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Communications in Theoretical Physics 2015年第7期64卷 95-102页

作者：陈时勇申可明代巍张本威张汉中王恩科 Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics Central China Normal University Physics Department Tsinghua University Key Laboratory of Quark & Lepton Physics (MOE)and Institute of Particle Physics Central China Normal University

By using the recent spatially dependent nuclear PDF set EPS09 s, we investigated the centrality-dependent Cold Nuclear Matter(CNM) effects for neutral π, η mesons and inclusive jets at RHIC in d+Au collisions and at LHC in p+Pb collisions. The nuclear modification factors as functions of transverse momentum are plotted at different centralities bins respectively. At all fixed centralities, the nuclear modification factors show no significant suppressions,contrast to the strong suppressions observed for central Au+Au collisions. Our results are consistent with the PHENIX preliminary Data in minimum bias and central d+Au collisions. The LHC experimental Data also support our predictions for both single inclusive hadron and inclusive jets productions in central p+Pb collisions. And the centrality dependence of the nuclear suppressions for all the observations in our calculations are lower than the RHIC and LHC Data.

关键词： centrality cold nuclear matter effects perturbativ

centrality,azimuthal and rapidity dependence of two-particle transverse-momentum correlation in relativistic heavy ion collisions

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Chinese Physics C 2009年第4期33卷 281-284页

作者：黄燕萍吴元芳 Institute of High Energy Physics CAS Institute of Particle Physics Huazhong Normal University

The centrality, azimuthal and rapidity dependence of two-particle transverse-momentum correlations are studied for Au-Au collision at 200 GeV using RQMD （relativistic quantum molecular dynamics） with and without final hadron re-scattering models. The influences of the re-scattering effects on the measured correlations are discussed. The results are compared with those from current heavy ion experiments.

关键词： centrality azimuthal rapidity transverse-momentum correlation.

Relative Degree Structural Hole centrality, CRD-SH: A New centrality Measure in Complex Networks

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Journal of Systems Science & Complexity 2019年第5期32卷 1306-1323页

作者： SOTOODEH Hamidreza FALAHRAD Mohammed Institute for Research in Fundamental Sciences(IPM) School of Computer ScienceTehranIran Qazvin Islamic Azad University Department of Computer EngineeringQazvinIran.

In order to assess influential nodes in complex networks, the authors propose a novel ranking method based on structural hole in combination with the degree ratio of a node and its neighbors. The proposed method is a response to the limitations of other proposed measures in this field. The structural hole gives a comprehensive attention of the information about the node topology in relation to its neighbors, whereas the degree ratio of nodes reflects its significance against the *** of the two aforementioned measures summarized in the structural hole leverage matrix demonstrates the importance of a node according to its position in the network structure. So a more accurate method for ranking influential nodes is established. The simulation results over different-scale networks(small networks with less than 30 nodes, medium networks with less than 150 nodes and large networks with more than 1000 nodes) suggest that the proposed method can rank important nodes more effectively and precisely in complex networks specifically in larger ones.

关键词： centrality measures complex networks influential nodes structural hole leverage matrix

Nodes and layers PageRank centrality for multilayer networks

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Chinese Physics B 2019年第2期28卷 129-136页

作者： Lai-Shui Lv Kun Zhang Ting Zhang Meng-Yue Ma Nanjing University of Science and Technology

In this paper, we propose a new centrality algorithm that can simultaneously rank the nodes and layers of multilayer networks, referred to as the MRFNL centrality. The centrality of nodes and layers are obtained by developing a novel iterative algorithm for computing a set of tensor equations. Under some conditions, the existence and uniqueness of this centrality were proven by applying the Brouwer fixed point theorem. Furthermore, the convergence of the proposed iterative algorithm was established. Finally, numerical experiments on a simple multilayer network and two real-world multilayer networks(i.e., Pierre Auger Collaboration and European Air Transportation Networks) are proposed to illustrate the effectiveness of the proposed algorithm and to compare it to other existing centrality measures.

关键词： multilayer networks PageRank centrality random walks transition probability tensors

Vertex centrality of complex networks based on joint nonnegative matrix factorization and graph embedding

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Chinese Physics B 2023年第1期32卷 634-645页

作者：卢鹏丽陈玮 School of Computer and Communication Lanzhou University of TechnologyLanzhou 730050China

Finding crucial vertices is a key problem for improving the reliability and ensuring the effective operation of networks,solved by approaches based on multiple attribute decision that suffer from ignoring the correlation among each attribute or the heterogeneity between attribute and structure. To overcome these problems, a novel vertex centrality approach, called VCJG, is proposed based on joint nonnegative matrix factorization and graph embedding. The potential attributes with linearly independent and the structure information are captured automatically in light of nonnegative matrix factorization for factorizing the weighted adjacent matrix and the structure matrix, which is generated by graph embedding. And the smoothness strategy is applied to eliminate the heterogeneity between attributes and structure by joint nonnegative matrix factorization. Then VCJG integrates the above steps to formulate an overall objective function, and obtain the ultimately potential attributes fused the structure information of network through optimizing the objective function. Finally, the attributes are combined with neighborhood rules to evaluate vertex's importance. Through comparative analyses with experiments on nine real-world networks, we demonstrate that the proposed approach outperforms nine state-of-the-art algorithms for identification of vital vertices with respect to correlation, monotonicity and accuracy of top-10 vertices ranking.

关键词： complex networks centrality joint nonnegative matrix factorization graph embedding smoothness strategy

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Analysis of city centrality based on entropy weight TOPSIS and population mobility:A case study of cities in the Yangtze River Economic Belt

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Journal of Geographical Sciences 2020年第4期30卷 515-534页

作者： LUO Jing CHEN Siyun SUN Xuan ZHU Yuanyuan ZENG Juxin CHEN Guangping Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province Central China Normal UniversityWuhan 430079China The College of Urban&Environmental Sciences Central China Normal UniversityWuhan 430079China Academy of Wuhan Metropolitan Area Hubei Provincial Development and Reform Commission/Central China Normal UniversityWuhan 430079China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China School of Earth Sciences Zhejiang UniversityHangzhou 310027China

Based on statistical data and population flow data for 2016,and using entropy weight TOPSIS and the obstacle degree model,the centrality of cities in the Yangtze River Economic Belt(YREB)together with the factors influencing centrality were *** addition,data for the population flow were used to analyze the relationships between cities and to verify *** results showed that:(1)The pattern of centrality conforms closely to the pole-axis theory and the central geography *** axes,corresponding to the Yangtze River and the Shanghai-Kunming railway line,interconnect cities of different *** the whole,the downstream cities have higher centrality,well-defined gradients and better development of city infrastructure compared with cities in the middle and upper reaches.(2)The economic scale and size of the population play a fundamental role in the centrality of cities,and other factors reflect differences due to different city *** most of the coastal cities or the capital cities in the central and western regions,factors that require long-term development such as industrial facilities,consumption,research and education provide the main competitive *** cities that are lagging behind in development,transportation facilities,construction of infrastructure and fixed asset investment have become the main methods to achieve development and enhance competitiveness.(3)The mobility of city populations has a significant correlation with the centrality score,the correlation coefficients for the relationships between population mobility and centrality are all greater than 0.86(Pcentrality and huge radiating effects of high-class ***,the cities in the YREB are closely linked to Guangdong and Beijing,reflecting the dominant economic status of Guangdong with its geographical proximity to the YREB and Beijing's e

关键词： city centrality entropy weight TOPSIS population mobility Yangtze River Economic Belt obstacle degree model

A measure of centrality based on modularity matrix

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Progress in Natural Science:Materials International 2008年第8期18卷 1043-1047页

作者： Gaoxia Wang, Yi Shen *, Enjie Luan The Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China The Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

In this paper, a kind of measure of structural centrality for networks, called modularity centrality, is introduced. This centrality index is based on the eigenvector belonging to the largest magnitude eigenvalue of modularity matrix. The measure is illustrated and compared with the standard centrality measures using a classic dataset. The statistical distribution of modularity centrality is investigated by considering large computer generated graphs and two networks from the real world.

关键词： centrality Modularity centrality Modularity matrix

Village Network centrality in Rural Tourism Destination:A Case from Yesanpo Tourism Area,China

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Journal of Mountain Science 2015年第3期12卷 759-768页

作者： ZHANG Rui-ying XI Jian-chao WANG Shou-kun WANG Xin-ge GE Quan-sheng Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Tianjin Agricultural University

With the development of rural tourism, the cooperation of villages has become very *** the status and importance of each village can contribute to better understanding of the integrated rural tourism management and sustainable rural tourism development. The research focused on 46 villages of Yesanpo scenic spot in China(39°35'-40°north latitude, and 115°16'- 115°30' east longitude). Integrating the method of Geographical Information System(GIS) and social network analysis, the spatial centrality and interrelation of each village in Yesanpo tourism destination were evaluated. The results showed that Xinggezhuang is the spatial core village of the whole 46 villages in Yesanpo tourism areas; Xinggezhuang, Nanzhuang, Zhenchang, Daze, Liujiahe and Zishikou are sub-core villages of the six tourism spots. Magezhuang, Ximagezhuang, Eyu, Zishikou, Daze, Shangzhuang, Zhenchang and Xiazhuang should be support of the core villages, which provide subsidiary services and connects with other nodes. The results also indicated that the study of the village centrality will contribute to build an integrated hierarchy structure and to provide sufficient basis for further development of rural tourism destination.

关键词： Network analysis centrality Ruraltourism Yesanpo

A centrality measure based on spectral optimization of modularity density

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Science China(Information Sciences) 2010年第9期53卷 1727-1737页

作者： FU LiDong1,2*,GAO Lin1 & MA XiaoKe1 1School of Computer Science and Engineering,Xidian University,Xi'an 710071,China 2College of Computer,Xi'an University of Science and Technology,Xi'an 710054,China 1. School of Computer Science and Engineering Xidian University Xi’an 710071 China2. College of Computer Xi’an University of Science and Technology Xi’an 710054 China

centrality analysis has been shown to be a valuable method for the structural analysis of complex *** is used to identify key elements within networks and to rank network elements such that experiments can be tailored to interesting *** this paper,we show that the optimization process of modularity density can be written in terms of the eigenspectrum of kernel *** on the eigenvectors belonging to the largest eigenvalue of kernel matrix,we present a new centrality measure that characterizes the contribution of each node to its assigned community in a network,called modularity density *** measure is illustrated and compared with the standard centrality measures by using respectively an artificial example and a classic network data *** statistical distribution of modularity density centrality is investigated by considering large computer generated graphs and two large networks from the real *** results show the significance of the proposed approach.

关键词： centrality modularity density centrality kernel matrix eigenspectrum

centrality Measures Based on Matrix Functions

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Open Journal of Discrete Mathematics 2018年第4期8卷 79-115页

作者： Lembris Laanyuni Njotto Department of Mathematics and ICT College of Business Education Dar Es Salaam Tanzania

Network is considered naturally as a wide range of different contexts, such as biological systems, social relationships as well as various technological scenarios. Investigation of the dynamic phenomena taking place in the network, determination of the structure of the network and community and description of the interactions between various elements of the network are the key issues in network analysis. One of the huge network structure challenges is the identification of the node(s) with an outstanding structural position within the network. The popular method for doing this is to calculate a measure of centrality. We examine node centrality measures such as degree, closeness, eigenvector, Katz and subgraph centrality for undirected networks. We show how the Katz centrality can be turned into degree and eigenvector centrality by considering limiting cases. Some existing centrality measures are linked to matrix functions. We extend this idea and examine the centrality measures based on general matrix functions and in particular, the logarithmic, cosine, sine, and hyperbolic functions. We also explore the concept of generalised Katz centrality. Various experiments are conducted for different networks generated by using random graph models. The results show that the logarithmic function in particular has potential as a centrality measure. Similar results were obtained for real-world networks.

关键词： Graph centrality Measures Matrix Functions Kendall Correlation Coefficient Random Graph Models