Results 11 to 20 of about 478,994 (322)
Subnormal composition operators [PDF]
Proceedings of the American Mathematical Society, 1988 Let C C be the composition operator on L 2 ( X , Σ , m ) {L^2}(X,\Sigma ,m) given by C f = f ∘ T Cf = f \circ T , where T T is a Σ
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A hyperbolic universal operator commuting with a compact operator [PDF]
, 2019 A Hilbert space operator is called universal (in the sense of Rota) if every operator on the Hilbert space is similar to a multiple of the restriction of the universal operator to one of its invariant subspaces.
Cowen, Carl C. +1 more
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Completely Continuous Composition Operators [PDF]
Transactions of the American Mathematical Society, 1994 Summary: A composition operator \(T_ b f= f\circ b\) is completely continuous on \(H^ 1\) if and only if \(| b|< 1\) a.e. If the adjoint operator \(T^*_ b\) is completely continuous on VMOA, then \(T_ b\) is completely continuous on \(H^ 1\). Examples are given to show that the converse fails in general.
Cima, Joseph A., Matheson, Alec
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The Numerical Range of C*ψ Cφ and Cφ C*ψ
Concrete Operators, 2021 In this paper we investigate the numerical range of C*bφm Caφn and Caφn C*bφm on the Hardy space where φ is an inner function fixing the origin and a and b are points in the open unit disc.
Clifford John +2 more
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A Novel Reliability Analysis Method for Fuzzy Multi-State Systems Considering Correlation
IEEE Access, 2019 Fuzzy multi-state systems (FMSSs) exist widely in practical engineering. It is usually difficult to evaluate the reliability of FMSSs because the reliability data is usually fuzzy due to the inaccuracy or imperfection of information, and there is often ...
Huiying Gao, Xiaoqiang Zhang
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Composition and Inversion of Schema Mappings [PDF]
, 2010 In the recent years, a lot of attention has been paid to the development of solid foundations for the composition and inversion of schema mappings. In this paper, we review the proposals for the semantics of these crucial operators.
Arenas, Marcelo +3 more
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Fredholm composition operators [PDF]
Proceedings of the American Mathematical Society, 1980 In this paper a necessary and sufficient condition for a composition operator C T {C_T} on L 2 [ 0 , 1 ] {L^2}[0,1] to be a Fredholm operator is given.
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Composition Operators and Endomorphisms [PDF]
Complex Analysis and Operator Theory, 2010 If $b$ is an inner function, then composition with $b$ induces an endomorphism, $ $, of $L^\infty(\mathbb{T})$ that leaves $H^\infty(\mathbb{T})$ invariant. We investigate the structure of the endomorphisms of $B(L^2(\mathbb{T}))$ and $B(H^2(\mathbb{T}))$ that implement $ $ through the representations of $L^\infty(\mathbb{T})$ and $H^\infty(\mathbb{T}
Courtney, Dennis +2 more
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Demonstratio Mathematica, 2014 In this paper, we consider the Nemytskii operator (Hf)(t) = h(t, f(t)), generated by a given function h. It is shown that if H is globally Lipschitzian and maps the space of functions of bounded (p,2,α)-variation (with respect to a weight function α ...
Aziz Wadie
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An approach to elliptic equations with nonlinear gradient terms via a modulation framework
Bulletin of Mathematical Sciences, 2023 We consider a class of nonhomogeneous elliptic equations with fractional Laplacian and nonlinear gradient terms, namely [Formula: see text] in [Formula: see text], where [Formula: see text], [Formula: see text] is the nonlinearity, [Formula: see text ...
Lucas C. F. Ferreira, Wender S. Lagoin
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