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	VEGETATION PATTERNS IN A NEW-BORN COASTAL WETLAND IN THE YELLOW RIVER DELTA, CHINA 期刊论文 OAI收割 FRESENIUS ENVIRONMENTAL BULLETIN, 2015, 卷号: 24, 期号: 12A, 页码: 4465-4471 作者: Wang, XH; Li, YZ; Dong, HF; Tong, SZ 收藏 \| 浏览/下载：34/0 \| 提交时间：2016/04/24 Composition structure species diversity spatial distribution influenced factors
	Precision analysis of simulation systems with hardware-in-loop caused by performance of three-Axis virtual flight motion simulator (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Manufacturing Science and Technology, ICMST 2011, September 16, 2011 - September 18, 2011, Singapore, Singapore Wang T.; Zhu M.-C.; Yin S.-L.; Jia H.-G. 收藏 \| 浏览/下载：48/0 \| 提交时间：2013/03/25 Simulation systems with hardware-in-loop are composed by three-Axis virtual flight motion simulator simulation computer load torque simulator and visual simulation systems. Three-Axis Virtual Flight Motion Simulator are used to simulate the attitude of missile in simulation system with hardware-in-loop so its performance influenced the result of simulation directly. This paper mainly analyzed the factors which influenced the performance of a three-Axis virtual flight motion simulator which we are used now in the lab then analyzed the entire simulation system's error caused by these factors through numerical simulation method. By analysis we can see that bandwidth is the main factor influenced the precision of simulation systems with hardware-in-loop mechanical device installation error and measurement error may also cause some errors of the systems at the same time.
	Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China 作者: Zhang Z.-D. 收藏 \| 浏览/下载：48/0 \| 提交时间：2013/03/25 Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	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.
	Design and analysis of large spaceborne light-weighted primary mirror and its support system (EI CONFERENCE) 会议论文 OAI收割 3rd International Symposium on Advanced Optical Manufacturing and Testing Technologies, AOMATT 2007: Large Mirrors and Telescopes, July 8, 2007 - July 12, 2007, Chengdu, China Yan Y.; Jin G.; Yang H.-B. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 With the development of the resolution of spaceborne remote sensor the diameter of the primary mirror of spaceborne telescope becomes larger and larger. The distortion of primary mirror which is influenced by the mirror material structure self-weight support system and temperature environment affects optical image quality finally. In this paper an on-axis TMA high-resolution Cassegrain optical payload with a primary mirror whose diameter is 650mm was designed and the effects of the influence factors of the distortion acts on the on-axis TMA optical system primary mirror had been analyzed by means of Finite Element Analysis. During work the technology of the primary mirror design had been summarized and general consideration of the primary mirror design technology also had been described at the same time. Considering the telescope manufacture and work station a reasonable and optimal structure of the primary mirror sub-assembly is taken finally. In the end the distortion of the primary mirror during its fabrication station and work station had been analyzed by integrated Finite Element Analysis Method. The results implicated the synthesis profile error (P-V value) for the primary mirror is less than /10 and all the indexes of the primary mirror satisfy the requirements of the optical system.