Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Johann Radon Institute for Computational and Applied MathematicsAT101 papers
- Austrian Academy of SciencesAT83 papers
- Deutsches Elektronen-Synchrotron DESYDE68 papers
- Centre National de la Recherche ScientifiqueFR64 papers
- Yukhnovskii Institute for Condensed Matter Physics of the National Academy of Sciences of UkraineUA57 papers
- Institute of PhysicsPL54 papers
- Polish Academy of SciencesPL52 papers
- University of ViennaAT42 papers
- Max Planck Institute of Microstructure PhysicsDE41 papers
- TU WienAT41 papers
- National Academy of Sciences of UkraineUA37 papers
- Universität InnsbruckAT36 papers
146 papers · 1 filter
Mixed Finite Elements for Geometrically Exact Beams using Discontinuous Rotations and Discrete Curvature
Alexander Humer, Ivo Steinbrecher, Astrid Pechstein
We propose a novel mixed finite-element formulation for geometrically exact (Simo--Reissner) beams that introduces the moment vector as additional independent field. The specific m…
Approximation of Functions: Optimal Sampling and Complexity
David Krieg, Mario Ullrich
We consider approximation or recovery of functions based on a finite number of function evaluations. This is a well-studied problem in optimal recovery, machine learning, and numer…
The star discrepancy of a union of randomly digitally shifted Korobov polynomial lattice point sets depends polynomially on the dimension
Josef Dick, Friedrich Pillichshammer
The star discrepancy is a quantitative measure of the uniformity of a point set in the unit cube. A central quantity of interest is the inverse of the star discrepancy, $N(\varepsi…
Product Of Exponentials (POE) Splines on Lie-Groups: Limitations, Extensions, and Application to SO(3) and SE(3)
Andreas Mueller
Existing methods for constructing splines and Bezier curves on a Lie group G involve repeated products of exponentials deduced from local geodesics, w.r.t. a Riemannian metric, or…
Partial-differential-algebraic equations of nonlinear dynamics by Physics-Informed Neural-Network: (I) Operator splitting and framework assessment
Loc Vu-Quoc, Alexander Humer
Several forms for constructing novel physics-informed neural-networks (PINN) for the solution of partial-differential-algebraic equations based on derivative operator splitting are…
On the power of adaption and randomization
David Krieg, Erich Novak, Mario Ullrich
We present bounds on the maximal gain of adaptive and randomized algorithms over non-adaptive, deterministic ones for approximating linear operators on convex sets. If the sets are…
A Posteriori Single- and Multi-Goal Error Control and Adaptivity for Partial Differential Equations
Bernhard Endtmayer, Ulrich Langer, Thomas Richter +2
This work reviews goal-oriented a posteriori error control, adaptivity and solver control for finite element approximations to boundary and initial-boundary value problems for stat…
An Inverse Problems Approach to Pulse Wave Analysis in the Human Brain
Lukas Weissinger, Simon Hubmer, Ronny Ramlau +1
Cardiac pulsations in the human brain have received recent interest due to their possible role in the pathogenesis of neurodegenerative diseases. Further interest stems from their…
IGA Using Offset-based Overlapping Domain Parameterizations
Somayeh Kargaran, Bert Jüttler, Thomas Takacs
Isogeometric analysis (IGA) is a numerical method that connects computer-aided design (CAD) with finite element analysis (FEA). In CAD the computational domain is usually represent…
On the power of iid information for linear approximation
Mathias Sonnleitner, Mario Ullrich
This survey is concerned with the power of random information for approximation in the (deterministic) worst-case setting, with special emphasis on information consisting of functi…
Imposing nonlocal boundary conditions in Galerkin-type methods based on non-interpolatory functions
Svajūnas Sajavičius, Thomas Takacs
The imposition of inhomogeneous Dirichlet (essential) boundary conditions is a fundamental challenge in the application of Galerkin-type methods based on non-interpolatory function…
Screw and Lie Group Theory in Multibody Dynamics -- Recursive Algorithms and Equations of Motion of Tree-Topology Systems
Andreas Mueller
Screw and Lie group theory allows for user-friendly modeling of multibody systems (MBS) while at the same they give rise to computationally efficient recursive algorithms. The inhe…
Screw and Lie Group Theory in Multibody Kinematics -- Motion Representation and Recursive Kinematics of Tree-Topology Systems
Andreas Mueller
After three decades of computational multibody system (MBS) dynamics, current research is centered at the development of compact and user friendly yet computationally efficient for…
Sampling recovery in and other norms
David Krieg, Kateryna Pozharska, Mario Ullrich +1
We study the recovery of functions in various norms, including with , based on function evaluations. We obtain worst case error bounds for general classes of…
Analysis and systematic discretization of a Fokker-Planck equation with Lorentz force
Vincent Bosboom, Herbert Egger, Matthias Schlottbom
The propagation of charged particles through a scattering medium in the presence of a magnetic field can be described by a Fokker-Planck equation with Lorentz force. This model is…
Infinite-dimensional integration and -approximation on Hermite spaces
Michael Gnewuch, Aicke Hinrichs, Klaus Ritter +1
We study integration and -approximation of functions of infinitely many variables in the following setting: The underlying function space is the countably infinite tensor prod…
New mixed finite elements for the discretization of piezoelectric structures or macro-fibre composites
Astrid Pechstein, Martin Meindlhumer, Alexander Humer
We propose a new three-dimensional formulation based on the mixed Tangential-Displacement Normal-Normal-Stress (TDNNS) method for elasticity. In elastic TDNNS elements, the tangent…
New lower bounds for the integration of periodic functions
David Krieg, Jan Vybiral
We study the integration problem on Hilbert spaces of (multivariate) periodic functions. The standard technique to prove lower bounds for the error of quadrature rules uses bump fu…
On uniqueness and stable estimation of multiple parameters in the Cahn-Hilliard equation
Aaron Brunk, Herbert Egger, Oliver Habrich
We consider the identifiability and stable numerical estimation of multiple parameters in a Cahn-Hilliard model for phase separation. Spatially resolved measurements of the phase f…
Exponential tractability of -approximation with function values
David Krieg, Pawel Siedlecki, Mario Ullrich +1
We study the complexity of high-dimensional approximation in the -norm when different classes of information are available; we compare the power of function evaluations with t…
A sharp upper bound for sampling numbers in
Matthieu Dolbeault, David Krieg, Mario Ullrich
For a class of complex-valued functions on a set , we denote by its sampling numbers, i.e., the minimal worst-case error on , measured in , that can be achi…
An approximate multi-patch space for isogeometric analysis with a comparison to Nitsche's method
Pascal Weinmüller, Thomas Takacs
We present an approximately -smooth multi-patch spline construction which can be used in isogeometric analysis (IGA). A key property of IGA is that it is simple to achieve hig…
Almost- splines: Biquadratic splines on unstructured quadrilateral meshes and their application to fourth order problems
Thomas Takacs, Deepesh Toshniwal
Isogeometric Analysis generalizes classical finite element analysis and intends to integrate it with the field of Computer-Aided Design. A central problem in achieving this objecti…
Tensor Deblurring and Denoising Using Total Variation
Fatoumata Sanogo, Carmeliza Navasca, Stefan Kindermann
We consider denoising and deblurring problems for tensors. While images can be discretized as matrices, the analogous procedure for color images or videos leads to a tensor formula…