This paper presents a hybrid evolutionary algorithm (HEA) to solve heterogeneous fleet vehicle routing problems with time windows. There are two main types of such problems, namely the fleet size and mix vehicle routing problem with time windows (F) and the heterogeneous fixed fleet vehicle routing problem with time windows (H), where the latter, in contrast to the former, assumes a limited ava...

in this paper, we study the multi-depot vehiclerouting problem with inter-depot routes, in which the vehicles can replenish atintermediate depots. vehicles leave the origin depot with load on-board andserve customers until out of load. they may visit an intermediate depot toreplenish and finally return to the origin depot, completing their route. weinitiate a mathematical mixed integer programm...

In this paper, we consider two-tier City Logistics systems accounting for both the inbound and outbound traffic that have not been taken into account in models and algorithms for vehicle routing research. The problem under study, called the Multi-zone Multi-trip Pickup and Delivery Problem with Time Windows and Synchronization, has two sets of intertwined decisions: the routing decisions which ...

A variety of integer programming formulations have been proposed for Vehicle Routing Problems (VRPs), including the so-called twoand three-index formulations, the set partitioning formulation, and various formulations based on extra variables representing the flow of one or more commodities. Until now, there has not been a systematic study of how these formulations relate to each other. An exce...

The Capacitated Vehicle Routing Problem with Balanced Routes and Time Windows (CVRPBRTW) aims at optimizing the total distance cost, the number of vehicles used, and the route balancing subject to time windows and other constraints. Due to the multiple and often conflicting objectives, the proposed problem is formulated and tackled in a MultiObjective Optimization manner using a Hybrid Multi-Ob...