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浏览/检索结果: 共8条，第1-8条 帮助 限定条件 内容类型：会议论文     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Geometric phase gradient and spin Hall effect of light 会议论文 Spintronics IX, San Diego, CA, United states, August 28, 2016 - September 1, 2016 作者:  Ling, Xiaohui*;  Zhou, Xinxing;  Qiu, Cheng-Wei 收藏  |  浏览/下载：6/0  |  提交时间：2019/12/24 Geometric phase gradient  Spin Hall effect of light  Metamaterial   Optimum design of the carbon fiber thin-walled baffle for the space-based camera (EI CONFERENCE) 会议论文 International Symposium on Photoelectronic Detection and Imaging 2011: Space Exploration Technologies and Applications, May 24, 2011 - May 26, 2011, Beijing, China Yan Y.; Gu S.; An Y.; Jin G. 收藏  |  浏览/下载：10/0  |  提交时间：2013/03/25 The thin-walled baffle design of the space-based camera is an important job in the lightweight space camera research task for its stringent quality requirement and harsh mechanical environment especially for the thin-walled baffle of the carbon fiber design. In the paper  an especially thin-walled baffle of the carbon fiber design process was described and it is sound significant during the other thin-walled baffle design of the space camera. The designer obtained the design margin of the thin-walled baffle that structural stiffness and strength can tolerated belong to its development requirements through the appropriate use of the finite element analysis of the walled parameters influence sensitivity to its structural stiffness and strength. And the designer can determine the better optimization criterion of thin-walled baffle during the geometric parameter optimization process in such guiding principle. It sounds significant during the optimum design of the thin-walled baffle of the space camera. For structural stiffness and strength of the carbon fibers structure which can been designed  the effect of the optimization will be more remarkable though the optional design of the parameters chose. Combination of manufacture process and design requirements the paper completed the thin-walled baffle structure scheme selection and optimized the specific carbon fiber fabrication technology though the FEM optimization  and the processing cost and process cycle are retrenchment/saved effectively in the method. Meanwhile  the weight of the thin-walled baffle reduced significantly in meet the design requirements under the premise of the structure. The engineering prediction had been adopted  and the related result shows that the thin-walled baffle satisfied the space-based camera engineering practical needs very well  its quality reduced about 20%  the final assessment index of the thin-walled baffle were superior to the overall design requirements significantly. The design method is reasonable and efficient to the other thin-walled baffle that mass and work environment requirement is requirement harsh. 2011 SPIE.   Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China Zhang X.; Jiang Z.; Wei Q.; Jia H. 收藏  |  浏览/下载：29/0  |  提交时间：2013/03/25 A concentric glass spherical dome was usually chosen as the transparent window mounted in front of the optical lens in an image seeker. However  optical ray had to change its direction when propagating through the dome due to refraction unless passing through the center of the dome  which demanded gimbal point coincide with the center of the dome exactly. In fact  gimbal point displacement could not be eliminating due to fabrication  assembly and vibration  therefore the optical axis pointing error generated. In this paper  the effect of gimbal point displacement on optical axis pointing precision in an image seeker was analyzed  and the theoretical expression of the optical axis pointing error was derived based on geometric optics  and the error dynamics was explored by numerical. Take a visible light image seeker as a case  the thickness of concentric glass spherical dome was 8mm and the inner radius was 72mm  and the optical axis pointing errors varying dynamically with the look angle and the gimbal point displacement were shown in graph. When the gimbal displacement was 0.11mm  the maximum optical axis pointing error was 0.054mrad that is equal to the instantaneous field of view (IFOV) corresponding to the camera system whose focal length was 120mm and pixel size was 6.5m. Furthermore  with the gimbal displacement increasing  the optical axis pointing error increased linearly. The analyzed results provided a theoretical basis for the displacement range  which had to be limited strictly in the gimbal design process. 2011 IEEE.   Geometric error analysis on OLED units' three-dimensional microstructure in ink-jet printing process 会议论文 作者:  Yao, Yiyong;  Zhao, Liping 收藏  |  浏览/下载：4/0  |  提交时间：2019/12/10 Calculation formula  Classification models  Effect factors  Geometric errors  OLED  Thickness errors  Three-dimensional microstructures   Water vapor cooling effects in turning by finite element modeling 会议论文 Guilin, China, April 9, 2011 - April 11, 2011 作者:  Yang, Fan;  Huang, Jian Long 收藏  |  浏览/下载：0/0  |  提交时间：2020/11/15 Computer software  Cooling  Cutting tools  Finite element method  Manufacture  Metal cutting  AISI 1045  Cooling conditions  Cooling effects  Cutting process  Cutting temperature  Effect of water  Experimental validations  FEM  FEM simulations  Finite element modeling  Finite element software  Geometric modeling  Material modeling  Metal cutting process  Simulation result  Turning process   Modeling of satellite borne TDI CCD pitching imaging image motion velocity vector (EI CONFERENCE) 会议论文 2009 IEEE International Conference on Automation and Logistics, ICAL 2009, August 5, 2009 - August 7, 2009, Shenyang, China Zhang L.; Li S.; Jin G.; Yang X. 收藏  |  浏览/下载：12/0  |  提交时间：2013/03/25 In order to obtain three-dimensional observation effect with single satellite borne time delay and integrate charge coupled device (TDI-CCD)  pitching imaging is required. More accurate real-time image motion velocity vector computational model of space camera is also necessary to make the imaging perfect. Imaging motion velocity vector computation model must be set up on image plane at pitching imaging. According to the geometric relationship between the pitching imaging space camera and the Earth's rotation motion  satellite borne TDI CCD pitching imaging motion velocity vector model is derived by mapping the ground speed to the image plane and using coordinate transformation method. The numerical simulation results show that the image velocity model can reduce deviation angle error about 33' and about 30% image motion speed error compared to traditional ground velocity model. 2009 IEEE.   Gradient index microwave lens using metal strip 会议论文 2009 International Conference on Microwave Technology and Computational Electromagnetics, ICMTCE 2009, Beijing, China, November 3, 2009 - November 6, 2009 作者:  Mei, Zhong Lei;  Niu, Tiao Ming;  Cui, Tie Jun 收藏  |  浏览/下载：5/0  |  提交时间：2017/01/18 Strip metal  Computational electromagnetics  Electromagnetic field theory  Electron optics  Lenses  Metals  Microwave devices  Microwaves  Optical instruments  Effective medium theories  Electromagnetic parameters  Electromagnetic properties  Field distribution  Focusing effect  Geometric sizes  Gradient indexes  Metal strip array  Metal strips  Theoretical basis  Theoretical prediction   Active pixel sensor geometrical characteristic effects on star image subdivided locating accuracy for star tracker (EI CONFERENCE) 会议论文 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China Li J.; Liu J.; Hao Z. 收藏  |  浏览/下载：21/0  |  提交时间：2013/03/25 Active pixel sensor (APS) star tracker becomes an investigated hotspot because of its technical advantages. And centroid algorithm is a subpixel method proper to star position calculation because of its high accuracy and simplicity. When centroid algorithm is applied on APS star tracker  APS pixel geometrical characteristics might effect on star image position accuracy. Because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area  the Fill Factor is less than 100%. Moreover  the active sensitive area has a certain geometrical shape  such as square  rectangle and L shape. The Fill Factor of pixel influences on star image subdivided locating accuracy when using centioid algorithm. In this paper  we have analyzed all pixel geometrical characteristics influence on the star position accuracy. From simulation experiments  we can conclude that Fill factor and pixel geometric shape influence on star position accuracy. The star locating error increased when Fill Factor decreased  and different geometrical shape of active sensitive area of pixel can make different influence on star location accuracy  the symmetrical sensitive area in x or y axis have symmetrical location error in the same axis.