Fascicolo 96/2000 Antonio Sforza, Presentation Luigi Biggiero, Massimo Di Gangi, An algoritm of incremental network loading with elastic demand and capacity constraints Maurizio Bruglieri, Francesco Zirilli, A mathematical model for railway schedule optimization when a network authority confronts several transportation companies Paolo Saitti, Dionisia Cazzaniga Francesetti, Competitive models for shipbuilding and the need for an integrated approach: a case study