Search results for "Ingenieurwissenschaften"

showing 5 items of 15 documents

Elastic waves propagation in 1D fractional non-local continuum

2008

Aim of this paper is the study of waves propagation in a fractional, non-local 1D elastic continuum. The non-local effects are modeled introducing long-range central body interactions applied to the centroids of the infinitesimal volume elements of the continuum. These non-local interactions are proportional to a proper attenuation function and to the relative displacements between non-adjacent elements. It is shown that, assuming a power-law attenuation function, the governing equation of the elastic waves in the unbounded domain, is ruled by a Marchaud-type fractional differential equation. Wave propagation in bounded domain instead involves only the integral part of the Marchaud fraction…

PhysicsNon-local elasticityContinuum mechanicsWave propagationDifferential equationMathematical analysisCondensed Matter PhysicsFractional calculuDispersion of elastic waves; Lattice models; Long-range interactions; Non-local elasticity; Fractional calculus; Fractional power lawPower lawAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsFractional calculusLattice modelLove waveLong-range interactionIngenieurwissenschaftenDispersion of elastic waveBounded functionddc:620Settore ICAR/08 - Scienza Delle CostruzioniLongitudinal waveFractional power law
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Field and numerical study of river confluence flow structures

2010

River hydrodynamics Turbulent open channel flow and transport phenomena

Physics::Fluid DynamicsPhysics::Space PhysicsIngenieurwissenschaften (620)Numerical simulation Large Eddy simulation HydrodynamicsPhysics::Atmospheric and Oceanic PhysicsComputer Science::Information TheoryPhysics::Geophysics
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A new representation of power spectral density and correlation function by means of fractional spectral moments

2009

In this paper, a new perspective for the representation of both the power spectral density and the correlation function by a unique class of function is introduced. We define the moments of order gamma (gamma being a complex number) of the one sided power spectral density and we call them Fractional Spectral Moments (FSM). These complex quantities remain finite also in the case in which the ordinary spectral moments diverge, and are able to represent the whole Power Spectral Density and the corresponding correlation function.

Power spectral density; Correlation function; Spectral moments; Fractional spectral moments; Generalized Taylor series; Fractional calculusMechanical EngineeringMathematical analysisPerspective (graphical)Stochastic ProcesseAerospace EngineeringSpectral densityOcean EngineeringStatistical and Nonlinear PhysicsMaximum entropy spectral estimationFunction (mathematics)Wind engineeringCondensed Matter PhysicsSpectral MomentFractional calculusCorrelation function (statistical mechanics)IngenieurwissenschaftenNuclear Energy and EngineeringEarthquake engineeringOrder (group theory)ddc:620Representation (mathematics)Settore ICAR/08 - Scienza Delle CostruzioniCivil and Structural EngineeringMathematics
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Fractional calculus approach to the statistical characterization of random variables and vectors

2009

Fractional moments have been investigated by many authors to represent the density of univariate and bivariate random variables in different contexts. Fractional moments are indeed important when the density of the random variable has inverse power-law tails and, consequently, it lacks integer order moments. In this paper, starting from the Mellin transform of the characteristic function and by fractional calculus method we present a new perspective on the statistics of random variables. Introducing the class of complex moments, that include both integer and fractional moments, we show that every random variable can be represented within this approach, even if its integer moments diverge. A…

Statistics and ProbabilityMellin transformStatistical Mechanics (cond-mat.stat-mech)Characteristic function (probability theory)Multivariate distributionMultivariate random variableMathematical analysisFOS: Physical sciencesMoment-generating functionCondensed Matter PhysicsFractional calculusFractional and complex moments; Multivariate distributions; Power-law tails; Inverse Mellin transformFractional and complex momentIngenieurwissenschaftenApplied mathematicsddc:620Inverse Mellin transformSettore ICAR/08 - Scienza Delle CostruzioniRandom variableCondensed Matter - Statistical MechanicsMathematicsInteger (computer science)Taylor expansions for the moments of functions of random variablesPower-law tail
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Photocrosslinkable polysaccharide hydrogel composites based on dextran or pullulan-amylose blends with cytokines for a human co-culture model of huma…

2016

Although a large body of research has been devoted to biomaterial development for bone tissue engineering and related medical disciplines in the last few years, novel and optimized materials especially for bone fractures of critical sizes demand continued development. In this respect, polysaccharide-based hydrogels demonstrate beneficial properties and fulfill the main requirements for a bone tissue scaffold as they are hydrophilic, biocompatible, and biodegradable. The aim of the present study was the development of a natural polysaccharide-based scaffold material that can integrate with the host tissue and support bone regeneration. For this purpose, we prepared and investigated two polym…

Stromal cellMaterials sciencemedicine.medical_treatment0206 medical engineeringBiomedical EngineeringIngenieurwissenschaften [620]02 engineering and technologyBone tissueBone morphogenetic proteinchemistry.chemical_compoundPolymer chemistrymedicineGeneral Materials ScienceBone regenerationGrowth factorBiomaterialPullulanGeneral ChemistryGeneral Medicine021001 nanoscience & nanotechnology020601 biomedical engineering620620: Ingenieurwissenschaftenmedicine.anatomical_structurechemistrySelf-healing hydrogelsBiophysicsddc:6200210 nano-technology
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