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Related papers: Linear Independence of Time-Frequency Shifts?

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This paper examines linear independence of shearlet systems. This property has already been studied for wavelets and other systems such as, for instance, for Gabor systems. In fact, for Gabor systems this problem is commonly known as the…

Functional Analysis · Mathematics 2015-01-30 Jackie Ma , Philipp Petersen

We consider bounded extremum seeking controls for time-varying linear systems with uncertain coefficient matrices and measurement uncertainty. Using a new change of variables, Lyapunov functions, and a comparison principle, we provide…

Optimization and Control · Mathematics 2025-01-20 Frederic Mazenc , Michael Malisoff , Emilia Fridman

We study a parabolic free boundary problem, arising from a model for the propagation of equi-diffusional premixed flames with high activation energy. If an initial data is compactly supported, then the solution vanishes in a finite time,…

Analysis of PDEs · Mathematics 2019-11-19 Rubin Abrams , Sunhi Choi

We obtain the posterior distribution of a random process conditioned on observing the empirical frequencies of a finite sample path. We find under a rather broad assumption on the "dependence structure" of the process, {\em c.f.}…

Probability · Mathematics 2022-03-02 Wenqing Hu , Hong Qian

We study sharp frame bounds of Gabor systems over rectangular lattices for different windows and integer oversampling rate. In some cases we obtain optimality results for the square lattice, while in other cases the lattices optimizing the…

Functional Analysis · Mathematics 2025-04-28 Markus Faulhuber , Irina Shafkulovska

We investigate the completeness of Gabor systems with respect to several classes of window functions on rational lattices. Our main results show that the time-frequency shifts of every finite linear combination of Hermite functions with…

Mathematical Physics · Physics 2016-11-29 Karlheinz Gröchenig , Antti Haimi , José Luis Romero

We investigate a quantum mechanical system on a noncommutative space for which the structure constant is explicitly time-dependent. Any autonomous Hamiltonian on such a space acquires a time-dependent form in terms of the conventional…

Quantum Physics · Physics 2014-10-15 Sanjib Dey , Andreas Fring

Faraday rotation in a magnetoactive medium with time dependent dielectric permittivity tensor is analyzed through both its diagonal and non-diagonal elements. Continuous and pulse incident laser field cases are considered. In a continuous…

Optics · Physics 2018-01-17 Zhyrair Gevorkian , Vladimir Gasparian , Josh Lofy

This paper deals with stability of discrete-time switched linear systems whose all subsystems are unstable and the set of admissible switching signals obeys pre-specified restrictions on switches between the subsystems and dwell times on…

Systems and Control · Electrical Eng. & Systems 2021-11-11 Atreyee Kundu

This paper investigates oscillation-free stability conditions of numerical methods for linear parabolic partial differential equations with some example extrapolations to nonlinear equations. Not clearly understood, numerical oscillations…

Numerical Analysis · Mathematics 2017-01-18 R. Corban Harwood , Mitch Main

We derive the asymptotic distribution of ordinal-pattern frequencies under weak dependence conditions and investigate the long-run covariance matrix not only analytically for moving-average, Gaussian, and the novel generalized coin-tossing…

Statistics Theory · Mathematics 2025-07-24 Angelika Silbernagel , Christian Weiß

Physical systems with many degrees of freedom can often be understood in terms of transitions between a small number of metastable states. For time-homogeneous systems with short-term memory these transitions are fully characterized by a…

Molecular Networks · Quantitative Biology 2015-06-03 Nils B. Becker , Pieter Rein ten Wolde

This paper investigates the global stability and the global asymptotic stability independent of the sizes of the delays of linear time-varying Caputo fractional dynamic systems of real fractional order possessing internal point delays. The…

Dynamical Systems · Mathematics 2010-10-18 M. De La Sen

We consider continuous-time Markov chains on integers which allow transitions to adjacent states only, with alternating rates. We give explicit formulas for probability generating functions, and also for means, variances and state…

Probability · Mathematics 2019-10-30 Luisa Beghin , Claudio Macci , Barbara Martinucci

In this paper we study single-parametric systems of integer shifts of Gauss and Lorenz functions. In case of Cauchy--Lorenz system we explicitly calculate nod functions and prove that it tends to sinc function in limit. For both Gauss and…

Classical Analysis and ODEs · Mathematics 2014-08-19 E. A. Kiselev , L. A. Minin , I. Ya. Novikov , S. M. Sitnik

We study the long-time asymptotics of a certain class of nonlinear diffusion equations with time-dependent diffusion coefficients which arise, for instance, in the study of transport by randomly fluctuating velocity fields. Our primary goal…

Analysis of PDEs · Mathematics 2016-09-06 Gastão A. Braga , Frederico Furtado , Jussara M. Moreira , Leonardo T. Rolla

We derive an inequality relating the finite-frequency linear response and fluctuations of an observable in a physical system. The relation holds for arbitrary observables and perturbations in general Markovian dynamics, including over- and…

Statistical Mechanics · Physics 2025-10-20 Andreas Dechant

Integrals of motion and statistical properties of quantized electromagnetic field (e.-m. field) in time-dependent linear dielectric and conductive media are considered, using Choi-Yeon quantization, based on Caldirola-Kanai type…

Quantum Physics · Physics 2015-04-08 A. K. Angelow , D. A. Trifonov

In recent papers it has been demonstrated that sampling a Gibbs distribution from an appropriate time-irreversible Langevin process is, from several points of view, advantageous when compared to sampling from a time-reversible one. Adding…

Probability · Mathematics 2015-02-20 Luc Rey-Bellet , Konstantinos Spiliopoulos

In this paper the linear and stationary Discrete-time systems with state variables and dynamic coefficients represented by fuzzy numbers are studied, providing some stability criteria, and characterizing the bounds of the set of solutions…

Systems and Control · Computer Science 2011-09-05 Gabriele Oliva , Stefano Panzieri , Roberto Setola