OPTIMAL DISCRETE AND CONTINUOUS MAINTENANCE POLICY FOR A COMPLEX UNRELIABLE MACHINE

The failures of a complex unreliable machine depends on the age and th e maintenance action history. Failures can be reduced (in a probabilis tic sense) through effective maintenance actions. These maintenance ac tions can occur either at discrete time instants or continuously over time, Murthy (1984) dealt with a model that incorporates both these ty pes of maintenance action and derived optimal maintenance policies usi ng stochastic point process formulation and optimal control theory. Th is paper deals with a more general model. We give a complete character ization of the general model and derive some analytical results for tw o special cases.