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In meteorology, engineering and computer sciences, data assimilation is routinely employed as the optimal way to combine noisy observations with prior model information for obtaining better estimates of a state, and thus better forecasts,…

Geophysics · Physics 2009-08-12 M. J. Werner , K. Ide , D. Sornette

Current and upcoming cosmological surveys will produce unprecedented amounts of high-dimensional data, which require complex high-fidelity forward simulations to accurately model both physical processes and systematic effects which describe…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-11 Aizhan Akhmetzhanova , Carolina Cuesta-Lazaro , Siddharth Mishra-Sharma

We present a two-component Machine Learning (ML) based approach for classifying astronomical images by data-quality via an examination of sources detected in the images and image pixel values from representative sources within those images.…

Instrumentation and Methods for Astrophysics · Physics 2020-04-01 Hossen Teimoorinia , J. J. Kavelaars , Stephen Gwyn , Daniel Durand , Kennedy Rolston , Alexander Ouellette

The production of science-ready data from major solar telescopes requires expertise beyond that of the typical observer. This is a consequence of the increasing complexity of instruments and observing sequences, which require calibrations…

Solar and Stellar Astrophysics · Physics 2014-12-17 J. de la Cruz Rodríguez , M. Löfdahl , P. Sütterlin , T. Hillberg , L. Rouppe van der Voort

Deconvolution of astronomical images is a key aspect of recovering the intrinsic properties of celestial objects, especially when considering ground-based observations. This paper explores the use of diffusion models (DMs) and the Diffusion…

Instrumentation and Methods for Astrophysics · Physics 2025-01-22 Alessio Spagnoletti , Alexandre Boucaud , Marc Huertas-Company , Wassim Kabalan , Biswajit Biswas

The non-linearities of the dynamics of Earth artificial satellites are encapsulated by two formal integrals that are customarily computed by perturbation methods. Standard procedures begin with a Hamiltonian simplification that removes…

Dynamical Systems · Mathematics 2020-09-23 Martin Lara

The large scale structure of the universe is a complex web of clusters, filaments, and voids. Its properties are informed by galaxy redshift surveys and measurements of peculiar velocities. Wiener Filter reconstructions recover…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Helene M. Courtois , Daniel Pomarede , R. Brent Tully , Yehuda Hoffman , Denis Courtois

We present a data-driven method for reconstructing the galactic acceleration field from phase-space measurements of stellar streams. Our approach is based on a flexible and differentiable fit to the stream in phase-space, enabling a direct…

Astrophysics of Galaxies · Physics 2023-03-31 Jacob Nibauer , Vasily Belokurov , Miles Cranmer , Jeremy Goodman , Shirley Ho

Data analysis methods have always been of critical importance for quantitative sciences. In astronomy, the increasing scale of current and future surveys is driving a trend towards a separation of the processes of low-level data reduction…

Instrumentation and Methods for Astrophysics · Physics 2011-09-07 James Bosch

We suggest a two-dimensional wavelet devised to deduce the large-scale structure of a physical field (e.g., the Galactic magnetic field) from its integrals along straight paths from irregularly spaced data points to a fixed interior point…

Astrophysics · Physics 2009-11-07 R. Stepanov , P. Frick , A. Shukurov , D. Sokoloff

Proton radiography is a technique extensively used to resolve magnetic field structures in high energy density plasmas, revealing a whole variety of interesting phenomena such as magnetic reconnection and collisionless shocks found in…

We present a novel approach to construct cosmological models endowed with a particular scalar field, the stealth. The model is constructed by studying a scalar field no-minimally coupled to the gravitational field with sources; as sources,…

General Relativity and Quantum Cosmology · Physics 2018-09-26 Abigail Alvarez , Cuauhtemoc Campuzano , Víctor Cárdenas , Efraín Rojas

B-spline models are a powerful way to represent scientific data sets with a functional approximation. However, these models can suffer from spurious oscillations when the data to be approximated are not uniformly distributed. Model…

Numerical Analysis · Mathematics 2022-03-29 David Lenz , Raine Yeh , Vijay Mahadevan , Iulian Grindeanu , Tom Peterka

Data assimilation combines information from physical observations and numerical simulation results to obtain better estimates of the state and parameters of a physical system. A wide class of physical systems of interest have solutions that…

Optimization and Control · Mathematics 2025-05-02 Amit N. Subrahmanya , Adrian Sandu

Recent years have seen the development of mature solutions for reconstructing deformable surfaces from a single image, provided that they are relatively well-textured. By contrast, recovering the 3D shape of texture-less surfaces remains an…

Computer Vision and Pattern Recognition · Computer Science 2018-07-30 Jan Bednařík , Pascal Fua , Mathieu Salzmann

We address the question of astronomical image processing from data obtained with array detectors. We define and analyze the cases of evenly, regularly, and irregularly sampled maps for idealized (i.e., infinite) and realistic (i.e., finite)…

Astrophysics · Physics 2009-11-13 Martin Houde , John E. Vaillancourt

We present a principled Bayesian framework for signal reconstruction, in which the signal is modelled by basis functions whose number (and form, if required) is determined by the data themselves. This approach is based on a Bayesian…

Instrumentation and Methods for Astrophysics · Physics 2019-01-23 Edward Higson , Will Handley , Michael Hobson , Anthony Lasenby

In order to extract maximal information about cosmology from the large-scale structure of the Universe, one needs to use every bit of signal that can be observed. Beyond the spatial distributions of astronomical objects, the spatial…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-23 Takahiko Matsubara

When using constellation synergy to image large areas for reconnaissance, it is required to achieve the coverage capability requirements with minimal consumption of observation resources to obtain the most optimal constellation observation…

Computer Vision and Pattern Recognition · Computer Science 2022-12-07 Jiahao Zhou , Boheng Li , Qingxiang Meng

The tidal gravitational field of galaxy clusters causes a coherent distortion of the images of background sources. Since the distribution of image distortions, namely the shear field, traces the local gravitational potential of a deflector,…

Astrophysics · Physics 2016-08-30 Keiichi Umetsu , Masashi Tada , Toshifumi Futamase
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