Computational Mathematics (CM)

Towards HPC-Embedded Case Study: Kalray and Message-Passing on NoC

Valero-Lara P.; Krishnasamy E.; Jansson J. (Scalable Computing, 2017)

Today one of the most important challenges in HPC is the development of computers with a low power consumption. In this context, recently, new embedded many-core systems have emerged. One of them is Kalray. Unlike other ...

New Simplified Algorithm for the Multiple Rotating Frame Approach in Computational Fluid Dynamics

Remaki L.; Ramezani A.; Blanco J. M.; Garcia I. (Journal of Fluids Engineering, 2017-06-02)

This paper deals with rotating effects simulation of steady flows in turbomachinery. To take into account the rotating nature of the flow, the frozen rotor approach is one of the widely used approaches. This technique, ...

Necking in 2D incompressible polyconvex materials: theoretical framework and numerical simulations

Mora-Corral C.; Strugaru M. (Quarterly Journal of Mechanics and Applied Mathematics, 2017-06-15)

We show examples of 2D incompressible isotropic homogeneous hyperelastic materials with a poly-convex stored-energy function that present necking. The construction of the stored-energy function of amaterial satisfying all ...

Fusion-based variational image dehazing

Galdran A.; Vazquez-Corral J.; Pardo D.; Bertalmio M. (IEEE Signal Processing Letters, 2017-02-01)

We propose a novel image-dehazing technique based on the minimization of two energy functionals and a fusion scheme to combine the output of both optimizations. The proposed fusion-based variational image-dehazing (FVID) ...

Gaussian quadrature rules for $C^1$ quintic splines with uniform knot vectors

Bartoň M.; Ait-Haddou R.; Calo V. (Journal of Computational and Applied Mathematics, 2017-03-22)

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. ...

Towards optimal advection using stretch-maximizing stream surfaces

Bartoň M.; Kosinka J. (Computer Aided Geometric Design, 2017-03-01)

We investigate a class of stream surfaces that expand in time as much as possible. Given a vector field, we look for seed curves that locally propagate in time in a stretch-maximizing manner, i.e., curves that infinitesimally ...

Sensitivity study of borehole-to-surface and crosswell electromagnetic measurements acquired with energized steel casing to water displacement in hydrocarbon-bearing layers

Pardo D.; Torres-Verdín C.; Zhang Z. (Geophysics, 2008-12-31)

We study the theoretical response of electromagnetically energized steel casing in the presence of subsurface variations of electrical resistivity. Casing is energized with a finite-size solenoid antenna located along the ...

Energy-norm-based and goal-oriented automatic hp adaptivity for electromagnetics: Application to waveguide Discontinuities

Garcia-Castillo L.E.; Pardo D.; Demkowicz L.F. (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., ...

Rigorous numerics in floquet theory: Computing stable and unstable bundles of periodic orbits

Castelli R.; Lessard J.-P. (SIAM Journal on Applied Dynamical Systems, 2013-12-31)

In this paper, a rigorous method to compute Floquet normal forms of fundamental matrix solutions of nonautonomous linear differential equations with periodic coefficients is introduced. The Floquet normal form of a fundamental ...

Discrete nonnegativity for nonlinear cooperative parabolic PDE systems with non-monotone coupling

Faragó I.; Karátson J.; Korotov S. (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 ...

Singular dynamics under a weak potential on a sphere

Castelli R.; Paparella F.; Portaluri A. (Nonlinear Differential Equations and Applications, 2013-12-31)

We give a detailed analytical description of the global dynamics of a point mass moving on a sphere under the action of a logarithmic potential. We perform a McGehee-type blow-up in order to cope with the singularity of ...

An IMEX scheme combined with Richardson extrapolation methods for some reaction-diffusion equations

Faragó I.; Izsák F.; Szabó T. (Idojaras, 2013-12-31)

An implicit-explicit (IMEX) method is combined with some so-called Richardson extrapolation (RiEx) methods for the numerical solution of reaction-diffusion equations with pure Neumann boundary conditions. The results are ...

Editors' preface for the topical issue "Numerical Methods for Large-Scale Scientific Computing, II"

Karátson J.; Korotov S.; Margenov S. (Central European Journal of Mathematics, 2013-12-31)

[No abstract available]

Editors' preface for the topical issue "Numerical Methods for Large-Scale Scientific Computing, I"

Karátson J.; Korotov S.; Margenov S. (Central European Journal of Mathematics, 2013-12-31)

[No abstract available]

Simulation of DC dual-laterolog measurements in complex formations: A Fourier-series approach with nonorthogonal coordinates and self-adapting finite elements

Nam M.J.; Pardo D.; Torres-Verdín C. (Geophysics, 2009-12-31)

Dual laterolog (DLL) makes use of a galvanic conduction principle to focus electrical currents into rock formations, thereby minimizing shoulder and borehole effects in the measurement of formation resistivity. The tool ...