The paper proposes and validates a new method of solving instances of the vehicle routing problem (VRP). The approach is based on a multiple agent system paradigm. The paper contains the VRP formulation, an overview of the multiple agent environment used and a description of the proposed implementation. The approach is validated experimentally. The experiment plan and the discussion of experime...

We have previously shown that delivery of the porcine type I interferon gene (poIFN-α/β) with a replication-defective human adenovirus vector (adenovirus 5 [Ad5]) can sterilely protect swine challenged with foot-and-mouth disease virus (FMDV) 1 day later. However, the need of relatively high doses of Ad5 limits the applicability of such a control strategy in the livestock industry. Venezuelan e...

Dendritic cells (DCs) are a diverse population with the capacity to respond to a variety of pathogens. Because of their critical role in pathogenesis and Ag-specific adaptive immune responses, DCs are the focus of extensive study and incorporation into a variety of immunotherapeutic strategies. The diversity of DC subsets imposes a substantial challenge to the successful development of DC-based...

A key element of many distribution systems is the routing and scheduling of vehicles through a set of nodes requiring service. The Vehicle Routing Problem (VRP) can be defined as a problem of finding the optimal routes of delivery or collection from one or several depots to a number of cities or customers, while satisfying some constraints. In many practical situations, however, the vehicle is ...

In this paper we introduce a robust optimization approach to solve the Vehicle Routing Problem (VRP) with demand uncertainty. This approach yields routes that minimize transportation costs while satisfying all demands in a given bounded uncertainty set. We show that for the Miller-Tucker-Zemlin formulation of the VRP and specific uncertainty sets, solving for the robust solution is no more diff...

The number of optimization techniques in the combinatorial domain is large and diversified. Nevertheless, there is still a lack of real benchmarks to validate optimization algorithms. In this work we introduce VRPBench, a tool to create instances and visualize solutions to the Vehicle Routing Problem (VRP) in a planar graph embedded in the Euclidean 2D space. We use VRPBench to model a real-wor...

It is well known that the Vehicle Routing Problem (VRP) becomes more difficult to solve as the problem size increases. However little is known about what makes a VRP difficult or easy to solve for problems of the same size. In this paper we investigate the effect of the formulation and data parameters on the efficiency with which we can obtain exact solutions to the VRP with a general IP solver...

Abstract In the classic Vehicle Routing Problem (VRP) a fleet of of vehicles has to visit a set of customers while minimising the operations’ costs. We study a rich variant of the VRP featuring split deliveries, an heterogeneous fleet, and vehiclecommodity incompatibility constraints. Our goal is twofold: define the cheapest routing and the most adequate fleet. To do so, we split the problem in...

In this paper, we address the Two-Echelon Vehicle Routing Problem (2E-VRP) in which freight is delivered from depots to intermediary satellites, from where it is delivered to customers. Different from other multi-level problems, the focus in 2E-VRP is on the global routing costs of the overall network. 2E-VRP has been recently introduced and, to our knowledge, there are no studies of the impact...

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...