Search results for "Measure"

showing 10 items of 4687 documents

Probabilistic limit identification up to “small” sets

1996

In this paper we study limit identification of total recursive functions in the case when “small” sets of errors are allowed. Here the notion of “small” sets we formalize in a very general way, i.e. we define a notion of measure for subsets of natural numbers, and we consider as being small those sets, which are subsets of sets with zero measure.

Discrete mathematicsIdentification (information)Zero (complex analysis)Recursive functionsNatural numberLimit (mathematics)Measure (mathematics)Mathematics
researchProduct

VECTOR-VALUED FUNCTIONS INTEGRABLE WITH RESPECT TO BILINEAR MAPS

2008

Let $(\Omega, \Sigma, \mu)$ be a $\sigma-$finite measure space, $1\le p \lt \infty$, $X$ be a Banach space $X$ and ${\cal B} :X\times Y \to Z$ be a bounded bilinear map. We say that an $X$-valued function $f$ is $p-$integrable with respect to ${\cal B}$ whenever $\sup\{\int_\Omega\|{\cal B}(f(w),y)\|^pd\mu: \|y\|=1\}$ is finite. We identify the spaces of functions integrable with respect to the bilinear maps arising from H\"older's and Young's inequalities. We apply the theory to give conditions on $X$-valued kernels for the boundedness of integral operators $T_{{\cal B}}(f) (w)=\int_{\Omega'}{{\cal B}}(k(w,w'),$ $f(w'))d\mu'(w')$ from ${\mathrm L}^p(Y)$ into ${\mathrm L}^p(Z)$, extending t…

Discrete mathematicsIntegrable systemGeneral MathematicsBanach spaceFunction (mathematics)Space (mathematics)Measure (mathematics)Omegavector-valued functionsbilinear mapBounded function42B3047B35Vector-valued functionMathematics
researchProduct

An integral representation for decomposable measures of measurable functions

1994

We start with a measurem on a measurable space (Ω,A), decomposable with respect to an Archimedeant-conorm ⊥ on a real interval [0,M], which generalizes an additive measure. Using the integral introduced by the second author, a Radon-Nikodym type theorem, needed in what follows, is given.

Discrete mathematicsIntegral representationMarkov kernelMeasurable functionApplied MathematicsGeneral MathematicsDiscrete Mathematics and CombinatoricsInterval (graph theory)Type (model theory)Space (mathematics)Measure (mathematics)MathematicsAequationes Mathematicae
researchProduct

A property of connected Baire spaces

1997

Abstract We give a topological version of a classical result of F. Sunyer Balaguer's on a local characterization of real polynomials. This is done by studying a certain property on a class of connected Baire spaces, thus allowing us to obtain a local characterization of repeated integrals of analytic maps on Banach spaces.

Discrete mathematicsLocally connectedBanach spaceBaire category theoremGeometry and TopologyBaire spaceBaire spaceOpen mapping theorem (functional analysis)Baire measureSunyer Balaguer's TheoremComplete metric spaceMathematicsTopology and its Applications
researchProduct

On some parameters related to weak noncompactness in L1(μ,E)

2009

Abstract A weak measure of noncompactness γU is defined in a Banach space in terms of convex compactness. We obtain relationships between the measure γU (A) of a bounded set A in the Bochner space L1 (μ,E) and two parameters Π(A) and Δ1(A). Then the criterion for relative weak compactness due to Ulger [19] and Diestel-Ruess-Schachermayer [11] is recovered.

Discrete mathematicsMathematics (miscellaneous)Compact spaceBounded setBochner integralRegular polygonBanach spaceBochner spaceMeasure (mathematics)MathematicsQuaestiones Mathematicae
researchProduct

The pianigiani-yorke measure for topological markov chains

1997

We prove the existence of a Pianigiani-Yorke measure for a Markovian factor of a topological Markov chain. This measure induces a Gibbs measure in the limit set. The proof uses the contraction properties of the Ruelle-Perron-Frobenius operator.

Discrete mathematicsMathematics::Dynamical SystemsMarkov chain mixing timeMarkov chainGeneral MathematicsMarkov processPartition function (mathematics)TopologyHarris chainNonlinear Sciences::Chaotic Dynamicssymbols.namesakeBalance equationsymbolsExamples of Markov chainsGibbs measureMathematicsIsrael Journal of Mathematics
researchProduct

Finitely randomized dyadic systems and BMO on metric measure spaces

2015

Abstract We study the connection between BMO and dyadic BMO in metric measure spaces using finitely randomized dyadic systems, and give a Garnett–Jones type proof for a theorem of Uchiyama on a construction of certain BMO functions. We obtain a relation between the BMO norm of a suitable expectation over dyadic systems and the dyadic BMO norms of the original functions in different systems. The expectation is taken over only finitely randomized dyadic systems to overcome certain measurability questions. Applying our result, we derive Uchiyama’s theorem from its dyadic counterpart, which we also prove.

Discrete mathematicsMathematics::Functional AnalysisDyadic cubeApplied Mathematicsta111Mathematics::Analysis of PDEsMathematics::Classical Analysis and ODEsMetric measure spaceBounded mean oscillationQuantitative Biology::OtherBounded mean oscillationRandomized dyadic systemMetric spaceNorm (mathematics)Dyadic BMOAnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
researchProduct

Injective spaces of real-valued functions with the baire property

1995

Generalizing the technique used by S.A. Argyros in [3], we give a lemma from which certain Banach spaces are shown to be non-injective. This is applied mainly to study the injectivity of spaces of real-valued Borel functions and functions with the Baire property on a topological space. The results obtained in this way do not follow from previous works about this matter.

Discrete mathematicsMathematics::Functional AnalysisFréchet spaceGeneral MathematicsTopological tensor productMathematics::General TopologyInterpolation spaceBaire category theoremOpen mapping theorem (functional analysis)Baire measureTopological vector spaceComplete metric spaceMathematicsIsrael Journal of Mathematics
researchProduct

Quasi-pseudometric properties of the Nikodym-Saks space

2003

[EN] For a non-negative finite countably additive measure μ defined on the σ-field Σ of subsets of Ω, it is well known that a certain quotient of Σ can be turned into a complete metric space Σ (Ω), known as the Nikodym-Saks space, which yields such important results in Measure Theory and Functional Analysis as Vitali-Hahn-Saks and Nikodym's theorems. Here we study some topological properties of Σ (Ω) regarded as a quasi-pseudometric space.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsFunctional analysislcsh:MathematicsQuasi-pseudometric spaceMathematics::General Topologylcsh:QA299.6-433lcsh:AnalysisPseudometric spacelcsh:QA1-939Space (mathematics)Measure (mathematics)Complete metric spaceNikodym-Saks spaceGeometry and TopologyQuotientMathematicsApplied General Topology
researchProduct

Closedness and lower semicontinuity of positive sesquilinear forms

2009

The relationship between the notion of closedness, lower semicontinuity and completeness (of a quotient) of the domain of a positive sesquilinear form defined on a subspace of a topological vector space is investigated and sufficient conditions for their equivalence are given.

Discrete mathematicsMathematics::Functional AnalysisPure mathematicsMathematics::Operator AlgebrasSesquilinear formGeneral MathematicsMathematics::Optimization and ControlMathematics::General TopologyClosedness Semicontinuity Sesquilinear formsDomain (mathematical analysis)Topological vector spaceSettore MAT/05 - Analisi MatematicaAlgebra over a fieldCompleteness (statistics)Equivalence (measure theory)Subspace topologyQuotientMathematicsRendiconti del Circolo Matematico di Palermo
researchProduct