A STUDY ON COLLABORATIVE PICK-UP AND DELIVERY ROUTING PROBLEM OF LINE-HAUL VEHICLES IN EXPRESS DELIVERY SERVICES

In the Korean express delivery service market, many companies have been striving to extend their own market share. An express delivery system is defined as a network of customers, service centers and consolidation terminals. Some companies operate line-haul vehicles in milk-run types of pick-up and delivery services among consolidation terminals and service centers with locational disadvantages. The service centers with low sales are kept operating, even if they are unprofitable, to ensure the quality of service. Recently, a collaborative operation is emerging as an alternative to reduce the operating costs of the handicaped centers. This study considers a collaborative service network with pick-up and delivery visits for line-haul vehicles for the purpose of maximizing the incremental profits of collaborating companies. The main idea is to operate only one service center shared by different companies for service centers with low demands and change the visit schedules accordingly. A genetic algorithm-based heuristic is proposed and assessed through a numerical example