Mathematisch-Naturwissenschaftliche Fakultät: Mathematisch-Naturwissenschaftliche Fakultät: Neuzugänge
Anzeige der Dokumente 541-560 von 5046
-
3D incompressible two-phase flow benchmark computations for rising droplets
(2014-03)We perform 3D incompressible two-phase flow simulations of rising droplets. Based on a similar 2D benchmark, a 3D benchmark configuration with two test cases is formulated in which we compare the flow solvers DROPS, NaSt3DGPF ... -
Stable splitting of polyharmonic operators by generalized Stokes systems
(2015-12)A stable splitting of 2<em>m</em>-th order elliptic partial differential equations into 2(<em>m</em>−1) problems of Poisson type and one generalized Stokes problem is established for any space dimension <em>d</em> ≥ 2 and ... -
A new discretization for mth-Laplace equations with arbitrary polynomial degrees
(2016-07)This paper introduces new mixed formulations and discretizations for <em>m</em>th-Laplace equations of the form (−1)<em><sup>m</sup></em>∆<em><sup>m</sup>u</em> = f for arbitrary <em>m</em> = 1, 2, 3, . . . based on novel ... -
On the stability of the Rayleigh-Ritz method for eigenvalues
(2017-01-05)This paper studies global stability properties of the Rayleigh-Ritz approximation of eigenvalues of the Laplace operator. The focus lies on the ratios <em>^λ<sub>k</sub></em>/<em>λ<sub>k</sub></em> of the <em>k</em>th ... -
Multiscale Petrov-Galerkin method for high-frequency heterogeneous Helmholtz equations
(2015-12)This paper presents a multiscale Petrov-Galerkin finite element method for time-harmonic acoustic scattering problems with heterogeneous coefficients in the high-frequency regime. We show that the method is pollution-free ... -
A multilevel approach to the evolutionary generation of polycrystalline structures
(2015-11)The Poisson-Voronoi tesselation is commonly used as an approximation to the microstructure of polycrystalline material. Although simple, this approximation fails to respect basic physical properties observed empirically, ... -
Convergence of nonsmooth descent methods via Kurdyka–Lojasiewicz inequality on Riemannian manifolds
(2015-11)We develop a subgradient-oriented descent method in nonsmooth optimization on Riemannian manifolds and prove convergence of the method in the sense of subsequences for nonsmooth functions whose standard models are strict. ... -
Generalized finite element methods for quadratic eigenvalue problems
(2015-10)We consider a large-scale quadratic eigenvalue problem (QEP), formulated using P1 finite elements on a fine scale reference mesh. This model describes damped vibrations in a structural mechanical system. In particular we ... -
Complexity of hierarchical refinement for a class of admissible mesh configurations
(2015-09)An adaptive isogeometric method based on <em>d</em>-variate hierarchical spline constructions can be derived by considering a refine module that preserves a certain class of admissibility between two consecutive steps of ... -
Regularized kernel based reconstruction in generalized Besov spaces
(2015)We present a theoretical framework for reproducing kernel based reconstruction methods in certain generalized Besov spaces based on positive, essentially self-adjoint operators. An explicit representation of the reproducing ... -
A generalized multiscale finite element method for poroelasticity problems I: linear problems
(2015-04)In this paper, we consider the numerical solution of poroelasticity problems that are of Biot type and develop a general algorithm for solving coupled systems. We discuss the challenges associated with mechanics and flow ... -
CLSVOF as a fast and mass-conserving extension of the level-set method for the simulation of two-phase flow problems
(2015-07)The modeling of two-phase flows in computational fluid dynamics is still an area of active research. One popular method is the coupling of level-set and volume-of-fluid (CLSVOF), which benefits from the advantages of both ... -
Note on “The smooting effect of integration in ℝd and the ANOVA decomposition”
(2015)This is a note on [Math. Comp. <b>82</b>, 383–400 (2013)]. We first report a mistake, in that the main result Theorem 3.1, though correct, does not as claimed apply to the Asian option pricing problem. This is because ... -
A sparse grid based method for generative dimensionality reduction of high-dimensional data
(2015-11)Generative dimensionality reduction methods play an important role in machine learning applications because they construct an explicit mapping from a low-dimensional space to the high-dimensional data space. We discuss a ... -
Reproducing kernel Hilbert spaces for parametric partial differential equations
(2015-06)In this article, we present kernel methods for the approximation of quantities of interest which are derived from solutions of parametric partial differential equations. We explicitly construct a reproducing kernel Hilbert ... -
Subspace correction methods in algebraic multi-level frames
(2015-06)This study aims at introducing new algebraic multi-level solution techniques for linear systems with M-matrices. Previous optimal geometric constructions by multi-level generating systems or multi-level frames are adapted. ... -
On tensor product approximation of analytic functions
(2015)We prove sharp, two-sided bounds on sums of the form ∑<em><sub>k∈ℕ<sup>d</sup><sub>0</sub></em><sub>\<em>𝒟<sub>a</sub></em>(<em>T</em>)</sub></sub> exp(− ∑<em><sup>d</sup><sub>j</em><sub>=1</sub></sub> ... -
Variational multiscale stabilization and the exponential decay of fine-scale correctors
(2015-05)This paper reviews the variational multiscale stabilization of standard finite element methods for linear partial differential equations that exhibit multiscale features. The stabilization is of Petrov-Galerkin type with ... -
Geographie und Recht: Gerichtsverfahren und ihre Relevanz für studying-up power bei der Kriminalitäts- und Terrorismusbekämpfung
(2023)Sarah Klosterkamp will in diesem Buch erstens bereits bestehende gerichtsethnographische Methoden für eine Humangeographie fruchtbar machen, die an Recht und seinen multiplen Wechselwirkungen im Sinne von Subjektkonstitutionen ... -
3D Analysis-suitable T-splines: definition, linear independence and m-graded local refinement
(2016-01)This paper addresses the linear independence of T-splines in three space dimensions. We give an abstract definition of analysis-suitability, and prove that it is equivalent to dual-compatibility, wich guarantees linear ...
