Strengthening discrete-time scheduling formulations by introducing the concept of campaigns

Discrete-time, Mixed-Integer Linear Programming (MILP) models are frequently used for scheduling problems in which the utilization of resources and/or the determination of costs and revenues imply complex time-dependent functions that are directly related to the development of the tasks. One of the main challenges in these models is to deal with changeovers, which are one of the most complicating features. In this short note, we provide some insight to effectively model the scheduling of operations by means of the concept of campaigns. We show that this allows to reduce the computational burden by three orders of magnitude when compared to conventional approaches. (C) 2020 Elsevier Ltd. All rights reserved.