Results 31 to 40 of about 166,020 (278)
Scientific Reports, 2021 Whenever some phenomenon can be represented as a graph or a network it seems pertinent to explore how much the mathematical properties of that network impact the phenomenon. In this study we explore the same philosophy in the context of immunology.
Arindam Banerjee +2 more
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Generalization of the Cover Pebbling Number for Networks
Frontiers in Physics, 2020 Pebbling can be viewed as a model of resource transportation for networks. We use a graph to denote the network. A pebbling move on a graph consists of the removal of two pebbles from a vertex and the placement of one pebble on an adjacent vertex.
Zheng-Jiang Xia, Zhen-Mu Hong
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Edge Dominating Sets and Vertex Covers
Discussiones Mathematicae Graph Theory, 2013 Bipartite graphs with equal edge domination number and maximum matching cardinality are characterized. These two parameters are used to develop bounds on the vertex cover and total vertex cover numbers of graphs and a resulting chain of vertex covering ...
Dutton Ronald, Klostermeyer William F.
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Dynamic monopolies in simple graphs [PDF]
AUT Journal of Mathematics and ComputingThis paper studies a repetitive polling game played on an $n$-vertex graph $G$. At first, each vertex is colored, Black or White. At each round, each vertex (simultaneously) recolors itself by the color of the majority of its closed neighborhood.
Leila Musavizadeh Jazaeri +1 more
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Cubicity, boxicity, and vertex cover
Discrete Mathematics, 2009 A $k$-dimensional box is the cartesian product $R_1 \times R_2 \times ... \times R_k$ where each $R_i$ is a closed interval on the real line. The {\it boxicity} of a graph $G$, denoted as $box(G)$, is the minimum integer $k$ such that $G$ is the intersection graph of a collection of $k$-dimensional boxes.
L. Sunil Chandran +2 more
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Identifying Vertex Covers in Graphs
The Electronic Journal of Combinatorics, 2012 An identifying vertex cover in a graph $G$ is a subset $T$ of vertices in $G$ that has a nonempty intersection with every edge of $G$ such that $T$ distinguishes the edges, that is, $e \cap T \ne \emptyset$ for every edge $e$ in $G$ and $e \cap T \ne f \cap T$ for every two distinct edges $e$ and $f$ in $G$.
Michael A. Henning, Anders Yeo
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Recognizing When Heuristics Can Approximate Minimum Vertex Covers Is Complete for Parallel Access to NP [PDF]
, 2005 For both the edge deletion heuristic and the maximum-degree greedy heuristic, we study the problem of recognizing those graphs for which that heuristic can approximate the size of a minimum vertex cover within a constant factor of r, where r is a fixed ...
Hemaspaandra, Edith +2 more
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Stability for Vertex Cycle Covers
The Electronic Journal of Combinatorics, 2017 In 1996 Kouider and Lonc proved the following natural generalization of Dirac's Theorem: for any integer $k\geq 2$, if $G$ is an $n$-vertex graph with minimum degree at least $n/k$, then there are $k-1$ cycles in $G$ that together cover all the vertices.This is tight in the sense that there are $n$-vertex graphs that have minimum degree $n/k-1$ and ...
József Balogh +2 more
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The distinguishing number and the distinguishing index of line and graphoidal graph(s)
AKCE International Journal of Graphs and Combinatorics, 2020 The distinguishing number (index) () of a graph is the least integer such that has a vertex labeling (edge labeling) with labels that is preserved only by a trivial automorphism.
Saeid Alikhani, Samaneh Soltani
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Kernelization and Parameterized Algorithms for 3-Path Vertex Cover
, 2016 A 3-path vertex cover in a graph is a vertex subset $C$ such that every path of three vertices contains at least one vertex from $C$. The parameterized 3-path vertex cover problem asks whether a graph has a 3-path vertex cover of size at most $k$.
B Brešar +24 more
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