In this study, a new approach has been proposed for selecting appropriate maintenance strategies. For this purpose, decision making grid (DMG) has been developed. Sigma level and process capability indexes have been used based on the metric of mean time between failures (MTBF). The proposed...

In quality control, we may confront imprecise concepts. One case is a situation in which upper and lower specification limits (SLs) are imprecise. If we introduce vagueness into SLs, we face quite new, reasonable and interesting processes, and the ordinary capability indices are not appropriate...