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Shear wave velocity measurement of upper trapezius muscle by color Doppler shear wave imaging
Journal of Medical Ultrasonics, 2017Skeletal muscle stiffness is thought to be the result of increased tissue hardness, but measurement accuracy has been dependent on operator technique. We have proposed a novel shear wave real-time imaging method (color Doppler shear wave imaging: CD SWI) with continuous shear waves excited from the tissue surface by a mechanical vibrator.Using the ...
Atsushi, Yamamoto +9 more
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Means for obtaining shear wave velocities
The Journal of the Acoustical Society of America, 1989The present invention provides a method of logging a subterranean formation through a wellbore containing a fluid, wherein no shear wave signal is obtainable utilizing conventional sonic well logging tools suspended in the wellbore. The shear wave signal is not obtainable usually because the acoustic velocity of the wellbore fluid is greater than the ...
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Shear-wave velocity measurement of soils using Rayleigh waves
Canadian Geotechnical Journal, 1992A modified version of the spectral analysis of surface waves (SASW) equipment and analysis procedure has been developed to determine in situ shear-wave velocity variation with depth from the ground surface. A microcomputer has been programmed to acquire waveform data and perform the relevant spectral analyses that were previously done by signal ...
K. O. Addo, P. K. Robertson
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Reservoir description using shear-wave velocities
EAGE/SEG Research Workshop 1990, 1990The vector analysis of shear-waves provides an opportunity to improve upon existing seismic methods for imaging the subsurface, to include a detailed investigation of the internal structure of reservoir rock and patterns of flow behaviour.
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On linear wave motions in magnetic-velocity shears
Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1977The propagation properties of linear wave motions in magnetic and/or velocity shears which vary in one coordinate z (say) are usually governed by a second order linear ordinary differential equation in the independent variable z. It is proved that associated with any such differential equation there always exists a quantity A which is independent of z.
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Using refracted shear waves for velocity estimation
Geophysical Prospecting, 2001The most difficult part of multicomponent processing is the estimation of the shear‐wave velocity map for migration. We used refracted shear waves and a simple iterative method called wavefield continuation (WFC) to evaluate the shallow shear‐wave velocity profile on a real data example.
L. Pautet, W.A. Kuperman, L. Dorman
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Shear wave velocities in the Earth's mantle
Physics of the Earth and Planetary Interiors, 1972Direct measurement of the travel time gradient for S waves together with travel time data are used to derive a shear velocity model for the earth's mantle. In order to satisfy the data it is necessary to discard the usual assumption of lateral homogeneity below shallow depths.
Russell Robinson, Robert L. Kovach
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Shear wave velocity profiles of fill dams
Soil Dynamics and Earthquake Engineering, 2018Abstract The shear stiffness (Gmax), which is determined from the shear wave velocity (Vs), is an essential parameter in dynamic analyses of fill dams. In this study, Vs profiles were collected and interpreted after comprehensive in situ geophysical seismic surveys of 28 fill dams.
DongSoon Park, Tadahiro Kishida
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Liquefaction susceptibility and shear wave velocity
2005The influence of age and soil type on Cyclic Resistance Ratio (CRR) and normalized small strain shear wave velocity has been examined here using cyclic laboratory tests on frozen and high-quality undisturbed specimens of Pleistocene and Holocene non-cohesive soils comprised of silt to pebble size particles and in-situ shear wave velocity measurements ...
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Sediment shear-wave velocities derived from Stonely wave observations
The Journal of the Acoustical Society of America, 1980As part of a series of acoustic measurements conducted off the coast of Jacksonville, Florida in 1976, experiments were performed to determine sediment shear-wave velocities. Explosive charges were used to excite Stonely waves which were detected by an ocean-bottom seismograph at ranges of 0.5 to 1.5 km. The shear velocity as a function of depth in the
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