Practical vehicle routing problems generally have both routing and scheduling aspects to consider. However, few heuristicmethods exist that address both these complicated aspects simultaneously. We present heuristics to determine an efficient circular traversal of a weighted graph that requires a subset of its edges to be traversed, each a specified (potentially different) number of times. Cons...

one of the most important extensions of the capacitated vehicle routing problem (cvrp) is the vehicle routing problem with simultaneous pickup and delivery (vrpspd) where customers require simultaneous delivery and pick-up service. in this paper, we propose an effective ant colony optimization (eaco) which includes insert, swap and 2-opt moves for solving vrpspd that is different with common an...

Home health care problems consist in scheduling visits to home patients by professionals while following a series of requirements. This paper studies the Health Care Routing and Scheduling Problem, which comprises multi-attribute vehicle routing problem with soft time windows. Additional route inter-dependency constraints apply for requesting multiple visits, either simultaneous or precedence. ...

using greedy clustering method to solve capacitated location-routing problem with fuzzy demands abstract in this paper, the capacitated location routing problem with fuzzy demands (clrp_fd) is considered. in clrp_fd, facility location problem (flp) and vehicle routing problem (vrp) are observed simultaneously. indeed the vehicles and the depots have a predefined capacity to serve the customerst...

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 ...

The purpose of this paper is to introduce the area of Green Logistics and to describe some of the problems that arise in this subject which can be formulated as combinatorial optimization problems. The paper particularly considers the topics of reverse logistics, waste management and vehicle routing and scheduling.

Vehicle Routing Problem (VRP) is a hot issue in the field of logistics. Furthermore, the Vehicle Routing Problem with Time-Windows (VRPTW) is an additional constraint of the customer access time windows based on the VRP. It becomes a noticeable problem with the development of logistics distribution and the just-intime distribution demand from customers, which increases a visiting window to trad...

The emergence of metaheuristics for solving diÆcult combinatorial optimization problems is one of the most notable achievements of the last two decades in operations research. This paper provides an account of the most recent developments in the eld and identi es some common issues and trends. Examples of applications are also reported for vehicle routing and scheduling problems.