We consider a vehicle routing problemwith a heterogeneous fleet of vehicles having various capacities, fixed costs and variable costs. An approach based on column generation (CG) is applied for its solution, hitherto successful only in the vehicle routing problem with time windows. A tight integer programming model is presented, the linear programming relaxation of which is solved by the CG tec...

The Sierra report proposes a methodology for states to use to demonstrate that their Inspection and Maintenance (I/M) programs are obtaining emissions reductions similar to those estimated by the MOBILE emissions factor model. The proposed methodology involves comparing fleetwide test average emissions of a state I/M program with those of a benchmark program (Sierra suggests using the Arizona I...

An optimization method for condition based maintenance (CBM) of aircraft fleet considering prognostics uncertainty is proposed. The CBM and dispatch process of aircraft fleet is analyzed first, and the alternative strategy sets for single aircraft are given. Then, the optimization problem of fleet CBM with lower maintenance cost and dispatch risk is translated to the combinatorial optimization ...

Although work-related driving is associated with high accident rates, limited research has investigated the factors influencing driving crashes in the work setting. This study explored multilevel influences on self-reported crashes in the workplace by surveying a sample of work-related drivers (n = 380), their workgroup supervisors (n = 88), and fleet managers (n = 47). At the driver level of a...

The purpose of this article is to propose a perturbation metaheuristic for the Vehicle Routing Problem with Private fleet and Common carrier (VRPPC). This problem consists of serving all customers such in a way that 1) each customer is served exactly once either by a private fleet vehicle or by a common carrier vehicle, 2) all routes associated with the private fleet start and end at the depot,...

Fleet Management Systems are commonly used to coordinate mobility and delivery services in a broad variety of domains. However, their traditional top-down control architecture becomes a bottleneck in open and dynamic environments, where scalability, proactiveness, and autonomy are becoming key factors for their success. In this paper, we first present an abstract event-based architecture for Fl...

Fleet planning is a process of strategic importance for an airline. Airlines have a tendency to match their capacities and passenger demand for corresponding market conditions, which has a direct impact on airline profitability and costs. It is necessary to consider many different factors in order to make a good fleet plan. This paper proposes the sequential two-stage model for fleet planning. ...

We present an optimization algorithm developed for a provider of software planning tools for distribution logistics companies. The algorithm computes a daily plan for a heterogeneous fleet of vehicles, that can depart from different depots and must visit a set of customers for delivery operations. Besides multiple capacities and time windows associated with depots and customers, the problem als...

We present a method of analyzing the relationships between driver characteristics and driving behaviors on the basis of fusing heterogeneous datasources with large-scale vehicle recorder data. It can be used, for example, by fleet managers to classify drivers by their skill level, safety, physical/mental fatigue, aggressiveness, and so on. Previous studies relied on precise data obtained in onl...

Nowadays genetic algorithms stand as a trend to solve NPcomplete and NP-hard problems. In this paper, we present a new hybrid metaheuristic which uses Parallel Genetic Algorithms and Scatter Search coupled with a decomposition-into-petals procedure for solving a class of Vehicle Routing and Scheduling Problems. The parallel genetic algorithm presented is based on the island model and was run on...