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arXiv · 2412.08655

Analysis of $(3+1)D$ and $(2+1)D$ nonlinear ultrasonic waves using conformal invariance

Sadataka Furui·Serge Dos Santos
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Abstract

Localization and classification of scattered nonlinear ultrasonic signatures in 2 dimensional complex damaged media using Time Reversal based Nonlinear Elastic Wave Spectroscopy (TR-NEWS) approach is extended to 3 dimensional complex damaged media. In (2+1)D, i.e. space 2 dimensional time 1 dimensional spacetime, we used quaternion bases for analyses, while in (3+1)D, we use biquaternion bases. The optimal weight function of the path of ultrasonic wave in (3+1)D lattice is obtained by using the Echo State Network (ESN) which is a Machine Learning technique. The hysteresis effect is incorporated by using the Preisach-Mayergoyz model. We analyze the spectrum data of Wire Arc Additive Manufacturing (WAAM) sample obtained by Quaternion Excitation Symmetry Analysis Method (QESAM) using the conformally invariant quantum mechanical variables of de Alfaro-Fubini-Furlan and their supersymmetrically extended variables of Fubini-Rabinovici.

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Sadataka Furui, Serge Dos Santos. 2024-11-27. Analysis of $(3+1)D$ and $(2+1)D$ nonlinear ultrasonic waves using conformal invariance. https://arxiv.org/abs/2412.08655

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