日本語フィールド
著者：寺本 顕武, 井上 亮二 読み: テラモトケンブ イノウエリョウジ題名：A0モードラム波を用いた動的せん断歪み解析に基づく欠損部の近接場の撮像発表情報：計測自動制御学会論文集 巻: 47 号: 10 ページ: 422-429キーワード：ラム波, 非破壊検査, 動的せん断歪み解析法, 時空間勾配解析, 音響信号処理概要：The proposed imaging method utilizes the determinant of the dynamic shear strains covariance matrix
which are defined over the object surface. The determinant denotes the distribution of
correlated intensity modulation of the incident wave fronts with scattered ones. The value of the determinant, therefore, increases significantly in the near-field of the defects.
In this study, the computational process in the wave field near the defects
is discussed and their physical meanings are investigated through FDTD-simulations and acoustic experiments.抄録：Lamb waves have been used for
non-destructive inspection of thin-plate-like structures.
However, the conventional time-of-flight technique is not
reliable for locating the defects even in isotropic plates
because of the dispersiveness in the Lamb wave propagation.
Avoiding difficulties caused by the dispersiveness,
this paper proposes a novel dynamic shear strains analysis
which has an ability to localize defects with reconstructing
near-field images.
The proposed imaging method utilizes
the determinant of the dynamic shear strains covariance matrix
which are defined
over the object surface. The determinant denotes the distribution of
correlated intensity modulation
of the incident wave fronts with scattered ones. The value of the determinant,
therefore, increases
significantly in the near-field of the defects.
In this study, the computational process in the wave field near the defects
is discussed and their physical meanings are investigated
through FDTD-simulations and acoustic experiments.英語フィールド
Author：Kenbu Teramoto, Ryoji InoueTitle：Near-field Imaging of Defects Based on the Dynamic Shear Strain Analysis over the A0-mode Lamb Wave FieldAnnouncement information:Transaction of SICE Vol: 47 Issue: 10 Page: 422-429Keyword：Lamb wave, Non-destructive evaluation,
Dynamic shear strain analysis, Spatio-temporal gradient analysis,
Acoustical signal processingAn abstract：The proposed imaging method utilizes the determinant of the dynamic shear strains covariance matrix
which are defined over the object surface. The determinant denotes the distribution of
correlated intensity modulation of the incident wave fronts with scattered ones. The value of the determinant, therefore, increases significantly in the near-field of the defects.
In this study, the computational process in the wave field near the defects
is discussed and their physical meanings are investigated through FDTD-simulations and acoustic experiments.An abstract：Lamb waves have been used for
non-destructive inspection of thin-plate-like structures.
However, the conventional time-of-flight technique is not
reliable for locating the defects even in isotropic plates
because of the dispersiveness in the Lamb wave propagation.
Avoiding difficulties caused by the dispersiveness,
this paper proposes a novel dynamic shear strains analysis
which has an ability to localize defects with reconstructing
near-field images.
The proposed imaging method utilizes
the determinant of the dynamic shear strains covariance matrix
which are defined
over the object surface. The determinant denotes the distribution of
correlated intensity modulation
of the incident wave fronts with scattered ones. The value of the determinant,
therefore, increases
significantly in the near-field of the defects.
In this study, the computational process in the wave field near the defects
is discussed and their physical meanings are investigated
through FDTD-simulations and acoustic experiments.