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Related papers: Sparse Bayesian Imaging of Solar Flares

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Knowing the behavior of solar radiation at a geographic location is essential for the use of energy from the sun using photovoltaic systems; however, the number of stations for measuring meteorological parameters and for determining the…

Machine Learning · Computer Science 2022-04-13 Luis Eduardo Ordoñez Palacios , Víctor Bucheli Guerrero , Hugo Ordoñez

This paper investigates a novel a-posteriori variance reduction approach in Monte Carlo image synthesis. Unlike most established methods based on lateral filtering in the image space, our proposition is to produce the best possible estimate…

Graphics · Computer Science 2019-06-04 Oskar Elek , Manu M. Thomas , Angus Forbes

Given the rarity of significant solar flares compared to smaller ones, training effective machine learning models for solar activity forecasting is challenging due to insufficient data. This study proposes using generative deep learning…

Solar and Stellar Astrophysics · Physics 2024-04-04 Francesco P. Ramunno , S. Hackstein , V. Kinakh , M. Drozdova , G. Quetant , A. Csillaghy , S. Voloshynovskiy

Solar flares are complicated physical phenomena that are observable in a broad range of the electromagnetic spectrum, from radiowaves to $\gamma$-rays. For a more comprehensive understanding of flares, it is necessary to perform a combined…

Solar and Stellar Astrophysics · Physics 2017-08-02 Viacheslav M Sadykov , Alexander G Kosovichev , Vincent Oria , Gelu M Nita

The dark sirens method combines gravitational waves and catalogs of galaxies to constrain the cosmological expansion history, merger rates and mass distributions of compact objects, and the laws of gravity. However, the incompleteness of…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-09 Konstantin Leyde , Tessa Baker , Wolfgang Enzi

To date weak gravitational lensing surveys have typically been restricted to small fields of view, such that the $\textit{flat-sky approximation}$ has been sufficiently satisfied. However, with Stage IV surveys ($\textit{e.g. LSST}$ and…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-19 Matthew A. Price , Jason D. McEwen , L. Pratley , Thomas D. Kitching

Rendering high-fidelity images from sparse point clouds is still challenging. Existing learning-based approaches suffer from either hole artifacts, missing details, or expensive computations. In this paper, we propose a novel framework to…

Computer Vision and Pattern Recognition · Computer Science 2024-07-08 Jiaxu Wang , Ziyi Zhang , Junhao He , Renjing Xu

Image or object recognition is an important task in computer vision. With the hight-speed processing power on modern platforms and the availability of mobile phones everywhere, millions of photos are uploaded to the internet per minute, it…

Computer Vision and Pattern Recognition · Computer Science 2017-06-06 Yong Khoo , Seo-hyeon Keun

Statistical inference with nonresponse is quite challenging, especially when the response mechanism is nonignorable. In this case, the validity of statistical inference depends on untestable correct specification of the response model. To…

Methodology · Statistics 2021-01-15 Shonosuke Sugasawa , Kosuke Morikawa , Keisuke Takahata

We consider the situation where a temporal process is composed of contiguous segments with differing slopes and replicated noise-corrupted time series measurements are observed. The unknown mean of the data generating process is modelled as…

Solar storms can have a major impact on the infrastructure of the earth. Some of the causing events are observable from ground in the H{\alpha} spectral line. In this paper we propose a new method for the simultaneous detection of flares…

Computer Vision and Pattern Recognition · Computer Science 2013-04-29 Gernot Riegler , Thomas Pock , Werner Pötzi , Astrid Veronig

We propose a forecasting approach for solar flares based on data from Solar Cycle 24, taken by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) mission. In particular, we use the Space-weather HMI…

Photometric pipelines struggle to estimate both the flux and flux uncertainty for stars in the presence of structured backgrounds such as filaments or clouds. However, it is exactly stars in these complex regions that are critical to…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Andrew K. Saydjari , Douglas P. Finkbeiner

A popular scenario for electron acceleration in solar flares is transit-time damping of low-frequency MHD waves excited by reconnection and its outflows. The scenario requires several processes in sequence to yield energetic electrons of…

Astrophysics · Physics 2015-06-24 Arnold O. Benz , Pascal Saint-Hilaire

Simultaneous solar flare observations with SDO and RHESSI provide spatially resolved information about hot plasma and energetic particles in flares. RHESSI allows the properties of both hot (> 8 MK) thermal plasma and nonthermal electron…

Solar and Stellar Astrophysics · Physics 2015-06-17 Marina Battaglia , Eduard P. Kontar

A common task in inverse problems and imaging is finding a solution that is sparse, in the sense that most of its components vanish. In the framework of compressed sensing, general results guaranteeing exact recovery have been proven. In…

Numerical Analysis · Mathematics 2021-04-29 Monica Pragliola , Daniela Calvetti , Erkki Somersalo

We propose a Bayesian image super-resolution (SR) method with a causal Gaussian Markov random field (MRF) prior. SR is a technique to estimate a spatially high-resolution image from given multiple low-resolution images. An MRF model with…

Computer Vision and Pattern Recognition · Computer Science 2015-05-30 Takayuki Katsuki , Akira Torii , Masato Inoue

Frequentist and likelihood methods of inference based on the multivariate skew-normal model encounter several technical difficulties with this model. In spite of the popularity of this class of densities, there are no broadly satisfactory…

Methodology · Statistics 2013-02-06 Brunero Liseo , Antonio Parisi

Gaussian time-series models are often specified through their spectral density. Such models present several computational challenges, in particular because of the non-sparse nature of the covariance matrix. We derive a fast approximation of…

Computation · Statistics 2012-11-20 Nicolas Chopin , Judith Rousseau , Brunero Liseo

A Monte Carlo program based on a three dimensional vector approach was developed to model multiple refractive scattering of X-ray photons in objects with a fine structure. A particular interest was paid to the investigation of lung tissue.…

Medical Physics · Physics 2010-02-02 Anastasiya Khromova