Abstract:
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Rescheduling programmed tasks, when an unexpected event occurs, may affect the smooth operation of the
plant if the initial schedule is not taken into account. This work addresses the penalty incurred by rescheduling
actions and the optimization procedure to preserve schedule stability. To adjust the rescheduling process to
the needs of the decision-maker, rescheduling costs are included to the initial objective function. Namely,
unit reallocation and sequencing alterations are the sources of rescheduling costs. A mixed-integer linear
programming (MILP) model for the simultaneous rescheduling of multiple operations that permits local
reordering, unit reallocation, and accommodation of new orders, is considered. The need to consider
rescheduling penalties in the optimization procedure is highlighted through several case studies. As a result,
the production plant stability and efficiency are preserved, whereas the generation of pseudo-optimal schedules
is avoided. In addition, the tradeoff between the original objective function optimization and the smooth operation of the plant is thoroughly examinated. |