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The universal fuzzy logical framework of neural circuits and its application in modeling primary visual cortex

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science china(Life sciences) 2008年第10期51卷 902-912页

作者： HU Hong1, LI Su2, WANG YunJiu2, QI XiangLin2 & SHI ZhongZhi1 1 key laboratory of Intelligent information Processing, Institute of Computing technology, Chinese Academy of sciences, beijing 100080, china 2 laboratory of Visual information Processing, Institute of Biophysics, Chinese Academy of sciences, beijing 100101, china 1. key laboratory of Intelligent information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China 2. laboratory of Visual information Processing Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

Analytical study of large-scale nonlinear neural circuits is a difficult task. Here we analyze the function of neural systems by probing the fuzzy logical framework of the neural cells' dynamical equations. Al- though there is a close relation between the theories of fuzzy logical systems and neural systems and many papers investigate this subject, most investigations focus on finding new functions of neural systems by hybridizing fuzzy logical and neural system. In this paper, the fuzzy logical framework of neural cells is used to understand the nonlinear dynamic attributes of a common neural system by abstracting the fuzzy logical framework of a neural cell. Our analysis enables the educated design of network models for classes of computation. As an example, a recurrent network model of the primary visual cortex has been built and tested using this approach.

关键词： nonlinear dynamical system fuzzy logic visual cortex

Gray physical interference model based link scheduling algorithms

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science china(information sciences) 2012年第6期55卷 1337-1350页

作者： SU JinZhao 1,2,CAO Jing 1,2 & WU Wei 1,2 1 State key laboratory of Virtual Reality and Systems,beijing 100191,china 2 School of Computer science and Engineering,Beihang University,beijing 100191,china 1. State key laboratory of Virtual Reality and Systems Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

To improve the concurrent data transmission capability of wireless multi-hop networks,this paper proposes adopting a gray physical interference model instead of using the threshold physical interference *** model allows non-ideal links to be involved in scheduling,under the premise of not affecting the quality of existing transmission *** addition,we design two greedy algorithms to schedule more links with SINR values located in the transition *** results show that a gray physical interference model is more accurate than a threshold physical interference one,the concurrent transmission capability of a network based on the gray physical interference model is significantly increased,and network throughput is increased by 20%.

关键词： gray physical interference model threshold physical interference model link scheduling concurrent transmission TDMA

Displacement residual based DDM matching algorithm

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science china(information sciences) 2012年第9期55卷 2090-2101页

作者： ZHANG Lin 1,2,ZHOU Zhong 1,2,LIU Lin 1,2 & WU Wei 1,2 1 State key laboratory of Virtual Reality technology and Systems,Beihang University,beijing 100191,china 2 School of Computer science and Engineering,Beihang University,beijing 100191,china 1. State key laboratory of Virtual Reality technology and Systems Beihang University Beijing 100191 China2. School of Computer Science and Engineering Beihang University Beijing 100191 China

High level architecture(HLA) is the prevailing standard for modeling and *** data distribution management(DDM) service of HLA is defined for reducing the delivery of irrelevant *** key in DDM implementation is the region overlap computation,*** matching between update and subscription *** algorithms usually make a compromise between region fidelity and network *** paper takes both the matching algorithm efficiency and bandwidth cost into *** main contributions are:1) illustrating the relationship between region changes and overlap changes,as helps reduce the number of region matching and then improves the total matching efficiency;2) classifying region updates into two types of data expression,snapshot and *** network traffic will be reduced by transmitting only residual data instead of full region representations ***,a region matching algorithm called displacement residual-based DDM matching(DRBM) is proposed in the *** analysis,algorithm implementation and experiment evaluation are *** results show that DRBM provides better matching performance and significant network payload reductions especially when there is a large number of changing regions.

关键词： distributed simulation high level architecture data distribution management region snapshot region residual

Experimental investigation of MIMO relay channels statistics and capacity based on wideband outdoor measurements at 2.35 GHz

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science china(information sciences) 2011年第9期54卷 1945-1956页

作者： NIE Xin 1,2,ZHANG JianHua 1,2,LIU ZeMin 1 & ZHANG Ping 1,2 1 key laboratory of Universal Wireless Communications,Ministry of Education beijing University of Posts and Telecommunications,beijing 100876,china 2 Wireless technology Innovation Institute,beijing University of Posts and Telecommunications,beijing 100876,china 1. key laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China2. Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Relay,which serves to enhance the performance of future communication networks,is one of the most promising techniques for IMT-advanced *** potential performance improvement of relay is investigated in this *** investigation consists of two *** the first step,to obtain a better understanding of the fundamental properties of relay channels,we conducted outdoor measurements at 2.35 GHz with 50 MHz bandwidth in a typical urban area of *** links constituting the relay transmission,i.e.,the link between base station and relay station,the link between relay station and mobile station and the link between base station and mobile station were measured by employing a real-time channel *** main factors that affect the MIMO channel capacity,i.e.,the channel gain and effective degrees of freedom,are *** cross-polarization discrimination was obtained by utilizing space-alternating generalized expectation-maximization *** channel parameters of the three links are statistically analyzed and *** the second step,based on the measured data,the performance of different relaying schemes,i.e.,amplify-and-forward and decode-and-forward,is *** impact of RS antenna configuration on the capacity is also *** measurement and evaluation results reveal that the relay can significantly improve the system coverage and performance.

关键词： MIMO relay channels IMT-advanced frequency band channel characteristics relay performance evaluation

Another ID-Based Proxy Signature Scheme and Its Extension

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Wuhan University Journal of Natural sciences 2007年第1期12卷 33-36页

作者： ZHANG Jianhong1,2 , ZOU Wei3 1. College of science, North china University of technology, beijing 10004.,china 2. Institute of Software of Chinese Academy of sciences /State key laboratory of information Security, beijing 100080, china 3. Institute of Computer science and technology, Peking University, beijing 100871, china College of science North China University of Technology Beijing China State key laboratory of information Security Institute of Software of Chinese Academy of Sciences Beijing China Institute of Computer science and technology Peking University Beijing China

So fur, the security of many proxy signatures has seldom been considered in a formal way and most of them cannot satisfy nonepudiation. In this work, a novel ID-based （Identity-based） proxy signature scheme is proposed by combining the proxy signature with ID-based public cryptography, and they formalize the notion of security for ID-based proxy signature schemes. And show that the security of the proposed scheme is secure. Compured with other proxy signature schemes, it does not need a secure channel. Thus, it is particularly suitable for the unreliable network computation environment. Finally, they extend proposed scheme to a proxy multi-signature which has the following advantages （1） the size of proxy multi- signature is independent of the number of delegating users; （2） the computation cost of proxy multi-signature only need two Weil paring.

关键词： proxy signature multisignature security proof

Active-fault-alarm based pre-restoration mechanism in MPLS-TP optical network

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The Journal of china Universities of Posts and Telecommunications 2010年第3期17卷 97-103页

作者： BAI Hui-feng, LU Yue-ming, JI Yue-feng key laboratory of information Photonics and Optical Communications, Ministry of Education, beijing University of Posts and Telecommunications, beijing 100876, china [a] key laboratory of information Photonics Optical Communications Ministry of Education Beijing University of Posts Telecommunications Beijing 100876 China

The newly developed multi-protocol label switching transport profile （MPLS-TP） fails to actively alarm the fault in advance when conducting restoration in network, or to avoid the false-alarm when equipped with the active-fault-alarm （AFA） to support carrier-grade reliability. In order to solve this problem, a new AFA based pre-restoration mechanism （AFABPRM） is proposed for MPLS-TP controlled optical network, along with the three levels quality-of-service （QoS） based shortest path first rerouting algorithm （TQ-SPF） in this article. The AFABPRM takes full advantage of the AFA technologies, and can solve the false-alarm problem. Analytical and experimental results suggest the better performances of the new mechanism when compared restoration mechanism with or without AFA function, and show that the AFABPRM can solve the false-alarm problem efficiently.

关键词： MPLS-TP restoration AFA

Heuristic for no-wait flow shops with makespan minimization based on total idle-time increments

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science in china(Series F) 2008年第7期51卷 896-909页

作者： LI XiaoPing1,2 & WU Cheng3 1 School of Computer science & Engineering, Southeast University, Nanjing 210096, china 2 key laboratory of Computer network and information Integration (Southeast University), Ministry of Education, Nanjing 210096, china 3 Department of Automation, Tsinghua University, beijing 100084, china 1. School of Computer science & Engineering Southeast University Nanjing 210096 China 2. key laboratory of Computer network and information Integration (Southeast University) Ministry of Education Nanjing 210096 China 3. Department of Automation Tsinghua University Beijing 100084 China

No-wait flow shops with makespan minimization are classified as NP-hard. In this paper, the optimization objective is equivalently transformed to total idle-time minimization. The independence relationship between tasks is analyzed, and objective increment properties are established for the fundamental operators of the heuristics. The quality of the new schedules generated during a heuristic is judged only by objective increments and not by the traditional method, which computes and compares the objective of a whole schedule. Based on objective increments, the time complexity of the heuristic can be decreased by one order. A seed phase is presented to generate an initial solution according to the transformed objective. Construction and improvement phases are introduced by experimental analysis. The FCH （fast composite heuristic） is proposed and compared with the most effective algorithms currently available for the considered problem. Experimental results show that the effectiveness of the FCH is similar to that of the best methods but requires far less computation time. The FCH can also be efficient in real time scheduling and rescheduling for no-wait flow shops.

关键词： no-wait flow shops heuristic makespan Tabu search

A study on correlativity between Qinghai-Tibet Plateau thermal infrared remote sensing data and underground temperature

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science china(Technological sciences) 2006年第z2期49卷 114-120页

作者： HAN Liqun, BI Siwen & SONG Shixin School of information Engineering, beijing technology and Business University, beijing 100037, china key laboratory of Remote Sensing information sciences, Institute of Remote Sensing Applications, Chinese Academy of sciences, beijing 100101, china beijing Technol & Business Univ Sch Informat Engn Beijing 100037 Peoples R China Chinese Acad Sci Inst Remote Sensing Applicat Key Lab Remote Sensing Informat Sci Beijing 100101 Peoples R China

Based on an analysis of the correlativity between Qinghai-Tibet Plateau thermal infrared remote sensing data (QPTIRSD) and underground temperature field distribution, the main factors which obviously influence underground-layer temperatures were derived. Using neural network technology, a model was built to compute underground temperatures via parameters out of the inversion of thermal infrared remote sensing (TIRS) and then analyze the correlativity between above-ground parameters and underground temperatures. This method offers a new way to apply TIRS in monitoring the suture zone of a large-area massif as well as to research structural thermal anomalies.

关键词： Qinghai-Tibet Plateau, TIRS, artificial neural network, temperature.

Communication network designing:Transmission capacity,cost and scalability

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science china(information sciences) 2012年第11期55卷 2454-2465页

作者： ZHANG GuoQiang1,2,3 & ZHANG GuoQing1 1Institute of Computing technology,Chinese Academy of sciences,beijing 100190,china 2School of Computer science and technology,Nanjing Normal University,Nanjing 210046,china 3Provincial key laboratory for Computer information Processing technology,Soochow University,Suzhou 215000,china 1. Institute of Computing technology Chinese Academy of Sciences Beijing 100190 China2. School of Computer Science and Technology Nanjing Normal University Nanjing 210046 China3. Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215000 China

Despite the growing number of works centering around the traffic dynamics on complex networks,these researches still have some common shortcomings,e.g.,too simple traffic flow model and lack of considerations for the designing cost and scalability *** paper builds on a more realistic traffic flow model,and offers a holistic view on the network designing *** addition to the extensively studied transmission capacity,this paper takes designing cost and scalability as two other designing objectives,and presents a quantitative study of how different designing choices independently and collectively influence these objectives by the introduction of a cartesian coordinate *** is shown that different kinds of network topologies display different shapes of achievable solution spaces and exhibit different abilities to achieve cost-effective and scalable *** particular,we find the philosophy underlying empirical network designing and engineering today fails to meet the cost-effective and scalable designing requirements,and propose a cost-effective and scalable designing scheme for BA-like networks,i.e.,the efficient routing combined with effective betweenness based link bandwidth *** addition,when designing a thoroughly new network from the beginning,we find that ER network is a good candidate to achieve cost-effective and scalable designing in most settings.

关键词： cost-effective communication network designing network transmission efficiency network topology traffic dynamics next generation network scalable network designing