Spatial Localization and Statistical Classification of Nonlinear Ultrasonic Signature in Bio-Mechanical Medium with Time Reversal Based News Methods

0422107 - ÚT 2014 SG eng A - Abstrakt
Farová, Zuzana - Dos Santos, S. - Převorovský, Zdeněk - Kůs, V.
Spatial Localization and Statistical Classification of Nonlinear Ultrasonic Signature in Bio-Mechanical Medium with Time Reversal Based News Methods.
International Congress on ULTRASONICS : ICU 2013. Singapore, 2013. s. 80-81.
[International Congress on ULTRASONICS. 02.05.2013-05.05.2013, Singapore]
Institucionální podpora: RVO:61388998
Klíčová slova: time-reversal * chirp excitation * classification * phi-divergence
Kód oboru RIV: BI - Akustika a kmity

This paper investigates possibilities of localization and statistical classification of ultrasonic nonlinearities in biomedical complex media. Time Reversal (TR) approach in combination with Nonlinear Elastic Wave Spectroscopy (NEWS) is used in order to obtain nonlinear signature of damages in a tooth, air bubbles in liquid, and Ultrasound Contrast Agents (UCA). The classification of ultrasonic signals is performed by means of a fuzzy classification method, in which parameters like Φ-divergence are extracted from the received ultrasonic response containing acoustic nonlinearities. According to the classification results, several types of nonlinearities extracted with classical Pulse Inversion (PI) based coding methods are identified and position of the scattered sources in the complex media are also approximately found. Several suggested experiments are described. By using of fuzzy classification method with the suggested parameters obtained from direct and TR responses, we are able to separate different sources of nonlinearities in a feature space and also to separate scattered nonlinearities which come from different positions in the media.
Trvalý link: http://hdl.handle.net/11104/0228789