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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Editorial. - Wittum, Gabriel (Comput. Vis. Sci., 2013)

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

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

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

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

Competence in High Performance Computing 2010 - Proceedings of an International Conference on Competence in High Performance Computing, Schloss Schwetzingen, Germany, June 2010. (Springer, 2012)

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

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

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

Editorial. - Wittum, Gabriel (Comput. Vis. Sci., 2010)

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

Editorial. - Wittum, Gabriel (Comput. Vis. Sci., 2010)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Homogenization and Multigrid. - Neuss, Nicolas; Jäger, Willi; Wittum, Gabriel (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. - Hoffmann, Wolfgang; Schatz, Alfred H.; Wahlbin, Lars B.; Wittum, Gabriel (Math. Comput., 2001)

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

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

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

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

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

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

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