= Paula J. Dempsey
{c}
<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.<Gear Fault Detection Effectiveness as Applied to Tooth Surface Pitting Fatigue Damage by David G. Lewicki and others>[Gear Technology version, November/December2010, author biography, printed p.59]{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.<Gear Fault Detection Effectiveness as Applied to Tooth Surface Pitting Fatigue Damage by David G. Lewicki and others>[NASA report, printed pp.1–5, experimental data and indicator assessment; pp.4–5, quantitative detection analysis]{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.
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