Optimization of fuzzy production inventory model with unrepairable defective products

In this paper, we introduce a Fuzzy Economic Production Quantity (FEPQ) model with defective productions that cannot be repaired. In this model, we consider a fuzzy opportunity cost and trapezoidal fuzzy costs under crisp production quantity or fuzzy production quantity in order to extend the traditional production inventory model to the fuzzy environment. We use Function Principle as arithmetical operations of fuzzy total production inventory cost (FTPIC), and use the Graded Mean Integration Representation method to defuzzify the fuzzy total production and inventory cost. Then we use the Kuhn-Tucker method to find the optimal economic production quantity of the fuzzy production inventory model.