A TRAVELING SALESMAN MODEL FOR THE SEQUENCING OF DUTIES IN BUS CREW ROTAS

The paper addresses one aspect of the rostering problem posed to the p ublic transport company operating in Porto, Portugal. The specific pro blem dealt with in this paper is that of sequencing the duties within each rota (rotating schedule) so as to minimize the variance of the re st periods between successive duties while satisfying constraints on t heir minimum value. This problem is formulated as a travelling salesma n problem. Solutions derived from two heuristics are compared with the optimal ones.