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Inspection times for stand-by units

Published online by Cambridge University Press:  14 July 2016

Giovanni Parmigiani*
Affiliation:
Duke University
*
Postal address: Institute of Statistics and Decision Sciences, Duke University, Box 90251, Durham, NC 27708–0251, USA.

Abstract

This paper studies optimal timing of inspections for units in cold stand-by. The problem is approached in continuous time. The policies developed adapt optimally to information provided by failures of the main unit and by ageing of both the standby and the main unit.

Results include a general form for the optimal policy, consisting of a recursive relation between successive inspection times, and of a renewal-type integral equation to determine the value of the objective function for a given policy. Further results are derived for the case in which the failure densities describing the process are logconcave. Then the stopping rule is easily characterized. It is also shown that the interval between inspections decreases with time, and that the optimal schedule is unique. A binary search algorithm for finding the solution is outlined.

Type
Research Article
Copyright
Copyright © Applied Probability Trust 1994 

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