Letchford, Adam and Nasiri, Saeideh D. and Oukil, Amar (2014) Pricing routines for vehicle routing with time windows on road networks. Computers and Operations Research, 51. pp. 331-337. ISSN 0305-0548
Abstract
Several very effective exact algorithms have been developed for vehicle routing problems with time windows. Unfortunately, most of these algorithms cannot be applied to instances that are defined on road networks, because they implicitly assume that the cheapest path between two customers is equal to the quickest path. Garaix and coauthors proposed to tackle this issue by first storing alternative paths in an auxiliary multi-graph, and then using that multi-graph within a branch-and-price algorithm. We show that, if one works with the original road network rather than the multi-graph, then one can solve the pricing subproblem more quickly, in both theory and practice.