Process capability analysis using intuitionistic fuzzy sets

Article type: Research Article

Authors: Kahraman, Cengiz^{a; *} | Parchami, Abbas^b | Cevik Onar, Sezi^a | Oztaysi, Basar^a

Affiliations: [a] Department of Industrial Engineering, Istanbul Technical University, Macka Istanbul, Turkey | [b] Department of Statistics, Faculty of Mathematics and Computer Sciences, Shahid Bahonar University of Kerman, Kerman, Iran

Correspondence: [*] Corresponding author. Cengiz Kahraman, Istanbul Technical University, Department of Industrial Engineering, 34367 Macka Istanbul, Turkey. Tel.: +90 212 293 13 00; (Ext. 2035); Fax: +90 212 240 72 60; E-mail: kahramanc@itu.edu.tr.

Abstract: The process capability analysis aims at measuring the capability degree of the process distribution in meeting the specification limits. Process capability indices are used to indicate the capability degree of a process. A process whose distribution falls inside the specification limits is a capable process and its capability indices are at least 1. In case of vague and imprecise information, process capability analyses have been extended by using ordinary fuzzy sets in the literature. In this paper we extend the fuzzy process capability analysis from ordinary fuzzy sets to intuitionistic fuzzy sets. We realize this extension by using both intuitionistic fuzzy numbers and interval-valued intuitionistic fuzzy sets. We also propose defuzzification methods for intuitionistic fuzzy numbers and interval-valued intuitionistic fuzzy sets. Numerical examples show the applications of the proposed analyses and help the readers understand them.

Keywords: Process capability, intuitionistic, fuzzy set, fuzzy number, interval-valued, defuzzification

DOI: 10.3233/JIFS-141877

Journal: Journal of Intelligent & Fuzzy Systems, vol. 32, no. 3, pp. 1659-1671, 2017