English
Related papers

Related papers: Ray Effect Mitigation for the Discrete Ordinates M…

200 papers

In this paper we introduce a method for solving linear and nonlinear scattering problems for wave equations using a new hybrid approach. This new approach consists of a reformulation of the governing equations into a form that can be solved…

Numerical Analysis · Mathematics 2018-07-04 Aihua Lin , Anastasiia Kuzmina , Per Kristen Jakobsen

An operator-splitting finite element scheme for the time-dependent, high-dimensional radiative transfer equation is presented in this paper. The streamline upwind Petrov-Galerkin finite element method and discontinuous Galerkin finite…

Numerical Analysis · Mathematics 2022-03-22 Sashikumaar Ganesan , Maneesh Kumar Singh

We develop a high-order, explicit method for acoustic scattering in three space dimensions based on a combined-field time-domain integral equation. The spatial discretization, of Nystr\"om type, uses Gaussian quadrature on panels combined…

Numerical Analysis · Mathematics 2020-01-29 Alex H. Barnett , Leslie Greengard , Tom Hagstrom

Spontaneous Raman scattering (SpRS) is a weak non-linear effect, particularly relevant to classical-quantum coexistence transmission and sensing applications. In classical transmission, the relevant Raman effect is stimulated Raman…

The scattering of light impacts sensing and communication technologies throughout the electromagnetic spectrum. Overcoming the effects of time-varying scattering media is particularly challenging. In this article we introduce a new way to…

The approximate nature of radiative transfer equation (RTE) leads to a bunch of considerations on the effect of "dependent scattering" in random media, especially particulate media composed of discrete scatterers, in the last a few decades,…

Mesoscale and Nanoscale Physics · Physics 2018-05-08 B. X. Wang , C. Y. Zhao

The discrete-dipole approximation (DDA) is a powerful method for calculating absorption and scattering by targets that have sizes smaller than or comparable to the wavelength of the incident radiation. We present a new prescription -- the…

Astrophysics · Physics 2015-06-24 Matthew J. Collinge , B. T. Draine

This paper studies the shallow Ritz method for solving the one-dimensional diffusion problem. It is shown that the shallow Ritz method improves the order of approximation dramatically for non-smooth problems. To realize this optimal or…

Numerical Analysis · Mathematics 2025-11-25 Zhiqiang Cai , Anastassia Doktorova , Robert D. Falgout , César Herrera

In this paper, we consider the initial boundary value problem of the two dimensional multi-term time fractional mixed diffusion and diffusion-wave equations. An alternating direction implicit (ADI) spectral method is developed based on…

Numerical Analysis · Mathematics 2018-09-03 Zeting Liu , Fawang Liu , Fanhai Zeng

Diffuse scattering is a rich source of information about disorder in crystalline materials, which can be modelled using atomistic techniques such as Monte Carlo and molecular dynamics simulations. Modern X-ray and neutron scattering…

Materials Science · Physics 2018-12-21 Joseph A. M. Paddison

We consider the multidimensional space-fractional diffusion equations with spatially varying diffusivity and fractional order. Significant computational challenges are encountered when solving these equations due both to the kernel…

Numerical Analysis · Mathematics 2021-08-31 Hasnaa Alzahrani , George Turkiyyah , Omar Knio , David Keyes

A systematic digital-discrete method for obtaining continuous functions with smoothness to a certain order (C^(n)) from sample data is designed. This method is based on gradually varied functions and the classical finite difference method.…

Numerical Analysis · Mathematics 2010-10-19 Li Chen

We consider a novel way of discretizing wave scattering problems using the general formalism of convolution quadrature, but instead of reducing the timestep size ($h$-method), we achieve accuracy by increasing the order of the method…

Numerical Analysis · Mathematics 2024-10-25 Alexander Rieder

We calculate the differential, total, and transport cross-sections for scattering of two-dimensional massless Dirac electrons by a circular barrier. For scatterer of a small radius, the cross-sections are dominated by quantum effects such…

Mesoscale and Nanoscale Physics · Physics 2014-12-02 Jhih-Sheng Wu , Michael M. Fogler

We develop a unified scattering approach to dynamical Casimir problems which can be applied to both accelerating boundaries, as well as dispersive objects in relative motion. A general (trace) formula is derived for the radiation from…

Quantum Physics · Physics 2013-01-14 Mohammad F. Maghrebi , Ramin Golestanian , Mehran Kardar

A spatial second-order scheme for the nonlinear radiative transfer equations is introduced in this paper. The discretization scheme is based on the filtered spherical harmonics ($FP_N$) method for the angular variable and the unified gas…

Numerical Analysis · Mathematics 2023-10-09 Xiaojing Xu , Song Jiang , Wenjun Sun

Background: Path integrals are a powerful tool for solving problems in quantum theory that are not amenable to a treatment by perturbation theory. Most path integral computations require an analytic continuation to imaginary time. While…

Nuclear Theory · Physics 2020-07-01 W. N. Polyzou , Ekaterina Nathanson

Electrical Impedance Tomography gives rise to the severely ill-posed Calder\'on problem of determining the electrical conductivity distribution in a bounded domain from knowledge of the associated Dirichlet-to-Neumann map for the governing…

Analysis of PDEs · Mathematics 2022-01-26 Kim Knudsen , Aksel K. Rasmussen

The effects of thermal diffuse scattering on the transmission and eventual diffraction of highly accelerated electrons are investigated with a method that incorporates the frozen phonon approximation to the exact numerical solution of the…

Computational Physics · Physics 2018-01-22 S. Rudinsky , A. S. Sanz , R. Gauvin

Discrete ordinate ($S_N$) and filtered spherical harmonics ($FP_N$) based schemes have been proven to be robust and accurate in solving the Boltzmann transport equation but they have their own strengths and weaknesses in different physical…

Numerical Analysis · Mathematics 2023-08-09 Maitraya K Bhattacharyya , David Radice