This paper provides an assessment on the impact of collaboration and smoothing replenishment rules on supply chain operational performance and customer service level. Three supply chain configurations (i.e. Traditional, Information Exchange and Synchronised) in which orders are generated by smoothing (S, R) inventory control policies, are studied for variations of proportional controller for di...

Inventory pooling is at the root of many celebrated ideas in operations management. Postponement, component commonality, and resource flexibility are some examples. Motivated by our experience in the after-market services industry, we propose a model of inventory pooling to meet differentiated service levels for multiple customers. Our central research question is the following: What are the mi...

We analyze and compare three (s,S) inventory systems with positive service time and retrial of customers. In all of these systems, arrivals of customers form a Poisson process and service times are exponentially distributed. When the inventory level depletes to s due to services, an order of replenishment is placed. The lead-time follows an exponential distribution. In model I, an arriving cust...

Several surveys show that a significant number of customers leave retail stores because they cannot find the products for which they are looking (e.g. Most research in operations management focuses on two factors to explain lack of product availability—poor assortment and poor inventory planning. Our research with several retailers during the last few years highlights a third factor, poor execu...

This paper presents a mathematical model for an inventory control system in which customers’ demands and suppliers’ service time are considered as stochastic parameters. The proposed problem is solved through queuing theory for a single item. In this case, transitional probabilities are calculated in steady state. Afterward, the model is extended to the case of multi-item inventory systems. The...

One of the most important aspects affecting the performance of a supply chain is the management of inventories. Managing inventory in complex supply chains is typically difficult, and may have a significant impact on the customer service level and system-wide costs. The main challenge of inventory management is that almost every inventory problem involves multiple and conflicting objectives tha...

In partial backorder inventory system, when demand is not satisfied, unmet demand would be backordered partially. Either backorder or lost sales would make the cost increase. For a buyer, it is important to decide how much inventory should be prepared. A great deal of research efforts have been devoted to it over a few decades. Previous researches always assume that the lead time is fixed param...