We consider a two-stage production-inventory system with demand at the downstream stage and returns at each stage. We characterize the structure of the optimal policy which is a complex state-dependent Base-stock policy. We also investigate four classes of policies : Fixed buffer, Base-stock echelon, Kanban and Half-optimal. We compare the performances of these policies and exhibit that the max...

We consider a serial inventory system with N stages. The material flows from an outside supplier to stage N, then to stage N0 1, etc., and finally to stage 1 where random customer demand arises. Each stage replenishes a stage-specific inventory position according to a stagespecific reorder point/order quantity policy. Two variations of this policy are considered. One is based on echelon stock, ...

T paper studies a periodic-review, serial supply chain in which materials are ordered and shipped according to R nQ policies. Three information scenarios are considered, depending on the level of information available: echelon, local, and quasilocal. In the echelon scenario, each stage can access the inventory and cost information within its echelon (comprising the stage itself and all downstre...

In this paper, for effective multi-echelon supply chains under stochastic and fuzzy environments, an inventory management framework and deterministic/stochastic-neuro-fuzzy cost models within the context of this framework are structured. Then, a numerical application in a three-echelon tree-structure chain is presented to show the applicability and performance of proposed framework. It can be s...

This paper analyzes a series inventory system with stationary costs and stochastic demand over an infinite horizon. A distinctive feature is that demand can be negative, representing returns from customers, as well as zero or positive. We observe that, as in a system with nonnegative demand, a stationary echelon base-stock policy is optimal here. However, the steadystate behavior of the system ...