shear-wave velocity ( ) is an important parameter used for site characterization in geotechnical engineering. however, dispersion curve inversion is challenging for most inversion methods due to its high non-linearity and mix-determined trait. in order to overcome these problems, in this study, a joint inversion strategy is proposed based on the particle swarm optimization (pso) algorithm. the ...

The two-dimensional sloshing problem is considered in a half-plane covered by a rigid dock with two symmetric gaps. It is proved that the antisymmetric (symmetric) sloshing eigenvalues are monotonically decreasing (increasing) functions of spacing between gaps and formulae for their derivatives are obtained. sloshing problem / eigenvalue / eigenfunction / integral operator / asymptotic formula ...

Sloshing refers to the free surface motion of a fluid in a container. We study the linearized sloshing problem of an incompressible, inviscid, irrotational fluid in a container, where we focus on the regime where the effect of surface tension dominates the effect of gravity. This is especially important in the microgravity environment, where scientists and engineers have worked to improve our u...

A novel PDE solver using the multidimensional wave digital filtering (MDWDF) technique to achieve the solution of a 2D seismic wave system is presented. In essence, the continuous physical system served by a linear Kirchhoff circuit is transformed to an equivalent discrete dynamic system implemented by a MD wave digital filtering (MDWDF) circuit. This amounts to numerically approximating the di...

Using array analysis, the direction and distance to a seismic P wave source can be determined. However, individual arrays are limited in their geographical coverage and by their resolving capability, which is determined by the array aperture, configuration, and number of stations. We demonstrate these limitations on three large seismic arrays located in Japan, Europe, and California, and find t...

Attenuation in seismic wave propagation is a common cause for poor illumination of subsurface structures. Attempts to compensate for amplitude loss in seismic images by amplifying the wavefield may boost high-frequency components and create undesirable imaging artifacts. In this paper, rather than amplifying the wavefield directly, we develop a stable compensation operator using smooth division...

S U M M A R Y Seismic tomography has been one of the primary tools to image the interior of the earth and other elastic structures. To date the inversions of compressional (P) and shear (S) wave speeds have been carried out separately under the assumption that P traveltimes are affected only by the P wave speed of the elastic media and S traveltimes by the S wave speed. Using numerical and anal...

the goal of this laboratory study is to investigate the effect of pore shapes on seismic wave velocities in carbonate rocks under reservoir conditions. in this research, 41 core plugs of carbonate rocks from oil fields of the southwest of iran were prepared. the compressional and shear wave velocities were measured in both dry and brine saturated samples under several pressures especially reser...

Seismic-wave Attenuation and the state

First arrivals of seismic waves were recorded along the Kamchatka arc using broadband seismic stations deployed for one year in 1998–1999. Cross correlation methods were used from a high resolution data set for tomographic inversion of body waves. The P-wave teleseismic tomography shows evidence of slab shoaling along the northern terminus of the Kamchatka subduction zone. Tomographic anomalies...