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Related papers: Diffuse continuum transfer in H II regions

200 papers

Density-density response functions are evaluated for nondegenerate multisubband electron systems in the random-phase approximation for arbitrary wave number and subband index. We consider both quasi-two-dimensional and quasi-one-…

Strongly Correlated Electrons · Physics 2009-10-31 Sviatoslav S. Sokolov , Nelson Studart

Color plays an important role in human visual perception, reflecting the spectrum of objects. However, the existing infrared and visible image fusion methods rarely explore how to handle multi-spectral/channel data directly and achieve high…

Computer Vision and Pattern Recognition · Computer Science 2024-10-28 Jun Yue , Leyuan Fang , Shaobo Xia , Yue Deng , Jiayi Ma

The drift and diffusion of a cloud of ions in a fluid are distorted by an inhomogeneous electric field. If the electric field carries the center of the distribution in a straight line and the field configuration is suitably symmetric, the…

Instrumentation and Detectors · Physics 2009-11-13 R. N. Cahn , J. D. Jackson

The problem of eliminating fast-relaxing variables to obtain an effective drift-diffusion process in position is solved in a uniform and straightforward way for models with velocity a function jointly of position and fast variables. A more…

Statistical Mechanics · Physics 2019-11-13 Paul E. Lammert

A particle with internal unobserved states diffusing in a force field will generally display effective advection-diffusion. The drift velocity is proportional to the mobility averaged over the internal states, or effective mobility, while…

Statistical Mechanics · Physics 2017-10-13 Erik Aurell , Stefano Bo

We describe recent developments in the hybrid atomistic/continuum modelling of dense fluids. We discuss the general implementation of mass, momentum and energy transfers between a region described by molecular dynamics and the neighbouring…

Computational Physics · Physics 2007-05-23 R. Delgado-Buscalioni , P. V. Coveney

This work outlines a diffuse interface method for the study of fracture and fragmentation in ductile metals at high strain-rates in Eulerian finite volume simulations. The work is based on an existing diffuse interface method capable of…

Computational Physics · Physics 2022-10-11 Tim Wallis , Philip T. Barton , Nikolaos Nikiforakis

Multiscale problems are computationally costly to solve by direct simulation because the smallest scales must be represented over a domain determined by the largest scales of the problem. We have developed and analyzed new numerical methods…

Numerical Analysis · Mathematics 2011-11-11 Björn Engquist , Henrik Holst , Olof Runborg

We explore the oscillatory behavior observed in inversion methods applied to large-scale text-to-image diffusion models, with a focus on the "Flux" model. By employing a fixed-point-inspired iterative approach to invert real-world images,…

Computer Vision and Pattern Recognition · Computer Science 2024-11-19 Yan Zheng , Zhenxiao Liang , Xiaoyan Cong , Lanqing guo , Yuehao Wang , Peihao Wang , Zhangyang Wang

We describe the addition of Lyman-alpha resonant line transfer to our dust continuum radiation transfer code SKIRT, verifying our implementation with published results for spherical problems and using some self-designed three-dimensional…

Instrumentation and Methods for Astrophysics · Physics 2021-08-04 Peter Camps , Christoph Behrens , Maarten Baes , Anand Utsav Kapoor , Robert Grand

Global Illumination (GI) is of utmost importance in the field of photo-realistic rendering. However, its computation has always been very complex, especially diffuse GI. State of the art real-time GI methods have limitations of different…

Graphics · Computer Science 2020-07-30 Jinkai Hu , Milo Yip , G. Elias Alonso , Shihao Gu , Xiangjun Tang , Xiaogang Jin

Transport in multiphase flow through porous media plays a central role in many biological, geological, and engineered systems. Here, we use numerical simulations of transport in immiscible two-phase flow to investigate dispersion in…

Fluid Dynamics · Physics 2021-11-29 Joachim Mathiesen , Gaute Linga , Marek Misztal , Francois Renard , Tanguy Le Borgne

Drift-diffusion plasma fluid models are commonly used to simulate electric discharges. Such models can computationally be very efficient if they are combined with explicit time integration. This paper deals with two issues that often arise…

Computational Physics · Physics 2020-02-19 Jannis Teunissen

Diffusion models have shown an impressive ability to model complex data distributions, with several key advantages over GANs, such as stable training, better coverage of the training distribution's modes, and the ability to solve inverse…

Computer Vision and Pattern Recognition · Computer Science 2024-06-12 Yinbo Chen , Oliver Wang , Richard Zhang , Eli Shechtman , Xiaolong Wang , Michael Gharbi

In this paper the use of nonlinear cross-diffu\-sion systems to model image restoration is investigated, theoretically and numerically. In the first case, well-posedness, scale-space properties and long time behaviour are analyzed. From a…

Analysis of PDEs · Mathematics 2017-02-21 A. Araújo , S. Barbeiro , E. Cuesta , A. Durán

We propose a seamless multiscale method which approximates the macroscopic behavior of the passive advection-diffusion equations with steady incompressible velocity fields with multi-spatial scales. The method uses decompositions of the…

Numerical Analysis · Mathematics 2016-06-22 Yoonsang Lee , Bjorn Engquist

Discrete delta functions define the limits of attainable spatial resolution for all imaging systems. Here we construct broad, multi-dimensional discrete functions that replicate closely the action of a Dirac delta function under aperiodic…

Image and Video Processing · Electrical Eng. & Systems 2020-09-01 I. D. Svalbe , D. M. Paganin , T. C. Petersen

Many physical systems of interest involve the close interaction of a flow in a domain with complex, time-varying boundaries. Treatment of boundaries of this nature is cumbersome due to the difficulty in explicitly tracking boundaries that…

Fluid Dynamics · Physics 2025-02-25 Emma M. Boyd , Eric Sandall , Maycon Meier , J. Matt Quinlan , Brandon Runnels

Scientists have observed and studied diffusive waves in contexts as disparate as population genetics and cell signaling. Often, these waves are propagated by discrete entities or agents, such as individual cells in the case of cell…

Pattern Formation and Solitons · Physics 2021-07-21 Paul Dieterle , Ariel Amir

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