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Related papers: The Kaczmarz Algorithm in Hilbert $C^{*}$-modules

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The Kaczmarz method for solving linear systems of equations is an iterative algorithm that has found many applications ranging from computer tomography to digital signal processing. Despite the popularity of this method, useful theoretical…

Numerical Analysis · Mathematics 2007-05-23 Thomas Strohmer , Roman Vershynin

The Kaczmarz method is successfully used for solving discretizations of linear inverse problems, especially in computed tomography where it is known as ART. Practitioners often observe and appreciate its fast convergence in the first few…

Numerical Analysis · Mathematics 2026-01-13 Per Christian Hansen , Michiel E. Hochstenbach

Analogues for Hilbert C*-modules of classical results of Fourier series theory in Hilbert spaces are considered. Relations between different properties of orthogonal and orthonormal systems for Hilbert C*-modules are studied with special…

Operator Algebras · Mathematics 2009-06-05 Giovanni Landi , Alexander Pavlov

This paper studies the problems of embedding and isomorphism for countably generated Hilbert C*-modules over commutative C*-algebras. When the fibre dimensions differ sufficiently, relative to the dimension of the spectrum, we show that…

Operator Algebras · Mathematics 2015-06-01 Leonel Robert , Aaron Tikuisis

Hilbert space fusion frames are a natural extension of Hilbert space frames, extending the notion from a set of vectors in a Hilbert space to a set of subspaces of a Hilbert space with analogous notions of overcompleteness and boundedness.…

Functional Analysis · Mathematics 2017-06-23 Mozhgan Mohammadpour , Brian Tuomanen , Rajab Ali Kamyabi Gol

The Randomized Kaczmarz Algorithm is a randomized method which aims at solving a consistent system of over determined linear equations. This note discusses how to find an optimized randomization scheme for this algorithm, which is related…

Systems and Control · Computer Science 2016-11-17 Liang Dai , Mojtaba Soltanalian , Kristiaan Pelckmans

The Kaczmarz algorithm (KA) is a popular method for solving a system of linear equations. In this note we derive a new exponential convergence result for the KA. The key allowing us to establish the new result is to rewrite the KA in such a…

Systems and Control · Computer Science 2015-06-23 Liang Dai , Thomas Schön

We define a categorical framework in which we build a systematic construction that provides generic invariants for C*-algebras. The benefit is significant as we show that any invariant arising this way automatically enjoys nice properties…

Operator Algebras · Mathematics 2023-09-06 Laurent Cantier

We present a Hilbert space approach to the limit joint *-distributions of complex independent Gaussian random matrices. For that purpose, we use a suitably defined family of creation and annihilation operators living in some direct integral…

Operator Algebras · Mathematics 2020-04-03 Romuald Lenczewski

We construct Hilbert $C^*$-modules useful for studying Gabor systems and show that they are Banach algebras under pointwise multiplication. For rational $ab<1$ we prove that the set of functions $g \in L^2(R)$ so that $(g,a,b)$ is a Bessel…

Functional Analysis · Mathematics 2007-05-23 Michael Coco , M. C. Lammers

The goal of the present paper is to extend the theory of frames for countably generated Hilbert $C^*$-modules over arbitrary $C^*$-algebras. In investigating the non-unital case we introduce the concept of outer frame as a sequence in the…

Operator Algebras · Mathematics 2015-07-16 Ljiljana Arambašić , Damir Bakić

We introduce a new iterative regularization method for solving inverse problems that can be written as systems of linear or non-linear equations in Hilbert spaces. The proposed averaged Kaczmarz (AVEK) method can be seen as a hybrid method…

Numerical Analysis · Mathematics 2018-03-09 Housen Li , Markus Haltmeier

The classical Kaczmarz iteration and its randomized variants are popular tools for fast inversion of linear overdetermined systems. This method extends naturally to the setting of the phase retrieval problem via substituting at each…

Numerical Analysis · Mathematics 2017-07-25 Halyun Jeong , C. Sinan Güntürk

The Kaczmarz algorithm is a popular solver for overdetermined linear systems due to its simplicity and speed. In this paper, we propose a modification that speeds up the convergence of the randomized Kaczmarz algorithm for systems of linear…

Numerical Analysis · Computer Science 2013-05-17 Hassan Mansour , Ozgur Yilmaz

In this paper, we introduce the notion of invariant submodule in the theory of Hilbert C*-modules and study some basic properties of bounded adjointable operators and their generalized inverses which have nontrivial invariant submodules. We…

Operator Algebras · Mathematics 2025-06-03 Kamran Sharifi

Kernel methods have been among the most popular techniques in machine learning, where learning tasks are solved using the property of reproducing kernel Hilbert space (RKHS). In this paper, we propose a novel data analysis framework with…

Machine Learning · Statistics 2021-12-22 Yuka Hashimoto , Isao Ishikawa , Masahiro Ikeda , Fuyuta Komura , Takeshi Katsura , Yoshinobu Kawahara

In this paper, we introduce controlled frames in Hilbert $C^*$-modules and we show that they share many useful properties with their corresponding notions in Hilbert space. Next, we give a characterization of controlled frames in Hilbert…

Operator Algebras · Mathematics 2017-05-02 Mehdi Rashidi-Kouchi , Asghar Rahimi

Stable computational algorithms for the approximate solution of the Cauchy problem for nonstationary problems are based on implicit time approximations. Computational costs for boundary value problems for systems of coupled multidimensional…

Numerical Analysis · Mathematics 2024-03-28 P. N. Vabishchevich

This paper presents a general coding method where data in a Hilbert space are represented by finite dimensional coding vectors. The method is based on empirical risk minimization within a certain class of linear operators, which map the set…

Machine Learning · Statistics 2011-09-05 Andreas Maurer Massimiliano Pontil

A $C^*$-textile dynamical system $({\cal A}, \rho,\eta,\Sigma^\rho,\Sigma^\eta, \kappa)$ connsists of a unital $C^*$-algebra ${\cal A}$, two families of endomorphisms ${\rho_\alpha}_{\alpha \in \Sigma^\rho}$ and ${\eta_a}_{a \in…

Operator Algebras · Mathematics 2011-11-15 Kengo Matsumoto