English
Related papers

Related papers: Thermoacoustic tomography with variable sound spee…

200 papers

A novel geometric formalism for statistical estimation is applied here to the canonical distribution of classical statistical mechanics. In this scheme thermodynamic states, or equivalently, statistical mechanical states, can be…

Quantum Physics · Physics 2009-10-30 Dorje C. Brody , Lane P. Hughston

A parameter estimation problem is considered for a one-dimensional stochastic wave equation driven by additive space-time Gaussian white noise. The estimator is of spectral type and utilizes a finite number of the spatial Fourier…

Probability · Mathematics 2008-10-02 W. Liu , S. V. Lototsky

We consider quantum state tomography with measurement procedures of the following type: First, we subject the quantum state we aim to identify to a know time evolution for a desired period of time. Afterwards we perform a measurement with a…

Quantum Physics · Physics 2017-01-24 Michael Kech

The holographic dual of a finite-temperature gauge theory with a small number of flavours typically contains D-brane probes in a black hole background. We have recently shown that these systems undergo a first order phase transition…

High Energy Physics - Theory · Physics 2010-04-06 David Mateos , Robert C. Myers , Rowan M. Thomson

The mathematical modeling of tumor growth leads to singular stiff pressure law limits for porous medium equations with a source term. Such asymptotic problems give rise to free boundaries, which, in the absence of active motion, are…

Analysis of PDEs · Mathematics 2015-07-06 Inwon C. Kim , Benoit Perthame , Panagiotis E. Souganidis

We study the speed of sound in strong-interaction matter at zero temperature and in density regimes which are expected to be governed by the presence of a color-superconducting gap. At (very) high densities, our analysis indicates that the…

Nuclear Theory · Physics 2024-05-07 Jens Braun , Andreas Geißel , Benedikt Schallmo

In this paper we provide bound estimates for the two fastest wave speeds emerging from the solution of the Riemann problem for three well-known hyperbolic systems, namely the Euler equations of gas dynamics, the shallow water equations and…

Numerical Analysis · Mathematics 2020-05-12 E. F. Toro , L. O. Müller , A. Siviglia

In this work, it is shown that image reconstruction methods from ultrasonic imaging can be employed for thermographic signals. Before using these imaging methods, a virtual signal is calculated by applying a local transformation to the…

Data Analysis, Statistics and Probability · Physics 2017-03-16 Peter Burgholzer , Michael Thor , Jürgen Gruber , Günther Mayr

We consider acoustic propagation in an irrotational vortex, using the technical machinery of differential geometry to investigate the ``acoustic geometry'' that is probed by the sound waves. The acoustic space-time curvature of a constant…

Condensed Matter · Physics 2007-05-23 Uwe R. Fischer , Matt Visser

For controlling the noise radiated from vibrating structures excited by turbulent boundary layer (TBL) it is relevant to develop numerical tools for understanding how the structure reacts to TBL excitation. Usually, the wall pressure…

Applied Physics · Physics 2024-09-23 Laurent Maxit , Marion Berton , Christian Audoly , Daniel Juvé

Ring-array ultrasound computed tomography has recently achieved sufficient maturity for clinical applications like breast imaging. Image reconstruction is achieved with state of art iterative algorithms (full waveform inversion in the…

Medical Physics · Physics 2025-08-14 Luca A. Forte

This paper aims to mathematically advance the field of quantitative thermo-acoustic imaging. Given several electromagnetic data sets, we establish for the first time an analytical formula for reconstructing the absorption coefficient from…

Analysis of PDEs · Mathematics 2014-03-25 Habib Ammari , Josselin Garnier , Wenjia Jing , Loc Nguyen

Conventional imaging of diagnostic ultrasound is widely used. Although it makes the differences in the soft tissues echogenicities' apparent and clear, it fails in describing and estimating the soft tissue mechanical properties. It cannot…

Medical Physics · Physics 2022-10-07 Hassan M. Ahmed

In this paper, we consider the stabilization of wave equations with moving boundary. First, we show the solution behaviour of wave equation with Neumann boundary conditions, that is, the energy of wave equation with mixed boundary…

Analysis of PDEs · Mathematics 2021-03-26 Lingyang Liu , Hang Gao

The boundary element method is an efficient algorithm for simulating acoustic propagation through homogeneous objects embedded in free space. The conditioning of the system matrix strongly depends on physical parameters such as density,…

Numerical Analysis · Mathematics 2021-12-07 Elwin van 't Wout , Seyyed R. Haqshenas , Pierre Gélat , Timo Betcke , Nader Saffari

We use thermal noise induced currents to image the real and imaginary parts of the conductivity of a body. Covariances of the thermal noise currents measured at a few electrodes are shown to be related to a deterministic problem. We use the…

Numerical Analysis · Mathematics 2023-05-10 Trent DeGiovanni , Fernando Guevara Vasquez , China Mauck

Hydrous phases play a fundamental role in the deep-water cycle on Earth. Understanding their stability and thermoelastic properties is essential for constraining their abundance using seismic tomography. However, determining their elastic…

Computational Physics · Physics 2025-04-09 Chenxing Luo , Yang Sun , Renata Wentzcovitch

We present an inexpensive apparatus for measuring the speed of sound, with a time of flight method, using a computer with a stereo sound board. Students measure the speed of sound by timing the delay between the arrivals of a pulse to two…

Physics Education · Physics 2009-11-13 Carlos C. Carvalho , J. M. B. Lopes dos Santos , M. B. Marques

We consider the propagation of acoustic time-harmonic waves in a homogeneous media containing periodic lattices of spherical or cylindrical inclusions. It is assumed that the wavelength has the order of the periods of the lattice while the…

Analysis of PDEs · Mathematics 2019-07-04 Yuri A. Godin , Boris Vainberg

We investigate general thermodynamic stability conditions for the superfluid. This analysis is performed in an extended space of thermodynamic variables containing (along with the usual thermodynamic coordinates such as pressure and…

Statistical Mechanics · Physics 2009-11-10 A. F. Andreev , L. A. Melnikovsky
‹ Prev 1 8 9 10 Next ›