日本語フィールド
著者：Haruka Ishibashi, Kenbu Teramoto題名：Dynamic shear strain analysis for reconstructing divergence of the phase velocity vector field発表情報：Proceedings of the SICE Annual Conference 2018 ページ: 1332-1337キーワード：概要：抄録：The dynamic shear strain analysis is developed to detect the evanescent wave field which is scattered by a finite defect in a plate. In this paper, the problem of reconstructing a super-resolved image of defects in the thin-plate-like structures over A0-mode Lamb-wave field is considered. The physical principles of the dynamic shear strain analysis is summarized as follows: (1) when the single propagating wave front exists on the surface of the object without defects or boundaries, the orthogonal pair of the out-of-plane shear strains are linearly dependent each other under the advection equation. Such that, the divergence of the phase velocity vector field becomes zero. Therefore the determinant of a covariance matrix, which is composed of the orthogonal pair of the shear strains, becomes zero, (2)when a region of interest having somewhat inhomogeneity exists, scattered wave arises in the Lamb-wave field. Thus the phase velocity vector field in that region has a positive value. Consequently, the determinant becomes larger than zero in the near field of the defects or boundaries. In this study, the computational process in wave field near the defect is discussed and their physical meanings are investigated through numerical experiments.英語フィールド
Author：Haruka Ishibashi, Kenbu TeramotoTitle：Dynamic shear strain analysis for reconstructing divergence of the phase velocity vector fieldAnnouncement information:Proceedings of the SICE Annual Conference 2018 Page: 1332-1337An abstract：The dynamic shear strain analysis is developed to detect the evanescent wave field which is scattered by a finite defect in a plate. In this paper, the problem of reconstructing a super-resolved image of defects in the thin-plate-like structures over A0-mode Lamb-wave field is considered. The physical principles of the dynamic shear strain analysis is summarized as follows: (1) when the single propagating wave front exists on the surface of the object without defects or boundaries, the orthogonal pair of the out-of-plane shear strains are linearly dependent each other under the advection equation. Such that, the divergence of the phase velocity vector field becomes zero. Therefore the determinant of a covariance matrix, which is composed of the orthogonal pair of the shear strains, becomes zero, (2)when a region of interest having somewhat inhomogeneity exists, scattered wave arises in the Lamb-wave field. Thus the phase velocity vector field in that region has a positive value. Consequently, the determinant becomes larger than zero in the near field of the defects or boundaries. In this study, the computational process in wave field near the defect is discussed and their physical meanings are investigated through numerical experiments.