This article investigates the scattering characteristics of Lamb waves from a debonding at a structural feature in a composite laminate. This study specifically focuses on the use of the low frequency fundamental antisymmetric (A(0)) Lamb wave as the incident wave for debonding detection. Three-dimensional finite element (FE) simulations and experimental measurements are used to investigate the...

The Parabolic Equation Method ( P E M ) is the commonly used method to deal with wave propagation in random media. This method basically requires the small ratio of wave length to correlation length (small angle scattering). Recently, de Wolf/2/ and Rino/3/ extended the PEM by including the backscattered wave, retaining the small angle scattering. In his dissertation, GroBe/4/ generalized the P...

The wave propagation in a one-dimensional nonhomogeneous medium is considered, where the wave speed and the restoring force depend on location. In the frequency domain this is equivalent to the Schrijdinger equation d2$/dx2 + k211, = k2P(x)II, + Q(x)Jt with an added potential proportional to energy. The scattering and bound-state solutions of this equation are studied and the properties of the ...

In this paper, we use a straightforward numerical method to solve scattering models in one-dimensional lattices based on tight-binding band structure. We do by using the wave packet approach scattering, which presents more intuitive physical picture than traditional plane approach. Moreover, general matrix diagonalization that is easily accessible undergraduate students taking first course quan...

1.Introduction The wave scattering from rough surfaces is an important problem which closely relates to the measurement technology or diagnosing techniques by using microwave, millimeter wave, light wave or acoustic wave (1). Various kinds of theoretical models and methods for analyzing the wave scattering from random rough surfaces have been proposed so far. However, they have often used appro...

The scattering problem under the influence of the Aharonov-Bohm (AB) potential is reconsidered. By solving the Lippmann-Schwinger (LS) equation we obtain the wave function of the scattering state in this system. In spite of working with a plane wave as an incident wave we obtain the same wave function as was given by Aharonov and Bohm. Another method to solve the scattering problem is given by ...

The matrix variational Padé approximant and its generalization to elastic wave scattering are discussed. Predictions of the method for the scattering of a longitudinal plane wave are compared with the exact scattering from spherical voids and inclusions. Its predictions are also compared to those of the first and second Born approximations and to the standard matrix Padé approximant based on th...

We apply a semiclassical approach to the scattering problem of a vibrational wave packet in the vicinity of a conical intersection of electronic energy surfaces and derive analytical expressions for the scattering matrix. The latter are valid when the scattering length that scales as square root(h) is small and a wave packet passes through the scattering region with a constant velocity. The ana...

Scattering of ambient radiation into receivers by secondary mirror supports can potentially degrade performance of radiotelescopes. A geometry for the support struts with slanted planar faces to keep scattering sidelobes close to the antenna pointing direction is analyzed. Scattering of the plane wave is within ~15o of boresight, while the spherical wave scattering is within ~1o of boresight. ...

Underground rocks usually have complex pore system with a variety of pore types and a wide range of pore size. The effects of pore structure on elastic wave attenuation cannot be neglected. We investigated the pore structure effects on P-wave scattering attenuation in dry rocks by pore-scale modeling based on the wave theory and the similarity principle. Our modeling results indicate that pore ...