Nonlinear ultrasonic properties

A noise and nonlinearity of thin and thick film resistors are used as rehabUity indicators to make a prediction of resistor rehabdity. The resistor noise is proportional to the current density and this property makes it a valuable characteristic for detecting imperfections and abnormaUties. The properties of thick fdm conducting layers were analyzed by Electro-Ultrasonic Spectroscopy. It is shown that intermodulation component is more sensitive to defects in resistors than non-linearity index NLL... 

Averkiou, M. A., Roundhill, D. N., and Powers, J. E (1997), A new imaging technique based on the nonlinear properties of tissues, IEEE Ultrasonics Syn sium Proceedings, pp. 1561-1566. 

Bacon, D.R. (1980) Properties of a PVDF hydrophone with 100 MHz bandwidth for studying medical, nonlinear and other fields. Proceedings of the IEEE Ultrasonics Symposium, Boston, MA, 5 7 November 1980, 582-5. 

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