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	Asymptotic behaviors of solutions to quasilinear elliptic equations with Hardy potential 期刊论文 OAI收割 JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS, 2016, 卷号: 441, 期号: 1, 页码: 211-234 作者: He, Cheng-Jun; Xiang, Chang-Lin 收藏 \| 浏览/下载：23/0 \| 提交时间：2016/07/12 Quasilinear elliptic equations Hardy's inequality Asymptotic behaviors Comparison principle
	A Local Image Enhancement Method Based on Adjacent Pixel Gray Order-preserving Principle 会议论文 OAI收割 5th International Symposium on Photoelectronic Detection and Imaging (ISPDI) - Infrared Imaging and Applications, Beijing, June 25-27, 2013 作者: Fan XP(范晓鹏); Cai TF(蔡铁峰); Zhu F(朱枫) 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/12/26 The paper is committed in local image enhancement. At first, the authors propose an adjacent pixel gray order-preserving principle. Adjacent pixel gray order-preserving principle is the basement of local enhancement method which ensures that there is no distortion in processed image. And then, the authors propose an iterative algorithm, which could stretch gray-scale difference of adjacent pixels in premise of not changing gray magnitude relationship between adjacent pixels. At last, the authors propose a totally reference image quality assessment method based on adjacent pixel gray order-preserving principle. According to this quality assessment method, the authors made a set of comparative experiments with local histogram equalization and method. Experimental results show that the proposed enhancement method can get higher score and provide better visual effects, fully demonstrating its effectiveness. According to this quality assessment method, the proposed method shows a good effectiveness, through experimental results and comparison with local histogram equalization method.
	The measuring method for low rotational speed with the frequency difference generated by radial gratings (EI CONFERENCE) 会议论文 OAI收割 2012 International Applied Mechanics, Mechatronics Automation Symposium, IAMMAS 2012, September 7, 2012 - September 9, 2012, Shenyang, Liaoning, China Guo W.-l.; Qiao Y.-f. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 The new method has been proposed based on the comparison and analysis of the traditional methods for measuring rotating speed. It can guarantee real-time property with radial gratings at measuring low speed. It is clearly explained that the fundamental principle for measuring rotating speed and characters of the method and presented the constitution of the system hardware and the process flows. (2012) Trans Tech Publications Switzerland.
	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：19/0 \| 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.
	Control strategies and error compensation methods of high precision gyro stabilized platform (EI CONFERENCE) 会议论文 OAI收割 30th Chinese Control Conference, CCC 2011, July 22, 2011 - July 24, 2011, Yantai, China Deng K.; Cong S.; Shen H. 收藏 \| 浏览/下载：30/0 \| 提交时间：2013/03/25 Based on the principle of gyroscope and the structure of gyro stabilized platform this paper gives the analysis and comparison of control strategies for stable platform included classical PID control and three kinds of advanced strategies: Fuzzy Control Sliding Mode Variable Structure Control and Active Disturbance Rejection Control. The compensation methods for stable platform's error are also discussed and evaluated based on the sources of error especially for the non-linear friction and gyro drift. The paper provides the reliable methods for recognizing and improving the accuracy of gyro stabilized platform from the control strategies and error compensations. 2011 Chinese Assoc of Automation.
	Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Zhang X.-J.; Wang X.; Wang X.; Wang X.; Wang X.-K. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 In Computer Controlled Optical Surfacing (CCOS) polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result the power factors cosist of three elements include constant error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one especially the rms convergence rate. Theory of the algorithm is simple and exercisable and it satisfies practical requirement as well. 2009 SPIE.
	Test of an off-axis asphere by subaperture stitching interferometry (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: Zheng L.-G.; Zhang X.-J.; Zhang Z.-Y.; Zhang Z.-Y.; Deng W.-J. 收藏 \| 浏览/下载：54/0 \| 提交时间：2013/03/25 A new method combined subaperture stitching with interferometry(SSI) is introduced. It can test large and off-axis aspheric surfaces without the aid of other null optics. In this paper the basic principle and theory of the technique are analyzed. The synthetical optimization stitching model and effective stitching algorithm are established based on homogeneous coordinates transformation and simultaneous least-squares method. The software of SSI is devised and the prototype for testing of large aspheres by SSI is designed and developed. An off-axis asphere with the aperture of 376mm188mm is tested by this method. For comparison and validation and the difference of PV and RMS error between them is 0.047 e and 0.006 e the asphere is also tested by null compensation.The synthesized surface profile is consistent to that ofthe entire surface from null test respectively. So it provides another quantitative measurement for testing large aspheric surfaces and off-axis aspheres besides null-compensation. 2009 SPIE.