Results 161 to 170 of about 2,927,156 (202)

Hyponormal Composition Operators

Bulletin of the London Mathematical Society, 1986
Let (X,\(\Sigma\),m) be a complete \(\sigma\)-finite measure space, and let T be a \(\Sigma\)-measurable mapping in X such that \(m\circ T^{-1}\) is absolutely continuous with respect to m. The corresponding weighted composition operator W on \(L^ 2(X,\Sigma,m)\) generated by the weight function \(\phi\) is defined by \(Wf:=\phi f\circ T\).
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Operations and compositions in transrecursive operators

Cybernetics and Systems Analysis, 1994
Earlier, the authors introduced classes of alphabetic operators that have greater computational possibilities than classical algorithms. In Dokl. Akad. Nauk SSSR 321, No. 5, 876-879 (1991), they gave a uniform procedure for obtaining such alphabetic operators, which will be called transrecursive operators in what follows.
Burgin, M. S., Borodyanskij, Yu. M.
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Implementations of program composition operations

1994
This paper reports on a number of implementations for a suite of composition operations of logic programs. We present and compare three implementations, which rely on different techniques: metaprogramming, program transformations, and extensions to the WAM, respectively.
Brogi A, Chiarelli A, Mancarella P, Mazzotta V, Pedreschi D, Renso C, Turini, F   +7 more
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Considerations on Compositional Update Operators

2000
We develop two specific operators for modifying a knowledge base: Amend updates a knowledge base with a formula, while the complementary operator Forget removes a formula from the knowledge base. The approach differs from other belief change operators in that the definition of the operators is compositional with respect to the sentence added or removed.
James P. Delgrande, Matthew Suderman
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Eigenvalues of Adjoints of Certain Composition Operators and Weighted Composition Operators

Integral Equations and Operator Theory, 2014
The paper is concerned with the spectral theory of composition operators on the Hardy space \(H^2\) of the unit disk. The author proves that, under certain conditions on the symbol \(\varphi \) (involving in particular fixed points), the point-spectrum of the adjoint \(C_\varphi^*\) of \(C_\varphi\) contains a disk centered at the origin.
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Commutators of composition operators with adjoints of composition operators on the ball

Complex Variables and Elliptic Equations, 2015
In this paper, we investigate compactness of the commutator on the Hardy space or the weighted Bergman space (), when and are automorphisms of the unit ball . We obtain that is compact if and only if both and are unitary and they commute. This generalizes the corresponding result in one variable. Moreover, our technique is different and simple.
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A model for composable composition operators

Proceedings of the 9th International Conference on Aspect-Oriented Software Development, 2010
A considerable amount of research, especially within the OO and AOSD communities, has focused on understanding the potential and limitations of various composition techniques. This has led to a large amount of proposals for alternative composition techniques, including many variations of message dispatch, inheritance, and aspect mechanisms.
Havinga, Wilke, Bergmans, Lodewijk, Akşit, Mehmet   +2 more
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Composition operators on potential spaces

Proceedings of the American Mathematical Society, 1992
By a result of B. Dahlberg, the composition operators T H
Adams, David R., Frazier, Michael
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Operator regularization and composite operators

Canadian Journal of Physics, 1990
We demonstrate how operator regularization can be used to compute radiative corrections to Green's functions involving composite operators. No divergences are encountered and no symmetry-breaking regulating parameter need be introduced into the initial Lagrangian.
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Composition operators on f-algebras

Positivity, 2016
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Abid, R., Ben Amor, Mohamed Amine, Boulabiar, Karim   +2 more
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