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degree distribution and robustness of cooperative communication network with scale-free model

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Chinese Physics B 2015年第6期24卷 115-121页

作者：王建荣王建萍何振许海涛 School of Computer and Communication Engineering University of Science and Technology Beijing

With the requirements of users enhanced for wireless communication, the cooperative communication will become a development trend in future. In this paper, a model based on complex networks with both preferential attachment is researched to solve an actual network CCN （Cooperative Communication Network）. Firstly, the evolution of CCN is given by four steps with different probabilities. At the same time, the rate equations of nodes degree are presented to analyze the evolution of CCN. Secondly, the degree distribution is analyzed by calculating the rate equation and numerical simulation. Finally, the robustness of CCN is studied by numerical simulation with random attack and intentional attack to analyze the effects of degree distribution and average path length. The results of this paper are more significant for building CCN to programme the resource of communication.

关键词： cooperative communication complex networks scale-free degree distribution robustness

degree distribution of a Scale-free Random Graph Model

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Acta Mathematica Sinica,English Series 2012年第3期28卷 587-598页

作者： Li TAN Zhen Ting HOU Xin Ru LIU School of Mathematics Central South University School of Traffic and Transportation Engineering Central South University

In this paper, we consider the degree distribution of a general random graph with multiple edges and loops from the perspective of probability. Based on the first-passage probability of Markov chains, we give a new and rigorous proof to the existence of the network degree distribution and obtain the precise expression of the degree distribution. The analytical results are in good agreement with numerical simulations.

关键词： degree distribution scale-free Markov chains

Performance of degree distribution based HARQ scheme for LDPC-coded OFDM system

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The Journal of China Universities of Posts and Telecommunications 2009年第1期16卷 47-50页

作者： LI Xue-hua CAO Yi-qing LI Zhen-song YANG Da-cheng Communication Engineering Department Beijing Information Science and Technology University Beijing 100101 China Wireless Theories and Technologies Lab (WT&T) Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies the degree distribution property of low density parity check （LDPC） codes by Gaussian approximation （GA） and presents an efficient hybrid automatic repeat quest （HARQ） scheme for LDPC-coded orthogonal frequency division multiplexing （OFDM） system. In the scheme, the important bits with large degrees have high retransmission priorities and are mapped to the sub-carriers with better channel quality indicator （CQI） levels in the OFDM system. The new scheme provides more protection to the bits with large degrees and thus contributes more to the decoding process by offering more transmission power. In this way the system performance would be improved. The statistics and simulation results also prove the new scheme.

关键词： LDPC codes HARQ degree distribution GA OFDM

The degree distribution of the Random Multigraphs

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Acta Mathematica Sinica,English Series 2012年第5期28卷 941-956页

作者： Ai Lian CHEN Fu Ji ZHANG Hao LI College of Mathematics and Computer Science Fuzhou University School of Mathematical Sciences Xiamen University Laboratoire de Recherche en Informatique UMR 8623C.N.R.S.-Universitde Paris-sud

In this paper, as a generalization of the binomial random graph model, we define the model of multigraphs as follows： let G（n; {pk}） be the probability space of all the labelled loopless multigraphs with vertex set V = {v1, v2, ..., vn }, in which the distribution of tvi,vj, the number of the edges between any two vertices vi and vj is P{tvi,vj =k}=Pk, k=0, 1,2,...and they are independent of each other. Denote by Xd = Xd（G）,Yd = Yd（G）, Zd = Zd（G） and Zcd = Zcd（G） the number of vertices of G with degree d, at least d, at most d and between c and d. In this paper, we discuss the distribution of Xd, Yd, Zd and Zcd in the probability space G（n; （Pk））.

关键词： degree distribution random multigraph degree sequence

THE STUDY ON degree distribution PROPERTY OF COMPLEX NETWORK BASED ON COOPERATIVE COMMUNICATION

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Journal of Electronics(China) 2010年第2期27卷 224-229页

作者： Xie Weihao Chen Huimin Yang Xiumei Xiong Yong Key Laboratory of Special Fiber Optics and Optical Access Networks Ministry of Education SCIE Shanghai University Shanghai 200072 China Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Complex networks have been widely studied. Recently,many results show that the degree distributions of some large networks follow the form of power-law and these networks possess better robustness against random nodes failure. As an effective technology on combating the channel fading,wireless cooperative communication is becoming one of the most important methods to improve the wireless communication performances. In this paper,the complex network models based on cooperative communication and non-cooperative communication are established; and the degree distribution properties for them are studied. The simulation results show that the degree distributions of these networks also follow the form of power-law,which means that the addition of cooperative communi-cation links will not change the property of degree distribution and then these networks will possess better robustness against random nodes failure as well.

关键词： Complex networks Cooperative communication degree distribution Power-law

Fast degree-distribution optimization for BATS codes

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Science China(Information Sciences) 2017年第10期60卷 124-138页

作者： Huakai ZHAO Shenghao YANG Guinian FENG Beijing Satellite Navigation Center The Chinese University of Hong Kong Beijing Institute of Tracking and Communication Technology

Batched sparse(BATS) codes have been proposed for communication through networks with packet loss. BATS codes include a matrix generalization of fountain codes as the outer code and random linear network coding at the intermediate network nodes as the inner code. BATS codes, however, do not possess a universal degree distribution that achieves an optimal rate for any distribution of the transfer matrix ranks. Therefore,it is important to have a fast degree-distribution optimization approach for finite-length BATS codes. In this paper, we propose the concept of batch release probability(BRP), and demonstrate some characteristics of BRPs from the degree distributions achieving nearly optimal performance. Based on these BRP characteristics,we propose a novel degree-distribution optimization approach that achieves the similar decoding performance with a much shorter optimization time, compared with the previous approach. Moreover, the universality of BRPs observed in this paper can further simplify the degree-distribution optimization of BATS codes.

关键词： network coding batched sparse(BATS) code finite-length analysis degree distribution batch release probability optimization

degree-distribution Stability of Evolving Networks

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Degree-Distribution Stability of Evolving Networks

Markov Chain-based degree distributions of Evolving Networks

第五届全国复杂网络学术会议

作者：孔祥星 School of Mathematics Central South University

In this paper,we study a class of stochastic processes,called evolving network Markov chains,in evolving *** approach is to transform the degree distribution problem of an evolving network to a corresponding problem of evolving network Markov *** investigate the evolving network Markov chains,thereby obtaining some exact formulas as well as a precise criterion for determining whether the steady degree distribution of the evolving network is a power-law or *** this new method,we finally obtain a rigorous,exact and unified solution of the steady degree distribution of the evolving network.

关键词： Evolving network Markov chain Scale-free network degree distribution

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Acta Mathematica Sinica,English Series 2012年第10期28卷 1981-1994页

作者： Xiang Xing KONG Zhen Ting HOU Ding Hua SHI Quan Rong CHEN Qing Gui ZHAO School of Mathematics Central South University Department of Mathematics Shanghai University Department of Electronic Engineering City University of Hong KongP.R.China Department of Mathematics and Science Hunan First Normal University

In this paper, we study a class of stochastic processes, called evolving network Markov chains, in evolving networks. Our approach is to transform the degree distribution problem of an evolving network to a corresponding problem of evolving network Markov chains. We investigate the evolving network Markov chains, thereby obtaining some exact formulas as well as a precise criterion for determining whether the steady degree distribution of the evolving network is a power-law or not. With this new method, we finally obtain a rigorous, exact and unified solution of the steady degree distribution of the evolving network.

关键词： Evolving network Markov chain scale-free network degree distribution

A novel evolving scale-free model with tunable attractiveness

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Chinese Physics B 2010年第7期19卷 35-39页

作者：刘绚刘天琪王昊李兴源 School of Electrical Engineering and Automation Sichuan University College of Electronics and Information Engineering Sichuan University

In this paper, a new evolving model with tunable attractiveness is presented. Based on the Barabasi-Albert （BA） model, we introduce the attractiveness of node which can change with node degree. Using the mean-field theory, we obtain the analytical expression of power-law degree distribution with the exponent γ∈ （3, ∞）. The new model is more homogeneous and has a lower clustering coefficient and bigger average path length than the BA model.

关键词： scale-free tunable attractiveness degree distribution clustering coefficient