The Vehicle Routing Problem with Time Windows (VRPTW) is a combinatorial optimization problem that exists in various distribution systems. The problem deals with allocation of vehicles to service several customers, each customer has different available time, and the vehicles must visit the customers in their available time.This paper addresses the VRPTW by using an improved simulated annealing ...

In this research, the objective is to solve the problem of routing repair technicians to service equipment distributed in client locations. Provided a list of requests for service, we can assign any one of K technicians to service them. Each request for service includes a deadline to begin the service Wi, and an estimated service time si, decided from the diagnosis of the problem at the time of...

Recently, the quality and the diversity of transport services are more and more required. Moreover, in case of a great deal of services and selling goods, a significant part of price is transport cost. Thus, the design of models and applications which make possible efficient transport planning and scheduling becomes important. A great deal of real transport problems may be modelled by using Pic...

In emergency planning, consideration of emergency priorities is a necessity. This paper presents new formulations of the facility location problem (FLP) and vehicle routing problem with time windows (VRPTW) with considerations of priority. Our models ensure that higher priority locations are considered before the lower priority ones, for both facility and routing decisions. The FLP is solved us...

This report presents a survey of research on the Vehicle Routing Problem with Time Windows (VRPTW). The VRPTW can be described as the problem of designing least cost routes from one depot to a set of geographically scattered points. The routes must be designed in such a way that each point is visited only once by exactly one vehicle within a given time interval, all routes start and end at the ...

This paper documents our investigation into various heuristic methods to solve the vehicle routing problem with time windows (VRPTW) to near optimal solutions. The objective of the VRPTW is to serve a number of customers within prede®ned time windows at minimum cost (in terms of distance travelled), without violating the capacity and total trip time constraints for each vehicle. Combinatorial o...

Most of the studies on vehicle routing problem with time windows (VRPTW) aim to minimize total travel distance or travel time. This paper presents the VRPTW with a new objective function of minimizing the total fuel consumption. A mathematical model is proposed to formulate this problem. Then, a novel tabu search algorithm with a random variable neighborhood descent procedure (RVND) is given, w...

this paper discusses the multi-depot vehicle routing problem of heterogeneous fleet of vehicles with time windows for perishable commodities. the objective of the problem is to minimize the total time required for servicing all customers that is equivalent to the total cost. commodities are delivered to the customers with defined time windows by a fleet of heterogeneous vehicles, which have lim...

In emergency planning, consideration of emergency priorities is a necessity. This paper presents new formulations of the facility location problem (FLP) and vehicle routing problem with time windows (VRPTW) with considerations of priority. Our models ensure that higher priority locations are considered before the lower priority ones, for both facility and routing decisions. The FLP is solved us...