Results 31 to 40 of about 714 (196)

Modular Riesz bases versus Riesz bases in Hilbert C∗-modules [PDF]

Asian-European Journal of Mathematics, 2019
In this paper, we give new characterizations of modular Riesz bases in Hilbert [Formula: see text]-modules. We prove that modular Riesz bases share many properties with Riesz bases in Hilbert spaces. Moreover, we show that there are also important differences; for example, there exist exact frames that are not modular Riesz bases.
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On the Stability of Frames and Riesz Bases

Applied and Computational Harmonic Analysis, 1995
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Favier, S.J., Zalik, R.A.
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Riesz Basicity for General Systems of Functions

Journal of Function Spaces, 2014
In this paper we find the general conditions for a complete biorthogonal conjugate system to form a Riesz basis. We show that if a complete biorthogonal conjugate system is uniformly bounded and its coefficient space is solid, then the system forms a ...
A. M. Sarsenbi, P. A. Terekhin
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Some New Notions of Bases for the Range of Operators in Hilbert Spaces [PDF]

Sahand Communications in Mathematical Analysis
This paper is devoted to introduce a new concept of bases for the range of the operator $K$. Actually, we consider controlled $K$-orthonormal and controlled $K$-Riesz bases which are a generalization of ordinary bases in Hilbert spaces. In the sequel, we
Hessam Hosseinnezhad
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Continuous-Domain Formulation of Inverse Problems for Composite Sparse-Plus-Smooth Signals

IEEE Open Journal of Signal Processing, 2021
We present a novel framework for the reconstruction of 1D composite signals assumed to be a mixture of two additive components, one sparse and the other smooth, given a finite number of linear measurements.
Thomas Debarre, Shayan Aziznejad, Michael Unser   +2 more
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$G$-dual Frames in Hilbert $C^{*}$-module Spaces [PDF]

Sahand Communications in Mathematical Analysis, 2018
In this paper, we introduce the concept of $g$-dual frames for Hilbert $C^{*}$-modules, and then the properties and stability results of $g$-dual frames  are given.
Fatemeh Ghobadzadeh, Abbas Najati
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Inverse Problem for a Fourth-Order Hyperbolic Equation with a Complex-Valued Coefficient

Mathematics, 2023
This paper studies the existence and uniqueness of the classical solution of inverse problems for a fourth-order hyperbolic equation with a complex-valued coefficient with Dirichlet and Neumann boundary conditions.
Asselkhan Imanbetova, Abdissalam Sarsenbi, Bolat Seilbekov   +2 more
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RIESZ MULTIWAVELET BASES [PDF]

, 2008
. Compactly supported Riesz wavelets are of interest in several applications such as image processing, computer graphics and numerical algorithms. In this paper, we shall investigate compactly supported MRA Riesz multiwavelet bases in L2(R). An algorithm

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A note on exponential Riesz bases

Sampling Theory, Signal Processing, and Data Analysis, 2022
AbstractWe prove that if$$I_\ell = [a_\ell ,b_\ell )$$Iℓ=[aℓ,bℓ),$$\ell =1,\ldots ,L$$ℓ=1,…,L, are disjoint intervals in [0, 1) with the property that the numbers$$1, a_1, \ldots , a_L, b_1, \ldots , b_L$$1,a1,…,aL,b1,…,bLare linearly independent over$${\mathbb {Q}}$$Q, then there exist pairwise disjoint sets$$\Lambda _\ell \subset {\mathbb {Z}}$$Λℓ⊂Z,$
Andrei Caragea, Dae Gwan Lee
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Approximate Duals of $g$-frames and Fusion Frames in Hilbert $C^ast-$modules [PDF]

Sahand Communications in Mathematical Analysis, 2019
In this paper, we study approximate duals of $g$-frames and fusion frames in Hilbert $C^ast-$modules. We get some relations between approximate duals of $g$-frames and biorthogonal Bessel sequences, and using these relations, some results for approximate
Morteza Mirzaee Azandaryani
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