A bi-objective green location-routing model and solving problem using a hybrid metaheuristic algorithm

Abstract

In the field of operations research, vehicle routing problems (VRP) have a great deal of importance because of its applications in transportation of goods and services. Until now many studies have been done about VRP, but there are few studies which have considered environmental perspective towards the problem. Besides, most of the bygone studies usually have considered only one objective which is minimisation of total travelling cost. In this paper, we try to tackle some flaws of the previous works in the proposed models for green routing problems by considering multiple depots, constraints of hard and soft time windows, heterogeneous vehicles, multiple periods and products. Since the aforementioned problem is considered to be NP-hard, metaheuristic algorithms are needed for solving it. Therefore, to tackle NP-hardness of the proposed model a combined algorithm of genetics algorithms (GA) and simulated annealing (SA) algorithms is proposed. Finally, for demonstrating the efficiency of the proposed algorithm, the solutions provided by the algorithm is compared to the solutions obtained from exact solving method in Gams software. The results demonstrate the efficiency of the proposed method.