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In \cite{AP2} we obtained general estimates of the operator moduli of continuity of functions on the real line. In this paper we improve the estimates obtained in \cite{AP2} for certain special classes of functions. In particular, we…

Functional Analysis · Mathematics 2011-04-19 Aleksei Aleksandrov , Vladimir Peller

Centered weighted composition operators on $L^2$-spaces are characterized. The characterization is obtained without the assumption that the operator is a product of a multiplication and a composition operator. The concept of spectrally…

Functional Analysis · Mathematics 2026-04-20 Piotr Budzyński

The aim of this article is to establish the $L^p(\mathbb{R}^2)$-boundedness of the variational operator associated with averaging operators defined over finite type curves in the plane. Additionally, we present the necessary conditions for…

Classical Analysis and ODEs · Mathematics 2025-01-29 Xudong Nie

We establish H\"ormander-type $L^2$-estimates for the $\overline{\partial}$-operators that hold uniformly for all nontrivial flat holomorphic line bundles on compact K\"ahler manifolds. Our result can be regarded as a…

Complex Variables · Mathematics 2023-04-04 Yoshinori Hashimoto , Takayuki Koike

Arag\'on Artacho and Campoy recently proposed a new method for computing the projection onto the intersection of two closed convex sets in Hilbert space; moreover, they proposed in 2018 a generalization from normal cone operators to…

Optimization and Control · Mathematics 2018-05-30 Salihah Alwadani , Heinz H. Bauschke , Walaa M. Moursi , X. Wang

By considering generalized logarithm and exponential functions used in nonextensive statistics, the four usual algebraic operators : addition, subtraction, product and division, are generalized. The properties of the generalized operators…

Mathematical Physics · Physics 2009-11-10 L. Nivanen , A. Le Mehaute , Q. A. Wang

Maximally monotone operators are fundamental objects in modern optimization. The main classes of monotone operators are subdifferential operators and matrices with a positive semidefinite symmetric part. In this paper, we study a nice class…

Functional Analysis · Mathematics 2021-03-25 Salihah Alwadani , Heinz H. Bauschke , Julian P. Revalski , Xianfu Wang

The notion of a firmly nonexpansive mapping is central in fixed point theory because of attractive convergence properties for iterates and the correspondence with maximal monotone operators due to Minty. In this paper, we systematically…

Functional Analysis · Mathematics 2011-01-26 Heinz H. Bauschke , Sarah M. Moffat , Xianfu Wang

In this paper we consider a generalized version of bounded oscillation operators, involving new parameters in the definition, as well as considering the operators on vector-valued function spaces. With this definition we will capture some…

Classical Analysis and ODEs · Mathematics 2023-08-08 Grigori A. Karagulyan

We realize norms of most composition operators acting on the Hardy space with linear fractional symbol as roots of hypergeometric functions. This realization leads to simple necessary and sufficient conditions on the symbol to exhibit…

Complex Variables · Mathematics 2007-05-23 Estelle L. Basor , Dylan Q. Retsek

In the paper, we investigate weighted composition operators on Bergman spaces of a half-plane. We characterize weighted composition operators which are hermitian and those which are complex symmetric with respect to a family of…

Functional Analysis · Mathematics 2021-11-30 Pham Viet Hai , Osmar R. Severiano

We obtain some results about the spectrum and the upper semi-Fredholm spectrum of weighted composition operators on uniform algebras, assuming that the corresponding map maps the Shilov boundary onto itself. In particular, it follows from…

Spectral Theory · Mathematics 2024-01-31 Arkady Kitover , Mehmet Orhon

Using an integral formula on a homogeneous Siegel domain, we show a necessary and sufficient condition for composition operators on the weighted Bergman space of a minimal bounded homogeneous domain to be compact. To describe the…

Functional Analysis · Mathematics 2011-05-10 Satoshi Yamaji

This paper provides a class of complex symmetric weighted composition operators on $H^2(\mathbb{D})$ to includes the unitary subclass, the Hermitian subclass and the normal subclass obtained by Bourdon and Noor. A characterization of…

Functional Analysis · Mathematics 2018-12-27 Cao Jiang , Shi-An Han , Ze-Hua Zhou

We introduce the class of $\alpha$-firmly nonexpansive and quasi $\alpha$-firmly nonexpansive operators on $r$-uniformly convex Banach spaces. This extends the existing notion from Hilbert spaces, where $\alpha$-firmly nonexpansive…

Functional Analysis · Mathematics 2025-03-11 Arian Bërdëllima , Gabriele Steidl

We show that the set of fixed points of the average of two resolvents can be found from the set of fixed points for compositions of two resolvents associated with scaled monotone operators. Recently, the proximal average has attracted…

Functional Analysis · Mathematics 2010-03-26 Xianfu Wang , Heinz H. Bauschke

We develop the method of averaging in Clifford (geometric) algebras suggested by the author in previous papers. We consider operators constructed using two different sets of anticommuting elements of real or complexified Clifford algebras.…

Mathematical Physics · Physics 2023-08-24 D. S. Shirokov

This article studies optional and predictable projections of integrands and convex-valued stochastic processes. The existence and uniqueness are shown under general conditions that are analogous to those for conditional expectations of…

Probability · Mathematics 2016-07-25 Matti Kiiski , Ari-Pekka Perkkiö

Bisimulation metric is a robust behavioural semantics for probabilistic processes. Given any SOS specification of probabilistic processes, we provide a method to compute for each operator of the language its respective metric…

Programming Languages · Computer Science 2014-08-08 Daniel Gebler , Simone Tini

It is known that the weighted $L^2$ projection operator exhibits approximation properties different from those of the classical $L^2$ projection, in the sense that the $L^2$ error of the weighted $L^2$ projection of an $H^1$ function…

Numerical Analysis · Mathematics 2026-05-08 Qiya Hu , Yuhan Luo