by growing the population and need for settlement, many cities have been built on soft sediments and seismic areas. it emphasizes the need for a careful and reliable assessment of site effect phenomena. beyond the methods of studying site effects, microtremor recordings has become popular over the last decades as it offers a convenient, practical and low cost tool to be used in urbanized areas....

GABRIELS, P., SNIEDER, . and NOLET, G. 1987, In Situ Measurement of Shear-Wave Velocity in Sediments with Higher-Mode Rayleigh Waves, 35,187-196. A seismic survey was carried out on a tidal flat in the SW-Netherlands in order to determine shear-wave velocities in sediments by means of higher-mode Rayleigh waves. The dispersion properties of these Rayleigh waves were measured in the 2-D amplitud...

OBJECTIVE The purpose of this study is to determine if crawling wave elastography, a novel sonoelastography technique, can be used to provide quantitative measurements of thyroid tissue shear velocity (a measure of tissue stiffness) and distinguish between benign and malignant thyroid nodules. STUDY DESIGN Diagnostic test assessment. SETTING Academic university. SUBJECTS AND METHODS Fresh...

The liquefaction resistance of soil can be evaluated using laboratory tests such as cyclic simple shear, cyclic triaxial, cyclic torsional shear as well as field methods like Standard Penetration Test (SPT), Cone Penetration Test (CPT) and Shear Wave Velocity (Vs). In this regard, this study attempts to compare the results of the SPT based on the simplified procedure proposed by Seed and Idriss...

We extend the approach underlying the well-known Dix equation in reflection seismology to surface waves. Within the context of surface wave inversion, the Dix-type relation we derive for surface waves allows accurate depth profiles of shear-wave velocity to be constructed directly from phase velocity data, in contrast to perturbational methods. The depth profiles can subsequently be used as an ...

The goal of this study was to prospectively evaluate the diagnostic performance of Virtual Touch tissue imaging quantification (VTIQ) shear wave elastography in the discrimination of benign and malignant cervical lymph nodes in routine clinical practice. Shear wave velocity was analyzed using VTIQ in 100 patients with 100 histologically proven cervical lymph nodes. Diagnostic performance was ev...

[1] We calculated the elasticity of (Mg,Fe)SiO3-perovskite, using the plane-wave pseudopotential method for a pressure range that encompasses the earth’s lower mantle. Adding 25 mol% FeSiO3 to the Mg endmember decreases the shear modulus by 6% at zero pressure and by 8% at core mantle boundary pressures. The bulk modulus is less affected by iron, increasing by 2% at zero pressure and by 1% at t...

INTRODUCTION Peripheral nerves slide and stretch during limb movements. Changes in nerve stiffness associated with such movements have not been examined in detail but may be important in understanding movement-evoked pain in patients with a variety of different musculoskeletal conditions. METHODS Shear-wave elastography was used to examine stiffness in the median and tibial nerves of healthy ...

An approximate theory for the scattering of an incident plane P wave into tube waves in a fluid-filled borehole drilled through two homogeneous half-spaces is proposed in this paper. This theory is in excellent agreement with the zero frequency formulation (White, 1983) for frequencies below hundreds of Hertz (in the range of conventional crosshole or VSP experiments) and flnite difference simu...