Results 11 to 20 of about 302 (108)

MRI at low field: A review of software solutions for improving SNR. [PDF]

NMR Biomed
The re‐emerging interest we see in low‐field MRI brings signal sensitivity and imaging performance at the core of current research. An overview of software strategies to enhance signal‐to‐noise ratio per unit time at low field (B0 < 1 T) is provided that covers k‐space sampling techniques, reconstruction, post‐processing, and electromagnetic ...
Ayde R, Vornehm M, Zhao Y, Knoll F, Wu EX, Sarracanie M.   +5 more
europepmc   +2 more sources

Application of MLEM‐TV Algorithm in Diffuse Correlation Tomography Blood Flow Imaging

International Journal of Imaging Systems and Technology, Volume 36, Issue 1, January 2026.
ABSTRACT Diffuse correlation tomography (DCT) reconstructs the motion velocity of scatterers (blood flow index, BFI) within biological tissues by using information from the escaped photons. Given the randomness of a single scatterer motion and the determinism of particle swarm, the motion of scatterers was analyzed for the first time using a ...
Zicheng Li, Dalin Cheng, Juanjuan Shen, Xiaojuan Zhang   +3 more
wiley   +1 more source

Performance Analysis of Iterative Methods in Microwave Imaging With Various Regularization Techniques

IEEE Open Journal of Antennas and Propagation
Quantitative microwave imaging (MWI) involves solving the inverse scattering problem (ISP), which is characterized by nonlinearity and ill-posedness.
Reihaneh Ahmadi Vanhari, Ahmad Bakhtafrouz, Sima Noghanian   +2 more
doaj   +1 more source

Regularization by Global DGMRES Method for Ill‐Posed Matrix Equation AXB = G

Advances in Mathematical Physics, Volume 2026, Issue 1, 2026.
In this article, we deal with the solution of the linear, large‐size, and ill‐posed matrix equation AXB = G, whose matrix G is contaminated with noise. We apply Tikhonov regularization in combination with the Gl‐DGMRES method to mitigate the effect of noise.
Vahid Hosseinabadi, Hossein Sadeghi Goughery, Mahnoor Sarfraz   +2 more
wiley   +1 more source

Ill-posedness in limited discrete Fourier inversion and regularization for quasi distributions in LaMET

European Physical Journal C: Particles and Fields
We systematically investigated the limited inverse discrete Fourier transform of the quasi distributions from the perspective of inverse problem theory. This transformation satisfies two of Hadamard’s well-posedness criteria, existence and uniqueness of ...
Ao-Sheng Xiong, Jun Hua, Yu-Fei Ling, Ting Wei, Fu-Sheng Yu, Qi-An Zhang, Yong Zheng   +6 more
doaj   +1 more source

Modeling Regional Electric Field Using EISCAT3D Observations

Journal of Geophysical Research: Space Physics, Volume 130, Issue 10, October 2025.
Abstract EISCAT3D, which is in its final stage of construction, will be the next generation incoherent scatter radar (ISR) system to provide the full ion velocity vector across hundreds of kms in vertical and horizontal directions. This presents a tremendous opportunity to study the three‐dimensional nature of ionospheric electrodynamics.
Habtamu W. Tesfaw, Heikki Vanhamäki, Ilkka Virtanen, Spencer Hatch, Matt Zettergren, Karl Laundal   +5 more
wiley   +1 more source

Regularization in Structural Model Updating in the Presence of Noisy Data

International Journal for Numerical Methods in Engineering, Volume 126, Issue 17, 15 September 2025.
ABSTRACT This article addresses the presence of noise when solving the inverse problem of determining the material properties of an elastic engineering structure from measured vibration data. After identifying the frequencies, material properties are determined by solving an optimization problem. However, if the experimental frequencies are affected by
Maria Girardi, Cristina Padovani, Daniele Pellegrini, Leonardo Robol   +3 more
wiley   +1 more source

Data‐driven methods for quantitative imaging

GAMM-Mitteilungen, Volume 48, Issue 1, March 2025.
Abstract In the field of quantitative imaging, the image information at a pixel or voxel in an underlying domain entails crucial information about the imaged matter. This is particularly important in medical imaging applications, such as quantitative magnetic resonance imaging (qMRI), where quantitative maps of biophysical parameters can characterize ...
Guozhi Dong, Moritz Flaschel, Michael Hintermüller, Kostas Papafitsoros, Clemens Sirotenko, Karsten Tabelow   +5 more
wiley   +1 more source

An interior inverse generalized impedance problem for the modified Helmholtz equation in two dimensions

ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, Volume 105, Issue 1, January 2025.
Abstract We consider the inverse interior problem of recovering the surface impedances of the cavity from sources and measurements placed on a curve inside of it. The uniqueness issue is investigated, and a hybrid method is proposed for the numerical solution.
Olha Ivanyshyn Yaman, Gazi Özdemir
wiley   +1 more source

Physics‐Informed Estimation of Tidal and Subtidal Flow Fields From ADCP Repeat Transect Data

Water Resources Research, Volume 61, Issue 1, January 2025.
Abstract Acoustic Doppler current profilers (ADCPs) are a global standard in observing flow fields in rivers, estuaries and the coastal ocean. To date, it remains a labor intensive challenge to isolate mean flow fields governed by river discharge, tides and atmospheric forcing on the one hand, from small‐scale turbulence, positioning imprecision ...
H. Jongbloed, B. Vermeulen, A. J. F. Hoitink   +2 more
wiley   +1 more source