Browsing Computational Mathematics (CM) by Title
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Fast 2.5D Finite Element Simulations of Borehole Resistivity Measurements
(Computational Geosciences, 20180529)We develop a rapid 2.5dimensional (2.5D) finite element method for simulation of borehole resistivity measurements in transversely isotropic (TI) media. The method combines arbitrary highorder $H^1$  and $H$ (curl)conforming ... 
Fast inversion of loggingwhiledrilling resistivity measurements acquired in multiple wells
(Geophysics, 201610)This paper introduces a new method for the fast inversion of borehole resistivity measurements acquired in multiple wells using loggingwhiledrilling (LWD) instruments. There are two key novel contributions. First, we ... 
Fast Onedimensional Finite Element Approximation of Geophysical Measurements
(2018)There exist a wide variety of geophysical prospection methods. In this work, we focus on resistivity methods. We categorize these resistivity prospection methods according to their acquisition location as (a) on the surface, ... 
Fast simulation of throughcasing resistivity measurements using semianalytical asymptotic models. Part 1: Accuracy study
(EAGE Workshop on High Performance Computing for Upstream 2014, 20141231)When trying to obtain a better characterization of the Earth's subsurface, it is common to use borehole throughcasing resistivity measurements. It is also common for the wells to be surrounded by a metal casing to protect ... 
A FEniCSHPC framework for multicompartment BlochTorrey models
(Proceesings of ECCOMAS Congress 2016 VII European Congress on Computational Methods in Applied Sciences and Engineering, 20161130)In diffusion nuclear magnetic resonance (NMR) and diffusion magnetic resonance imaging (MRI), the multicompartment BlochTorrey equation plays an important role in probing the diffusion characteristics from a nanometer ... 
FEniCSHPC: Automated predictive highperformance finite element computing with applications in aerodynamics
(Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 20160101)Developing multiphysics finite element methods (FEM) and scalable HPC implementations can be very challenging in terms of software complexity and performance, even more so with the addition of goaloriented adaptive mesh ... 
Finite element approximation of electromagnetic fields using nonfitting meshes for Geophysics
(SIAM Journal on Numerical Analysis, 201807)We analyze the use of nonfitting meshes for simulating the propagation of electromagnetic waves inside the earth with applications to borehole logging. We avoid the use of parameter homogenization and employ standard edge ... 
Finite Element Simulations of LoggingWhileDrilling and ExtraDeep Azimuthal Resistivity Measurements using NonFitting Grids
(Computational Geosciences, 20180427)We propose a discretization technique using nonfitting grids to simulate magnetic fieldbased resistivity logging measurements. Nonfitting grids are convenient because they are simpler to generate and handle than fitting ... 
Finite Element Simulations of Twophase Flow and Floating Bodies Using FEniCSHPC
(13th World Congress in Computational Mechanics WCCM, New York, USA, 201807)We present a variational multiscale stabilized finite element method to solve the variable density incompressible NavierStokes equations for the simulation of twophase flow. We introduce a levelset method based on the ... 
ForwardinTime GoalOriented Adaptivity
(International Journal for Numerical Methods in Engineering, 201903)In goaloriented adaptive algorithms for partial differential equations, we adapt the finite element mesh in order to reduce the error of the solution in some quantity of interest. In timedependent problems, this adaptive ... 
Fourier finite element modeling of light emission in waveguides: 2.5dimensional FEM approach
(Optics Express, 20151231)We present a Fourier finite element modeling of light emission of dipolar emitters coupled to infinitely long waveguides. Due to the translational symmetry, the threedimensional (3D) coupled waveguideemitter system can ... 
Fractional Laguerre spectral methods and their applications to fractional differential equations on unbounded domain
(International Journal of Computer Mathematics, 20151231)In this article, we first introduce a singular fractional SturmLiouville problem (SFSLP) on unbounded domain. The associated fractional differential operator is both Weyl and Caputo type. The properties of spectral data ... 
Framework for adaptive fluidstructure interaction with industrial applications
(International Journal of Materials Engineering Innovation, 20131231)We present developments in the UnicornHPC framework for unified continuum mechanics, enabling adaptive finite element computation of fluidstructure interaction, and an overview of the larger FEniCSHPC framework for ... 
Fusionbased variational image dehazing
(IEEE Signal Processing Letters, 20170201)We propose a novel imagedehazing technique based on the minimization of two energy functionals and a fusion scheme to combine the output of both optimizations. The proposed fusionbased variational imagedehazing (FVID) ... 
GaussGalerkin quadrature rules for quadratic and cubic spline spaces and their application to isogeometric analysis
(ComputerAided Design, 20160701)We introduce Gaussian quadrature rules for spline spaces that are frequently used in Galerkin discretizations to build mass and stiffness matrices. By definition, these spaces are of even degrees. The optimal quadrature ... 
Gaussian quadrature for $C^1$ cubic CloughTocher macrotriangles
(Journal of Computational and Applied Mathematics, 20181031)A numerical integration rule for multivariate cubic polynomials over ndimensional simplices was designed by Hammer and Stroud [14]. The quadrature rule requires n + 2 quadrature points: the barycentre of the simplex and ... 
Gaussian quadrature rules for $C^1$ quintic splines with uniform knot vectors
(Journal of Computational and Applied Mathematics, 20170322)We provide explicit quadrature rules for spaces of $C^1$ quintic splines with uniform knot sequences over finite domains. The quadrature nodes and weights are derived via an explicit recursion that avoids numerical solvers. ... 
Generalization of the Pythagorean Eigenvalue Error Theorem and its Application to Isogeometric Analysis
(Numerical Methods for PDEs, 20181013)This chapter studies the effect of the quadrature on the isogeometric analysis of the wave propagation and structural vibration problems. The dispersion error of the isogeometric elements is minimized by optimally blending ... 
Generalization of the Zlámal condition for simplicial finite elements in ℝ d
(Applications of Mathematics, 20111231)The famous Zlámal's minimum angle condition has been widely used for construction of a regular family of triangulations (containing nondegenerating triangles) as well as in convergence proofs for the finite element method ... 
GoalOriented Adaptivity using Unconventional Error Representations
(201709)In GoalOriented Adaptivity (GOA), the error in a Quantity of Interest (QoI) is represented using global error functions of the direct and adjoint problems. This error representation is subsequently bounded above by ...