A Preventive Maintenance Model Subject to Sequential Inspection for a Three-Stage Failure Process
Xiaoxiao Caoa, Chao Guoa, Huasheng Xiongabc*(), Duo Lib, and Xiaojin Huangc

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Figure 4.. (a) Opportunisticreplacement is Implemented at${{S}_{{{A}_{n}}+i+1}}+\tau $; (b) Opportunisticreplacement is performed at ${{S}_{{{A}_{n}}+m+1}}+\tau $