Search results for "operators"

showing 10 items of 228 documents

Existence of fixed points and measures of weak noncompactness

2009

Abstract The purpose of this paper is to study the existence of fixed points by using measures of weak noncompactness. Later on, we provide an existence principle for solutions for a nonlinear integral equation.

Applied MathematicsMathematical analysisFixed pointNonlinear integral equationIntegral equationAnalysisNonlinear operatorsMathematicsNonlinear Analysis: Theory, Methods & Applications
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On the Measure of Many-Level Fuzzy Rough Approximation for L-Fuzzy Sets

2019

We introduce a many-level version of L-fuzzy rough approximation operators and define measures of approximation obtained by such operators. In a certain sense, theses measures characterize the quality of the resulting approximation. We study properties of such measures and give a topological interpretation of the obtained results.

Approximation operatorsFuzzy setApplied mathematicsFuzzy logicMeasure (mathematics)MathematicsInterpretation (model theory)
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Solution of an initial-value problem for parabolic equations via monotone operator methods

2014

We study a general initial-value problem for parabolic equations in Banach spaces, by using a monotone operator method. We provide sufficient conditions for the existence of solution to such problem.

Banach spacemetric spacesparabolic equationlcsh:Mathematicsmetric spaceMathematicsofComputing_NUMERICALANALYSISparabolic equationstransitive relationslcsh:QA1-939Banach spacestransitive relations.Settore MAT/05 - Analisi Matematicamonotone operatormonotone operatorsElectronic Journal of Differential Equations
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MR2986428 Lebedev, Leonid P.(CL-UNC); Vorovich, Iosif I.; Cloud, Michael J. Functional analysis in mechanics. Second edition. Springer Monographs in …

2014

Banach spaces Hilbert spaces bounded operators.Settore MAT/05 - Analisi Matematica
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Absolutely summing operators on C[0,1] as a tree space and the bounded approximation property

AbstractLet X be a Banach space. For describing the space P(C[0,1],X) of absolutely summing operators from C[0,1] to X in terms of the space X itself, we construct a tree space ℓ1tree(X) on X. It consists of special trees in X which we call two-trunk trees. We prove that P(C[0,1],X) is isometrically isomorphic to ℓ1tree(X). As an application, we characterize the bounded approximation property (BAP) and the weak BAP in terms of X∗-valued sequence spaces.

Banach spacesAbsolutely summing operatorsTwo-trunk treesContinuous functions on [01]Linear B-splinesBounded approximation propertiesJournal of Functional Analysis
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On the Bishop-Phelps-Bollobás type theorems

2017

This dissertation is devoted to the study of the Bishop-Phelps-Bollobás property in different contexts. In Chapter 1 we give a historical resume and the motivation behind this property as the classics Bishop-Phelps and Bishop-Phelps-Bollobás theorems. We define the Bishop-Phelps-Bollobás property (BPBp) and we comment on some important current results. In Chapter 2 we study similar properties to the BPBp. First, we define the Bishop-Phelps-Bollobás point property (BPBpp). The BPBpp is stronger than the BPBp. We study it for bounded linear operators and then for bilinear mappings. After that, we study two more similar properties: properties 1 and 2. Property 2 is just the dual property of th…

Bishop-Phelps-Bollobás property:MATEMÁTICAS [UNESCO]Mathematics::Functional AnalysisBishop-Phelps theoremNorm attaning operatorsUNESCO::MATEMÁTICAS
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Existence results and asymptotic behavior for nonlocal abstract Cauchy problems

2008

AbstractThe purpose of this paper is to study the existence and asymptotic behavior of solutions for Cauchy problems with nonlocal initial datum generated by accretive operators in Banach spaces.

Cauchy problemPure mathematicsm-Accretive operatorsNonlocal Cauchy problemsApplied MathematicsMathematical analysisBanach spaceMathematics::Analysis of PDEsGeodetic datumCauchy distributionIntegral solutionsAsymptotic behaviorAnalysisMathematicsJournal of Mathematical Analysis and Applications
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Exact treatment of operator difference equations with nonconstant and noncommutative coefficients

2013

We study a homogeneous linear second-order difference equation with nonconstant and noncommuting operator coefficients in a vector space. We build its exact resolutive formula consisting of the explicit noniterative expression of a generic term of the unknown sequence of vectors. Some nontrivial applications are reported in order to show the usefulness and the broad applicability of the result.

Cauchy problemSequenceDifferential equationGeneral MathematicsOperator (physics)Mathematical analysisGeneral EngineeringExpression (computer science)Term (logic)Noncommutative geometrySettore FIS/03 - Fisica Della MateriaCauchy problem Noncommuting operators Operator difference equationsMathematicsVector space
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(H, ρ)-induced dynamics and the quantum game of life

2017

Abstract We propose an extended version of quantum dynamics for a certain system S , whose evolution is ruled by a Hamiltonian H, its initial conditions, and a suitable set ρ of rules, acting repeatedly on S . The resulting dynamics is not necessarily periodic or quasi-periodic, as one could imagine for conservative systems with a finite number of degrees of freedom. In fact, it may have quite different behaviors depending on the explicit forms of H, ρ as well as on the initial conditions. After a general discussion on this (H, ρ)-induced dynamics, we apply our general ideas to extend the classical game of life, and we analyze several aspects of this extension.

Cellular automataPure mathematicsQuantum dynamicsFermionic operator01 natural sciences010305 fluids & plasmasModeling and simulationSpectral analysisymbols.namesakeQuantum games0103 physical sciencesSpectral analysis010306 general physicsSettore MAT/07 - Fisica MatematicaFinite setGame of lifeMathematicsMathematical physicsGame of lifeApplied MathematicsCellular automata Fermionic operators Game of life Heisenberg-like dynamics Spectral analysis Modeling and Simulation Applied MathematicsHeisenberg-like dynamicCellular automatonModeling and SimulationsymbolsHamiltonian (quantum mechanics)Applied Mathematical Modelling
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Some approximation properties by a class of bivariate operators

2019

WOS: 000503431300041

Class (set theory)Pure mathematicsGeneral MathematicsGBS-type operatorsmodulus of continuityGeneral EngineeringBernstein operatorsBivariate analysisModulus of continuityMathematics
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