Results 21 to 30 of about 13,905 (109)
Negativity‐preserving transforms of tuples of symmetric matrices
Proceedings of the London Mathematical Society, Volume 132, Issue 4, April 2026.Abstract Compared to the entrywise transforms which preserve positive semidefiniteness, those leaving invariant the inertia of symmetric matrices reveal a surprising rigidity. We first obtain the classification of negativity preservers by combining recent advances in matrix analysis with some novel arguments relying on well‐chosen test matrices, Sidon ...
Alexander Belton +3 more
wiley +1 more source
Mesh and Model Adaptivity for Multiscale Elastoplastic Models With Prandtl‐Reuss Type Material Laws
International Journal for Numerical Methods in Engineering, Volume 127, Issue 6, 30 March 2026.ABSTRACT Homogenization methods simulate heterogeneous materials like composites effectively, but high computational demands can offset their benefits. This work balances accuracy and efficiency by assessing model and discretization errors of the finite element method (FEM) through an adaptive numerical scheme.
Arnold Tchomgue Simeu +2 more
wiley +1 more source
International Journal of Robust and Nonlinear Control, Volume 36, Issue 5, Page 3047-3067, 25 March 2026.ABSTRACT This paper presents a robust control synthesis and analysis framework for nonlinear systems with uncertain initial conditions. First, a deep learning‐based lifting approach is proposed to approximate nonlinear dynamical systems with linear parameter‐varying (LPV) state‐space models in higher‐dimensional spaces while simultaneously ...
Sourav Sinha, Mazen Farhood
wiley +1 more source
Star flows: a characterization via Lyapunov functions
, 2020 We say that a differentiable flow or vector field $X$ is star on a compact invariant set $\Lambda$ of the Riemannian manifold M if there exist neighborhoods $\mathcal{U} \in \mathfrak{X}^1(M)$ of $X$ and $U \subset M$ of $\Lambda$ for which every closed ...
Salgado, Luciana Silva
core
Variational Modeling of Porosity Waves
Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 1, March 2026.ABSTRACT Mathematical models for finite‐strain poroelasticity in an Eulerian formulation are studied by constructing their energy‐variational structure, which gives rise to a class of saddle‐point problems. This problem is discretized using an incremental time‐stepping scheme and a mixed finite element approach, resulting in a monolithic, structure ...
Andrea Zafferi, Dirk Peschka
wiley +1 more source
Stability and Instability of Time‐Domain Boundary Element Methods for the Acoustic Neumann Problem
Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 1, March 2026.ABSTRACT This work presents a stable time‐domain boundary element method for the acoustic wave equation in three‐dimensional unbounded domains. Other formulations of time‐domain boundary element methods based on retarded potential operators are known to exhibit stability issues, which often hinder their use in industrial contexts.
Simon Schneider +4 more
wiley +1 more source
Journal of Geophysical Research: Solid Earth, Volume 131, Issue 3, March 2026.Abstract Clay‐rich soils and sediments are key components of near‐surface systems, influencing water retention, ion exchange, and structural stability. Their complex dielectric response under moist conditions arises from surface–ion electrostatics and diffuse double layers that govern transport and retention processes. This study explores the broadband
Felix Schmidt +5 more
wiley +1 more source
Osculating geometry and higher‐order distance Loci
Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.Abstract We discuss the problem of optimizing the distance function from a given point, subject to polynomial constraints. A key algebraic invariant that governs its complexity is the Euclidean distance degree, which pertains to first‐order tangency. We focus on the data locus of points possessing at least one critical point of the distance function ...
Sandra Di Rocco +2 more
wiley +1 more source
Solving the "Isomorphism of Polynomials with Two Secrets" Problem for all Pairs of Quadratic Forms [PDF]
, 2014 We study the Isomorphism of Polynomial (IP2S) problem with m=2 homogeneous quadratic polynomials of n variables over a finite field of odd characteristic: given two quadratic polynomials (a, b) on n variables, we find two bijective linear maps (s,t) such
Fouque, Pierre-Alain +2 more
core
Efficient Dynamics: Reduced‐Order Modeling of the Time‐Dependent Schrödinger Equation
Advanced Physics Research, Volume 5, Issue 2, February 2026.Reduced‐order modeling (ROM) approaches for the time‐dependent Schrödinger equation are investigated, highlighting their ability to simulate quantum dynamics efficiently. Proper Orthogonal Decomposition, Dynamic Mode Decomposition, and Reduced Basis Methods are compared across canonical systems and extended to higher dimensions.
Kolade M. Owolabi
wiley +1 more source