University of Sistan and BaluchestanIranian Journal of Fuzzy Systems1735-065416520191001An EPQ model for an imperfect production process with fuzzy cycle time and quality screening169185491710.22111/ijfs.2019.4917ENH.OzturkSuleyman Demirel University, Department of Business Administration, 32260, Isparta, TurkeyS.AytarSuleyman Demirel University, Department of Mathematics, 32260, Isparta, TurkeyF. A.SenelSuleyman Demirel University, Department of Computer Engineering, , 32260, Isparta, TurkeyJournal Article20171217This study has developed a production inventory model where the cycle time<br />is fuzzy, the existence of defective products is assumed in each batch and<br />product screening is performed both in-production and after-production.<br />Triangular fuzzy numbers serve to model uncertainties in the cycle time, and<br />a fuzzified total inventory profit function is created by the<br />defuzzification method known as the signed distance method. The classical<br />approach is used to determine the optimal policy, with the ideal cycle time<br />matched to the total profit. Although assuming asymmetric triangular fuzzy<br />numbers prevents the calculation of a clear analytical solution, the method<br />approaches as closely as possible to an analytical solution. A numerical<br />solution to only one equation is needed to obtain the optimal configuration.<br />Conversely, there is a positive trade-off, with an analytical solution to<br />the optimization problem if there is an assumption of symmetrical triangular<br />fuzzy numbers. The proposed model is illustrated by a numerical example. The<br />paper presents results and sensitivity analyses, in both tables and graphic<br />illustrations. The effects on total profit are discussed in relation to<br />various parameters. From the numerical studies, it is observed that the<br />level of fuzziness influences the cycle time and an approximately linear<br />relationship, in the opposite direction, was found between the total profit<br />and the level of fuzziness, when it was increased.http://ijfs.usb.ac.ir/article_4917_f35adbb35a642aa550f75bfc3a19b493.pdf