4 Presentations

• 
  10:30 AM - 10:55 AM

  A comparison of formulations for the three-level lot sizing and transportation problem

  • Matthieu Gruson, presenter, HEC Montréal/CIRRELT
  • Jean-François Cordeau, HEC Montréal, GERAD, CIRRELT
  • Raf Jans, HEC Montréal

  In this talk we will present several MIP formulations to solve the three-level lot sizing and transportation problem. The formulations are either adapted from the two-level lot sizing literature or new. The results of extensive computational experiments will be given to compare the performance of each formulation.

• 
  10:55 AM - 11:20 AM

  A Branch-and-cut algorithm for the routing and refueling station location problem

  • Okan Arslan, presenter, GERAD, HEC Montréal
  • Oya Karasan, Bilkent University
  • A.Ridha Mahjoub, Université Paris Dauphine
  • Hande Yaman, Bilkent University

  We introduce a novel model for the routing and refueling station location problem for alternative fuel vehicles and develop a branch-and-cut algorithm as an exact solution methodology. Computational experiments show that the algorithm improves solution times by orders of magnitude with respect to previously developed models and methods.

• 
  11:20 AM - 11:45 AM

  Exact methods for the Time Window Assignment Vehicle Routing Problem

  • Kevin Dalmeijer, presenter, Erasmus University Rotterdam
  • Guy Desaulniers, GERAD - Polytechnique Montréal

  We consider the Time Window Assignment Vehicle Routing Problem (TWAVRP), the problem of assigning time windows for delivery before demand volume becomes known. We consider both branch-and-cut and branch-price-and-cut algorithms to solve this problem to optimality. The algorithms are compared on their performance on a set of test-instances.

• 
  11:45 AM - 12:10 PM

  Exact and Heuristic Algorithms for an Industrial and Tramp Ship Routing and Scheduling Problem

  • Gabriel Homsi, Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio)
  • Rafael Martinelli, presenter, Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio)
  • Thibaut Vidal, Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio)

  We tackle a ship routing problem which extends the Pickup and Delivery Problem with Time Windows with heterogeneous fleet, compatibility constraints and different ship starting points. We propose a Hybrid Genetic Search with Advanced Diversity Control and a column generation algorithm. Our experiments show the good performance of the methods.