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Bandwidth allocation and admission control scheme based on Nash bargaining solution for WiMAX systems

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The Journal of China Universities of posts and telecommunications 2010年第2期17卷 53-58页

作者： CAI Dao-jin ,JI Hong,LI Xi Key Laboratory of Universal Wireless Communications,Ministry of Education,beijing university of posts and{3.,beijing 100876,China Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Development of fair and efficient bandwidth allocation and admission control schemes is one of the key issues in the design of IEEE 802.16 broadband wireless access systems in time division multiple access （TDMA） mode. In this article, the problem of bandwidth allocation and admission control is formulated as a Nash bargaining model. The nash bargaining solution （NBS） derived from the cooperative game is adopted to maximize the spectrum utilization. Analysis and simulation results show that there is a unique Pareto optimal bandwidth allocation solution by using NBS among various flows. Furthermore, maximum utility of the system can also be maintained by using the admission control policy with different number of connections and variable channel qualities. The total throughput of the proposed scheme is close to the maximal one, while significantly improving fairness compared to the existing solutions.

关键词： NBS game theory bandwidth allocation admission control IEEE 802.16

Automatic composition of information-providing web services based on query rewriting

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science China(Information sciences) 2012年第11期55卷 2428-2444页

作者： ZHAO WenFeng,LIU ChuanChang & CHEN JunLiang State Key Laboratory of Networking and Switching Technology,beijing university of posts and{3.,beijing 100876,China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

Compared with normal web services,information-providing services have unique features that have seldom been considered in existing research on the automatic composition of web *** this paper,we present a simple,yet well-formed,semantic-based capability model for information-providing web services,which can express such features as not modifying the world state and not requiring all input/output parameters to be supplemented with class information as *** then present a corresponding automatic composition method derived from a query rewriting algorithm,MiniCon,used in the data integration *** method adequately utilizes previous features,enables primitive semantic reasoning,and can generate executable BPEL scripts *** of the method is complementary to traditional search-based *** on a typical type of problem show that the method is usable in practice.

关键词： web services automatic composition query rewriting data integration ontology semantic web

Photoionization Cross Section and Resonance Structure of Mn+

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Communications in Theoretical Physics 2006年第5期45卷 911-913页

作者： LU Peng-Fei,~1 LIU Jin-Chao,~2 and YANG Xiang-Dong~2 ~1 school of science, beijing{3. of posts and Telecommunication, beijing 100876, China ~2 Institute of Atomic and Molecular Physics, Sichuan{3., Chengdu 610065, China school of science Beijing University of Posts and Telecommunication Beijing 100876 China Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

A photoionization cross section calculation of Mn;is performed in the formalism of many-body perturbation theory for photon energies ranging from 48 eV to 56 eV. We consider excitations from the 3., 3., and 4s subshells. The effects of the strong 3.→3. and 3.→4s transitions are included as resonant contributions to the total cross sections. Good agreement with experiment is found.

关键词： many-body perturbation theory effective single-particle potential generalized resonance method

On-demand coding-aware routing in wireless Mesh networks

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The Journal of China Universities of posts and telecommunications 2010年第5期17卷 80-86,92页

作者： SUN Jian-zhen,LIU Yuan-an,HU He-fei,YUAN Dong-ming Wireless Communications and EMC Laboratory,beijing university of posts and{3.,beijing 100876,China Wireless Communications and EMC Laboratory Beijing University of Posts and Telecommunications Beijing 100876 China

Network coding,which exploits the broadcast nature of wireless medium,is an effective way to improve network performance in wireless multi-hop networks,but the first practical wireless network coding system COPE cannot actively detect a route with more coding opportunities and limit the coding structure within two-hop *** on-demand coding-aware routing scheme （OCAR） for wireless Mesh networks is proposed to overcome the limitations specified above by actively detecting a route with more coding opportunities along the entire route rather than within two-hop *** more coding opportunities tends to route multiple flows ‘close to each other’ while avoiding interference requires routing multiple flows ‘away from each other’.OCAR achieves a tradeoff by adopting RC AIA as routing metric in route discovery,which is not only coding-aware but also considers both inter and intra flow *** results show that,compared with Ad-hoc on-demand distance vecfor routing （AODV） and AODV＋COPE,OCAR can find more coding opportunities,thus effectively increase network throughput,reduce end to end delay and alleviate network congestion.

关键词： Mesh networks network coding coding-aware routing protocol

Rhythm dynamics of complex neuronal networks with mixed bursting neurons

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Chinese Physics B 2013年第4期22卷 167-171页

作者：吕永兵石霞郑艳红 school of science Beijing University of Posts and Telecommunications school of Mathematics and Computer science Fujian Normal University

The spatiotemporal order and rhythm dynamics of a complex neuronal network with mixed bursting neurons are studied in this paper. A quantitative characteristic, the width factor, is introduced to describe the rhythm dynamics of an individual neuron, and the average width factor is used to characterize the rhythm dynamics of a neuronal network. An r parameter is introduced to denote the ratio of the short bursting neurons in the network. Then we investigate the effect of the ratio on the rhythm dynamics of the neuronal network. The critical value of r is derived, and the neurons in the network always remain short bursting when the r ratio is larger than the critical value.

关键词： rhythm dynamics complex network neuron

Modified chaotic ant swarm to function optimization

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The Journal of China Universities of posts and telecommunications 2009年第1期16卷 58-63页

作者： LI Yu-ying , WEN Qiao-yan, LI Li-xiang State Key Laboratory of Networking and Switching Technology, beijing university of posts and telecommunications, beijing 100876, China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

The chaotic ant swarm algorithm （CAS） is an optimization algorithm based on swarm intelligence theory, and it is inspired by the chaotic and self-organizing behavior of the ants in nature. Based on the analysis of the properties of the CAS, this article proposes a variation on the CAS called the modified chaotic ant swarm （MCAS）, which employs two novel strategies to significantly improve the performance of the original algorithm. This is achieved by restricting the variables to search ranges and making the global best ant to learn from different ants＇ best information in the end. The simulation of the MCAS on five benchmark functions shows that the MCAS improves the precision of the solution.

关键词： chaotic ant swarm benchmark functions modified chaotic ant swarm swarm intelligence

Simulation of moving boundary of the reaction shaft in a flash smelting furnace

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Journal of Central South university 2001年第3期13卷 213-218页

作者： CHEN Zhuo 1,MEI Chi 1,CHEN Hong-rong 1,MO Jiao 2 (1 Institute on Simulation and Optimization of Pyro-installation, Central Sout h university, Changsha 410083. China 2 science school,{3., beijing 1 Institute on Simulation and Optimization of Pyro-installation Central South University Changsha China science school Beijing University of Posts and Telecommunications Beijing China

As to solve the online monitoring of the inner temperatur e and freezing profile of the reaction shaft of flash smelting furnace, simulation of the wall in the reaction shaft in a flash smelting furnace was made through numerical computation. The computational results are very near the data got in s ite. The error of the moving boundary is approximately 3., and that of the tempe rature is less than 5%. It is proved that the simulation software is applicable for practice to monitor the temperature and moving boundary inside the hearth on line. Based on a large number of the data computed, the relation between the cha nge of the moving boundary and inner temperature is summarized, and the great in fluence of the cooling system on the forming and stability of the moving boundar y inside the hearth is emphasized, which provide the theoretical bases for optim izing the flash smelting operation.

关键词： flash smelting furnace moving boundary numerical computation simulation

Symbolic Computation Study of (2+1)-Dimensional Dispersive Long Wave Equations

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Communications in Theoretical Physics 2006年第8期46卷 199-202页

作者： LU Zhuo-Sheng~(1,2,+) and XIE Fu-Ding~(2,3. ~1school of science, beijing{3. of Post and telecommunications, beijing 100876, China ~2Key Laboratory of Mathematics Mechanization, Academy of Mathematics and System sciences, the Chinese Academy of sciences, beijing 100080, China ~3.epartment of Computer science, Liaoning Normal{3., Dalian 116029, China school of science Beijing University of Post and Telecommunications Beijing 100876 China Key Laboratory of Mathematics Mechanization Academy of Mathematics and System Sciences the Chinese Academy of Sciences Beijing 100080 China Department of Computer science Liaoning Normal University Dalian 116029 China

Seeking exact analytical solutions of nonlinear evolution equations is of fundamental importance in mathematical physics. In this paper, based on a constructive algorithm and symbolic computation, abundant new exact solutions of the (2+1)-dimensional dispersive long wave equations are obtained, among which there are soliton-like solutions, mult-soliton-like solutions and formal periodic solutions, etc. Certain special solutions are considered and some interesting localized structures are revealed.

关键词： dispersive long wave equations symbolic computation exact solution localized structure

Digital Rights Management：Model,Technology and Application

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China Communications 2017年第6期14卷 156-167页

作者： Zhaofeng Ma school of Cyberspace Security Beijing University of Posts and Telecommunications Beijing 100876 China

with rapid achievement of current information technology and computing ability and applications,much more digital content such as films,cartoons,design drawings,office documents and software source codes are produced in daily work,however to protect the content being copying,shared or deliberately stolen by inside or outside,digital rights management(DRM) became more and more important for digital content *** this paper,we studied various DRM model,technology and application,and first proposed DRM Security Infrastructure(DSI),in which we defined encryption,hash,signature algorithm,watermarking algorithms,authentication,usage control,trusted counter,conditional trace,secure payment,and based on the DSI we then proposed a whole classification approach and architecture of all kinds of DRMs,in which we proposed 6 typical classes of copyrights and content protection DRMs architecture:(1) Software-oriented DRM,(2) e Book-oriented DRM,(3. Video-oriented DRM,(4) Image-Oriented DRM(5) Unstructured data oriented DRM,(6) Text-oriented *** on the above DSI,we then proposed a dynamic DRM model selection method for various DRM application,which can be adapted dynamically for different technology of different applications,which can provide awhole solution for variant DRM development in a rapid and customized *** proposed DRM method,technology and application in this paper provided a common,flexible and extendable solution for variant DRM scenes,and can support rapid and customized ***,we proposed an opinion that the future life will enter into a new era that the content usage and consumption will not again adopt DRM technology rather than with law,liberty and morality.

关键词： digital rights management drm security infrastructure encryption watermark usage control drm-free