Dynamic scheduling of product-mix production systems of MTS and MTO

摘要

This paper discussed real-time solutions to product-mix scheduling problems (PMSPs) when a loading or a capacity of Fab are dynamically changing. The objective is that maximization of the resource utilization while keeping a due date and Q-time restrictions of every production lot. Particularly, two methods, P3D (Pseudo-Periodically Priority Dispatching) and the Palmer, are introduced for Make-to-Stock (MTS) and Make-to-Order (MTO) productions. After P3D's capabilities and limits about using demand forecasting are discussed, we newly introduced EDD-Palmer dispatching for product-mix MTO production for a case the demand prediction is difficult. The EDD-Palmer method evaluated for an actual wafer test process by comparing with EDD and EDD-CDS methods. This paper was concentrated in an optimal work leveling and dispatching of MTO WIPs.