A new robust model for location - Inventory in three echelon supply chain with uncertain demand in small and medium business enterprises

Today, with changing patterns of production and services competition, independent companies are faced with competition between supply chains. Most of the small and medium businesses (SMEs) are still used to the traditional supply planning, production and distribution. It means, each of these SMEs plan independently for their activities, in most cases, this will increase the cost of the whole supply chain. In this study, we present a robust model of location, inventory in three-echelon supply chain under uncertainty. Model has been considered in single-period, multi-product, multi-mode transportation with three level producers - distributors-retailers in certain and robust mode. The innovation of this article are considering multi-mode transportation, rousting the model and sending the goods directly from the factory to the retailer. The objective of the proposed model is minimising the total cost of the three-echelon supply chain. The certain model is solved by GAMS and robust model is solved by GAMS and augmented ε-constraint method.