a direct solution approach to supply chain network design with fuzzy decision variables

one of the main problems of supply chain network design is uncertainty. to consider this, designing of a three-echelon supply chain in a fuzzy environment is discussed in this paper. since satisfaction of some constraints in supply chain is vital and necessary, so this research proposes a direct solution approach to find the solution which represents the trade-off between feasibility degree of constraints and satisfaction degree of the goal. furthermore, another novation of this paper is optimizing a supply chain network design problem containing both of the parameters and decision variables as fuzzy number. each fuzzy mathematical programming model with fuzzy decision variables can be solved effectively by employing direct solution approach. a numerical example is discussed and analyzed in order to show efficiency of the proposed approach.