Search results for "operators"

showing 10 items of 228 documents

CQ *-algebras of measurable operators

2022

Abstract We study, from a quite general point of view, a CQ*-algebra (X, 𝖀0) possessing a sufficient family of bounded positive tracial sesquilinear forms. Non-commutative L 2-spaces are shown to constitute examples of a class of CQ*-algebras and any abstract CQ*-algebra (X, 𝖀0) possessing a sufficient family of bounded positive tracial sesquilinear forms can be represented as a direct sum of non-commutative L 2-spaces.

Numerical AnalysisControl and OptimizationBanach C*-modules Non commutative integration Partial algebras of operators.Settore MAT/05 - Analisi MatematicaApplied MathematicsAnalysisMoroccan Journal of Pure and Applied Analysis
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Step-by-step integration for fractional operators

2018

Abstract In this paper, an approach based on the definition of the Riemann–Liouville fractional operators is proposed in order to provide a different discretisation technique as alternative to the Grunwald–Letnikov operators. The proposed Riemann–Liouville discretisation consists of performing step-by-step integration based upon the discretisation of the function f(t). It has been shown that, as f(t) is discretised as stepwise or piecewise function, the Riemann–Liouville fractional integral and derivative are governing by operators very similar to the Grunwald–Letnikov operators. In order to show the accuracy and capabilities of the proposed Riemann–Liouville discretisation technique and th…

Numerical AnalysisDiscretizationApplied Mathematics02 engineering and technologyFunction (mathematics)DerivativeWhite noise01 natural sciences010305 fluids & plasmasExponential functionFractional calculus020303 mechanical engineering & transports0203 mechanical engineeringModeling and SimulationStep function0103 physical sciencesPiecewiseApplied mathematicsFractional Calculus Riemman–Liouville Grünwald–Letnikov Discrete fractional operatorsMathematics
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Entanglement dynamics and relaxation in a few-qubit system interacting with random collisions

2008

The dynamics of a single qubit interacting by a sequence of pairwise collisions with an environment consisting of just two more qubits is analyzed. Each collision is modeled in terms of a random unitary operator with a uniform probability distribution described by the uniform Haar measure. We show that the purity of the system qubit as well as the bipartite and the tripartite entanglement reach time averaged equilibrium values characterized by large instantaneous fluctuations.These equilibrium values are independent of the order of collision among the qubits. The relaxation to equilibrium is analyzed also in terms of an ensemble average of random collision histories. Such average allows for…

OPERATORSPhysicsENSEMBLESQuantum PhysicsSequenceRANDOM UNITARY MATRICESFOS: Physical sciencesGeneral Physics and AstronomyQuantum PhysicsQuantum entanglementCollisionQUANTUM STATESquantum informationQubitBipartite graphRelaxation (physics)Unitary operatorStatistical physicsQuantum Physics (quant-ph)entanglementHaar measureEPL (Europhysics Letters)
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MR3667002 Reviewed Vogt, Dietmar(D-BUW) Hadamard operators on D′(Ω). (English summary) Math. Nachr. 290 (2017), no. 8-9, 1374–1380. 46F10 (46F12 47B3…

2017

In this paper, the Hadamard operators, i.e. a particular class of continuous linear operators on D′(Ω) whose set of eigenvectors is the class of monomials, are considered on an open set Ω⊂Rd. Specifically, Hadamard operators L are characterized by the multiplicative convolution, that is, there exists a distribution T such that L(S)=S⋆T, where the multiplicative convolution ⋆ is defined by (S⋆T)ϕ=Sy(Txϕ(xy)). To obtain this characterization, the author defines a particular extension to D(Ω˜), where Ω˜:=⋃a∈RdaΩ, of the transpose of Hadamard operators. This result is a generalization of a previous work of the author where only the case Ω=Rd was considered.

Operators on distributions and on test functions monomials as eigenvectors spaces of distributionsSettore MAT/05 - Analisi Matematica
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Direktīvas 2004/35/EK ieviešanas problēmas Latvijā: fizisko personu un operatora atbildības praktiskie aspekti un būtiskuma slieksnis

2019

Ņemot vērā vides atbildības korektas piemērošanas nozīmi mūsdienu situācijā, darba mērķis ir izvērtēt Direktīvas 2004/35/EK ieviešanas problemātiku Latvijā saistībā ar atbildības subjektu un būtiskuma slieksni. Tādējādi darba uzdevums ir sākotnēji izpētīt Direktīvas 2004/35/EK izpratni Latvijas tiesību sistēmā, analizējot tās materiāltiesisko, personu un laika tvēruma robežas. Tālākajā darba gaitā tiek aplūkoti ar direktīvu ieviestie jauninājumi Latvijas vides tiesību jomā salīdzinājumā ar iepriekš pastāvošo regulējumu. Darba praktiskajā daļā tiek turpmāk izvērsta operatora tiesiskā regulējuma attiecināšana uz fizisku personu, kā arī būtiskuma sliekšņa problemātika. Secināms, ka Latvija dir…

OperatorsBūtiskuma slieksnisDirektīva 2004/35/EKAtbildība par videi nodarīto kaitējumuJuridiskā zinātneFiziska persona kas neveic profesionālu darbību
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Spectral properties of random non-self-adjoint operators

2015

In this thesis we are interested in the spectral properties of random non-self-adjoint operators. Weare going to consider primarily the case of small random perturbations of the following two types of operators: 1. a class of non-self-adjoint h-differential operators Ph, introduced by M. Hager [32], in the semiclassical limit (h→0); 2. large Jordan block matrices as the dimension of the matrix gets large (N→∞). In case 1 we are going to consider the operator Ph subject to small Gaussian random perturbations. We let the perturbation coupling constant δ be e (-1/Ch) ≤ δ ⩽ h(k), for constants C, k > 0 suitably large. Let ∑ be the closure of the range of the principal symbol. Previous results o…

Opérateurs non-auto-adjointsSemiclassical differential operatorsThéorie spectraleOpérateurs différentiels semiclassique[MATH.MATH-SP] Mathematics [math]/Spectral Theory [math.SP]Random perturbationsSpectral theoryNon-self-adjoint operatorsPerturbations aléatoires
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Operators on Partial Inner Product Spaces: Towards a Spectral Analysis

2014

Given a LHS (Lattice of Hilbert spaces) $V_J$ and a symmetric operator $A$ in $V_J$, in the sense of partial inner product spaces, we define a generalized resolvent for $A$ and study the corresponding spectral properties. In particular, we examine, with help of the KLMN theorem, the question of generalized eigenvalues associated to points of the continuous (Hilbertian) spectrum. We give some examples, including so-called frame multipliers.

Partial inner product spacesPure mathematicsGeneral MathematicsFOS: Physical sciencesresolventLattice (discrete subgroup)01 natural sciencessymbols.namesakeInner product spaceSettore MAT/05 - Analisi MatematicaPIP-spaceframe multipliers}lattices of Hilbert spacesSpectral analysis0101 mathematicsEigenvalues and eigenvectorsMathematical PhysicsMathematicsResolventframe multipliers010102 general mathematicsSpectrum (functional analysis)Spectral propertiesHilbert spaceMathematical Physics (math-ph)010101 applied mathematicssymbolsspectral properties of symmetric operatorsSpectral theory46Cxx 47A10 47B37
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A case study on gamified interventions for team cohesion in factory work

2018

In this article, we aim to provide insights into the design and implementation of game elements for teamwork on the work floor and to study their effect. Inventing games to break monotonous jobs is a long-standing practice, yet conscious implementation of motivational elements of games at work is a recent phenomenon. Generally, gamification is used to enhance individual performance; it may be effective in enhancing teamwork as well. We developed game elements aimed at team cohesion and examined the effect of two gamified interventions (team performance feedback and personal profiles) on team cohesion in a factory. Results suggest that the interventions mainly raised attention toward the asp…

Performance feedbackTeamworklcsh:T58.5-58.64Social Psychologylcsh:Information technologyCommunicationmedia_common.quotation_subject05 social sciencesApplied psychologyPsychological interventionCohesion (computer science)team cohesionHuman-Computer Interaction0502 economics and business0501 psychology and cognitive sciencesgamificationfactory operatorsPsychology050203 business & management050107 human factorsapplied design researchmedia_common
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A characterization of absolutely summing operators by means of McShane integrable functions

2004

AbstractAbsolutely summing operators between Banach spaces are characterized by means of McShane integrable functions.

Pettis integralPure mathematicsMathematics::Functional AnalysisMcShane integralIntegrable systemStatistics::ApplicationsApplied MathematicsMathematical analysisBanach spaceCharacterization (mathematics)Absolutely summing operatorSettore MAT/05 - Analisi MatematicaPettis integralabsolutely summing operatorsAnalysisMathematics
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On weakly measurable stochastic processes and absolutely summing operators

2006

A characterization of absolutely summing operators by means of McShane integrable stochastic processes is considered

Pettis integralSettore MAT/05 - Analisi MatematicaStochastic processGeneral MathematicsMathematical analysisApplied mathematicsPettis integral McShane integral amart uniform amart absolutely summing operatorsMathematicsMathematica Bohemica
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