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Structural amelioration of 920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL) (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Energy, Environment and Sustainable Development, EESD 2012, October 12, 2012 - October 14, 2012, Jilin, China
作者:  
Liu Y.;  Liu Y.;  Wang L.;  Wang L.;  Wang L.
收藏  |  浏览/下载:18/0  |  提交时间:2013/03/25
920 nm optically pumped semiconductor vertical external-cavity surface emitting laser (OPS-VECSEL) has an important application in laser display. We constructed and optimized a 920 nm OPS-VECSEL with active region of In0.09Ga0.91As quantum well (QW) system pumped by 808 nm laser diode module. By the finite element method  self-consistent solutions of the semiconductor electronic and optical equations are realized to calculate the characteristics parameters of OPS-VECSEL. The performances of device especially the mode  the threshold and the optical-optical translation efficiency were analyzed by dealing with different number of QWs (1  2 and 3) in one period  QW depth  barrier width  the component and dimension of the non-absorption layer. We chose an improved structure of them. On this basis  we ameliorated the number of QW periods and the simulation showed that in order to obtain high performance device  the choice of the number of QW periods must be cautious. (2013) Trans Tech Publications  Switzerland.  
Optimization of the two parameters of classical blaze grating in Littrow mount (EI CONFERENCE) 会议论文  OAI收割
2nd International Conference on Advanced Engineering Materials and Technology, AEMT 2012, July 6, 2012 - July 8, 2012, Zhuhai, China
作者:  
Zhang S.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
Parameter optimization of passive dynamic walking biped with knees (EI CONFERENCE) 会议论文  OAI收割
2012 2nd International Conference on Materials Science and Information Technology, MSIT 2012, August 24, 2012 - August 26, 2012, Xi'an, Shaan, China
作者:  
Zhang P.
收藏  |  浏览/下载:21/0  |  提交时间:2013/03/25
A method to find the optimized parameter values of passive dynamic walking biped is presented. The effects of biped physical parameters on the stability property of passive gaits are studied by simulation experiments. The chosen parameters include the mass distribution  length of leg and slope angle. The stability property of passive walking limit cycles is used as criterion of optimization calculation  including the orbital stability described by eigen-values of linearized Poincare map and the global property described by size of attraction region. The simulation results show how the stability of limit cycle varies when physical parameters of the passive biped change. The work is useful to explore the inherent property of passive dynamic walking and can be used as an important instruction in the mechanical design of biped robots based on principle of passive dynamic walking. (2012) Trans Tech Publications  Switzerland.  
Determination of optimum process parameters in gas-assisted injection molding (EI CONFERENCE) 会议论文  OAI收割
2011 International Conference on Electrical Information and Mechatronics, ICEIM2011, December 23, 2011 - December 25, 2011, Jiaozuo, China
Zi K.; Chen L.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
With finite element analysis software Moldflow  numerical simulation and studies about FM truck roof handle were conducted on gas-assisted injection molding process. The influences of melt pre-injection shot  gas pressure  delay time and melt temperature were observed by using multi-factor orthogonal experimental method. According to the analysis of the factors' impact on evaluation index  the optimized parameter combination is obtained. Therefore the optimization design of technological parameters is done. The results show that during the gas-assisted injection molding  optimum pre-injection shot is 94%  gas pressure is 15MPa  delay time is 0.5s  melt temperature is 240 C. This study provided a more practical approach for the gas-assisted injection molding process optimization.  
Optimum design of the carbon fiber thin-walled baffle for the space-based camera (EI CONFERENCE) 会议论文  OAI收割
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:13/0  |  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.  
Three-sample rotation vector algorithm with angular rate input (EI CONFERENCE) 会议论文  OAI收割
2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China
作者:  
Zhang Y.
收藏  |  浏览/下载:20/0  |  提交时间:2013/03/25
In order to research the attitude algorithm with angular rate input under the conical motion  a optimal threesample rotation vector algorithm based on single-step Newton backward interpolation is proposed. Using the principle of limited rigid body rotation and the characteristic of angular rate input  three-sample rotation vector algorithm is derivated. To minimum attitude errors  three-sample rotation vector algorithm is optimized. Three angular rate extraction methods of singlestep entire sample recursion  multi-step entire sample and singlestep Newton backward interpolation are proposed. Under the condition of conical motion with semi-cone angle 3 and angular frequency 2rad/s  simulation is done. The simulation results show that single-step Newton backward interpolation is superior to the other two methods  and its maximum error peak is 0.01  error drift rate is 0.036/h. Experiments in three-axis flying turntable with the same parameters are carried out  and the results show that error drift rates of three-channels are less than those of traditional quaternion  which are 13.53%  12.08% and 23.68% lower respectively. It also verified that the new algorithm can perform a high accuracy under the conical motion. 2011 IEEE.  
The layout parameters of well groups and effect on land subsidence for salt mine in Zhangshu tourist area 会议论文  OAI收割
Beijing, PEOPLES R CHINA, OCT 26-29, 2011
作者:  
Yao Yuanfeng;  Yang Chunhe;  Li Yinping;  Ji Wendong
  |  收藏  |  浏览/下载:22/0  |  提交时间:2018/06/05
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:39/0  |  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.  
Optimization procedure for design of heliostat field layout of a 1MWe solar tower thermal power plant (EI CONFERENCE) 会议论文  OAI收割
Solid State Lighting and Solar Energy Technologies, November 12, 2007 - November 14, 2007, Beijing, China
作者:  
Zhang H.;  Zhang H.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
A procedure for designing and optimizing heliostat field layout of solar tower thermal power plant is developed. The ray tracing is used for the calculation of the optical efficiency of field. The mathematical theory of the calculation is derived. The parametric search algorithm  which allows variation of the field parameters within a specified range  is used for the optimization of field. The field layout is made automatically according to the no-blocking loss condition and the heliostats are located at the positions where the annual incident cosine value is higher. In this way  the blocking and cosine losses are lowered. Because the optimization of the distance between fore-and-aft two rows of heliostat is avoided  the computer time is reduced effectively. Using this procedure the heliostat field of a 1MWe solar tower power plant was designed. Four modes of layout including North-South cornfield  North-South stagger  Radial cornfield and Radial stagger were experimented and optimized respectively. The comparison of the field efficiency for the four optimized results was made. It is concluded that the North-South cornfield layout is the optimal decision for the 1MWe solar tower power plant.  
Geometry parameter optimization of large cross-sectional S-shaped bent rib waveguides for silicon based optical switches 期刊论文  OAI收割
chinese physics letters, 2007, 卷号: 24, 期号: 3, 页码: 744-746
Li ZY (Li Zhi-Yong); Liu JW (Liu Jing-Wei); Yu JZ (Yu Jin-Zhong)
收藏  |  浏览/下载:109/0  |  提交时间:2010/03/29