Contact Information

Johann Rudi
Institute for Computational Engineering and Sciences (ICES)
The University of Texas at Austin
201 East 24th Street, Stop C0200
Austin, Texas 78712-1229, USA
Office: POB 4.230
E-mail: johann@ices.utexas.edu

Research Interests

Nonlinear Stokes Flow • Adaptive High-Order Finite Element and Discontinuous Galerkin Methods • Fast, Scalable Iterative Solvers for Nonlinear and Linear Systems • Multigrid and Multilevel Methods • High-Performance Computing and Scalable Parallel Algorithms • Inverse Problems • Earth's Mantle Flow, Rheology, and Plate Tectonics • Time-Frequency Signal Analysis with Hilbert-Huang Transform, Wavelet Transform, and Fourier Transform


Publications / Theses

[1]
Johann Rudi, Georg Stadler, and Omar Ghattas, Weighted BFBT Preconditioner for Stokes Flow Problems with Highly Heterogeneous Viscosity, SIAM Journal on Scientific Computing 39, 2017, pp. S272–S297. [arXiv | doi: 10.1137/16M108450X]

[2]
Johann Rudi, A. Cristiano I. Malossi, Tobin Isaac, Georg Stadler, Michael Gurnis, Peter W. J. Staar, Yves Ineichen, Costas Bekas, Alessandro Curioni, and Omar Ghattas, An Extreme-Scale Implicit Solver for Complex PDEs: Highly Heterogeneous Flow in Earth's Mantle, Winner of the ACM Gordon Bell Prize 2015, in SC '15: Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis, 2015. [pdf | doi: 10.1145/2807591.2807675 | visualization movie]

[3]
Hari Sundar, George Biros, Carsten Burstedde, Johann Rudi, Omar Ghattas, and Georg Stadler, Parallel Geometric-Algebraic Multigrid on Unstructured Forests of Octrees, in SC '12: Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis, 2012. [pdf | doi: 10.1109/SC.2012.91]

[4]
Johann Rudi, Ronald Pabel, Gabriela Jager, Robin Koch, Angela Kunoth, and Heye Bogena, Multiscale Analysis of Hydrologic Time Series Data Using the Hilbert-Huang Transform (HHT), Vadose Zone Journal 9, 2010, pp. 925–942. [pdf | doi: 10.2136/vzj2009.0163]

[5]
Johann Rudi, Empirical Mode Decomposition via adaptiver Wavelet-Approximation (German), Diploma Thesis, Universität Paderborn, Germany, 2010. [pdf]


Presentations

SIAM CSE17
Scalable Spectral-Geometric-Algebraic Multigrid and Schur Complement Preconditioning for Nonlinear, Multiscale, Heterogeneous Flow in Earth's Mantle, joint work with: Georg Stadler, A. Cristiano I. Malossi, Tobin Isaac, Michael Gurnis, Peter W. J. Staar, Yves Ineichen, Costas Bekas, Alessandro Curioni, and Omar Ghattas, SIAM Conference on Computational Science & Engineering (CSE17), Atlanta, Georgia, March 3, 2017. [slides | play recording | minisymposium info]
ISC 2016
An Extreme-Scale Implicit Solver for Complex PDEs: Hybrid Spectral-Geometric-Algebraic Multigrid for Highly Heterogeneous Flow in Earth's Mantle, joint work with: A. Cristiano I. Malossi, Tobin Isaac, Georg Stadler, Michael Gurnis, Peter W. J. Staar, Yves Ineichen, Costas Bekas, Alessandro Curioni, and Omar Ghattas, ISC 2016, Frankfurt, Germany, June 22, 2016. [slides]
SIAM PP16
Extreme-Scale Solver for Earth's Mantle – Spectral-Geometric-Algebraic Multigrid Methods for Nonlinear, Heterogeneous Stokes Flow, joint work with: A. Cristiano I. Malossi, Tobin Isaac, Georg Stadler, Michael Gurnis, Peter W. J. Staar, Yves Ineichen, Costas Bekas, Alessandro Curioni, and Omar Ghattas, SIAM Conference on Parallel Processing for Scientific Computing (PP16), Paris, France, April 13, 2016. [slides | minisymposium info]
mu-BFBT Preconditioner for Stokes Flow Problems with Highly Heterogeneous Viscosity, Student Paper Competition Winner, joint work with: Georg Stadler and Omar Ghattas, 14-th Copper Mountain Conference on Iterative Methods, Copper Mountain, Colorado, USA, March 24, 2016. [slides]
Scalable Parallel Solvers for Highly Heterogeneous Nonlinear Stokes Flow Discretized with Adaptive High-Order Finite Elements, 26-th Robert J. Melosh Medal Finalists Symposium, Duke University, Durham, North Carolina, USA, April 24, 2015. [slides]
SIAM CSE15
Scalable Parallel Solvers for Highly Heterogeneous Nonlinear Stokes Flow Discretized with Adaptive High-Order Finite Elements, joint work with: Tobin Isaac, Georg Stadler, Micheal Gurnis, and Omar Ghattas, SIAM Conference on Computational Science & Engineering (CSE15), Salt Lake City, Utah, USA, March 16, 2015. [poster]
SC14
Parallel High-Order Geometric Multigrid Methods on Adaptive Meshes for Highly Heterogeneous Nonlinear Stokes Flow Simulations of Earth's Mantle, Best Poster Award, joint work with: Hari Sundar, Tobin Isaac, Georg Stadler, Micheal Gurnis, and Omar Ghattas, SC '14: The International Conference for High Performance Computing, Networking, Storage and Analysis, New Orleans, Louisiana, USA, November 18, 2014. [poster]
Parallel High-Order Geometric Multigrid Methods on Adaptive Meshes for Highly Heterogeneous Nonlinear Stokes Flow Simulations of Earth’s Mantle, joint work with: Hari Sundar, Tobin Isaac, Georg Stadler, Micheal Gurnis, and Omar Ghattas, ICES Student Forum, Austin, Texas, USA, November 14, 2014. [poster]
SIAM AN14
Plate Boundary-Resolving Nonlinear Global Mantle Flow Simulations Using Parallel High-Order Geometric Multigrid Methods on Adaptive Meshes, joint work with: Hari Sundar, Tobin Isaac, Georg Stadler, Micheal Gurnis, and Omar Ghattas, 2014 SIAM Annual Meeting, Chicago, Illinois, USA, July 7, 2014. [slides | play recording | minisymposium info]
SIAM CSE13
Adaptive High-Order Methods for Nonlinear Stokes Problems Arising in Mantle Flow, joint work with: Carsten Burstedde, Omar Ghattas, Micheal Gurnis, Tobin Isaac, Georg Stadler, and Hari Sundar, SIAM Conference on Computational Science & Engineering (CSE13), Boston, Massachusetts, USA, February 26, 2013. [poster]
RRW09
Empirical Mode Decomposition durch adaptive Wavelet-Approximation (German), joint work with: Angela Kunoth, 19th Rhein-Ruhr-Workshop on Applied Analysis, Approximation Theory, CAGD and Numerical Mathematics, Mühlheim an der Ruhr, Germany, February 6, 2009. [slides]