Results 21 to 30 of about 1,105 (155)
Kodai Mathematical Journal, 1990 For every point a in the unit disc U, \(\psi_ a(z)=(z+a)/(1+\bar az)\) denotes the conformal map of U onto itself with \(\psi_ a(0)=a\). For a function f analytic in U, we set \(f_ a(z)=f(\psi_ a(z))-f(a)\), and the BMO norm \(B_ p(f)\) of f is defined by \(B_ p(f)=\sup \{\| f_ a\|_ p:\) \(a\in U\}\), where \(\| \cdot \|_ p\) denotes the ordinary Hardy
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Compact Composition Operators on BMOA [PDF]
Transactions of the American Mathematical Society, 1999 We characterize the compact composition operators on BMOA, the space consisting of those holomorphic functions on the open unit disk U U that are Poisson integrals of functions on ∂ U \partial U , that have bounded mean oscillation.
Bourdon, P. S. +2 more
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A family of Dirichlet-Morrey spaces [PDF]
, 2018 To each weighted Dirichlet space $\mathcal{D}_p ...
Galanopoulos, Petros +2 more
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A Hankel matrix acting on spaces of analytic functions [PDF]
, 2017 If $\mu $ is a positive Borel measure on the interval $[0, 1)$ we let $\mathcal H_\mu $ be the Hankel matrix $\mathcal H_\mu =(\mu _{n, k})_{n,k\ge 0}$ with entries $\mu _{n, k}=\mu _{n+k}$, where, for $n\,=\,0, 1, 2, \dots $, $\mu_n$ denotes the moment ...
Girela, Daniel, Merchán, Noel
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Some unsolved problems on meromorphic functions of uniformly bounded characteristic
International Journal of Mathematics and Mathematical Sciences, 1985 The family UBC(R) of meromorphic functions of uniformly bounded characteristic in a Rieman surface R is defined in terms of the Shimizu-Ahlfors characteristic function.
Shinji Yamashita
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Weighted Composition Operators on BMOA [PDF]
Computational Methods and Function Theory, 2008 The author completely characterizes the boundedness and compactness of the weighted composition operator \(W_{\psi,\varphi}f=\psi (f\circ \varphi)\) acting on \(BMOA\) and \(VMOA\) of the unit disc. The results extend and unify those known for the cases \(\varphi(z)=z\) and \(\psi(z)=1\) corresponding to the multiplication operator \(M_\psi\) [see ...
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Vectorial Hankel operators, Carleson embeddings, and notions of $BMOA$ [PDF]
, 2017 We consider operators of the type $D^\alpha:H^2(\mathcal{H})\to H^2(\mathcal{H})$, where $D^\alpha$ denotes a fractional differentiation operator, and $\Gamma_\phi$ is a Hankel operator.
Rydhe, Eskil
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An Adaptive Particle Swarm Optimization Algorithm for Unconstrained Optimization
Complexity, Volume 2020, Issue 1, 2020., 2020 Conventional optimization methods are not efficient enough to solve many of the naturally complicated optimization problems. Thus, inspired by nature, metaheuristic algorithms can be utilized as a new kind of problem solvers in solution to these types of optimization problems.
Feng Qian +5 more
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BMOA Characterization with Families of Cauchy Transforms
Sultan Qaboos University Journal for Science, 1999 In this paper we prove a number of results on Cauchy transforms of generalized type given by Borel measures supported on the class of analytic functions mapping the unit disc into the unit desk.
Yusuf Abu Muhanna, El-Bachir Yallaoui
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The Weiss conjecture on admissibility of observation operators for contraction semigroups [PDF]
, 2001 We prove the conjecture of George Weiss for contraction semigroups on Hilbert spaces, giving a characterization of infinite-time admissible observation functionals for a contraction semigroup, namely that such a functional C is infinite-time admissible ...
A. Simard +13 more
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