For regular patient transportation and emergency transportation with ambulance vehicles a dy-namic dial-a-ride (DARP) problem has to be solved. We analyze two scheduling strategies for theregular dial-a-ride orders in order to minimize routing costs and to maximize transportation qual-ity. Furthermore, we review practical requirements and suggest a conceptual architecture for a<...

Vehicle Routing Problem (VRP) is a key element of many transportation systems which involve routing of fleet of vehicles from a depot to a set of customers node. It is required that these vehicles return to the depot after serving customers’ demand. This paper investigates a relaxed version of VRP, in which the number of visits to the customer is not restricted to be at most one. The relaxed ve...

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...

Today, one of the new technologies in the modern era is Vehicular Ad-hoc Network which has takenenormous attention in the recent years. Because of rapid topology changing and frequent disconnectionmakes it difficult to design an efficient routing protocol for routing data between vehicles, called V2V orvehicle to vehicle communication and vehicle to roadside infrastructure, called V2I. Designin...

The global growth in urbanisation increases the demand for services including road transport infrastructure, presenting challenges in terms of mobility. These trends are occurring in the context of concerns around environmental issues of poor air quality and transport related carbon dioxide emissions. One out of several ways to help meet these challenges is in the intelligent routing of road tr...

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. ...

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 ...

This paper addresses the essential elements and strategies that should be in place for large-scale evacuations under emergency situations, particularly in densely used networks such as in Toronto, Ottawa, Vancouver and Montreal to name a few. Some questions that possess some indispensable information to achieve that goal are proposed. A novel framework that addresses these questions is proposed...

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...