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Multi-polarimetric SAR image compression based on sparse representation

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Science china(information Sciences) 2012年第8期55卷 1888-1897页

作者： CHEN Yuan,ZHANG Rong&YIN Dong department of electronic engineering and information Science,university of Science and Technology of china,hefei 230027,china 1. department of electronic engineering and information Science University of Science and Technology of China Hefei 230027 China

The use of sparse representation in signal and image processing has gradually increased over the past few *** an over-complete dictionary from a set of signals allows us to represent these signals as a sparse linear combination of dictionary *** considering the relativity among the multi-polarimetric synthetic aperture radar(SAR)images,a new compression scheme for multi-polarimetric SAR image based sparse representation is *** multilevel dictionary is learned iteratively in the 9/7 wavelet domain using a single channel SAR image,and the other channels are compressed by sparse approximation,also in the 9/7 wavelet domain,followed by entropy coding of the sparse *** experimental results are compared with two state-of-the-art compression methods:SPIHT(set partitioning in hierarchical trees)and *** of the efficiency of the coding scheme,our method outperforms both SPIHT and JPEG2000 in terms of peak signal-to-noise ratio(PSNR)and edge preservation index(EPI).

关键词： multi-polarimetric SAR image compression sparse representation multilevel dictionary learning edge preservation index(EPI)

A multicast routing algorithm with multiple trees

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Journal of Systems engineering and electronics 2005年第2期16卷 426-432页

作者： Cui Xunxue 1,2 , Gao Wei3 & Fang Hongyu41. New Star Research Institute of Applied Technology, hefei 230031, P. R. china 2. Jiangsu Key Laboratory of Computer information Processing Technology,Soochow university, Suzhou 215006, P. R. china 3. department of electronic engineering and information Science,university of Science and Technology of china, hefei 230027, P. R. china 4. School of electronic Science and Technology, Anhui university, hefei 230039, P. R. china New Star Research Institute of Applied Technology Hefei 230031 P. R. China 2. Jiangsu Key Laboratory of Computer information Processing Technology Soochow University Suzhou 215006 P. R. China department of electronic engineering and information Science University of Science and Technology of China Hefei 230027 P. R. China School of electronic Science and Technology Anhui University Hefei 230039 P. R. China

Quality of service (QoS) multicast routing has continued to be a very important research topic in the Internet. A method of multicast routing is proposed to simultaneously optimize several parameters based on multiobjective genetic algorithm, after the related work is reviewed. The contribution lies on that the selection process of such routing is treated with multiobjective optimization. Different quality criterions in IP network are taken into account for multicast communications. A set of routing trees is generated to approximate the Pareto front of multicast problem. Multiple trees can be selected from the final set of nondominated solutions, and applied to obtain a good overall link cost and balance traffic distribution according to some simulation results.

关键词： multicast routing quality of service multiobjective optimization genetic algorithms.

Notifiable infectious disease surveillance with data collected by search engine

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Journal of Zhejiang university-Science C(Computers and electronics) 2010年第4期11卷 241-248页

作者： Xi-chuan ZHOU1,Hai-bin SHEN2 (1department of information Science and electronic engineering,Zhejiang university,Hangzhou 310027,china) (2School of electrical engineering,Zhejiang university,Hangzhou 310027,china) department of information Science and electronic engineering Zhejiang University Hangzhou China School of electrical engineering Zhejiang University Hangzhou China

Notifiable infectious diseases are a major public health concern in china,causing about five million illnesses and twelve thousand deaths every *** detection of disease activity,when followed by a rapid response,can reduce both social and medical impact of the *** aim to improve early detection by monitoring health-seeking behavior and disease-related news over the ***,we counted unique search queries submitted to the Baidu search engine in 2008 that contained disease-related search *** we counted the news articles aggregated by Baidu's robot programs that contained disease-related *** found that the search frequency data and the news count data both have distinct temporal association with disease *** adopted a linear model and used searches and news with 1–200-day lead time as explanatory variables to predict the number of infections and deaths attributable to four notifiable infectious diseases,i.e.,scarlet fever,dysentery,AIDS,and *** the search frequency data and news count data,our approach can quantitatively estimate up-to-date epidemic trends 10–40 days ahead of the release of Chinese Centers for Disease Control and Prevention(Chinese CDC)*** approach may provide an additional tool for notifiable infectious disease surveillance.

关键词： Notifiable infectious diseases Disease surveillance Search engine

A fast stereoscopic video coding algorithm based on JMVM

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Science china(information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2 , JIA KeBin 1 , CHAN YuiLam 2 , FU ChangHong 2 & SIU WanChi 2 1 department of electronic information & Control engineering, Beijing university of Technology, Beijing 100124, china 2 department of electronic information engineering, Hong Kong Polytechnic university, Hong Kong, china 1. department of electronic information & Control engineering Beijing University of Technology Beijing 100124 China2. Department of Electronic Information Engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.264 stereoscopic video coding disparity estimation motion estimation

New concurrent digital signature scheme based on the computational Diffie-Hellman problem

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The Journal of china Universities of Posts and Telecommunications 2010年第6期17卷 89-94,100页

作者： QIN Wen,ZHOU Nan-run department of electronic information engineering,Nanchang university,Nanchang 330031,china [a] department of electronic information engineering Nanchang University Nanchang 330031 China

Based on strong designated verifiers signatures,a new fair concurrent signature scheme is proposed. Compared with the previous concurrent signature schemes,even if a keystone must be chosen by the initial signer,the matching signer will easily get the keystone through an extraction algorithm. Due to the property of strong designate verifying,the initial signer couldn＇t make use of the keystone prepared carefully to deceive the matching signer. Then the matching signer is able to participate actively the signature scheme. Besides,there aren＇t bilinear operations in the keystone algorithm to deliver the keystone efficiently. Therefore the efficiency of our signature scheme is also improved.

关键词： designated verifiers signature fairness concurrent signature information security

An unsupervised grid-based approach for clustering analysis

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Science china(information Sciences) 2010年第7期53卷 1345-1357页

作者： YUE ShiHong1, WANG JeenShing2, TAO Gao1 & WANG HuaXiang1 1School of electrical engineering and Automation, Tianjin Key Laboratory of Process Measurement and Control, Tianjin university, Tianjin 300072, china 2department of electrical engineering, National Cheng Kung university, Tainan 701, china 1. School of electrical engineering and Automation Tianjin Key Laboratory of Process Measurement and Control Tianjin University Tianjin 300072 China2. Department of Electrical Engineering National Cheng Kung University Tainan 701 China

In recent years, the growing volume of data in numerous clustering tasks has greatly boosted the existing clustering algorithms in dealing with very large datasets. The K-means has been one of the most popular clustering algorithms because of its simplicity and easiness in application, but its effciency and effectiveness for large datasets are often unacceptable. In contrast to the K-means algorithm, most existing grid-clustering algorithms have linear time and space complexities and thus can perform well for large datasets. In this paper, we propose a grid-based partitional algorithm to overcome the drawbacks of the K-means clustering algorithm. This new algorithm is based on two major concepts: 1) maximizing the average density of a group of grids instead of minimizing the minimal square error which is applied in the K-means algorithm, and 2) using grid- clustering algorithms to thoroughly reformulate the object-driven assigning in the K-means algorithm into a new grid-driven assigning. Consequently, our proposed algorithm obtains an average speed-up about 10-100 times faster and produces better partitions than those by the K-means algorithm. Also, compared with the K-means algorithm, our proposed algorithm has ability to partition any dataset when the number of clusters is unknown. The effectiveness of our proposed algorithm has been demonstrated through successfully clustering datasets with different features in comparison with the other three typical clustering algorithms besides the K-means algorithm.

关键词： clustering grid-based algorithm K-means algorithm

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2, TANG Jun 2 , ZHANG AiHua 3 & JIA Ya 2 1 department of Physics, Lanzhou university of Technology, Lanzhou 730050, china 2 department of Physics, Central china Normal university, Wuhan 430079, china 3 College of electrical and information engineering, Lanzhou university of Technology, Lanzhou 730050, china 1. department of Physics Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

Performance of iteratively decoded bit-interleaved coded modulation with chaos based interleaving strategies

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Science china(information Sciences) 2010年第4期53卷 833-841页

作者： ZOU XueLan1*, LIU WeiYan2 & FENG GuangZeng3 1department of electronic and information engineering, Zhejiang Institute of Media and Communications, Hangzhou 310018, china 2department of information engineering, Jiangsu City Vocation College, Nanjing 210036, china 3College of Communication and information engineering, Nanjing university of Posts and Telecommunications, Nanjing 210003, china 1. department of electronic and information engineering Zhejiang Institute of Media and Communications Hangzhou 310018 China2. Department of Information Engineering Jiangsu City Vocation College Nanjing 210036 China3. College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China

Bit-interleaved coded modulation with iterative decoding (BICM-ID) is a bandwidth efficient trans- mission scheme which is well suitable for next-generation mobile communications. The interleaver design is critical to the high performance of BICM-ID. In this paper we investigate the application of the chaos theory to the interleaver design to further improve the performance of BICM-ID. A new interleaving scheme based on the chaos theory is proposed. Compared with the random interleaver, the proposed approach has the ad- vantages including lower system delay and higher transmission efficiency. Simulation results in both additive white Gaussian noise (AWGN) channel and Rayleigh fading channel are provided, which demonstrates that the new interleaver is better than the random interleaver and exhibits excellent performance when applied to the BICM-ID system.

关键词： chaos interleaving bit-interleaved coded modulation (BICM) iterative decoding

Design,analysis and control of hybrid excited doubly salient stator-permanent-magnet motor

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Science china(Technological Sciences) 2010年第1期53卷 188-199页

作者： ZHU XiaoYong1,2 & CHENG Ming1 1 engineering Research Center for Motion Control of MOE,School of electrical engineering,Southeast university,Nanjing 210096,china 2 School of electrical and information engineering,Jiangsu university,Zhenjiang 212013,china 1. engineering Research Center for Motion Control of MOE School of Electrical Engineering Southeast University Nanjing 210096 China2. School of Electrical and Information Engineering Jiangsu University Zhenjiang 212013 China

In this paper,a new hybrid excited doubly salient stator-permanent-magnet motor is proposed,where both permanent magnets and DC field windings are located in the *** theory,the mathematical model and design method of the motor are *** corresponding output power equation and the relationship between the flux control capability and the extended speed range are deduced in *** using an efficient "one-step" three-dimensional(3D) finite element method,the electromagnetic performances are analyzed,in which the leakage flux outside the stator circumference and end-effect are taken into *** on the operation principle of the motor,the control strategy and scheme are developed and implemented *** experimental results and finite element analysis show that the proposed motor not only maintains the advantages of doubly salient permanent magnet motors,but also offers high energy efficiency over a wide speed range,which makes the motor an interesting candidate for electric vehicles.

关键词： stator permanent magnet motor hybrid excitation doubly salient finite element method flux weakening control