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Related papers: Thermoacoustic Tomography in Elastic Media

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Thermo-acoustic tomography is a non-invasive medical imaging technique, constituting a precise and cheap alternative to X-imaging. The principle is to excite a body to reconstruct with a pulse inducing an inhomogeneous heating and therefore…

Analysis of PDEs · Mathematics 2019-07-24 Maïtine Bergounioux , Elie Bretin , Yannick Privat

Dynamic optical coherence elastography (OCE) tracks mechanical wave propagation in the subsurface region of tissue to image its shear modulus. For bulk shear waves, the lateral resolution of the reconstructed modulus map (i.e.,…

Photoacoustic tomography (PAT) is a novel and promising technology in hybrid medical imaging that involves generating acoustic waves in the object of interest by stimulating electromagnetic energy. The acoustic wave is measured outside the…

Numerical Analysis · Mathematics 2022-08-24 Minam Moon , Injo Hur , Sunghwan Moon

We derive an explicit method for reconstructing singularities of the initial data in a thermoacoustic tomography problem, in the case of variable sound speed and limited boundary data. In order to obtain this explicit formula we assume the…

Analysis of PDEs · Mathematics 2009-05-19 Dustin Steinhauer

We recover the higher order terms for the acoustic wave equation from measurements of the modulus of the solution. The recovery of these coefficients is reduced to a question of stability for inverting a Hamiltonian flow transform, not the…

Analysis of PDEs · Mathematics 2016-07-14 Joonas Ilmavirta , Alden Waters

This paper is concerned with the mathematical analysis of time-dependent fluid-solid interaction problem associated with a bounded elastic body immersed in a homogeneous air or fluid above a local rough surface. We reformulate the unbounded…

Analysis of PDEs · Mathematics 2018-07-25 Changkun Wei , Jiaqing Yang

We consider the inverse problem of determining the initial states or the source term of a hyperbolic equation damped by some non-local time-fractional derivative. This framework is relevant to medical imaging such as thermoacoustic or…

Analysis of PDEs · Mathematics 2021-11-10 Xinchi Huang , Yavar Kian , Eric Soccorsi , Masahiro Yamamoto

In a medium where the dielectric permittivity is perturbed in the presence of an acoustic wave, optical scattering generates frequency-shifted light. In this paper we consider the inverse problem of recovering the optical properties of this…

Analysis of PDEs · Mathematics 2019-10-14 Francis J. Chung , Jeremy G. Hoskins , John C. Schotland

We consider time-harmonic elastodynamic problems in heterogeneous media.cWe focus on scattering problems in the high-frequency regime and incnearly incompressible media, where the the angular frequency $\omega$ and ratio of the Lam\'e…

Analysis of PDEs · Mathematics 2024-03-13 T. Chaumont-Frelet , S. Nicaise

We investigate an inverse source problem of the time-harmonic elastic wave equation. Some novel sampling-type numerical schemes are proposed to identify the moment tensor point sources in the Lam\'e system from near-field measurements.…

Numerical Analysis · Mathematics 2021-11-24 Xianchao Wang , Yukun Guo , Sara Bousba

We consider an anisotropic hyperbolic equation with memory term: $$ \partial_t^2 u(x,t) = \sum_{i,j=1}^n \partial_i(a_{ij}(x)\partial_ju) + \int^t_0 \sum_{| \alpha| \le 2} b_{\alpha}(x,t,\eta)\partial_x^{\alpha}u(x,\eta) d\eta + F(x,t) $$…

Analysis of PDEs · Mathematics 2017-12-06 Paola Loreti , Daniela Sforza , Masahiro Yamamoto

Total absorption, defined as the net flux of energy out of a bounded region averaged over one cycle for time harmonic motion, must be non-negative when there are no sources of energy within the region. This passivity condition places…

Classical Physics · Physics 2017-04-05 Andrew N. Norris

We consider the scattering of elastic waves by highly oscillating anisotropic periodic media with bounded support. Applying the two-scale homogenization, we first obtain a constant coefficient second-order partial differential elliptic…

Analysis of PDEs · Mathematics 2018-02-06 Yi-Hsuan Lin , Shixu Meng

Photoacoustic tomography seeks to reconstruct an acoustic initial pressure distribution from the measurement of the ultrasound waveforms. Conventional methods assume a-prior knowledge of the sound speed distribution, which practically is…

Image and Video Processing · Electrical Eng. & Systems 2019-09-16 Hongming Shan , Christopher Wiedeman , Ge Wang , Yang Yang

Optoacoustic tomography (OAT), also known as photoacoustic tomography, is a rapidly emerging hybrid imaging technique that possesses great potential for a wide range of biomedical imaging applications. In OAT, a laser is employed to…

Medical Physics · Physics 2016-12-21 Yang Lou , Kun Wang , Alexander. A. Oraevsky , Mark. A. Anastasio

We are concerned with the reconstruction of inclusions in elastic bodies based on measurements from a laboratory experiment. In doing so, we solve the inverse problem of the time-harmonic elastic wave equation, in contrast to the stationary…

Analysis of PDEs · Mathematics 2026-05-21 Sarah Eberle-Blick , Jochen Moll

Consider the scattering of an acoustic plane wave by a bounded elastic obstacle which is immersed in an open space filled with a homogeneous medium. This paper concerns the mathematical analysis of the coupled two- and three-dimensional…

Analysis of PDEs · Mathematics 2018-12-03 Peijun Li , Lei Zhang

In photoacoustic tomography (PAT), a hybrid imaging modality that is based on the acoustic detection of optical absorption from biological tissue exposed to a pulsed laser, a short pulse laser generates an initial pressure proportional to…

Numerical Analysis · Mathematics 2026-03-27 Sunghwan Moon , Anwesa Dey , Souvik Roy

We introduce a model-based iterative method to obtain shear modulus images of tissue using magnetic resonance elastography. The method jointly finds the displacement field that best fits multifrequency tissue displacement data and the…

Signal Processing · Electrical Eng. & Systems 2021-11-25 Shahed Mohammed , Mohammad Honarvar , Qi Zeng , Hoda Hashemi , Robert Rohling , Piotr Kozlowski , Septimiu Salcudean

Practical applications of thermoacoustic tomography require numerical inversion of the spherical mean Radon transform with the centers of integration spheres occupying an open surface. Solution of this problem is needed (both in 2-D and…

Analysis of PDEs · Mathematics 2009-11-13 Leonid Kunyansky
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