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Related papers: Numerical algorithms of the radiative transport eq…

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In this work, we introduce a fast numerical algorithm to solve the time-dependent radiative transport equation (RTE). Our method uses the integral formulation of RTE and applies the treecode algorithm to reduce the computational complexity…

Numerical Analysis · Mathematics 2020-01-29 Hongkai Zhao , Yimin Zhong

Recent work by McClarren & Hauck [29] suggests that the filtered spherical harmonics method represents an efficient, robust, and accurate method for radiation transport, at least in the two-dimensional (2D) case. We extend their work to the…

High Energy Astrophysical Phenomena · Physics 2013-04-16 David Radice , Ernazar Abdikamalov , Luciano Rezzolla , Christian D. Ott

With its roots in kinetic theory, the lattice Boltzmann method (LBM) cannot only be used to solve complex fluid flows but also radiative transport in volume. The present work derives a novel Fresnel boundary scheme for radiative transport…

Computational Physics · Physics 2021-07-21 Albert Mink , Kira Schediwy , Marc Haussmann , Clemens Posten , Hermann Nirschl , Mathias J. Krause

We develop and implement a compressive reconstruction method for tomographic recovery of refractive index distribution for weakly attenuating objects in a microfocus X-ray system. This is achieved through the development of a discretized…

The development of energy selective, photon counting X-ray detectors allows for a wide range of new possibilities in the area of computed tomographic image formation. Under the assumption of perfect energy resolution, here we propose a…

Computer Vision and Pattern Recognition · Computer Science 2015-06-16 Oguz Semerci , Ning Hao , Misha E. Kilmer , Eric L. Miller

We derive new equations using the mixed-frame approach for one- and two-dimensional (axisymmetric) time-dependent radiation transport and the associated couplings with matter. Our formulation is multi-group and multi-angle and includes…

Astrophysics · Physics 2011-02-11 Ivan Hubeny , Adam Burrows

We present the first extension of the special-relativistic Lattice-Boltzmann Method for radiative transport developed by Weih et al. (2020), to solve the radiative-transfer equation in curved spacetimes. The novel approach is based on the…

General Relativity and Quantum Cosmology · Physics 2025-02-26 Tom Olsen , Luciano Rezzolla

Light transport in graded index media follows a curved trajectory determined by the Fermat's principle. Besides the effect of variation of the refractive index on the transport of radiative intensity, the curved ray trajectory will induce…

Classical Physics · Physics 2015-05-30 J. M. Zhao , J. Y. Tan , L. H. Liu

In this paper, we study the mathematical imaging problem of optical diffraction tomography (ODT) for the scenario of a microscopic rigid particle rotating in a trap created, for instance, by acoustic or optical forces. Under the influence…

Linear kinetic transport equations play a critical role in optical tomography, radiative transfer and neutron transport. The fundamental difficulty hampering their efficient and accurate numerical resolution lies in the high dimensionality…

Numerical Analysis · Mathematics 2021-12-07 Zhichao Peng , Yanlai Chen , Yingda Cheng , Fengyan Li

Porous and heterogeneous materials are found in many applications from composites, membranes, chemical reactors, and other engineered materials to biological matter and natural subsurface structures. In this work we propose an integrated…

Computational Physics · Physics 2019-09-15 Gianluca Boccardo , Eleonora Crevacore , Alberto Passalacqua , Matteo Icardi

Radiation transport plays a crucial role in star formation models, as certain questions within this field cannot be accurately addressed without taking it into account. Given the high complexity of the interstellar medium from which stars…

Instrumentation and Methods for Astrophysics · Physics 2024-03-11 Richard Wünsch

We present a ray-tracing technique for radiative transfer modeling of complex three-dimensional (3D) structures which include dense regions of high optical depth like in dense molecular clouds, circumstellar disks, envelopes of evolved…

Astrophysics · Physics 2009-11-11 J. Steinacker , A. Bacmann , Th. Henning

We present a numerical method for handling the resolution of a general transport equation for radiative particles, aimed at physical problems with a general spherical geometry. Having in mind the computational time difficulties encountered…

Computational Physics · Physics 2013-04-16 Silvano Bonazzola , Nicolas Vasset , Bruno Peres

A new group of reduced-order models (ROMs) for nonlinear thermal radiative transfer (TRT) problems is presented. They are formulated by means of the nonlinear projective approach and data compression techniques. The nonlinear projection is…

Numerical Analysis · Mathematics 2024-03-12 Joseph M. Coale , Dmitriy Y. Anistratov

The first numerical solution of the 3-D travel time tomography problem is presented. The globally convergent convexification numerical method is applied.

Numerical Analysis · Mathematics 2022-09-21 Michael V. Klibanova Jingzhi Li , Wenlong Zhang

We propose in this work a fast numerical algorithm for solving the equation of radiative transfer (ERT) in isotropic media. The algorithm has two steps. In the first step, we derive an integral equation for the angularly averaged ERT…

Numerical Analysis · Mathematics 2019-07-09 Kui Ren , Rongting Zhang , Yimin Zhong

We develop a quantum reductive perturbation method (RPM), a generalization of classical RPM widely used in nonlinear wave theory, to derive a simplified model (i.e. quantum nonlinear Schrodinger equation) from fully quantum…

Quantum Physics · Physics 2024-06-13 Ou Yao , Huang Guoxiang

Photoemission orbital tomography provides direct access from laboratory measurements to the real-space molecular orbitals of well-ordered organic semiconductor layers. Specifically, the application of phase retrieval algorithms to…

Materials Science · Physics 2024-04-29 Thi Lan Dinh , G. S. Matthijs Jansen , D. Russell Luke , Wiebke Bennecke , Stefan Mathias

This paper is presented to give numerical solutions of some cases of nonlinear wave-like equations with variable coefficients by using Reduced Differential Transform Method (RDTM). RDTM can be applied most of the physical, engineering,…

Numerical Analysis · Mathematics 2014-07-21 Murat Gubes , Yildiray Keskin , Galip Oturanc