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 and Polytechnique Montreal

  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.