**Dr. Ralf
Hiptmair: Presentations**

Current as of January, 2012.

*Multigrid Method for Maxwell's equations*, Conference on ``Adaptive methods for partial differential equations'', Mathematisches Forschungsinstitut Oberwolfach, February 16-22, 1997*Domain Decomposition for Eddy Current Problems*, Conference on ``Domain Decomposition and Multifield Theories'', Mathematisches Forschungsinstitut Oberwolfach, April 26 - May 2nd, 1998.*Multigrid for Eddy Current Computation*, Contribution at ``Advanced workshop on multigrid methods'', PennState University, College Park, PA, June 19-24, 2000.*Diskrete Hodge-Operatoren*, Main talk in session ``Numerical analysis, scientific computing, industrial mathematics'' at DMV Annual Meeting 2000, Dresden, September 18-22, 2000.*FEM-BEM Coupling for Eddy Current Problems*, Plenary lecture at GAMM-Workshop ``Computational Electromagnetism'', Kiel, January 26- 28, 2001*Mixed Finite Elements on Sparse Grids*, Conference on ``Mixed finite elements and applications'', Mathematisches Forschungsinstitut Oberwolfach, February 4-10, 2001*Multigrid solution of mixed eigenproblems*, Main talk in session on ``Domain decomposition methods'' at GAMM annual meeting 2001, Zürich, February 12-15, 2001.*Multigrid in H(*, Conference on ``Fast solvers for partial differential equations'', Mathematisches Forschungsinstitut Oberwolfach, May 28th - June 1st, 2001.**curl**): Latest News*Multigrid for Edge Elements*, 2nd Danish Symposium on Applied Analysis, Aug 23-25, 2001, University of Copenhagen, Copenhagen, Denmark.*Coupling of Circuits and Fields*, Conference on Modelling, Simulation and Optimization of integrated circuits, Oberwolfach, Nov 25 - Dec 1, 2001.*Discrete Differential Forms*, NSF-CBMS regional conference in the mathematical sciences ``Numerical methods in forward and inverse electromagnetic scattering'', Golden, CO, June 3-7, 2002.*Discretization of Maxwell's Equations*, Workshop on numerical relativity, IMA Minneapolis, MN, June 24-29, 2002.*Multigrid for Edge Elements: A Survey*European Multigrid Conference, Oct 7-10, 2002, Hohenwart, Germany*A Coupled Boundary Element Scheme for Eddy Current Computation*2. Kolloquium Elektromagnetische Umformung, Universität Dortmund, Germnay, May 27, 2003.*Domain Decomposition Preconditioners for Edge Elements: A survey*15th International Conference on Domain Decmposition Methods, July 21-25,2003, Berlin, Germany*Boundary Element Methods for Eddy Current Computation*Invited plenary lecture at ENUMATH'03 conference Aug 18-22, 2003, Prague*Non-reflecting boundary conditions for Maxwell's equations*Talk at the 20th GAMM Seminar on Numerical Methods for Non-local Operators, Leipzig, Jan 22-24, 2004*Higher order Whitney Forms*, Invited presentation at the IMA Special Topics Workshop on ``Compatible Spatial Discretizations for Partial Differential Equations'', Minneapolis, May 11-15, 2004.*Multigrid in H(curl)*, Invited presentation at ICCES Kolloquium, Hannover, July 3, 2004*Stable coupling for scattering*, Presentation at the Oberwolfach conference about numerical methods for non-local operators, Mathematisches Forschungsinstitut Oberwolfach, Jul 5-9, 2004, Oberwolfach, Germany.Invited survey lectures on

*Edge elements and coercivity*and*Multigrid for Edge Elements*, 29th Woudschoten Conference, Zeist, The Netherlands, October 6-8, 2004.Presentation on

*Conservative Discretization of Einstein-Dirac Equations with Spherical Symmetry*, BIRS Workshop on Numerical Relativity, Banff, Canada, April 16-21, 2005.*Operator preconditioning*, Presentation at the Oberwolfach Conference on Fast Solver for Partial Differential Equations, May 22-28, 2005.*Current and Voltage Excitations for the Eddy Current Model*, International Conference on Hot Topics in Applied and Industrial Mathematics Guiyang, Guizhou, China, July 13-16, 2005.*Multigrid for Maxwell Eigenproblems*, European Multigrid Conference, Scheveningen, the Netherlands, 27-30 September 2005.*Gauge conditions for Maxwell's equations in anisotropic media*, 3rd Schlumberger study group on Applied Mathematics, Sugar Land, Texas, Jan 11-13,2006.*Topologie im industriellen Einsatz*, Abschlusskolloquium des Sonderforschungsbereichs 382, Stuttgart, 17.-20. September 2006*Edge elements and coercivity*, 19th Chemnitz FEM Symposium, Chemnitz, Germany, Sep 25-27, 2006.*Coupling techniques for wave propagation*, workshop "The Future of Computational Acoustics", Isaac Newton Institute/Noise Futures Network Event, Arup Acoustics, London, Feb 22-23, 2007.*Excitation*, 4th workshop on Advanced Computational Electromagnetics (ACE'07), Aachen, Germany, Jun 28-Jun 30, 2007.*Plane wave discontinuous Galerkin methods*, workshop on "Effective computational methods for highly oscillatory problems: The interplay between mathematical theory and applications" at Isaac Newton Institute, Cambridge, UK, July 1-5, 2007.*Galerkin boundary element methods*, 3rd Workshop on Numerical Methods for Optical Nano Structures, ETH Zurich, July 9-19, 2007.*Plane Wave Discontinuous Galerkin Methods*, Workshop on High-order methods for computational wave propagation and scattering, American Institute of Mathematics (AIM), Palo Alto, CA, Sep 10-14,2007.*Discrete Electromagnetism*, Invited plenary lecture at the GAMM Annual Meeting 2008, Bremen, March 31 - April 4, 2008.*Multi-dielectric Electromagnetic Scattering*, talk at Oberwolfach Conference on Analysis of Boundary Element Methods, April 13-19, 2008.*Robust Maxwell Formulations*, talk at Oberwolfach Conference on Fast Solvers for PDE, May 19-23, 2008.*BEM for Electromagnetics: Topological Issues*, invited lecture at the workshop 'BEM on the Saar 2008', May 26-29, 2008, Saarbruecken, Germany*Continuous and discrete Helmholtz decompositions*, invited semiplenary lecture at Foundations of Computational Mathematics Conference, Workshop B4 on Foundations of Numerical PDEs, Hong Kong, June 6-26, 2008.*Plane Wave Discontinuous Galerkin Methods*, invited lecture at 5th workshop of Advanced Computational Electromagnetism (ACE), January 12-15, 2009, Rome*Regularized Combined Field Integral Equations*, invited plenary lecture at the 9th International Conference on Mathematical and Numerical Aspects of Waves Propagation, 15th-19th June 2009, Pau, France*Operator preconditioning*, invited lecture at the Conference on Compatible and Innovative Discretizations for Partial Differential Equations. Algorithms, analysis, and implementation on the occasion of Ragnar Winther's 60th birthday, Oslo, Norway, June 17-19, 2009.*Discrete Regular Decompositions*, invited plenary lecture at 23rd Biennial Conference on Numerical Analysis, June 23rd - 26th 2009, University of Strathclyde, Glasgow, Scotland, UK.*Discrete Compactness for Spectral Edge Elements*, talk at Oberwolfach conference on Linear and Nonlinear Eigenproblems for PDEs, August 9-15, 2009.*Theory of "good" and "bad" meshes*, Rüdlinger Tagung 2009 der ZHAW, Rüdlingen, Aug 31 - Sep 1, 2009.*Discrete Lie Derivatives: Semi-Lagrangian Approach*, Converence on Mathematical Physics and PDEs, Levico Terme, Italy, Sep 6-11, 2009.*Operator preconditioning*, GAMM Workshop on Applied and Numerical Linear Algebra, ETH Zürich, Sep 10-11, 2009.*Plane wave discontinuous Galerkin methods*, Workshop on non-standard numerical methods for PDEs, Pavia, June 29-July 2, 2010.*Sparse Adaptive Tensor Product Methods for Radiative Transfer*, ESF-INI Conference on the Theory of Highly Oscillatory Problems: From Theory to Applications. Sep 13-17 2010, Isaac Newton Institute, Cambridge.*Sparse Adaptive Tensor Product Methods for Radiative Transfer*, Workshop on Sparse Grids and Applications, Hausdorff Research Institute for Mathematics, Bonn, May 16-20, 2011.*Multilevel Preconditioning for Boundary Element Methods*, Oberwolfach workshop on Fast Solvers for Partial Differential Equations, May 26-30, 2011, Oberwolfach, Germany.*Frequency domain boundary element methods*, 7th Workshop on Numerical Methods for Optical Nano Structures, ETH Zürich, July 4-6, 2011-
*(Multilevel) preconditioning for Boundary Element Methods*First China Workshop on Algebraic Multigrid Methods, Kunming, Yunnan, China, August 1-10, 2011 *Operator preconditioning*, Workshop on Numerical Electromagnetics and Industrial Applications (NELIA 2011), October 25 - 28, 2011, Faculty of Mathematics, Universidade de Santiago de Compostela, Spain*Convergence of Truncated T-matrix approximation*, Workshop on Wave Propagation and Scattering, Inverse Problems and Applications, RICAM, Linz, November 21-25, 2011.*Boundary Element Methods for Eddy Current Computation*, 2nd CI^{2}MA Focus Seminar "Computational Electromagnetics", Universidad de Concepcion, Chile, Jan 5, 2012.*Sparse Adaptive Finite Elements for Radiative Transfer*, Segundo Encuentro de la Matematica y sus Aplicaciones, Valparaiso, Chile, Jan 19-20, 2012.*Convergence of hp-BEM for the Electric Field Integral Equation*, Workshop on High-Order Numerical Approximation for Partial Differential Equations, Haussdorff Institute for Mathematics, Bonn, Germany, Feb 6-10, 2012.*Novel Boundary Element Methods for Scattering at Composite Objects*Workshop on Wave Propagation in Complex Media and Applications, Heraklion, Crete, May 7-12, 2012.*Novel Boundary Element Methods for Scattering at Composite Objects*Workshop on Boundary value problems for linear elliptic and integrable PDEs: Theory and computation, ICMS Edinburgh, May 28 - June 1, 2012*Multi-Trace Boundary Element Methods*, 21st International Conference on Domain Decomposition Methods, 25-29 June 2012, INRIA Rennes, France, video.*Sparse Tensor Edge Elements*, Oberwolfach Mini-Workshop on Efficient and Robust Approximation of the Helmholtz Equation, MFO Oberwolfach, Nov 26-30, 2012.*Continuous and Discrete Helmholtz-type decompositions*, Swiss-Japanese Seminar, Universität Zürich, Dec 17-19, 2012.*Cut-off Estimates For Non-Local Trace Norms*, FIRST Workshop on Non-Local Prblems, Universität Zürich, Dec 12-14, 2012.*Sparse Tensor Edge Elements*, Plenary lecture at FOURTH CHILEAN WORKSHOP ON NUMERICAL ANALYSIS OF PARTIAL DIFFERENTIAL EQUATIONS (WONAPDE), Universidad de Concepcion, Concepcion, Chile, January 14 - 18, 2013.*Discretization of Advection-Diffusion of Magnetic Fields*, IFIP TC7.2 Workshop, Electromagnetics – Modelling, Simulation, Control and Industrial Applications, WIAS Berlin, May 13 - 17, 2013.*Boundary Integral Equations on Complex Screens*, Journees Singulieres Augment\'ees 2013 , Conf\'erence en l'honneur de Martin Costabel, Rennes, France, Aug 26-30, 2013.*Self-adjoint Curl Operators*, Oberwolfach Workshop on the Numerical Solution of PDE Eigenvalue Problems, MFO Oberwolfach, Nov 17-23, 2013.*Discretizing the Advection of Differential Forms*ICERM Topical Workshop on Robust Discretization and Fast Solvers for Computable Multi-Physics Models ICERM, Providence, RI, May 12-16, 2014.*Operator preconditioning for boundary elements on curves*ICMS Workshop on Boundary Integral Equations: Analysis and Computation Edinburgh, May 27-29, 2014.*Continuous and Discrete Helmholtz-type Decompositions*, CIRM International Conference on Fluid dynamics and electromagnetism: theory and numerical approximation Levico Terme, Italy, June 3-6, 2014.*Maxwell's Equations: Continuous and Discrete*, 7 hour**short course**as part of CIME program on Computational Electroamgnetics, June 9-14, 2014, Cetraro, Italy.*Plane Wave Discontinuous Galerkin Methods*, EPSRC-LMS Durham Symposium "Building bridges: connections and challenges in modern approaches to numerical partial differential equations", Durham, UK, July 8-16, 2014*Multiple Point Evaluation on Combined Tensor Product Supports*, 3rd Workshop on Sparse Grids and Applications, University of Stuttgart Germany Sep 1-5, 2014.*Discretization of Advection-Diffusion of Magnetic Fields*, IMA Special Workshop Structure-Preserving Discretizations of Partial Differential Equations Minneapolis, October 22-24, 2014.*Plane Wave Discontinuous Galerkin Methods*, Plenary lecture at the International Conference on Numerical Partial Differential Equations and Their Applications, Wuhan, China, May 25-29, 2015*Discretizing the Advection of Differential Forms*, Workshop on Advances in DG and Related Issues, International Academic Forum Heidelberg, Dec 14-16, 2015.*Plane Wave Discontinuous Galerkin Methods*, Computational Seismology Workshop, Tsinghua Sanya International Mathematics Forum (TSIMF), Jan 4-8, 2016.*Discretizing the Advection of Differential Forms*, BIRS Workshop on Computational and Numerical Analysis of Transient Problems in Acoustics, Elasticity, and Electromagnetism, Banff, Canada, Jan 18-22, 2016.*Second-kind Single-Trace Boundary Integral Equations*, Workshop on New Trends in Integral Equations, Ecole Polytechnique, Palaiseau, France, Feb 4-5, 2016.-
*Auxiliary Space Precondtioning for Edge Elements*, EMF 2016 (10th International Symposium on Electric and Magnetic Fields) , Lyon, France, April 12-14, 2016. -
*Operator Preconditioning on Screens*, 8th Singular Day, Nacny, France, June 27-30, 2016. -
*Multi-trace boundary element methods*, 14th International Conference on Integral Methods in Science and Engineering, ISEM, Padova, Italy, July 25-29, 2016. -
*Second-Kind Boundary Integral Equations for Electromagnetic Scattering at Composite Objects*, RICAM Workshop on Analysis and Numerics of Acoustic and Electromagnetic Problems, Linz, Austria, Oct 17-20, 2016. *Discrete Compactnesss for $p$-Version Finite Elements*Numerics and Mathematical Analysis for Singularities and Eigenvalue Problems, IRMAR, Rennes, Feb 8-10, 2017.-
*Boundary Integral Equations on Complex Screens*, Workshop on Wave Propagation in Complex Domains, University College London, March 30, 2017 -
*Exterior Shape Calculus*, Oberwolfach Workshop on Computational Inverse Problems, MFO, May 15-19, 2017, -
*First-Kind Boundary Element Methods for Hodge-Laplacians*, Workshop "Waves Diffracted by Patrick Joly”, Gif-sur-Yvette, France, August 28-30, 2017 *Operator Preconditioning: Theory and Applications*, 7th International Conference on Advanced Computational Methds in Egineering (ACOMEN) Gent, Belgium, Sep 18-22, 2017.-
*First-Kind Boundary Element Methods for Hodge-Laplacians*, Workshop on Numerical PDEs, Pontificia Universidad Santiago de Chile, January 25, 2018 -
*Regular Recompositions: Discrete, Boundary-Aware, and p-Stable*, Plenary talk at the International Conference on Spectral and High-Order Methods (ICOSAHOM 2018), London, July 9-13, 2018. (co-author: Clemens Pechstein) -
*Coupling Finite Elements and Multiple Multipoles*, Talk in MS31*Numerical Solution of High Frequency Scattering Problems*at the International Conference on Spectral and High-Order Methods (ICOSAHOM 2018), London, July 9-13, 2018. (co-author: Daniele Casati) -
*Approximating Shape Gradients*Talk at Workshop on the*Interplay of geometric processing, modelling, and adaptivity in Galerkin methods*as part of the*ESI Programme on Numerical Analysis of Complex PDE Models in the Sciences*, Erwin Schrödinger Institut, Wien, July 16-20, 2018. -
*Multi-Trace Boundary Element Methods*, Invited plenary lecture at the MAFELAP 2019 Conference, Brunel University, London ,UK, June 18-21, 2019. -
*Exterior Shape Calculus*, Seminar talk, Program on on Geometry, Compatibility and Structure Preservation in Computational Differential Equations, Isaac Newton Institute for Mathematical Sciences Cambridge, UK, July 22, 2019. Link -
*Electrostatic Force Computation with BEM*, Oberwolfach Workshop on Boundary Element Methods, MFO, Germany, Feb 20, 2020. -
*Discretizing the Advection of Differential Forms*Workshop on Structure, Regularity, and Robustness in the Approximation of Partial Differential Equations, Universita degli Studi di Milano, Milan, Italy, Feb 10, 2020. -
*The Topolgy of Field-Circuit Coupling*CIRM Workshop on Energy-Based Modeling, Simulation, and Control of Complex Constrained Multiphysical Systems, CIRM, Luminy, France, April 18-22, 2022. -
*Frequency-Explicit Shape Uncertainty Quantification for Acoustic Scattering: A Case Study*Workshop on UQ in Kinetic and Transport Equations and in High-Frequency Wave Propagation, ESI Vienna, June 13 - June 17, 2022. -
*Regular Decompositions: Discrete, Boundary-Aware, and p-Stable*GATIPOR Workshop 2022 Interplay of discretization and algebraic solvers: A posteriori error estimates and adaptivity Paris, June 8-10, 2022 -
*Traces for Hilbert Complexes*Oberwolfach Workshop on Hilbert Complexes: Analysis, Applications, and Discretizations MFO, Oberwolfach, June 19-25, 2022. -
*The Topolgy of Field-Circuit Coupling*URSI Workshop Felder und Wellen, Raitenhaslach, 29.6.-1.7.2022. -
*Inherited Multigrid*

*Object oriented concepts for a finite element code*(*Objektorientierte Konzepte für einen adaptiven FE-Code*), Workshop on Pre- and Postprocessing, Universität Chemnitz-Zwickau, June 1993.*Mixed finite elements in semiconductor device simulation*(*Gemischte Finite Elemente in der Halbleitersimulation*), SCTP-Workshop (Scientific Computing in der Theoretischen Physik), Berlin 16.03-18.03.1994*Multilevel Methods for Convection-dominated Problems*, Talk at 2nd Gauss Symposium, session on Numerical Analysis, Munich, Germany, July 1993.*A Stabilized Mixed Discretization of Continuity Equations Arising in Semiconductor Simulation*, Talk in minisymposium on ``Seminconductor Device Simulation'', ECMI Annual Meeting, Kaiserslautern, Germany, 1994.*Multilevel Augmented Lagrangian Methods for 2nd Order Mixed Problems*, Workshop on Recent Advances in Numerical Methods for Partial Differential Equations, Politecnico Torino, Torino, Italy, August 1995.*Concepts for an Object Oriented Finite Element Code*, DMV-GAMM-Workshop ``Software Engineering in Scientific Computing'', Hamburg, Germany, June 6-8 1995.*Nonconforming Mixed Finite Elements*, Talk in session on Numerical Analysis, DMV Annual Meeting 1995, Ulm, Germany, Sep 17-23 1995.*Multigrid Methods for Mixed Finite Elements in 3D*(*Mehrgitterverfahren für gemischte Finite Elemente in 3D*), BMBF-Workshop on multigrid methods, Augsburg, Germany, June 1996.*Operator Representation and Handling in an Object Oriented Adaptive Finite Element Code*, AMFEM-Workshop (Adaptive Methods for Finite Elements), WIAS-Berlin, Berlin, Germany, August 1996.*Multilevel Methods for Mixed FEM*, European Multigrid Conference, Stuttgart, Germany, Oct 1-5 1996.*Preliminary results on the 3D Simulation of an Electrorheological Fluid*, Talk in session on Numerical Analysis, GAMM Annual Meeting 1997, Regensburg, Germany, March 24-27 1997.*Multigrid Method for H(div) in Three Dimensions*, Eighth Copper Mountain Conference on Multigrid Methods, Copper Mountain, CO, April 1997.*Multigrid Method for Maxwell's Equations*, Finite Element Circus, New York, NY, April 1997*Multigrid Method for Maxwell's Equations*, Workshop ``Parallel Solution of PDE'', IMA, Minneapolis, June 1997.*Adaptive multilevel methods for Maxwell's equations*(*Adaptive Multilevelverfahren für die Maxwellgleichungen*), 1st SCEE-Conference (Scientific Computing in Electrical Engineering) of the DMV Special Interest Group ``Scientific Computing'', Darmstadt, Germany, July 1997.*Multigrid Method for Maxwell's Equations*, ENUMATH'97 conference, Heidelberg, Germany, Sept 29 - Oct 3 1997.*Multigrid for quasistatic field problems*(*Mehrgitter für quasistationäre Feldprobleme*), Workshop ``Finite Elements in Structural Mechanics'', Bochum, Germany, June 19-20 1998.*Topology optimization with perimeter constraint*(*Topologieoptimierung mit Umfangsbeschränkung*), Workshop ``Shape- and Topology Optimization'', Güunzburg, Germany, July 1998.*Multigrid for FIT*, 2nd SCEE-Conference (Scientific Computing in Electrical Engineering), Berlin, Sept 30 - Oct 3 1998.*Multigrid in H(div) and H(*, GAMM - Workshop on Multigrid Methods, Bonn, Germany, Oct 5-8 1998.**curl**)*Hierarchical Error Estimator for Whitney Elements*, Workshop on Adaptive Finite Element Methods and Optimzation (AMFEM), Heidelberg, Germany, Nov 19-21 1998.*A Posteriori Error Estimators for Edge Elements*, ENUMATH'99 conference, University of Jyväskylä, Finland, July 26-30 1999.*Stable Multilevel Gauging*, Talk in minisymposium on ``Computational electromagnetism'', ENUMATH'99 conference, University of Jyväskylä, Finland, July 26-30 1999.*Discrete Hodge operators*, Workshop ``Discretization Methods in Electromagnetic Field Computation'', Rostock, Germany, August 1999.*A posteriori error estimation for edge elements*, GAMM-Workshop on Adaptive Methods and Error Estimators, Kiel, Germany, Jan 21st - 23rd, 2000.*Symmetric Coupling for Eddy Current Computation*, GAMM Annual Meeting 2000, Göttingen, Germany, April 2-7 2000.*FEM-BEM Coupling for Eddy Current Problems*, Workshop ``FEM-BEM Kopplung: Schnelle Algorithmen und ihre Implementierung'', Kleinwalsertal, Austria, June 1-4 2000.*Higher Order Whitney Forms*, Talk in session on ``Geometrical and Topological Issues in Three Dimensional Finite Element Analysis'', PIERS-Conference (Progress in Electromagnetic Research Symposium), Cambridge, MA, July 5-14 2000.*Multigrid Computation of Maxwell Eigenvalues*, 3rd SCEE-Conference (Scientific computing in electrical engineering), Rostock, Germany, August 20-23 2000.*The Maxwell-Helmholtz equations*(*Die Maxwell-Helmholtz-Gleichungen*), BMBF workshop ``Modern Numerical Methods for the Helmholtz Equation'', Stuttgart, Germany, March 2-3 2001.*FEM-BEM coupling in electromagnetic scattering*, Workshop on Modern Aspects of Boundary Element Methods, Stuttgart, Germany, Oct 15-16 2001.*Ecken, Kanten und Feldapproximation*, Talk at 3rd Edyson-Anwendertreffens, Bosch Corp., Stuttgart, Jan 31, 2002.*Transmission Problems in Eddy Current Computation*, Talk in minisyposium on domain decomposition methods, European Symposium on Numerical Methods in Electromagnetics, Toulouse, France, March 6-8, 2002.*Construction and Classification of Surface Cycles*, Talk in session on integral equations, European Symposium on Numerical Methods in Electromagnetics, Toulouse, France, March 6-8, 2002.*Discrete Differential Forms*, Talk in minisyposium on Geometric Integration of PDEs at SciCADE 2003 conference, Jun 30 - Jul 4, 2003, Trondheim, Norway*Coercive Combined Field Integral Equations*, Meeting on Waves, University of Reading, Reading UK, Sep 11, 2003*Symmetric Coupling of FEM and BEM for Eddy Current Computations*, Fourth UK conference on boundary integral methods, University of Salford, Sep 15-16, 2003.*Coercive Combined Field Integral Equations*Workshop on Fast Boundary Element Methods in Industrial Applications, Söllerhaus (Kleinwalsertal), Austria, Oct 15-18, 2003*Surface edge elements*, Keynote lecture in minisyposium on Fast Boundary Element Methods at Sixth World Congress on Computational Mechanics (WCCM VI), Beijing, PR China, Sep 5-10, 2004*The Curse of Dispersion*Workshop on Numerical Methods for Optical Nanostructures, ETH Zürich January 20, 2005.*Computing representations of curl-free surface fields*, special session on equations with inherent constraints at Joint Meeting of AMS, DMV and ÖMG, Main, June 16-19, 2005.*Discrete regular decompositions*, 4th European Finite Element Fair, June 2-3 2006, ETH Zuerich.*Nodal auxiliary space preconditioning for edge elements,*MAFELAP'06 conference, Brunel University, London, June 13-16, 2006.*Auxiliary space preconditioning in H(curl),*talk in minisympoisum on "subspace correction methods" at 17th International Conference on Domain Decomposition Methods, Strobl, Austria, July 3-7, 2006.*Resonance free interface coupled BEM for scattering,*talk in minisympoisum on "Domain Decomposition based on Boundary Elements" at 17th International Conference on Domain Decomposition Methods, Strobl, Austria, July 3-7, 2006.*Regularized Combined Field Integral Equations,*contributed talk at IABEM 2006 Conference, Graz, Austria, July 10-12, 2006.*Combined Field Integral Equations,*talk at GAMM-Seminar, Leipzig, Jan 25-27, 2007.*Auxiliary space preconditioners for electromagnetics*, Minisymposium on Adaptive and multilevel methods in electromagnetics, 6th International Congress on Industrial and Applied Mathematics, ICIAM, Zürich, July 16-20, 2007.*Regular decompositions and multigrid analysis*, Minisymposium on Adaptive and multilevel methods: design, analysis, and application. 6th International Congress on Industrial and Applied Mathematics, ICIAM, Zürich, July 16-20, 2007.*Auxiliary space preconditioning in H(curl),*talk in session on Multigrid and Domain Decomposition Methods at 9th International Workshop on Finite Elements for Microwave Engineering, May 8-9, Bonn*Excitation*, talk in session Waveguide \& Lumped Elements at 9th International Workshop on Finite Elements for Microwave Engineering, May 8-9, Bonn*Force Computation: Mathematical Recipes*, talk in session Advanced FEM at 9th International Workshop on Finite Elements for Microwave Engineering, May 8-9, Bonn*Plane wave discontinuous Galerkin methods*, presentation in minisymposium on Mathematical Analysis of Generalized Finite Element Methods, ECCOMAS 2008 conference, Venice, Italy, June 30-July 4, 2008.*Plane Wave Discontinuot Galerkin Methods: Convergence Theory*Presentation in minisymposium on*FEM with non-polynomial basis functions*at MAFELAP 2009, Brunel University, London, UK, June 9-12, 2009.*Discrete Lie Derivatives*, Talk in Minisymposium on*Structure preserving discretization of PDEs*, Conference BIT 50 - Trends in Numerical Computing, Lund, Sweden, June 17-20, 2010.*Auxiliary space methods for edge elements*, Talk in Minisymposium on Optimal Solvers from Multi-grid and Two-grid to One-grid and No-grid, 20th International Conference on Domain Decomposition Methods, La Jolla, CA, Feb 7-11, 2011.*Multiple traces boundary integral formulations for Helmholtz transmission problems*, Talk in Minisymposium on Domain Decomposition Methods in Computational Electromagnetics, 20th International Conference on Domain Decomposition Methods, La Jolla, CA, Feb 7-11, 2011.*Multilevel Preconditioning for Edge Boundary Elements*, 9th Söllerhaus Workshop on Fast Boundary Element Methods in Industrial Applications, Sep 29 - Oct 2, 2011, Hirschegg, Kleinwalsertal, Austria*Boundary Element Methods for Scattering at Composite Objects*, ACE2012 - 7th Workshop on Advanced Computational Electromagnetics, Karlsruhe Institute of Technology, Karlsruhe, Germany, Feb 29 - Mar 2, 2012.*Multi-trace Boundary Integral Equations*, Symposium of the International Association for Boundary Element Methods (IABEM 2013), Pontificia Universidad Cat\'olica de Chile, Santiago de Chile, Jan 9-11, 2013.*BETL: Enhancements at ETH*, Presentation at CASOPT closing workshop, ABB Corporate Research Baden Dättwil, March 12, 2013.*Combined field integral equations for acoustic scattering by partially impenetrable composite objects*, 11th Workshop on FAST BOUNDARY ELEMENT METHODS IN INDUSTRIAL APPLICATIONS Soellerhaus, Kleinwalsertal, Austria, 26.-29.9.2013.*Discrete Shape Gradients*, 12th European Finite Element Fair, Vienna, May 29-30, 2014.*Discrete Shape Gradients*, IMA Special Workshop Finite Element Circus, Minneapolis, October 24-25, 2014.*Cut-free Boundary Elements for Magnetic Potentials*, 13. Workshop Fast Boundary Element Methods in Industrial Applications Söllerhaus, Austria, OCt 23-26, 2015.*Dispersion Analysis of Plane Wave Discontinuous Galerkin Methods*, Minisymposium on Recent Advances in Enriched Finite and Boundary Element Methods, MAFELAP conference, Brunel University, London, June 14-17, 2016.*Second-Kind Single-Trace Boundary Integral Equations*, Minisymposium on Recent Advances in Boundary Element Methods, MAFELAP conference, Brunel University, London, June 14-17, 2016.-
*Second-Kind Single-Trace Boundary Integral Equations*, 14th S\"ollerhaus Workhop on Fast Boundary Element Methods and Industrial Applications, Kleinwalsertal, Oct 9-12, 2016. -
*Multilevel Decompositions of Boundary Element Spaces and Applications*, talk in Minisymposium on Multilevel Algorithms and Theories, International Conference on Multigrid and Multiscale Methods, IMG, Bruchsal, Dec 5-9, 2016. -
*Exterior Shape Calculus*, Main talk in Section on Opitmization of Partial Differential Equations, GAMM Annual Meeting 2018, TU München, March 23, 2018. -
*Shape Gradients in Finite Element Exterior Calculus*Talk in the minisymposium on Shape Optimization: Theory and Practice at the 2019 MAFELAP Conference, Brunel University, Uxbridge, UK, June 18-21, 2019. -
*MFS-CQ for Acoustic Scattering*Talk in the Minisymposium in Memory of Francisco-Javier Sayas at the Congress on Differential Equations and Applications (CEDYA) Gijón, Spain, June 14-18, 2021. -
*Galerkin Boundary Element Methods for the Hodge-Laplacian*Talk in the Minisymposium on Advances in Computational Boundary Integral Equations for Electromagnetics at the Conference on Mathematics of Wave Phenomena Karlsruhe, Germany, Feb 14-18, 2022.

*Gemischte Finite Elemente in der Bauelementsimulation*, IWR Heidelberg, Heidelberg, Germany, August 26, 1993*Objektorierntierte Konzepte f"ur einen FE-Code*, Universität der Bundeswehr, Neubiberg, Germany, Nov 11, 1994*Multilevel-Zerlegung f"ur gemischte FEM*, Mathematisches Institut, Universität Würzburg, Würzburg, Germany, August 1996.*Multilevel-Zerlegung solenoidaler Vektorfelder mit Anwendungen*, ZIB-Berlin, Berlin, Germany, Nov 5, 1996.*Multigrid Method for Maxwell's Equations*, University of Delaware, April 5 1997.*Finite Elements for Differential Forms*, IMA, Minneapolis, June 1997.*Finite elements for Maxwell's equations*, University of Linköping, Sweden, Aug 27, 1997.*Numerische Simulation von Wirbelstromproblemen*, Universität Linz, Linz, Austria, Oct 8, 1997.*Numerische Lösung von Wirbelstromproblemen*, Universität Tübingen, Tübingen, Germany, Dec 2, 1997.*Mehrgitterverfahren zur Wirbelstromberechnung*, Universität Darmstadt, Darmstadt, Germany, Jan 12, 1998.*Multigrid Method for eddy current problems*, Bell Laboratories, Murray Hill NJ, March 1998.*A-posteriori Error Estimation for Edge Elements*, University of Delaware, March 1998.Series of lectures on

*Adaptive Multilevel Methods for Edge Elements*at Pennsylvania State University, March 1998 (Comprised four talks on*Maxwell's equations and discrete differential forms*,*Edge elements*,*Multilevel methods in H(*,**curl***A-posteriori Error Estimation for Edge Elements*).*Finite elements for Maxwell's equations*, Xiangtan University, Hunan, PR China, April 1998.Talks on

*Finite Elemente fü elektromagnetische Felder*and*Multilevelverfahren für Kantenelemente*, Institut für praktische Mathematik, Universität Kiel, Kiel, Germany, Oct 13-15, 1998.*Diskrete Differentialformen auf Simplices*, TU München, Munich, Nov 18, 1998.*Mehrgitterverfahren für Wirbelstromprobleme*, Institut für Numerische und Angewandte Mathematik, Universität Göttingen, Göttingen, Germany, Jan 19, 1999.*Multigrid in H(div) und H(*)**curl**

Fachbereich Mathematik, Universität-Gesamthochschule Essen, Essen, Germany, Jan 20, 1999.*Konstruktion diskreter Differentialformen*, Institut für Angewandte Mathematik (IAM), Universität Bonn, Bonn, Germany, Jan 21, 1999.*Diskretisierung der Maxwellgleichungen*, IWR Heidelberg, Heidelberg, Germany, Jul 7, 1999.*Kantenelemente*, WIAS Berlin, Berlin, Germany, Jul 15, 1999.*Multigrid for FIT*, Laboratory of Electromagnetics, Tampere University of Technology, Tampere, Finland, Aug 8, 1999.*Diskretisierung der Maxwellgleichungen*, Universität Linz, Linz, Austria, Sep 21, 1999.*Diskretisierung der Maxwellgleichungen*, Mathematisches Institut A, Universität Stuttgart, Stuttgart, Nov 4, 1999.*Multigrid for eddy current problems*, Xi'an Jiaotong Universty Science School, Xi'an, Shaaxi, PR China, Apr 26, 2000.*Multigrid for Maxwell's equations*, Department of Computational Mathematics, Beijing University (Beida), Beijing, PR China, May 4 2000.*FEM-BEM-Kopplung für Wirbelstromprobleme*, Research Center of DaimlerChrysler Corp., Ulm, Germany, Sep 14, 2000.*Multigrid for H(*, Los Alamos National Laboratory, Los Alamos, NM, Jul 18, 2000.**curl**)-Elliptic Boundary Value Problems*FEM-BEM coupling for eddy current problems*, Oberseminar Numerik, Universität Zürich, Zürich, Switzerland Nov 2, 2000.*Multigrid Computation of Maxwell Eigenvalues*, Universität Augsburg, Augsburg, Germany, Dec 7, 2000.*Multigrid Computation of Maxwell eigenvalues*, MPI Leipzig, Leipzig, Germany, Jan 30, 2001.*Discrete Hodge Operators*, Laboratoire de Mathematiques, Université de Metz, Metz, France, March 29, 2001.*Discrete Differential Forms on Simplices*, Seminar für Angewandte Mathematik, ETH Zürich, Zürich, Switzerland, April 18, 2001.*Edge Elements*, Department of Mathematics, University of Strasbourg, Strasbourg, France, June 5, 2001.*Direkte Randintegralformulierungen für die Maxwellgleichungen*, IAM, Universität Bonn, Bonn, Germany, June 26, 2001.*Generators of discrete homology classes: Algorithmic topology for car manufacturing*(*Generatoren diskreter Homologieklassen: Algorithmische Topologie für die Automobilindustrie*), Fakultät für Mathematik und Wirtschaftswissenschaften, Universität Ulm, Ulm, Germany, Jul 3, 2001.*Edge Elements*, R & D division of Bosch Corp., Stuttgart, Germany, Jul 5, 2001.*FEM-BEM Coupling in Electromagnetic Scattering*, Dipartimento di Matematica, Universitá degli Studi di Trento, Trento, Italy, Sep 18, 2001.*Discrete Differential Forms on Simplices*, Dipartimento di Matematica ``Felice Casorati'', Universitá degli Studi di Pavia, Pavia, Italien, Sep 19, 2001.*Automated local mode analysis*, Seminary lecture at University of Erlangen, Jan 17th, 2002..

*Kantenelemente*, Presentation at IZWR, Universität Jena, Jan 18th, 2002.*Simulation induktiven Härtens*, Vortrag im mathematischen Kolloqium an der Universität Kaiserslautern, Feb 19, 2002.*Higher Order Whitney Forms*, Lawrence Livermore National Lab, Livermore, CA, June 11, 2002.*Multigrid for Eddy Current Computation*, Lawrence Livermore National Lab, Livermore, CA, June 12, 2002.*Wenn Räume nicht ganz dicht sind - Funktionalanalysis auf dem Computer*Antrittsvorlesung Universität Tübingen, Dec 16, 2002, Tübingen*Multigrid Solution of Mixed Eigenproblems*University of Gent, Belgium, Jan 17, 2003*FEM-BEM Coupling for Eddy Current Problems*Chinese Academy of Sciences, Beijing, Feb 26, 2003.*FEM-BEM Coupling for Quasistatic Electromagnetism*Isaac Newton Institute for Mathematical Sciences, Cambridge, UK, Feb 18, 2003.*Coercive Combined Field Integral Equation for Direct Scattering*, ZIB-Berlin, Berlin, Germany, May 30, 2003.*Coercive Combined Field Integral Equations*, Numerical Analysis, Seminar, University of Bath, UK, Sep 17, 2003*Generators of Discrete Homology Classes: Algorithmic Topology in Car Manufacturing*Numerical Analysis Seminar, EPFL Lausanne, Nov 7, 2003*The impact of non-density*, Numerical Analysis Seminar, Uninversitaet Dresden, Jan 20, 2004, Presentation in Kolloquium, Department of Electrical Engineering, Universität der Bundeswehr, Feb 9, 2004.

, Ecole Centrale de Lyon, March 16, 2004.

*Theory of Boundary Elements for Electromagnetic Scattering*, MAPLY, Universite Lyon, March 16, 2004.*Kantenelemente*, Kolloqium des Fachbereichs Mathematik, Universität Düsseldorf, April 23, 2004.*Stable FEM-BEM Coupling for Acoustics*, POEMS Seminar, Project ONDES, INRIA, Rocquencourt, France, Oct 27, 2004.*Discrete Electromagnetics*, Deprtment of Mathematics, University of Alberta, Edmonton, Canada, April 22, 2005.*Surface Discrete Differential Forms and Duality*, Seminar of Mechanics and Computation Group, Department of Mechanical Engineering, Stanford University, April 26, 2005.*Discretization of Electromagnetic Fields*, IWRMM-Kolloquium, Universität Karlsruhe, May 19, 2005*Operator Preconditioning*, Seminar talk at Institute of Computational Mathematics, Chinese Academie of Sciences, Beijing, July 4, 2005., Kolloquium, Technische Universitaet Muenchen, Oct 27, 2005

*Spurious solutions explained,*presentation in Seminar on Computational Mathematics at university of Houston, Jan 9, 2006*Regularized combined field integral equations*, Wednesday Seminar, Newton Institute Cambridge, Feb 20, 2007*Local multigrid theory*, Numerical Analysis Seminar, Department of Mathematics, University of Strathclyde, Feb 27, 2007.*Continuous and Discrete Helmholtz-type Decompositions*, Mathematics Colloquium, Department of Mathematics, University of Strathclyde, Feb 28, 2007.*Analysis of plane wave discontinuous Galerkin methods*, Wednesday Seminar, Newton Institute Cambridge, Mar 7, 2007*Preconditioning Techniques for H(curl)-elliptic boundary value problems*, Fraunhofer Institut SCAI, St. Augustin, April 16, 2007*Plane wave discontinuous Galerkin Methods*, Seminar given at LSEC, Institute of Computational Mathematics, Chinese Academy of Sciences, Beijing, Oct 15, 2007.*Sparse tensor product Galerkin scheme for radiative transfer*, Seminar given at LSEC, Institute of Computational Mathematics, Chinese Academy of Sciences, Beijing, Oct 17, 2007.*Continuous and Discrete Helmholtz-type Decompositions*, Joint seminar of Department of Mathematics at CUHK and IMS, Nov 15, 2007.*Spectral Galerkin Boundary Integral Equation Methods for Plasmonic Nano-Structures*, Kolloquium SFB 755, Universit\"at G\"ottingen, Jan 8, 2009.*Plane Wave Discontinuous Galerkin Methods*, Manchester Applied Mathematics Seminar, University of Manchester, UK, March 25, 2009.*Adaptive Sparse Tensor Product Methods for Radiative Transfer*, Kolloquium of SFB 611, University of Bonn, Germany, May 19, 2009.*Sparse Adaptive Finite Elements for Radiative Transfer*, Seminar, ZIB Berlin, January, 2010.*Trefftz-DG methods*, Talk at University of Reading as part of the steering committee meeting of the project on Boundary Integral Equation Methods for High Frequency Scattering Problems, June 7, 2010.*Discrete Potentials and Discrete Compactness*, Seminar, Department of Mathematics, Brunel University, June 10, 2010.*Sparse Adaptive Finite Elements for Radiative Transfer*, Mathematics Colloquium, Jacobs University Bremen, Bremen, Germany, September 6, 2010.*Multiple Trace Boundary Integral Formulation for Helmholtz Transmission Problems*, Miniworkshop Numerische Mathematik, TU Graz, Austria, March 10, 2011.*Multiple Traces Boundary Integral Formulation for Helmholtz Transmission Problems*, Seminaire de Institut Mathematique de Toulouse, June 7, 2011.*Continuous and Discrete Helmholtz-type Decompositions*, Schwerpunktskolloquium Analysis und Numerik, Fachbereich Mathematik und Statistik, Universität Konstanz, Oct 18, 2012*Multiple Point Evaluation on Combined Tensor Product Supports*, MATHICSE Seminar, EPFL Lausanne, Dec 7, 2012.*Sparse Tensor Edge Elements*, Seminar presentation at Laboratoire Jacques-Louis Lions, Universite Marie et Pierre Curie, Paris VI, Feb 28, 2013.*Discretization of Advection-Diffusion of Magnetic Fields*, Mathematikkolloquium, Institut für Mathematik, Universität Innsbruck, June 25, 2013.*Boundary Integral Equations on Complex Screens*, Runge-Herglotz-Seminar über Angewandte Analysis, Universität Göttingen, January 6, 2014.*Plane Wave Discontinuous Galerkin Methods*, Seminar des Schwerpunkts "Partielle Differentialgleichungen", KIT Karlsruhe, Jan 9, 2014.*Shape Calculus and Shape Optimzation*, ShuRen Forum Talk, South University of Science and Technology of China (SUSTC), Shenzhen, China, May 29, 2015*Discretizing the Advection of Differential Forms*, Mathematics Colloquium, The Chinese University of Hong Kong, Hong Kong, June 1, 2015*Discretization of Advection-Diffusion of Magnetic Fields*, BCSRC Seminar Beijing Computational Science Research Center Beijing, China, June 4, 2015-
*Plane Wave Discontinuous Galerkin Methods*, Seminar Talk, Institute of Computational Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing, China, June 5, 2015 -
*Auxiliary Space Preconditioning for Variational Problems in H(curl)*, Kolloquium f¨r Angewandte Mathematik, TU Hamburg-Harburg, Hamburg, Germany, Jan 28, 2016. -
*Maxwell's Equations and the Hodge-Laplacian*, , Fakultätskolloquium der Technischen Fakultät, Christian-Albrechts Universität zu Kiel, Jan 29, 2016. -
*Multi-trace Boundary Integral Equations*, Computational Engineering Seminar Talk, Universität Darmstadt, May 9, 2016. -
*Multi-trace boundary integral formulations*, , S\'eminaire de Math\'ematiques Appliqu\'ees , College De France, Paris, March 3, 2017. -
*Exterior Shape Calculus*, Seminaire EDP-AN and MF, Universite de Nice Sophia-Antipolis, Nice, June 8, 2017. -
*Shape Differentiation: New Perspectives*, Kolloquium des Departements Mathematik, Universität Erlangen-Nürnberg, June 20, 2017. -
*Shape Differentiation: New Perspectives*, Seminarvortrag, Institut für Mathematik, Universität Tübingen, July 6, 2017. -
*Shape Differentiation: New Perspectives*, Talk in Fakultätskolloquium Mathematik, TU München, Nov 15, 2017. -
*Boundary Integral Equations on Complex Screens*, Mathematics Colloquium, University of Maryland, April 30, 2019. *Operator Preconditioning*,**Aziz Lecture**, university of Maryland, May 1, 2019.*Approximation of Shape Gradients*,**Applied Mathematics Seminar**, School of Mathematics and Actuarial Science, University of Leicester, UK, October 15, 2020.*The Topology of Circuit-Field Coupling*,**Mathematics Colloquium**, University of Illinois, October 22, 2020 (online)*Operator Preconditioning (OPC)*, One-World Numerical Analysis (OWNA)} Seminar Series October 4, 2021 on ZOOM, Link.-
*Adaptive Approximation of Shapes*, Seminar in Numerical Analysis, Universität Basel, April 8, 2022.

*Algorithmische Topologie für die Automobilindustrie*, Schülervortrag am Schnuppertag der Universität Bonn, 11. April 2002*Numerische Quadratur*, Probevorlesung im Rahmen der Maturandentage 2003, 10.9.2003*Algorithmic Topology for Car Manufacturing*, Vortrag vor Studentendelegation aus Athen, 1. April 2004, ETH Höngerberg*Topologie im industriellen Einsatz*, Öffentlicher Vortrag im Rahmen der Reihe "150 ETH Professoren im Gespräch" zum Jubiläum ETH 150, April 2005*Gewöohnliche Differentialgleichungen: Anschauliche Numerik*, HSGYM Hochschultag der Züricher Mittelschulen 2015, Feb 29, 2015, ETH Zurich.