Time reversal based news methods for localization and classification of nonlinear vibrations in bio-mechanical media

0423164 - ÚT 2014 RIV TH eng C - Conference Paper (international conference)
Dos Santos, S. - Farová, Zuzana - Kůs, V. - Převorovský, Zdeněk
Time reversal based news methods for localization and classification of nonlinear vibrations in bio-mechanical media.
20th International Congress on Sound & Vibration : ICSV 20. Bangkok: International Institute of Acoustics and Vibration, 2013 - (Crocker, M.; Pawelczyk, M.), s. 1-8. ISBN 978-616-551-682-2. ISSN 2329-3675.
[International Congress on Sound & Vibration /20./. Bangkok (TH), 07.07.2013-11.07.2013]
Institutional support: RVO:61388998
Keywords : time reversal * statistical classification * chirp excitation
Subject RIV: BB - Applied Statistics, Operational Research

Non Destructive Testing (NDT) and harmonic medical imaging methods have been widely developed thanks to the use of the symbiosis of Time Reversal (TR) based signal processing tools and Nonlinear Elastic Wave Spectroscopy (NEWS) methods. Statistical methods for classification, identification and localization were developed in order to detect, localize and calibrate nonlinear scatterers responsible of the structural degradation of materials. The classification of nonlinear vibrations is performed by means of a fuzzy classification method, in which parameters are extracted from the ultrasonic response containing acoustic nonlinearities. According to the classification results, several types of nonlinearities extracted with Pulse Inversion (PI) based methods are identified, and position of the scattered sources are found. The experimental feasibility of a focused TR-NEWS method has been improved with a set-up taking into account new advanced chirpcoded excitations, and new statistical classification.
Permanent Link: http://hdl.handle.net/11104/0229592