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Spatial Downscaling of MSG Downward Shortwave Radiation Product Under Clear-Sky Condition 期刊论文  OAI收割
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 2020, 卷号: 58, 期号: 5, 页码: 3264-3272
作者:  Wang, Wei;  Yin, Gaofei;  Zhao, Wei;  Wen, Fengping;  Yu, Daijun
  |  收藏  |  浏览/下载：36/0  |  提交时间：2020/06/07
Advanced astigmatism-corrected tandem Wadsworth mounting for small-scale spectral broadband imaging spectrometer (EI CONFERENCE) 会议论文  OAI收割
作者:  Lin G.-Y.
收藏  |  浏览/下载：38/0  |  提交时间：2013/03/25
Tandem gratings of double-dispersion mount make it possible to design an imaging spectrometer for the weak light observation with high spatial resolution  high spectral resolution  and high optical transmission efficiency. The traditional tandem Wadsworth mounting is originally designed to match the coaxial telescope and large-scale imaging spectrometer. When it is used to connect the off-axis telescope such as off-axis parabolic mirror  it presents lower imaging quality than to connect the coaxial telescope. It may also introduce interference among the detector and the optical elements as it is applied to the short focal length and small-scale spectrometer in a close volume by satellite. An advanced tandem Wadsworth mounting has been investigated to deal with the situation. The Wadsworth astigmatism-corrected mounting condition for which is expressed as the distance between the second concave grating and the imaging plane is calculated. Then the optimum arrangement for the first plane grating and the second concave grating  which make the anterior Wadsworth condition fulfilling each wavelength  is analyzed by the geometric and first order differential calculation. These two arrangements comprise the advanced Wadsworth mounting condition. The spectral resolution has also been calculated by these conditions. An example designed by the optimum theory proves that the advanced tandem Wadsworth mounting performs excellently in spectral broadband. 2012 Optical Society of America.  
A line mapping based automatic registration algorithm of infrared and visible images 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:  Ai R(艾锐);  Shi ZL(史泽林);  Xu DJ(徐德江);  Zhang CS(张程硕)
收藏  |  浏览/下载：36/0  |  提交时间：2013/12/26
There exist complex gray mapping relationships among infrared and visible images because of the different imaging mechanisms. The difficulty of infrared and visible image registration is to find a reasonable similarity definition. In this paper, we develop a novel image similarity called implicit linesegment similarity(ILS) and a registration algorithm of infrared and visible images based on ILS. Essentially, the algorithm achieves image registration by aligning the corresponding line segment features in two images. First, we extract line segment features and record their coordinate positions in one of the images, and map these line segments into the second image based on the geometric transformation model. Then we iteratively maximize the degree of similarity between the line segment features and correspondence regions in the second image to obtain the model parameters. The advantage of doing this is no need directly measuring the gray similarity between the two images. We adopt a multi-resolution analysis method to calculate the model parameters from coarse to fine on Gaussian scale space. The geometric transformation parameters are finally obtained by the improved Powell algorithm. Comparative experiments demonstrate that the proposed algorithm can effectively achieve the automatic registration for infrared and visible images, and under considerable accuracy it makes a more significant improvement on computational efficiency and anti-noise ability than previously proposed algorithms.  
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.  
Preparation of (R)-2-chloro-1-(m-chlorophenyl)ethanol by Lipozyme TL IM-catalyzed second resolution 期刊论文  OAI收割
CHINESE CHEMICAL LETTERS, 2012, 卷号: 23, 期号: 3, 页码: 289-292
Xia, Shi Wen; Lin, Hui; Chen, Yong Zheng
收藏  |  浏览/下载：26/0  |  提交时间：2013/07/03
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.  
Design of driving circuit for binocular CCD image system (EI CONFERENCE) 会议论文  OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optoelectronic Materials and Devices for Detector, Imager, Display, and Energy Conversion Technology, April 26, 2010 - April 29, 2010, Dalian, China
作者:  Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载：42/0  |  提交时间：2013/03/25
The paper designs a driving circuit of high sensitive  wide dynamic and high signal-to-noise ratio for binocular CCD imaging system which adopts a Dalsa-made high resolution full-frame 33-mega pixels area CCD FTF5066M. Inner structure and driving timing of the FTF5066M sensor are presented. Field Programmable Gate Array (FPGA) is used as the main device to accomplish the timing design of the circuits and power driver control of the two sensors. By using the Correlated Double Sampling (CDS) technique  the video noise is reduced and the SNR of the system is increased. A 12- bit A/D converter is used to improve the image quality. The output rate of the imaging system designed with integrated chip can reach to 1.3 frames per second through bi-channel. For its good performance  low power consumption and small volume  the driving system can be applied to aeronautics and astronautics field. With a further improvement  a maximum data output rate of 2.7 frames per second can be reached through all the eight channels of the two CCDs. 2010 Copyright SPIE - The International Society for Optical Engineering.  
Autocollimation form dual-frequency laser diffraction grating interferometer design and analysis (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
Wang C.-G.
收藏  |  浏览/下载：34/0  |  提交时间：2013/03/25
Propose a new measurement system of autocollimation form laser grating heterodyne interferometer. Take grating diffraction and polarization optics as theoretical foundation  second  furthermore  combined with electronics knowledge to analyze the system. First  make use of autocollimation diffraction of grating  measurement information obtained by dual-frequency laser belongs to ac signal  the interferometer measurement system take grating pitch as measuring datum  the structure is simple  possess great gain and high signal-noise ratio  therefore  stable  completely overcome the disadvantages of DC level drift caused by light intensity variation of single-frequency laser  system can achieve nanometer resolution. 2010 IEEE.  reduce the impact of environmental factors  easy to install and debug  measurement error is small  
Driving and image enhancement for CCD sensing image system (EI CONFERENCE) 会议论文  OAI收割
2010 3rd IEEE International Conference on Computer Science and Information Technology, ICCSIT 2010, July 9, 2010 - July 11, 2010, Chengdu, China
Zhang M.; Ren J.
收藏  |  浏览/下载：28/0  |  提交时间：2013/03/25
The paper designs a driving circuit of high sensitive  wide dynamic for CCD sensing imaging system which adopts a Dalsa-made high resolution full-frame 33-mega pixels area CCD FTF5066M. Field Programmable Gate Array (FPGA) is used as the main device to accomplish the timing design of the circuits and power driver control of the sensor. By using the Correlated Double Sampling (CDS) technique  the video noise is reduced and the SNR of the system is increased. The output rate of the imaging system designed with integrated chip can reach to 1.3 frames per second through bi-channel output. We use the histogram specification to adjust the brightness of the captured image. And then use the median filtering to suppress the noise. The traditional gray mean gradient (GMG) and the objective evaluation method based on Human Visual System (HVS) used to verify the effect of image enhancement. 2010 IEEE.