Pseudo-projection approach to reconstruct locations of point-like scatterers characterized by Lame parameters and mass densities in an elastic half-space

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:169

Article

Touhei, Terumi¹  Maruyama, Taizo¹ 

[1] Tokyo Univ Sci, Dept Civil Engn, 2641 Yamazaki, Noda, Chiba 2788510, Japan

关键词: Inverse scattering;    Elastic half-space;    MUSIC algorithm;    Near-field observation;    Far-field properties of Green's functions;    Monopole and dipole sources;    Pseudo-projections;   

DOI  :  10.1016/j.ijsolstr.2019.04.019

来源: Elsevier

【 摘 要 】

A method for reconstructing the locations of point-like scatterers in an elastic half-space is developed in this article. Point-like scatterers are characterized by fluctuations of the Lame parameters and the mass densities from the background structure of the wavefield. A representation of the wavefield is realized with the monopole and dipole Green's functions. The main contribution of the present work is to clarify the far-field properties of the Green's functions for both the monopole and dipole sources, which yields the pseudo-projection approach to the wave problem. Indicator functions that reconstruct the locations of point-like scatterers are defined by the far-field operator derived from the pseudo-projections and the near-field observation. Numerical computations were carried out to verify the accuracy of the pseudo projection method. The sensitivities of the accuracy of the reconstruction results for the proposed method to random noise, the grid resolution at the free surface, and the analyzed frequency were also examined. (C) 2019 Elsevier Ltd. All rights reserved.

【 授权许可】

Free