01:30 PM - 01:55 PM
Multi-Objective VRP with Distance Based Decision Support
We look at the multiobjective vehicle routing problem
with route balancing (VRPRB). In a decision support
setting, we show the benefits of applying a structural
measure on the distances between solutions on (and near)
the pareto front. We also discuss ways to interpret and
implement various policies.
01:55 PM - 02:20 PM
Multi-Objective Multi-Attribute Vehicle Routing Problems
Multi-attribute routing problems are very interesting both because of their academic appeal and their real-life applications. Similarly, the multi-objective optimization problem is attracting more attention, because it provides new opportunities for defining more realistic problems. We address challenges related to multi-objective optimization in multi-attribute routing problems.
02:20 PM - 02:45 PM
A Matheuristic Approach for the Multi-Commodity One-to-One Pickup-and-Delivery Traveling Salesman Problem
This presentation addresses an extension of the TSP where a vehicle with a limited capacity must transport certain commodities from their origins to their destinations. Each commodity has a weight, and the objective is to find a minimum length Hamiltonian tour satisfying all the transportation requests without ever violating the capacity constraint. We propose for this problem a heuristic approach that combines mathematical programming and metaheuristic techniques. The method is able to improve the best known solutions for a set of instances from the literature in a reasonable amount of computation time.
02:45 PM - 03:10 PM
A Multicriteria Tabu Search Heuristic for the Dial-a-Ride Problem: Results for Real-Life Instances
Service quality criteria were identified during a survey with users of a Canadian dial-a-ride operator. These criteria were embedded in the multi-objective function of a tabu search algorithm designed to tackle real-life dial-a-ride problems. Computational results on real data will be presented. These results improve the understanding of tradeoffs between quality and cost for the service provider.