A Confidence Factor for SEA Results: a Comparison between Two Definitions based on Different Statistics

摘要

SEA provides the average of the power flow among modal groups of a system. As in any statistical approach, together with the average, some kind of variance would be required for a significant solution. This need was considered by Lyon who developed a computation to provide a confidence estimate , based on the probability distribution of modes in frequency bands. In the present work the analysis of a confidence factor, defined and used to describe the response of a system subjected to uncertainties in the physical parameters, is considered. Some results determined for the confidence factor are quite dissimilar from those obtained by Lyon. A theoretical comparative analysis between the two results is developed, together with Monte Carlo simulations that confirm the previous statement.