Matheon-Siegel AFEM HU-Siegel
Numerische Analysis
Prof. C. Carstensen

Research Seminar SoSe 2017

Organisation

Prof. Carsten Carstensen

Contact: Friederike Hellwig (hellwigf@math.hu-berlin.de)

Location

Humboldt-Universität zu Berlin, Institut für Mathematik

Rudower Chaussee 25, 12489 Berlin

Room 2.417

Schedule

April 19, 2017 09:15 Joscha Gedicke, Universität Wien
»An adaptive finite element method for two-dimensional Maxwell's equations« (Abstract)
April 26, 2017 09:15 Johannes Storn, HU Berlin
»Asymptotic Exactness of the Least-Squares Finite Element Residual«
May 3, 2017 09:15 Georgi Mitsov, HU Berlin
»Discrete Gronwall-type estimates for a family of discontinuous Petrov-Galerkin methods for the time-dependent Maxwell equations, Part I«
May 9, 2017 14:00 Georgi Mitsov, HU Berlin
»Discrete Gronwall-type estimates for a family of discontinuous Petrov-Galerkin methods for the time-dependent Maxwell equations, Part II«
May 10, 2017 09:15 Nando Farchmin, HU Berlin
»Analysis of a dPG FEM for Optimal Material Design«
May 16, 2017 14:00 Georgi Mitsov, HU Berlin
»Discrete Gronwall-type estimates for a family of discontinuous Petrov-Galerkin methods for the time-dependent Maxwell equations, Part III«
May 17, 2017 09:15 Lukas Gehring, HU Berlin
»Die Konstante in dem Satz von Binev-Dahmen-DeVore (über die Gesamtzahl von Dreiecken bei AFEM)«
May 31, 2017 09:15 Philipp Bringmann, HU Berlin
»Rate optimal adaptive least-squares finite element scheme for the Stokes equations«
June 14, 2017 09:15 Stephan Schwöbel, HU Berlin
»Übertragung einer dPG-Methode in eine Least Squares Methode«
June 21, 2017 09:15 Lukas Gehring, HU Berlin
»Die Konstante in dem Satz von Binev-Dahmen-DeVore, Teil II«
June 28, 2017 09:15 Andreas Veeser, University of Milan
»Quasi-optimality in parabolic spatial semidiscretizations« (Abstract)
July 11, 2017 13:30 Friederike Hellwig, HU Berlin
»Nonlinear Discontinuous Petrov-Galerkin Methods«
July 18, 2017 13:30 Philipp Bringmann, HU Berlin
»Quasi-interpolation operators for Nédélec functions - A short review«
July 18, 2017 14:00 Johannes Storn, HU Berlin
»Asymptotic Exactness of the Least-Squares Finite Element Residual, Part II«

Abstracts

Joscha Gedicke: An adaptive finite element method for two-dimensional Maxwell's equations

We extend the Hodge decomposition approach for the cavity problem of two-dimensional time harmonic Maxwell's equations to include the impedance boundary condition, with anisotropic electric permittivity and sign changing magnetic permeability. We derive error estimates for a P1 finite element method based on the Hodge decomposition approach and develop a residual type a posteriori error estimator. We show that adaptive mesh refinement leads empirically to smaller errors than uniform mesh refinement for numerical experiments that involve metamaterials and electromagnetic cloaking. The well-posedness of the cavity problem when both electric permittivity and magnetic permeability can change sign is also discussed and verified for the numerical approximation of a flat lens experiment.

Andreas Veeser: Quasi-optimality in parabolic spatial semidiscretizations

We analyze the interplay of the time derivative and the spatial discretization of parabolic initial-boundary value problems. Addressing time-independent and time-dependent spatial discretizations, our focus is on quasi-optimality and best error localization. Best error localization means that the best error over the whole domain is equivalent to an l2-norm of best errors over small subdomains, which ideally are mesh elements. The key tool for quasi-optimality is the inf-sup theory, with a formula for the quasi-optimality constant which is of independent interest.