“…Step 2: using (1) to identify the optimum values of x k , k ¼ 1, 2, … which would bring the output characteristic y to target t. Since there are multiple output characteristics, identify the optimum values of x k , k¼ 1, 2, …, which would simultaneously bring multiple output characteristics y l , l ¼ 1, 2, … to respective targets t l . This can be achieved through a multiple response optimization methodology, namely, Derringer's desirability function methodology (Derringer, 1994;John, 2013;Goethals and Cho, 2011), Taguchi's loss function approach (Wu, 2002;Antony et al, 2006;John, 2012;Reddy et al, 1998), gray relational analysis (Saha and Mandal, 2013), data envelopment method (Liao, 2004;Liao and Chen, 2002), mean square criteria (Koksoy and Yalcinoz, 2006;John et al, 2017), neural networks (Hsu, 2004), etc. In this study, the fuzzy logic methodology is used for simultaneously optimizing the output characteristics.…”