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Related papers: Radiative transfer on hierarchial grids

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We solved the radiative transfer and statistical equilibrium equations in a two-dimensional cross-section of a cylindrical structure oriented horizontally and lying above the solar surface. The cylinder is filled with a mixture of hydrogen…

Solar and Stellar Astrophysics · Physics 2016-03-02 N. Labrosse , A. S. Rodger

Faced with increasing penetration of distributed energy resources and fast development of distribution grid energy management, topology identification of distribution grid becomes an important and fundamental task. As the underlying grid…

Systems and Control · Electrical Eng. & Systems 2025-07-24 Yueyao Xu , Yize Chen

We develop a transfer matrix formalism for four-flux radiative transfer models, which is ideally suited for studying transport through multiple scattering layers. The model, derived for spherical particles within the diffusion…

Optics · Physics 2018-05-23 Brian Slovick , Zachary Flom , Lucas Zipp , Srini Krishnamurthy

We have developed a three-dimensional radiative transfer method designed specifically for use with parallel adaptive mesh refinement hydrodynamics codes. This new algorithm, which we call hybrid characteristics, introduces a novel form of…

Astrophysics · Physics 2009-11-11 Erik-Jan Rijkhorst , Tomasz Plewa , Anshu Dubey , Garrelt Mellema

Deep learning has become a promising approach for automated medical diagnoses. When medical data samples are limited, collaboration among multiple institutions is necessary to achieve high algorithm performance. However, sharing patient…

Computer Vision and Pattern Recognition · Computer Science 2017-09-19 Ken Chang , Niranjan Balachandar , Carson K Lam , Darvin Yi , James M Brown , Andrew Beers , Bruce R Rosen , Daniel L Rubin , Jayashree Kalpathy-Cramer

Incoherent dedispersion is a computationally intensive problem that appears frequently in pulsar and transient astronomy. For current and future transient pipelines, dedispersion can dominate the total execution time, meaning its…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 Benjamin R. Barsdell , Matthew Bailes , David G. Barnes , Christopher J. Fluke

Downscaling is essential for generating the high-resolution climate data needed for local planning, but traditional methods remain computationally demanding. Recent years have seen impressive results from AI downscaling models, particularly…

Computer Vision and Pattern Recognition · Computer Science 2025-06-27 Declan J. Curran , Sanaa Hobeichi , Hira Saleem , Hao Xue , Flora D. Salim

We present the results of a three-dimensional Monte Carlo radiative transfer code for starless molecular cloud cores heated by an external isotropic or non-isotropic interstellar radiation field. The code computes the dust temperature…

Astrophysics · Physics 2009-11-10 J. Goncalves , D. Galli , M. Walmsley

The improvement in observational facilities requires refining the modelling of the geometrical structures of astrophysical objects. Nevertheless, for complex problems such as line overlap in molecules showing hyperfine structure, a detailed…

Astrophysics · Physics 2015-03-13 F. Daniel , J. Cernicharo

In a recent article the authors showed that the radiative Transfer equations with multiple frequencies and scattering can be formulated as a nonlinear integral system. In the present article, the formulation is extended to handle reflective…

Numerical Analysis · Mathematics 2023-06-12 Olivier Pironneau , Pierre-Henri Tournier

Simple yet accurate results for radiative transfer in layered media with discontinuous refractive index are obtained by the method of K-integrals, originally developed for neutron transport analysis. These are certain weighted integrals…

Optics · Physics 2016-01-05 Adrian C Selden

Ray-tracing (RT) has become central to site-specific electromagnetic propagation modeling in dynamic complex environments. Yet its computational burden grows sharply as high-fidelity digital twins of these environments scale to millions of…

Signal Processing · Electrical Eng. & Systems 2026-05-19 Giacomo Melloni , Enrico M. Vitucci , Vittorio Degli Esposti , Samuel Berweger , Jack Chuang , Camillo Gentile , Nada Golmie

Modelling of stellar radiative intensities in various spectral pass-bands plays an important role in stellar physics. At the same time the direct calculations of the high-resolution spectrum and then integrating it over the given spectral…

Solar and Stellar Astrophysics · Physics 2021-06-30 L. S. Anusha , A. I. Shapiro , V. Witzke , M. Cernetic , S. K. Solanki , L. Gizon

We evaluate an efficient overset grid method for two-dimensional and three-dimensional particulate flows for small numbers of particles at finite Reynolds number. The rigid particles are discretised using moving overset grids overlaid on a…

Computational Physics · Physics 2017-05-24 A. R. Koblitz , S. Lovett , N. Nikiforakis , W. D. Henshaw

Recent approaches to distributed model fitting rely heavily on consensus ADMM, where each node solves small sub-problems using only local data. We propose iterative methods that solve {\em global} sub-problems over an entire distributed…

Distributed, Parallel, and Cluster Computing · Computer Science 2015-04-10 Tom Goldstein , Gavin Taylor , Kawika Barabin , Kent Sayre

A serious concern for semi-analytical galaxy formation models, aiming to simulate multi-wavelength surveys and to thoroughly explore the model parameter space, is the extremely time consuming numerical solution of the radiative transfer of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Laura Silva , Fabio Fontanot , Gian Luigi Granato

Context. Three-dimensional non-local thermodynamical equilibrium (NLTE) radiative transfer calculations are a fundamental tool for a detailed spectral analysis in stellar atmospheres, but require vast amounts of computer power. This…

Solar and Stellar Astrophysics · Physics 2023-07-12 Elias R. Udnæs , Tiago M. D. Pereira

We introduce a novel diffusion-based spectral algorithm to tackle regression analysis on high-dimensional data, particularly data embedded within lower-dimensional manifolds. Traditional spectral algorithms often fall short in such…

Machine Learning · Statistics 2024-10-21 Weichun Xia , Jiaxin Jiang , Lei Shi

Diffusion-based generative methods have proven effective in modeling trajectories with offline datasets. However, they often face computational challenges and can falter in generalization, especially in capturing temporal abstractions for…

Machine Learning · Computer Science 2024-01-08 Chang Chen , Fei Deng , Kenji Kawaguchi , Caglar Gulcehre , Sungjin Ahn

Deep learning-based super-resolution (SR) methods often perform pixel-wise computations uniformly across entire images, even in homogeneous regions where high-resolution refinement is redundant. We propose the Quadtree Diffusion Model…

Computer Vision and Pattern Recognition · Computer Science 2025-11-18 Donglin Yang , Paul Vicol , Xiaojuan Qi , Renjie Liao , Xiaofan Zhang