|
|
|
Séance MA4 - Conception de réseaux I / Network Design I
Jour |
lundi, le 09 mai 2005 |
Salle |
Gérard-Parizeau |
Président |
Bernard Gendron |
Présentations
10h30 |
Cutset Based Cutting-Plane Algorithm for Multicommodity Capacitated Fixed Charge Network Design |
|
Mervat Chouman, Université de Montréal, CRT et Informatique et recherche opérationnelle, C.P. 6128, Succ. Centre-ville, Montréal, Québec, H3C 3J7
Teodor Gabriel Crainic, Université du Québec à Montréal, CRT, C.P. 6128, Succ. Centre-ville, Montréal, Québec, Canada, H3C 3J7
Bernard Gendron, Université de Montréal, CRT et Informatique et recherche opérationnelle, C.P. 6128, Succ. Centre-ville, Test, Montréal, Québec, Canada, H3C 3J7
Edith Naudin, UQUAM, Centre de Recherche sur les Transports, Universite de Montreal, C.P. 6128, succursale Centre-ville, Montreal, Quebec, Canada, H3C 3J7
We present a cutting-plane algorithm to improve the lower bounds for the multicommodity capacitated fixed charge network design problem. Specifically, the cutting-plane method incorporates generalizations of well-known valid inequalities, as well as new families, all based on cutsets of the network. We present experimental results showing the effectiveness of the cutting-plane procedure and the impact of individual cut families in terms of computational time and lower bound improvement.
|
10h55 |
A Combined Dual Ascent/Variable Neighbourhood Heuristic for a Multi-Echelon Location-Distribution Problem |
|
Bernard Gendron, Université de Montréal, CRT et Informatique et recherche opérationnelle, C.P. 6128, Succ. Centre-ville, Test, Montréal, Québec, Canada, H3C 3J7
Frédéric Semet, Université de Valenciennes, LAMIH-ROI, Le Mont Houy, 59313 Valenciennes, Cedex 9, France
Imen Temimi, Université de Montréal, CRT, C.P. 6128, succ. Centre-ville, Montréal, Québec, Canada, H3C 3J7
We consider a multi-echelon location-distribution problem arising from an actual application in fast delivery service. We propose a heuristic that exploits a simple plant location relaxation of a MIP formulation of the problem to solve a large-scale actual application. The heuristic combines DUALOC with a variable neighborhood descent.
|
11h20 |
A Lifting Procedure for Cutset Inequalities |
|
Alysson M. Costa, HEC Montréal, CRT, GERAD et Chaire de recherche du Canada en distributique, 3000, ch. de la Côte-Sainte-Catherine, Montréal, Quebec, Canada, H3T 2A7
Jean-François Cordeau, HEC Montréal, CRT, GERAD et Chaire de recherche du Canada en distributique, 3000, ch. de la Côte-Sainte-Catherine, Montréal, Québec, Canada, H3T 2A7
Bernard Gendron, Université de Montréal, CRT et Informatique et recherche opérationnelle, C.P. 6128, Succ. Centre-ville, Test, Montréal, Québec, Canada, H3C 3J7
Cutset inequalities are an important family of valid inequalities for network design problems. This article presents a lifting procedure to strengthen cutset inequalities by solving shortest-path problems. It also shows that cutset inequalities are a special case of a more general class of inequalities, known as feasibility constraints, for which the lifting procedure is also valid. A Benders decomposition framework is used to show the efficiency of the procedure both for the general feasibility constraints and for the cutset inequalities.
|
|