Introduction Compared to ultrasonic bulk waves that travel in infinite media with no boundary influence, guided waves require a structural boundary for propagation. As an example, some guided wave possibilities are illustrated in Figure 1 for a Rayleigh surface wave, a Lamb wave, and a Stonely wave at an interface between two materials.

Abstract—One good analysis method in seismic response analysis is direct time integration, which widely adopts Rayleigh damping. An approach is presented for selection of Rayleigh damping coefficients to be used in seismic analyses to produce a response that is consistent with Modal damping response. In the presented approach, the expression of the error of peak response, acquired through compl...

The conditions that strain energy tensor and necessary condition on the roots of a constitutive equation must be positive definite produces some inequalities. These inequalities reduce the number of Rayleigh waves in orthotropic and transversely isotropic materials. Some earlier published work is found to be erroneous.

A combined analytical, numerical, and experimental study of the traveling-wave wall mode in rotating Rayleigh-Bénard convection is presented. No-slip top and bottom boundary conditions are used for the numerical computation of the linear stability, and the coefficients of the linear complex Ginzburg-Landau equation are then computed for various rotation rates. Numerical results for the no-slip ...

AbstractIn the present paper the problem of propagation of Rayleigh waves due to a finite rigid barrier in a shallow ocean has been analyzed. The reflected, transmitted and scattered waves have been obtained by fourier transformation and Wiener-Hopf technique. Numerical computations for the amplitude of the scattered and the reflected waves have been made versus the wave number. It has been don...

The theory of creeping waves is developed by applying the Sommerfeld-Watson transformation on the normal-mode solution for acoustic scattering from an infinite elastic cylinder. Two types of radiating, circumferential waves emerge: (1) highly attenuated “Franz-type” waves with subsonic speeds, and (2) supersonic “Rayleigh-type” waves which are only slightly attenuated. The experimental study of...

in this paper we are going to show the importance of mode identification in microtremor array analysis. the idea come from four concentric ambient noise array recordings with aperture 100 to 1000 meters, performed in southern urban area of tehran near the shrine of imam khomeini. these measurements were part of a comprehensive research project with the aim of determination of deep shear wave ve...

Long-period (100-330 s) fundamental-mode Love and Rayleigh waves have been processed to measure the great circle phase velocities for about 200 and 250 paths, respectively. The observations are inverted for regionalized phase velocities and for an even-order harmonic expansion of the lateral velocity heterogeneity. The regionalized inversions achieve a maximum variance reduction of about 65% an...

The problem of an electromagnetic wave scattered by a slab with two rough boundaries is solved by the small-perturbation method under the Rayleigh hypothesis. To obtain the perturbative development, we use a systematic procedure that involves integral equations called the reduced Rayleigh equations. Then we show for a dielectric slab deposited on a silver film that the backscattering enhancemen...