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Ground-based solar image restoration is a computationally expensive procedure that involves nonlinear optimization techniques. The presence of atmospheric turbulence produces perturbations in individual images that make it necessary to…

Instrumentation and Methods for Astrophysics · Physics 2023-07-26 A. Asensio Ramos , S. Esteban Pozuelo , C. Kuckein

We derive a new 3D model for magnetic particle imaging (MPI) that is able to incorporate realistic magnetic fields in the reconstruction process. In real MPI scanners, the generated magnetic fields have distortions that lead to deformed…

Numerical Analysis · Mathematics 2020-12-30 Gaël Bringout , Wolfgang Erb , Jürgen Frikel

Optimizing the synthesis of zeolites and exploring novel frameworks offer pivotal opportunities and challenges in materials design. While inverse design proves highly effective for simpler crystals, its application to intricate structures…

Materials Science · Physics 2025-06-19 Chaohong Wang , Alberto Pérez de Alba Ortíz , Marjolein Dijkstra

Microwave inverse scattering imaging (MISI) is a crucial computational technique in microwave nondestructive evaluation and near-field microwave sensing systems. However, quantitative reconstruction of high-contrast targets remains a…

Signal Processing · Electrical Eng. & Systems 2026-05-26 Shilong Sun

Direct measurements of the stellar magnetic fields are based on the splitting of spectral lines into polarized Zeeman components. With few exceptions, Zeeman signatures are hidden in data noise and a number of methods have been developed to…

Inverse problems in computational physics often require matching high-dimensional spatio-temporal fields, leading to prohibitive computational costs and ill-conditioned optimizations. We introduce modal-centric field inversion (MCFI), a…

Numerical Analysis · Mathematics 2026-01-22 Rohit Sunil Kanchi , Sicheng He

Recently the field of inverse problems has seen a growing usage of mathematically only partially understood learned and non-learned priors. Based on first principles, we develop a projectional approach to inverse problems that addresses the…

Machine Learning · Computer Science 2019-08-07 Sören Dittmer , Peter Maass

We present our analysis aimed at inferring average magnetic fields in slowly-rotating solar-like stars. Using the spectral line inversion code SPINOR, we perform high-accuracy line profile fitting and investigate whether Zeeman broadening…

Solar and Stellar Astrophysics · Physics 2010-12-15 Richard I. Anderson , Ansgar Reiners , Sami K. Solanki

Inverse problems lie at the heart of modern imaging science, with broad applications in areas such as medical imaging, remote sensing, and microscopy. Recent years have witnessed a paradigm shift in solving imaging inverse problems, where…

Optimization and Control · Mathematics 2025-11-20 Hong Ye Tan , Subhadip Mukherjee , Junqi Tang

A big challenge in solar and stellar physics in the coming years will be to decipher the magnetism of the solar outer atmosphere (chromosphere and corona) along with its dynamic coupling with the magnetic fields of the underlying…

Astrophysics · Physics 2009-11-13 A. Asensio Ramos , J. Trujillo Bueno , E. Landi Degl'Innocenti

Doppler tomography is a method to compute the emissivity distribution within the co-rotating frames of binary stars from observations of their emission line profiles at multiple orbital phases. A key assumption of the method as it is…

Solar and Stellar Astrophysics · Physics 2021-12-08 T. R. Marsh

Angular and spectral differential imaging is an observational technique of choice to investigate the immediate vicinity of stars. The relative angular motion and spectral scaling between on-axis and off-axis sources are exploited by…

Instrumentation and Methods for Astrophysics · Physics 2024-10-04 Olivier Flasseur , Loïc Denis , Éric Thiébaut , Maud Langlois

Many challenging image processing tasks can be described by an ill-posed linear inverse problem: deblurring, deconvolution, inpainting, compressed sensing, and superresolution all lie in this framework. Traditional inverse problem solvers…

Computer Vision and Pattern Recognition · Computer Science 2019-06-05 Davis Gilton , Greg Ongie , Rebecca Willett

We propose a formulation of full-wavefield inversion (FWI) as a constrained optimization problem, and describe a computationally efficient technique for solving constrained full-wavefield inversion (CFWI). The technique is based on using a…

Geophysics · Physics 2014-10-28 Musa Maharramov , Biondo Biondi

Full-waveform inversion (FWI) is a powerful geophysical imaging technique that infers high-resolution subsurface physical parameters by solving a non-convex optimization problem. However, due to limitations in observation, e.g., limited…

Numerical Analysis · Mathematics 2023-11-09 Xiong-Bin Yan , Keke Wu , Zhi-Qin John Xu , Zheng Ma

Reconstructing magnetization in nanoscale magnetic thin films is essential for developing next-generation memory, sensors, and various spintronic technologies. However, this remains challenging due to the ill-posed nature of the stray field…

Disordered Systems and Neural Networks · Physics 2026-04-28 Zander Scholl , Justin Woods , Charudatta Phatak , Hanu Arava

As a challenging vision-language task, Zero-Shot Composed Image Retrieval (ZS-CIR) is designed to retrieve target images using bi-modal (image+text) queries. Typical ZS-CIR methods employ an inversion network to generate pseudo-word tokens…

Computer Vision and Pattern Recognition · Computer Science 2025-08-07 Haiwen Li , Fei Su , Zhicheng Zhao

Despite all recent progress, it is still challenging to edit and manipulate natural images with modern generative models. When using Generative Adversarial Network (GAN), one major hurdle is in the inversion process mapping a real image to…

Computer Vision and Pattern Recognition · Computer Science 2023-09-12 Zhihong Pan , Riccardo Gherardi , Xiufeng Xie , Stephen Huang

In radio astronomy obtaining a high dynamic range in synthesis imaging of wide fields requires a correction for time and direction-dependent effects. Applying direction-dependent correction can be done by either partitioning the image in…

Instrumentation and Methods for Astrophysics · Physics 2019-09-17 Sebastiaan van der Tol , Bram Veenboer , André R. Offringa

By studying young magnetically active late-type stars, i.e. analogues to the young Sun, one can draw conclusions on the evolution of the solar dynamo. We determine the topology of the surface magnetic field and study the relation between…

Solar and Stellar Astrophysics · Physics 2016-03-02 Thomas Hackman , Jyri Lehtinen , Lisa Rosén , Oleg Kochukhov , Maarit J. Käpylä