We consider the problem of finding the minimum number of vehicles required to visit once a set of nodes subject to time window constraints, for a homogeneous fleet of vehicles located at a common depot. This problem can be formulated as a network flow problem with additional time constraints....

The problem of assigning locomotives to trains consists of selecting the types and number of engines that minimize the fixed and operational locomotive costs resulting from providing sufficient power to pull trains on fixed schedules. The force required to pull a train is often expressed in...

This paper describes and solves the operational pilot scheduling problem for one day of operations. The problem consists in simultaneously modifying, as necessary, the existing flight departure schedules and planned individual work days (duties) while keeping planned aircraft itineraries...

Given the flight schedule of an airline, the fleet assignment problem consists of determining the aircraft type to assign to each flight leg in order to maximize the total expected profits while satisfying aircraft routing and availability constraints. The profit for a leg is a function of the...

We studied the following organization for the letter and parcel pick-up and delivery problem in an urban environment: the working day is divided in time periods during which each vehicle starts from a sorting center, travels to a precise area of the region, picks up and delivers letters and...

This paper considers the locomotive assignment problem encountered during the planning of the operations of a freight railroad, which consists of providing sufficient motive power to pull a set of scheduled trains at minimum cost while satisfying locomotive availability and maintenance...

In this paper, we present a sophisticated model and a heuristic solution approach based on mathematical optimization for the assignment of locomotives and cars to passenger trains. Given a periodic schedule and a fleet composed of several types of locomotives and cars, our approach determines a...

The model described determines airline flight schedules which will maximise company profits and passenger satisfaction. The approach represents a significant improvement in analytical methods for fleet planning and scheduling which take into account the complex interaction between the passenger...

Given a set of scheduled flights that must be operated by the same aircraft type, the aircraft routing problem consists of building anonymous aircraft routes that respect maintenance requirements and cover each flight exactly once. This paper looks at the nature of the problem and introduces a...