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We propose a data-driven approach to quantify the uncertainty of models constructed by kernel methods. Our approach minimizes the needed distributional assumptions, hence, instead of working with, for example, Gaussian processes or…

Machine Learning · Computer Science 2019-08-06 Balázs Csanád Csáji , Krisztián Balázs Kis

Phenomenological models of cosmic-ray (CR) transport in the Milky Way (MW) can reproduce a wide range of observations assuming that CRs scatter off of magnetic-field fluctuations with spectrum $\propto k^{-\delta}$ and $\delta \sim…

High Energy Astrophysical Phenomena · Physics 2022-06-15 Philipp Kempski , Eliot Quataert

We use a publicly available numerical wave-propagation simulation of Hartlep et al. 2011 to test the ability of helioseismic holography to detect signatures of a compact, fully submerged, 5% sound-speed perturbation placed at a depth of 50…

Solar and Stellar Astrophysics · Physics 2015-06-11 Douglas C. Braun

The Helioseismic and Magnetic Imager onboard the Solar Dynamics Observatory (SDO/HMI) provides continuous full-disk observations of solar oscillations. We develop a data-analysis pipeline based on the time-distance helioseismology method to…

Solar and Stellar Astrophysics · Physics 2015-05-27 J. Zhao , S. Couvidat , R. S. Bogart , K. V. Parchevsky , A. C. Birch , T. L. Duvall , J. G. Beck , A. G. Kosovichev , P. H. Scherrer

Investigation of propagation, conversion, and scattering of MHD waves in the Sun is very important for understanding the mechanisms of observed oscillations and waves in sunspots and active regions. We have developed 3D linear MHD numerical…

Astrophysics · Physics 2011-02-11 K. V. Parchevsky , A. G. Kosovichev

We show that geometric inference of a point cloud can be calculated by examining its kernel density estimate with a Gaussian kernel. This allows one to consider kernel density estimates, which are robust to spatial noise, subsampling, and…

Computational Geometry · Computer Science 2015-03-27 Jeff M. Phillips , Bei Wang , Yan Zheng

Stellar photometric variability and instrumental effects, like cosmic ray hits, data discontinuities, data leaks, instrument aging etc. cause difficulties in the characterization of exoplanets and have an impact on the accuracy and…

Earth and Planetary Astrophysics · Physics 2023-07-12 Sz. Csizmadia , A. M. S. Smith , J. Cabrera , P. Klagyivik , A. Chaushev , K. W. F. Lam

Strongly lensed variable quasars can serve as precise cosmological probes, provided that time delays between the image fluxes can be accurately measured. A number of methods have been proposed to address this problem. In this paper, we…

Instrumentation and Methods for Astrophysics · Physics 2016-03-15 Sultanah AL Otaibi , Peter Tiňo , Juan C Cuevas-Tello , Ilya Mandel , Somak Raychaudhury

Kernel regression is an essential and ubiquitous tool for non-parametric data analysis, particularly popular among time series and spatial data. However, the central operation which is performed many times, evaluating a kernel on the data…

Machine Learning · Computer Science 2017-06-01 Yan Zheng , Jeff M. Phillips

High dimensional structured data such as text and images is often poorly understood and misrepresented in statistical modeling. The standard histogram representation suffers from high variance and performs poorly in general. We explore…

Machine Learning · Computer Science 2012-06-26 Joshua Dillon , Yi Mao , Guy Lebanon , Jian Zhang

Inferring interior properties of the Sun from photospheric measurements of the seismic wavefield constitutes the helioseismic inverse problem. Deviations in seismic measurements (such as wave travel times) from their fiducial values…

Solar and Stellar Astrophysics · Physics 2015-06-18 Shravan Hanasoge , Jeroen Tromp

The origins of the hot solar corona and the supersonically expanding solar wind are still the subject of debate. A key obstacle in the way of producing realistic simulations of the Sun-heliosphere system is the lack of a physically…

Solar and Stellar Astrophysics · Physics 2014-11-20 Steven R. Cranmer

Quantum kernels offer a valid procedure for learning quantum phase transitions on quantum processing devices, yet issues on the scalability of the learning strategy in connection with the symmetry of the critical model have not been…

Quantum Physics · Physics 2026-03-20 Aaqib Ali , Giovanni Scala , Cosmo Lupo , Antonio Mandarino

We present a study of sound wave propagation in a time dependent random medium and an application to imaging. The medium is modeled by small temporal and spatial random fluctuations in the wave speed and density, and it moves due to an…

Analysis of PDEs · Mathematics 2018-06-19 Liliana Borcea , Josselin Garnier , Knut Solna

Kernel random matrices have attracted a lot of interest in recent years, from both practical and theoretical standpoints. Most of the theoretical work so far has focused on the case were the data is sampled from a low-dimensional structure.…

Statistics Theory · Mathematics 2010-11-12 Noureddine El Karoui

Because the cochlear is very small and complex, vibration data of the whole basement membrane are not yet available from existing experiments, To address this question, this work technically adopts the mathematical and biological methods to…

Biological Physics · Physics 2021-01-12 W. Yao , J. Ma , J. Liang , X. Huang

We analytically study proximity and distance properties of various kernels and similarity measures on graphs. This helps to understand the mathematical nature of such measures and can potentially be useful for recommending the adoption of…

Combinatorics · Mathematics 2018-08-17 Konstantin Avrachenkov , Pavel Chebotarev , Dmytro Rubanov

This study addresses the problem of convolutional kernel learning in univariate, multivariate, and multidimensional time series data, which is crucial for interpreting temporal patterns in time series and supporting downstream machine…

Machine Learning · Computer Science 2025-04-17 Xinyu Chen , HanQin Cai , Fuqiang Liu , Jinhua Zhao

Astrophysical images issued from different instruments and/or spectral bands often require to be processed together, either for fitting or comparison purposes. However each image is affected by an instrumental response, also known as PSF,…

Instrumentation and Methods for Astrophysics · Physics 2016-12-07 Alexandre Boucaud , Marco Bocchio , Alain Abergel , François Orieux , Hervé Dole , Mohamed Amine Hadj-Youcef

Future missions such as Solar Orbiter (SO), InterHelioprobe, or Solar Probe aim at approaching the Sun closer than ever before, with on board some high resolution imagers (HRI) having a subsecond cadence and a pixel area of about $(80km)^2$…

Astrophysics · Physics 2015-05-13 Véronique Delouille , Pierre Chainais , Jean-François Hochedez