Using detailed scheduling to obtain realistic operating policies for a batch processing facility

With many industries changing to a just-in-time manufacturing environment, the ability to reliably meet due dates and/or determine delivery/promise dates is gaining importance. In order to achieve this, the ability to determine operating policies based on realistic production plans is paramount. For these policies to be reasonable, the uncertain nature of the process must be addressed. These uncertainties include, but are not limited to, processing time fluctuations, equipment reliability/availability, process yields, demands, and manpower changes. In this paper we present a framework for addressing uncertainty by means of Monte Carlo sampling. This framework is not limited to a specific model, but results obtained show that the need of including sufficient detail is best satisfied by a scheduling model. A number of stopping criteria are derived, and the framework is utilized to obtain operating policies for two industrially-based examples.