixel value is invariable for the same image and the any rotated angle image. Therefore  this algorithm has the rotation invariant property. In order to improve the matching speed and get the illumination invariance  the different value method is combined with circular projection algorithm. This method computes the different value between model image radius pixel sum and the scene image radius pixel sum so that it gets the matching result. The pyramid algorithm also is been applied in order to improve the matching speed. The high speed hardware system also is been design in order to meet the real time requirement of target tracking system. The results show that this system has the good rotate invariance and real-time property.