11月11日 王涛博士学术报告(数统学院)

文章作者:  发布时间: 2017-11-10  浏览次数: 10

报 告 人:王涛

报告题目:Paths and minor stars in some plane graphs

报告时间:2017年11月11日(周六)11:00

报告地点:静远楼204报告厅

主办单位:数学与统计学院、科技处

报告人简介:

    王涛,河南大学数学与统计学院,副教授。2009年6月获得南开大学博士学位。2013年9月--2014年9月,美国伊利诺伊大学香槟校区(UIUC)访问学者。目前主要研究图的染色问题。发表论文20篇,主持完成国家自然基金委数学天元项目和青年项目各一项。

报告摘要:

    The weight of a subgraph $H$ in $G$ is the sum of the degrees in $G$ of vertices of $H$. The height of a subgraph $H$ in $G$ is the maximum degree of vertices of $H$ in $G$. A star in a given graph is minor if its center has degree at most five in the given graph. Lebesgue (1940) gave an approximate description of minor $5$-stars in the class of normal plane maps with minimum degree five. We give two descriptions of minor $5$-stars in plane graphs with minimum degree five. By these descriptions, we can recover/improve several results and give some new results on the weight and height for some special plane graphs with minimum degree five. We also discuss stars and paths in graphs with bounded maximum average degree.