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An inequality chain of domination parameters for trees

E.J. Cockayne, O. Favaron, J. Puech, C.M. Mynhardt (1998)

Discussiones Mathematicae Graph Theory

We prove that the smallest cardinality of a maximal packing in any tree is at most the cardinality of an R-annihilated set. As a corollary to this result we point out that a set of parameters of trees involving packing, perfect neighbourhood, R-annihilated, irredundant and dominating sets is totally ordered. The class of trees for which all these parameters are equal is described and we give an example of a tree in which most of them are distinct.

Approximation algorithms for the design of SDH/SONET networks

Nadia Brauner, Yves Crama, Gerd Finke, Pierre Lemaire, Christelle Wynants (2003)

RAIRO - Operations Research - Recherche Opérationnelle

In this paper, a graph partitioning problem that arises in the design of SONET/SDH networks is defined and formalized. Approximation algorithms with performance guarantees are presented. To solve this problem efficiently in practice, fast greedy algorithms and a tabu-search method are proposed and analyzed by means of an experimental study.

Approximation algorithms for the design of SDH/SONET networks

Nadia Brauner, Yves Crama, Gerd Finke, Pierre Lemaire, Christelle Wynants (2010)

RAIRO - Operations Research

In this paper, a graph partitioning problem that arises in the design of SONET/SDH networks is defined and formalized. Approximation algorithms with performance guarantees are presented. To solve this problem efficiently in practice, fast greedy algorithms and a tabu-search method are proposed and analyzed by means of an experimental study.

Arbitrarily vertex decomposable caterpillars with four or five leaves

Sylwia Cichacz, Agnieszka Görlich, Antoni Marczyk, Jakub Przybyło, Mariusz Woźniak (2006)

Discussiones Mathematicae Graph Theory

A graph G of order n is called arbitrarily vertex decomposable if for each sequence (a₁,...,aₖ) of positive integers such that a₁+...+aₖ = n there exists a partition (V₁,...,Vₖ) of the vertex set of G such that for each i ∈ 1,...,k, V i induces a connected subgraph of G on a i vertices. D. Barth and H. Fournier showed that if a tree T is arbitrarily vertex decomposable, then T has maximum degree at most 4. In this paper we give a complete characterization of arbitrarily vertex decomposable caterpillars...

Balanced path decomposition of λ K n , n and λ K n , n *

Hung-Chih Lee, Chiang Lin (2009)

Czechoslovak Mathematical Journal

Let P k denote a path with k edges and ł K n , n denote the ł -fold complete bipartite graph with both parts of size n . In this paper, we obtain the necessary and sufficient conditions for ł K n , n to have a balanced P k -decomposition. We also obtain the directed version of this result.

𝓟-bipartitions of minor hereditary properties

Piotr Borowiecki, Jaroslav Ivančo (1997)

Discussiones Mathematicae Graph Theory

We prove that for any two minor hereditary properties 𝓟₁ and 𝓟₂, such that 𝓟₂ covers 𝓟₁, and for any graph G ∈ 𝓟₂ there is a 𝓟₁-bipartition of G. Some remarks on minimal reducible bounds are also included.

Bootstrap clustering for graph partitioning

Philippe Gambette, Alain Guénoche (2011)

RAIRO - Operations Research - Recherche Opérationnelle

Given a simple undirected weighted or unweighted graph, we try to cluster the vertex set into communities and also to quantify the robustness of these clusters. For that task, we propose a new method, called bootstrap clustering which consists in (i) defining a new clustering algorithm for graphs, (ii) building a set of graphs similar to the initial one, (iii) applying the clustering method to each of them, making a profile (set) of partitions, (iv) computing a consensus partition for this profile,...

Bootstrap clustering for graph partitioning∗

Philippe Gambette, Alain Guénoche (2012)

RAIRO - Operations Research

Given a simple undirected weighted or unweighted graph, we try to cluster the vertex set into communities and also to quantify the robustness of these clusters. For that task, we propose a new method, called bootstrap clustering which consists in (i) defining a new clustering algorithm for graphs, (ii) building a set of graphs similar to the initial one, (iii) applying the clustering method to each of them, making a profile (set) of partitions, (iv) computing a consensus partition for this profile,...

Currently displaying 61 – 80 of 454