Search results for "fer"

showing 10 items of 33109 documents

Stochastic Response on Non-Linear Systems under Parametric Non-Gaussian Agencies

1992

The probabilistic response characterization of non-linear systems subjected to non-normal delta correlated parametric excitation is obtained. In order to do this an extension of both Ito’s differential rule and the Fokker-Planck equation is presented, enabling one to account for the effect of the non-normal input. The validity of the approach reported here is confirmed by results obtained by means of a Monte Carlo simulation.

symbols.namesakeNonlinear systemGaussianMonte Carlo methodStatisticsProbabilistic logicsymbolsApplied mathematicsExtension (predicate logic)Differential (infinitesimal)ExcitationMathematicsParametric statistics
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Modal analysis for random response of MDOF systems

1990

The usefulness of the mode-superposition method of multidegrees of freedom systems excited by stochastic vector processes is here presented. The differential equations of moments of every order are written in compact form by means of the Kronecker algebra; then the method for integration of these equations is presented for both classically and non-classically damped systems, showing that the fundamental operator available for evaluating the response in the deterministic analysis is also useful for evaluating the response in the stochastic analysis.

symbols.namesakeOperator (computer programming)Computer scienceDifferential equationStochastic processModal analysisKronecker deltaRandom responsesymbolsOrder (ring theory)Applied mathematicsProbability vector
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Stealth dicing with Bessel beams and beyond

2016

In the context of laser cutting of transparent materials, we investigate glass cleaving with Bessel beams and report that a modification of the beam with 3 main lobes drastically enhances cleavability and reduces defects.

symbols.namesakeOpticsMaterials processingMaterials sciencebusiness.industryLaser cuttingsymbolsBeam shapingWafer dicingContext (language use)businessBessel functionBeam (structure)Lasers Congress 2016 (ASSL, LSC, LAC)
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Itô-Stratonovitch Formula for the Wave Equation on a Torus

2010

We give an Ito-Stratonovitch formula for the wave equation on a torus, where we have no stochastic process associated to this partial differential equation. This gives a generalization of the classical Ito-Stratonovitch equation for diffusion in semi-group theory established by ourself in [18], [20].

symbols.namesakePartial differential equationDiffusion equationMathematics::ProbabilityDifferential equationMathematical analysisFirst-order partial differential equationsymbolsFokker–Planck equationFisher's equationWave equationd'Alembert's formulaMathematics
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Random Walk and Diffusion

2014

The concept of random walk as introduced by Einstein is introduced. It is shown that a random walk on a lattice can be descrbed by a difference equation, which becomes a partial differential equation (diffusion equation) in the continuum limit. The equation is solved with the help of Fourier and Laplace transformations.

symbols.namesakePartial differential equationHeterogeneous random walk in one dimensionDiffusion equationFourier transformLaplace transformDifferential equationMathematical analysissymbolsEinsteinRandom walkMathematics
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Second harmonic ac polarography of strongly adsorbed electroactive species

1981

Abstract The second harmonic ac current is calculated for the case of a quasi-reversible surface redox system: both species are strongly adsorbed according to a Langmuir isotherm and the kinetics of the process are controlled by the electron transfer. The current is measured with a phase-sensitive detector and the variation of the in-phase and quadrature components vs. the frequency leads to the surface rate constant ks. The experimental results obtained for benzo-(c)cinnoline are in good agreement with the theoretical predictions and with the results of impedance measurements. The advantages of the two methods are compared.

symbols.namesakePolarographyElectron transferReaction rate constantAdsorptionChemistryKineticssymbolsAnalytical chemistryLangmuir adsorption modelRedoxElectrical impedanceJournal of Electroanalytical Chemistry and Interfacial Electrochemistry
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Explicit expressions for Sturm-Liouville operator problems

1987

Throughout this paper H will denote a complex separable Hilbert space and L(H) denotes the algebra of all bounded linear operators on H. If T lies in L(H), its spectrum σ(T) is the set of all complex numbers z such zI–T is not invertible in L(H) and its compression spectrum σcomp(T) is the set of all complex numbers z such that the range (zI-T)(H) is not dense in H ([3, p. 240]). This paper is concerned with the Sturm–Liouville operator problemwhere λ is a complex parameter and X(t), Q, Ei, Fi for i = l,2, and t∈[0,a], are bounded operators in L(H). For the scalar case, the classical Sturm-Liouville theory yields a complete solution of the problem, see [4], and [7]. For the finite-dimension…

symbols.namesakePure mathematicsDifferential equationGeneral MathematicsOperator (physics)Mathematical analysisHilbert spacesymbolsSturm–Liouville theoryMathematicsProceedings of the Edinburgh Mathematical Society
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Mappings of finite distortion: Reverse inequalities for the Jacobian

2007

Let f be a nonconstant mapping of finite distortion. We establish integrability results on 1/Jf by studying weights that satisfy a weak reverse Holder inequality where the associated constant can depend on the ball in question. Here Jf is the Jacobian determinant of f.

symbols.namesakePure mathematicsDifferential geometryFourier analysisMathematical analysisJacobian matrix and determinantsymbolsGeometry and TopologyBall (mathematics)Reverse holder inequalityMathematicsJournal of Geometric Analysis
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Distribution of Large Eigenvalues for Elliptic Operators

2019

In this chapter we consider elliptic differential operators on a compact manifold and rather than taking the semi-classical limit (h →), we let h = 1 and study the distribution of large eigenvalues. Bordeaux Montrieux (Loi de Weyl presque sure et resolvante pour des operateurs differentiels non-autoadjoints, these, CMLS, Ecole Polytechnique, 2008. https://pastel.archives-ouvertes.fr/pastel-00005367, Ann Henri Poincare 12:173–204, 2011) studied elliptic systems of differential operators on S1 with random perturbations of the coefficients, and under some additional assumptions, he showed that the large eigenvalues obey the Weyl law almost surely. His analysis was based on a reduction to the s…

symbols.namesakePure mathematicsElliptic operatorDistribution (mathematics)Weyl lawPoincaré conjecturesymbolsAlmost surelyDifferential operatorEigenvalues and eigenvectorsManifoldMathematics
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Stochastic linearization for the response of MDOF systems subjected to external and parametric Gaussian excitations

1991

The stochastic linearization approach is examined for the most general case of non zero-mean response of non-linear MDOF systems subjected to parametric and external Gaussian white excitations. It is shown that, for these systems too, stochastic linearization and Gaussian closure are two equivalent approaches if the former is applied to the coefficients of the Ito differential rule. Moreover, an extension of the Atalik-Utku approach to non zero-mean response systems allows to obtain simple formulations for the linearized drift coefficients. Some applications show the good accuracy of the method.

symbols.namesakeSimple (abstract algebra)Control theoryLinearizationGaussiansymbolsClosure (topology)Applied mathematicsRandom vibrationDifferential (infinitesimal)Parametric statisticsMathematics
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