A knowledge based approach to production scheduling for batch processes

Scheduling problem solving has escaped its initial attention on mathematical programming approaches and it is gaining benefits from other fields such as Discrete-Event simulation and Artificial Intelligence (AZ). The Al community has investigated the problem and most of its research focuses on the use of dispatching heuristic rules and constraint-satisfaction. This paper presents a different perspective. The similarities between the design and the multiproduct batch plant scheduling problems are analyzed, stressed and exploited; and a methodology based on a task-oriented approach is introduced. The scheduler is viewed as the ''designer'' of a production plan. Similar to the design problem, the ''final artifact'' is not known in advance and the complexity of the overall problem is tackled by means of decomposition. To accomplish it, the structure of the solution methodology is identified and explicitly conceptualized. The approach relies on the appropriate modeling of the scheduling scenario. An object-oriented modeling language is presented.