This paper presents a variant of the basic vehicle routing problem (VRP) called the multi-trip vehicle routing problem with backhauls and time windows (MTVRPBTW). Two objectives are considered: minimizing the number of vehicles and minimizing the total tour duration time. These two objectives are handled into a single objective by defining a wighted sum. A mixed integer linear programming (MILP) model is formulated to represent the MTVRPBTW. Variable neighborhood descent (VND) is proposed to solve the MTVRPBTW. In this paper, two schemes of VND is proposed depending on the order of neighborhood structures applied.

@inproceedings{oscm-2019-518,
  title={MULTI-TRIP VEHICLE ROUTING PROBLEM WITH BACKHAULS AND TIME WINDOWS},
  year={2019},
  author={Suprayogi Suprayogi and Rully Tri Cahyono and Alek Topani Lubis},
  booktitle={Proceedings of the 9th International Conference on Operations and Supply Chain Management, Vietnam, 2019},
  doi={10.31387/oscm410219}
}

Suprayogi Suprayogi, Rully Tri Cahyono, Alek Topani Lubis (2019). MULTI-TRIP VEHICLE ROUTING PROBLEM WITH BACKHAULS AND TIME WINDOWS. In Proceedings of the 9th International Conference on Operations and Supply Chain Management, Vietnam, 2019. https://doi.org/10.31387/oscm410219