English
Related papers

Related papers: Discrete diffusion Lyman-alpha radiative transfer

200 papers

We developed a Monte Carlo code that describes the resonant Lyman alpha line transfer in an optically thick, dusty, and static medium. The code was tested against the analytic formula derived by Neufeld (1990). We explain the line transfer…

Astrophysics · Physics 2016-08-30 Sang-Hyeon Ahn , Hee-Won Lee , Hyung-Mok Lee

Discrete cosine transform (DCT) and other Fourier-related transforms have broad applications in scientific computing. However, off-the-shelf high-performance multi-dimensional DCT (MD DCT) libraries are not readily available in parallel…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-10-05 Zixuan Jiang , Jiaqi Gu , David Z. Pan

Molecular communication (MC) allows nanomachines to communicate and cooperate with each other in a fluid environment. The diffusion-based MC is popular but is easily constrained by the transmit distance due to the severe attenuation of…

Information Theory · Computer Science 2021-04-28 Shuo Yuan , Jiaxing Wang , Mugen Peng

We study signal processing tasks in which the signal is mapped via some generalized time-frequency transform to a higher dimensional time-frequency space, processed there, and synthesized to an output signal. We show how to approximate such…

Numerical Analysis · Mathematics 2021-09-07 Ron Levie , Haim Avron , Gitta Kutyniok

We discuss Monte-Carlo techniques for addressing the 3-dimensional time-dependent radiative transfer problem in rapidly expanding supernova atmospheres. The transfer code SEDONA has been developed to calculate the lightcurves, spectra, and…

Astrophysics · Physics 2008-11-26 Daniel Kasen , R. C. Thomas , Peter Nugent

Monte Carlo methods are state-of-the-art when it comes to dosimetric computations in radiotherapy. However, the execution time of these methods suffers in high-collisional regimes. We address this problem by introducing a kinetic-diffusion…

Quantitative Methods · Quantitative Biology 2025-08-22 Klaas Willems , Vince Maes , Zhirui Tang , Giovanni Samaey

A novel hybrid Monte Carlo transport scheme is demonstrated in a scene with solar illumination, scattering and absorbing 2D atmosphere, a textured reflecting mountain, and a small detector located in the sky (mounted on a satellite or a…

Mathematical Physics · Physics 2015-05-28 Guillaume Bal , Anthony Davis , Ian Langmore

Monte Carlo dropout may effectively capture model uncertainty in deep learning, where a measure of uncertainty is obtained by using multiple instances of dropout at test time. However, Monte Carlo dropout is applied across the whole network…

Signal Processing · Electrical Eng. & Systems 2020-02-03 Liangping Ma , John Kaewell

Microscopic processes on surfaces such as adsorption, desorption, diffusion and reaction of interacting particles can be simulated using kinetic Monte Carlo (kMC) algorithms. Even though kMC methods are accurate, they are computationally…

Mathematical Physics · Physics 2013-12-24 Yannis Pantazis , Markos Katsoulakis

Can Monte Carlo (MC) solvers be directly used in gradient-based methods for PDE-constrained optimization problems? In these problems, a gradient of the loss function is typically presented as a product of two PDE solutions, one for the…

Numerical Analysis · Mathematics 2022-09-27 Qin Li , Li Wang , Yunan Yang

We present a novel Lyman alpha (Ly$\alpha$) radiative transfer code, SEURAT, where line scatterings are solved adaptively with the resolution of the smoothed particle hydrodynamics (SPH). The radiative transfer method implemented in SEURAT…

Instrumentation and Methods for Astrophysics · Physics 2018-01-30 Makito Abe , Hiroyuki Suzuki , Kenji Hasegawa , Benoit Semelin , Hidenobu Yajima , Masayuki Umemura

Ray tracing algorithms, that can simulate multipath radio propagation in presence of geometric obstacles such as buildings, objects or vehicles, are becoming quite popular, due to the increasing availability of digital environment databases…

Signal Processing · Electrical Eng. & Systems 2023-06-14 Denis Bilibashi , Enrico M. Vitucci , Vittorio Degli-Esposti

We consider an alternative to the Monte Carlo method for dust continuous radiative transfer simulations: the Quasi-Monte Carlo method. We briefly discuss what it is, its history, and possible implementations. We compare the Monte Carlo…

Solar and Stellar Astrophysics · Physics 2024-06-25 S. G. Shulman

An algorithm for creating synthetic telescope images of Smoothed Particle Hydrodynamics (SPH) density fields is presented, which utilises the adaptive nature of the SPH formalism in full. The imaging process uses Monte Carlo Radiative…

Earth and Planetary Astrophysics · Physics 2015-05-18 Duncan Forgan , Ken Rice

Radiative transfer simulation is an important tool that allows us to generate synthetic images of various astrophysical objects. In the case of complex three-dimensional geometries, a Monte Carlo-based method that simulates photon packages…

Instrumentation and Methods for Astrophysics · Physics 2021-01-27 A. Krieger , S. Wolf

Diffusion models have demonstrated significant potential in producing high-quality images in medical image translation to aid disease diagnosis, localization, and treatment. Nevertheless, current diffusion models have limited success in…

Image and Video Processing · Electrical Eng. & Systems 2024-11-26 Yunxiang Li , Hua-Chieh Shao , Xiaoxue Qian , You Zhang

Radiative transfer modelling is part of many astrophysical simulations and is used to make synthetic observations and to assist analysis of observations. We concentrate on the modelling of the radio lines emitted by the interstellar medium.…

Instrumentation and Methods for Astrophysics · Physics 2021-01-04 M. Juvela

Anomalous radiative transfer (ART) theory is a generalization of classical radiative transfer theory. The present tutorial wants to show how Monte Carlo (MC) codes describing photons transport in anomalous media can be implemented. It is…

Computational Physics · Physics 2022-06-02 Tiziano Binzoni , Fabizio Martelli

Discrete diffusion models offer a promising alternative to autoregressive generation through parallel decoding, but they suffer from a sampling wall: once categorical sampling occurs, rich distributional information collapses into one-hot…

Machine Learning · Computer Science 2026-05-14 Mingyu Jo , Jaesik Yoon , Justin Deschenaux , Caglar Gulcehre , Sungjin Ahn

This paper is part of a series investigating the observational appearance of planets accreting from their nascent protoplanetary disk (PPD). We evaluate the differences between gas temperature distributions determined in our radiation…

Earth and Planetary Astrophysics · Physics 2025-02-06 Anton Krieger , Hubert Klahr , Julio David Melon Fuksman , Sebastian Wolf