124 citations · 193 across the 13 of their papers we have counts for
14 papers
Regularization and passivity-preserving model reduction of quasilinear magneto-quasistatic coupled problems
Johanna Kerler-Back, Timo Reis, Tatjana Stykel
We consider the quasilinear magneto-quasistatic field equations that arise in the simulation of low-frequency electromagnetic devices coupled to electrical circuits. Spatial discre…
Optimization on the symplectic Stiefel manifold: SR decomposition-based retraction and applications
Bin Gao, Nguyen Thanh Son, Tatjana Stykel
Numerous problems in optics, quantum physics, stability analysis, and control of dynamical systems can be brought to an optimization problem with matrix variable subjected to the s…
Symplectic eigenvalues of positive-semidefinite matrices and the trace minimization theorem
Nguyen Thanh Son, Tatjana Stykel
Symplectic eigenvalues are conventionally defined for symmetric positive-definite matrices via Williamson's diagonal form. Many properties of standard eigenvalues, including the tr…
Analysis of a quasilinear coupled magneto-quasistatic model: solvability and regularity of solutions
Ralph Chill, Timo Reis, Tatjana Stykel
We consider a~quasilinear model arising from dynamical magnetization. This model is described by a~magneto-quasistatic (MQS) approximation of Maxwell's equations. Assuming that the…
Passivity, Port-Hamiltonian Formulation and Solution Estimates for a Coupled Magneto-Quasistatic System
Timo Reis, Tatjana Stykel
We study a~quasilinear coupled magneto-quasistatic model from a~systems theoretic perspective.} First, by taking the injected voltages as input and the associated currents as outpu…
Energy-adaptive Riemannian optimization on the Stiefel manifold
Robert Altmann, Daniel Peterseim, Tatjana Stykel
This paper addresses the numerical solution of nonlinear eigenvector problems such as the Gross-Pitaevskii and Kohn-Sham equation arising in computational physics and chemistry. Th…
Geometry of the symplectic Stiefel manifold endowed with the Euclidean metric
Bin Gao, Nguyen Thanh Son, P. -A. Absil +1
The symplectic Stiefel manifold, denoted by , is the set of linear symplectic maps between the standard symplectic spaces and $\mathbb{R}^{2n}…
Symplectic eigenvalue problem via trace minimization and Riemannian optimization
Nguyen Thanh Son, P. -A. Absil, Bin Gao +1
We address the problem of computing the smallest symplectic eigenvalues and the corresponding eigenvectors of symmetric positive-definite matrices in the sense of Williamson's theo…
Riemannian Optimization on the Symplectic Stiefel Manifold
Bin Gao, Nguyen Thanh Son, P. -A. Absil +1
The symplectic Stiefel manifold, denoted by , is the set of linear symplectic maps between the standard symplectic spaces and $\mathbb{R}^{2n}…
Balanced truncation for parametric linear systems using interpolation of Gramians: a comparison of algebraic and geometric approaches
Nguyen Thanh Son, Pierre-Yves Gousenbourger, Estelle Massart +1
When balanced truncation is used for model order reduction, one has to solve a pair of Lyapunov equations for two Gramians and uses them to construct a reduced-order model. Althoug…
Balanced truncation model reduction for 3D linear magneto-quasistatic field problems
Johanna Kerler-Back, Tatjana Stykel
We consider linear magneto-quasistatic field equations which arise in simulation of low-frequency electromagnetic devices coupled to electrical circuits. A finite element discretiz…
Implicit Higher-Order Moment Matching Technique for Model Reduction of Quadratic-bilinear Systems
Mian Muhammad Arsalan Asif, Mian Ilyas Ahmad, Peter Benner +2
We propose a projection based multi-moment matching method for model order reduction of quadratic-bilinear systems. The goal is to construct a reduced system that ensures higher-or…
Pseudo-Optimal Reduction of Structured DAEs by Rational Interpolation
Philipp Seiwald, Alessandro Castagnotto, Tatjana Stykel +1
In this contribution, we extend the concept of inner product and pseudo-optimality to dynamical systems modeled by differential-algebraic equations…
Model Reduction of Descriptor Systems by Interpolatory Projection Methods
Serkan Gugercin, Tatjana Stykel, Sarah Wyatt
In this paper, we investigate interpolatory projection framework for model reduction of descriptor systems. With a simple numerical example, we first illustrate that employing subs…