La localisation d'un site d'approvisionnement pour minimiser les coûts d'opérations est une problématique industrielle courante. Les variables classiques co...

Several variants and generalizations of the Or-opt heuristic for the <i>Symmetric Traveling Salesman Problem</i> are developed and compared on random and pla...

The continuous location-allocation problem requires finding sites for <i>m</i> new facilities in the plane in order to serve <i>n</i> users such that the to...

Variable Neighborhood Search (VNS) is a recent and effective metaheuristic for solving combinatorial and global optimization problems. It is capable of esca...

This paper introduces the first exact approach for constructing aircrew member personalized monthly work schedules when a preferential bidding system (PBS) ...

The global <i>k</i>-means heuristic is a recently proposed (Likas et al. 2003) incremental approach for minimum sum-of-squares clustering of a set <i>X</i> ...

In this paper we develop a Variable neighborhood search (VNS) heuristic for solving Mixed-Integer Programs (MIP’s). It uses CPLEX, the general-purpose MIP s...

An upper bound is given on the variance of degrees of graphs with <i>n</i> vertices, <i>m</i> edges and maximum degree &Delta;. Particular cases of chemical...

The fractional aircraft market is the fastest growing segment of the business aircraft industry. A fractional aircraft operation is complex - essentially an...

The algebraic connectivity <i>a(G)</i> of a graph <i>G = (V,E)</i> is the second smallest eigenvalue of its Laplacian matrix. Using the AutoGraphiX (AGX) sys...

Ce document présente un modèle intégrateur de la logistique inverse. Le modèle est générique et peut servir à différents types d’entreprises. Le contexte du...

Column Generation (CG) algorithms are instrumental in many areas of applied optimization, where Linear Programs with an enormous number of columns need to ...

We describe an approach that computes an optimal primal basic solution given an optimal vector of dual multipliers. It consists in restricting the dual prob...

This article presents a formulation for the job shop problem based on the Dantzig- Wolfe decomposition with a subproblem for each machine. Each subproblem i...

In most vehicle routing and crew scheduling applications solved by column generation, the subproblem corresponds to a shortest path problem with resource con...

We give a didactic introduction to the use of the column generation technique in linear and in particular in integer programming. We touch on both, the relev...

This paper proposes a generalization of the proximal point algorithm using both penalty and trust region concepts. Finite convergence is established while as...

This article reviews some of the best metaheuristics proposed in recent years for the Vehicle Routing Problem. These are based on local search, on populatio...

The uniting feature of combinatorial optimization and extremal graph theory is that in both areas one should &#64257;nd extrema of a function defined in most...

The problem of determining a shortest loop incident to each cell of a block layout is considered. A compact formulation is developed for this problem and a ...