The use of acoustic waves in researches related to sea water is of most importance among scientists recently. Since these waves are the only waves, transmitted in water with lowest attenuation and high speed, they can be used in many scientific fields. The main goal of this research is to better understand the physics and mechanisms of sound-seabed interaction, including acoustic penetration, p...

We review studies of the generation and propagation of nonlinear and shock sound waves in He II the superfluid phase of He , both under the saturated vapor pressure SVP and at elevated pressures. The evolution in shape of second and first sound waves excited by a pulsed heater has been investigated for increasing power W of the heat pulse. It has been found that, by increasing the pressure P fr...

Spherical microphone arrays are very well suited for sound field measurements in enclosures or interior spaces, and generally in acoustic environments where sound waves impinge on the array from multiple directions. Because of their directional properties, they make it possible to resolve sound waves traveling in any direction. In particular, rigid sphere microphone arrays are robust, and have ...

Experimental and theoretical studies of low-frequency, long-range sound propagation through a fluctuating ocean are important for many practical problems, e.g. source detection and ranging, communication, and acoustic tomography. The coherence of low-frequency sound waves propagating over megameter distances diminishes noticeably due to sound scattering by internal gravity waves. As a result, t...

We propose a new method to recognize gestures from sound waves. The main contribution of this paper is to recognize gestures based on the analysis of short-time Fourier transforms (STFT) using the Doppler effect to sense gestures. To do this, we generate an inaudible tone, which gets frequency-shifted when it reflects off moving objects like the hand. We measure this shift with the microphone t...

Low-lying collective excitations in even-even vibrational and transitional nuclei may be described semiclassically as quadrupole running waves on the surface of the nucleus ("tidal waves"), and the observed vibrational-rotational behavior can be thought of as resulting from a rotating condensate of interacting d bosons. These concepts have been investigated by measuring lifetimes of the levels ...

Shock waves are defined as types of acoustic pressure waves that develop during sudden releases of energy. The best-known natural phenomenon is thunder following lightning. Another example is the “bang” an aircraft produces when it breaks the sound barrier. Both focused shock waves and unfocused sound waves are produced in these examples. Additionally, almost all other forms of energy are relea...

A parabolic dish microphone is like a mirror telescope for sound. A parabolic reflector is used to collect and focus sound waves to a microphone receiver [1, 2]. The parabolic shape has the property that all sound waves impinging parallel to the central axis of the dish are reflected to its focus point. When the dish is aimed at a distant sound source it is safe to assume that all the sound wav...