This paper reports preliminary environmental inversion results of acoustic data collected simultaneously at two receiving systems during the RADAR’07 sea trial. These receiving systems have communication capabilities that allow for transfering acoustic and telemetric data to a base station with processing capabilities in order to produce environmental estimates during the acoustic experiment. D...

A multilayer encapsulated coating has been developed for underwater acoustic attenuation purposes. This coating provides an option for electronically activating encapsulated piezoelectric devices to increase the coatings passvie sound attenuation performance through active control methods. These methods include the ability to sense the incident and reflected acoustic pressure field and produce ...

Ultrafast laser pulses are used to generate single-cycle picosecond acoustic pulses in thin metal films on silicon. For small initial excitation spot sizes, propagation of the acoustic pulses across a 485-mm Si crystal leads to significant diffraction effects. The temporal reshaping of the acoustic wave form due to diffraction is investigated, and we demonstrate that the acoustic far field can ...

Mechanical phenotyping of single cells is an emerging tool for cell classification, enabling assessment of effective parameters relating to cells' interior molecular content and structure. Here, we present iso-acoustic focusing, an equilibrium method to analyze the effective acoustic impedance of single cells in continuous flow. While flowing through a microchannel, cells migrate sideways, infl...

In this study we model the sound attenuation properties of a hearing aid earmold tube. The model includes thermoviscous acoustic effects and it couples structural vibrations to the external acoustic field. Moreover, the finite element domain is coupled at two boundaries with an electroacoustic model of a hearing aid and an acoustic 2-cc coupler.

Combustion noise analyses in a hybrid computational aeroacoustics (CAA) context are presented. Acoustic perturbation equations for reacting flows (APE-RF) describe the wave propagation, while unsteady results from a variable density incompressible reactive large-eddy simulation (LES) are used to evaluate the acoustic source terms. To simulate combustion generated noise via such a hybrid approac...

not more than 200 words) An interesting possibility for improved surveillance capabilities in challenging underwater environments and against targets with low acoustic signatures is the use of multisensor systems combined with dataor information fusion. This work describes how data fusion can be used for tracking and classifying targets using passive underwater acoustic and electric field senso...

We investigate the effect of a strong large scale magnetic field on the reflection of high frequency acoustic modes in rapidly oscillating Ap stars. To that end we consider a toy model composed of an isothermal atmosphere matched onto a polytropic interior and determine the numerical solution to the set of ideal magneto-hydrodynamic equations in a local plane-parallel approximation with constan...

Many conventional security systems use visual information from a video camera. However, these systems may not be able to acquire the important scenes in the blind area of the video camera. Acoustic security systems can support conventional visual security systems with acoustic events detection. In our research, we focused on acoustic security systems in the near field, and we designed a prototy...