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Related papers: Multi-frequency acousto-electromagnetic tomography

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We consider the inverse problem of quantitative reconstruction of properties (e.g., bulk modulus, density) of visco-acoustic materials based on measurements of responding waves after stimulation of the medium. Numerical reconstruction is…

Analysis of PDEs · Mathematics 2022-09-20 Florian Faucher , Otmar Scherzer

This paper proposes a novel approach to reconstruct changes in a target conductivity from electrical impedance tomography measurements. As in the conventional difference imaging, the reconstruction of the conductivity change is based on…

Computational Physics · Physics 2014-03-27 Dong Liu , Ville Kolehmainen , Samuli Siltanen , Anne maria Laukkanen , Aku Seppanen

In this work we investigate the numerical identification of the diffusion coefficient in elliptic and parabolic problems using neural networks. The numerical scheme is based on the standard output least-squares formulation where the…

Numerical Analysis · Mathematics 2023-02-22 Siyu Cen , Bangti Jin , Qimeng Quan , Zhi Zhou

Coherent diffractive imaging is a technique that recovers the sample image by numerically inverting its diffraction pattern. We propose a generalization of this method for the inversion of multi-wavelength data. Using this approach, we show…

Optics · Physics 2020-05-08 Erik Malm , Edwin Fohtung , Anders Mikkelsen

Photoacoustic tomography is a hybrid imaging technique that combines high optical tissue contrast with high ultrasound resolution. Direct reconstruction methods such as filtered backprojection, time reversal and least squares suffer from…

We present a novel approach to transcranial ultrasound computed tomography that utilizes normalizing flows to improve the speed of imaging and provide Bayesian uncertainty quantification. Our method combines physics-informed methods and…

Image and Video Processing · Electrical Eng. & Systems 2023-03-08 Rafael Orozco , Mathias Louboutin , Ali Siahkoohi , Gabrio Rizzuti , Tristan van Leeuwen , Felix Herrmann

We propose and characterize experimentally a new source of optical frequency combs for performing multi-heterodyne spectrometry. This comb modality is based on a frequency shifting loop seeded with a CW monochromatic laser. The comb lines…

Optics · Physics 2018-07-04 V. Duran , C. Schnebelin , H. Guillet De Chatellus

New techniques for imaging electromagnetic near-fields in nanostructures drive advancements in nanotechnology, optoelectronics, materials science, and biochemistry. Most existing techniques probe near-fields along surfaces, lacking the…

In this work, an inverse problem on the determination of multiple coefficients arising from the time-domain diffuse optical tomography with fluorescence (DOT-FDOT) is investigated. We simultaneously recover the distribution of background…

Numerical Analysis · Mathematics 2023-11-23 Zhiyuan Li , Chunlong Sun

This paper presents a paraxial modeling approach for vibro-acoustography, a high-frequency ultrasound imaging technique that makes use of the excited low-frequency field to achieve a higher resolution while avoiding speckles. We start from…

Numerical Analysis · Mathematics 2023-10-06 Teresa Rauscher

Entangled photons (biphotons) in the time-frequency degree of freedom play a crucial role in both foundational physics and advanced quantum technologies. Fully characterizing them poses a key scientific challenge. Here, we propose a…

Quantum Physics · Physics 2024-03-22 Baihong Li , Changhua Chen , Boxin Yuan , Xiaofei Zhang , Ruifang Dong , Shougang Zhang , Rui-Bo Jin

Conventional photoacoustic imaging may suffer from the limited view and bandwidth of ultrasound transducers. A deep learning approach is proposed to handle these problems and is demonstrated both in simulations and in experiments on a…

Image and Video Processing · Electrical Eng. & Systems 2020-11-19 Guillaume Godefroy , Bastien Arnal , Emmanuel Bossy

A multiscale QM/classical approach is presented, that is able to model the optical properties of complex nanostructures composed of a molecular system adsorbed on metal nanoparticles. The latter are described by a combined…

Chemical Physics · Physics 2024-10-29 Pablo Grobas Illobre , Piero Lafiosca , Luca Bonatti , Tommaso Giovannini , Chiara Cappelli

We propose and investigate efficient numerical methods for inverse problems related to Magnetic Resonance Imaging (MRI). Our goal is to extend the recent convergence results for the Landweber-Kaczmarz method obtained in [Haltmeier, Leitao,…

Numerical Analysis · Mathematics 2020-12-22 A. Leitao , J. Zubelli

Understanding how the D-Wave quantum computer could be used for machine learning problems is of growing interest. Our work evaluates the feasibility of using the D-Wave as a sampler for machine learning. We describe a hybrid system that…

Quantum Physics · Physics 2020-02-03 Jennifer Sleeman , John Dorband , Milton Halem

Ptychography, a prevalent imaging technique in fields such as biology and optics, poses substantial challenges in its reconstruction process, characterized by nonconvexity and large-scale requirements. This paper presents a novel approach…

Numerical Analysis · Mathematics 2024-03-25 Kevin Bui , Zichao Di

In electrical impedance tomography, algorithms based on minimizing the linearized-data-fit residuum have been widely used due to their real-time implementation and satisfactory reconstructed images. However, the resulting images usually…

Analysis of PDEs · Mathematics 2019-03-25 Bastian Harrach , Mach Nguyet Minh

In this paper, we show that using measurements for different frequencies, and using ultrasound localized perturbations it is possible to extend the method of the imaging by elastic deformation developed by Ammari and al. [Electrical…

Analysis of PDEs · Mathematics 2010-04-21 Anna Rozanova-Pierrat

This paper concerns the quantitative step of the medical imaging modality Thermo-acoustic Tomography (TAT). We model the radiation propagation by a system of Maxwell's equations. We show that the index of refraction of light and the…

Analysis of PDEs · Mathematics 2015-06-17 Guillaume Bal , Ting Zhou

Scattering by an isolated defect embedded in a dielectric medium of two dimensional periodicity is of interest in many sub-fields of electrodynamics. Present approaches to compute this scattering rely either on the Born approximation and…

Mesoscale and Nanoscale Physics · Physics 2021-05-10 Kuljit S. Virk
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