Most periodic review models in the inventory literature have assumed a fixed length of the review periods. In this note …, we extend the work of Chiang (2008) , and consider backlogged and lost-sales periodic review models where the review …) policy is optimal for the infinite horizon problem. The periodic review policies developed are thus easy to implement. The …

. We propose a single item lost sales model with a lead time of zero, periodic review and nonlinear non-stationary cost …