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REal SEQUENCES WITH GOOD AUTO-CORRELATION AND CROSS-CORRELATION

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Journal of Electronics(china) 1991年第1期8卷 68-76页

作者：杨义先 beijing university of posts and telecommunications Beijing

New classes of real sequences with good auto-correlation and cross-correlation areconstructed by using sinusoidal functions. The new sequences are better than the FZC and alltopsequences in two aspects: (1) lower corr... 详细信息

关键词： Communication theory Correlation functions Sequences

Generalized Distributed Multicell Architecture:Group Cell

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ZTE Communications 2006年第2期4卷 7-10页

作者： Tao Xiaofeng Wu Chunli Xu Xiaodong (WTI, beijing university of posts and telecommunications, beijing 100876, china)

In order to make full use of advanced technologies for future mobile communications systems such as Space Time Code (STC), Joint Transmission (JT) and Multiple Input Multiple Output (MIMO), and to meet the requirements of high-bit-rate multimedia services, new network topologies should be studied. Generalized distributed multicell architecture can take full advantage of multi-antenna technologies and solve the problem of frequent handover caused by higher carrier frequencies. Group handover, the handover policy based on the architecture, can eliminate the cell edge effect. Furthermore, by applying the concept of group handover to 3G mobile communication systems, the Fast Cell Group Selection (FCGS) scheme can effectively improve the data rate for cell edge users.

关键词： Figure cell IEEE Radio USA Generalized Distributed Multicell Architecture more GPP MT

Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

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science in china(Series F) 2009年第12期52卷 2415-2423页

作者： XU ChangLong1,3,4, YANG Wei1,2 & YE WeiChen4 1 State Key Laboratory of Networking and Switching Technology, beijing university of posts and telecommunications, beijing 100044, china 2 State Key Laboratory of Rail Traffic Control and Safety, beijing Jiaotong university, beijing 100044, china 3 National Mobile Communications Research Laboratory, Southeast university, Nanjing 210096, china 4 Intel Corporation, beijing Kerry Center, Guanghua Road 1, beijing 100020, china State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100044 China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Intel Corporation Beijing Kerry Center Guanghua Road 1 Beijing 100020 China

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

关键词： block code product code iterative decoding

A Survey of Pervasive Services

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ZTE Communications 2008年第1期6卷 29-32页

作者： Liao Jianxin (State Key Lab of Network and Switch Technology, beijing university of posts and telecommunications, beijing 100876, china)

With the technological advances and market development, telecommunications networks and the Internet are converging into one universal network; meanwhile, the services provided by these two kinds of networks are integrating. Pervasive services will meet demands and expectations from all aspects. The topic has become a favorite for research in Beyond Third Generation (B3G), Next Generation Network (NGN) and Next Generation Internet (NGI) fields. The concept of the pervasive services comes from pervasive computation and B3G. Their features include pervasiveness, mobility, transparency, QoS-guarantee, customization, adaptiveness, push, security, easiness, variety and time-to-market. 3GPP, OMA and the B3G research program of the European Union (EU) have conducted a lot of research work about the different features of pervasive services. The current hot topics in the pervasive services research include context awareness and service enabling.

关键词： GPP A Survey of Pervasive Services

AN ADAPTIVE TRUST REGION METHOD FOR EQUalITY CONSTRAINED OPTIMIZATION

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Journal of Systems science & Complexity 2003年第4期16卷 494-505页

作者： ZHANGJuliang ZHANGXiangstm ZHUOXinjian DepartmentofManagementscienceandEngineering SchoolofEconomicsandManagementTsinghuaUniversityBeijin9100084China InstituteofAppliedMathematics AcademyofMathematicsandSystemsSciencesChineseAcademyofSciencesBeijing100080China SchoolofInformationEngineering BeijingUniversityofPostsandTelecommunicationsBeijing100876China

In this paper, a trust region method for equality constrained optimizationbased on nondifferentiable exact penalty is proposed. In this algorithm, the trail step ischaracterized by computation of its normal component being separated from computation of itstangential component, i.e., only the tangential component of the trail step is constrained by trustradius while the normal component and trail step itself have no constraints. The other maincharacteristic of the algorithm is the decision of trust region radius. Here, the decision of trustregion radius uses the information of the gradient of objective function and reduced ***, Maratos effect will occur when we use the nondifferentiable exact penalty function as themerit function. In order to obtain the superlinear convergence of the algorithm, we use the twiceorder correction technique. Because of the speciality of the adaptive trust region method, we usetwice order correction when p = 0 (the definition is as in Section 2) and this is different from thetraditional trust region methods for equality constrained optimization. So the computation of thealgorithm in this paper is reduced. What is more, we can prove that the algorithm is globally andsuperlinearly convergent.

关键词： equality constrained optimization global convergence trust region method superlinear convergence nondifferentiable exact penalty function maratos effect

Information content security on the Internet:the control model and its evaluation

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science china(Information sciences) 2010年第1期53卷 30-49页

作者： FANG BinXing1, GUO YunChuan2,3 & ZHOU Yuan4 1School of Computer, beijing university of posts and telecommunications, beijing 100029, china 2Institute of Computing Technology, Chinese Academy of sciences, beijing 100190, china 3Graduate university of Chinese Academy of sciences, beijing 100049, china 4National Computer Network Emergency Response Technical Team/Coordination Center of china, beijing 100029, china 1. School of Computer Beijing University of Posts and Telecommunications Beijing 100029 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. National Computer Network Emergency Response Technical Team/Coordination Center of China Beijing 100029 China

Flooding of harmful information on the Internet seriously endangers the physiological and mental health of teenagers. Due to the user-friendliness of the Internet as well as the difficulty in the authentication for the access of specific categories of information, curbing the transmission of harmful information, i.e., assuring the information content security (ICS), has become a reasonable yet challenging alternative. At present, there is an urgent need to develop a systematic model that can effectively carry out the curbing. In fact, curbing the transmission of harmful information by way of filtering can be modeled by access control. In the paper, based on the three core-elements of communication, namely, "Who communicates with whom", "How do they communicate" and "What is the content of communication", we propose a control model, called ICCON. Unlike the existing access control, the reference monitor (RM) of our model is placed in the transmission channel, and moreover, an evaluation frame is proposed, through which the effectiveness of the RM in controlling information transmission on the Internet can be quantitatively evaluated.

关键词： content security access control quantitative evaluation

The Application of Graph Diffusion in High-level Feature Extraction

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

Cooperative Communication and Cognitive Radio (4)

2011 4th 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

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ZTE Communications 2009年第2期7卷 58-60页

作者： Luo Tao, Hao Jianjun, Yue Guangxin (beijing university of posts and telecommunications , beijing 100876 , P . R . china )

Cooperative communication and cognitive radio have become hot topics in recent research of communication networks, attracting a widespread attention. Cooperative communication technique can enhance the transmission capacity of a communication system, while cognitive radio technique can improve the spectrum utilization ratio. As a result, the combination of the two techniques will have a significant impact on the future wireless mobile communication system. This lecture comes in four parts. This part analyzes the impacts of cooperative communication technology on modern wireless communication systems.

关键词： Cooperative Communication and Cognitive Radio MIMO

Investing and Pricing with Supply Uncertainty in Electricity Market:A General View Combining Wholesale and Retail Market

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china Communications 2015年第3期12卷 20-34页

作者： LI Xiaobo GAO Li WANG Gongpu GAO Feifei WU Qingwei beijing university of posts and telecommunications School of Digital Media and Design Arts Beijing University of Posts and Telecommunications School of Computer and Information Technology Beijing Jiaotong University Department of Automation Tsinghua UniversityState Key Lab of Intelligent Technologies and SystemsTsinghua National Laboratory for Information Science and Technology(TNList)

Renewable energy,such as wind and solar energy,may vary signifi cantly over time and locations depending on the weather and the climate *** leads to the supply uncertainty in the electricity(power) market with renewable energy integrated to power *** this paper,electricity in the market is classified into two types:stablesupply electricity(SSE) and unstablesupply electricity(USE).We investigate the investment and pricing strategies under the electricity supply uncertainty in wholesale and retail electricity *** particular,our model combines the wholesale and retail market and capture the dominant players,i.e.,consumers,power plant(power operator),and electricity *** derive the market behaviors of these players,we formulate the market decision problems as a multistage Stackelberg *** solving the game model,we obtain the optimal,with closedform,wholesale investment and retail pricing strategy for the *** also obtain the energy supplier's best price mechanism numerically under certain *** fi nd the price of SSE being about 1.4 times higher than that of USE will benefi t energy supplieroptimally,under which power plant's optimal strategy of investing is to purchase USE about 4.5 times much more than SSE.

关键词： electricity supply with uncertainty electricity investment electricity pricing wholesale market retail market Stackelberg game