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Two-Level Unequal Error Protection Scheme in Image Transmission System Using Multilevel Codes in Rayleigh Fading Channel

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The Journal of China Universities of posts and telecommunications 2004年第z1期11卷 55-61页

作者： LI Zuo-wei~1, YANG Yi-xian~1, YUAN Dong-feng~2, HU Zheng-ming~1 1.Information Security Center,beijing university of posts and telecommunications,{4., P.R. China 2.school of Information science and Engineering, Shandong university, Jinan 250100, P.R. China Information Security Center Beijing University of Posts and Telecommunications Beijing 100876 P.R. China school of Information science and Engineering Shandong University Jinan 250100 P.R. China

In this paper, we propose a novel Unequal Error Protection (UEP) scheme with two levels for image transmission using Multilevel Codes (MLC). By providing the best protection for the most important data, the final recovered image quality is remarkably improved both in visual effect and in Peak Signal to Noise power Ratio (PSNR) performance.

关键词： rayleigh fading channel image transmission inequal error protection multilevel coding

维普期刊数据库

The Application of Graph Diffusion in High-level Feature Extraction

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The Application of Graph Diffusion in High-level Feature Ext...

2011 4.h IEEE International Conference on Computer science and Information Technology(ICCSIT 2011)

作者： Xiaohan Du school of Information and Communication Engineering beijing university of posts and telecommunications beijing China 100876 Honggang Zhang school of Information and Communication Engineering beijing university of posts and telecommunications beijing China 100876

In this paper,a new graph diffusion method is presented to improve the high-level feature extraction *** this method,we construct a semantic graph by describe the concepts as nodes and the concept affinities as the weights of edges,then we use the training set and its corresponding label matrix to estimate the concept relationship,where the relationship of two concepts were measured by the inner product of its corresponding row *** test the method on the high-level feature extraction task of TRECVID 2009 and the experimental results show the effectiveness of the method.

关键词： high-level feature extraction inner product graph diffusion,image retrieval

Designing of a Web-based RCS Service System

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Designing of a Web-based RCS Service System

2010 IEEE 2nd Symposium on Web Society

作者： Xiaoqing You beijing university of posts and telecommunications,beijing 100876,China Ke Xu beijing university of posts and telecommunications,beijing 100876,China

＜正＞With the development of the information technology,the network offers more and more convenient service to people’s ***,the demand for integrated service is increasingly strong in this service-oriented *** this paper complicated network communica-tions services are *** an integrated service standard proposed by GSMA- RCS is ***,a simple Web-based RCS service system is designed in the paper.

关键词： RCS service science service system

Wireless Mesh Architecture for IP-Based Base Stations

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ZTE Communications 2008年第2期 15-19页

作者： Tian Hui, Tao Xiaofeng (beijing university of posts and telecommunications,{4., China)

Combining the performance advantages of both Wireless Local Area Network (WLAN) and Ad hoc network, Wireless Mesh Network (WMN) is characterized by large capacity, high rate and wide coverage. It has become an effective means for broadband wireless access and can be applied flexibly in various wireless environments. The wired connections between base stations in traditional cellular mobile communications systems can no longer satisfy the requirements for flexible deployment, low cost, high scalability and good reliability. The wireless Mesh architecture for IP-based base stations is thus introduced as an optional solution to support the flat and simplified next generation mobile communications networks. The key technologies used to support self-organization of IP-based base stations involve several aspects, including on-demand self-organization of base stations, joint radio resource scheduling mechanism, routing, security and network management.

关键词： Mesh Wireless Mesh Architecture for IP-Based Base Stations WMN IP

A New Image Process CNN

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A New Image Process CNN

中国运筹学会第七届学术交流会

作者： Zhuo Xinjian school of Information Engineering, beijing university of posts and,{4., beijing,100876, China

A set of cellular neural network (CNN) templates are proposed. ThisCNN can change each black pixel into thite and vice-versa, and translate the changedimages in each of 8 compass directions at the same time, respectively Robustnessanalysis gives template parameter inequalities which guarantee the correspondingCNN working well for performing prescribed tasks. Simulation examples are given.

关键词： cellular neural network(CNN) bobustness translation

Research on Trilateral Game among Owner,Contractor and Engineering Supervisor in Communication Construction Market

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Research on Trilateral Game among Owner,Contractor and Engin...

2010 Chinese Control and Decision Conference

作者： Yumei Zhao~1,Rong Hua~2,Xiaodong Zhang~3,Yaxian Li~4.1.school of Economics and Management,beijing university of posts&{4.,beijing,100876 2.school of Economics and Management,beijing university of posts&{4.,beijing,100876

＜正＞This paper combines principal-agent theory with rent-seeking theory,comprehensively analyzes the relationships among owner,supervisor and contractor,utilizes game theory to establish the model of owners,supervisor and contractor,and analyzes the game behavior or rent-seeking between supervisor and *** paper adds the long-term economic benefits and reputation of supervisor and contractor into the tripartite game model,and proposes some constructive comments.

关键词： Rent-seeking Risk Management Trilateral Game Communication Construction market

Key MAC Layer Technologies of Cognitive Radio Network

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ZTE Communications 2009年第2期7卷 21-26页

作者： Zeng Zhimin, Guo Caili (school of Information and Communication Engineering , beijing university of posts and telecommunications , beijing 100876 , P . R . China )

As a smart spectrum sharing technology, Cognitive Radio (CR) is becoming a hot topic in the field of wireless telecommunications. Besides providing traditional services, the cognitive radio network Media Access Control (MAC) layer is required to perform an entirely new set of functions for effective reusing spectrum opportunity, without causing any harmful interference to incumbents. Spectrum sensing management selects and optimizes sensing strategies and parameters by the selection of sensing mode, sensing period, sensing time, sensing channel, and sensing quiet period. Access control avoids collision with primary users mainly by cooperation access and transparent access. Dynamic spectrum allocation optimizes the allocation of uncertain spectrum for binary interference model and accumulative interference model. Security mechanism adds authentication and encryption mechanisms to MAC frame to defense MAC layer security attacks. Cross-layer design combines MAC layer information with physical layer or higher layers information, such as network layer, transmission layer, to achieve global optimization.

关键词： MAC Key MAC Layer Technologies of Cognitive Radio Network Radio

维普期刊数据库

The Algorithm and Its Application of a Multi-Channel Adaptive Decision-Feedback Equalizer

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The Journal of China Universities of posts and telecommunications 2003年第4期10卷 59-64页

作者： ZHANG Yu-liang,WU Wei-ling,TIAN Bao-yu,HE Zhi-qiang,GU Xin-yu(school of Information Engineering, beijing university of posts & {4., beijing 100876, P.R.China) school of Information Engineering Beijing University of Posts & Telecommunications 北京 100876

In digital radio communication, diversity reception can combat flat fadingand adaptive equalization can combat Inter-Symbol Interference (ISI). In this paper, the structureand algorithm of a multi-channel equalizer with combined diversity reception and adaptiveequalization techniques are studied. Because Phase-Looked-Loops (PLL) are embedded in the equalizer,this equalizer is suitable for coherent communication in channels with high phase *** Carlo simulation is used to test its performance and the results show that a multi-channeldecision-feedback-equalizer has better performance than a single-channeldecision-feedback-equalizer, and the results of processing high-speed digital underwatercommunication signals demonstrate this farther.

关键词： multi-channel decision-feedback-equalizer diversity reception coherentcommunications

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Construction Environment of Personal Handy Phone System and It’s Management

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Construction Environment of Personal Handy Phone System and ...

IEEE 2005 International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications

作者： Cui Xiaoyan school of Automation, beijing university of posts and telecommunications, 100876 China

Personal handy phone system is a populartelecommunication system to citizens. However, with theawakening of citizens’ environmental sense, theelectromagnetic radiation problem caused by the basestatio

关键词： personal handy phone, electromagneticradiation, environmental management