Linear iterations as smoothers in multigrid methods: Theory with applications to incomplete decompositions. - Gabriel Wittum (IMPACT Comput. Sci. Eng., 1989)

A multigrid method for the computation of eigenmodes of closed water basins. - Stefan A. Sauter; Gabriel Wittum (IMPACT Comput. Sci. Eng., 1992)

Parallel Frequency Filtering. - W. Weiler; Gabriel Wittum (Computing, 1997)

Additive and Multiplicative Multi-Grid - A Comparison. - Peter Bastian; Wolfgang Hackbusch; Gabriel Wittum (Computing, 1998)

Robust Schur complement method for strongly anisotropic elliptic equations. - Boris N. Khoromskij; Gabriel Wittum (Numer. Linear Algebra Appl., 1999)

An asymptotically optimal Schur complement reduction for the Stokes equation. - Boris N. Khoromskij; Gabriel Wittum (Numerische Mathematik, 1999)

Frequency Filtering for Elliptic Interface Problems with Lagrange Multipliers. - Boris N. Khoromskij; G. E. Mazurkevich; Gabriel Wittum (SIAM J. Sci. Comput., 1999)

Homogenization and Multigrid. - Nicolas Neuss; Willi Jäger; Gabriel Wittum (Computing, 2001)

Asymptotically exact a posteriori estimators for the pointwise gradient error on each element in irregular meshes. Part 1: A smooth problem and globally quasi-uniform meshes. - Wolfgang Hoffmann; Alfred H. Schatz; Lars B. Wahlbin; Gabriel Wittum (Math. Comput., 2001)

Parallel adaptive multigrid algorithm for 2-d 3-t diffusion equations. - Zeyao Mo; Longjun Shen; Gabriel Wittum (Int. J. Comput. Math., 2004)

Coarse Graining for Upscaling of Flow in Heterogeneous Porous Media. - Jens P. Eberhard; Sabine Attinger; Gabriel Wittum (Multiscale Model. Simul., 2004)

Two-frequency decomposition. - A. Buzdin; Gabriel Wittum (Numerische Mathematik, 2004)

Numerical Solution of Elliptic Differential Equations by Reduction to the Interface. - Boris N. Khoromskij; Gabriel Wittum (Springer, 2004)

Large-scale density-driven flow simulations using parallel unstructured Grid adaptation and local multigrid methods. - Stefan Lang 002; Gabriel Wittum (Concurr. Pract. Exp., 2005)

Nonlinear anisotropic diffusion filtering of three-dimensional image data from two-photon microscopy. - Philip Julian Broser; Roland Schulte; Arnd Roth; Fritjof Helmchen; Jack Waters; Stefan Lang 002; Bert J. Sakmann; Gabriel Wittum (Image Processing: Algorithms and Systems, 2006)

NeuGen: A tool for the generation of realistic morphology of cortical neurons and neural networks in 3D. - Jens P. Eberhard; Alexander Wanner; Gabriel Wittum (Neurocomputing, 2006)

On the influence of different stabilisation methods for the incompressible Navier-Stokes equations. - Sandra Nägele; Gabriel Wittum (J. Comput. Phys., 2007)

Low Machnumber aeroacoustics - A direct one-grid approach. - Achim Gordner; Gabriel Wittum (J. Num. Math., 2007)

Efficient Hierarchical Approximation of High-Dimensional Option Pricing Problems. - Christoph Reisinger; Gabriel Wittum (SIAM J. Sci. Comput., 2007)

Numerical upscaling for the eddy-current model with stochastic magnetic materials. - Jens P. Eberhard; Dan Popovic; Gabriel Wittum (J. Comput. Phys., 2008)

IBLU decompositions based on Padé approximants. - A. Buzdin; Dmitriy Logashenko; Gabriel Wittum (Numer. Linear Algebra Appl., 2008)

Calculation of default probability (PD) solving Merton Model PDEs on sparse grids. - Philipp Schroeder 001; Gabriel Wittum (IPDPS, 2009)

Efficient multigrid solver for the 3D random walker algorithm. - Xin Wang; Tobias Heimann; Arne Nägel; Gabriel Wittum; Hans-Peter Meinzer (Image Processing, 2009)

The Tree-Edit-Distance, a Measure for Quantifying Neuronal Morphology. - Holger Heumann; Gabriel Wittum (Neuroinformatics, 2009)

Scalable Heuristic Algorithms for the Parallel Execution of Data Flow Acyclic Digraphs. - Zeyao Mo; Aiqing Zhang; Gabriel Wittum (SIAM J. Sci. Comput., 2009)

Software Framework UG: Parallel Simulation of a Three-Dimensional Benchmark Problem for Thermohaline-Driven Flow. - Michael Lampe; Alfio Grillo; Gabriel Wittum (High Performance Computing in Science and Engineering, 2010)

Three-dimensional simulation of the thermohaline-driven buoyancy of a brine parcel. - Alfio Grillo; Michael Lampe; Gabriel Wittum (Comput. Vis. Sci., 2010)

A generalization of the vertex-centered finite volume scheme to arbitrary high order. - Andreas Vogel 001; Jinchao Xu; Gabriel Wittum (Comput. Vis. Sci., 2010)

A three-dimensional mathematical model of active signal processing in axons. - Konstantinos Xylouris; Gillian Queisser; Gabriel Wittum (Comput. Vis. Sci., 2010)

Coarse Graining on Arbitrary Grids. - Ivo Muha; Sabine Stichel; Sabine Attinger; Gabriel Wittum (Multiscale Model. Simul., 2010)

A method to investigate the diffusion properties of nuclear calcium. - Gillian Queisser; Gabriel Wittum (Biol. Cybern., 2011)

Inertia based filtering of high resolution images using a GPU cluster. - Daniel Jungblut; Gillian Queisser; Gabriel Wittum (Comput. Vis. Sci., 2011)

Finite dose skin penetration: a comparison of concentration-depth profiles from experiment and simulation. - Arne Nägel; Tsambika Hahn; Ulrich F. Schäfer; Claus-Michael Lehr; Michael Heisig; Gabriel Wittum (Comput. Vis. Sci., 2011)

Forchheimer's correction in modelling flow and transport in fractured porous media. - Alfio Grillo; Dmitriy Logashenko; Sabine Stichel; Gabriel Wittum (Comput. Vis. Sci., 2012)

Preparation of grids for simulations of groundwater flow in fractured porous media. - Sebastian Reiter 002; Dmitriy Logashenko; Alfio Grillo; Gabriel Wittum (Comput. Vis. Sci., 2012)

Editorial. - Gabriel Wittum (Comput. Vis. Sci., 2012)

Convergence and optimality of adaptive edge finite element methods for time-harmonic Maxwell equations. - Liuqiang Zhong; Long Chen 002; Shi Shu; Gabriel Wittum; Jinchao Xu (Math. Comput., 2012)

Visual reflection library: a framework for declarative GUI programming on the Java platform. - Michael Hoffer; Christian Poliwoda; Gabriel Wittum (Comput. Vis. Sci., 2013)

A massively parallel geometric multigrid solver on hierarchically distributed grids. - Sebastian Reiter 002; Andreas Vogel 001; Ingo Heppner; Martin Rupp; Gabriel Wittum (Comput. Vis. Sci., 2013)

UG 4: A novel flexible software system for simulating PDE based models on high performance computers. - Andreas Vogel 001; Sebastian Reiter 002; Martin Rupp; Arne Nägel; Gabriel Wittum (Comput. Vis. Sci., 2013)

Catwalk: A Quick Development Path for Performance Models. - Felix Wolf 001; Christian H. Bischof; Torsten Hoefler; Bernd Mohr; Gabriel Wittum; Alexandru Calotoiu; Christian Iwainsky; Alexandre Strube; Andreas Vogel 001 (Euro-Par Workshops (2), 2014)

Synaptic bouton properties are tuned to best fit the prevailing firing pattern. - Markus M. Knodel; Romina Geiger; Lihao Ge; Daniel Bucher; Alfio Grillo; Gabriel Wittum; Christoph Schuster; Gillian Queisser (Frontiers Comput. Neurosci., 2014)

Models and simulations of variable-density flow in fractured porous media. - Sebastian Reiter 002; Dmitriy Logashenko; Sabine Stichel; Gabriel Wittum; Alfio Grillo (Int. J. Comput. Sci. Eng., 2014)

10, 000 Performance Models per Minute - Scalability of the UG4 Simulation Framework. - Andreas Vogel 001; Alexandru Calotoiu; Alexandre Strube; Sebastian Reiter 002; Arne Nägel; Felix Wolf 001; Gabriel Wittum (Euro-Par, 2015)

Utilization of empirically determined energy-optimal CPU-frequencies in a numerical simulation code. - Björn Dick; Andreas Vogel 001; Dmitry Khabi; Martin Rupp; Uwe Küster; Gabriel Wittum (Comput. Vis. Sci., 2015)

Parallel tensor sampling in the hierarchical Tucker format. - Lars Grasedyck; Ronald Kriemann; Christian Löbbert; Arne Nägel; Gabriel Wittum; Konstantinos Xylouris (Comput. Vis. Sci., 2015)

Adaptive large eddy simulation. - A. Hauser; Gabriel Wittum (Comput. Vis. Sci., 2015)

Multigrid analysis of spatially resolved hepatitis C virus protein simulations. - Markus M. Knodel; Arne Nägel; Sebastian Reiter 002; Martin Rupp; Andreas Vogel 001; Paul Targett-Adams; Eva Herrmann; Gabriel Wittum (Comput. Vis. Sci., 2015)

Numerical simulation of skin transport using Parareal. - Andreas Kreienbuehl; Arne Nägel; Daniel Ruprecht; Robert Speck; Gabriel Wittum; Rolf Krause (Comput. Vis. Sci., 2015)

Scalable shape optimization methods for structured inverse modeling in 3D diffusive processes. - Arne Nägel; Volker Schulz 001; Martin Siebenborn; Gabriel Wittum (Comput. Vis. Sci., 2015)

Editorial: Algorithmic requirements for HPC. - Gabriel Wittum (Comput. Vis. Sci., 2015)

Parareal convergence for 2D unsteady flow around a cylinder. - Andreas Kreienbuehl; Arne Nägel; Daniel Ruprecht; Andreas Vogel 001; Gabriel Wittum; Rolf Krause (CoRR, 2015)

A three-dimensional mathematical model for the signal propagation on a neuron's membrane. - Konstantinos Xylouris; Gabriel Wittum (Frontiers Comput. Neurosci., 2015)

Numerical simulation of contaminant transport in groundwater using software tools of (r^3t ). - Peter Frolkovic; Michael Lampe; Gabriel Wittum (Comput. Vis. Sci., 2016)

Space and Time Parallel Multigrid for Optimization and Uncertainty Quantification in PDE Simulations. - Lars Grasedyck; Christian Löbbert; Gabriel Wittum; Arne Nägel; Volker Schulz 001; Martin Siebenborn; Rolf Krause; Pietro Benedusi; Uwe Küster; Björn Dick (Software for Exascale Computing, 2016)

Automated Performance Modeling of the UG4 Simulation Framework. - Andreas Vogel 001; Alexandru Calotoiu; Arne Nägel; Sebastian Reiter 002; Alexandre Strube; Gabriel Wittum; Felix Wolf 001 (Software for Exascale Computing, 2016)

Automatic Performance Modeling of HPC Applications. - Felix Wolf 001; Christian H. Bischof; Alexandru Calotoiu; Torsten Hoefler; Christian Iwainsky; Grzegorz Kwasniewski; Bernd Mohr; Sergei Shudler; Alexandre Strube; Andreas Vogel 001; Gabriel Wittum (Software for Exascale Computing, 2016)

Virtual reality in advanced medical immersive imaging: a workflow for introducing virtual reality as a supporting tool in medical imaging. - Markus M. Knodel; Babett Lemke; Michael Lampe; Michael Hoffer; Clarissa Gillmann; Michael Uder; Jens Hillengaß; Gabriel Wittum; Tobias Bäuerle (Comput. Vis. Sci., 2018)

Solution of the 3D density-driven groundwater flow problem with uncertain porosity and permeability. - Alexander Litvinenko; Dmitriy Logashenko; Raúl Tempone; Gabriel Wittum; David E. Keyes (CoRR, 2019)

Rotational test spaces for a fully-implicit FVM and FEM for the DNS of fluid-particle interaction. - Susanne Höllbacher; Gabriel Wittum (J. Comput. Phys., 2019)

3d Modeling and simulation of a harpsichord. - Lukas Larisch; Babett Lemke; Gabriel Wittum (Comput. Vis. Sci., 2020)

Mesh generation for thin layered domains and its application to parallel multigrid simulation of groundwater flow. - Sebastian Reiter 002; Dmitry Logashenko; Andreas Vogel 001; Gabriel Wittum (Comput. Vis. Sci., 2020)

Automated methods for the comparison of natural languages. - Gabriel Wittum; Michael Hoffer; Babett Lemke; Robert Jabs; Arne Nägel (Comput. Vis. Sci., 2020)

Performance comparisons of geometric multigrid solvers and balancing domain decomposition solvers. - Hongjie Zheng; Ryuji Shioya; Hiroshi Kawai; Sebastian Reiter 002; Gabriel Wittum (Comput. Vis. Sci., 2020)

Gradient-consistent enrichment of finite element spaces for the DNS of fluid-particle interaction. - Susanne Höllbacher; Gabriel Wittum (J. Comput. Phys., 2020)

A sharp interface method using enriched finite elements for elliptic interface problems. - Susanne Höllbacher; Gabriel Wittum (Numerische Mathematik, 2021)

Correction to: A sharp interface method using enriched finite elements for elliptic interface problems. - Susanne Höllbacher; Gabriel Wittum (Numerische Mathematik, 2021)

Influence of T-Bar on Calcium Concentration Impacting Release Probability. - Markus M. Knodel; Ranjita Dutta Roy; Gabriel Wittum (Frontiers Comput. Neurosci., 2022)

Uncertainty quantification in coastal aquifers using the multilevel Monte Carlo method. - Alexander Litvinenko; Dmitry Logashenko; Raúl Tempone; Ekaterina Vasilyeva; Gabriel Wittum (CoRR, 2023)

Estimation of uncertainties in the density driven flow in fractured porous media using MLMC. - Dmitry Logashenko; Alexander Litvinenko; Raúl Tempone; Gabriel Wittum (CoRR, 2024)

Uncertainty quantification in the Henry problem using the multilevel Monte Carlo method. - Dmitry Logashenko; Alexander Litvinenko; Raúl Tempone; Ekaterina Vasilyeva; Gabriel Wittum (J. Comput. Phys., 2024)

Modelling Human Skin Morphology and Simulating Transdermal Transport of 50 Chemicals. - Milana Tesfamarian; Arne Nägel; Michael Heisig; Gabriel Wittum (CoRR, 2025)