Optimization of fuzzy backorder inventory models

Introduces two fuzzy backorder inventory models with fuzzy parameters and fuzzy variables. We use second function principle, graded mean integration representation method, and extension of the Lagrangean method to find optimal fuzzy economic order quantities and fuzzy economic shortage quantities of the fuzzy backorder inventory models. The solutions of fuzzy backorder inventory models are quite good and can be specified to meet the classical backorder inventory model by using these methods. We find that there are optimal crisp solutions in both fuzzy backorder inventory models with crisp order quantity and crisp shortage quantity, and with fuzzy order quantity and fuzzy shortage quantity