Optimal supply planning for two-levels assembly system with stochastic lead-times and maintenance actions

This paper deals with the supply planning for two level assembly systems under stochastic lead time and random failure machine. The objective is to determine the optimal supply planning of the assembly system while considering the maintenance actions and then to study their impact on the optimal release dates for the components at level 2. The optimal supply planning minimizes the total cost which is the sum of inventory holding cost for components at level 1 and 2, assembly cost, maintenance cost, backlogging and inventory holding cost for the finished product. A mathematical model is proposed to compute the total cost and then to determine the optimal supply planning. Numerical results are presented to discuss the impact of maintenance actions on the optimal release dates.