.../approach The study proposes the concept of grey-reliability index and built a decision support model, which can deal with the imprecise information for determining the minimum operational costs to plan subsequent maintenance efforts. Findings The findings of the study establish the synergy between...

... Grey system theory Grey relational analysis GM(1,N) model Maintenance Factor analysis Then following the weighted average grey relational degree expression, the grey relational degree of each comparison sequence could be given by: γ₁=0.7354, γ₂...