Composite cost-based rules for priority scheduling in a randomly routed job shop

This paper explores the effectiveness of composite time/cost priority-scheduling rules on both time and cost performance measures. These dispatching rules, based on value added or profitability, are compared, at various shop-utilization levels, against standard and modified time-based rules such as critical ratio and shortest processing time. The simulation of a randomly routed job shop shows that work in process can be significantly reduced with varying sacrifices in time-performance measures. At moderate levels of utilization, the results suggest that these dollar-based rules perform quite well. Both tabular and graphic, results are shown to clarify the tradeoffs which result.