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Recent advances have made it possible to obtain two-dimensional line-of-sight magnetic field maps of the solar corona from spectropolarimetric observations of the Fe XIII 1075 nm forbidden coronal emission line. Together with the linear…

Astrophysics · Physics 2009-11-13 Yu Liu , Haosheng Lin

Cardiac cine MRI is the gold standard for cardiac functional assessment, but the inherently slow acquisition process creates the necessity of reconstruction approaches for accelerated undersampled acquisitions. Several regularization…

Image and Video Processing · Electrical Eng. & Systems 2023-07-28 Tabita Catalán , Matías Courdurier , Axel Osses , René Botnar , Francisco Sahli Costabal , Claudia Prieto

Context. On the sun, the magnetic field vector is measured routinely only in the photosphere. By using these photospheric measurements as boundary condition, we developed the magnetohydrostatic (MHS) extrapolation to model the solar…

Solar and Stellar Astrophysics · Physics 2019-11-20 Xiaoshuai Zhu , Thomas Wiegelmann

We present Neural Kernel Fields: a novel method for reconstructing implicit 3D shapes based on a learned kernel ridge regression. Our technique achieves state-of-the-art results when reconstructing 3D objects and large scenes from sparse…

Computer Vision and Pattern Recognition · Computer Science 2021-11-29 Francis Williams , Zan Gojcic , Sameh Khamis , Denis Zorin , Joan Bruna , Sanja Fidler , Or Litany

An efficient computational approach for optimal reconstruction of binary-type images suitable for models in various applications including biomedical imaging is developed and validated. The methodology includes derivative-free optimization…

Optimization and Control · Mathematics 2022-09-27 Paul R. Arbic , Vladislav Bukshtynov

Diagnosing solar flare conditions is essential for understanding coronal energy release. Using combined microwave and X-ray data, we reconstruct three-dimensional maps of the magnetic field and plasma parameters in the SOL2021-05-07 flare.…

Solar and Stellar Astrophysics · Physics 2026-03-06 Tatyana Kaltman , Sijie Yu , Gregory D. Fleishman , Daniel F. Ryan

This article presents the first direct "observation" of the global-scale, 3D coronal magnetic fields of Carrington Rotation (CR) Cycle 2112 using vector tomographic inversion techniques. The Vector tomographic inversion uses observational…

Solar and Stellar Astrophysics · Physics 2016-07-18 M. Kramar , H. Lin , S. Tomczyk

Properties of magnetic field in the internetwork regions are still fairly unknown due to rather weak spectropolarimetric signals. We address the matter by using the 2D inversion code that is able to retrieve the information on smallest…

Solar and Stellar Astrophysics · Physics 2016-10-05 S. Danilovic , M. van Noort , M. Rempel

Circuit models involving bulk currents and inductances are often used to estimate the energies of coronal magnetic field configurations, in particular configurations associated with solar flares. The accuracy of circuit models is tested by…

Astrophysics · Physics 2009-11-10 M. S. Wheatland , F. J. Farvis

Fueled by their excellent stiffness-to-weight ratio and the availability of mature manufacturing technologies, filament wound carbon fiber reinforced polymers represent ideal materials for thin-walled laminate structures. However, their…

Applied Physics · Physics 2019-09-17 Marek Tyburec , Jan Zeman , Jan Novák , Matěj Lepš , Tomáš Plachý , Robin Poul

We present a new approach for computing planar hexagonal meshes that approximate a given surface, represented as a triangle mesh. Our method is based on two novel technical contributions. First, we introduce Coordinate Power Fields, which…

Graphics · Computer Science 2021-05-07 Kacper Pluta , Michal Edelstein , Amir Vaxman , Mirela Ben-Chen

We present a robust optimization algorithm for the design of electromagnetic coils that generate vacuum magnetic fields with nested flux surfaces and precise quasi-symmetry. The method is based on a bilevel optimization problem, where the…

Plasma Physics · Physics 2023-04-26 Andrew Giuliani , Florian Wechsung , Antoine Cerfon , Matt Landreman , Georg Stadler

Given a known radial magnetic field distribution on the Sun's photospheric surface, there exist well-established methods for computing a potential magnetic field in the corona above. Such potential fields are routinely used as input to…

Solar and Stellar Astrophysics · Physics 2021-12-22 Oliver E. K. Rice , Anthony R. Yeates

Four different approximate approaches used to model the stressing of coronal magnetic fields due to an imposed photospheric motion are compared with each other and the results from a full time-dependent magnetohydrodynamic (MHD) code. The…

Solar and Stellar Astrophysics · Physics 2018-02-28 E. E. Goldstraw , A. W. Hood , P. K. Browning , P. J. Cargill

The finite-element analysis of three-dimensional magnetostatic problems in terms of magnetic vector potential has proven to be one of the most efficient tools capable of providing the excellent quality results but becoming computationally…

Computational Physics · Physics 2023-07-25 Alexander Chervyakov

We present the first reconstruction of the three-dimensional shape of magnetic loops in an active region from two different vantage points based on simultaneously recorded images. The images were taken by the two EUVI telescopes of the…

Astrophysics · Physics 2008-02-07 L. Feng , B. Inhester , S. K. Solanki , T. Wiegelmann , B. Podlipnik , R. A. Howard , J. -P. Wuelser

In the burgeoning field of medical imaging, precise computation of 3D volume holds a significant importance for subsequent qualitative analysis of 3D reconstructed objects. Combining multivariate calculus, marching cube algorithm, and…

Graphics · Computer Science 2026-04-29 Quoc-Bao Nguyen-Le , Tuan-Hy Le , Anh-Triet Do

We provide a mathematical analysis and a numerical framework for magnetoacoustic tomography with magnetic induction. The imaging problem is to reconstruct the conductivity distribution of biological tissue from measurements of the Lorentz…

Analysis of PDEs · Mathematics 2015-08-05 Habib Ammari , Simon Boulier , Pierre Millien

Hybrid magnetic shields with both active field generating components and high-permeability magnetic shielding are increasingly needed for a variety of technologies and experiments that require precision-controlled magnetic field…

Applied Physics · Physics 2021-06-04 M. Packer , P. J. Hobson , N. Holmes , J. Leggett , P. Glover , M. J. Brookes , R. Bowtell , T. M. Fromhold

Magnetic confinement devices for nuclear fusion can be large and expensive. Compact stellarators are promising candidates for costreduction, but introduce new difficulties: confinement in smaller volumes requires higher magnetic field,…

Optimization and Control · Mathematics 2022-07-13 Rémi Robin , Francesco Volpe