using fuzzy-robust approach for minimizing transportation and fuel costs in location problem under uncertainty

Operations research is a commonly used method in many subjects nowadays. One applicable domain of operation research is the problem of facility layout and location. In this paper، a new mathematical programing model is developed for an optimal facility location and assignment. The model includes two objective functions. The first one minimizes the total material handling and fixed costs of facility location. Because of the importance of energy and the main role of fossil fuel in transportation، the second objective function، minimizes the total cost of fuel consumption. To consider the real condition in the proposed model، the cost of fuel، is considered to increase stepwise gradually. In the proposed model the coefficients of objective function are considered to be probabilistic and some of constraints to be fuzzy variables. Using a new approach، this model can be changed to a robust model. To prove the applicability of the model، it is examined for a real condition of facility location.