ROBUST SCHEDULING WITH PROCESSING TIME UNCERTAINTY

The scheduling of batch chemical processes has been the focus of a sub stantial amount of research interest. Work to date has focused primari ly on building schedules for processes which are assumed to operate in a deterministic manner. In real world chemical processing facilities uncertainty exists in all facets of the manufacturing environment. The deviations which are considered in this work are those which can be r epresented as processing time variations. A framework is presented whi ch when used open-loop is an effective tool for evaluating the expecte d performance and robustness of various scheduling strategies. Two sch eduling tools are compared, one which uses the uniform time discretize d model and the other uses a non uniform discretization of time.