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Minimal 2-dominating sets in trees

Marcin Krzywkowski (2013)

RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications

We provide an algorithm for listing all minimal 2-dominating sets of a tree of order n in time 𝒪(1.3248n). This implies that every tree has at most 1.3248n minimal 2-dominating sets. We also show that this bound is tight.

Minimum convex-cost tension problems on series-parallel graphs

Bruno Bachelet, Philippe Mahey (2003)

RAIRO - Operations Research - Recherche Opérationnelle

We present briefly some results we obtained with known methods to solve minimum cost tension problems, comparing their performance on non-specific graphs and on series-parallel graphs. These graphs are shown to be of interest to approximate many tension problems, like synchronization in hypermedia documents. We propose a new aggregation method to solve the minimum convex piecewise linear cost tension problem on series-parallel graphs in O ( m 3 ) operations.

Minimum convex-cost tension problems on series-parallel graphs

Bruno Bachelet, Philippe Mahey (2010)

RAIRO - Operations Research

We present briefly some results we obtained with known methods to solve minimum cost tension problems, comparing their performance on non-specific graphs and on series-parallel graphs. These graphs are shown to be of interest to approximate many tension problems, like synchronization in hypermedia documents. We propose a new aggregation method to solve the minimum convex piecewise linear cost tension problem on series-parallel graphs in O(m3) operations.

Motion planning in cartesian product graphs

Biswajit Deb, Kalpesh Kapoor (2014)

Discussiones Mathematicae Graph Theory

Let G be an undirected graph with n vertices. Assume that a robot is placed on a vertex and n − 2 obstacles are placed on the other vertices. A vertex on which neither a robot nor an obstacle is placed is said to have a hole. Consider a single player game in which a robot or obstacle can be moved to adjacent vertex if it has a hole. The objective is to take the robot to a fixed destination vertex using minimum number of moves. In general, it is not necessary that the robot will take a shortest path...

New lower bounds on the weighted chromatic number of a graph

Massimiliano Caramia, Jirí Fiala (2004)

Discussiones Mathematicae Graph Theory

In this paper we present theoretical and algorithmic results for the computation of lower bounds on the chromatic number of a weighted graph. In particular, we study different ways of a possible improvement of the lower bound offered by a maximum weighted clique. Based on our findings we devise new algorithms and show their performance on random graphs.

Odd and residue domination numbers of a graph

Yair Caro, William F. Klostermeyer, John L. Goldwasser (2001)

Discussiones Mathematicae Graph Theory

Let G = (V,E) be a simple, undirected graph. A set of vertices D is called an odd dominating set if |N[v] ∩ D| ≡ 1 (mod 2) for every vertex v ∈ V(G). The minimum cardinality of an odd dominating set is called the odd domination number of G, denoted by γ₁(G). In this paper, several algorithmic and structural results are presented on this parameter for grids, complements of powers of cycles, and other graph classes as well as for more general forms of "residue" domination.

On co-bicliques

Denis Cornaz (2007)

RAIRO - Operations Research

A co-biclique of a simple undirected graph G = (V,E) is the edge-set of two disjoint complete subgraphs of G. (A co-biclique is the complement of a biclique.) A subset F ⊆ E is an independent of G if there is a co-biclique B such that F ⊆ B, otherwise F is a dependent of G. This paper describes the minimal dependents of G. (A minimal dependent is a dependent C such that any proper subset of C is an independent.) It is showed that a minimum-cost dependent set of G can be determined in polynomial...

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