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Chinese Academy of Sciences Institutional Repositories Grid
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CF-Targeter: A Rational Biological Cell Factory Targeting Platform for Biosynthetic Target Chemicals 期刊论文  OAI收割
ACS SYNTHETIC BIOLOGY, 2019, 卷号: 8, 期号: 10, 页码: 2280-2286
作者:  
Ding, Shaozhen;  Cai, Pengli;  Zhang, Dachuan;  Cheng, Xingxiang;  Sun, Dandan
  |  收藏  |  浏览/下载:13/0  |  提交时间:2020/12/09
Systemic Wound Healing Associated with local subCutaneous Mechanical Stimulation (vol 6, 39043, 2017) 期刊论文  OAI收割
SCIENTIFIC REPORTS, 2017, 卷号: 7, 期号: -, 页码: 46118
作者:  
Nardini, Christine;  Devescovi, Valentina;  Liu, Yuanhua;  Zhou, Xiaoyuan;  Lu, Youtao
  |  收藏  |  浏览/下载:36/0  |  提交时间:2020/12/09
Effect of design parameters on the reduction of top piston ring friction (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Computer-Aided Design, Manufacturing, Modeling and Simulation, CDMMS 2012, September 21, 2012 - September 23, 2012, Chongqing, China
作者:  
Wang P.
收藏  |  浏览/下载:138/0  |  提交时间:2013/03/25
Design of a miniature axial flux flywheel motor with PCB winding for nanosatellites (EI CONFERENCE) 会议论文  OAI收割
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
Wu J.
收藏  |  浏览/下载:41/0  |  提交时间:2013/03/25
This paper presents the design and analysis of an axial flux permanent-magnet (AFPM) machine for nanosatellites application. It is a miniature axial flux surface mounted permanent magnet flywheel motor  using a printed circuit board (PCB) stator winding. The PCB stator has simplified the design and construction and avoids unnecessary space  since size reduction has become one of the most important aspects of flywheel motor design for nanosatellites. The performances of the machine are estimated by combination method of three-dimensional (3D) electromagnetic finite element analysis (FEA) and approximate theoretical analysis. The back EMF and electromagnetic torque are derived. A comparison between the analysis and experimental measurement results of the prototype machine is also presented. Both simulated and experimental results show that the proposed motor would be an acceptable solution for the nanosatellite applications with advantages such as simple structure and low-cost  as multi-layer circuit board production techniques have made the production of printed circuit coils cheaper and easier. 2012 IEEE.  
Surface shape optimization for the space membrane reflector (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011, August 12, 2011 - August 14, 2011, Harbin, China
作者:  
Zhang Y.;  Zhang P.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
Space membrane reflector is very promised for optical quality application with the merits of ultra-lightweight and flexible. In order to improve the surface precision of membrane reflectors  the formation and surface shape error of a membrane at uniform load are studied based on the henky-cambell equations of circular membrane. The ANSYS software is used to build an optimization model of membrane reflector surface shape  in which the yield strength is the state variable  the surface load on ten concentric annular regions of the mirror is the design variable  and the minimum RMS between ideal surface and mirror surface is the target function. and the theoretical and experimental result show that RMS and PV of the optimized surfaces are reduced respectively than those before optimization. In a word  this paper offers the theoretical and experimental basis of the polyimide membrane reflector. 2011 IEEE.  
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:49/0  |  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).  
Effect of gimbal point displacement on optical axis pointing precision in an image seeker (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:39/0  |  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.  
Dynamic coupling analysis and modeling for stabilized platform of rolling-pitching seeker (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
作者:  
Liu H.;  Liu H.;  Liu H.
收藏  |  浏览/下载:13/0  |  提交时间:2013/03/25
Missile's attitude change will be delivered to visual axis through stabilized platform during maneuvering flight  and the missile vibration will be an interference source to visual axis stabilization. In order to solve this problem  the coupling relationship between missile attitude and visual axis is obtained by Coordinate transformation. When the seeker stably tracks a target  the angular velocity of visual axis in inertial space is zero  so the relative angular velocity of roll axis and pitch axis can be derived for servo control. According to Oura dynamics equation  the dynamic models of roll axis and pitch axis were established and kinetic equations of two axises were obtained. The dynamic models can provide theoretical basis to developing research of servo control system and structural optimization design of stabilized platform. Finally  some measures could reduce the dynamic coupling between the framework was given. 2011 IEEE.  
Syntheses, Structures of Four New Complexes Constructed by Flexible Pyridine Ligand and the Relationship Between Conformations and Structures 期刊论文  OAI收割
Chemical Journal of Chinese Universities-Chinese, 2010, 卷号: 31, 期号: 5, 页码: 867-873
C. C. Ji, Z. J. Xu, J. Li, G. X. Liu and H. G. Zheng
收藏  |  浏览/下载:17/0  |  提交时间:2012/11/02
Thermal difference analysis and athermalization design of infrared optical system (EI CONFERENCE) 会议论文  OAI收割
Optical Design and Testing IV, October 18, 2010 - October 20, 2010, Beijing, China
作者:  
Zhang X.;  Zhang X.;  Zhang X.
收藏  |  浏览/下载:32/0  |  提交时间:2013/03/25
When infrared optical system works in a large temperature range  the thermal effect of optical lens and optical tube will produce image plane shift and lead to imaging quality deterioration. In order to eliminate the thermal aberration  the athermalization design principles of infrared optical system were introduced  and some commonly used methods of thermal difference compensation were described. Proceeding from single lens  the thermal difference caused by temperature changing was analyzed  and the relationship between temperature and focus shift was obtained. Considering optical tube thermal expansion  a set of equations to estimate the thermal difference of lens group was given. Finally  an infrared optical imaging system that can work under the temperature range of -40C to 60C was design according to athermal technique  in which a new mechanical passive temperature compensation was proposed. Through simulation  the athermalization design could make imaging plane shift the smallest. The simulation results coincided with the theoretical formula  and the design had reference value in engineering. 2010 Copyright SPIE - The International Society for Optical Engineering.