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arXiv · 2209.07006

Time- vs. frequency- domain inverse elastic scattering: Theory and experiment

Xiaoli Liu·Jian Song·Fatemeh Pourahmadian·Houssem Haddar
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Abstract

This study formally adapts the time-domain linear sampling method (TLSM) for ultrasonic imaging of stationary and evolving fractures in safety-critical components. The TLSM indicator is then applied to the laboratory test data of [22, 18] and the obtained reconstructions are compared to their frequency-domain counterparts. The results highlight the unique capability of the time-domain imaging functional for high-fidelity tracking of evolving damage, and its relative robustness to sparse and reduced aperture data at moderate noise levels. A comparative analysis of the TLSM images against the multifrequency LSM maps of [22] further reveals that thanks to the full-waveform inversion in time and space, the TLSM generates images of remarkably higher quality with the same dataset.

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Xiaoli Liu, Jian Song, Fatemeh Pourahmadian, Houssem Haddar. 2022-09-15. Time- vs. frequency- domain inverse elastic scattering: Theory and experiment. https://arxiv.org/abs/2209.07006

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