In this paper, we consider two-tier City Logistics systems accounting for both the inbound and outbound traffic that have not been taken into account in models and algorithms for vehicle routing research. The problem under study, called the Multi-zone Multi-trip Pickup and Delivery Problem with Time Windows and Synchronization, has two sets of intertwined decisions: the routing decisions which ...

Transportation in economic systems such as services, production and distribution enjoys a special and important position and provides a significant portion of the country's gross domestic product. Improvements in transportation system mean improvements in the traveling routes and the elimination of unnecessary distances in any system. The Vehicle Routing Problem (VRP) is one of the practical co...

This thesis considers the Dynamic Pickup and Delivery Problem (DPDP), a dynamic multi-stage vehicle routing problem in which each demand requires two spatially separated services: pickup service at its source location and then delivery service at its destination location. The Dynamic Pickup and Delivery Problem arises in many practical applications, including taxi and courier services, manufact...

A new model and solution for the energy minimizing vehicle routing problem with time windows (EVRPTW) and customers’ priority is presented in this paper. In this paper unlike prior attempts to minimize cost by minimizing overall traveling distance, the model also incorporates energy minimizing which meets the latest requirements of green logistics. This paper includes the vehicles load as an ad...

We address in this article the multi-commodity pickup-and-delivery traveling salesman problem, which is a routing problem for a capacitated vehicle that has to serve a set of customers that provide or require certain amounts of m different products. Each customer must be visited exactly once by the vehicle, and it is assumed that a unit of a product collected from a customer can be supplied to ...

We address in this paper the pickup and delivery multi-depot vehicle routing problem (PDMDVRP). In this problem, a single commodity type is collected from a set of pickup customers to be delivered to a set of delivery customers by vehicles dispatched from multiple depots. The proposed problem has many applications in practice such as distribution of money between the branches of a bank, and mov...

The development of effective decision support tools that can be adopted in the transportation industry is vital in the world we live in today, since it can lead to substantial cost reduction and efficient resource consumption. Solving the Vehicle Routing Problem (VRP) and its related variants is at the heart of scientific research for optimizing logistic planning. One important variant of the V...

This paper considers a single-vehicle Dial-a-Ride problem in which customers may experience stochastic delays at their pickup locations. If a customer is absent when the vehicle serves the pickup location, the request is fulfilled by an alternative service (e.g., a taxi) whose cost is added to the total cost of the tour. In this case, the vehicle skips the corresponding delivery location, which...

The Fixed Routes Problem is a variation of the Vehicle Routing Problem in which the routes that have to be constructed will be operated unchanged for an extended period of time while the customer demands within that period will vary. If, in a delivery scenario, a vehicle cannot satisfy the demand of a customer it musts return to the depot for replenishment before continuing its route. The fixed...