Abstract: In the traditional manufacture-customer supply-demand joint model, it is assumed that the lead time belongs to the negative exponential distribution in the time interval [0, ∞) and it only related to the customer. But in the real condition, the manufacturer generally plays an more important role than the customer in the supply chain, especially in the vendor-centralized supply chain. The manufacturer controls the operation of the supply chain and thus easily decides the behavior of the lead time. In this paper, it is assumed that the lead time belongs to the uniform distribution and the time interval of the lead time is decided by both the manufacturer and the customer in the supply chain. The lead time based joint inventory optimization model in the supply chain environment is established by combining their independent inventory model together and optimizing the model in the joint environment. The presented optimization method proves that the objective function has the minimum value at optimum order quantity and optimum order times in the lead time condition. The simulation shows that the proposed joint optimization method is always better than the independent optimization method.

Key words: supply chain, inventory, joint optimization, lead time