Results 11 to 20 of about 45,671 (275)

Lower bounds for Steklov eigenfunctions [PDF]

open access: yesPure and Applied Mathematics Quarterly, 2021
Let $(\Omega,g)$ be a compact, analytic Riemannian manifold with analytic boundary $\partial \Omega = M.$ We give $L^2$-lower bounds for Steklov eigenfunctions and their restrictions to interior hypersurfaces $H \subset \Omega^{\circ}$ in a geometrically
J. Galkowski, J. Toth
semanticscholar   +1 more source

On local and global structures of transmission eigenfunctions and beyond [PDF]

open access: yesJournal of Inverse and Ill-Posed Problems, 2020
The (interior) transmission eigenvalue problems are a type of non-elliptic, non-selfadjoint and nonlinear spectral problems that arise in the theory of wave scattering.
Hongyu Liu
semanticscholar   +1 more source

Data-driven discovery of Koopman eigenfunctions for control [PDF]

open access: yesMachine Learning: Science and Technology, 2017
Data-driven transformations that reformulate nonlinear systems in a linear framework have the potential to enable the prediction, estimation, and control of strongly nonlinear dynamics using linear systems theory.
E. Kaiser, J. Kutz, S. Brunton
semanticscholar   +1 more source

Optimal Construction of Koopman Eigenfunctions for Prediction and Control [PDF]

open access: yesIEEE Transactions on Automatic Control, 2018
This article presents a novel data-driven framework for constructing eigenfunctions of the Koopman operator geared toward prediction and control. The method leverages the richness of the spectrum of the Koopman operator away from attractors to construct ...
Milan Korda, I. Mezić
semanticscholar   +1 more source

Extended Dynamic Mode Decomposition with Learned Koopman Eigenfunctions for Prediction and Control [PDF]

open access: yesAmerican Control Conference, 2019
This paper presents a novel learning framework to construct Koopman eigenfunctions for unknown, nonlinear dynamics using data gathered from experiments. The learning framework can extract spectral information from the full non-linear dynamics by learning
C. Folkestad   +5 more
semanticscholar   +1 more source

Control of eigenfunctions on surfaces of variable curvature [PDF]

open access: yesJournal of The American Mathematical Society, 2019
We prove a microlocal lower bound on the mass of high energy eigenfunctions of the Laplacian on compact surfaces of negative curvature, and more generally on surfaces with Anosov geodesic flows.
S. Dyatlov, Long Jin, S. Nonnenmacher
semanticscholar   +1 more source

Nonradiating Sources and Transmission Eigenfunctions Vanish at Corners and Edges [PDF]

open access: yesSIAM Journal on Mathematical Analysis, 2018
We consider the inverse source problem of a fixed wavenumber: study properties of an acoustic source based on a single far- or near-field measurement. We show that nonradiating sources having a convex or non-convex corner or edge on their boundary must ...
Eemeli Blåsten
semanticscholar   +1 more source

Localization of eigenfunctions via an effective potential [PDF]

open access: yesCommunications in Partial Differential Equations, 2017
We consider the localization of eigenfunctions for the operator on a Lipschitz domain Ω and, more generally, on manifolds with and without boundary. In earlier work, two authors of the present paper demonstrated the remarkable ability of the landscape ...
D. Arnold   +4 more
semanticscholar   +1 more source

Comparison of Direct and Adjoint k and α-Eigenfunctions

open access: yesJournal of Nuclear Engineering, 2021
Modal expansions based on k-eigenvalues and α-eigenvalues are commonly used in order to investigate the reactor behaviour, each with a distinct point of view: the former is related to fission generations, whereas the latter is related to time. Well-known
Vito Vitali   +4 more
doaj   +1 more source

Scattering by Curvatures, Radiationless Sources, Transmission Eigenfunctions, and Inverse Scattering Problems [PDF]

open access: yesSIAM Journal on Mathematical Analysis, 2018
We consider several intriguingly connected topics in the theory of wave propagation: geometrical characterizations of radiationless sources, non-radiating incident waves and interior transmission eigenfunctions, and their applications to inverse ...
Eemeli Blåsten, Hongyu Liu
semanticscholar   +1 more source

Home - About - Disclaimer - Privacy