We present an integer programming model for the ferry scheduling problem, improving existing models in various ways. In particular, our model has reduced size in terms of the number of variables and constraints compared to existing models by a factor of approximately O(n), where n being the number of ports. The model also handles efficiently load/unload time constraints, crew scheduling and pas...

We present the problem of planning mobile tours of inspectors on German motorways to enforce the payment of the toll for heavy good trucks. This is a special type of vehicle routing problem with the objective to conduct as good inspections as possible on the complete network. In addition, we developed a personalized crew rostering model, to schedule the crews of the tours. The planning of daily...

Rostering is a crucial planning process in an airline’s overall scheduling hierarchy. Besides addressing the issues of crew utilisation and crew costs (which represent two of the major expenses in running an airline), a rostering tool must also cover the question of quality requirements. The quality of service can be improved by having the rostering tool take into consideration the skills of in...

Tourism is a service-intensive industry that is characterized by a highly competitive market. The adequate utilization of personnel provides the key means of tackling two conflicting tendencies: on the one hand, the consumers’ expections of a certain level of service quality; on the other, the expense usually associated with qualified human labor. Our paper presents (1) how the quality level of...

Bus transit network planning is a complex process that is divided into several phases such as: line planning, timetable generation, vehicle scheduling, and crew scheduling. In this work, we address the timetable generation which consists in scheduling the departure times for all trips of each bus line. We focus on the Synchronization Bus Timetabling Problem (SBTP) that favors passenger transfer...

The set covering problem (SCP) is one of representative combinatorial optimization problems, which has many practical applications. The continuous development of mathematical programming has derived a number of impressive heuristic algorithms as well as exact branch-and-bound algorithms, which can solve huge SCP instances of bus, railway and airline crew scheduling problems. We survey heuristic...

A wide spectrum of “real world” problems, such as vehicle routing, machine and crew scheduling, facility location, portfolio analysis, electricity generation planning, and communication and transportation network design, demands the use of combinatorial optimization methods. By a combinatorial optimization problem, we mean a program where a linear or nonlinear objective function must be optimiz...