In this paper we consider the Asymmetric Quadratic Traveling Salesman Problem. Given a directed graph and a function that maps every pair of consecutive arcs to a cost, the problem consists in finding a cycle that visits every vertex exactly once and such that the sum of the costs is minimum. We propose an extended … Read more
This paper deals with the Traveling Salesman Problem (TSP) with Draft Limits (TSPDL), which is a variant of the well-known TSP in the context of maritime transportation. In this recently proposed problem, draft limits are imposed due to restrictions on the port infrastructures. Exact algorithms based on three mathematical formulations are proposed and their performance … Read more
Several ‘tubechallenges’ have been attempted on the London Underground network, often gaining vast press coverage. The most famous of them consists of trying to travel to all 275 stations of the London Underground network (known as ‘the tube’) in the shortest possible time. In this article we examine how Operational Research can assist potential record-breakers, … Read more