We study a multi-item, two-echelon, continuous-review inventory problem at a Dutch utility company, Liander. We develop a model that optimizes the quantities of service parts and their allocation in the two-echelon network under an aggregate waiting time restriction. Specific aspects that we address are emergency shipments in case of stockout, and batching for regular replenishment orders at th...

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 ...

this paper aims to evaluate inventory cost of a two-echelon serial supply chain system under vendor managed inventory program with stochastic demand, and examine the effect of environmental factors on the cost of overall system. for this purpose, we consider a two-echelon serial supply chain with a manufacturer and a retailer. under vendor managed inventory program, the decision on inventory le...

The inventory management of multi-echelon repairable items systems is a major problem as these items are relatively expensive and slow-moving, so, inventory management can be a real problem due to mathematical complexities. In this work, a study was performed in a complex high-value products manufacturer, whose repairable items are both expensive and critical. Data of parts’ failure, storage an...

This paper analyses an infinite horizon two-echelon supply chain inventory problem and shows that a sequence of the optimum ordering policies does not yield globally optimal solutions for the overall supply chain. First-order autoregressive demand pattern is assumed and each participant adopts the order-up-to (OUT) policy with a minimum mean square error forecasting scheme to generate replenish...

The bullwhip effect is defined as the distortion of demand information as one moves upstream in the supply chain, causing severe inefficiencies in the whole supply chain. Although extensive research has been conducted to study the causes of the bullwhip effect and seek mitigation solutions with respect to several demand processes, less attention has been devoted to the ...

This paper focuses on the development of simulation-based environment for multi-echelon cyclic planning and optimisation in the product maturity phase. It is based on integration of analytical and simulation techniques. Analytical techniques are used to obtain initial planning decisions under conditions of stochastic demand and lead time, whereas simulation techniques extend these conditions to...

We analyze a multi-echelon inventory system with inventory stages arranged in series. In addition to traditional forward material flows, used products are returned to a recovery facility, where they can be stored, disposed, or remanufactured and shipped to one of the stages to reenter the forward flow of material. This system combines the key elements of two simpler systems: the series system s...