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	Three-sample rotation vector algorithm with angular rate input (EI CONFERENCE) 会议论文 OAI收割 2011 2nd International Conference on Mechanic Automation and Control Engineering, MACE 2011, July 15, 2011 - July 17, 2011, Inner Mongolia, China 作者: Zhang Y. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In order to research the attitude algorithm with angular rate input under the conical motion a optimal threesample rotation vector algorithm based on single-step Newton backward interpolation is proposed. Using the principle of limited rigid body rotation and the characteristic of angular rate input three-sample rotation vector algorithm is derivated. To minimum attitude errors three-sample rotation vector algorithm is optimized. Three angular rate extraction methods of singlestep entire sample recursion multi-step entire sample and singlestep Newton backward interpolation are proposed. Under the condition of conical motion with semi-cone angle 3 and angular frequency 2rad/s simulation is done. The simulation results show that single-step Newton backward interpolation is superior to the other two methods and its maximum error peak is 0.01 error drift rate is 0.036/h. Experiments in three-axis flying turntable with the same parameters are carried out and the results show that error drift rates of three-channels are less than those of traditional quaternion which are 13.53% 12.08% and 23.68% lower respectively. It also verified that the new algorithm can perform a high accuracy under the conical motion. 2011 IEEE.
	Schwarz's lemma for the circle packings with the general combinatorics 期刊论文 OAI收割 SCIENCE CHINA-MATHEMATICS, 2010, 卷号: 53, 期号: 2, 页码: 275-288 作者: Huang XiaoJun; Liu JinSong; Shen Liang \| 收藏 \| 浏览/下载：18/0 \| 提交时间：2018/07/30 circle packing discrete extremal length the maximum principle hyperbolic geometry
	A new method of measuring lead screw with dual-frequency laser interference (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China 作者: Qi X.-D. 收藏 \| 浏览/下载：40/0 \| 提交时间：2013/03/25 A new optical structure of measuring lead screw with dual-frequency laser interferometer is proposed and a formula used quickly correcting Abbe error is deduced in this paper. In the process of testing lead screw Abbe error in the measured data can be real time compensated so that the measurement system which doesn't meet Abbe principle can achieve high measurement accuracy. In addition this method can also eliminate measurement error induced by axial movement of the measured lead screw. The experimental result shows that of the maximum residual error is only 0.48m within 300mm stroke after the maximum Abbe error 1.39m is corrected. This method effectively improves the measurement accuracy of lead screw. 2010 IEEE.
	The design of high-speed optical fiber communication system based on PCI bus (EI CONFERENCE) 会议论文 OAI收割 2010 2nd IEEE International Conference on Advanced Management Science, ICAMS 2010, July 9, 2010 - July 11, 2010, Chengdu, China 作者: Zhang L.-G.; Zhang L.-G.; He X. 收藏 \| 浏览/下载：59/0 \| 提交时间：2013/03/25 In order to increase the transmission distance and reduce noise effectively a communication system with the optical fiber interface is developed in this paper. In the system the PCI bus is adopted as the connection bus between the underlying optical fiber transceiver module circuitry and host computer using the WDM driver. The FPGA is the core logic of the whole system responsible for data transmission and timing logic control. The module structure and the design method of the PCI bus the principle and the design of optical interface module and the bottom-driven development are described in this paper. The experiment results show that the system has basically meet requirement targets. It can achieve the maximum transfer rate of 40MBps when running in the DMA mode. With long transmission distance strong antiinterference and high scalability this system has stable and reliable performance. 2010 IEEE.
	Design and analysis of power system of micro-electromechanical actuator (EI CONFERENCE) 会议论文 OAI收割 2010 2nd International Conference on Industrial Mechatronics and Automation, ICIMA 2010, May 30, 2010 - May 31, 2010, Wuhan, China 作者: Zhang J.; Zhang J.; Zhang J. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to apply the electromechanical actuator to tactical mini-missiles maximum rotational speed of output shafts is greater than 250/s. Test results basically correspond to the requirement of technical indexes. It is proved that this analysis and design method is congruent with the design of micro-electromechanical actuators this paper researches on the key technology such as load-bearing ability the system bandwidth can reach 25.3Hz on the condition of no load and 23.4Hz on the condition of load thus the method is feasible. 2010 IEEE. rapidity and miniaturization of the micro-electromechanical actuator power system based on the ball screw. First according to specific technical indexes the power electromechanical time constant and the size of the motors are screened originally through theoretical analysis. Finally based on the characteristics of ball screw transmission load locus of the micro-electromechanical actuator dynamic system is theoretically analyzed and the optimum speed ratio is determined through parameter optimization. The results of the double closed loop controlled test on the principle prototype show: the system can operate normally with 2.5N.m hinge moment
	Estimation algorithm of mobile OFDM CFOs based on step-size (EI CONFERENCE) 会议论文 OAI收割 2009 International Conference on Information Engineering and Computer Science, ICIECS 2009, December 19, 2009 - December 20, 2009, Wuhan, China Lin L.; Qiao Y.-F.; Su W.-X. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In order to maintain orthogonality among subcarriers for mobile OFDM a CFOs step-size estimation model is established to avoid severe performance degradation caused by ICI and algorithmic stability step-size parameter the error of CFOs estimate and etc are investigated. First after an averaging window algorithm is introduced the mathematic model of step-size estimation algorithm is obtained through step-size parameter and time-varying CFOs. Then based on the results of MATLAB simulation the determination of step-size parameter the advantages of step-size algorithm and precision are discussed. Finally time sequence plots of added CP interleaver and subcarrier modulation with VHDL are presented. Experimental results indicate that the maximum of CFOs errors is 0.00987 in 3 variance interval when mobile velocity is 400 km/h according with verdicted principle that in order for the ICI effects to be negligible the error of CFOs estimation must be accurate within 1-2% of the subcarrier spacing and programs can correctly implement on circuit board. 2009 IEEE.
	An edge extracting method of fuzzy thresholding value (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China Gu R.; Zhu M. 收藏 \| 浏览/下载：18/0 \| 提交时间：2013/03/25 This paper discusses image's object edge extracting of threshold value. First this paper introduces fundamental principle of gray image object edge extracting after discussing the influence of object edge image's gray scale distributing characteristic and choice of threshold value to character extracting and target identification we bring forward a sort of method which using object edge fuzzy taxonomy and maximum fuzzy entropy theory to auto choose threshold value in the case that membership function is given then we have a test of threshold value segmentation to edge gray image in different contrast the result indicates this method has preferable scene adaptive faculty.
	Nonlinear stability of the relaxing schemes for scalar conservation laws 期刊论文 OAI收割 APPLIED NUMERICAL MATHEMATICS, 2001, 卷号: 38, 期号: 3, 页码: 347-359 作者: Tang, HZ \| 收藏 \| 浏览/下载：23/0 \| 提交时间：2018/07/30 the relaxing schemes maximum principle TVD hyperbolic conservation laws