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Stray light analysis of solar photoelectric detection system on space target (EI CONFERENCE) 会议论文
2012 International Conference on Intelligent System and Applied Material, GSAM 2012, January 13, 2012 - January 15, 2012, Taiyuan, Shanxi, China
Li L.-Y.; Wang Y.-F.; San X.-G.
收藏  |  浏览/下载：135/0  |  提交时间：2013/03/25
Most conventional spacious solar photoelectric detection systems suffer from unexpected stray light. This paper demonstrates the effects on photoelectric detection system bring out by stray light. On this foundation  build up evaluation index of stray light system  to search the reasonable programme to eliminating stray light. A detailed telescope system geometry model was created  and scatter models were create for telescope and enclosure components. By the means of designing the structure of main baffle  baffle vane and the coating technology. In order to verify the prosperity of structure that designed  we utilizes software to analysis opto-mechanical model. we utilizes software to analysis opto-mechanical model. The simulations show that point source transmittance of the system is thus reduced by up to two orders of magnitude between 10-8 and 10-10. Meanwhile  the experiment obtains clean detection data which satisfies the system requirements. Stray light has been suppressed effectually  and so measurement precision was improved from detection graphics. (2012) Trans Tech Publications.  
Lightweight design of large scale theodolite's turntable based on topology optimization of continuum structure (EI CONFERENCE) 会议论文
2012 International Conference on Optoelectronics and Microelectronics, ICOM 2012, August 23, 2012 - August 25, 2012, Changchun, China
San X.; Wang Y.
收藏  |  浏览/下载：22/0  |  提交时间：2013/03/25
In order to solve the problem that the weight of large scale theodolite's casting or steel plate welded structure is too heavy  lightweight design of large scale turntable based on topology optimization of continuum structure is investigated. Topology optimization could have better optimization efficiency because it can provide the optimized distribution of material and gain optimized structure in conceptual design phase of the structural design. In order to obtain lightweight and high stiffness structure  a truss turntable based on topology optimization of continuum structure is presented  and the validity of this lightweight structure is examined by finite element analysis. Comparing to the traditional welding steel turntable  the lightweight turntable  without changing the static displacement  can lose 386.48 kg(lightweight ratio is 26.7%)  and its first-order natural frequency raises from 167.02Hz to 173.71Hz. Meanwhile  in other aspects this turntable also has better performance than traditional structure. 2012 IEEE.  
Application of adaptive enhancement means in head and neck CR image (EI CONFERENCE) 会议论文
2012 3rd International Conference on Information Technology for Manufacturing Systems, ITMS 2012, September 8, 2012 - September 9, 2012, Qingdao, China
Zhang M.-H.; Zhang Y.-Y.
收藏  |  浏览/下载：26/0  |  提交时间：2013/03/25
Digital CR of head and neck overcomes the disadvantage of regular X-ray radiography  which can not reveal bone and soft tissue position deficiency in one exposing  and reduces the Xray radiation dose. Meanwhile  various factors cause the decline of image quality  and images must be enhanced in order to meet demands of doctor's clinical diagnosis. The general enhancement algorithms don't consider body's structure differences and density characteristics. A new adaptive CR enhancement algorithm was proposed in this article  and head and neck CR images were processed with this method and compared with linear unsharp masking method. The experiment proves that the details of CR image enhanced were abundant and enhanced CR image had good visual effect  SNR was high  as well as detail variance /background variance (DV/BV) indicating that this algorithm is suitable for head and neck CR medical images. (2012) Trans Tech Publications  Switzerland.  
Research on the torque characteristic of disc micromotor on axial magnetic field (EI CONFERENCE) 会议论文
2012 2nd International Conference on Consumer Electronics, Communications and Networks, CECNet 2012, April 21, 2012 - April 23, 2012, Three Gorges, China
Liu B.
收藏  |  浏览/下载：47/0  |  提交时间：2013/03/25
In order to increase the electromagnetic torque density of micromotor with axial magnetic field  numerical analysis of permanent magnetic field and electromagnetic torque were deduced and the key factors of increasing torque density of micromotor was obtained. The numerical analysis of three-dimensional magnetic field in air gap produced by spliced sector permanent magnetic poles is done  and the way of improving flux density and permanent magnet use efficiency are given through investigating the influence of magnet thickness  height of air gap and pole interval rate and other parameters to air gap flux density and leakage flux. Based on the test of axial magnetic field and torque characteristic of micromotor  the analysis of micromotor magnetic field and calculation of torque are verified  meanwhile using the plane stator with 0.7mm thickness assemble micromotor having minimum air gap height of 1mm and its torque constant up to 3.8mNm/A. 2012 IEEE.  
Research on satellite platform vibration compensation technology for space optical communication (EI CONFERENCE) 会议论文
2012 International Meeting on Opto-Electronics Engineering and Materials Research, OEMR 2012, July 27, 2012 - July 29, 2012, Shenyang, Liaoning, China
Han C.; Li X.
收藏  |  浏览/下载：18/0  |  提交时间：2013/03/25
The piezo-electric steering control system is used to compensate the vibration of satellite platform. The mathematical model of piezo-electric steering system is built. The adaptive controller based on improved LMS filter algorithm is designed according to this system characteristic. The adaptive delay filter is designed to solve slow convergence speed problem of traditional algorithm. Meanwhile  the adaptive delay filter can also compensate phase delay of control circuit. The adaptive deviation filter is introduced and it effectively compensates the vibration deviation which is low frequency and high amplitude. The experimental results show that the remained errors are rad  which meets space optical communication requirement and proves that this control scheme is valid and feasible. (2012) Trans Tech Publications  Switzerland.  
The sequence measurement system of the IR camera (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
Geng A.-H.; Han H.-X.; Zhang H.-B.
收藏  |  浏览/下载：31/0  |  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).  
Optimum design of the carbon fiber thin-walled baffle for the space-based camera (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
Yan Y.; Gu S.; An Y.; Jin G.
收藏  |  浏览/下载：11/0  |  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.  
Thermal analysis on supersonic ellipsoidal dome (EI CONFERENCE) 会议论文
2nd International Conference on Multimedia Technology, ICMT 2011, July 26, 2011 - July 28, 2011, Hangzhou, China
Jiang Z.; Wei Q.; Jia H.
收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25
Studied the transient thermal transfer analysis method due to a kind of supersonic ellipsoidal dome  which is a conformal dome. Illuminated the principle of transient thermal transfer analysis. Accomplished the transient thermal analysis based on the model of ellipsoidal dome  and studied the influence about the different material and the different velocity. Considered three materials consist of MgF2  Al2O3  and ZnS  and meanwhile  the velocity was Mach2.5  and the time consists of 10s  20s and 60s. The temperature initial loads were from FLUENT thermal simulation. The thermal conduction analysis and the thermal convection analysis were finished in software ANSYS  in which the entire transient thermal analysis consists of modeling  meshing element  calculating and getting the results. The different temperature distributions based on varied time were gotten about the different materials. The results from analysis showed the temperature distribution of the structure of ellipsoidal dome  which could help the following coupled thermal-structure analysis. 2011 IEEE.  
Design of transmission of high-speed CCD driving signals (EI CONFERENCE) 会议论文
2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011, August 19, 2011 - August 22, 2011, Jilin, China
Zhang S.; Xue X.
收藏  |  浏览/下载：34/0  |  提交时间：2013/03/25
In order to overcome the distortion problem of CCD driving signals caused by signal transmission  the detail implementation of transmission of high-speed CCD driving signals based on transmission line theory is discussed. The CCD driving signals are critical to the CCD to produce high quality images. In high speed application these drivers will occupy more circuit board areas and can not be put very close to the CCD. So the driving signals must be transmitted. Because the CCD exhibits capacitive load  the driving signals distortion problem is much severe. Transmission line theory is used to analyze the problem. The method of source termination is adopted to avoid signal reflections. Meanwhile the characteristic impedance of the circuit board and the resistance of terminal resistor are designed small enough to decrease the rising and falling time of the driving signals. Experimental results show that there is no distortion of the high speed driving signals after transmission. 2011 IEEE.  
Research of error correction of LEO satellite orbit prediction for vehicle-borne tracking and position device (EI CONFERENCE) 会议论文
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
Zhang P.-L.; Guo L.-H.; Wang J.-J.
收藏  |  浏览/下载：20/0  |  提交时间：2013/03/25
Vehicle-borne tracking and position device is used to track LEO satellite. Because of the absence of the target which might be caused by cloud or zenith blind zone  the forecasting data will be used to acquire the target. While orbit prediction has serious errors  the target is always missed. Meanwhile  in its application to the vehicle-borne tracking and position device  due to the base of instability in the tracking process  it will result in significant difference between predicting data and tracking data  so the target will be not tracked rapidly. We applied tracking data to predict satellite orbits by improving Laplace method  and then corrected the error between Predicted data and actual measured data by interpolation method of Lagrange which improves the accuracy of prediction values. The testing data shows the accuracy of predicted data ranging from 3' to 10" for both azimuth and elevation when extrapolated satellite orbit to 7 seconds time. 2010 IEEE.  

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