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	Structure Evolution During Uniaxial Tensile Deformation of High Density Polyethylene Before and After Irradiation by 1 MeV Electrons 期刊论文 OAI收割 JOURNAL OF APPLIED POLYMER SCIENCE, 2014, 卷号: 131, 期号: 10 Rui, EM; Yang, JQ; Li, XJ; Liu, CM; Tian, F; Gao, F; Li, XH; Geng, HB 收藏 \| 浏览/下载：52/0 \| 提交时间：2015/03/13 X-RAY-SCATTERING MOLECULAR-WEIGHT POLYETHYLENE STRAIN-INDUCED CRYSTALLIZATION NEAR-EARTH SPACE SYNCHROTRON-RADIATION PLASTIC-DEFORMATION LINEAR POLYETHYLENE SMALL-ANGLE RATES SAXS
	Effect of 110 keV electrons on the deformation mechanisms of low density polyethylene 期刊论文 OAI收割 POLYMER DEGRADATION AND STABILITY, 2014, 卷号: 109, 页码: 59—70 Rui, EM; Yang, JQ; Li, XJ; Liu, CM; Tian, F 收藏 \| 浏览/下载：61/0 \| 提交时间：2015/03/13 X-RAY-SCATTERING MOLECULAR-WEIGHT POLYETHYLENE STRAIN-INDUCED CRYSTALLIZATION NEAR-EARTH SPACE SYNCHROTRON-RADIATION UNIAXIAL DEFORMATION TENSILE DEFORMATION PLASTIC-DEFORMATION LINEAR POLYETHYLENE SMALL-ANGLE
	Design of motion adjusting system for space camera based on ultrasonic motor (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 作者: Sun Z. 收藏 \| 浏览/下载：112/0 \| 提交时间：2013/03/25 Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system which is composed of the drift adjusting mechanical frame the ultrasonic motor the driver of Ultrasonic Motor the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system was introduced the source of the disturbance and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space simple configuration high position control precision fine repeatability self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent. 2011 SPIE.
	Study on spectrograph for ionosphere: A broadband imaging instrument prototype for far-ultraviolet (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 作者: Wang S.-R.; Lin G.-Y.; Yu L. 收藏 \| 浏览/下载：57/0 \| 提交时间：2013/03/25 Current research on space-based exploration for the ionosphere needs more advanced technologies. Because the spectral signals in the ionosphere distributing basically in the far-ultraviolet waveband are very weak. Usual spectrometer structures and detectors such as CCD can't receive enough information. Based on this principle of atmospheric sounding the imaging spectrometer prototype for ionosphere detection application was designed to solve the problem. This prototype consists of the telescope and the imaging spectrometer. The simple structure and small number of mirrors can help higher transmission efficiency be achieved and weak signals detection be implemented. The telescope is an off-axis parabolic mirror and the spectrometer is a modified Czerny-Turner spectral imaging system. Modified Czerny-Turner spectrometer contains a spherical mirror a fixed plane grating and a toroidal mirror. By adjusting the incident angle to the collimating mirror and using toroidal mirror coma and astigmatism were corrected well. We also optimize distances between the grating to the focusing mirror and the focusing mirror to the image plane to improve disadvantages of traditional Czerny-Turner structure. Designed results demonstrate that aberrations are substantially corrected and high image quality can be obtained in broad waveband. The photon counting Wedge-Strip-Anode detector with micro-channel planes as the receiving plane is accepted for the instrument prototype. The other photon counting 2-D detector responding well for weak light such as Cross-Delay line detector and MAMA detector can also be used for detection. The calibration and performances testing system is made of a vacuum system a deuterium lamp a monochrometer and the instrument prototype. Results obtained from the experiment show that the spectral resolution is 2.4 nm and the spatial resolution is 80 m. The other calibration experiments are running. The technology of the spectrometer prototype is important for the research and applications of ionosphere remote sensing. 2011 SPIE.
	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：62/0 \| 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 study of combined invariants optimization method on aircraft recognition 会议论文 OAI收割 2011 symposium on photonics and optoelectronics, sopo 2011, wuhan, china, may 16, 2011 - may 18, 2011 ZhuXufeng; MaCaiwen 收藏 \| 浏览/下载：43/0 \| 提交时间：2012/07/09 aircraft recognition small space angle combined invariants support vector machine
	A study on atmospheric turbulence effects in full-optical free-space communication systems (EI CONFERENCE) 会议论文 OAI收割 2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China 作者: Liu P. 收藏 \| 浏览/下载：44/0 \| 提交时间：2013/03/25 Next generation free-space optical communication systems have used fiber-optic technology as the seamless connection between free-space and optical fiber. The full-optical free-space optical communication systems use optical fiber as the receiver to get faster communication speed. The atmospheric turbulence deeply influenced on the optical wave propagated in terrestrial application. As the active receiving area of the full-optical free-space optical communication systems is very small it is important to research on the atmospheric turbulence effects on the full-optical free-space optical communication system. In this paper we discuss about both the turbulence-induced intensity fluctuations and the angle-of-arrival effects in full-optical free-space optical communication systems which are used in a few kilometers communication. We gave the numerical results of the atmosphere turbulence effects on the free-space optical communication systems. In order to minimize the atmospheric turbulence influence on the full-optical free-space optical communications system we also investigate the use of fine tracking system in the communication system. We have set up a full-optical free-space communication system in Tokyo and received useful data from the experiment. We compared the receiving power of the experiment when the fine tracking system is On and Off. From the experiment results we can see that the fine tracking system effectively mitigates the atmospheric turbulence and increases the receiving power of the communication system. 2010 IEEE.
	Analysis of inertia dyadic uncertainty for small agile satellite with control moment gyros (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: Zhang L.; Zhang L.; Sun Z. 收藏 \| 浏览/下载：34/0 \| 提交时间：2013/03/25 With the increasing demands for the agility of the next earth imaging satellite control moment gyro (CMG) is considered to be the most suitable actuator because of its torque amplification capability. However a CMG system may introduce uncertainty of inertia dyadic to a satellite's attitude control system. The uncertainty is negligible for large space vehicles but it has not been tested whether it can be ignored for small agile satellites. How to model the CMG system inertia dyadic varying with gimbal angles and what influence it will put on the performance of attitude control system haven't been test accurately as well. All of them are dealt with mathematically and accurately in this paper. This paper firstly gives mathematic descriptions of the inertia dyadic of the 4-CMG pyramid configuration system varying with gimbal angles and then designs a variable structure control law for small agile satellite using CMGs. Finally numerical simulation suggests that the inertia dyadic variation of a 4-CMG pyramid configuration system is approximately centesimal of the total inertia dyadic of the satellite and that the designed variable structure control law is of good robust performance for an example of large-angle attitude maneuver despite of the variation of the inertia dyadic. 2010 IEEE.