A matching pursuit method based on training an over-complete dictionary is investigated.By using the K-singular value decomposition(K-SVD)algorithm,an over-complete dictionary that describes the Lamb wave signals is t...A matching pursuit method based on training an over-complete dictionary is investigated.By using the K-singular value decomposition(K-SVD)algorithm,an over-complete dictionary that describes the Lamb wave signals is trained.The results demonstrate that the method can effectively remove redundant information and separate multiple Lamb wave modes.The matching pursuit method with the K-SVD algorithm shows its efficiency for Lamb wave signal processing.展开更多
An analytical model of Lamb wave scattering from a circular blind hole in isotropic plates is presented using the Mindlin plate theory for describing in-plane and flexural wave modes simultaneously. The model makes us...An analytical model of Lamb wave scattering from a circular blind hole in isotropic plates is presented using the Mindlin plate theory for describing in-plane and flexural wave modes simultaneously. The model makes use of the wave function expansion technique and the boundary conditions at the hole edge to evaluate the scattered far fields of three fundamental guided wave modes. Comparisons are made to existing approximate models using Poisson/Kirchhoff theory and Poisson/Mindlin theory and a 3D model using the exact 3D equations. The results reveal that the present model is more consistent with the exact 3D model at higher frequencies than existing approximate models.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11074164,11274226,11074273,61171145the Innovation Foundation of Shanghai Municipal Commission of Education(No 11YZ17)the Ph.D.Foundation of Ministry of Education of China(20103108120011)。
文摘A matching pursuit method based on training an over-complete dictionary is investigated.By using the K-singular value decomposition(K-SVD)algorithm,an over-complete dictionary that describes the Lamb wave signals is trained.The results demonstrate that the method can effectively remove redundant information and separate multiple Lamb wave modes.The matching pursuit method with the K-SVD algorithm shows its efficiency for Lamb wave signal processing.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274226, 11074164 and 61171145.
文摘An analytical model of Lamb wave scattering from a circular blind hole in isotropic plates is presented using the Mindlin plate theory for describing in-plane and flexural wave modes simultaneously. The model makes use of the wave function expansion technique and the boundary conditions at the hole edge to evaluate the scattered far fields of three fundamental guided wave modes. Comparisons are made to existing approximate models using Poisson/Kirchhoff theory and Poisson/Mindlin theory and a 3D model using the exact 3D equations. The results reveal that the present model is more consistent with the exact 3D model at higher frequencies than existing approximate models.