Search results for "Operator"

showing 10 items of 1427 documents

(H,ρ)-induced dynamics and large time behaviors

2018

In some recent papers, the so called (H,ρ)-induced dynamics of a system S whose time evolution is deduced adopting an operatorial approach, borrowed in part from quantum mechanics, has been introduced. Here, H is the Hamiltonian for S, while ρ is a certain rule applied periodically (or not) on S. The analysis carried on throughout this paper shows that, replacing the Heisenberg dynamics with the (H,ρ)-induced one, we obtain a simple, and somehow natural, way to prove that some relevant dynamical variables of S may converge, for large t, to certain asymptotic values. This cannot be so, for finite dimensional systems, if no rule is considered. In this case, in fact, any Heisenberg dynamics im…

(Hρ)-induced dynamicOperatorial modelSchrödinger and Heisenberg dynamicStressed bacterial population(Hρ)-induced dynamics; Operatorial models; Schrödinger and Heisenberg dynamics; Stressed bacterial populations; Statistics and Probability; Condensed Matter PhysicsSettore MAT/07 - Fisica Matematica
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Dual attachment pairs in categorically-algebraic topology

2011

[EN] The paper is a continuation of our study on developing a new approach to (lattice-valued) topological structures, which relies on category theory and universal algebra, and which is called categorically-algebraic (catalg) topology. The new framework is used to build a topological setting, based in a catalg extension of the set-theoretic membership relation "e" called dual attachment, thereby dualizing the notion of attachment introduced by the authors earlier. Following the recent interest of the fuzzy community in topological systems of S. Vickers, we clarify completely relationships between these structures and (dual) attachment, showing that unlike the former, the latter have no inh…

(pre)image operatorWeak topologyTopological algebralcsh:Mathematicslcsh:QA299.6-433Quasi-framelcsh:AnalysisTopological spacelcsh:QA1-939Topological vector spaceHomeomorphismAlgebraDual attachment pair(LM)-fuzzy topologyTrivial topologyCategory of topological spacesVarietyGeometry and TopologyGeneral topology(lattice-valued) categorically-algebraic topologyTopological systemQuasi-coincidence relationSpatialization(localic) algebraMathematics
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Two-dimensional Banach spaces with polynomial numerical index zero

2009

We study two-dimensional Banach spaces with polynomial numerical indices equal to zero.

/dk/atira/pure/subjectarea/asjc/2600/2608/dk/atira/pure/subjectarea/asjc/2600/2607Eberlein–Šmulian theoremBanach manifoldFinite-rank operatorPolynomialMatrix polynomialFOS: MathematicsDiscrete Mathematics and Combinatorics/dk/atira/pure/subjectarea/asjc/2600/2602C0-semigroupLp spaceMathematicsMathematics::Functional AnalysisNumerical AnalysisBanach spaceAlgebra and Number TheoryMathematical analysisFunctional Analysis (math.FA)Mathematics - Functional Analysis46B04 (Primary) 46B20 46G25 47A12 (Secondary)Polynomial numerical indexInterpolation space/dk/atira/pure/subjectarea/asjc/2600/2612Geometry and TopologyNumerical rangeMonic polynomialLinear Algebra and its Applications
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A singular (p,q)-equation with convection and a locally defined perturbation

2021

Abstract We consider a parametric Dirichlet problem driven by the ( p , q ) -Laplacian and a reaction which is gradient dependent (convection) and the competing effects of two more terms, one a parametric singular term and a locally defined perturbation. We show that for all small values of the parameter the problem has a positive smooth solution.

010101 applied mathematicsDirichlet problemConvectionApplied Mathematics010102 general mathematicsMathematical analysisSingular termPerturbation (astronomy)0101 mathematics01 natural sciencesLaplace operatorMathematicsParametric statisticsApplied Mathematics Letters
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q–analogue of generalized Ruschweyh operator related to a new subfamily of multivalent functions

2019

Abstract A new subfamily of p–valent analytic functions with negative coefficients in terms of q–analogue of generalized Ruschweyh operator is considered. Several properties concerning coefficient bounds, weighted and arithmetic mean, radii of starlikeness, convexity and close-to-convexity are obtained. A family of class preserving integral operators and integral representation are also indicated.

010101 applied mathematicsPure mathematicsSubfamilyOperator (physics)010102 general mathematics0101 mathematics01 natural sciencesMathematicsGeneral Mathematics
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Voronovskaya type results and operators fixing two functions

2021

The present paper deals with positive linear operators which fix two functions. The transfer of a given sequence (Ln) of positive linear operators to a new sequence (Kn) is investigated. A general procedure to construct sequences of positive linear operators fixing two functions which form an Extended Complete Chebyshev system is described. The Voronovskaya type formula corresponding to the new sequence which is strongly influenced by the nature of the fixed functions is obtained. In the last section our results are compared with other results existing in literature.

010101 applied mathematicsextended complete Chebyshev systemModeling and Simulation010102 general mathematicsQA1-939operators fixing two functionsVoronovskaya type theorem0101 mathematics01 natural sciencesAnalysisMathematicspositive linear operatorsMathematical Modelling and Analysis
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Critical issues in the PD testing methodology for XLPE-insulated MV cables: An experimental case

2017

This paper describes some critical issues arising during the partial discharge (PD) testing of a 500m delivery length of an XLPE-insulated MV cable. At first, conventional PD measurements were performed on the whole length by using a standard acquisition system; PDs activity was detected, but the system allowed the operator to localize the PDs only on a length of 70 m. A visual inspection of this section highlighted the presence of an excoriation in the outer sheet. Aiming at a more accurate pin-pointing of the defect, more measurements were carried out in the proximity of the outer defect using a portable PD detection system. These measurements showed PDs activity, whose source was located…

010302 applied physicsOperator (computer programming)Cables Cable testing MV cables Partial Discharges Partial Discharge Measurements Partial Discharge testing PD detection Wireless PD detection XLPE-insulated cablesSection (archaeology)Computer scienceAcoustics0103 physical sciencesExcoriationPartial discharge01 natural sciences2017 IEEE Conference on Electrical Insulation and Dielectric Phenomenon (CEIDP)
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Calculation of electronic g-tensors using coupled cluster theory.

2009

A scheme for the calculation of the electronic g-tensor at the coupled cluster (CC) level is presented. The reported implementation employs an effective one-electron spin-orbit operator, allows the inclusion of arbitrary excitations in the cluster operator, and offers various options concerning the treatment of orbital relaxation and choice of reference determinants. In addition, the use of gauge-including atomic orbitals (GIAOs) is possible to overcome the gauge origin problem. Benchmark calculations for the NH ((3)Sigma(-)) radical reveal the importance of electron correlation effects for the accurate prediction of the g-shift as well as the slow basis set convergence of such calculations…

010304 chemical physicsElectronic correlationChemistryOperator (physics)010402 general chemistry01 natural sciences0104 chemical sciencesHybrid functionalCoupled clusterAtomic orbitalQuantum mechanics0103 physical sciencesCluster (physics)Density functional theoryPhysical and Theoretical ChemistryBasis setThe journal of physical chemistry. A
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A Global Sensitivity Analysis Toolbox to Quantify Drivers of Vegetation Radiative Transfer Models

2017

Abstract Global sensitivity analysis (GSA) enables to gain insight into the functioning of radiative transfer models (RTMs) by identifying the driving input variables of RTM spectral outputs such as reflectance, fluorescence, or radiance. This contribution introduces automated radiative transfer models operator's (ARTMO’s) new GSA toolbox. With the GSA toolbox the majority of ARTMO’s available RTMs can be decomposed into its driving variables. For a selected RTM output, a GSA identifies the most influential and noninfluential input variables according to Sobol' first-order and total-order indices. The toolbox can process RTM spectral outputs for any kind of optical sensor setting within the…

010504 meteorology & atmospheric sciences0211 other engineering and technologiesProcess (computing)Sobol sequence02 engineering and technology01 natural sciencesToolboxOperator (computer programming)GeographyRadiative transferRadianceRange (statistics)Sensitivity (control systems)021101 geological & geomatics engineering0105 earth and related environmental sciencesRemote sensing
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Flow measurement using circular portable flume

2018

Abstract The circular portable flume is a simple device to measure discharge in circular drainage networks. Since the unit can be easily installed and removed, it is helpful in water distribution measurement and management. First in this paper the available studies are reviewed for highlighting the effect of both the contraction ratio and the flume slope on the stage-discharge relationship. Then the Buckingham's Theorem of the dimensional analysis and the self-similarity theory are used to deduce the stage-discharge curve of the circular flume. The new theoretical stage-discharge equation is calibrated by the literature available experimental data and those obtained in this experimental inv…

0208 environmental biotechnology02 engineering and technology01 natural sciencesMeasure (mathematics)Flow measurement010309 optics0103 physical sciencesRange (statistics)Portable flumeStage-discharge curveSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliElectrical and Electronic EngineeringBuckingham's theoremContraction (operator theory)Contraction ratioInstrumentationDrainage networkExperimental dataComputer Science Applications1707 Computer Vision and Pattern RecognitionMechanics020801 environmental engineeringComputer Science ApplicationsFlumeFlow measurementDistribution (mathematics)Circular flumeModeling and SimulationGeology
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