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A Cellular-Assisted Efficient Handover Algorithm for Wireless Sensor Networks

International Journal of Communications, Network and System Sciences 2012年第10期5卷 708-713页

作者： Jun Zhu Hui Gao Yuling Ouyang Key Laboratory of Intelligent Computing & Singnal Processing Ministry of Education Anhui University Hefei China Shanghai Research Center for Wireless Communications Shanghai China

Heterogeneous network convergence and handover have become very hot in recent years. This paper proposed an efficient handover scheme in Multi-PAN Wireless Sensor Networks (WSNs). A number of edge nodes are set at the edge of each Personal Area Networks (PANs). A user equipment (UE), which has WSN and cellular network interface, acts as sensor node or mobile cluster head in WSN area. Thus, edge early warning can be acquired from edge nodes and neighbor channel information can be acquired with BS-assistance. Simulation results show that low transmission interrupted delay and low energy consumption can be achieved compared with conventional scheme in WSN.

关键词： Efficient Handover Edge Early Warning Special Beacon Wireless Sensor Networks

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Rate-embedded differential space-frequency codes based on cyclic delay diversity

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Journal of Computational Information Systems 2012年第1期8卷 151-158页

作者： Zhang, Hongwei Xu, Lei Li, Xiaohui Lu, Lu Key Lab of Intelligent Computing and Signal Processing of Ministry of Education Anhui University Hefei 230039 China Anhui Public Security Department Hefei 230061 China

The conventional differential space-frequency codes (DSFC) based on cyclic delay diversity (CDD) only could achieve the same transmission rate with that of a single transmit antenna system, the spectral efficiency was low. To improve the spectral efficiency in a non-coherent multiple antenna system, the advantage of CDD is considered fully in this paper and then a rate-embedded differential space-frequency coding scheme based on grouped CDD is proposed. In the proposed scheme, all transmit antennas are partitioned into several groups firstly, the conventional cyclic delays are adopted to achieve spatial diversity in each group, those symbols among different groups are transmitted differentially with low rate and high rate message matrices alternately, consequently high rate transmission is obtained. Simulation results verify that, compared with the conventional DSFC based on CDD, the proposed coding scheme can achieve obviously higher transmission rates and better error performances. © 2012 Binary Information Press January 2012.

关键词： Spectrum efficiency

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Optic disc localization by projection with vessel distribution and appearance characteristics

Optic disc localization by projection with vessel distributi...

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International Conference on Pattern Recognition

作者： Dongbo Zhang Yao Yi Xingyu Shang Yinghui Peng Key Laboratory of Intelligent Computing & Information Processing of Ministry of Education The College of Information Engineering Xiangtan University China

ISBN: (纸本)9781467322164

Considering the vessel distribution and optic disc (OD) appearance characteristics comprehensively, a novel OD localization method based on 1-D projection is proposed. The horizontal location is determined by vascular scatter degree, an evaluation index of vessel distribution. And the vertical location is found by brightness and edge gradient around OD. The proposed method was tested on four publicly-available databases and a self-selection database. The OD was successfully located in 357 images out of 380 images (94%). And the proposed method shows good robustness in both normal and diseased images.

关键词： Databases Retina Optical imaging Biomedical optical imaging Optical filters Optical scattering Image segmentation

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An application of circumscribed circle filter in the multi-stencils fast marching method 12

An application of circumscribed circle filter in the multi-s...

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27th Annual ACM Symposium on Applied computing, SAC 2012

作者： Liu, Hong Hung, Chih-Cheng Hu, Huaifei Yu, Mali Song, Enmin 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 430074 China School of Computing and Software Engineering Southern Polytechnic State University Marietta GA 30060 United States

ISBN: (纸本)9781450308571

We develop an effective method for improving the segmentation result based on the Multi-Stencils Fast Marching method (MSFM). In MSFM, the gradient information of the image plays a vital role for calculating edges. It is straightforward to obtain the edge of good quality images;however, MSFM may not have robust edge maps available for images with spurious edges. Thus, a special multi-direction circumscribed circle filter is proposed to calculate the image gradient information which is then used in the MSFM. Using the new gradient information, better image contours can be obtained with MSFM. The size of the radius used in our circle filter is constant even the standard deviation of zero-mean Gaussian noise changes while the parameters of mean filter and Canny filter for gradient computation have to be correctly selected according to different noisy images. Our proposed method shows that it is effective through the experiments of image segmentation. © 2012 ACM.

关键词： Image segmentation

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Numerical Methods For Fractional Variational Problems Depending On Indefinite Integrals

Numerical Methods For Fractional Variational Problems Depend...

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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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