‎It is known that a system can be considered as a collection of components which are connected in some fashion for a specific‎ ‎purpose‎. ‎The main feature of a system is its activation and operation‎. ‎Therefore‎, ‎when an operating system is active‎, ‎its maintenance is important‎, ‎the problem is‎: ‎how can we maintain a system to increase its activation time? Also‎, ‎when a system fails‎, ‎the question is‎: ‎does the‎ ‎system need to be repaired‎, ‎or not? These problems have received considerable attention from many researchers‎. ‎In this work, ‎we are going to address these issues and explore some new strategies‎.

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