Economic production quantity for fuzzy demand quantity and fuzzy production quantity

In the fundamental production inventory model, in order to solve the economic production quantity (EPQ) per cycle we always fix both the demand quantity and the production quantity per day. But, in the real situation, both of them probably will have little disturbances every day. Therefore, we should fuzzify both of them to solve the economic production quantity (q*) per cycle. The purpose of this paper is to investigate a computing schema for the EPQ in the fuzzy sense. We find that, after defuzzification, the total cost is although slightly higher than in the crisp model; however, it permits better use of the EPQ in the crisp arising with little disturbances in the production, and demand. (C) 1998 Elsevier Science B.V.