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Solving the multi-commodity capacitated multi-facility Weber problem using Lagrangean relaxation and a subgradient-like algorithm / M. H. Akyüz in Journal of the operational research society (JORS), Vol. 63 N° 6 (Juin 2012) 

Public ISBD [article]  in Journal of the operational research society (JORS) > Vol. 63 N° 6 (Juin 2012) . - pp. 771–789 Titre : Solving the multi-commodity capacitated multi-facility Weber problem using Lagrangean relaxation and a subgradient-like algorithm Type de document : texte imprimé Auteurs : M. H. Akyüz, Auteur ; T. Öncan, Auteur ; Altinel, I. K., Auteur Année de publication : 2012 Article en page(s) : pp. 771–789 Note générale : Operational research Langues : Anglais (eng) Mots-clés : multi-commodity  facility  location  allocation  Lagrangean  relaxation  Discrete  approximation Index. décimale : 001.424 Résumé : The Multi-commodity Capacitated Multi-facility Weber Problem (MCMWP) is concerned with locating I-capacitated facilities in the plane in order to satisfy the demands of J customers for K commodities so that the total transportation cost is minimized. We propose a Lagrangean relaxation scheme and a subgradient-like algorithm based on the relaxation of the capacity and commodity bundle constraints. The resulting subproblem is a variant of the well-known Multi-facility Weber Problem and it can be solved by using column generation and branch-and-price on an equivalent set covering formulation, which is accurate but extremely inefficient. Therefore, we devise different strategies to increase the efficiency. They mainly benefit from the effective usage of the lower and upper bounds on the optimal value of the Lagrangean subproblem. On the basis of extensive computational tests, we can say that they increase the efficiency considerably and result in accurate Lagrangean heuristics. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n6/abs/jors201181a.html [article] Solving the multi-commodity capacitated multi-facility Weber problem using Lagrangean relaxation and a subgradient-like algorithm [texte imprimé] / M. H. Akyüz, Auteur ; T. Öncan, Auteur ; Altinel, I. K., Auteur . - 2012 . - pp. 771–789. Operational research Langues : Anglais (eng) in Journal of the operational research society (JORS) > Vol. 63 N° 6 (Juin 2012) . - pp. 771–789 Mots-clés : multi-commodity  facility  location  allocation  Lagrangean  relaxation  Discrete  approximation Index. décimale : 001.424 Résumé : The Multi-commodity Capacitated Multi-facility Weber Problem (MCMWP) is concerned with locating I-capacitated facilities in the plane in order to satisfy the demands of J customers for K commodities so that the total transportation cost is minimized. We propose a Lagrangean relaxation scheme and a subgradient-like algorithm based on the relaxation of the capacity and commodity bundle constraints. The resulting subproblem is a variant of the well-known Multi-facility Weber Problem and it can be solved by using column generation and branch-and-price on an equivalent set covering formulation, which is accurate but extremely inefficient. Therefore, we devise different strategies to increase the efficiency. They mainly benefit from the effective usage of the lower and upper bounds on the optimal value of the Lagrangean subproblem. On the basis of extensive computational tests, we can say that they increase the efficiency considerably and result in accurate Lagrangean heuristics. DEWEY : 001.424 ISSN : 0160-5682 En ligne : http://www.palgrave-journals.com/jors/journal/v63/n6/abs/jors201181a.html