A branch-and-cut algorithm for the capacitated open vehicle routing problem

Abstract

In open vehicle routing problems, the vehicles are not required to return to the depot after completing service. In this paper, we present the first exact optimization

Disruption management in vehicle routing and scheduling for road freight transport: a review

“…Two Tabu Search heuristic algorithms are developed and tested over a set of test problems generated for the purpose. The computational results of the heuristics are then compared to an exact algorithm based on the method proposed by Letchford et al (2007) for the Open Vehicle Routing Problem.…”

Enhanced mixed integer programming techniques and routing problems

“…However, if the undirected case is considered, the open version turns out to be more general than the closed one. Indeed, as shown by Letchford et al [113], any closed VRP on n customers in a complete undirected graph can be transformed into an OVRP on n customers, but there is no transformation in the reverse direction. Further, there are many practical applications in which OVRP naturally arises.…”

Robust Branch-Cut-and-Price Algorithms for Vehicle Routing Problems

“…They include most of the classical E instances from Christofides and Eilon [10] and also some representative instances from sets A, B and P available at www.branchandcut.org. We compare our bounds with those obtained by the branch-and-cut by Letchford et al [29], Let. columns.…”

“…The Capacitated Open Vehicle Routing Problem (COVRP) [29] is a variant of the classical CVRP where the vehicle needs not to return to the depot once no more clients need to be visited (or, symmetrically, the vehicle needs not to start at the depot). This routing problem covers the case where vehicles are hired for each route job, having a cost model that charges only while the vehicle is loaded.…”

“…The results are presented in Tables 4 and 5, analogous to Tables 1 and 2, respectively. The upper bounds in column Prev UB in Table 4 are from [29] too. As instances E-n101-k8 and E-n101-k14 had never been solved before, we allowed a little more than 10,000 seconds for their runs.…”