POLYTECHNIC INST OF NEW YORK BROOKLYN DEPT OF ELECTRICAL ENGINEERING AND ELECTROPHYSICS
This paper develops bounds on the uncertainties in system availabilities or reliabilities which have been computed from structural series, parallel, etc. relations among uncertain subsystem availabilities or reliabilities. It is assumed that the highly available reliable subsystems have been tested or simulated to determine their unavailabilities unreliabilities to within some small percentages of uncertainty. It is shown that series, parallel and r out of n structures which are nominally highly available will have unavailability uncertainties whose percentage errors are of the same order as the subsystem uncertainties. Thus overall system analysis errors, even for large systems, are of the same order of magnitude as the uncertainties in the component probabilities. Both systematic bias type uncertainties and independent random uncertainties are considered.