Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes t...Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes the one of a chain.As a consequence,the average and median distances in any such network are smaller than or equal to those of a chain.Research limitations:We restricted our investigations to undirected,unweighted networks.Practical implications:We are convinced that these results are useful in the study of small worlds and the so-called six degrees of separation property.Originality/value:To the best of our knowledge our research contains new network results,especially those related to frequencies of distances.展开更多
Objective:To explore how to choose the center locations to build the medical and health supplies reserve among many island towns.Methods:The center locations were selected from 18 towns Hainan Province,it's maximu...Objective:To explore how to choose the center locations to build the medical and health supplies reserve among many island towns.Methods:The center locations were selected from 18 towns Hainan Province,it's maximum service range(distance)was required to reach the minimum,or to minimize.Results:Three scenarios were considered,the center locations included only one town,two towns,three towns.By the use of graph theory and MATLAB programming,a mathematical model was established to obtain the shortest distance and the shortest path between arbitrary two towns.Conclusions:We find out the center sites under certain conditions,and determine the specific service ranges of the center sites.展开更多
云服务器端的数据始终面临着巨大的安全威胁。提出一种云环境下图数据中带边权重的隐私保护方法 HEPP-GD(Homomorphic Encryption for Privacy Protect in Graph Data)。HEPP-GD采用Paillier同态加密体系对图数据的边权重进行加密,在云...云服务器端的数据始终面临着巨大的安全威胁。提出一种云环境下图数据中带边权重的隐私保护方法 HEPP-GD(Homomorphic Encryption for Privacy Protect in Graph Data)。HEPP-GD采用Paillier同态加密体系对图数据的边权重进行加密,在云服务器端计算图数据中顶点之间的最短距离,这样边权重隐私信息将不会被非法的获取,本地客户端保存自己的密钥使得加密后的信息在因特网上传输。建立了HEPP-GD实验环境.测试结果表明,在云服务器端的大规模的图数据情况下,HEPP-GD隐私保护方法可以利用很少的内存资源完成最短路径距离的计算,其安全性通过Paillier加密得到了保证。展开更多
文摘Purpose:To contribute to the study of networks and graphs.Design/methodology/approach:We apply standard mathematical thinking.Findings:We show that the distance distribution in an undirected network Lorenz majorizes the one of a chain.As a consequence,the average and median distances in any such network are smaller than or equal to those of a chain.Research limitations:We restricted our investigations to undirected,unweighted networks.Practical implications:We are convinced that these results are useful in the study of small worlds and the so-called six degrees of separation property.Originality/value:To the best of our knowledge our research contains new network results,especially those related to frequencies of distances.
基金National Natural Science Foundation(81060160)National Natural Science Foundation(71263014)+1 种基金Natural Science Foundation of Hainan Province(811209)Natural Science Foundation of Hainan Province(110005)
文摘Objective:To explore how to choose the center locations to build the medical and health supplies reserve among many island towns.Methods:The center locations were selected from 18 towns Hainan Province,it's maximum service range(distance)was required to reach the minimum,or to minimize.Results:Three scenarios were considered,the center locations included only one town,two towns,three towns.By the use of graph theory and MATLAB programming,a mathematical model was established to obtain the shortest distance and the shortest path between arbitrary two towns.Conclusions:We find out the center sites under certain conditions,and determine the specific service ranges of the center sites.
文摘云服务器端的数据始终面临着巨大的安全威胁。提出一种云环境下图数据中带边权重的隐私保护方法 HEPP-GD(Homomorphic Encryption for Privacy Protect in Graph Data)。HEPP-GD采用Paillier同态加密体系对图数据的边权重进行加密,在云服务器端计算图数据中顶点之间的最短距离,这样边权重隐私信息将不会被非法的获取,本地客户端保存自己的密钥使得加密后的信息在因特网上传输。建立了HEPP-GD实验环境.测试结果表明,在云服务器端的大规模的图数据情况下,HEPP-GD隐私保护方法可以利用很少的内存资源完成最短路径距离的计算,其安全性通过Paillier加密得到了保证。
