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第五届国际自动控制联合会分数阶导数及其应用会议

作者： Dongling Wang Aiguo Xiao Hunan Key Laboratory for Computation and Simulation in Scienceand Engineering Key Laboratory of Intelligent Computing &Information Processing of Ministry of Education University XiangtanHunan P.R.China Hunan Key Laboratory for Computation and Simulation in Science and Engineering Key Laboratory of Intelligent Computing & Information Processing of Ministry of Education University Xiangtan Hunan P.R.China

In this paper,the fractional variational integrators for fractional variational problems depending on indefinite integrals in terms of Caputo derivative are *** corresponding fractional discrete Euler-Lagrange equatio... 详细信息

关键词： Numerical Methods For Fractional Variational Problems Depending On Indefinite Integrals

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Overlapping area computation between irregular polygons for its evolutionary layout based on convex decomposition

Journal of Software

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Journal of Software 2012年第2期7卷 485-492页

作者： Li, Zi-Qiang He, Yan Tian, Zhuo-Jun School of Information and Engineering of Xiangtan Xiangtan University Hunan 411105 China Key Laboratory of Intelligent Computing and Information Processing of Ministry of Education Xiangtan 411105 China

Low efficiency of interference calculation has become the bottleneck that restricts further development of the performance of evolutionary algorithm for the polygon layout. To solve the problem, in this paper, we propose an algorithm of calculating overlapping area between two irregular polygons. For this algorithm, at first, two irregular polygons are respectively decomposed into the minimum number of convex polygons;afterwards, each pair of the overlapping convex polygons from two resulting partitions is clipped and their overlapping area is calculated. Because through a fast non-overlapping test to all pairs of convex polygons to be clipped, invalid computation is decreased;by making use of simple internal vertex judgment and sheartransformation based on intersecting test and intersection calculation between a line segment and any convex broken line segment, its speed of clipping overlapping convex polygons is improved. The time complexity analysis and numerical experiments indicate that the performance of our presented algorithm superiors to the existing algorithms. © 2012 ACADEMY PUBLISHER.

关键词： Evolutionary algorithms

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Weakening interaction suppresses spontaneous symmetry breaking in two-channel asymmetric exclusion processes

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Physical Review E 2012年第4期85卷 041132-041132页

作者： Kai-Xuan Zhu Nian Wang Qing-Yi Hao Qi-Yi Liu Rui Jiang Key Laboratory of Intelligent Computing and Signal Processing of Education Ministry Anhui University Hefei 230039 China School of Engineering Science University of Science and Technology of China Hefei 230026 China School of Mathematics and Computational Science Anqing Teachers College Anqing 246133 China

This paper has studied spontaneous symmetry breaking (SSB) phenomenon in two types of two-channel asymmetric simple exclusion processes (ASEPs). One common feature of the two systems is that interactions for each species of particle happen at only one site, and the system reduces to two independent ASEPs when interaction vanishes. It is shown that with the weakening of interaction, the SSB is suppressed. More interestingly, the SSB disappears before the interaction is eliminated. Our work thus indicates that local interaction has to be strong enough to produce SSB. The mean-field analysis has been carried out, and the results are consistent with the simulation ones.

关键词： BROKEN symmetry (Physics) MEAN field theory STOCHASTIC processes SIMULATION methods & models STATISTICAL mechanics SYSTEMS theory

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Point Pattern Matching Based on Spectra of Directed Graphs

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电子学报(英文版) 2011年第4期20卷 662-666页

作者： LIANG Dong ZHU Ming FAN Yizheng YAN Pu Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei China

We present a novel algorithm for point pattern matching by means of spectra of directed graphs. Given a feature point-set, we construct a weighted directed graph and skew-symmetric matrix associated with the graph. By using spectral decomposition of the matrix, we give a spectral representation of the feature points with half of the eigenvectors. We theoretically analyze that our method can well deal with the matching problem under affine transformation. The expreiments applied to synthetic data and real-world images show the effectiveness of our method.

关键词：点模式匹配图的谱反对称矩阵特征向量匹配问题仿射变换显示方法谱分解

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P-type Iterative Learning Control of Fractional Order Nonlinear Time-delay Systems

P-type Iterative Learning Control of Fractional Order Nonlin...

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The 24th Chinese Control and Decision Conference (第24届中国控制与决策学术年会 2012 CCDC)

作者： Yong-Hong Lan Lv-Jun He Key Laboratory of Intelligent Computing andInformation Processing of Ministry of Education Xiangtan School of Information Engineering Xiangtan University Xiangtan Hunan 411105 China

This paper presents a P-type iterative learning control (ILC) scheme for a class of fractional-order nonlinear time-delay systems with fractional order α (0 ≤ α < 1). By introducing the λ-norm and using a generalized Gronwall inequality, the *** conditions for the convergence of the control input and the tracking errors for open-loop and closedloop P-type ILC are obtained, respectively. The validity of the methods are *** by a numerical example.

关键词： Fractional order Iterative learning control Generalized Gronwall inequality Convergent

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Numerical dispersion analysis of symplectic and ADI schemes

Numerical dispersion analysis of symplectic and ADI schemes

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International Conference on Microwave and Millimeter Wave Technology Proceedings

作者： Xin-gang Ren Zhi-xiang Huang Xian-liang Wu Si-long Lu Yi-cai Mei Hong-mei Du Hui Wang Jing Shen Key Lab of Intelligent Computing & Signal Processing Ministry of Education Anhui University Hefei China Department of Physics and Electronic Engineering Hefei Normal University Hefei China

In this paper, Maxwell's equations are taken as a Hamiltonian system and then written as Hamiltonian canonical equations by using the functional variation method. The symplectic and ADI schemes, which can be extracted by applying two types of approximation to the time evolution operator, are explicit and implicit scheme in computational electromagnetic simulation, respectively. Since Finite-difference time-domain (FDTD) encounter low accuracy and high dispersion, the more accurate simulation methods can be derived by evaluating the curl operator in the spatial direction with kinds of high order approaches including high order staggered difference, compact finite difference and scaling function approximations. The numerical dispersion of the symplectic and ADI schemes combining with the three high order spatial difference approximations have been analyzed. It has been shown that symplectic scheme combining with compact finite difference and ADI scheme combining with scaling function performance better than other methods. Both schemes can be usefully employed for simulating and solving the large scale electromagnetic problems.

关键词： Dispersion Finite difference methods Function approximation Time domain analysis Maxwell equations Mathematical model

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Perfect plane-wave source for a high-order symplectic finite-difference time-domain scheme

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Chinese Physics B 2011年第11期20卷 365-370页

作者：王辉黄志祥吴先良任信钢 Key Laboratory of Intelligent Computing & Signal Processing of Ministry of Education Anhui University Department of Physics and Electronic Engineering Hefei Normal University

The method of splitting a plane-wave finite-difference time-domain （SP-FDTD） algorithm is presented for the initiation of plane-wave source in the total-field / scattered-field （TF/SF） formulation of high-order symplectic finite- difference time-domain （SFDTD） scheme for the first time. By splitting the fields on one-dimensional grid and using the nature of numerical plane-wave in finite-difference time-domain （FDTD）, the identical dispersion relation can be obtained and proved between the one-dimensional and three-dimensional grids. An efficient plane-wave source is simulated on one-dimensional grid and a perfect match can be achieved for a plane-wave propagating at any angle forming an integer grid cell ratio. Numerical simulations show that the method is valid for SFDTD and the residual field in SF region is shrinked down to -300 dB.

关键词： splitting plane-wave finite-difference time-domain high-order symplectic finite-differencetime-domain scheme plane-wave source

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Generalized two-dimensional FLD with assembled matrix distance metric for face recognition

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Journal of Information and Computational Science 2012年第12期9卷 3439-3446页

作者： Shi, Yuexiang Gong, Ping Tao, Zhiping Key Laboratory of Intelligent Computing and Information Processing of Ministry of Education School of Information Engineering Xiangtan University Xiangtan 411105 China School of Information Engineering Xiangtan University Xiangtan 411105 China

Two-dimensional fisher linear discriminant analysis (2DFLD or 2DLDA) has attracted much attention from researchers recently for the advantages over the singularity problem and the computational cost. Recent research on 2DLDA-based methods has mainly concentrated on two issues, namely: 1) feature extraction and 2) classification. In this paper, we further analyze these two problems simultaneously by using G-2DFLD supplemented with an Assembled Matrix Distance (AMD) metric. For feature extraction, G-2DFLD is proposed, which can be used for image feature extraction by reducing the dimensionality in both horizontal and vertical directions. For classification, an AMD metric is presented to calculate the distance between two feature matrices, then, the nearest neighbor classifier is used for face recognition. To test this new method, ORL face database is used and the results show the efficiency of G-2DFLD with AMD metric in face recognition. © 2012 Binary Information Press.

关键词： Feature extraction

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A novel segmentation method for convex lesions based on dynamic programming with local intra-class variance 12

A novel segmentation method for convex lesions based on dyna...

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27th Annual ACM Symposium on Applied computing, SAC 2012

作者： Yu, Mali Huang, Qiliang Jin, Renchao Song, Enmin Liu, Hong Hung, Chih-Cheng School of Computer Science Huazhong University of Science and Technology Wuhan China Key Laboratory of Education Ministry for Image Processing and Intelligent Control Wuhan Hubei China Radiology Department Second People's Hospital of Nanning Nanning China School of Computing and Software Engineering Southern Polytechnic State University GA United States

ISBN: (纸本)9781450308571

Lesion segmentation plays an important role in medical image processing and analysis. There exist several successful dynamic programming (DP) based segmentation methods for general images. In those methods, the gradient is used as an important factor in the cost function to attract the contours to the boundaries. Since medical images have their characteristics such as low contrast, blurred edges and high noises, the gradient operator cannot work well enough to achieve a satisfactory performance for boundary detection. We define the local intra-class variance and combine it with the dynamic programming method to replace the traditional gradient operation. Experiments on synthetic and X-ray images are carried out and the results are compared with Canny and fast multilevel fuzzy edge detection (FMFED) algorithms. It is demonstrated that the proposed method performs better on medical images with low contrast, blurred edges and high noises. In addition, 483 regions of interest of mammograms randomly extracted from DDSM of the University of South Florida are used to compare our proposed method with the plane-fitting and dynamic programming method (PFDP), and the normalized cut segmentation method (Ncut). The results demonstrate that our method is more accurate and robust than PFDP and Ncut. © 2012 ACM.

关键词： Dynamic programming

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Fast Calculation of RCS over a Broad Frequency Band Using FDM and AWE technique

Fast Calculation of RCS over a Broad Frequency Band Using FD...

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International Symposium on Antennas Propagation and EM Theory

作者： Tao Sheng Yufa Sun Lingyang Kong Key Lab. of Intelligent Computing & Signal Processing Ministry of Education Anhui University

ISBN: (纸本)9781467317993

The fast dipole method (FDM) in conjunction with the asymptotic waveform evaluation (AWE) technique is presented for fast calculation of radar cross section (RCS) from arbitrarily shaped perfect electric conductor targets over a broad frequency band. The FDM, which is based on the equivalent dipole-moment (EDM) method, is employed to reduce impedance matrix storage and accelerate the matrix-vector multiplications in the solutions of the Taylor coefficients. The application of AWE technique enables fast frequency sweep analysis. The numerical results show that this method greatly increased the computational efficiency without losing accuracy conditions compared with the traditional method of moments (MoM) combined with AWE technique.

关键词： Fast dipole method Equivalent dipole-moment Asymptotic waveform evaluation Radar cross section Method of moments

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