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浏览/检索结果: 共11条，第1-10条 帮助 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 Mechanical behavior analysis on electrostatically actuated rectangular microplates 期刊论文 JOURNAL OF MICROMECHANICS AND MICROENGINEERING, 2015, 卷号: 25, 期号: [db:dc_citation_issue] 作者:  Li, Zhikang;  Zhao, Libo;  Jiang, Zhuangde;  Ye, Zhiying;  Dai, Lu 收藏  |  浏览/下载：10/0  |  提交时间：2019/12/02 a new reduced-order model  static deflection analysis  electrostatically actuated rectangular microplates  pull-in voltage prediction  explicit expressions  capacitance calculation   Design of motion adjusting system for space camera based on ultrasonic motor (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 Xu K.; Jin G.; Gu S.; Yan Y.; Sun Z. 收藏  |  浏览/下载：74/0  |  提交时间：2013/03/25 Drift angle is a transverse intersection angle of vector of image motion of the space camera. Adjusting the angle could reduce the influence on image quality. Ultrasonic motor (USM) is a new type of actuator using ultrasonic wave stimulated by piezoelectric ceramics. They have many advantages in comparison with conventional electromagnetic motors. In this paper  some improvement was designed for control system of drift adjusting mechanism. Based on ultrasonic motor T-60 was designed the drift adjusting system  which is composed of the drift adjusting mechanical frame  the ultrasonic motor  the driver of Ultrasonic Motor  the photoelectric encoder and the drift adjusting controller. The TMS320F28335 DSP was adopted as the calculation and control processor  photoelectric encoder was used as sensor of position closed loop system and the voltage driving circuit designed as generator of ultrasonic wave. It was built the mathematic model of drive circuit of the ultrasonic motor T-60 using matlab modules. In order to verify the validity of the drift adjusting system  was introduced the source of the disturbance  and made simulation analysis. It designed the control systems of motor drive for drift adjusting system with the improved PID control. The drift angle adjusting system has such advantages as the small space  simple configuration  high position control precision  fine repeatability  self locking property and low powers. It showed that the system could accomplish the mission of drift angle adjusting excellent. 2011 SPIE.   The new approach for infrared target tracking based on the particle filter algorithm (EI CONFERENCE) 会议论文 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China Sun H.; Han H.-X. 收藏  |  浏览/下载：50/0  |  提交时间：2013/03/25 Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring  precision  and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection  the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure  but in order to capture the change of the state space  it need a certain amount of particles to ensure samples is enough  and this number will increase in accompany with dimension and increase exponentially  this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining"  we expand the classic Mean Shift tracking framework.Based on the previous perspective  we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis  Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism  used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation  and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information  this approach also inhibit interference from the background  ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).   Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China Zhang B.; Zhang Z.-D.; Zhang S.-M. 收藏  |  浏览/下载：34/0  |  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).   In-situ self-monitoring of latent image in fabrication of holographic gratings 期刊论文 2010, 2010 Zhao Jinsong; Li Lifeng; Wu Zhenhua 收藏  |  浏览/下载：2/0 Research on the the device of non-angular vibration for opto-electronic platform (EI CONFERENCE) 会议论文 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Smart Structures and Materials in Manufacturing and Testing, April 26, 2010 - April 29, 2010, Dalian, China An Y.; Song C.-P.; Kuang R.-J.; Jin G. 收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25 The opto-electronic platform is the main equipment for aviation reconnaissance. It is a surveillance system with the function of search  recognition orientation and tracking by opto- electronic instruments. It is made up of opto-electronic instruments which are used to get high quality image  and stabilization tracking system to control stabilization and gesture of platform for exact tracking. The opto-electronic platform purpose is to achieve high quality image. Besides the impact of optic system  the image quality of the system is influenced greatly in the vibration environment. The research worked by Zhao peng which demonstrated the affection caused by angular vibration was worse than which caused by line vibration  and what was multiplied direct ratio with plane altitude. So it is necessary to design a new device which could be used widely and has good angular vibration isolation effect. According to the theory of parallelogram  the non-angular vibration device had been designed with spatial links  and the theory of non-angular vibration was analyzed. The three-dimensional model was set with UG  the analysis was done by ADAMS/vibration software. The acceleration and displacement response of the device in each direction was calculated by inspiriting it with sine wave of the acceleration in three directions  and the stiffness and damp were studied. All the work prove the design principle of the device is reasonable  and the device is adopted to keep the platform motion moving horizontally  at the meantime the device is good at isolating vibration in all directions. 2010 SPIE.   Analysis model of X-ray coherent scatter images (EI CONFERENCE) 会议论文 3rd International Conference on BioMedical Engineering and Informatics, BMEI 2010, October 16, 2010 - October 18, 2010, Yantai, China Liu T.; Liu J.; Li Y.; Qiao S.; Song J. 收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25 X-ray coherent scatter imaging with diagnostic equipment is feasible. The energy distribution extracting from image is a way to get information hidden in images. In this paper  a new analysis model of x-ray scatter images was presented. With the model some situations of real coherent scatter image affected by noise  eccentricity and energy distribution were simulated. The result shows that the clinical x-ray coherent scatter can be simulated well by a Gauss distribution model. And an inner correlation algorithm was discussed to help calculate center approaching the theory center with the model. 2010 IEEE.   Dome design and coupled thermal-mechanical analysis of supersonic missile (EI CONFERENCE) 会议论文 2009 International Conference on Optical Instruments and Technology, OIT 2009, October 19, 2009 - October 22, 2009, Shanghai, China Xing-qiao A.; Qun W.; Hong-guang J. 收藏  |  浏览/下载：40/0  |  提交时间：2013/03/25 A review of high-speed flow pressure and aerodynamic heating effect on Supersonic missile's dome is given. The dome should have excellent properties in optical  mechanical and chemical characteristics. A design of dome on supersonic mode is described according to tactical guide line of a missile. The dome made of quartz which is about 8mm thick and 141mm in window diameter. To check up the reliability of the dome  a reasonable finite element model (FEM) of dome is established  and a thermal-mechanical Analysis to the dome by finite element software NASTRAN has carried on  through these can obtained the distribution of temperature field and stress field when the speed is 2.3Ma. The results indicated that the stress was concentrated in the joint of the dome end and the Missile Section  and the maximum stress was 16.4Mpa. The stress of other nodes was smaller than the allowable stress of quartz glass. Reference to the results of the analysis  a lightweight revision to the dome structural dimension and a new method of dome fixing have put forward  which can reduce the stress concentration. 2009 SPIE.   构建非寿险公司承保盈利能力分析新模式 学位论文 2009, 2008 李群 收藏  |  浏览/下载：1/0  |  提交时间：2016/02/14 非寿险公司  承保盈利能力  分析新模式  non-life insurance companies  profitability in underwriting  a new analysis model   Modeling diffractive optical elements in hybrid systems with the effect of the material dispersion (EI CONFERENCE) 会议论文 Current Developments in Lens Design and Optical Engineering IX, August 11, 2008 - August 12, 2008, San Diego, CA, United states Zhang H.; Liu H.; Lu Z.; Zhang H.; Ni Z. 收藏  |  浏览/下载：9/0  |  提交时间：2013/03/25 The diffractive optical element (DOE) is always modeled as an ideal pure diffractive element which neglects the refractive dispersion of the element's material. In this paper  a new model of the diffractive optical element is proposed  in which the effect of the refractive dispersion of the DOE's material is considered. The new model is explained and compared with standard diffraction-order expansion with the help of a hybrid system example. The analytical results show that the new model has an important meaning for the exact analysis of the hybrid refractive-diffractive optical system. 2008 Copyright SPIE - The International Society for Optical Engineering.