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	Improved TOPS about direction of arrival estimation for wideband signals (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Vibration, Structural Engineering and Measurement, ICVSEM2011, October 21, 2011 - October 23, 2011, Shanghai, China 作者: He B. 收藏 \| 浏览/下载：17/0 \| 提交时间：2013/03/25 The study about the direction-of-arrival (DOA) estimation for wideband signals is a basic topic of Signal Processing. The method called test of orthogonality of projected subspaces (TOPS) does not require initial values to form focusing matrix compared with the coherent signal subspace method (CSSM) but it has poor performance for coherent wideband signals at low signal-to-noise ratio (SNR). Based on the lack of the conventional TOPS this paper reconstructs a set of new matrices with the narrowband correlated matrices coming from the DFT decomposition of the array output and modifies the method frame of the conventional TOPS. So we get a set of reconstructed matrices with full rank corresponding to each frequency bin and which have no array aperture loss. The improved TOPS can estimate the DOA for coherent wideband sources at low SNR and enhances the performance of the conventional TOPS. Simulation results show that the improved TOPS is effective and the total performance of which is similar to the rotational signal-subspace (RSS) method. (2012) Trans Tech Publications.
	The research of the accurate measure of static transfer function for the TDI CCD camera (EI CONFERENCE) 会议论文 OAI收割 3rd International Photonics and OptoElectronics Meetings, POEM 2010, November 2, 2010 - November 5, 2010, Wuhan, China Guo-Ning L.; Long-Xu J.; Jian-Yue R.; Wen-Hua W.; Shuang-Li H. 收藏 \| 浏览/下载：25/0 \| 提交时间：2013/03/25 In the test course of static transfer function of TDI CCD camera because of the influence that gets environmental and artificial etc. factor the value of static transfer function measured at any time is between unceasing fluctuation so make accuracy reduce. To solve this problem a kind of accurate measurement technique of static transfer function is put forward. First before carrying out the measure of static quiet of transfer function the best test point of transfer function of the TDI CCD camera must be determined it is parallel to guarantee the rectangle target surface of parallel optical pipe and camera focal plane maintenance parallel and again guarantee target strip in rectangle target and TDI CCD in camera focal plane maintenance vertical. TDI CCD catches rectangle target image per 1000 lines of target mark image as a measures sample of static transfer function exclude because of atmosphere tremble twisted vague rectangle target mark image retain 500 distinct and steady target mark image as measure sample set. Then calculate the static transfer function of each measure sample respectively take the average of all static quiet transfer function in measure sample set as the static transfer function of camera. Finally the measure of the static transfer function for TDI CCD camera makes error analysis. Experimental results indicate that the value of the static transfer function of TDI CCD camera measured with this kind of method is 0.2923 with before measurement technique comparison the value of static transfer function has raised 0.02 makes the accuracy of the measure of static transfer function have gotten raising.
	The flow field analysis of the automotive power streering congtrol unit's flow channel (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China Cheng K.; Yan L.; Li G.; Tang J. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 The automotive power steering units must be taken performance test after they are integrated assembly and then left the factory if it is qualified.Because its internal flow channel is very complicated and the residual hydraulic oil can not be eleminated clearly.So we can set up a 3D model flow channel based on CATIA and use FLUENT software to analysis the key flow channel analysing it's pressure distribution and velocity vector diagram then get the real reasonable resluts which can provide the basic for the ejector designing. (2011) Trans Tech Publications.
	Miniature field bus data recorder (EI CONFERENCE) 会议论文 OAI收割 2010 WASE International Conference on Information Engineering, ICIE 2010, August 14, 2010 - August 15, 2010, Beidaihe, Hebei, China Chen C.-Q.; Ji Y. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 The common bus on bus control is RS232. With the development of field bus technology field bus technology is widely used in data recorder. How to real time record the data of field bus in the experiment and provide the test data for process reconstruction is a very important problem. This paper introduces a kind of data acquisition and storage based on field bus. Its core design is C8051F040 microprocessor and SJA1000 a widely used field bus controller. This paper presents the basic constitution of this field bus data recorder and set forth its hardware and software. This field bus data recorder field bus real-time gathers the information and storage data on the CF card. The result of the experiment shows the system is highly reliable for data acquisition and storage which should have abroad application prospect for data record experiment. 2010 IEEE.
	Miniaturize photoelectric stable platform (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer Application and System Modeling, ICCASM 2010, October 22, 2010 - October 24, 2010, Shanxi, Taiyuan, China Xue W.-Q.; Wang Y.-Y.; Dai M. 收藏 \| 浏览/下载：78/0 \| 提交时间：2013/03/25 In order to reduce the size and weight of the gimbal in a traditional stable platform and correct the disadvantage in size of the payload the paper first improves the gimbal which is an important component of a stable photoelectric platform that also is an important factor in affecting the size and weight of a stability platform. In this paper a closed-form solution of 3-DOF manipulator is designed according mechanical arm design principles. This manipulator is formed by a three joint axes whose extended line is intersected at one point. A standard orthogonal coordinate system is set up for each rod in the manipulator. And then rotation transformation matrix expression is obtained. At last in this paper the manipulator arm-shaped method for solving solutions is description and also each parameter of the gimbal is calculated when the photoelectric detection devices at bottom reach the expected position. Test results show that the photoelectric stability platform with gimbal we designed is smaller lighter and simpler than that traditional. Also the packaging and size of the photoelectric will not be affected with this open structure. 2010 IEEE.
	一种基于安全状态转移的简并测试集生成方法期刊论文 OAI收割软件学报, 2010, 卷号: 21, 期号: 3, 页码: 539-547 程亮; 张阳; 冯登国 \| 收藏 \| 浏览/下载：30/0 \| 提交时间：2011/05/23 安全操作系统测评形式化方法模型检测测试用例化简简并测试集security operating system verification formal method model checking test case optimization degenerate test set
	Alignment of off-axis asphere and compensator with four poles (EI CONFERENCE) 会议论文 OAI收割 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test and Measurement Technology and Equipment, November 19, 2008 - November 21, 2008, Chengdu, China 作者: Li J.; Chen Y.; Li J.; Li J.; Wang P. 收藏 \| 浏览/下载：58/0 \| 提交时间：2013/03/25 Aspheres are utilized widely thanks to the development of optical design manufacture and testing. Compensators are usually necessary when aspheres are under test. The alignment of aspheres and their compensators is a risk because it's tough to check whether the compensators work in right way. A new method of alignment with four poles is put forward in this paper. Optical interval error can be tight while it is quite important due to direct influence on central curvature conic constant and high order coefficients of aspherical surface. A modified on-axis Foucault apparatus is set up since it makes the optical axis visible and helps to control the error of off-axis amount. Some small holes are drilled in the metallic cell of the compensator so that the ends of poles can be stably relied on in order to increase operational repeatability. The method has been carried out practically and it matches the measurement result given by a set of theodolites. 2009 SPIE.
	A new early stopping algorithm for improving neural network generalization (EI CONFERENCE) 会议论文 OAI收割 2009 2nd International Conference on Intelligent Computing Technology and Automation, ICICTA 2009, October 10, 2009 - October 11, 2009, Changsha, Hunan, China 作者: Liu J.-G.; Wu X.-X. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 As generalization ability of neural network was restricted by overfitting problem in the network's training. Early stopping algorithm based on fuzzy clustering was put forward to solve this problem in this paper. Subtractive clustering and Fuzzy C-Means clustering (FCM) were combined to realize optimal division of training set validation set and test set. How to realize this algorithm in backpropagation (BP) network by utilizing neural network toolbox and fuzzy logic toolbox in MATLAB was dwelled on. Early stopping algorithm based on fuzzy clustering and other early stopping algorithms were applied in function approximation and pattern recognition problems in validation experiments. Experiments results indicate that early stopping algorithm based on fuzzy clustering has higher precision in comparison to other early stopping algorithms. Outputs of training set validation set and test set are more accordant. 2009 IEEE.
	Shallow Water Model On Cubed-Sphere By Multi-Moment Finite Volume Method 期刊论文 OAI收割 Journal of Computational Physics, 2008, 页码: 5019-5044 作者: Chen CG(陈春刚); Xiao F(肖锋) 收藏 \| 浏览/下载：865/25 \| 提交时间：2009/08/03 Finite Volume Method Cubed-Sphere Grid Shallow Water Equations Spherical Geometry Global Model High-Order Scheme Geophysical Flows Semi-Lagrangian Advection Barotropic Vorticity Equation Discontinuous Galerkin Incompressible Flows Unified Formulation Conservation-Laws Test Set Integration Scheme Transport