Previous research on the joint economic lot size (JELS) problem was focused on the decisions of lot sizes and batches delivered among players in the supply chain, assuming that transportation cost was independent of shipment amounts. Nevertheless, the transportation cost accounts for a major part of supply chain cost, especially when transportation companies offer freight rate discount schedule...

In this paper we extend a stochastic discrete optimization approach so as to tackle the lot-sizing problem in manufacturing systems. In practice, with the surrogate methodology, the lot sizes are continuously adjusted on-line by the gradient-based approach. The lot sizing determines the number of parts batched together for production. We utilize the queueing approach that evidences the existenc...

In this research, a developed mathematical model is proposed to optimize the preventive maintenance age and lot size for a single-unit production system producing a single item. The system is assumed to start in an in-control state producing items of acceptable quality and then after a period of production time the system may shift to an out-of-control state producing non-conforming items. The ...