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Centroid localization algorithm based on bicubic interpolation gray square weighted (EI CONFERENCE) 会议论文
2012 3rd International Conference on Advances in Materials and Manufacturing Processes, ICAMMP 2012, December 22, 2012 - December 23, 2012, Beihai, China
Zhou J.; Chen X.-L.; Li S.-J.; Huang D.-Y.; Ma G.-Z.
收藏  |  浏览/下载:142/0  |  提交时间:2013/03/25
The 3D coordinates of measured point is embodied in 2D image coordinate of the optical characteristic point via the visual measurement system. Based on the gray square weighted centroid localization algorithm  the paper presents bicubic interpolation gray square weighted centroid localization algorithm  increases the number of effective pixels around the optical characteristic point imaging center  and reduces noise error via the gray square weighted  improves the imaging center location accuracy of optical characteristic point  realizes the accurate location of the optical characteristic points. Results indicate application of the proposed algorithm to location  the standard tolerance along the direction of x is 0.0022 Pixel  the standard tolerance along the direction of y is 0.0023 Pixel  compared with the others  the standard tolerance is minimum and discrete to a lesser degree distancing ideal image point  that is  the proposed algorithm has higher location accuracy. The maximum tolerance along the direction of x is 0.008 Pixel  the one along the direction of y is 0.007 Pixel  compared with the other two algorithms  the maximum tolerance is minimum.Results indicate that the stability of the proposed algorithm is better. (2013) Trans Tech Publications  Switzerland.  
The approximate calculation of atmospheric path radiance in close range and horizontal direction (EI CONFERENCE) 会议论文
2012 International Conference on Sensors, Measurement and Intelligent Materials, ICSMIM 2012, December 26, 2012 - December 27, 2012, Guilin, China
Chang S.; Zhao N.; Sun Z.; Zhang Y.; Chen Y.
收藏  |  浏览/下载:24/0  |  提交时间:2013/03/25
Atmospheric path radiance is the key factor in the accuracy of objective radiation measurement. In the traditional radiation character measurements  it is compared with the results of MODTRAN and measurement in experiment. It is revealed that the accuracy of software is 7.8%  under the help of the atmospheric observation equipment  and the formula is 4.9%  MODTRAN and other software likewise  which could demonstrate the validity of the pproximate calculation formula in close range and horizontal direction. In this article  the indeterminacy rate could be around 10~20%  in the process of deducing and experiment  it is highly restricts the measurement accuracy of objective radiation. For this reason  the validity of the approximate calculation formula in close range and horizontal direction is fully proved  it is quite significant to develop the study of measure and calculation in path radiance. The approximate calculation formula for path radiance in close range and horizontal direction is expressed in this article  which supply a new method in approximate calculation of path radiance for objective radiation measurement. (2013) Trans Tech Publications  Switzerland.  
Data normalization of single camera visual measurement network system (EI CONFERENCE) 会议论文
2012 International Conference on Information Technology and Management Innovation, ICITMI 2012, November 10, 2012 - November 11, 2012, Guangzhou, China
Zhou J.; Li S.-J.; Huang D.-Y.; Chen X.-L.; Zhang Y.-C.
收藏  |  浏览/下载:17/0  |  提交时间:2013/03/25
With the development of visual measurement system  Normalize the measured coordinates into the same world coordinate system  Apply in the three coordinate measuring machine(CMM) to have the simulation experiment  So the data normalization has the advantage of more high precision. (2013) Trans Tech Publications  the visual measurement system of single camera which applied in the imaging theory of optical feature points  then get the global data  the result indicates that the maximum absolute tolerance between the normalization coordinates via the center of point set and the ones measured by CMM directly is 0.058mm  Switzerland.  it has been widespread used in the modern production. Due to the limit of the environment in scene  and achieve the overall measurement  the visual measurement system of single camera could not measure the shield between the measured objects each other. Focus on this problem  But the one between the coordinate repeatedly measured at the position of one network control point is 0.066mm  present a kind of the the knowledge of measurement network based on the visual measurement of single camera  set up the measurement network system via the multi-control points. Measure the optical feature points in every network control point via the visual measurement system of single camera  
Laser cleaning of neutral attenuator plate based on low power laser diode (EI CONFERENCE) 会议论文
2nd International Conference on Energy, Environment and Sustainable Development, EESD 2012, October 12, 2012 - October 14, 2012, Jilin, China
Gan X.; Chen Y.; Li L.
收藏  |  浏览/下载:19/0  |  提交时间:2013/03/25
Laser cleaning is a non-contact  green and environmental cleaning method  which can effectively remove particulate contaminations of sizes as small as 0.1 m without damage to the optics. But most laser cleaning devices are large and heavy  also expensive due to using large lasers such as CO2 laser  YAG Laser etc. In this work a low power LD was tried to clean fingerprint and dust contaminated on the surface of the attenuator glasses plates. In the laser cleaning experiment with low power diode the fingerprint grease can be efficient to be cleaned  but there is no evident effect for cleaning inorganic dust. The cleaning different degree of fingerprint contaminations was investigated at the variable laser parameters  including laser power and irradiation time. An optical microscope was used to analyze the cleaning effect. The results show that low power LD can effectively remove the fingerprint on the surface of absorptive-type attenuator glass plates. On the premise that the attenuator optics glasses are not damaged  the cleaning area increases with the increase of radiation time and laser power. The cleaning area doesn't change much with the variation of laser frequency when the other parameters are the same. (2013) Trans Tech Publications  Switzerland.  
Retrieval of snow depth in Northeast China using FY-3B/MWRI passive microwave remote sensing data (EI CONFERENCE) 会议论文
Satellite Data Compression, Communications, and Processing VIII, August 12, 2012 - August 13, 2012, San Diego, CA, United states
Ren R.; Gu L.; Chen H.; Cao J.
收藏  |  浏览/下载:129/0  |  提交时间:2013/03/25
Comparing with optical remote sensing techniques  passive remote sensing data have been proved to be effective for observing snowpack parameters such as snow depth and snow water equivalent  which can penetrate snowpack without clouds interferences. The Microwave Radiation Imager (MWRI) loaded on the Chinese FengYun-3B (FY-3B) satellite is gradually used in the global environment research through November  2011. In this paper  we proposed a snow depth retrieval algorithm to estimate snow depth in Northeast China using MWRI passive microwave remote sensing data. A decision tree method of snow identification was firstly designed to distinguish different snow cover conditions in order to eliminate other interference signals. After using the proposed decision tree method  the processing results were further used to retrieve the snow depth in Northeast China. Finally  the practical snow depth data and the MODIS data were collected for the accuracy assessment of the proposed snow depth retrieval method. The experimental results demonstrated that the RMSE of snow depth used the proposed method was approximately 3 cm in Northeast China. 2012 SPIE.  
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:21/0  |  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.  
Color filtering method for CFA images based on gradient (EI CONFERENCE) 会议论文
International Conference on Communication Systems and Network Technologies, CSNT 2012, May 11, 2012 - May 13, 2012, Rajkot, Gujrat, India
Sun H.; Wang Y.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
Single-sensor digital cameras capture image by covering the sensor surface with a color filter array(CFA) such that each sensor pixel only samples one of three primary color values  three color is R(red)  G(green) and B(blue). To render a full-color image  need an interpolation process commonly referred to as CFA demosaicking  is required to estimate the other two contributions for producing a full-color image. But  the noise in imaging sensors not only corrupts the color filter array  at the same time introduces artifacts during the color interpolation step and influence quality of images. In order to acquire high quality full-color images  adopt a sort of viable and effective interpolation algorithm based on gradient  at the time of removing the noise  reserve image border and detail information clearly. 2012 IEEE.  
Parameters estimation of BLDC motor for energy storage system (EI CONFERENCE) 会议论文
10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China
Wu J.
收藏  |  浏览/下载:15/0  |  提交时间:2013/03/25
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:46/0  |  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.  
Study on ultra-light secondary baffle for coaxial two-mirror telescope (EI CONFERENCE) 会议论文
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
Zhang L.; Jia X.; Xie P.; Xing L.
收藏  |  浏览/下载:44/0  |  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.  


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