Check-in computation and optimization by simulation and IP in combination

This paper presents and investigates a check-in problem for a twofold reason: (i) as a problem of practical and novel scientific interest in itself and (ii) as a problem which requires both a stochastic (simulation) and deterministic (integer programming) approach. First, simulation is used to determine minimal numbers of desks in order to meet a service level for each separate flight. Next, integer programming formulations are provided to minimize the total number of desks and the total number of desk hours under the realistic constraint that desks for one and the same flight should be adjacent. Both opening intervals with constant and variable capacities will be studied. A numerical example of real world order shows a triple win in waiting time performance, in number of desks and in number of desk hours (staffing). As simulation and integer programming tools are widely available, this combination of simulation and integer programming can thus be regarded as an illustration of a ‘new’ practical OR-tool for optimization.