 Paula J. Dempsey

Paula J. Dempsey is an engineer whose documented research concerns fault detection and monitoring of aerospace propulsion and drive systems. Her2010 author biography identifies her as an aerospace research engineer at NASA Glenn, with mechanical- and industrial-engineering training. Her published work connects physical damage observations with the reliability of measured fault indicators.^[ref]

With David G. Lewicki, Gregory F. Heath and Perumal Shanthakumaran, Dempsey coauthored an evaluation of gear surface pitting detection using24 gear sets. The study compared vibration-based indicators with debris measurements from the oil circuit and checked the signals against observed damage. It used receiver operating characteristic analysis to examine the tradeoff between detecting a fault and raising a false alarm.^[ref]

For an illustrative dataset, a threshold that detects19 of20 damaged cases and flags2 of80 healthy cases has detection fraction $19/20=0.95$ and false-alarm fraction $2/80=0.025$. Raising the threshold can change both fractions. These example numbers are not results from the paper: they explain why a large vibration signal alone does not establish the quality of a detector. Dempsey's coauthored study addressed that distinction through repeated physical tests, rather than treating an indicator value as a direct measurement of damage.