Abstract
In 1959 Dantzig and Ramser proposed a Vehicle Routing Problem (VRP). Since then developed and extended to varieties of problems in order to reflect contemporary requirements, distributing goods is a part of our daily life. No matter it is an overseas letter sent via FedEx, or a local product delivered by TAKKYUBIN, they all belong to distribution domain. Therefore, commodity distribution occurs anytime, everywhere, among countries, companies, and individuals.This study is focused on vehicle routing and scheduling problems, with different features considered for more realistic applications. These features include: multiple vehicle types for companies and multiple time windows for customers. In addition, to assist a logistic company in distributing goods effectively, the distribution costs that need to be minimized include vehicle dispatching cost, traveling cost, and time-window combination cost. In practice, the complexity of the problem makes it necessary to develop a structural model for facilitating a general analysis and applications. Such model has been developed and illustrated by two examples.Because the considered vehicle routing and scheduling problem with multiple vehicle types and multiple time windows (VRSP-MVMT) is a nondeterministic polynomial time (NP)-hard problem, we have developed a genetic algorithm (GA) for efficient solution. On one hand, when the problem is small-scale problem, the developed GA has shown to be capable of obtaining the optimal solution; on the other hand, when the scale of the problem is large, the GA can obtain the near-optimal solution. Finally, we will draw our conclusion regarding our study and future research.