摘要
对于连通图G,矩阵Q(G)=D(G)+A(G)称为图G的拟拉普拉斯矩阵,其中D(G)为图的度对角矩阵,A(G)为图的邻接矩阵.本文利用矩阵的一些性质,推导出连通图的拟拉普拉斯谱半径的一个上界.并将该上界与已有的一些结论结合具体图例作了优越性比较.
Let G be a connected graph, its quasi-Laplacian matrix is Q(G) =D(G) +A( G), where D(G) is the diagonal matrix of its vertex degrees and A (G) is its adjacency matrix. Using some properties of matrix, a sharp upper bound on the quasi-Laplacian spectral radius of connected graphs is obtained, and the superiority of the upper bound is compared with other bounds through some graphs.
出处
《南京师大学报(自然科学版)》
CAS
CSCD
北大核心
2008年第2期27-30,共4页
Journal of Nanjing Normal University(Natural Science Edition)
基金
国家自然科学基金(10671095)
南京信息工程大学科研基金资助项目
关键词
连通图
拟拉普拉斯矩阵
特征值
谱半径
度序列
connected graphs, quasi-Laplacian matrix, eigenvalue, spectral radius, degree sequence