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Westervelt's equation is a nonlinear wave equation that is widely used to model the propagation of sound waves in a compressible medium, with one important application being ultra-sound in human tissue. Two fundamental aspects of this…

Mathematical Physics · Physics 2023-06-14 Stephen C. Anco , Almudena P. Marquez , Tamara M. Garrido , Maria L. Gandarias

We propose a novel numerical homogenization method based on the edge multiscale approach for solving indefinite time-harmonic Maxwell equations in heterogeneous media with large wavenumber. Numerical methods for these equations in…

Numerical Analysis · Mathematics 2026-04-27 Yueqi Wang , Wing Tat Leung , Guanglian Li

In ultrasound imaging, propagation of an acoustic wavefront through heterogeneous media causes phase aberrations that degrade the coherence of the reflected wavefront, leading to reduced image resolution and contrast. Adaptive imaging…

In this paper we show local (and partially global) in time existence for the Westervelt equation with several versions of nonlinear damping. This enables us to prove well-posedness with spatially varying $L_\infty$-coefficients, which…

Analysis of PDEs · Mathematics 2015-09-25 Rainer Brunnhuber , Barbara Kaltenbacher , Petronela Radu

In this paper, we study the nonlinear periodic Westervelt equation with excitations located within a bounded domain in $\mathbb{R}^d$, where $d \in \{2,3\}$, subject to Robin boundary conditions. This problem is of particular interest for…

Analysis of PDEs · Mathematics 2026-01-06 Benjamin Rainer , Barbara Kaltenbacher

Optical response of free-electron gas leads to inherent nonlinear optical behaviour of nanostructured plasmonic materials enabled via both strong local field enhancements and inherent complex electron dynamics. We present a comprehensive…

In this paper we focus on high order finite element approximations of the electric field combined with suitable preconditioners, to solve the time-harmonic Maxwell's equations in waveguide configurations. The implementation of high order…

Numerical Analysis · Mathematics 2017-05-16 Marcella Bonazzoli , Victorita Dolean , Frédéric Hecht , Francesca Rapetti

In this paper we focus on high order finite element approximations of the electric field combined with suitable preconditioners, to solve the time-harmonic Maxwell's equations in waveguide configurations.The implementation of high order…

Numerical Analysis · Mathematics 2020-03-23 Marcella Bonazzoli , Victorita Dolean , Frédéric Hecht , Francesca Rapetti

This paper rigorously analyses preconditioners for the time-harmonic Maxwell equations with absorption, where the PDE is discretised using curl-conforming finite-element methods of fixed, arbitrary order and the preconditioner is…

Numerical Analysis · Mathematics 2020-03-23 Marcella Bonazzoli , Victorita Dolean , Ivan G. Graham , Euan A. Spence , Pierre-Henri Tournier

We investigate high-order harmonic generation in inhomogeneous media for reduced dimensionality models. We perform a phase-space analysis, in which we identify specific features caused by the field inhomogeneity. We compute high-order…

Atomic Physics · Physics 2016-05-25 C. Zagoya , M. Bonner , H. Chomet , E. Slade , C. Figueira de Morisson Faria

The attenuation of small-amplitude acoustic waves in a suspension containing ultrasound contrast agents (UCAs, coated microbubbles) is determined by the linear oscillation of the UCAs in the medium, which can be estimated via a linear…

Fluid Dynamics · Physics 2019-08-26 Lang Xia

Ultrasound contrast agents have been recently utilized in therapeutical implementations for targeted delivery of pharmaceutical substances. Radial pulsations of a cluster of encapsulated microbubbles under the action of an ultrasound field…

Fluid Dynamics · Physics 2018-11-19 S. Behniaa , M. Yahyavi , R. Habibpourbisafar , F. Mottaghi

Consider the scattering of a time-harmonic acoustic plane wave by a bounded elastic obstacle which is immersed in a homogeneous acoustic medium. This paper concerns an inverse acoustic-elastic interaction problem, which is to determine the…

Numerical Analysis · Mathematics 2020-04-22 Heping Dong , Jun Lai , Peijun Li

The oscillations of ultrasound contrast agents are of particular importance to the understanding of the propagation of acoustic waves in the bubbly liquids (suspensions of ultrasound contrast agents). Acoustic waves propagating in bubbly…

Fluid Dynamics · Physics 2018-10-05 Lang Xia

We present a finite volume method that is applicable to hyperbolic PDEs including spatially varying and semilinear nonconservative systems. The spatial discretization, like that of the well-known Clawpack software, is based on solving…

Numerical Analysis · Mathematics 2013-07-16 David I. Ketcheson , Matteo Parsani , Randall J. LeVeque

We analyze mathematically the acoustic imaging modality using bubbles as contrast agents. These bubbles are modeled by mass densities and bulk moduli enjoying contrasting scales. These contrasting scales allow them to resonate at certain…

Analysis of PDEs · Mathematics 2020-04-17 Alexander Dabrowski , Ahcene Ghandriche , Mourad Sini

Current state-of-the-art discrete optimization methods struggle behind when it comes to challenging contrast-enhancing discrete energies (i.e., favoring different labels for neighboring variables). This work suggests a multiscale approach…

Computer Vision and Pattern Recognition · Computer Science 2012-11-05 Shai Bagon , Meirav Galun

Accurate simulation of wave propagation in complex acoustic materials is crucial for applications in sound design, noise control, and material engineering. Traditional numerical solvers, such as finite element methods, are computationally…

Machine Learning · Computer Science 2025-10-14 Riccardo Fosco Gramaccioni , Christian Marinoni , Fabrizio Frezza , Aurelio Uncini , Danilo Comminiello

Accurate estimation of the Underwater acoustic (UWA) is a key part of underwater communications, especially for coherent systems. The severe multipath effects and large delay spreads make the estimation problem large-scale. The…

Signal Processing · Electrical Eng. & Systems 2023-08-25 Tian Tian , Agastya Raj , Bruno Missi Xavier , Ying Zhang , Feiyun Wu , Kunde Yang

Approximately 1.2% of the world's population has impaired voice production. As a result, automatic dysphonic voice detection has attracted considerable academic and clinical interest. However, existing methods for automated voice assessment…

Sound · Computer Science 2023-01-27 Jianwei Zhang , Julie Liss , Suren Jayasuriya , Visar Berisha