上海大学学报(自然科学版) ›› 2009, Vol. 15 ›› Issue (3): 272-275.

• 数理化科学 • 上一篇    下一篇

图的全符号局部控制数

段铸荣1 高明晶2 高瑞平2   

  1. 1.上海大学 理学院,上海 200444; 2.河北科技师范学院 数理系,河北 秦皇岛 066004
  • 收稿日期:2008-03-05 出版日期:2009-06-30 发布日期:2009-06-30
  • 通讯作者: 段铸荣(1982~),女,硕士研究生,研究方向为图论及组合最优化. E-mail:zhurong_1205@hotmail.com

Total Signed Local Domination Number in Graphs

 DUAN Zhu-Rong-1, GAO Meng-Jing-2, GAO Rui-Beng-2   

  1. 1.College of Sciences, Shanghai University, Shanghai 200444, China; 2.Department of Mathematics and Physics, Hebei Normal University of Science and Technology, Qinhuangdao 066004, Hebei, China
  • Received:2008-03-05 Online:2009-06-30 Published:2009-06-30

摘要:

考虑图G=(V,E)均为不含有孤立点的有限简单连通图. f是一个从V∪E→{-1,1}的函数,记f的权为ω(f)=∑〖DD(X〗x∈V∪E〖DD)〗 f(x),对V∪E中任一元素x,定义f[x]=∑〖DD(X〗y∈〖WTBX〗N〖WTBX〗T(x)〖DD)〗f(y), NT(x)表示与x关联边、相邻点的集合. 图G的全符号局部控制函数为f:V∪E→{-1,1}, 满足对所有的x∈V∪E有f[x]≥1. 图G的所有全符号局部控制函数中最小的权定义为G的全符号局部控制数,记作γTsl(G). 得到在一般图中全符号局部控制数的下界和完全二部图Km,n中的上界,并求出圈Cn中γTsl的精确值. 

关键词: 完全二部图;圈;全符号局部控制数;下界;上界

Abstract:

The graphs G=(V,E) considered here are finite, simple and without isolated vertices. For a function f:V∪E→{-1,1},weight of 〖WTBX〗f〖WTBZ〗 is ω(f)=∑〖DD(X〗x∈V∪E〖DD)〗 f(x). For each element 〖WTBX〗x〖WTBZ〗 in V∪E, we define f[x]=∑〖DD(X〗y∈〖WTBX〗N〖WTBX〗T(x)〖DD)〗f(y), where 〖WTBX〗NT〖WTBZ〗(〖WTBX〗x〖WTBZ〗) denotes adjacent and incident element of 〖WTBX〗x〖WTBZ〗. A total signed local dominating function (TSLDF) of 〖WTBX〗G〖WTBZ〗 is a function f:V∪E→{-1,1} so that f[x]≥1 for all x∈V∪E. The total signed local domination number of 〖WTBX〗G〖WTBZ〗 is the minimum weight of a TSLDF on 〖WTBX〗G〖WTBZ〗, denoted by γTsl(G). In this paper, some lower bounds in general graphs and an upper bound in complete bipartite graph 〖WTBX〗Km,n〖WTBZ〗 for γTsl, and the exact value on γTsl of cycle 〖WTBX〗Cn〖WTBZ〗 can be obtained.

Key words:  complete bipartite graph; cycle; total signed local domination number; lower bound; upper bound

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