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等离激元耦合调控的半导体量子点的线性与非线性光学响应研究 学位论文  OAI收割
博士后, 北京: 全国博士后管理委员会, 2016
刘晓娜
收藏  |  浏览/下载：26/0  |  提交时间：2016/06/27
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.  
LED display image correction based on computer simulation (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
Zheng X.-F.; Chang F.
收藏  |  浏览/下载：26/0  |  提交时间：2013/03/25
For the purposes of correcting the LED display image  a method based on computer simulation is proposed. First  the development of the LED display panel is introduced. Second  analyze the causes of the problem which image in LED display panel has serious high nonuniformity  and introduce the existed correction techniques which are used to reduce the nonuniformity of LED display image. Simultaneously  point out the ground for shortcomings of these techniques. Third  describe the principle of correction method based on computer simulation detail from two steps  which are the luminous collection and luminous copulation. Forth  describe the realization steps of this method in accordance with the third step. Finally  this method is supplied in a LED display panel  whose resolution is 640480. Experimental results show that this method is able to reduce the non-uniformity of images from 11.06% to 0.98%. (2012) Trans Tech Publications  Switzerland.  
LED display panel grayscale modulation based on computer calculation (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
Wang R.-g.; Chang F.
收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25
In order to improve the method of the LED display panel grayscale modulation a method based on computer calculation is proposed. First the development history and trends of the LED display panel are introduced. Second present the structure of the LED display panel and the existed modulation method. Simultaneously point out the ground for shortcomings of the existed method. Third describe the principle modulation method based on computer calculation detail from two steps which are the data signal transformation and the grayscale modulation. Forth describe the realization steps of this method in accordance with the third step. Finally this method is supplied in a LED display panel whose resolution is 320240. Experimental results show that this method is able to increase the grayscale from 14-bit to 16-bit and can enhance the display result of the LED display panel significantly. (2012) Trans Tech Publications Switzerland.  
Tracking error modeling of the theodolite based on GRNN method (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Frontiers of Manufacturing and Design Science, ICFMD 2011, December 11, 2011 - December 13, 2011, Taichung, Taiwan
作者:  Li M.
收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25
SGCMG design and time accumulation error analysis (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
Xu W.
收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25
Design of motion compensation mechanism of satellite remote sensing camera (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China
Gu S.; Yan Y.; Xu K.; Jin G.
收藏  |  浏览/下载：47/0  |  提交时间：2013/03/25
With the development of aerospace remote sensing technology  the ground resolution of remote sensing camera enhances continuously. Since there is relative motion between camera and ground target when taking pictures  the target image recorded in recording media is moved and blurred. In order to enhance the imaging quality and resolution of the camera  the image motion had to be compensated. In order to abate the effect of image motion to image quality of space camera and improve the resolution of the camera  the compensation method of image motion to space camera is researched. First  the reason of producing drift angle and adjustment principle are analyzed in this paper. This paper introduce the composition and transmission principle of image motion compensation mechanism. Second  the system adopts 80C31 as controller of drift angle  and adopts stepping motor for actuators  and adopts absolute photoelectric encoder as the drift Angle measuring element. Then the control mathematical model of the image motion compensation mechanism are deduced  and it achieve the closed-loop control of the drift angle position. At the last  this paper analyses the transmission precision of the mechanism. Through the experiment  we measured the actual precision of the image motion compensation mechanism  and compared with the theoretical analysis. There are two major contributions in this paper. First  the traditional image motion compensation mechanism is big volume and quality heavy. This has not fit for the development trend of space camera miniaturization and lightweight. But if reduce the volume and quality of mechanism  it will bring adverse effects for the precision and stiffness of mechanism. For this problem  This paper designed a image motion compensation that have some advantages such as small size  light weight at the same time  high precision  stiffness and so on. This image motion compensation can be applicable to the small optics cameras with high resolution. Second  the traditional mechanism control need to corrected  fitting and iterative for the control formula of mechanism. Only in this way  we can get the optimal control mathematical model. This paper has high precision of the control formula derived. It can achieve the high precision control without fitting  It also simplify the difficulty of control mathematical model establishment. This paper designed the range of adjusting of image motion compensation mechanism between -5 +5. Based on choosing-5  -4  -3  -2  -1  0  +1  +2  +3  +4  +4 as the expectation value of the imaginary drift angle  we get ten groups of the fact data in adjusting drift angle measured. The test results show that the precision of the drift angle control system can be achieved in 1. It can meet the system requirements that the precision of the control system is less than 3'  and it can achieve the high-precision image motion compensation. 2011 SPIE.  
The research of electromachanical actuator control system development based on the MATLAB platform using the RTDX (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者:  Zhang J.;  Zhang Y.;  Zhang J.;  Zhang J.
收藏  |  浏览/下载：43/0  |  提交时间：2013/03/25
In order to rapidly develop the control system code of the Electromachanical Actuator(EMA)  the DSP development platform is established mostly based on the MATLAB  and the development metheod is researched.First  the DSP development platform archtecture in the environment of MATLAB is briefly introduced.And the principle of data exchange is showed.Then  the EMA hardware structure is necessarily explained  which one is for the developer to conveniently configure the system.Finally  the developer reasonably configures the DSP models used in the simulink and constitutes them to speed and position closed loop control system of the EMA  by using the RTDX and the MATLAB GUI. The EMA control system code will be debuged rapidly through this platform.The executed DSP code will be generated automatically.And the result of degugging would be showed on the MATLAB GUI.For generlly speaking  the difficulties of the EMA control system code development method is reduced and the development cycle is shortened through the MATLAB model.This system development method is fast and effective. 2011 IEEE.  
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.  
The explanation of InN bandgap discrepancy based on experiments and first-principle calculations 期刊论文  OAI收割
physics letters a, PHYSICS LETTERS A, 2011, 2011, 卷号: 375, 375, 期号: 7, 页码: 1152-1155, 1152-1155
作者:  Liu CR;  Li JB;  Liu, CR, Chinese Acad Sci, Inst Semicond, State Key Lab Superlattices & Microstruct, POB 912, Beijing 100083, Peoples R China. supermanliu5@semi.ac.cn;  jbli@semi.ac.cn
  |  收藏  |  浏览/下载：65/6  |  提交时间：2011/07/05