Search results for " partial"

showing 10 items of 356 documents

Time Evolution of Partial Discharges in a Dielectric Subjected to the DC Periodic Voltage

2022

Partial discharge (PD) detection can be considered one of the most useful tools for assessing the insulation conditions of the power apparatus in high-voltage systems. Under AC conditions, this analysis is widely employed in online and offline tests, such as type tests or commissioning, and can be carried out by applying the phase-resolved PD (PRPD) method, since the patterns can give information about the defect classification. Under DC voltages, the classic pattern recognition method cannot be performed, and the measurements show complexities related to the nature of the phenomena. For this reason, to date, a standard for PD measurements under DC does not exist. In previous papers, a new …

Direct current periodic (DCP)partial discharge (PD); direct current periodic (DCP); partial discharge measurements; HVDC; DCSettore ING-IND/31 - ElettrotecnicaControl and OptimizationHVDCRenewable Energy Sustainability and the EnvironmentEnergy Engineering and Power TechnologyElectrical and Electronic EngineeringPartial discharge (PD)Engineering (miscellaneous)DCEnergy (miscellaneous)Partial discharge measurementsEnergies; Volume 15; Issue 6; Pages: 2052
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Regularity of renormalized solutions to nonlinear elliptic equations away from the support of measure data

2018

We prove boundedness and continuity for solutions to the Dirichlet problem for the equation $$ - {\rm{div}}(a(x,\nabla u)) = h(x,u) + \mu ,\;\;\;\;\;{\rm{in}}\;{\rm{\Omega }} \subset \mathbb{R}^{N},$$ where the left-hand side is a Leray-Lions operator from $$- {W}^{1,p}_0(\Omega)$$ into W−1,p′(Ω) with 1 < p < N, h(x,s) is a Caratheodory function which grows like ∣s∣p−1 and μ is a finite Radon measure. We prove that renormalized solutions, though not globally bounded, are Holder-continuous far from the support of μ.

Dirichlet problemElliptic partial differential equations; boundary-value problems; regularity; Hölder-continuityregularityOperator (physics)boundary-value problemsElliptic partial differential equationsHölder-continuityMeasure (mathematics)OmegaCombinatoricsBounded functionRadon measurep-LaplacianNabla symbolMathematics
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Existence and uniqueness of a solution for a parabolic quasilinear problem for linear growth functionals with $L^1$ data

2002

We introduce a new concept of solution for the Dirichlet problem for quasilinear parabolic equations in divergent form for which the energy functional has linear growth. Using Kruzhkov's method of doubling variables both in space and time we prove uniqueness and a comparison principle in $L^1$ for these solutions. To prove the existence we use the nonlinear semigroup theory.

Dirichlet problemNonlinear systemSpacetimeSemigroupGeneral MathematicsMathematical analysisMathematics::Analysis of PDEsUniquenessLinear growthParabolic partial differential equationMathematicsEnergy functionalMathematische Annalen
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Fully representable and*-semisimple topological partial*-algebras

2012

We continue our study of topological partial *-algebras, focusing our attention to *-semisimple partial *-algebras, that is, those that possess a {multiplication core} and sufficiently many *-representations. We discuss the respective roles of invariant positive sesquilinear (ips) forms and representable continuous linear functionals and focus on the case where the two notions are completely interchangeable (fully representable partial *-algebras) with the scope of characterizing a *-semisimple partial *-algebra. Finally we describe various notions of bounded elements in such a partial *-algebra, in particular, those defined in terms of a positive cone (order bounded elements). The outcome …

Discrete mathematics*-semisimple partial *-algebrasPure mathematicsbounded elements.*-semisimple partial *-algebraGeneral MathematicsMathematics - Rings and AlgebrasTopology08A55 46K05 46K10 47L60bounded elements}topological partial *-algebrasRings and Algebras (math.RA)Settore MAT/05 - Analisi MatematicaBounded functionFOS: MathematicsInvariant (mathematics)topological partial *-algebraMathematicsStudia Mathematica
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Common Fixed points for multivalued generalized contractions on partial metric spaces

2013

We establish some common fixed point results for multivalued mappings satisfying generalized contractive conditions on a complete partial metric space. The presented theorems extend some known results to partial metric spaces. We motivate our results by some given examples and an application for finding the solution of a functional equation arising in dynamic programming.

Discrete mathematicsAlgebra and Number TheoryApplied MathematicsInjective metric spaceFubini–Study metricIntrinsic metricConvex metric spaceComputational MathematicsMetric spaceSettore MAT/05 - Analisi MatematicaMetric (mathematics)Geometry and TopologyCommon fixed point partial metric space partial Hausdorff metric weak contraction.Metric differentialAnalysisFisher information metricMathematics
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On the symbol homomorphism of a certain Frechet algebra of singular integral operators

1985

We prove the surjectivity of the symbol map of the Frechet algebra obtained by completing an algebra of convolution and multiplication operators in the topology generated by all L2-Sobolev norms. The proof is based on an ℝn of Egorov's theorem valid for non-homogeneous principal symbols, discussed in [5], [6]. We use the hyperbolic equation ∂u/∂t=i|D|ηu, 0<η<1, which has its characteristic flow constant at infinity, so that no differentiability of the symbol is required there.

Discrete mathematicsAlgebra and Number TheoryFlow (mathematics)HomomorphismDifferentiable functionFréchet algebraConstant (mathematics)Symbol (formal)Hyperbolic partial differential equationAnalysisConvolutionMathematicsIntegral Equations and Operator Theory
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A note on best approximation in 0-complete partial metric spaces

2014

We study the existence and uniqueness of best proximity points in the setting of 0-complete partial metric spaces. We get our results by showing that the generalizations, which we have to consider, are obtained from the corresponding results in metric spaces. We introduce some new concepts and consider significant theorems to support this fact.

Discrete mathematicsArticle SubjectApplied MathematicsInjective metric spacelcsh:MathematicsT-normlcsh:QA1-939Intrinsic metricConvex metric spaceUniform continuityMetric spaceFréchet spaceSettore MAT/05 - Analisi Matematica0-completeness best proximity point fixed point partial metric spaceMetric (mathematics)AnalysisMathematics
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Coupled fixed point, F-invariant set and fixed point of N-order

2010

‎In this paper‎, ‎we establish some new coupled fixed point theorems in complete metric spaces‎, ‎using a new concept of $F$-invariant set‎. ‎We introduce the notion of fixed point of $N$-order as natural extension of that of coupled fixed point‎. ‎As applications‎, ‎we discuss and adapt the presented results to the setting of partially ordered cone metric spaces‎. ‎The presented results extend and complement some known existence results from the literature‎.

Discrete mathematicsCoupled fixed point F-invariant set fixed point of N-order partially ordered set cone metric spaceControl and OptimizationAlgebra and Number Theory47H10‎Fixed-point theoremFixed pointFixed-point propertyCoupled fixed point‎partially ordered setLeast fixed point‎$F$-invariant set54H25Schauder fixed point theoremFixed-point iterationSettore MAT/05 - Analisi Matematica‎34B15‎cone metric space‎fixed point of $N$-orderKakutani fixed-point theoremAnalysisHyperbolic equilibrium pointMathematics
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A homotopy fixed point theorem in 0-complete partial metric space

2015

We generalize a result of Feng and Liu, on multi-valued contractive mappings, for studying the relationship between fixed point sets and homotopy fixed point sets. The presented results are discussed in the generalized setting of 0-complete partial metric spaces. An example and a nonlinear alternative of Leray-Schauder type are given to support our theorems.

Discrete mathematicsHomotopic mappings multi-valued mappings partial metric spacesGeneral MathematicsHomotopyFixed-point theoremProduct metricFixed pointType (model theory)Nonlinear systemMetric spaceSettore MAT/05 - Analisi MatematicaSettore MAT/03 - GeometriaCoincidence pointMathematics
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Common fixed points for self-mappings on partial metric spaces

2012

Abstract In this paper, we prove some results of a common fixed point for two self-mappings on partial metric spaces. Our results generalize some interesting results of Ilić et al. (Appl. Math. Lett. 24:1326-1330, 2011). We conclude with a result of the existence of a fixed point for set-valued mappings in the context of 0-complete partial metric spaces. MSC:54H25, 47H10.

Discrete mathematicsInjective metric spaceApplied Mathematics010102 general mathematicsEquivalence of metricscommon fixed point01 natural sciencesConvex metric spaceIntrinsic metric010101 applied mathematicsMetric spacepoints of coincidence0-complete partial metric spaceSettore MAT/05 - Analisi Matematicaψ-contractions.Metric (mathematics)Metric mapGeometry and Topology0101 mathematicsCoincidence pointMathematicsFixed Point Theory and Applications
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