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Redinv-SA: la simulated annealing for the quadratic assignment problem

N. M.M. de Abreu, T. M. Querido, P. O. Boaventura-Netto (2010)

RAIRO - Operations Research

An algebraic and combinatorial approach to the study of the Quadratic Assignment Problem produced theoretical results that can be applied to (meta) heuristics to give them information about the problem structure, allowing the construction of algorithms. In this paper those results were applied to inform a Simulated Annealing-type heuristic (which we called RedInv-SA). Some results from tests with known literature instances are presented.

Resource allocation in a mobile telephone network : a constructive repair algorithm

Patrice Boizumault, Philippe David, Housni Djellab (2001)

RAIRO - Operations Research - Recherche Opérationnelle

To cope with its development, a French operator of mobile telephone network must periodically plan the purchase and the installation of new hardware, in such a way that a hierarchy of constraints (required and preferred) is satisfied. This paper presents the “constructive repair” method we used to solve this problem within the allowed computing time (1 min). This method repairs the planning during its construction. A sequence of repair procedures is defined: if a given repair cannot be achieved...

Resource allocation in a mobile telephone network: A constructive repair algorithm

Patrice Boizumault, Philippe David, Housni Djellab (2010)

RAIRO - Operations Research

To cope with its development, a French operator of mobile telephone network must periodically plan the purchase and the installation of new hardware, in such a way that a hierarchy of constraints (required and preferred) is satisfied. This paper presents the “constructive repair” method we used to solve this problem within the allowed computing time (1 min). This method repairs the planning during its construction. A sequence of repair procedures is defined: if a given repair cannot be achieved...

Semi-definite positive programming relaxations for graph K 𝐧 -coloring in frequency assignment

Philippe Meurdesoif, Benoît Rottembourg (2001)

RAIRO - Operations Research - Recherche Opérationnelle

In this paper we will describe a new class of coloring problems, arising from military frequency assignment, where we want to minimize the number of distinct n -uples of colors used to color a given set of n -complete-subgraphs of a graph. We will propose two relaxations based on Semi-Definite Programming models for graph and hypergraph coloring, to approximate those (generally) NP-hard problems, as well as a generalization of the works of Karger et al. for hypergraph coloring, to find good feasible...

Semi-Definite positive Programming Relaxations for Graph Kn-Coloring in Frequency Assignment

Philippe Meurdesoif, Benoît Rottembourg (2010)

RAIRO - Operations Research

In this paper we will describe a new class of coloring problems, arising from military frequency assignment, where we want to minimize the number of distinct n-uples of colors used to color a given set of n-complete-subgraphs of a graph. We will propose two relaxations based on Semi-Definite Programming models for graph and hypergraph coloring, to approximate those (generally) NP-hard problems, as well as a generalization of the works of Karger et al. for hypergraph coloring, to find good feasible...

Separable convexification and DCA techniques for capacity and flow assignment problems

P. Mahey, Thai Q. Phong, H. P. L. Luna (2001)

RAIRO - Operations Research - Recherche Opérationnelle

We study a continuous version of the capacity and flow assignment problem (CFA) where the design cost is combined with an average delay measure to yield a non convex objective function coupled with multicommodity flow constraints. A separable convexification of each arc cost function is proposed to obtain approximate feasible solutions within easily computable gaps from optimality. On the other hand, DC (difference of convex functions) programming can be used to compute accurate upper bounds and...

Separable convexification and DCA techniques for capacity and flow assignment problems

P. Mahey, Thai Q. Phong, H. P.L. Luna (2010)

RAIRO - Operations Research

We study a continuous version of the capacity and flow assignment problem (CFA) where the design cost is combined with an average delay measure to yield a non convex objective function coupled with multicommodity flow constraints. A separable convexification of each arc cost function is proposed to obtain approximate feasible solutions within easily computable gaps from optimality. On the other hand, DC (difference of convex functions) programming can be used to compute accurate upper bounds and...

Solving the simple plant location problem by genetic algorithm

Jozef Kratica, Dušan Tošic, Vladimir Filipović, Ivana Ljubić (2001)

RAIRO - Operations Research - Recherche Opérationnelle

The simple plant location problem (SPLP) is considered and a genetic algorithm is proposed to solve this problem. By using the developed algorithm it is possible to solve SPLP with more than 1000 facility sites and customers. Computational results are presented and compared to dual based algorithms.

Solving the simple plant location problem by genetic algorithm

Jozef Kratica, Dušan Tošic, Vladimir Filipović, Ivana Ljubić (2010)

RAIRO - Operations Research

The simple plant location problem (SPLP) is considered and a genetic algorithm is proposed to solve this problem. By using the developed algorithm it is possible to solve SPLP with more than 1000 facility sites and customers. Computational results are presented and compared to dual based algorithms.

The Capacitated Arc Routing Problem. A heuristic algorithm.

Enrique. Benavent, V. Campos, Angel Corberán, Enrique Mota (1990)

Qüestiió

In this paper we consider the Capacitated Arc Routing Problem, in which a fleet of K vehicles, all of them based on a specific vertex (the depot) and with a known capacity Q, must service a subset of the edges of the graph, with minimum total cost and such that the load assigned to each vehicle does not exceed its capacity.A heuristic algorithm for this problem is proposed consisting of: the selection of K centers, the construction of K connected graphs with associated loads not exceeding the vehicle...

The Variance Location Problem on a Network with Continuously distributed demand

Ma Cruz López de los Mozos, Juan A. Mesa (2010)

RAIRO - Operations Research

Most location problems on networks consider discrete nodal demand. However, for many problems, demands are better represented by continuous functions along the edges, in addition to nodal demands. Several papers consider the optimal location problem of one or more facilities when demands are continuously distributed along the network, and the objective function dealt with is the median one. Nevertheless, in location of public services it is desirable to use an equity criterion. One of the latter...

Three tabu search methods for the MI-FAP applied to 802.11 networks

Sacha Varone, Nicolas Zufferey (2008)

RAIRO - Operations Research - Recherche Opérationnelle

Wireless LAN using IEEE 802.11 networks are now widely deployed at home by residential users or in hot spots by telecommunication operators. A hot spot is a place where a set of access points (APs) are located nearby each other and can serve many users. Since perturbations can degrade the quality of the signal, a careful channel assignment to each AP has to be done. Channel assignment of APs at hot spots, and more generally setup configuration and management, is still often done manually. In this...

Three tabu search methods for the MI-FAP applied to 802.11 networks

Sacha Varone, Nicolas Zufferey (2009)

RAIRO - Operations Research

Wireless LAN using IEEE 802.11 networks are now widely deployed at home by residential users or in hot spots by telecommunication operators. A hot spot is a place where a set of access points (APs) are located nearby each other and can serve many users. Since perturbations can degrade the quality of the signal, a careful channel assignment to each AP has to be done. Channel assignment of APs at hot spots, and more generally setup configuration and management, is still often done manually. In this...

Currently displaying 61 – 80 of 82