C often face nonstationary demand due to product life cycles and seasonality, and nonstationary demand complicates supply chain managers’ inventory decisions. This paper proposes a simple heuristic for determining stocking levels in a serial inventory system. Unlike the exact optimization algorithm, the heuristic generates a near-optimal solution by solving a series of independent single-stage ...

– All-unit order frequency discount • 94%-effective policy for a variable base period – Incremental order frequency discount • 94%-effective policy for a fixed base period • 98%-effective policy for a variable base period Introduction • A supply chain is a network of facilities that procure raw materials, transform them into intermediate goods and then final products, and deliver the products t...

An arborescent distribution system is a multi-level system in which each installation receives input from a unique immediate predecessor and supplies one or more immediate successors. In this paper, it is shown that a distribution system with an arborescent structure can also be modelled using an echelon stock concept where at any instant the total echelon holding cost is accumulated at the sam...

In this study, inventory planning in logistics networks of modular products is investigated in a multi-period and multi-echelon setting. It is shown that this optimization problem can be converted to another problem which is briefly called modular proportional flow problem. This later problem is a minimum cost network flow problem with side constraints. The whole network consists of several dis...

We consider the planning and scheduling of production in a multi-task/multi-stage batch manufacturing process typical of industries such as chemical manufacturing, food processing, and oil refining. We allow instances in which multiple sequences of tasks may be used to produce end products. We formulate the problem as a mixed integer linear program and show that the linear programming relaxatio...

in this paper, we develop an inventory model for perishable items with random lifetime in a two-echelon production-distribution system. there is a manufacturer at the first stage that produces its product with a constant rate. deterioration in this stage is modeled via a two-parameter weibull distribution. at the second stage, the retailer places the order and receives the product instantly. th...

A comprehensive and integrated study of any supply chain (SC) environment is a vital requirement that can create various advantages for the SC owners. This consideration causes productive managing of the SC through its whole wide components from upstream suppliers to downstream retailers and customers.  On this issue, despite many valuable studies reported in the current literature, considerabl...

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...