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	Analysis of zenith pass problem and tracking strategy design for roll-pitch seeker (EI CONFERENCE) 会议论文 OAI收割作者: Jiang H. 收藏 \| 浏览/下载：22/0 \| 提交时间：2013/03/25 Roll-pitch seeker is currently applied in particular missiles. There is a stubborn problem called zenith pass problem while roll-pitch seeker is used. Analysis of the zenith pass problem which always results in loss of target is presented in this paper. Based on the analysis result tracking strategy is carried out to deal with zenith pass problem. To prove the validity of tracking strategy a practical roll-pitch seeker was accomplished. Model identification and common PID controllers for the physical roll-pitch seeker are taken on after that both disadvantages derived from zenith pass problem in tracking process and meliorated phenomenons by the tracking strategy are shown. It is concluded that the tracking strategy designed for solving the zenith pass problem is efficient. 2011 Elsevier Masson SAS. All rights reserved.
	Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文 OAI收割 2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China 作者: Zhang L.; Zhang L. 收藏 \| 浏览/下载：69/0 \| 提交时间：2013/03/25 The coaxial two-mirror telescope consists of two mirrors facing each other. Classical two-mirror arrangements are Gregorian and Cassegrain. These systems are usually applied to space telescopes and often have optical baffles to prevent stray light from entering the focal plane. The optical baffles consist of concentric rings suspended between the secondary and the primary mirror. The secondary baffle for a large two-mirror optical system is designed and analyzed in this paper. According to mission of a telescope the structure should have high stiffness and high reliability and light weight. Compared with invar aluminum alloy and titanium alloy carbon fiber composite is currently the best material in terms of weight-to-strength ratio. It also has advantages of high temperature tolerance and low thermal expansion. So carbon fiber composite is chosen as material to meet requirements of the coaxial telescope. In this paper optimization method based on finite element analysis (FEA) is used for design the secondary baffle. Minimum weight of the baffle is chosen as an objective function. Thicknesses of former tube and vanes are chosen as variables. Analysis results show that the designed secondary baffle has maximum diameter of 180mm total length of 120mm and weighs 142g. And its fundamental frequency reaches 651Hz. Therefore the baffle has many advantages such as ultra-light weight high stiffness and dimensional stability etc. The optimization method and the baffle design can be helpful to other coaxial telescopes such as Cassegrain Gregorian and their subdivisions. 2012 IEEE.
	The sequence measurement system of the IR camera (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 H.-B.; Han H.-X.; Geng A.-H. 收藏 \| 浏览/下载：39/0 \| 提交时间：2013/03/25 Currently the IR cameras are broadly used in the optic-electronic tracking optic-electronic measuring fire control and optic-electronic countermeasure field but the output sequence of the most presently applied IR cameras in the project is complex and the giving sequence documents from the leave factory are not detailed. Aiming at the requirement that the continuous image transmission and image procession system need the detailed sequence of the IR cameras the sequence measurement system of the IR camera is designed and the detailed sequence measurement way of the applied IR camera is carried out. The FPGA programming combined with the SignalTap online observation way has been applied in the sequence measurement system and the precise sequence of the IR camera's output signal has been achieved the detailed document of the IR camera has been supplied to the continuous image transmission system image processing system and etc. The sequence measurement system of the IR camera includes CameraLink input interface part LVDS input interface part FPGA part CameraLink output interface part and etc thereinto the FPGA part is the key composed part in the sequence measurement system. Both the video signal of the CmaeraLink style and the video signal of LVDS style can be accepted by the sequence measurement system and because the image processing card and image memory card always use the CameraLink interface as its input interface style the output signal style of the sequence measurement system has been designed into CameraLink interface. The sequence measurement system does the IR camera's sequence measurement work and meanwhile does the interface transmission work to some cameras. Inside the FPGA of the sequence measurement system the sequence measurement program the pixel clock modification the SignalTap file configuration and the SignalTap online observation has been integrated to realize the precise measurement to the IR camera. Te sequence measurement program written by the verilog language combining the SignalTap tool on line observation can count the line numbers in one frame pixel numbers in one line and meanwhile account the line offset and row offset of the image. Aiming at the complex sequence of the IR camera's output signal the sequence measurement system of the IR camera accurately measures the sequence of the project applied camera supplies the detailed sequence document to the continuous system such as image processing system and image transmission system and gives out the concrete parameters of the fval lval pixclk line offset and row offset. The experiment shows that the sequence measurement system of the IR camera can get the precise sequence measurement result and works stably laying foundation for the continuous system. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).
	Brazing RB-SiC used in large aperture space optical system (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Materials and Products Manufacturing Technology, ICMPMT 2011, October 28, 2011 - October 30, 2011, Chengdu, China Zhang B.; Zhang Z. 收藏 \| 浏览/下载：26/0 \| 提交时间：2013/03/25 Because of the sic material's superior optical characteristic machine characteristic and hot characteristic it becomes currently the space big aperture reflector choose firstly1. For larger aperture sic mirror it is not economical and safe to make the monolithic body directly 2 3. The SiC mirror brazed assembly with several segments can solve these problems. In this paper one 600 mm sic plane mirror as demonstration welded with 3 radial segments is roughly grinded to the required figure at first then the mirror is finely grinded and polished by the technology of CCOS the mirror figure error is less than 1/20 ( = 632.8nm) in RMS finally. The problems of the preferential removal near braze joint are solved. The methods of reducing the residual stress of mirror are discussed. At last some measurements and experiments are carried on and the results conclude that the brazed SiC mirror can meet the requirement of large aperture optical systems. (2011) Trans Tech Publications.
	Research of new wireless sensor network protocol: ZigBee RF4CE (EI CONFERENCE) 会议论文 OAI收割 International Conference on Electrical and Control Engineering, ICECE 2010, June 26, 2010 - June 28, 2010, Wuhan, China 作者: Xu Z.-J.; Li D. 收藏 \| 浏览/下载：19/0 \| 提交时间：2013/03/25 Currently most existing remote controls for consumer electronics use infrared remotes (IR) technology to control devices which Increases the demand for advanced functionality that cannot be supported by existing IR. RF remotes provide new levels of interactivity and convenience for today's digital home when compared to IR remotes. New network protocols: ZigBee RF4CE are helping to make this technology accessible to us. In this paper we first introduce the architecture and primitives of the ZigBee RF4CE node initialization service then present the researches of the Application layer and Network layer respectively. Focusing on the functions of Network layer including: frequency usage service transmission control service discovery service power saving service pairing service and security service. 2010 IEEE.
	Athermalization of coaxial reflective space telescope (EI CONFERENCE) 会议论文 OAI收割 5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, April 26, 2010 - April 29, 2010, Dalian, China Lei Z.; Guang J. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 This paper focuses on thermal effects which caused by environmental temperature changes on coaxial reflective space telescope and its solution. Curvature radius and center thickness of optical elements and the space distance between optical elements may be changed by thermal effects. And the optical performance of the telescope may be impacted. Based on the analysis of thermal effects on coaxial reflective space telescope athermalized design techniques are emphatically presented the advantages and the disadvantages of the three athermalizations used currently are compared in the paper. The feasibility and effectiveness are verified by an example of a cassegrain space telescope. 2010 Copyright SPIE - The International Society for Optical Engineering.
	Geometrical modulation transfer function of different active pixel of CMOS APS (EI CONFERENCE) 会议论文 OAI收割 2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 2, 2005 - November 5, 2005, Zian, China 作者: Li J.; Liu J.; Liu J.; Liu J.; Li J. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 The geometrical Modulation Transfer Function (MTF) of CMOS APS (active pixel sensor) is analyzed in this paper. Advanced APS have been designed and fabricated where different pixel shapes such as square rectangle and L shape were placed because the amplifier circuit and other function circuits inter pixel of APS take up some pixel area. MTF is an important figure of merit in focal plane array imaging sensors. Research on analyzing the MTF for the proper pixel shape is currently in progress for a centroidal configuration of a target position. MTF will give us a more complete understanding of the tradeoffs opposed by the different pixel designs and by the signal processing conditions. Based on image sensor sampling and reconstructing model the MTF expression of any active pixel shape has been deduced in this paper. According to actual pixel shape three different active area pixels were analyzed they were square rectangle and L shape their Fill Factor (FF) is 30% 44% and 55% respectively. Results of simulation experiments indicate that different pixel geometrical characteristics contribute significantly to the figures of their MTF. Different geometrical shape of active sensitive area of pixel and different station in pixel would influence MTF figures. The analysis results are important in designing better APS pixel and more important in analyzing imaging system performance of APS subpixel precision system.
	Development of a new diffuse near infrared food measuring (EI CONFERENCE) 会议论文 OAI收割 Sitxh International Symposium on Instrumentation and Control Technology: Signal Analysis, Measurement Theory, Photo-Electronic Technology, and Artificial Intelligence, October 13, 2006 - October 15, 2006, Beijing, China 作者: Zhang J.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：33/0 \| 提交时间：2013/03/25 Industries from agriculture to petrochemistry have found near infrared (NIR) spectroscopic analysis useful for quality control and quantitative analysis of materials and products. The general chemical polymer chemistry petrochemistry agriculture food and textile industries are currently using NIR spectroscopic methods for analysis. In this study we developed a new sort NIR instrument for food measuring. The instrument consists of a light source 12 filters to the prismatic part. The special part is that we use a mirror to get two beams of light. And two PbS detectors were used. One detector collected the radiation of one light beam directly and the value was set as the standard instead the standard white surface. Another light beam irradiate the sample surface and the diffuse light was collected by another detector. The value of the two detectors was compared and the absorbency was computed. We tested the performance of the NIR instrument in determining the protein and fat content of milk powder. The calibration showed the accuracy of the instrument in practice.
	Integrated optical amplifiers based on rare-earth doped (red) oxide glasses (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photonic Glass (ISPG 2002), October 14, 2002 - October 17, 2002, Shanghai, China 作者: Chen B.; Chen B. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 Oxide glasses have been used since long time to host a number of active compounds first of all rare-earth (RE) ions for lasing. Recently the advantages offered by guided-wave format namely the small size the high pump power density and the larger flexibility in design and fabrication led to the development of fiber lasers and amplifiers based on Er3+-doped glasses. Currently a growing activity is aimed at achieving large optical gain in Er3+-doped planar waveguides having in mind the single-chip realization of integrated optical amplifiers and lasers. The aim of the present paper is to provide a quick overview of this area and to briefly discuss possible future developments.