We have developed a technique in ultrasonic correlation spectroscopy called diffusing acoustic wave spectroscopy (DAWS). In this technique, the motion of the scatterers (e.g., particles or inclusions) is determined from the temporal fluctuations of multiply scattered sound. In DAWS, the propagation of multiply scattered sound is described using the diffusion approximation, which allows the auto...

AR = cavity aspect ratio a = speed of sound b = cavity half-width ~ C = dynamic compressibility c = phase speed cp = specific heat at constant pressure f = frequency H = cavity depth k = wave number m = propagation constant P = pressure Pr = Prandtl number R = reflection coefficient p = acoustic pressure pi = initial pulse amplitude Re = acoustic Reynolds number s = cavity spacing T = temperatu...

Scientific objective of this research is to understand acoustic wave propagation in a dynamic environment in two different frequency bands: (a) Low frequency band (50 Hz to 500 Hz). The subject of interest in this band is to assess the effect of environment anisotropy on acoustic wave propagation, with an emphasis on the separation of different effects due to horizontal refraction and mode coup...

Non-invasive methods for liver stiffness assessment have been introduced over recent years. Of these, two main methods for estimating liver fibrosis using ultrasound elastography have become established in clinical practice: shear wave elastography and quasi-static or strain elastography. Shear waves are waves with a motion perpendicular (lateral) to the direction of the generating force. Shear...

from the early 1950s, estimating the autocorrelations of polynomials with coefficients on the unit circle has found applications in ising spin systems and in surface acoustic wave designs. in this paper, a technique is introduced that not only estimates the autocorrelations, but for some special types of such polynomials, it locates the frequencies at which maximum autocorrelation occurs.

In-situ planetary sample analysis is a major goal in current and future NASA exploration missions. In general in-situ analysis experiments are designed to investigate chemical, biological or geological markers or properties to determine the complex history of the body being studied or for use as a pre-screening measurement to increase the scientific value of samples selected for sample return. ...

Microsensor technology is the most advanced area in the eld of microsystem technology. However, due to the typically low signal-to-noise ratios of these microsensors it is necessary to employ statistical methods for the data analysis of these systems. Taking a surface acoustic wave sensor array as an example two applications of statistical data analysis in this eld are presented. First, it is s...

This study aimed to replace the current discontinuous rail monitoring system by applying “Plug and Play” technology to rail system monitoring to enable real-time monitoring, and by confirming on-condition maintenance efficiency and reliability. It examined a wireless sensor monitoring system which uses SAW (Surface Acoustic Wave) technology to monitor temperature changes in the axle box bearing...

nothing so small as to escape our inquiry; hence there is a new visible World discovered to the understanding.” Thus wrote Robert Hooke in his pioneering work Micrographia [1] published by the Royal Society in 1664. In this revolutionary book, Hooke described with excitement his discoveries using a simple light microscope, coining the word ‘cell’ to define the microscopic structures he saw in c...

The diagnosis of infectious diseases in the Developing World is technologically challenging requiring complex biological assays with a high analytical performance, at minimal cost. By using an opto-acoustic immunoassay technology, integrating components commonly used in mobile phone technologies, including surface acoustic wave (SAW) transducers to provide pressure driven flow and a CMOS camera...