Our paper:
Strategic Fleet Planning for City Logistics, authored by Anna Franceschetti, Dorothee Honhon, Gilbert Laporte, Tom Van Woensel and Jan Fransoo
is accepted for publication in Transportation Research, Part B.
In this paper, we study the strategic problem of a logistics service provider managing a (possibly heterogeneous) fleet of vehicles to serve a city in the presence of access restrictions. The problem is modelled as an area partitioning problem in which a rectangular service area has to be divided into sectors, each served by a single vehicle. The length of the routes, which depends on the dimension of the sectors and on customer density in the area, is calculated using a continuous approximation approach.
By doing so, we partition the service region and determine the type of vehicles (e.g. diesel or electric) to use in order to minimize the sum of ownership or leasing, transportation and labor costs.
We show that in some cases traffic restrictions may actually increase the number of vehicles on the streets, and we study the benefits of operating a heterogeneous fleet of vehicles. Numerically, we find that city access restrictions may, in some cases, be counter-productive because it may lead to an increase in the number of diesel vehicles and an increase in the total number of vehicles used in the service area.
We also show that on average, operating a heterogeneous fleet only leads to a small decrease in cost compared to operating a homogenous fleet. These cost decreases may however not be outweighed by the potential increase in logistical complexity resulting from operating several vehicle types.
The paper will be available at the website of the journal, or contact me directly for more information.