Periodic transportation schedules with flexible departure times

The authors consider a procedure for constructing periodic transportation schedules with a minimal number of resources (aircraft), in which the flights have flexible departure times, set-up times between them, and special precedence relations. The present approach is based on an interactive use of two approaches: (1)the periodic event scheduling problem (PESP), (2)the visual display of the so called deficit functions (DF). The DF’s allow to create cycles of flights and to evaluate the number of resources; the PESP receives these cycles as an input and tries to find out a feasible schedule with respect to all constraints involved. The output of PESP is either a feasible schedule with fewer resources or recommendations for the constraint relaxation. The suggested procedure is meant to work interactively with a flight schedule expert.