Continuous-time formulations for multi-mode project scheduling

This paper reviews compact continuous-time formulations for the multi-mode resource-constrained project scheduling problem. Specifically, we first point out a serious flaw in an existing start-end-event-based formulation owing to inconsistent mode choices. We propose two options formulate missing constraints and consider equivalent reformulation with sparser constraint matrix. Second, aggregate variant of model that relies on on-off-events clarify role consistency issues such models. Third, suggest variants network flow formulation. enhance our models by adapting several techniques have been used previously, e.g., cases only single mode. A large set benchmark instances from literature provides basis up-to-date fair computational study out-of-the-box solver package. compare against literature. Our experiments assert confidently prevail test bed, they provide hint why event-based become less competitive settings.