中国科学院机构知识库网格系统: 检索

Numerical investigation of the starting process in a long-test-duration hypersonic shock tunnel 会议论文 OAI收割
22nd AIAA Computational Fluid Dynamics Conference, 2015, Dallas, TX, United states, June 22, 2015 - June 26, 2015
作者: Wang YP(汪运鹏); Hu ZM(胡宗民); Liu YF(刘云峰); Jiang ZL(姜宗林)

收藏 | 浏览/下载：32/0 | 提交时间：2017/05/05

Inviscid flows Numerical investigations Outlet diameters Reflected shock waves Simulated results Starting process Transmitted shock Unsteady nozzle flow

Analysis on failure mechanism of scarf joints with brittleductile adhesives subjected to uniaxial tensile loads 会议论文 OAI收割
San Diego, CA, United states, November 15, 2013 - November 21, 2013
作者: Liao LJ(廖丽娟); Sawa T; Huang CG(黄晨光)

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收藏 | 浏览/下载：31/0 | 提交时间：2018/11/08

Adhesives Numerical methods Safety engineering Tensile stress Cohesive zone model Ductile adhesives Ductile properties Failure mechanism Load bearing capacity Load displacement curve Simulated results Tensile displacement

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：44/0 | 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.

Experiments and finite element simulations on micro-milling of aluminium alloy7050-T7451 (EI CONFERENCE) 会议论文 OAI收割
10th Asia-Pacific Conference on Materials Processing, APCMP 2012, June 14, 2012 - June 17, 2012, Jinan, China
作者: Li J.; Li J.; Li J.; Zhou J.; Wang F.

收藏 | 浏览/下载：39/0 | 提交时间：2013/03/25

The mechanism of micro-milling modeling for aluminum alloy 7050-T745 is to be investigated and a finite element model for micro-milling that reflects the actual state of the three-dimensional micro-milling is built by adopting the software of ABAQUS/Explicit. Experiment is conducted to verify the validation of the model. Simulated chip morphology in different cutting parameters agrees to the experimental results very well. Based on the FE model cutting stresses equivalent plastic strains temperatures distribution and cutting forces are obtained and analyzed. This provides a good method to investigate the micro milling principles. (2012) Trans Tech Publications.

Design and simulation of CMOS star sensor lens with large relative aperture and wide field (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
Zhong X.; Jin G.

收藏 | 浏览/下载：64/0 | 提交时间：2013/03/25

A 50mm focal length F/1.25 Gaussian type optical system is designed in this paper which has 20field of view. Actual star image adding optical cross-talk effect of CMOS(Complementary Metal Oxide Semiconductor) detector is simulated by non-sequential ray tracing in ZEMAX optical design and analysis software to evaluate its performance. The distortion relative to image spot centriod is introduced and calculated by simulated star images which is less than 0.03% of lens in this paper. Thermal adaptability is discussed by opt-mechanic thermal analysis which shows the RMS spot radius of marginal filed changes less than 0.7m under 10C temperature gradient and changes less than 1m during homogeneous temperature changing from 40C to 40C. The results of analyses and simulations show the design of this lens can achieve the requirement of high precision CMOS star sensor well. 2011 IEEE.

Reality Sim: A realistic environment for robot simulation platform of humanoid robot (EI CONFERENCE) 会议论文 OAI收割
5th International Conference on Automation, Robotics and Applications, ICARA 2011, December 6, 2011 - December 8, 2011, Wellington, New zealand
作者: Fu Y.

收藏 | 浏览/下载：42/0 | 提交时间：2013/03/25

As a virtual training testing and evaluating environment simulation platform becomes a significant component in Soccer Robot project. Nevertheless the simulated environment in a simulation platform usually has a big gap with the realistic world. In order to solve this issue we demonstrate a more realistic simulation system which is called Reality Sim with numerous real images. By this system the computer vision code could be easily tested on simulation platform. For this purpose previously an image database with a large quantity of images recorded by camera pose is built. Furthermore if the camera pose of an image is not included in the database an interpolation algorithm is used to reconstruct a brand-new realistic image of that pose such that a realistic image could be provided on every robot camera pose. Our results show this system effectively simulates a more realistic environment for simulation platform. 2011 IEEE.

High precision test method for dynamic imaging of space camera (EI CONFERENCE) 会议论文 OAI收割
2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States
作者: Jin L.-X.; Zhang K.; Zhang K.; Zhang K.; Zhang K.

收藏 | 浏览/下载：36/0 | 提交时间：2013/03/25

A test method for dynamic imaging of space TDICCD (Time Delay and Integration Charge Coupled Devices) camera was presented in this paper. The test method adopted the PLL (Phase Locked Loop) technology and CMAC (Cerebella Model Articulation Controller) friction compensation as control strategy. Furthermore According to this method a test system for dynamic imaging of space TDICCD camera was designed and implemented. The system simulated the movement of the ground objects relative to the space aerocraft to validate the capability of image speed match and the dynamic imaging quality of TDICCD camera. The design adopted a precision turntable and a drift turntable to simulate the movement around the earth and the drift motion in different latitude due to the rotation of earth of the aerocraft. The turntables were drived by permanent magnet torque motor which was powered by PWM (Pulse Width Modulation). The system adopted DSP (Digital Signal Processor) as the control core and reached a very high performance. The experimental results showed that the steady speed error was better than 0.01 % and the instantaneous speed error reached 0.0267%. The precision of the test system designed met the requirement for dynamic imaging of TDICCD camera. 2010 IEEE.

Novel method for optimizing polishing tool-path in CCOS based on weighted-iterative algorithm (EI CONFERENCE) 会议论文 OAI收割
4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China
作者: Zhang X.-J.; Wang X.; Wang X.; Wang X.; Wang X.-K.

收藏 | 浏览/下载：47/0 | 提交时间：2013/03/25

In Computer Controlled Optical Surfacing (CCOS) polishing tool-path is the base of solving other control parameters such as dwell time. In order to improve the fabrication results of polishing off-axis aspheric a novel method to optimize the tool-path is discussed in this paper. The optimizing method named weighted-iterative algorithm is according to the balance principle of the particle system. The power factor of each dwell point represents the requirement of dwell density. Considering the factors which influence the polishing result the power factors cosist of three elements include constant error distribution and dwell distance of workpiece edge. The tool-path is solved by numerical iterative method. In the end an error data is simulated with actual parameters using the matrix-based algorithm with two different tool-paths. The one is X-Y uniform spacing model and the other one is to optimize it based on the first. The comparison shows that the results of the optimized one are much better than traditional one especially the rms convergence rate. Theory of the algorithm is simple and exercisable and it satisfies practical requirement as well. 2009 SPIE.

Equivalent lenses of supersonic seeker's outflow refractive index field obtained by simulation and experiment (EI CONFERENCE) 会议论文 OAI收割
2008 International Conference on Optical Instruments and Technology: Optical Systems and Optoelectronic Instruments, November 16, 2008 - November 19, 2008, Beijing, China
Qun W.; Hongguang J.; Ming X.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

In order to decrease the aerodynamic drag of supersonic image guide missile and design a non-spherical dome the outflow field of the missile's dome is simulated using FLUENT. Based on the simulated results the accurate density field of the outflow field at all kinds of flight conditions is obtained and then the refractive index field of the outflow field is gotten according to the Gladstone-Dale law. The results show that the shock wave induces the heterogeneity of the refractive index field and the turbulent causes distortion. The outflow field is divided into several zones which are taken as equivalent lenses for aberration analysis. 2009 SPIE.

Contrast research on interpolation and subpixel imaging in CCD geometric superresolution reconstruction (EI CONFERENCE) 会议论文 OAI收割
1st Asia Pacific Conference on Postgraduate Research in Microelectronics and Electronics, PrimeAsia 2009, November 19, 2009 - November 21, 2009, Shanghai, China
作者: Xu Y.-S.; Yang S.-W.

收藏 | 浏览/下载：28/0 | 提交时间：2013/03/25

In order to enhance the resolution of Charge Coupled Device (CCD) pixel with the pixel dimension and focal length of optical system unchanged the problem of CCD geometric superresolution is educed. The problem is discussed in terms of software and hardware. In software the bicubic interpolation is introduced while in hardware the subpixel imaging method is utilized. The subpixel imaging method integrates two uniform linear CCDs staggered by half dimension of pixel in one device. In operation the line frequency is doubled. At last the collected data is interweaved to synthesize a high resolution image. The two methods bicubic interpolation and subpixel imaging are simulated with Matlab7.0.1. The qualitative and quantitative analyses are given. The simulated results of lanczos and cubic spline interpolation methods are given simultaneously to show the performance of interpolation. The simulation result shows that the result images quality becomes better in both methods but compared with bicubic interpolation method the synthesized image PSNR gained from sub-pixel imaging is averagely enhanced by 2.1682dB while the elapsed time is reduced to be about one forth. The subpixel imaging method could significantly mitigate the image blur introduced by undersample. 2009 IEEE.