Journal of Applied Mathematics and Computing ( IF 2.2 ) Pub Date : 2020-09-11 , DOI: 10.1007/s12190-020-01433-5 H. Naresh Kumar , D. Pradhan , Y. B. Venkatakrishnan
In a graph \(G=(V,E)\), a vertex \(v\in V\) is said to ve-dominate the edges incident on v as well as the edges adjacent to these incident edges on v. A set \(D\subseteq V\) is called a double vertex-edge dominating set if every edge of the graph is ve-dominated by at least two vertices of D. Given a graph G, the double vertex-edge dominating problem, namely Min-DVEDS is to find a minimum double vertex-edge dominating set of G. In this paper, we show that the decision version of Min-DVEDS is NP-complete for chordal graphs. We present a linear time algorithm to find a minimum double vertex-edge dominating set in proper interval graphs. We also show that for a graph having n vertices, Min-DVEDS cannot be approximated within \((1 -\varepsilon ) \ln n\) for any \(\varepsilon > 0\) unless NP \(\subseteq \)DTIME(\(n^{O(\log \log n)}\)). On positive side, we show that Min-DVEDS can be approximated by a factor of \(O(\ln \varDelta )\). Finally, we show that Min-DVEDS is APX-complete for graphs with maximum degree 5.
中文翻译:
图形中的双顶点边缘控制:复杂性和算法
在图\(G =(V,E)\) ,顶点\(V \以V \)被说成已经-支配边缘入射v以及相邻的对这些事件的边缘边缘v。如果图的每个边都由D的至少两个顶点ve支配,则集合\(D \ subseteq V \)被称为双顶点边控制集。给定一个图G,双顶点边缘占优问题,即Min - DVEDS是找到G的最小双顶点边缘占优集。在本文中,我们表明对于弦图,Min - DVEDS的决策版本 是NP -complete。我们提出一种线性时间算法,以在适当的间隔图中找到最小的双顶点边控制集。我们还表明,对于具有n个顶点的图,除非NP \(\ subseteq \)DTIME,否则对于任何\(\ varepsilon> 0 \),Min - DVEDS 都不能在\((1- -varepsilon )\ ln n \)内近似。(\(n ^ {O(\ log \ log n)} \))。在积极的一面,我们表明,闽- DVEDS 可以通过倍近似 \(O(\ ln \ varDelta)\)。最后,我们证明对于最大度为5的图,Min - DVEDS 是APX -complete。