数学季刊 ›› 2008, Vol. 23 ›› Issue (4): 475-479.

• •    下一篇

局部大边宽嵌入图的面圈和C-桥的结构

  

  1. Department fo Mathematics,East China Normal University

  • 收稿日期:2005-01-17 出版日期:2008-12-30 发布日期:2023-09-12
  • 作者简介:DENG Mo(1982-), male, native of Lanzhou, Gansu, a lecturer of Northwest China Normal University, M.S.D., engages in graph theory; REN Han(1958-), male, native of Wuhan, Hubei, a professor of East China Normal University, Ph.D., engages in topological graph theory; DONG Qian(1982-), female, native of Nanchang, Jiangxi, engages in graph theory.
  • 基金资助:
     Supported by NNSF of China(10271048,10671073); Supported by Science and Technology Commission of Shanghai Municipality(07XD14011); Supported by Shanghai Leading Academic Discipline Project(B407);

Structures of Facial Cycles and C-bridges of Embedded Graphs with Locally 

  1. Department fo Mathematics,East China Normal University

  • Received:2005-01-17 Online:2008-12-30 Published:2023-09-12
  • About author:DENG Mo(1982-), male, native of Lanzhou, Gansu, a lecturer of Northwest China Normal University, M.S.D., engages in graph theory; REN Han(1958-), male, native of Wuhan, Hubei, a professor of East China Normal University, Ph.D., engages in topological graph theory; DONG Qian(1982-), female, native of Nanchang, Jiangxi, engages in graph theory.
  • Supported by:
     Supported by NNSF of China(10271048,10671073); Supported by Science and Technology Commission of Shanghai Municipality(07XD14011); Supported by Shanghai Leading Academic Discipline Project(B407);

摘要: In this paper, we show that for a locally LEW-embedded 3-connected graph G in orientable surface, the following results hold:1) Each of such embeddings is minimum genus embedding;2) The facial cycles are precisely the induced nonseparating cycles which implies the uniqueness of such embeddings;3) Every overlap graph O(G,C) is a bipartite graph and G has only one C-bridge H such that CUH is nonplanar provided C is a contractible cycle shorter than every noncontractible cycle containing an edge of C. This extends the results of C Thomassen’s work on LEW-embedded graphs. 

关键词:  (locally)LEW-embedding; , C-bridge; , overlap , graph

Abstract: In this paper, we show that for a locally LEW-embedded 3-connected graph G in orientable surface, the following results hold:1) Each of such embeddings is minimum genus embedding;2) The facial cycles are precisely the induced nonseparating cycles which implies the uniqueness of such embeddings;3) Every overlap graph O(G,C) is a bipartite graph and G has only one C-bridge H such that CUH is nonplanar provided C is a contractible cycle shorter than every noncontractible cycle containing an edge of C. This extends the results of C Thomassen’s work on LEW-embedded graphs. 

Key words:  (locally)LEW-embedding; , C-bridge; , overlap , graph

中图分类号: