Abstract The issue of carbon emission reduction has attracted extensive attention in academic circles, but there are few studies on the Pareto frontier analysis multi-depot green vehicle routing problem with multi-objective. In order to effectively balance economic and environmental effects, this paper constructs a bi-objective optimization model for open problems time windows, which takes oper...

In this paper, we introduce the Vehicle Routing Problem with Flexible Time Windows (VRPFlexTW), in which vehicles are allowed to deviate from customer time windows by a given tolerance. This flexibility enables savings in the operational costs of carriers, since customers may be served before and after the earliest and latest time window bounds, respectively. However, as time window deviations ...

mobile ad hoc networks (manets) are composed of mobile stations communicating through wireless links, without any fixed backbone support. in these networks, limited power energy supply, and frequent topology changes caused by node mobility, makes their routing a challenging problem. tora is one of the routing protocols that successfully copes with the nodes’ mobility side effects, but it doesn’...

This paper studies the ambulance routing problem (ARP) in disaster situations when a large number of injured people from various locations require receiving treatments and medical aids. In such circumstances, many people summoning the ambulances but the capacity and number of emergency vehicles are not sufficient to visit all the patients at the same time. Therefore, a pivotal issue is to manag...

An algorithm is described for solving the node-to-set disjoint paths problem in bi-rotator graphs, which are obtained by making each edge of a rotator graph bi-directional. The algorithm is of polynomial order of n for an n-bi-rotator graph. It is based on recursion and divided into three cases according to the distribution of destination nodes in the classes into which the nodes in a bi-rotato...

Vehicle routing problems have various extensions such as time windows, multiple vehicles, backhauls, simultaneous delivery and pick-up, etc. The objectives of all these problems are to design optimal routes minimizing total distance traveled, minimizing number of vehicles, etc that satisfy corresponding constraints. In this study, an ant colony optimization based heuristic that can be used to s...

This research addresses an empirical multi-depot vehicle routing case for a fixed-route trucking carrier. In this case, the characteristics of vehicle routing problems, including multi-depots, dispatching quantity, routes arrangement and time-window constraints, are considered in order to reduce the delivering cost. A hybrid heuristic algorithm is developed in order to solve this practical prob...

In this paper, we discuss the convergence of two time window discretization methods for the traveling salesman problem with time window constraints. These methods are general and can be applied to other vehicle routing and scheduling problems with time windows. The first method provides a feasible solution to the problem while the second provides a lower bound for the minimization problem. Anal...

Vehicle Routing Problem with Time Window (VRPTW), an extension of VRP, is a complex combinatorial problem having many real life applications. It can be described as the problem of minimizing the total route cost while satisfying the capacity and time window constraint. Ant Colony System (ACS) is a meta heuristic that is often applied to solve VRPTW. In this paper an attempt has been made to enh...