Determining the optimum process mean for a mixed quality loss function

In 1999, Wen and Mergen adopted the step loss function of a product to balance the costs of out-of-specification occurrences and to determine the optimum process mean. They considered a normal quality characteristic and assumed a known standard deviation for the process in their model. This paper proposes a modified Wen and Mergen [1] model with a mixed quality loss function to determine the optimum process mean. The quality loss of the product per item includes a quadratic loss within specifications and an out-of-specification piecewise linear loss.