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	Recommendations for construction of a nonlinear international Terrestrial Reference Frame 期刊论文 OAI收割 SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY, 2011, 卷号: 54, 期号: 1, 页码: 164-171 作者: Zhu WenYao; Song ShuLi; He LiNa 收藏 \| 浏览/下载：26/0 \| 提交时间：2015/08/19 International Terrestrial Reference Frame geocenter motion scale linear to nonlinear definition of ITRF station coordinates the coordinate transformation expression
	The research of nonlinear control based on fuzzy neural network (EI CONFERENCE) 会议论文 OAI收割 International Conference on Electrical and Control Engineering, ICECE 2010, June 26, 2010 - June 28, 2010, Wuhan, China Fan Y.-Y.; Sang Y.-J. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 This paper discussed and researched the structure and algorithm of fuzzy neural network controller based on the character of fuzzy logic and neural network theory. For the nonlinear system characteristics of uncertainty high order and hysteresis this paper used the fuzzy neural network technology to control nonlinear system and improved the control quality obviously. Take the single inverted pendulum for example the paper constructed the nonlinear mathematicmodel realized the control with the method of the adaptive fuzzy neural network and compared with control method of liner quadratic regulator the simulation results indicate that the method of adaptive fuzzy neural network can realize the stabilization of control better without the linear model of system and has a higher robustness. 2010 IEEE.
	The analysis for the reason of limit cycle generated by friction in servo system (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 作者: Li M. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 In this paper limit cycle which results from friction during low-velocity servo system has been discussed. First the piecewise linearization method has been applied to change nonlinear stribeck model to linear model. Second with analysis of equilibrium property it is proved the existence of limit cycle and its certain region. The analysis reveals that it is because of stability of equilibrium repeatedly changing results in the limit cycle during low-velocity state. In addition it also points that the key point to avoid this phenomenon is to keep robust stability of the close-loop system. 2010 IEEE.
	Nonlinear analysis method for predicting optical surface deformations resulted from assembly process (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China Dong W.; Yong Y.; Guang J. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 There are three main nonlinear elements in the large mirror assemblies which are screw pretension adhesive stress and state changes in the assembly process. The optical shape will be influenced seriously by these factors. But the impacts will not be shown in linear analysis results because as the simplification these factors have been ignored. The nonlinear analysis method for predicting optical surface deformations resulted from assembly process is discussed in detail. Take a typical mirror support structure for example the nonlinear analysis model was established. Comparing the calculation results with the optical shape test it is illustrated that nonlinear analysis is more accurate and closer to the test result. And according to the simulation result the bowl-shaped depression which was discovered in the test can also be explained reasonably. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Nonlinear control design for system with mechanical resonance based on two tracking-differentiators (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Mechatronics and Automation, ICMA 2010, August 4, 2010 - August 7, 2010, Xi'an, China 作者: Li J.; Li Y.; Li Y.; Li Y.; Li Y. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 A nonlinear control strategy for controlling a motion system with mechanical resonance is presented in this paper. A mathematical model of the servo system is derived according to the parameters of an actual system. By using two Tracking-Differentiators reference input and system output are tracked and their differential signals are given simultaneously. A nonlinear PD control law in velocity loop is designed based on non-smooth feedback. The simulation results show that the control law is superior remarkably in performance to linear PD control law and the classical PID control law. Tracking-Differentiator resolves the contradiction between rapidity and overshoot of system response. The nonlinear PD control law improves system dynamic performance and intensifies the ability of disturbance rejection. The control design achieved in this paper makes the servo system more robust. 2010 IEEE.
	An efficient color transfer algorithm for recoloring multiband night vision imagery (EI CONFERENCE) 会议论文 OAI收割 Enhanced and Synthetic Vision 2010, April 6, 2010 - April 6, 2010, Orlando, FL, United states 作者: Xu S. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 A color transfer method is presented to give fused multiband nighttime imagery a natural daytime color appearance in a simple and efficient way. Instead of using the traditional nonlinear l space the proposed method transfers the color distribution of the target image (daylight color image) to the source image (fused multiband nighttime imagery) in the linear YCBCR color space. The YCBCR transformation is simpler and more suitable for image fusion compared to the l conversion. The YCBCR transformation can be extended into a general formalism. And the paper mathematically proves that for color transfer using color spaces conforming to this general YC BCR space framework can produce same recoloring results as using the YCBCR space. Experimental results demonstrate that the YCBCR based color transfer method works surprisingly well for transferring natural color characteristics of daylight color images to false color fused multiband nighttime imagery and moreover can also be successfully applied to recoloring a variety of color images. 2010 SPIE.
	An efficient color transfer method for fusion of multiband nightvision images (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Information Engineering and Computer Science, ICIECS 2009, December 19, 2009 - December 20, 2009, Wuhan, China 作者: Xu S. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 We present a color transfer method which is designed to give fused multiband nighttime imagery a natural daytime color appearance in a simple and efficient way. Instead of using traditional nonlinear la space the proposed method transfers the color distribution of the target image (daylight color image) to the source image (fused multiband nighttime imagery) in a linear color space named ICBCR. The ICBCR transformation is simpler than the la conversion moreover the IC BCR space is easily extended to image fusion. Our experiments on infrared and visual images show that the ICBC R based color transfer method works surprisingly well for transferring natural color characteristics of daylight color images to false color fused nighttime imagery. 2009 IEEE.
	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：150/0 \| 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.
	The geometric distortions correction of uncooled large-sized relative aperture infrared imaging system (EI CONFERENCE) 会议论文 OAI收割 Infrared Components and their Applications, November 8, 2004 - November 11, 2004, Beijing, China 作者: Sun Q. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 The geometric distortion of infrared image which was created by the large-sized relative aperture optical system. It could be corrected by the digital image processing technology. The magnitude of distortion would be enlarged quickly with the enlargement of relative aperture. Though the distortion could not impact on the articulation of the image it would affect geometric location precision of the image directly. In this paper the distortion correction of uncooled large-sized relative aperture infrared imaging system was discussed and the mathematical model of distortion correction was established. A algorithm of digital image processing was presented and applied based on control points by combining polynomial warping and space variant linear image interpolation. The method of polynomial warping was used to establish the locality relationship between the original image and the distortion ones. The space-variant linear image interpolation provided an efficient way to rebuild the frame of images. The computational costs of the proposed approach are very little and the precision is almost as high as the method of bicubic interpolation when compared to those of state-of-the-art nonlinear interpolation operators.