A combination of borehole Stoneley waves from full waveform acoustic logs and direct shear wave logs was used to estimate formation permeability and shear wave velocity. Data sets used here were collected by ARea's array full waveform acoustic logging tool and shear wave logging tool. The Pand S-wave velocities of the formation are determined by threshold detection with cross-correlation correc...

Locating the trajectory of an incoming projectile has important military and civilian applications. The origin of the trajectory can be used to locate sniper fire, and the end-point can be used to determine target hit coordinates on appropriately instrumented target ranges used by armed forces as well as civilian agencies (police and sports). Such non-contact determination of hit coordinates ca...

We demonstrate heterodyne mixing of a 94 GHz millimetre wave photonic signal, supplied by a Gunn diode oscillator, with coherent acoustic waves of frequency ~100 GHz, generated by pulsed laser excitation of a semiconductor surface. The mixing takes place in a millimetre wave Schottky diode, and the intermediate frequency electrical signal is in the 1-12 GHz range. The mixing process preserves a...

This paper studies the propagation of shear waves in a composite structure consisting of a piezoelectric layer perfectly bonded over a micropolar elastic half space. The general dispersion equations for the existence of shear waves are obtained analytically in the closed form. Some particular cases have been discussed and in one special case the relation obtained is in agreement with existing r...

The propagation of arbitrary amplitude dust ion acoustic waves (DIAWs) in a magnetized collisional dusty plasma including hot electrons, with kappa velocity distribution for electrons, warm ions and dust particles has been studied. In the presence of immobile massive dust particulates, DIAWs have been investigated through the Sagdeev pseudo-potential method. It is demonstrated that the amplitud...

The interaction of an acoustic wave with two joined flat plates results in a diffracted acoustic wave emanating from the junction. The plates are assumed, for simplicity, to have different masses but no stiffness, and the exact solution of the two-dimensional diffraction problem is derived as a Fourier integral. The diffraction coefficient for a plane acoustic wave is found to depend in a simpl...

Amorphous titanium dioxide (TiO2) and gold (Au) doped TiO2-based surface acoustic wave (SAW) sensors have been investigated as hydrogen gas detectors. The nanocrystal-doped TiO2 films were synthesized through a sol-gel route, mixing a Ti-butoxide-based solution with diluted colloidal gold nanoparticles. The films were deposited via spin coating onto 64◦ YX LiNbO3 SAW transducers in a helium atm...

The most commonly used prediction techniques to study the steady state behaviour of coupled acousticporoelastic problems are based on the Finite Element Method. However, due to the large computational load when frequency increases, these methods are restricted to low frequency problems. Recently, a Wave Based Method was developed to tackle this type of problems in a more efficient way. The meth...

In this work, we derive a result of exact controllability for a structural acoustic partial differential equation (PDE) model, comprised of a three-dimensional interior acoustic wave equation coupled to a two-dimensional Kirchoff plate equation, with the coupling being accomplished across a boundary interface. For this PDE system, we show that by means of boundary controls, the interior wave an...

Acoustic-fluid interactions not only has had a long history but has recently experienced renewed scrutiny because of their vast potential for microscale fluid and particle manipulation. Here we unravel a fascinating and anomalous ensemble of dynamic 'acoustowetting' phenomena in which a thin film drawn from a sessile drop first spreads in opposition to the acoustic wave propagation direction. T...