Economic lot scheduling of fully loaded processes with external setups

Without restricting the class of permissble schedules, the authors derive optimal schedules for economic lot scheduling problems that are fully loaded, have external setups, and have only two products. The fully loaded condition accurately represents certain types of bottlenecks. The authors show that the optimal schedule must have the Wagner-Whitin property. They also develop a measure of aggregate inventory, derive an optimal steady-state aggregate inventory policy, and provide conditions under which the aggregate inventory level of an optimal schedule must approach a steady state. By restricting the class of permissible schedules to rotation cycle schedules, the authors extend these results to more than two products.