Decision theory in maintenance strategy for a 2-unit redundant standby system

Obtaining a good maintenance strategy for a standby system is discussed. The problem is analyzed via decision theory to determine the waiting time to call the repair facility (for a two-unit standby system) when the first piece of equipment fails. Previous research into this kind of system is briefly described, and a need for constructing a decision model is explained. The uncertainty of the parameters is accounted for in a Bayes approach in order to consider expert prior knowledge. The failure and repair rates are assumed to be constant and are elicited from an expert's prior beliefs. When no data are available, expert guesses are used. A method is presented for solving the conflicting requirements of system availability and cost through a multiattribute utility function which can express cardinal values for the decision maker's preferences over the objective variables. The decision model derives the appropriate maintenance strategy; it corresponds to a set of actions, procedures, and resources, giving a consequent waiting time before calling the repair facility. The use of the model is demonstrated for a telecommunication system. >