Fuzzy green vehicle routing problem with simultaneous pickup – delivery and time windows

In this paper, we propose a fuzzy green vehicle routing problem with simultaneous pickup and delivery and time windows (F-GVRP-SPDTW), in which the amounts of fuel consumption and emission are estimated by a comprehensive modal emission model. A mixed integer nonlinear programming model is proposed to minimize the cost of fuel consumption and emissions of vehicles. Moreover, the fuzzy approach with credibility measure is applied under conditions in which both pickup and delivery demands are uncertain. To solve the problem, we have proposed an adaptive large neighborhood search heuristic by applying new removal and insertion operators. Finally, computational experiments are conducted on a set of benchmark instances from the literature to evaluate the efficiency of the proposed solution technique. The results indicate that the proposed solution method is capable of finding high quality solutions in most of the instances