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Medical image segmentation using improved FCM

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Science china(Information Sciences) 2012年第5期55卷 1052-1061页

作者： ZHANG XiaoFeng 1,2,ZHANG CaiMing 1,3,4,TANG WenJing 1,2 & WEI ZhenWen 1 1 school of computer Science and technology,Shandong university,Jinan 250101,china 2 school of Information and Electrical Engineering,Ludong university,Yantai 264025,china 3 school of computer Science and technology,Shandong university of Finance and Economics,Jinan 250014,china 4 Shandong Province Key Lab of Digital Media technology,Jinan 250014,china 1. school of computer Science and technology Shandong University Jinan 250101 China2. School of Information and Electrical Engineering Ludong University Yantai 264025 China3. School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China4. Shandong Province Key Lab of Digital Media Technology Jinan 250014 China

Image segmentation is one of the most important problems in medical image processing,and the existence of partial volume effect and other phenomena makes the problem much more *** C-means,as an effective tool to deal with PVE,however,is faced with great challenges in *** at this,this paper proposes one improved FCM algorithm based on the histogram of the given image,which will be denoted as HisFCM and divided into two *** first phase will retrieve several intervals on which to compute cluster centroids,and the second one will perform image segmentation based on improved FCM *** with FCM and other improved algorithms,HisFCM is of much higher efficiency with satisfying *** on medical images show that HisFCM can achieve good segmentation results in less than 0.1 second,and can satisfy real-time requirements of medical image processing.

关键词： FCM histogram image segmentation medical image processing

A new scheme of digital communication using chaotic signals in MIMO channels

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Science china(Information Sciences) 2012年第10期55卷 2183-2193页

作者： MA HuanFei 1 & KAN HaiBin 2 1 school of Mathematical Sciences,Soochow university,Suzhou 215006,china 2 school of computer Science,Fudan university,Shanghai 200433,china 1. school of Mathematical Sciences Soochow University Suzhou 215006 China 2. school of computer Science Fudan University Shanghai 200433 China

This paper proposes a new digital communication scheme,which uses chaotic signals based on the adaptive synchronization and parameter identification technique of chaotic systems reported *** to the multi signal character,this scheme combines the chaotic signal transmission with the MIMO channel technique in a wireless environment,which is different from the traditional chaotic communication *** a practical perspective,an outline of modulation,channel model,demodulation and non-coherent detection is ***,system performance is evaluated by simulations,and improvements on this scheme are also discussed.

关键词： chaotic modulation chaotic digital communication mapping parameters MIMO channel

An efficient quantum secret sharing protocol with orthogonal product states

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 331-338页

作者： YANG YuGuang1,2, WEN QiaoYan3 & ZHU FuChen4 1 school of computer, Beijing university of technology, Beijing 100022, china 2 State Key Laboratory of Information Security, Graduate university of Chinese Academy of Sciences, Beijing 100022, china 3 school of Science, Beijing university of Posts and Telecommunications, Beijing 100876, china 4 national Key Laboratory for Modern Communications, Chengdu 610041, china 1. school of computer Beijing University of Technology Beijing 100022 China 2. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100022 China 3. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China 4. national Key Laboratory for Modern Communications Chengdu 610041 China

An efficient quantum secret sharing protocol with orthogonal product states in the 33 Hilbert space is presented. The particles in the orthogonal product states form two particle sequences. One sequence is sent to Bob and the other is sent to Charlie after rearranging the particle orders. With the help of Alice, Bob and Charlie make the corresponding local measurement to obtain the information of the or- thogonal product states prepared. This protocol has many distinct features such as great capacity and high efficiency.

关键词： quantum secret sharing orthogonal product state orthogonal measurement

Statistical modeling and analysis of the influence of antenna polarization error on received power

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Progress in Natural Science:Materials International 2002年第4期 67-71页

作者： WANG Xuesong , ZENG Yonghu, CHEN Zhijie , XU Zhenhai and LI Yongzhen( school of Electronic Science and Engineering, national university of defense technology, changsha 410073, china Department of Foundation, national university of defense technology, changsha 410073, china)

The problem of statistical modeling of antenna polarization error is studied and the statistical characteristics of antenna's received power are analyzed. A novel Stokes-vector-based method is presented to describe the conception of antenna's polarization purity. Statistical model of antenna's polarization error in polarization domain is then built up. When an antenna with polarization error of uniform distribution is illuminated by an arbitrary polarized incident field, the probability density of antenna's received power is derived analytically. Finally, a group of curves of deviation and standard deviation of received power are plotted numerically.

关键词： antenna polarization purity received power statistical distribution.

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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Science china(Information Sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2,LI Gang 3 & GENG HuanTong 1 1 school of computer and Software,Nanjing university of Information Science & technology,Nanjing 210044,china 2 Network Information Center,Nanjing university of Information Science & technology, Nanjing 210044,china 3 school of Mathematics and Physics,Nanjing university of Information Science & technology,Nanjing 210044,china 1. school of computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. Network Information Center Nanjing University of Information Science & Technology Nanjing 210044 China3. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

Threshold quantum secure direct communication without entanglement

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Science china(Physics,Mechanics & Astronomy) 2008年第2期51卷 176-183页

作者： YANG YuGuang1,3 & WEN QiaoYan2 1 College of computer Science and technology, Beijing university of technology, Beijing 100022, china 2 school of Science, Beijing university of Posts and Telecommunications, Beijing 100876, china 3 State Key Laboratory of Information Security (Graduate school of Chinese Academy of Sciences), Beijing 100049, china 1. College of computer Science and technology Beijing University of Technology Beijing 100022 China 3. State Key Laboratory of Information Security (Graduate school of Chinese Academy of Sciences) Beijing 100049 China 2. school of Science Beijing University of Posts and Telecommunications Beijing 100876 China

For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology.

关键词： quantum secure direct communication threshold secure direct communication quantum secret sharing

Algorithm of simulation time synchronization over large-scale nodes

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Science in china(Series F) 2008年第9期51卷 1239-1255页

作者： ZHAO QinPing1,2,ZHOU Zhong1,2 & Lü Fang1,2 1 State Key Laboratory of Virtual Reality technology and Systems,Beihang university,Beijing 100083,china 2 school of computer Science and Engineering,Beihang university,Beijing 100083,china State Key Laboratory of Virtual Reality technology and Systems Beihang University Beijing 100083 China school of computer Science and Engineering Beihang University Beijing 100083 China

In distributed simulation, there is no uniform physical clock. And delay cannot be estimated because of jitter. So simulation time synchronization is essential for the event consistency among nodes. This paper investigates time synchronization algorithms over large-scale distributed nodes, analyzes LBTS （lower bound time stamp） computation model described in IEEE HLA standard, and then presents a grouped LBTS model. In fact, there is a default premise for existing algorithms that controi packets must be delivered via reliable transportation. Although, a theorem of time synchronization message＇s reliability is proposed, which proves that only those control messages that constrain time advance need reliability. It breaks out the default premise for reliability. Then multicast is introduced into the transmis- sion of control messages, and algorithm MCTS （multi-node coordination time synchronization） is proposed based on multicast. MCTS not only promotes the time advance efficiency, but also reduces the occupied network bandwidth. Experiment results demonstrate that the algorithm is better than others in both time advance speed and occupied network bandwidth. Its time advance speed is about 50 times per second when there are 1000 nodes, approximately equal to that of similar systems when there are 100 nodes.

关键词： distributed simulation time synchronization multi-node coordination LBTS multicast

Accountability Analysis of Electronic Commerce Protocols by Finite Automaton Model

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Wuhan university Journal of Natural Sciences 2004年第3期9卷 293-295页

作者： Xie Xiao-yao 1,2 , Zhang Huan-guo 1 1. school of computer, Wuhan university, Wuhan 430072, Hubei, china 2. Institute of Network technology, Guizhou university of technology, Guiyang 550003, Guizhou, china Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Guizhou university of technology Institute of Network Technology Guiyang Guizhou China (GRID:grid.443382.a) (ISNI:***) Wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The accountability of electronic commerce protocols is an important aspect to insures security of electronic transaction. This paper proposes to use Finite Automaton (FA) model as a new kind of framework to analyze the transaction protocols in the application of electronic commerce. Key words finite automaton - electronic commerce - nonrepudiation - information security CLC number TP 393. 08 Foundation item: Supported by the national Natural Science Foundation of china (66973034, 90104005, 60373087)Biography: Xie Xiao-yao (1952-), male, Professor, Ph. D candidate, research direction: information security.

关键词： finite automaton electronic commerce nonrepudiation information security

New method for measuring the degree of conflict among general basic probability assignments

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Science china(Information Sciences) 2012年第2期55卷 312-321页

作者： HE You1,HU LiFang1,2,GUAN Xin1,3,DENG Yong4 & HAN DeQiang5 1Research Institute of Information Fusion,Naval Aeronautical and Astronautical university,Yantai 264001,china 2Navy Armament Academy,Beijing 102249,china 3The Institute of Electronic Science and Engineering,national university of defense technology,changsha 410073,china 4school of Electronics and Information technology,Shanghai Jiao Tong university,Shanghai 200240,china 5Institute of Integrated Automation,Xi'an Jiaotong university,Xi'an 710049,china 1. Research Institute of Information Fusion Naval Aeronautical and Astronautical University Yantai 264001 China2. Navy Armament Academy Beijing 102249 China3. The Institute of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China4. School of Electronics and Information Technology Shanghai Jiao Tong University Shanghai 200240 China5. Institute of Integrated Automation Xi’an Jiaotong University Xi’an 710049 China

There is doubt about Dempster's rule of combination because of counter-intuitive results when dealing with conflict information in intelligent ***,many modified combination rules have been presented in the literature on multi-source information fusion and reasoning with ***,the issue of identifying conflict among evidence has been ignored.A new parameter measuring conflict evidence called the conflict distance parameter is defined to determine whether there are conflicts in evidence based on the analysis of existing conflict *** the same time,a decisive rule,which a reasonable conflict measure function should satisfy,is put ***,an analysis of two typical counter-intuitive situations is given,showing that the new parameter can not only satisfy the decisive rule,but can also attain the same effect as a two-dimensional measure when deciding whether to use the Dempster's rule of combination,and can exceed its effect when deciding whether to use Dezert-Smarandache theory.

关键词： conflict evidence Dezert-Smarandache theory Dempster’s rule of combination information fusion uncertainty