Trade-offs in just-in-time production planning for multi-stage systems: Balancing work-load variations and work-in-process inventories

Production planning for flow shops, job shops and projects has attracted much attention in the OR literature. This is not so for the comparatively new production environment of post-mass production, wherein a variety of end-product models is produced on high productivity equipment. As this production environment becomes increasingly dominant in many countries with small markets, such as Australia and New Zealand, there is a growing urgency for an OR analysis of its complex planning and scheduling problems. This paper presents a planning procedure for balancing workload variations and WIP inventories for an existing multi-stage processing facility in a post-mass production environment with discrete planning periods. The methodology is based on a multi-criteria production planning model which allows the facility to move towards JIT-processing at each processing stage without a full JIT commitment for the facility.