Now showing items 37-56 of 189

• #### Dimensionally adaptive hp-finite element simulation and inversion of 2D magnetotelluric measurements ﻿

(Journal of Computational Science, 2016-09-01)
Magnetotelluric (MT) problems often contain different subdomains where the conductivity of the media depends upon one, two, or three spatial variables. Traditionally, when a MT problem incorporates a three-dimensional (3D) ...
• #### Direct FEM large scale computation of turbulent multiphase flow in urban water systems and marine energy ﻿

(Proceesings of ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering, 2016-11-30)
High-Reynolds number turbulent incompressible multiphase flow represents a large class of engineering problems of key relevance to society. Here we describe our work on modeling two such problems: 1. The Consorcio de Aguas ...
• #### Direct finite element simulation of turbulent flow for marine based renewable energy ﻿

(Companion paper to F. Wendt, et. al. International energy agency ocean energy systems task 10 wave energy converter modeling verification and validation. In 12th European Wave and Tidal Energy Conference, 2017., 2017)
In this article we present a computational framework for simulation of turbulent flow in marine based renewable energy applications. In particular, we focus on floating structures and rotating turbines. This work is an ...
• #### Direct solvers performance on h-adapted grids ﻿

(Computers and Mathematics with Applications, 2015-12-31)
We analyse the performance of direct solvers when applied to a system of linear equations arising from an $h$-adapted, $C^0$ finite element space. Theoretical estimates are derived for typical $h$-refinement patterns arising ...
• #### Discontinuous high-order finite-volume/finite-element method for inviscid compressible flows ﻿

(53rd AIAA Aerospace Sciences Meeting (2015), 2015-12-31)
The discontinuous, hybrid control-volume/finite-element method merges the desirable conservative properties and intuitive physical formulation of the finite-volume technique, with the capability of local arbitrary high-order ...
• #### Discrete maximum principles for nonlinear parabolic PDE systems ﻿

(IMA Journal of Numerical Analysis, 2012-12-31)
Discrete maximum principles (DMPs) are established for finite element approximations of systems of nonlinear parabolic partial differential equations with mixed boundary and interface conditions. The results are based on ...
• #### Discrete nonnegativity for nonlinear cooperative parabolic PDE systems with non-monotone coupling ﻿

(Mathematics and Computers in Simulation, 2013-12-31)
Discrete nonnegativity principles are established for finite element approximations of nonlinear parabolic PDE systems with mixed boundary conditions. Previous results of the authors are extended such that diagonal dominance ...
• #### Dispersion-minimizing quadrature rules for $C^1$ quadratic isogeometric analysis ﻿

(Computer Methods in Applied Mechanics and Engineering, 2017-09-20)
We develop quadrature rules for the isogeometric analysis of wave propagation and structural vibrations that minimize the discrete dispersion error of the approximation. The rules are optimal in the sense that they only ...
• #### Editors' preface for the topical issue "Advances in Numerical Analysis and Numerical Linear Algebra" ﻿

(Central European Journal of Mathematics, 2012-12-31)
[No abstract available]
• #### Editors' preface for the topical issue "Numerical Methods for Large-Scale Scientific Computing, I" ﻿

(Central European Journal of Mathematics, 2013-12-31)
[No abstract available]
• #### Editors' preface for the topical issue "Numerical Methods for Large-Scale Scientific Computing, II" ﻿

(Central European Journal of Mathematics, 2013-12-31)
[No abstract available]
• #### Efficient mass and stiffness matrix assembly via weighted Gaussian quadrature rules for B-splines ﻿

(Journal of Computational and Applied Mathematics, 2019-12-14)
Calabr{\`o} et al. [10] changed the paradigm of the mass and stiffness computation from the traditional element-wise assembly to a row-wise concept, showing that the latter one offers integration that may be orders of ...
• #### Efficient quadrature rules for subdivision surfaces in isogeometric analysis ﻿

(Computer Methods in Applied Mechanics and Engineering, 2018-10)
We introduce a new approach to numerical quadrature on geometries defined by subdivision surfaces based on quad meshes in the context of isogeometric analysis. Starting with a sparse control mesh, the subdivision process ...
• #### Efficient rigorous numerics for higher-dimensional PDEs via one-dimensional estimates ﻿

(SIAM Journal on Numerical Analysis, 2013-12-31)
We present an efficient rigorous computational method which is an extension of the work Analytic Estimates and Rigorous Continuation for Equilibria of Higher-Dimensional PDEs (M. Gameiro and J.-P. Lessard, J. Differential ...
• #### Efficient Rotating Frame Simulation in Turbomachinery ﻿

(Proceedings of ASME Turbo Expo 2014: Turbine Technical Conference and Exposition; Dusseldorf, Germany, June 16-20 2014", 2014-12-31)
This paper deals with the simulation of steady flows in tur- bomachinery. Two approaches are proposed, the first one is the classical multiple-rotating frame method (MRF) by multi- zone approach where the different zones ...
• #### Energy-norm-based and goal-oriented automatic hp adaptivity for electromagnetics: Application to waveguide Discontinuities ﻿

(IEEE Transactions on Microwave Theory and Techniques, 2008-12-31)
The finite-element method (FEM) enables the use of adapted meshes. The simultaneous combination of h (local variations in element size) and p (local variations in the polynomial order of approximation) refinements, i.e., ...
• #### Enhanced variational image dehazing ﻿

(SIAM Journal on Imaging Sciences, 2015-12-31)
Images obtained under adverse weather conditions, such as haze or fog, typically exhibit low contrast and faded colors, which may severely limit the visibility within the scene. Unveiling the image structure under the haze ...
• #### Existence of secondary bifurcations or isolas for PDEs ﻿

(Nonlinear Analysis, Theory, Methods and Applications, 2011-12-31)
In this paper, we introduce a method to conclude about the existence of secondary bifurcations or isolas of steady state solutions for parameter dependent nonlinear partial differential equations. The technique combines ...
• #### Explicit-in-Time Goal-Oriented Adaptivity ﻿

(Computer Methods in Applied Mechanics and Engineering, 2019-04-15)
Goal-oriented adaptivity is a powerful tool to accurately approximate physically relevant solution features for partial differential equations. In time dependent problems, we seek to represent the error in the quantity of ...
• #### Explicit-in-Time Variational Formulations for Goal-Oriented Adaptivity ﻿

(2019-10)
Goal-Oriented Adaptivity (GOA) is a powerful tool to accurately approximate physically relevant features of the solution of Partial Differential Equations (PDEs). It delivers optimal grids to solve challenging engineering ...