Séminaire (organisé par l’équipe de recherche RO)

Agostinho AGRA

Professeur à l’université de Aveiro, Portugal

The robust vehicle routing problem with time windows

Jeudi 25 avril à 11h en C221

Résumé :

This work addresses the robust vehicle routing problem with time windows. We are motivated by a problem that arises in maritime transportation where delays are frequent and should be taken into account. Our model only allows routes that are feasible for all values of the travel times in a predetermined uncertainty polytope, which yields a robust optimization problem. We propose two new formulations for the robust problem, each based on a different robust approach.

The first formulation extends the well-known resource inequalities formulation by employing robust programming with recourse. We propose two techniques, which, using the structure of the problem, allow to reduce significantly the number of extreme points of the uncertainty polytope.

The second formulation generalizes a path inequalities formulation to the uncertain context. The uncertainty appears implicitly in this formulation, so that we develop a new cutting plane technique for robust combinatorial optimization problems with complicated constraints. In particular, efficient separation procedures are discussed. We compare the two formulations on maritime transportation instances.


FR SHIC 3272

Collegium UTC/CNRS