Evaluating and Selecting Two-Layers of Suppliers in Green Supply Chain using Hierarchical Fuzzy Topsis based on Alpha Levels

Developments in the world of business and new requirements leads to new attitudes which is considered essential for those involved in production and trade. New approaches and attitudes are developed about supply chain that leads to a green one.  The study examined two layer suppliers: first layer (providers of the parts and raw material directly to the manufacturer), and the second layer (providers of parts and raw material for the first layer) finally the study searched for the optimal supplier among them in each layer. To rank suppliers the below item were applieid: the concepts of first and second layers suppliers, green factor, using the proposed method entitled as s"second layer". Then their associated fuzzy numbers were calculated through Hierarchical Fuzzy TOPSIS method based on different levels of alpha. The study tries to establish a systematic approach for evaluating and selecting two layers of suppliers an dat he same time taking into account environmental factors. Manufacturer Stove Companies were the study sample.