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Workshop Programme ⇥⇤⌅⇧⇥⌃⇤⌥⇥⌃ ⌦↵✏⌦⇣ ⇧⌘✓◆ ⌫ ⌅⇧⌥⇠⌃ ⌦⇡⌅⇤◆⇢✓⌦⇧⌦ ⌧⌥◆⌅⇧⇧⌫⌃⇥⇠⌅⌦⌫ ⇤⌅⇧✓ ⇣ !⌦⌧ ⌅⌥⇢⌅ "⌅⇧!⌦# ⌅⇠⌅⌫ "⌅⇧⌦$%!⌦&'$( Organized by Peter Bastian, Hester Bijl, Christian Klingenberg and Barbara Wohlmuth. We would like to thank Ingrid Hellwig and Ole Klein for their help with the preparation of the workshop. This workshop is supported financally by the DFG Priority Programme 1648 “Software for Exascale Computing” as well as the “Heidelberg Graduate School of Mathematical and Computational Methods for the Sciences”. Contents 1Schedule 4 2InvitedTalks 7 2.1 Assyr Abdulle: Multiscale and reduced order modeling methods for linear and non- linear homogenization problems . 7 2.2 Alexandre Ern: A nonintrusive Reduced Basis Method applied to aeroacoustic simu- lations............................................ 7 2.3 Robert D. Falgout: Multigrid Methods and Software for Exascale Computing . 8 2.4 MikeGiles:MultilevelMonteCarlomethods . 9 2.5 Mark Hoemmen: Getting the Right Answer Despite Incorrect Hardware . 9 2.6 Martin Kronbichler: Fast matrix-free methods for adaptive higher order elements . 10 2.7 Claus-Dieter Munz: High Order Schemes for Complex Flow Simulations . 11 2.8 Philip L. Roe: Reassessing Lax-Wendroffandsimilarschemes . 12 2.9 Chi-Wang Shu: Positivity-preserving high order schemes in CFD . 12 2.10 Carol S. Woodward: A Reconsideration of Fixed Point Methods for Nonlinear Systems 12 3 Contributed Talks 14 3.1 Juan A. Acebrón: Efficient parallel solution of the telegraph equations subject to general boundary conditions by a novel Monte Carlo metho . 14 3.2 Michael Bader: Petascale Earthquake Simulations with SeisSol . 15 3.3 Santiago Badia: A Highly Scalable Asynchronous Implementation of Balancing Do- mainDecompositionbyConstraints. 15 3.4 Martin Hanek: Numerical solution of Navier-Stokes equations using Balancing Domain DecompositionbyConstraints . 17 3.5 Mario Heene: Hierarchical Numerics for High-Dimensional Exascale Computing . 18 3.6 Verena Krupp: Exploiting modern HPC systems with hybrid parallelism in high order DG for linear equations . 18 3.7 Stéphane Lanteri: High performance discontinuous finite element time-domain solvers for computational nanophotonics . 19 3.8 Martin Lanser: A massively parallel domain decomposition / AMG method for elas- ticity problems . 20 3.9 René Milk: Scalable, Hybrid-Parallel Multiscale Methods using DUNE . 21 3.10 Miriam Mehl: Recent Advances in Parallel Fluid-Structure-Acoustics Simulations . 21 3.11 Eike Hermann Müller: Performance portable multigrid preconditioners for mixed finite element discretisations in atmospheric models . 22 3.12 Steffen Müthing: Efficient Discontinuous Galerkin schemes on hybrid HPC architectures 23 3.13 Hannah Rittich: Local Fourier Analysis of Pattern Structured Operators . 23 3.14 D. G. Roehm: Parallel Runtime Environments with Cloud Database: A Performance Study for the Heterogeneous Multiscale Method with Adaptive Sampling . 24 3.15 Jonatan Nunez-de la Rosa: Higher-Order Discontinuous Galerkin Spectral Element MethodsforComputationalAstrophysics . 25 1 3.16 Daniel Ruprecht: The parallel-in-time methods Parareal and PFASST: Library devel- opment and applications . 26 3.17 Gero Schnücke: Towards a high order moving grid method for compressible flow equa- tions............................................. 26 3.18 Martin Siebenborn: Structured inverse modeling in diffusiveprocesses . 27 3.19 JonasThies: A3D-parallelinterioreigenvaluesolver. 27 3.20 Christian Waluga: Physics-aware solver concepts for geophysical applications on mas- sively parallel architectures . 28 3.21 Peter Zaspel: Optimal parallel uncertainty quantification in large-scale flow problems 28 4 Important Information 30 4.1 Places ............................................ 30 4.2 PublicTransport ...................................... 30 5ListofParticipants 32 2 1Schedule The workshop is taking place in room 432 on the fourth floor of building 368 on the “Neuenheimer Feld” campus of Heidelberg University. For information on how to get there see chapter 4 of this document. Coffee breaks are in the “common room” on fifth floor. Monday, December 1, 2014 08:50 - 09:20 Registration 09:20 - 09:30 Opening Abstract 09:30 - 10:20 Robert D. Falgout (Livermore) Multigrid Methods and Software for Exascale Computing page 8 10:20 - 10:45 Eike Hermann Müller (Bath) Performance portable multigrid preconditioners for mixed finite el- page 22 ement discretisations in atmospheric models 10:45-11:15 Coffee break 11:15 - 11:40 Christian Waluga (München) Physics-aware solver concepts for geophysical applications on mas- page 28 sively parallel architectures 11:40 - 12:05 Daniel Ruprecht (Lugano) The parallel-in-time methods Parareal and PFASST: Library de- page 26 velopment and applications 12:05 - 12:30 Hannah Rittich (Wuppertal) Local Fourier Analysis of Pattern Structured Operators page 23 12:30 - 14:00 Lunch break (Mensa) 14:00 - 14:50 Mike Giles (Oxford) Multilevel Monte Carlo methods page 9 14:50 - 15:15 Juan A. Acebrón (Lisbon) Efficient parallel solution of the telegraph equations subject to gen- page 14 eral boundary conditions by a novel Monte Carlo method 15:15 - 15:40 Peter Zaspel (Bonn) Optimal parallel uncertainty quantification in large-scale flow prob- page 28 lems 15:40-16:10 Coffee break 16:10 - 17:00 Assyr Abdulle (Lausanne) Multiscale and reduced order modeling methods for linear and non- page 7 linear homogenization problems 17:00 - 17:25 René Milk (Münster) Hybrid-Parallel Multiscale Methods using DUNE page 21 17:25 - 17:50 D. G. Roehm (Stuttgart) Parallel Runtime Environments with Cloud Database: A Perfor- page 24 mance Study for the Heterogeneous Multiscale Method with Adap- tive Sampling 18:00 - 19:00 Math meets HPC: Get-together in common room (514, fifth floor) 3 Tuesday, December 2, 2014 09:00 - 09:50 Alexandre Ern (Paris) Abstract A nonintrusive Reduced Basis Method applied to aeroacoustic sim- page 7 ulations 09:50 - 10:15 Mario Heene (Stuttgart) Hierarchical Numerics for High-Dimensional Exascale Computing page 18 10:15 - 10:40 Martin Siebenborn (Trier) Structured inverse modeling in diffusiveprocesses page27 10:40-11:10 Coffee break 11:10 - 12:00 Claus-Dieter Munz (Stuttgart) High Order Schemes for Complex Flow Simulations page 11 12:00 - 12:25 Stéphane Lanteri (Sophia Antipolis) High performance discontinuous finite element time-domain solvers page 19 for computational nanophotonics 12:25 - 14:00 Lunch break (Mensa) 14:00 - 14:50 Martin Kronbichler (München) Fast matrix-free methods for adaptive higher order elements page 10 14:50 - 15:15 Jonatan Nunez-de la Rosa (Stuttgart) Higher-Order Discontinuous Galerkin Spectral Element Methods page 25 for Computational Astrophysics 15:15 - 15:40 Verena Krupp (Siegen) Exploiting modern HPC systems with hybrid parallelism in high page 18 order DG for linear equations 15:40 - 16:05 Steffen Müthing (Heidelberg) Efficient Discontinuous Galerkin schemes on hybrid HPC architec- page 23 tures 16:05-16:30 Coffee break 16:30 - 17:20 Mark Hoemmen (Albuquerque) Getting the Right Answer Despite Incorrect Hardware page 9 17:20 - 17:45 Jonas Thies (Köln) A3D-parallelinterioreigenvaluesolver page27 17:45 - 18:10 Martin Lanser (Köln) A massively parallel domain decomposition / AMG method for elas- page 20 ticity problems 19:30 Conference dinner (Wirtshaus “Zum Seppl”) 4 Wednesday, December 3, 2014 09:00 - 09:50 Philip L. Roe (Ann Arbor) Abstract Reassessing Lax-Wendroffand similar schemes page 12 09:50 - 10:15 Michael Bader (München) Petascale Earthquake Simulations with SeisSol] page 15 10:15 - 10:40 Miriam Mehl (Stuttgart) To Be Anounced page 21 10:40-11:10 Coffee break 11:10 - 12:00 Carol S. Woodward (Livermore) A Reconsideration of Fixed Point Methods for Nonlinear Systems page 12 12:00 - 12:25 Santiago Badia (Castelldefels) AHighlyScalableAsynchronousImplementationofBalancingDo- page 15 main Decomposition by Constraints 12:25 - 14:00 Lunch break (Mensa) 14:00 - 14:50 Chi-Wang Shu (Providence) Positivity-preserving high order schemes in CFD page 12 14:50 - 15:15 Martin Hanek (Prague) Numerical solution of Navier-Stokes equations using Balancing Do- page 17 main Decomposition by Constraints 15:15 - 15:40 Gero Schnücke (Würzburg) Towards a high order moving grid method for compressible flow page 26 equations 15:40 Final remarks and workshop end 5 2InvitedTalks 2.1 Multiscale and reduced order modeling methods for linear and nonlinear homogenization problems Assyr Abdulle Ecole Polytechnique Fédérale de Lausanne (EPFL) Station 8, CH-1015 Lausanne, Switzerland Abstract: In this talk we will present recent developments in the design and analysis of numerical homogenization methods. Numerical methods for linear and nonlinear partial differential equations that combine multiscale methods with reduced order modeling techniques such as the reduced basis method will be discussed. The talk is based upon a series of joint works with various collaborators[1,2,3,4,5]. [1] A. Abdulle and Y. Bai, Reduced basis finite element heterogeneous multiscale method for high-order discretizations of elliptic homogenization problems, J. Comput. Phys., vol. 191, num. 1, p. 18-39, 2012. [2] A. Abdulle and Y. Bai, Reduced order modelling numerical homogenization, Philosophical Transactions of the Royal Society A, vol. 372, num. 2021, 2014. [3] A. Abdulle, Y. Bai and G. Vilmart, Reduced basis finite element heterogeneous multiscale method for quasilinear elliptic homogenization problems, Discrete Contin. Dyn. Syst. vol.8, num. 1, 2015. [4] A. Abdulle and O. Budac, An adaptive finite element heterogeneous multiscale method for Stokes
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