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Record 13 of
Title:Design and realization of photoelectric theodolite remote control system based on network
Author(s):Peng, Wei(1); Yang, Xiao-Jun(1); Cao, Jian-Zhong(1)
Source: 2011 International Conference on Electric Information and Control Engineering, ICEICE 2011 - Proceedings Volume: Issue: DOI: 10.1109/ICEICE.2011.5778129 Published: 2011
Abstract:A new way to design and realize a net-based photoelectronic theodolite remote control system is proposed. Analyzes the reliability, net delay and net security problems of this system and uses buffer technology to ensure the reliability, uses password authentication technology to solve the security problem, uses multicast technology to improve the efficiency of network transmission, uses data extrapolation to solve the network delay problem. Practical application shows that the system meets the design requirements and makes the equipment unattended. ? 2011 IEEE.
Accession Number: 20112714121448
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Record 14 of
Title:An adaptive VQ method used on interferential multi-spectral image lossless compression
Author(s):Wen, Jia(1,2); Ma, Caiwen(1); Shui, Penglang(1)
Source: Optics Communications Volume: 284 Issue: 1 DOI: 10.1016/j.optcom.2010.08.030 Published: January 1, 2011
Abstract:In this paper, a high efficient adaptive LBG VQ (vector quantization) method is proposed, which is an improved version of the expansion LBG VQ method [1] (proposed in 2009)and exploits the shortest distance from a point to line segment. Moreover, the proposed method is used on the lossless compression of LASIS (Large Aperture Static Imaging Spectrometer) interferential multi-spectral images. Compared with the expansion LBG VQ method proposed in 2009, the experimental results showed that the adaptive LBG VQ method improved the compression performance obviously. And the experiment also showed that when using these LBG VQ methods above without Dual-Direction Prediction [2], the entropy generated by expansion LBG VQ method [1] sometimes will be larger than that generated by traditional LBG VQ method [3], and when using these LBG VQ methods above after Dual-Direction Prediction [2], CR (compression ratio) generated by expansion LBG VQ method [1] sometimes will be less than that generated by traditional LBG VQ method [3], while the entropy generated by the method proposed in this paper will be much less than that generated by either traditional LBG VQ method [3] or the expansion LBG VQ method [1], and CR generated by the method proposed in this paper will be much larger than that generated by either traditional LBG VQ method [3] or the expansion LBG VQ method [1]. ? 2010 Elsevier B.V. All rights reserved.
Accession Number: 20104913460311
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Record 15 of
Title:A fine resampling algorithm for general particle filters
Author(s):Cao, Bei(1,2); Ma, CaiWen(1); Liu, ZhenTao(3)
Source: Proceedings - 4th International Congress on Image and Signal Processing, CISP 2011 Volume: 5 Issue: DOI: 10.1109/CISP.2011.6100779 Published: 2011
Abstract:Resampling algorithm for particle filters aimed at solving particle degeneracy problem but causing sample impoverishment. To maintain the diversity of the particle system and thus enhance the accuracy of state estimation in the nonlinear/non-Gaussian models, the paper proposed an improved resampling algorithm for general particle filters, called as PF-FR (Particle Filters with Fine Resampling). By introducing distance-comparing process and generating new particle based on optimized combination scheme, PF-FR algorithm overcomes the defects of general resampling algorithm. Simulations prove that the proposed PF-FR algorithm can effectively avoid sample impoverishment and simultaneously solve the degeneracy problem, thereby improving the estimation accuracy evidently. As a consequence, PF-FR algorithm is an effective alternative to resampling algorithm. ? 2011 IEEE.
Accession Number: 20120214678732
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Record 16 of
Title:Fuzzy logic controller design based on genetic algorithm for DC motor
Author(s):Liu, Chun-Juan(1); Li, Bian-Xia(1); Yang, Xiao-Xu(1)
Source: 2011 International Conference on Electronics, Communications and Control, ICECC 2011 - Proceedings Volume: Issue: DOI: 10.1109/ICECC.2011.6067555 Published: 2011
Abstract:This paper propose a genetic based fuzzy logic controller to regulate the speed of separately excited DC motor. The fuzzy membership function and rules are optimized based on genetic algorithm. The DC motor speed control system is modeled and simulated in MATLAB/SIMULINK. Simulation results show that the optimized fuzzy logic controller not only has no overshoot, minimum settling times and vibrations, but also demonstrate high performance for real-time control over a wide range of operating conditions. ? 2011 IEEE.
Accession Number: 20114714545068
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Record 17 of
Title:Detection and correction of linear phase error for Fourier transform spectrometer using phase correction method
Author(s):Wang, Cailing(1); Li, Yushan(2); Liu, Xuebin(1); Hu, Bingliang(1); Liu, Caifang(1)
Source: Advanced Materials Research Volume: 225-226 Issue: DOI: 10.4028/www.scientific.net/AMR.225-226.293 Published: 2011
Abstract:Idealy, an interferogram is an even function of the path differences; it suffices to computer the cosine Fourier transform of the interferogram from the zero optical path to the max to produce the spectrum. However, the interferogram is always asymmetry of the scanning function in reality. A method for the phase correction of interferograms in Fourier transform is presented. It is shown that phase error can be canceled to within an arbitrary angular precision by phase correction method. Three original spectrums are provided in which phase correction over a frequency range of 400nm to 1000nm ,they are shown that using Phase Correction Method resulted in a error is less than those of the Mertz Method, and the purchased time is much less than the Mertz Method. The method can be used in most experiments, including emission spectroscopy, where conventional techniques are inadequate. ? (2011) Trans Tech Publications.
Accession Number: 20112013986278
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Record 18 of
Title:Compound tracking in ATP system for free space optical communication
Author(s):Zhang, Min(1); Liang, Yanbing(1)
Source: Proceedings 2011 International Conference on Mechatronic Science, Electric Engineering and Computer, MEC 2011 Volume: Issue: DOI: 10.1109/MEC.2011.6025499 Published: 2011
Abstract:Free space optical (FSO) communication is also called as wireless optical communication. It does not require any wired channel as transmission medium. FSO is a kind of communication technology which transmits information through vacuum or atmosphere. In order to realize point-to-point communication, space optical communication needs to establish a reliable communication link. The traditional coarse tracking technology has been very mature, but low tracking precision is still the main defect, in order to realize high accuracy tracking (arc-second), compound tracking technology is generally adopted. This paper presents the key technology of free space optical communication ATP. The main research is about compound tracking technology, including the design of coarse tracking and fine tracking control system. ? 2011 IEEE.
Accession Number: 20114114423303
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Record 19 of
Title:An acoustic imaging simulation based on microphone array
Author(s):Zhang, Jing(1); Liu, Bo(1); Ding, Lu(1); Chen, Errui(1)
Source: Proceedings of 2011 Cross Strait Quad-Regional Radio Science and Wireless Technology Conference, CSQRWC 2011 Volume: 2 Issue: DOI: 10.1109/CSQRWC.2011.6037226 Published: 2011
Abstract:Based on a brief introduction of microphone array, the overall structure of acoustic imaging system is illustrated in this paper, followed by the description and analysis of the components of this system. After a uniform linear microphone array based on Multiple Signal Classification (MUSIC) algorithm is described and analyzed, the simulation program on the algorithm is developed with MATLAB. The simulation result of the algorithm indicates that: under the condition of same sample numbers, the higher the SNR, the better the image; the similar conclusion can be got under the condition of the same SNR while the sample rate is varied. Such a result is just what we expected. ? 2011 IEEE.
Accession Number: 20114414464496
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Record 20 of
Title:Design and implementation of cooling system for focal plane assembly of observation camera in astronomical satellite
Author(s):Cheng, Pan(1,2); Qu, Youshan(1); Li, Huijuan(1,2); Tan, Jiahai(1)
Source: 2011 International Conference on Electronics, Communications and Control, ICECC 2011 - Proceedings Volume: Issue: DOI: 10.1109/ICECC.2011.6066330 Published: 2011
Abstract:In order to observe dim astronomical objects, the imaging sensor of the Astronomical Observation Camera (AOC) in the satellite needs to work at 65C to suppress its dark current noise. To achieve the low temperature environment, a cooling system on Thermoelectric Cooler (TEC) was designed. The cooling system adopted a Single Chip Microprocessor as its control computing platform and its software used self-adaptive digital PID control algorithm was developed. The data of the real-time temperatures, captured by the acquiring circuits from the temperature sensors which were mounted at the back surface of the imaging sensor, were used to be the input of the self-adaptive digital PID control algorithm, and the output calculated by the algorithm was applied to adjusted the control current of the driver circuit for the TEC, and then the temperature of Focal Plane Assembly (FPA) was cooled down or warmed up to satisfy the working requirements. Experimental results show that the designed system can control the temperature gradient of the FPA less than 1C and reach its normal working temperature 65C quickly. Its control accuracy is 2C. The practical experiment results displayed the imaging performance of the FPA was stable and the designed cooling system suppressed the dark current noise effectively to get high Signal-to-Noise Ratio images, and the designed cooling system worked stable. ? 2011 IEEE.
Accession Number: 20114714544614
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Record 21 of
Title:The novel stable control scheme of the light source power in the closed-loop fiber optic gyroscope
Author(s):Ji, Zhongxiao(1,2); Ma, Caiwen(2)
Source: Journal of Physics: Conference Series Volume: 276 Issue: 1 DOI: 10.1088/1742-6596/276/1/012127 Published: 2011
Abstract:The light source power stability of the Fiber-Optic Gyroscope (FOG) affects directly the scale factor and bias stability of FOG. The typical control scheme of the light source power employs an additional photodetector to detect the output power of the light source. When the fiber loss of FOG varied due to the temperature change, the light power in the additional photodetector did not indicate this change, which decreased the control effect. The spike pulse overlapping on the gyro signal denotes potentially the change of the light power and fiber loss. In the novel scheme, the spike pulse is extracted from the gyro signal, and is transformed into the square wave by the differential circuit. According to the change of the square wave amplitude, FOG adjusts the bias current of the light source to keep the stable light power in the signal photodetector. It is a simple and low-cost scheme without an additional photodetector.
Accession Number: 20111513911254
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Record 22 of
Title:Synthesis of ZnO nanocrystals with different morphologies by hydrothermal method
Author(s):Hang, Lianmao(1); Zhang, Zhiyong(2); Yan, Junfeng(2)
Source: Proceedings of 2011 International Conference on Electronic and Mechanical Engineering and Information Technology, EMEIT 2011 Volume: 6 Issue: DOI: 10.1109/EMEIT.2011.6023685 Published: 2011
Abstract:ZnO nanocrystals with different morphologies have been synthesized by hydrothermal method employing zinc acetate dihydrate [Zn(CH3COO) 22H2O] and sodium hydroxide (NaOH) as the starting reactants and characterized by means of X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM). The results show that the as-synthesized products are hexagonal wurtzite structure of ZnO and exhibit flake-like, flower-like and rod-like structure, respectively. Their growth mechanisms are also tentatively elucidated. ? 2011 IEEE.
Accession Number: 20114014403729
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Record 23 of
Title:Synthesis and photoluminescence of Cr-doped rod-like ZnO particles by hydrothermal method
Author(s):Hang, Lianmao(1); Zhang, Zhiyong(2); Yan, Junfeng(2)
Source: Advanced Materials Research Volume: 306-307 Issue: DOI: 10.4028/www.scientific.net/AMR.306-307.176 Published: 2011
Abstract:Cr-doped rod-like ZnO particles with nominal 3 at% doping concentration were synthesized by hydrothermal method. The structural and optical properties of the sample were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and photoluminescence (PL). The results show that the as-synthesized product is of hexagonal wurtzite structure without metallic Cr or other secondary phases and the morphology of the ZnO particles is rod shaped. The room-temperature PL spectrum of the Cr-doped rod-like ZnO particles exhibits a strong blue emission at 440nm and two weak emission bands centered at 410nm and 565nm, respectively. ? (2011) Trans Tech Publications, Switzerland. ? (2011) Trans Tech Publications, Switzerland.
Accession Number: 20113914367993
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Record 24 of
Title:Application of carbon-carbon composite for load-carrying cylinder in lunar optical telescope
Author(s):Li, Fu(1); Ruan, Ping(1); Li, Ting(1); Xu, Guang-Zhou(1); Lu, Di(1); Pan, Hai-Jun(1,2)
Source: Proceedings of SPIE - The International Society for Optical Engineering Volume: 8196 Issue: DOI: 10.1117/12.900738 Published: 2011
Abstract:The carbon-carbon composite (CCC) was applied in order to design and fabricate much more predominant lunar optical telescope (LOT). The fabricating technics of CCC and machining technics of load-carrying cylinder assembly are introduced. The density of CCC is 1.73g/cm3, and the coefficient of thermal expansion is 0.5×10-6/°C. The thermal adaptability of LOT was analyzed, the operating temperature of LOT will be improved to -20°C～+40°C that the carbon-carbon cylinder is used. Finite element analysis of LOT with CCC cylinder was performed, and the results show that the first frequency of LOT is 185Hz. The machining and assembling of LOT have been performed. The vibration testing has been accomplished and the testing results are consistent with finite element analysis. The testing results show that load-carrying cylinder of CCC can stand the mechanical proof. All analysis and testing indicate that CCC can be competent for LOT. ? 2011 SPIE.
Accession Number: 20113614296280
