Authors: Niaz Wassan, Said Salhi and Arif Imran
In this paper the multi-depot vehicle routing problem with heterogeneous fleet is investigated. A variable neighborhood search that incorporates additional features in addition to the adaptation of several neighborhoods and local search operators is proposed to solve this neglected but practical logistical problem.
These features include a preprocessing scheme for identifying borderline customers, a mechanism that aggregates and disaggregates routes between depots, and a neighborhood reduction test that saves a large amount of the CPU time, especially on the large instances. The proposed algorithm is highly competitive as it produces several new best results when tested on a set of data instances published in the literature.
Keywords: multi-depot vehicle routing, fleet size and mix vehicle routing, variable neighborhood search, logistics.