Release Date Optimization Using Clearing Functions in MRP

Abstract: This paper integrates a clearing function (CF)-based release planning approach into Material Requirements Planning (MRP) to address its limitations in modeling capacity constraints and dynamic lead times. The proposed CF-based optimization model replaces MRP's backward scheduling step while preserving its overall structure. Performance is evaluated through simulation experiments on two flow shop systems: a compact three-level system with three shared resources (PS1) and a more complex four-stage system with 32 end items and 16 machines (PS2). The experiments explore a range of demand uncertainties and utilization levels. Results show that CF-based planning consistently reduces total costs and tardiness while improving schedule feasibility, particularly under imperfect forecasts. These findings demonstrate the potential of CFs to enhance MRP by introducing workload responsiveness and dynamic adaptability, without compromising computational tractability.