English
Related papers

Related papers: Time Reversal for elastic scatterer location from …

200 papers

This paper is concerned with the problem of scattering of time-harmonic acoustic waves from an impenetrable obstacle in a piecewise homogeneous medium. The well-posedness of the direct problem is established, employing the integral equation…

Analysis of PDEs · Mathematics 2009-12-09 xiaodong Liu , Bo Zhang

This paper is concerned with time reversal in \emph{photoacoustic tomography} (PAT) of dissipative media that are similar to water. Under an appropriate condition, it is shown that the time reversal method in \cite{Wa11,AmBrGaWa11} based on…

Analysis of PDEs · Mathematics 2013-08-05 Richard Kowar

An inverse scattering problem for the 3D acoustic equation in time domain is considered. The unknown spatially distributed speed of sound is the subject of the solution of this problem. A single location of the point source is used. Using a…

Mathematical Physics · Physics 2019-01-01 Michael V. Klibanov , Jingzhi Li , Wenlong Zhang

This paper is concerned with the inverse scattering problem involving the time-domain elastic wave equations in a bounded $d$-dimensional domain. First, an explicit reconstruction formula for the density is established by means of the…

Analysis of PDEs · Mathematics 2023-01-20 Bochao Chen , Yixian Gao , Shuguan Ji , Yang Liu

In this article we study the inverse problem of thermoacoustic tomography (TAT) on a medium with attenuation represented by a time- convolution (or memory) term, and whose consideration is motivated by the modeling of ultrasound waves in…

Analysis of PDEs · Mathematics 2017-03-29 Sebastian Acosta , Benjamin Palacios

The goal of this work is to recover articulatory information from the speech signal by acoustic-to-articulatory inversion. One of the main difficulties with inversion is that the problem is underdetermined and inversion methods generally…

Computation and Language · Computer Science 2007-05-23 Blaise Potard , Yves Laprie

This paper is concerned with the problem of inverse scattering of time-harmonic acoustic plane waves by a two-layered medium with a locally rough interface in 2D. A direct imaging method is proposed to reconstruct the locally rough…

Numerical Analysis · Mathematics 2023-05-11 Long Li , Jiansheng Yang , Bo Zhang , Haiwen Zhang

Reciprocity is one of the fundamental characteristics of wave propagation in linear time-invariant media with preserved time-reversal symmetry. Breaking reciprocity opens the way to numerous applications in the fields of phononics and…

Applied Physics · Physics 2024-09-09 Matthieu Malléjac , Romain Fleury

Space-time materials are obtained by modulating a physical medium with a traveling-wave perturbation of one or several of its constitutive parameters, such as the density or the bulk modulus in the case of acoustic materials. When this…

Materials Science · Physics 2026-02-10 J. Galiana , J. Redondo , R. Picó , V. J. Sánchez-Morcillo

We consider the resolution of the single frequency reverse time migration (RTM) method for extended targets without the assumption of the validation of geometric optics approximation. The resolution analysis, which applies in both…

Mathematical Physics · Physics 2014-06-11 Junqing Chen , Zhiming Chen , Guanghui Huang

An inversion method for time-resolved data from ultrafast experiments is introduced, based on forward-optimisation in a trajectory basis. The method is applied to experimental data from x-ray scattering of the photochemical ring-opening…

Chemical Physics · Physics 2024-10-28 Kyle Acheson , Adam Kirrander

Generalized impedance boundary conditions are effective, approximate boundary conditions that describe scattering of waves in situations where the wave interaction with the material involves multiple scales. In particular, this includes…

Numerical Analysis · Mathematics 2020-05-29 Lehel Banjai , Christian Lubich , Joerg Nick

This paper concerns the numerical simulation of time domain inverse acoustic scattering problems with a point-like scatterer, multiple point-like scatterers or normal size scatterers. Based on the Green's function and the application of the…

Numerical Analysis · Mathematics 2024-06-07 Qingqing Yu , Bo Chen , Jiaru Wang , Yao Sun

In this paper, we study time-harmonic electromagnetic scattering in two scenarios, where the anomalous scatterer is either a pair of electromagnetic sources or an inhomogeneous medium, both with compact supports. We are mainly concerned…

Analysis of PDEs · Mathematics 2022-04-07 Huaian Diao , Xiaoxu Fei , Hongyu Liu , Ke Yang

In this work, we are concerned with the inverse scattering by interfaces for the linearized and isotropic elastic model at a fixed frequency. First, we derive complex geometrical optic solutions with linear or spherical phases having a…

Analysis of PDEs · Mathematics 2013-11-19 Manas Kar , Mourad Sini

The motivation of this work is an inverse problem for the acoustic wave equation, where an array of sensors probes an unknown medium with pulses and measures the scattered waves. The goal of the inversion is to determine from these…

Numerical Analysis · Mathematics 2018-06-18 Liliana Borcea , Vladimir Druskin , Alexander V. Mamonov , Mikhail Zaslavsky

We propose in this paper a framework dedicated to the construction of what we call time elastic inner products that allows embedding sets of non-uniformly sampled multivariate time series of varying lengths into vector space structures.…

Discrete Mathematics · Computer Science 2011-02-15 Pierre-François Marteau

Attenuation of ultrasound waves varies with tissue composition, hence its estimation offers great potential for tissue characterization and diagnosis and staging of pathology. We recently proposed a method that allows to spatially…

Medical Physics · Physics 2020-10-13 Richard Rau , Ozan Unal , Dieter Schweizer , Valery Vishnevskiy , Orcun Goksel

When a signal is emitted from a source, recorded by an array of transducers, time reversed and re-emitted into the medium, it will refocus approximately on the source location. We analyze the refocusing resolution in a high frequency,…

Disordered Systems and Neural Networks · Physics 2007-05-23 George Papanicolaou , Leonid Ryzhik , Knut Solna

In this paper, we are concerned with the inverse electromagnetic scattering problem of recovering a complex scatterer by the corresponding electric far-field data. The complex scatterer consists of an inhomogeneous medium and a possibly…

Analysis of PDEs · Mathematics 2018-01-09 Youjun Deng , Hongyu Liu , Xiaodong Liu