Results 31 to 40 of about 104,503 (165)
On a compound approximation operator of D.D. Stancu type
Journal of Numerical Analysis and Approximation Theory, 2006 In this note we consider a linear and positive compound approximation operator of D.D. Stancu type depending of several parameters; we give the expressions of this operator on the test functions, the conditions under which this operator converges to a ...
Maria Crăciun
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Spectral decomposition of self-adjoint operators in Pontryagin and Krein spaces
Современная математика: Фундаментальные направленияWe consider a self-adjoint operator acting in a Krein space and possessing an invariant subspace that is maximal nonnegative and decomposes into a direct sum of a uniformly positive (i.e., equivalent to a Hilbert space with respect to the inner ...
V. A. Strauss
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Agrobacterium tumefaciens estC, Encoding an Enzyme Containing Esterase Activity, Is Regulated by EstR, a Regulator in the MarR Family. [PDF]
PLoS ONE, 2016 Analysis of the A. tumefaciens genome revealed estC, which encodes an esterase located next to its transcriptional regulator estR, a regulator of esterase in the MarR family.
Surawach Rittiroongrad +4 more
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Boundedly solvable extensions of delay differential operators
Electronic Journal of Differential Equations, 2017 We describe all boundedly solvable extensions of minimal operators generated by first-order linear delay differential operators in Hilbert spaces of vector-functions on finite intervals. Also, we study the structure of spectrum of these extensions.
Bahadir O. Guler +2 more
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Exponential Formulas and Lie Algebra Type Star Products
Symmetry, Integrability and Geometry: Methods and Applications, 2012 Given formal differential operators $F_i$ on polynomial algebrain several variables $x_1,...,x_n$, we discuss finding expressions $K_l$ determined by the equation $exp(sum_i x_i F_i)(exp(sum_j q_j x_j)) = exp(sum_l K_l x_l)$ and their applications.
Dragutin Svrtan +5 more
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Solvability of multipoint differential operators of first order
Electronic Journal of Differential Equations, 2015 Based on methods of operator theory, we describe all boundedly solvable extensions of the minimal operator generated by a linear multipoint functional differential-operator expression of first order, in a direct sum of Hilbert space of vector ...
Zameddin I. Ismailov, Pembe Ipek
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Accretive and nonnegative perturbations of an abstract analogy for the operator of the third boundary problem and corresponding variational problems(in Ukrainian) [PDF]
Математичні Студії, 2011 In the paper the role of initial object is played by the positively definite operator L_0 acting in a Hilbert space H. The main object of the investigation is operator L B: It is interpreted as a perturbation of some proper extension of L0. Using methods
H. M. Kachurivska, O. G. Storozh
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Expressive Power and Intensional Operators
Journal of Logic, Language and InformationAbstractIn Entities and Indices, M. J. Cresswell argued that a first-order modal language can reach the expressive power of natural-language modal discourse only if we give to the formal language a semantics with indices containing infinite possible worlds and we add to it an infinite collection of operators $${{\varvec{actually}}}_n$$
Pablo Cubides Kovacsics, David Rey
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Operational semantics: Concepts and their expression [PDF]
Information Processing Letters, 2003 One of the earliest approaches to giving formal semantics for programming languages was ``operational semantics''. Enthusiasm for this approach has waxed and waned. The main objective of this paper is to tease apart some concepts involved in writing such operational descriptions and (as separately as possible) to discuss useful notations.
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Operator bases, S-matrices, and their partition functions
Journal of High Energy Physics, 2017 Relativistic quantum systems that admit scattering experiments are quantitatively described by effective field theories, where S-matrix kinematics and symmetry considerations are encoded in the operator spectrum of the EFT.
Brian Henning +3 more
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