dc.contributor.author 缪惠芳 dc.contributor.author 郭晓峰 dc.date.accessioned 2017-11-14T02:50:33Z dc.date.available 2017-11-14T02:50:33Z dc.date.issued 2005-12-20 dc.identifier.citation 数学研究,2005,(04):5-11 dc.identifier.issn 1006-6837 dc.identifier.other SSYJ200504000 dc.identifier.uri https://dspace.xmu.edu.cn/handle/2288/154654 dc.description.abstract 对强连通有向图D的一个非空顶点子集S,D中包含S的具有最少弧数的强连通有向子图称为S的S teiner子图,S的强S teiner距离d(S)等于S的S teiner子图的弧数.如果S=k,那么d(S)称为S的k-强距离.对整数k 2和强有向图D的顶点v,v的k-强离心率sek(v)为D中所有包含v的k个顶点的子集的k-强距离的最大值.D中顶点的最小k-强离心率称为D的k-强半径,记为sradk(D),最大k-强离心率称为D的k-强直径,记为sd iamk(D).本文证明了,对于满足k+1 r,d n的任意整数r,d,存在顶点数为n的强竞赛图T′和T,″使得sradk(T)′=r和sd iamk(T)″=d;进而给出了强定向图的k-强直径的一个上界. dc.description.abstract For a nonempty vertex set S in a strong digraph D,the strong distance d(S) of S isthe minimum size(the number of edges) of a strong subdigraph of D containing the vertices of S.IfS contains k vertices,then d(S) is referred to as the k-strong distance of S.For an integer k 2 anda vertex v of a strong digraph D,the k-strong eccentricity sek(v) of v is the maximum k-strongdistance d(S) among all sets S of k vertices in D containing v.The minimum k-strong eccentricityamong the vertices of D is the k-strong radius of D sradk(D) and the maximum k-strong eccentricityis the k-strong diameter of D sdiamk(D).In this paper,we will show that for any integers r,d withk+1 r,d n,there exist strong tournaments T′and T″of order n such that sradk(T′)=r andsdiamk(T″)=d.And we also give an upper bound on the k-strong diameter of strong orientedgraphs. dc.description.sponsorship TheProjectSupportedbyNSFC(10331020) dc.language.iso zh_CN dc.subject 有向图 dc.subject 强距离 dc.subject 强半径 dc.subject 强直径 dc.subject Digraph dc.subject Strong distance dc.subject Strong radius dc.subject Strong diameter dc.title 强定向图的k-强距离(英文) dc.title.alternative On k-Strong Distance in Strong Oriented Graphs dc.type Article
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