Search results for "Derivative"

showing 10 items of 1074 documents

Dynamic analysis for axially moving viscoelastic panels

2012

In this study, stability and dynamic behaviour of axially moving viscoelastic panels are investigated with the help of the classical modal analysis. We use the flat panel theory combined with the Kelvin–Voigt viscoelastic constitutive model, and we include the material derivative in the viscoelastic relations. Complex eigenvalues for the moving viscoelastic panel are studied with respect to the panel velocity, and the corresponding eigenfunctions are found using central finite differences. The governing equation for the transverse displacement of the panel is of fifth order in space, and thus five boundary conditions are set for the problem. The fifth condition is derived and set at the in-…

Constitutive equationDynamicMaterial derivative02 engineering and technology01 natural sciencesViscoelasticityDisplacement (vector)Physics::Fluid DynamicsViscositystabiilius0203 mechanical engineeringMaterials Science(all)viscoelasticModelling and Simulation0103 physical sciencesGeneral Materials ScienceBoundary value problemta216010301 acousticsMathematicsViscoelasticdynamicominaisarvotMechanical EngineeringApplied MathematicsLiikkuvapalkkiFlexural rigidityBeamEigenvaluesMechanicsviscoelastinenstabilityCondensed Matter Physics020303 mechanical engineering & transportsdynaaminenMechanics of MaterialsModeling and SimulationBending stiffnessbeamMovingliikkuminenStabilityInternational Journal of Solids and Structures
researchProduct

A fractional order theory of poroelasticity

2019

Abstract We introduce a time memory formalism in the flux-pressure constitutive relation, ruling the fluid diffusion phenomenon occurring in several classes of porous media. The resulting flux-pressure law is adopted into the Biot’s formulation of the poroelasticity problem. The time memory formalism, useful to capture non-Darcy behavior, is modeled by the Caputo’s fractional derivative. We show that the time-evolution of both the degree of settlement and the pressure field is strongly influenced by the order of Caputo’s fractional derivative. Also a numerical experiment aiming at simulating the confined compression test poroelasticity problem of a sand sample is performed. In such a case, …

Constitutive equationPoromechanics02 engineering and technology01 natural sciencesPressure fieldDarcy–Weisbach equationPhysics::Geophysics010305 fluids & plasmas0203 mechanical engineeringFractional operators0103 physical sciencesCaputo's fractional derivative; Fractional operators; PoroelasticityApplied mathematicsGeneral Materials ScienceCaputo's fractional derivative Fractional operators PoroelasticityCaputo's fractional derivativeCivil and Structural EngineeringMathematicsOrder theoryBiot numberMechanical EngineeringPoroelasticityCondensed Matter PhysicsFractional calculus020303 mechanical engineering & transportsMechanics of MaterialsFractional operatorSettore ICAR/08 - Scienza Delle CostruzioniPorous medium
researchProduct

Risk Disclosure in the European Banking Industry: Qualitative and Quantitative Content Analysis Methodologies

2022

This book aims to shed light on the advantages and disadvantages of both qualitative and quantitative content analysis methodologies by examining risk disclosure practices in the European banking industry. Content analysis methodologies allow to assess the level of transparency of financial and non-financial reports by focusing on the information disclosed to the public with reference to their risk exposure and management. There is an ongoing debate in the literature to understand whether qualitative or quantitative content analysis methodologies are more effective and useful to analyse disclosure practices. Some authors contend that qualitative methodologies may be more appropriate because…

Content AnalysisBanking UnionDerivative DisclosureSingle Supervisory MechanismSettore SECS-P/11 - Economia Degli Intermediari FinanziariDisclosureBankingEuropean BankBanking Supervision
researchProduct

An evolutionary method for complex-process optimization

2010

10 páginas, 7 figuras, 7 tablas

Continuous optimizationMathematical optimizationOptimization problemGeneral Computer ScienceEvolutionary algorithmMetaheuristicsManagement Science and Operations ResearchEvolutionary algorithmsMulti-objective optimizationComplex-process optimizationContinuous optimizationModeling and SimulationGenetic algorithmDerivative-free optimizationGlobal optimizationMulti-swarm optimizationMetaheuristicMathematicsComputers & Operations Research
researchProduct

Locally Convex Quasi *-Algebras of Operators

2011

This note is mainly concerned with locally convex quasi C*-normed *-algebras which arise as completions of C*-algebras of operators under certain topologies. Their importance is made clear by the representation theory of abstract locally convex quasi C*-normed *-algebras, investigated in previous papers and whose basic aspects are also overviewed here.

Convex analysisDiscrete mathematicsQuasi *-algebrasPure mathematicsApplied MathematicsRegular polygonSubderivativeOperator theoryNetwork topologyRepresentation theoryComputational MathematicsComputational Theory and MathematicsSettore MAT/05 - Analisi MatematicaOperatorMathematicsComplex Analysis and Operator Theory
researchProduct

Fixed point theory for almost convex functions

1998

Traditionally, metric fixed point theory has sought classes of spaces in which a given type of mapping (nonexpansive, assymptotically or generalized nonexpansive, uniformly Lipschitz, etc.) from a nonempty weakly compact convex set into itself always has a fixed point. In some situations the class of space is determined by the application while there is some degree of freedom in constructing the map to be used. With this in mind we seek to relax the conditions on the space by considering more restrictive types of mappings.

Convex analysisLeast fixed pointPure mathematicsApplied MathematicsMathematical analysisConvex setSubderivativeAbsolutely convex setFixed pointKakutani fixed-point theoremFixed-point propertyAnalysisMathematics
researchProduct

Non absolutely convergent integrals of functions taking values in a locally convex space

2006

Properties of McShane and Kurzweil-Henstock integrable functions taking values in a locally convex space are considered and the relations with other integrals are studied. A convergence theorem for the Kurzweil-Henstock integral is given

Convex analysisMcShane integralGeneral MathematicsMathematical analysisConvex setProper convex functionSubderivativeKurzweil-Henstock integralChoquet theory28B05McShaneintegral Pettis integralSettore MAT/05 - Analisi MatematicaLocally convex topological vector spacelocally convex spacesPettis integralConvex combinationAbsolutely convex setMathematics46G10
researchProduct

Riemann type integrals for functions taking values in a locally convex space

2006

The McShane and Kurzweil-Henstock integrals for functions taking values in a locally convex space are defined and the relations with other integrals are studied. A characterization of locally convex spaces in which Henstock Lemma holds is given.

Convex analysisPure mathematicsGeneral MathematicsMathematical analysisMathematics::Classical Analysis and ODEsProper convex functionConvex setSubderivativeChoquet theoryLocally convex topological vector spaceConvex combinationPettis integral McShane integral Kurzweil-Henstock integral locally convex spacesAbsolutely convex setMathematicsCzechoslovak Mathematical Journal
researchProduct

On some close to convex functions with negative coefficients

2007

In this paper we propose for study a class of close to convex functions with negative coefficients defined by using a modified Salagean operator. .

Convex hullConvex analysisPure mathematicsGeneral MathematicsMathematical analysisConvex optimizationConvex setProper convex functionConvex combinationSubderivativeConvex conjugateMathematicsFilomat
researchProduct

An upper bound for nonlinear eigenvalues on convex domains by means of the isoperimetric deficit

2010

We prove an upper bound for the first Dirichlet eigenvalue of the p-Laplacian operator on convex domains. The result implies a sharp inequality where, for any convex set, the Faber-Krahn deficit is dominated by the isoperimetric deficit.

Convex hullConvex analysisp-Laplace operatorGeneral MathematicsMathematical analysisConvex setDirichlet eigenvalueSubderivativeMathematics::Spectral TheoryCombinatoricsupper boundsSettore MAT/05 - Analisi MatematicaConvex polytopeConvex combinationAbsolutely convex setIsoperimetric inequalityMathematics
researchProduct