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	A method to estimate the neutral atmospheric density near the ionospheric main peak of Mars 期刊论文 OAI收割 JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, 2016, 卷号: 121, 期号: 4, 页码: 3464-3475 作者: Zou, Hong; Ye, Yu Guang; Wang, Jin Song; Nielsen, Erling; Cui, Jun 收藏 \| 浏览/下载：27/0 \| 提交时间：2016/10/27 The neutral densities at 130 km can be derived fromtheMGS/RS measurements with our method The derived neutral densities can be used to verify or calibrate the Martian atmospheric model The method can be applied to other radio occultation measurements such as MEX/RS measurements
	Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：62/0 \| 提交时间：2013/03/25 The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope the structure should have high stiffness and high reliability and light weight. Compared with invar aluminum alloy and titanium alloy carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages such as ultra-light weight high stiffness and dimensional stability etc. The optimization method and the baffle design can be helpful to other coaxial telescopes such as Cassegrain Gregorian and their subdivisions. 2012 IEEE.
	Line-of-sight locating algorithm for staring imaging aerial remote sensor (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 作者: Li Y.; Li Y.; Li Y.; Li Y.; Li J. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 A line-of-sight (LOS) Locating algorithm for staring imaging is presented in this paper. Staring imaging is an imaging mode for aerial remote sensor which photographs the designated earth-fixed target in muItidirections. Therefore the details of interesting targets is available. For the target obscured or disguised its advantage becomes more apparent. This paper proposes the method using two-axis rotation to achieve staring imaging and establishes the system model and the associated coordinates. Adopting the method of coordinate transformation the LOS Locating algorithm is constructed which determines the LOS direction. For the validation of algorithm Target Geolocation Algorithm is established using Simulink library blocks. Eventually it proves the feasibility of the LOS Locating algorithm. This article provides a thought of LOS Locating algorithm for staring imaging. The method of coordinate transformation used in this paper can be applied to line-of-sight positioning in other imaging modes. 2010 IEEE.