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Accession Number ADA564933
Title Statistical Analysis of Eddy Current Data from Fastener Site Inspections (Preprint).
Publication Date Jul 2012
Media Count 24p
Personal Author I. Park J. C. Aldrin J. S. Knopp R. V. Grandhi
Abstract Recent work on reliably detecting and characterizing cracks in multi- layer airframe structures has used modeling and simulation to extract features from raw eddy current data, and to assist in the evaluation of probability of detection (POD). This paper focuses on the statistical analysis of the data from these studies. Hit/miss, linear, and physics-inspired methods are employed to evaluate POD. The Box-Cox transformation is used as a remedy for violations of homoscedasticity. In addition, a bootstrapping method is introduced for confidence bound calculation on a 2nd order linear model. The objective of this work is to provide on insight how different models and assumptions impact POD evaluation.
Keywords Airframes
Box cox transformation
Crack propagation
Eddy currents
Nondestructive testing
Probability of detection
Statistical analysis

Source Agency Non Paid ADAS
NTIS Subject Category 72F - Statistical Analysis
46 - Physics
Corporate Author Air Force Research Lab., Wright-Patterson AFB, OH. Materials and Manufacturing Directorate.
Document Type Technical report
Title Note Interim rept. 1 Jun-1 Jul 2012.
NTIS Issue Number 1304
Contract Number N/A

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