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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.  
RETRIEVAL OF SINGLE SCATTERING ALBEDO OF WINTER WHEAT IN NORTH CHINA PLAIN BASED ON AMSR-E DATA 会议论文  OAI收割
2012 Ieee International Geoscience and Remote Sensing Symposium, New York
Wu, Fengmin; Chai, Linna; Zhang, Lixin; Jiang, Lingmei; Yang, Juntao
收藏  |  浏览/下载：27/0  |  提交时间：2014/12/07
The effect of backlash nonlinear on resonance frequency of electric actuator transmission system (EI CONFERENCE) 会议论文  OAI收割
3rd IEEE International Conference on Advanced Computer Control, ICACC 2011, January 18, 2011 - January 20, 2011, Harbin, China
Han X.; Ge M.; Bai Y.; Jia H.; Ge W.
收藏  |  浏览/下载：25/0  |  提交时间：2013/03/25
In order to study the effect of backlash nonlinear on resonance frequency of electric actuator transmission system  then  Finally  in the premise of meeting the stability  the dynamic equilibrium equation of transmission system with backlash is established  it makes dynamic simulation analysis for the transmission system based on virtual prototype technology  it establishes balanced equation of dynamics system with backlash  the effect of backlash on system natural frequency and resonance frequency  and the theoretical values and simulation values are compared. Theoretical analysis and simulation results show that the theoretical analysis is basically consistent with simulation results when it is zero backlash  and does some theory research and dynamic analysis of backlash nonlinearity and system natural frequency and resonance frequency. First  and the error of theoretical analysis and simulation results is within 10%. Therefore  according to describing function to theoretically model the backlash nonlinear  it can be concluded that considering the transmission system theoretical analysis of backlash nonlinearity is feasible  the relation between describing function and the amount of backlash and input amplitude is analyzed  and it is much closer to the actual system with instructive significance. 2011 IEEE.  
ASSESSMENT OF BOREAL FOREST BIOMASS USING L-BAND RADIOMETER SMOS DATA 会议论文  OAI收割
2011 Ieee International Geoscience and Remote Sensing Symposium, New York
Zhang, Ning; Shi, Jiancheng; Sun, Guoqing; Guo, Zhifeng; Chai, Linna
收藏  |  浏览/下载：32/0  |  提交时间：2014/12/07
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：41/0  |  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.  
Space optics remote sensor focusing components mechanics characteristic analysis based on FEM (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China
作者:  Wang B.;  Ren J.-Y.;  Wang B.
收藏  |  浏览/下载：162/0  |  提交时间：2013/03/25
Space optical remote sensor is very important in many fields of science and military significance. It is widely applied. Space optical remote sensor design and manufacturing require precision and stability. Focusing mechanics is an important component of remote sensors. Focusing mechanics can guarantee the stability of the entire mechanics focusing accuracy  therefore the stability of research focusing mechanics is very important. In order to guarantee the space optics remote sensor focusing mechanics the stability  takes steps the space optics remote sensor focusing organization mechanics characteristic analysis from the classics contact theory. This article uses international general non-linear finite element analysis software ABAQUS to carry on mechanics characteristic analysis to the space optics remote sensor focusing mechanics. First acts according to the focusing mechanics unique feature  carries on the finite element to the structural model the grid division  the material attribute disposition and the boundary condition indeed grades. Then establishment contact non-linear finite element model  and to focusing organization finite element model infliction unit action. Like this contacts the result and the equivalent static analysis result which the nonlinear analysis obtains carries on the contrast and the analysis. This article last count result modality is 90HZ  satisfies the space optics remote sensor structure overall modality to request to be bigger than 50HZ.This article when carries on the dynamic analysis  extracts the structure kinetic energy and the acceleration curve. In the dynamic analysis obtained transient response analysis modality 70.5Hz  this also is bigger than 50HZ. The dynamic analysis indicated the structure dynamic stability has the distinct enhancement  has provided certain foundation for the space optics remote sensor following development work  reduced the overall system development cycle. 2009 SPIE.  
A high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文  OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China
作者:  Sun Y.;  Sun Y.;  Wan Q.-H.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid  according to the difficulties of the detection of the magnetic fluid  established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all  the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer  collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid  which followed the movement of the magnetic fluid  and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA  whose width and depth were designed by the user as required. Then  the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus  whose transmission rate can reach 480Mb/s in theory. Finally  the distribution of the laser speckle on the magnetic fluid was messy and random  which carried certain information about the surface of the magnetic fluid  based on the theories of the statistic correlation and the subdivision of images  analysing and processing the laser speckle interferometric images  indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court  non-contact  non-invasive  high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps  which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.  
Magnetic properties of Ising metamagnet in both external longitudinal and transverse fields 期刊论文  OAI收割
Journal of Magnetism and Magnetic Materials, 2009, 卷号: 321, 期号: 13, 页码: 1964-1970
J. J. Geng; G. Z. Wei
收藏  |  浏览/下载：22/0  |  提交时间：2012/04/13
Phase transitions and multicritical points in the mixed spin-3/2 and spin-2 Ising model with different single-ion anisotropies 期刊论文  OAI收割
Journal of Magnetism and Magnetic Materials, 2009, 卷号: 321, 期号: 24, 页码: 4139-4144
H. L. Miao; G. Z. Wei; J. J. Geng
收藏  |  浏览/下载：18/0  |  提交时间：2012/04/13
The phase diagrams of a spin-1 transverse Ising model 期刊论文  OAI收割
Journal of Magnetism and Magnetic Materials, 2009, 卷号: 321, 期号: 2, 页码: 102-107
H. L. Miao; G. Z. Wei; J. Liu; J. J. Geng
收藏  |  浏览/下载：28/0  |  提交时间：2012/04/13