Covering vehicle routing problem: applications for refugee related services

Abstract

The world is facing a refugee crisis because of the ongoing war in Syria, and it is important to develop refugees' life conditions and increase their integration to the host communities. There are several services given to refugees to improve humanitarian development. The distribution of cash and e-vouchers to refugees and the routing of trucks which provide Child Friendly Spaces to vulnerable refugee children are addressed in this study. Both problems have similar characteristics as they provide services using mobile vehicles. The distribution of e-vouchers problem is applied for two scenarios, where local distribution centers are opened to cover an area, and a combination of local distribution centers and hand-tohand delivery is conducted to increase the accessibility. The given problems are categorized as Covering Vehicle Routing Problem and Covering Vehicle Routing Problem with Integrated Tours which are introduced to the literature. The performance of the proposed models is tested and a sensitivity analysis on the problem parameters is given. Three optimization based heuristics are proposed to improve solving times. The proposed solutions are applied to a real life case of city Kilis. In order to apply the models to the routing of Mobile Child Friendly Spaces problem, a bi-objective version of the proposed models is given where the aim is to minimize the unsatis ed demand while minimizing travelled distance. -constraint method is applied to solve the bi-objective application and all Pareto Optimal solutions are obtained.