Results 1 to 10 of about 42,713 (266)

Topological invariants for holographic semimetals

Journal of High Energy Physics, 2018
We study the behavior of fermion spectral functions for the holographic topological Weyl and nodal line semimetals. We calculate the topological invariants from the Green functions of both holographic semimetals using the topological Hamiltonian method ...
Yan Liu, Ya-Wen Sun
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Spectral-Nodal Deterministic Methodology for Neutron Shielding Calculations using the X, Y - geometry Multigroup Transport Equation in the Discrete Ordinates Formulation

Vetor, 2021
In this work, we present the most recent numerical results in a nodal approach, which resulted in the development of a new numerical spectral nodal method, based on the spectral analysis of the multigroup, isotropic scattering neutron transport equations
Amaury Munoz Oliva, Hermes Alves Filho
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The adjoint transport problem applied to estimate neutral particle leakage in the discrete ordinates formulations

Brazilian Journal of Radiation Sciences, 2022
In source–detector problems, neutron leakage is a quantity of interest that could lead to improve shielding structures, thus reducing the dose received by humans.
Jesús Pérez Curbelo, Ricardo Carvalho de Barros   +1 more
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On the spectral Green’s function-constant nodal method for fixed-source SN problems in X,Y-geometry with arbitrary L’th-order anisotropic scattering

Brazilian Journal of Radiation Sciences, 2021
Presented here is an extension of the spectral Green’s function-constant nodal (SGF-CN) method for the numerical solution of energy multigroup, fixed-source, discrete ordinates (SN) problems in X, Y-geometry with arbitrary L’th-order of scattering ...
Welton Menezes, Gustavo Alvarez, Ricardo Barros   +2 more
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Spectral Nodal Methodology for Multigroup Slab-Geometry Discrete Ordinates Neutron Transport Problems with Linearly Anisotropic Scattering

Brazilian Journal of Radiation Sciences, 2021
In this paper, we propose a numerical methodology for the development of a method of the spectral nodal class that generates numerical solutions free from spatial truncation errors.
Amaury Muñoz Oliva, Hermes Alves Filho, Davi José Martins e Silva, Carlos Rafael García Hernández   +3 more
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Analysis of High-order Approximations by Spectral Interpolation Applied to One- and Two-dimensional Finite Element Method [PDF]

Journal of Applied and Computational Mechanics, 2020
The implementation of high-order (spectral) approximations associated with FEM is an approach to overcome the difficulties encountered in the numerical analysis of complex problems.
Luís Philipe Ribeiro Almeida, Hilton Marques Souza Santana, Fabio Carlos Da Rocha   +2 more
doaj   +1 more source

The modified spectral deterministic method applied to fixed–source discrete ordinates problems in X,Y–geometry

Brazilian Journal of Radiation Sciences, 2021
A new approach for the application of the coarse–mesh Modified Spectral Deterministic method to numerically solve the two–dimensional neutron transport equation in the discrete ordinates (Sn) formulation is presented in this work.
Jesús Pérez Curbelo, Rafael Barbosa Libotte, Amaury Muñoz Oliva, Ricardo Carvalho Barros, Hermes Alves Filho   +4 more
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Quasi-3-D spectral wavelet method for a thermal quench simulation

Journal of Mathematics in Industry, 2021
The finite element method is widely used in simulations of various fields. However, when considering domains whose extent differs strongly in different spatial directions a finite element simulation becomes computationally very expensive due to the large
Jonas Bundschuh, Laura A. M. D’Angelo, Herbert De Gersem   +2 more
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Spectral Element-Based Multi-Physical Modeling Framework for Axisymmetric Wireless Power Transfer Systems

Energies, 2022
This paper concerns a multi-physical modeling framework based on the spectral element method (SEM) for axisymmetric wireless power transfer systems. The modeling framework consists of an electromagnetic and a thermal model.
Koen Bastiaens, Dave C. J. Krop, Elena A. Lomonova   +2 more
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A high-order staggered finite-element vertical discretization for non-hydrostatic atmospheric models [PDF]

Geoscientific Model Development, 2016
Atmospheric modeling systems require economical methods to solve the non-hydrostatic Euler equations. Two major differences between hydrostatic models and a full non-hydrostatic description lies in the vertical velocity tendency and numerical stiffness ...
J. E. Guerra, P. A. Ullrich
doaj   +1 more source