Demand Change In Vehicle Routing Problem With Backhauls

Vehicle routing problem with backhaul and time window(VRPBTW) is a variant of vehicle routing problem with time window. In reality, VRPBTW is applied in a wide range of logistics and distribution, like retail, express & freight and reverse logistics, and it is one of the cutting-edge issues in the field of logistics. In addition, all kinds of disruptions occur in the actual logistic activities. These disruptions disturb the original optimal routing solution, impact on serving customers on time and make service quality and service efficiency decline. Therefore, it is very necessary and meaningful to quickly and efficiently handle disruptions which emerge during vehicle routing problem with backhaul.Based on disruption management thought, this paper mainly researches VRPBTW with demand change. And its objective is to minimize the impact on the whole system by disruptions. The main researches in this paper are as follows:(1) After static VRPBTW and its model are defined, demand changes of VRPBTW in real logistics are analyzed. And then the impact on the original optimal solution is identified, analyzed and measured. At last, a disruption recovery model is constructed.(2) At first a mixed tabu search algorithm for static VRPBTW is put forward. And then according to features of VRPBTW with demand change, a strategy-based heuristic algorithm is designed for the disruption recovery model.(3) An experiment platform based on the benchmark is designed. The mixed tabu search algorithm for the static VRPBTW and the strategy-based heuristic algorithm for disruption problem are tested on this platform. The results show that the model and algorithms are effective.The disruption recovery model for VRPBTW with demand change effectively reduces the disturbance on the original optimal routing solution. And to a large extent, it also reduces customers' service time delay and the loss of logistic service providers' cost. Moreover, the research provides references for logistic enterprises and lays the foundation for other disruptions in VRPBTW in future.