on time supply of materials in construction projects is very important. therefore, coordinating a project with key suppliers, while ensuring the timely supply of materials, make the minimum costs of project. one way to create this coordination is integrated inventory planning which has been accomplished in this study. it is necessary to mention that such a model is considered np_hard in terms o...

We present two integrated network design and inventory control problems in service-parts logistics systems. Such models are complicated due to demand uncertainty and highly nonlinear time-based service level constraints. Exploiting unique properties of the nonlinear constraints, we provide an equivalent linear formulation under part-warehouse service requirements, and an approximate linear form...

The relationship between demand and customer returns represents an important input to inventory planning models. While poor estimates of this relationship can dramatically increase inventory management costs (de Brito and van der Laan, 2002), there is surprisingly little research on the topic. In this paper we investigate the relationship between demand and returns by comparing how customers’ r...

Generally ordering policies are done by two methods, including fix order quantity (FOQ) and fix order period (FOP). These methods are static and either the quantity of ordering or the procedure of ordering is fixing in throughout time horizon. In real environments, demand is varying in any period and may be considered as uncertainty. When demand is variable in any period, the traditional and st...

Demand variability increases as one moves up a supply chain. The demand for finished products is less variable than for subassemblies, which is less variable than for individual components. This phenomenon is known as the bullwhip or Forrester effect. It increases inventory unnecessarily and makes managing the capacity of equipment and personnel difficult. In 1999, Philips Semiconductors confir...