Search results for "Functional analysis"

showing 10 items of 1059 documents

Fréchet Spaces of Holomorphic Functions without Copies of l 1

1996

Let X be a Banach space. Let Hw*(X*) the Frechet space whose elements are the holomorphic functions defined on X* whose restrictions to each multiple mB(X*), m = 1,2, …, of the closed unit ball B(X*) of X* are continuous for the weak-star topology. A fundamental system of norms for this space is the supremum of the absolute value of each element of Hw*(X*) in mB(X*), m = 1,2,…. In this paper we construct the bidual of l1 when this space contains no copy of l1. We also show that if X is an Asplund space, then Hw*(X*) can be represented as the projective limit of a sequence of Banach spaces that are Asplund.

CombinatoricsUnit sphereMathematics::Functional AnalysisIsolated pointFréchet spaceGeneral MathematicsMathematical analysisHolomorphic functionBanach spaceInfinite-dimensional holomorphySpace (mathematics)Asplund spaceMathematicsMathematische Nachrichten
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Thin Points of Brownian Motion Intersection Local Times

2005

Let \(\ell \) be the projected intersection local time of two independent Brownian paths in \(\mathbb{R}^d \) for d = 2, 3. We determine the lower tail of the random variable \(\ell \)(B(0, 1)), where B(0, 1) is the unit ball. The answer is given in terms of intersection exponents, which are explicitly known in the case of planar Brownian motion. We use this result to obtain the multifractal spectrum, or spectrum of thin points, for the intersection local times.

CombinatoricsUnit spherePhysicssymbols.namesakeIntersectionLocal timeSpectrum (functional analysis)symbolsHausdorff measureWiener sausageTopologyRandom variableBrownian motion
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A Lebesgue-type decomposition for non-positive sesquilinear forms

2018

A Lebesgue-type decomposition of a (non necessarily non-negative) sesquilinear form with respect to a non-negative one is studied. This decomposition consists of a sum of three parts: two are dominated by an absolutely continuous form and a singular non-negative one, respectively, and the latter is majorized by the product of an absolutely continuous and a singular non-negative forms. The Lebesgue decomposition of a complex measure is given as application.

Complex measurePure mathematicsSesquilinear formType (model theory)Lebesgue integration01 natural sciencesRegularitysymbols.namesakeSettore MAT/05 - Analisi MatematicaLebesgue decomposition0103 physical sciencesDecomposition (computer science)Complex measureFOS: Mathematics0101 mathematicsMathematicsMathematics::Functional AnalysisSingularitySesquilinear formApplied Mathematics010102 general mathematicsAbsolute continuityFunctional Analysis (math.FA)Mathematics - Functional Analysis47A07 15A63 28A12 47A12Product (mathematics)symbols010307 mathematical physicsNumerical range
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A note on Fréchet and approximate subdifferentials of composite functions

1994

The aim of this note is to present in the reflexive Banach space setting a natural and simple proof of the formula of the approximate subdifferential of a composite function.

Composite functionMathematics::Functional AnalysisPure mathematicsSimple (abstract algebra)General MathematicsComposite numberBanach spaceSubderivativeMathematicsBulletin of the Australian Mathematical Society
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Vertical spectrum of the C2H 2+ system. An open shell (SC)2-CAS-SDCI study

2003

The open shell (SC)(2)-CAS-SDCI method along with a basis set of atomic natural orbitals (ANO) has been applied for calculating the main ionization potentials of acetylene, as well as the manifold of excited states of the different symmetries up to 32 eV. In this method, the single and double excitations of a CAS space are generated and the corresponding CI matrix is corrected by means of the (SC)(2) procedure that cancels the size-extensivity error and adds some high order contributions. The mean absolute error for the outer-valence X (2)Pi(u)(1pi(u) (-1)), A (2)Sigma(g) (+)(3sigma(g) (-1)), and B (2)Sigma(u) (+)(2sigma(u) (-1)) states, and the inner-valence C (2)Sigma(g) (+)(2sigma(g) (-1…

Computational MathematicsChemistryExcited stateSigmaGeneral ChemistryState (functional analysis)Complete active spaceAtomic physicsConfiguration interactionWave functionOpen shellBasis setJournal of Computational Chemistry
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Modeling and Performance Analysis of Channel Assembling in Multichannel Cognitive Radio Networks With Spectrum Adaptation

2012

[EN] To accommodate spectrum access in multichannel cognitive radio networks (CRNs), the channel-assembling technique, which combines several channels together as one channel, has been proposed in many medium access control (MAC) protocols. However, analytical models for CRNs enabled with this technique have not been thoroughly investigated. In this paper, two representative channel-assembling strategies that consider spectrum adaptation and heterogeneous traffic are proposed, and the performance of these strategies is evaluated based on the proposed continuous-time Markov chain (CTMC) models. Moreover, approximations of these models in the quasistationary regime are analyzed, and closed-fo…

Computer Networks and CommunicationsComputer scienceAerospace EngineeringMarkov process02 engineering and technologyContinuous-time Markov chain (CTMC) modelsChannel assemblingsymbols.namesake0203 mechanical engineering0202 electrical engineering electronic engineering information engineeringCognitive radio networks (CRNs)Electrical and Electronic EngineeringAdaptation (computer science)SimulationMarkov chainPerformance analysisSpectrum (functional analysis)020206 networking & telecommunications020302 automobile design & engineeringINGENIERIA TELEMATICACognitive radioAutomotive EngineeringsymbolsSpectrum adaptationAlgorithmCommunication channelIEEE Transactions on Vehicular Technology
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Lazy consensus for networks with unknown but bounded disturbances

2007

We consider stationary consensus protocols for networks of dynamic agents. The measure of the neighbors' state is affected by Unknown But Bounded disturbances. Here the main contribution is the formulation and solution of what we call the isin-consensus problem, where the states are required to converge in a tube of ray isin asymptotically or in finite time.

Computer Science::Multiagent SystemsDynamic agentsLazy consensusComputer scienceControl theoryMulti-agent systemBounded functionDynamic agents; Lazy consensus; Stationary consensus protocolsState (functional analysis)Stationary consensus protocolsTopologyMeasure (mathematics)Uniform consensus2007 46th IEEE Conference on Decision and Control
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Rejection-Free Monte Carlo

2019

So far, we have been using the rejection Monte Carlo algorithms. To remind us, the algorithms proceed from state x to possible state \(x'\) as outlined in Algorithm 1.

Computer scienceMonte Carlo methodStatistical physicsState (functional analysis)
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Prediction of Hidden Oscillations Existence in Nonlinear Dynamical Systems: Analytics and Simulation

2013

From a computational point of view, in nonlinear dynamical systems, attractors can be regarded as self-excited and hidden attractors. Self-excited attractors can be localized numerically by a standard computational procedure, in which after a transient process a trajectory, starting from a point of unstable manifold in a neighborhood of equilibrium, reaches a state of oscillation, therefore one can easily identify it. In contrast, for a hidden attractor, a basin of attraction does not intersect neighborhoods of equilibria. While classical attractors are self-excited, attractors can therefore be obtained numerically by the standard computational procedure, for localization of hidden attracto…

Computer scienceOscillationbusiness.industryProcess (computing)State (functional analysis)Machine learningcomputer.software_genreManifoldNonlinear Sciences::Chaotic DynamicsAttractorTrajectoryPoint (geometry)Transient (oscillation)Artificial intelligenceStatistical physicsbusinesscomputer
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Dynamic Channel Aggregation Strategies in Cognitive Radio Networks with Spectrum Adaptation

2011

In cognitive radio networks, channel aggregation techniques which combine several channels together as one channel have been proposed in many MAC protocols. In this paper, spectrum adaptation is proposed in channel aggregation and two strategies which dynamically adjust channel occupancy of ongoing traffic flows are further developed. The performance of these strategies is evaluated using continuous time Markov chain models. Moreover, models in the quasi-stationary regime are analyzed and the closed-form capacity expression is derived in this regime. Numerical results demonstrate that the capacity of the secondary network can be improved by using channel aggregation with spectrum adaptation.

Computer sciencebusiness.industrySpectrum (functional analysis)Markov processUpper and lower boundsExpression (mathematics)symbols.namesakeCognitive radiosymbolsAdaptation (computer science)businessComputer Science::Information TheoryCommunication channelComputer network2011 IEEE Global Telecommunications Conference - GLOBECOM 2011
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