The new age of fibrous and porous-based composite materials has excellent acoustic
characteristics. Some of the prominent areas where these acoustical materials have found …

In this review paper, we examine some of the recent advances in the parametric acoustic
array (PAA) since it was first applied in air in 1983 by Yoneyama. These advances include …

Interconnected pore cell in appropriately chosen porous media can help to enhance their
sound absorption performance. Acoustic absorbing foam materials were produced from …

This paper presents a review of the literature on the subject of in situ acoustic impedance
measurement techniques. The review is intended to be as extensive enough, so that the …

In this study, an elastomeric nanocomposite foam was fabricated on the basis of ethylene-
propylene-diene-monomer (EPDM) rubber filled with multi-walled carbon nanotubes …

The near and far fields of traditional loudspeakers are differentiated by whether the sound
pressure amplitude is inversely proportional to the propagating distance. However, the …

The existing non-paraxial expression of audio sounds generated by a parametric array
loudspeaker (pal) is hard to calculate due to the fivefold integral in it. A rigorous solution of …

The far field directivity is a straightforward indicator to describe the radiation pattern of the
audio sound generated by a parametric array loudspeaker (pal), but its accurate and …

This paper proposes a new macroscopic model for sound-absorbing poroelastic media
which is derived by using the homogenization theory based on the method of asymptotic …

Parametric loudspeaker arrays comprise arrangements of piezoelectric ultrasonic
transducers that emit highly directive audible sound, thanks to the nonlinear parametric …