Search results for "method."

showing 10 items of 13043 documents

$$\mathscr {K}$$-Convergence of Finite Volume Solutions of the Euler Equations

2020

We review our recent results on the convergence of invariant domain-preserving finite volume solutions to the Euler equations of gas dynamics. If the classical solution exists we obtain strong convergence of numerical solutions to the classical one applying the weak-strong uniqueness principle. On the other hand, if the classical solution does not exist we adapt the well-known Prokhorov compactness theorem to space-time probability measures that are generated by the sequences of finite volume solutions and show how to obtain the strong convergence in space and time of observable quantities. This can be achieved even in the case of ill-posed Euler equations having possibly many oscillatory s…

symbols.namesakeFinite volume methodSpacetimeCompactness theoremsymbolsApplied mathematicsObservableUniquenessInvariant (physics)Euler equationsMathematicsProbability measure
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An explicit unconditionally stable numerical solution of the advection problem in irrotational flow fields

2004

[1] A new methodology for the Eulerian numerical solution of the advection problem is proposed. The methodology is based on the conservation of both the zero- and the first-order spatial moments inside each element of the computational domain and leads to the solution of several small systems of ordinary differential equations. Since the systems are solved sequentially (one element after the other), the method can be classified as explicit. The proposed methodology has the following properties: (1) it guarantees local and global mass conservation, (2) it is unconditionally stable, and (3) it applies second-order approximation of the concentration and its fluxes inside each element. Limitati…

symbols.namesakeFlow (mathematics)AdvectionOrdinary differential equationMathematical analysisVolume of fluid methodsymbolsEulerian pathConservative vector fieldConservation of massDomain (mathematical analysis)Water Science and TechnologyMathematicsWater Resources Research
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The Radon-Wigner Transform and Its Application to First-order Optical Systems

2009

The Radon-Wigner transform is presented as a tool for the description of 1st-order optical systems. The input/output relationships for this phase-space representation are obtained and their application in analysis and design tasks is pointed out.

symbols.namesakeFourier transformComputer scienceHartley transformComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISIONsymbolsShort-time Fourier transformHarmonic wavelet transformS transformAlgorithmConstant Q transformDiscrete Fourier transformFractional Fourier transformFrontiers in Optics 2009/Laser Science XXV/Fall 2009 OSA Optics & Photonics Technical Digest
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A Stieltjes Approach to Static Hedges

2014

Static hedging of complicated payoff structures by standard instruments becomes increasingly popular in finance. The classical approach is developed for quite regular functions, while for less regular cases, generalized functions and approximation arguments are used. In this note, we discuss the regularity conditions in the classical decomposition formula due to P. Carr and D. Madan (in Jarrow ed, Volatility, pp. 417–427, Risk Publ., London, 1998) if the integrals in this formula are interpreted as Lebesgue integrals with respect to the Lebesgue measure. Furthermore, we show that if we replace these integrals by Lebesgue–Stieltjes integrals, the family of representable functions can be exte…

symbols.namesakeGeneralized functionLebesgue measureDirect methodMathematical analysisBounded variationStochastic gamesymbolsApplied mathematicsRiemann–Stieltjes integralAbsolute continuityLebesgue integrationMathematics
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Jacobi Fields, Conjugate Points

2001

Let us go back to the action principle as realized by Jacobi, i.e., time is eliminated, so we are dealing with the space trajectory of a particle. In particular, we want to investigate the conditions under which a path is a minimum of the action and those under which it is merely an extremum. For illustrative purposes we consider a particle in two-dimensional real space.

symbols.namesakeJacobi rotationJacobi method for complex Hermitian matricesConjugate pointsPath (graph theory)TrajectorysymbolsApplied mathematicsSpace (mathematics)Action (physics)Mathematics
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Semi-discrete Galerkin approximation method applied to initial boundary value problems for Maxwell's equations in anisotropic, inhomogeneous media

1981

SynopsisIn this paper the semi-discrete Galerkin approximation of initial boundary value problems for Maxwell's equations is analysed. For the electric field a hyperbolic system of equations is first derived. The standard Galerkin method is applied to this system and a priori error estimates are established for the approximation.

symbols.namesakeMaxwell's equationsGeneral MathematicsElectric fieldMathematical analysissymbolsA priori and a posterioriBoundary value problemAnisotropyGalerkin methodHyperbolic systemsMathematicsProceedings of the Royal Society of Edinburgh: Section A Mathematics
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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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The added value of studying embodied responses in couple therapy research : A case study

2019

This article reports on the added value of embodied responses identified through sympathetic nervous system (SNS) activity in couple therapy research. It focuses on moments of change and the timing of therapeutic interventions or therapeutic moves in a couple therapy session. The data for this single‐case study comprise couple therapy process videotapes recorded in a multi‐camera setting, and measurements of participants’ SNS activity. The voluntary participants were a marital couple in their late thirties and two middle‐aged male psychotherapists. The division into topic segments showed how the key issue of seeking help, which was found to comprise three separate components, was repeatedly…

sympathetic nervous systemmixed method researchcouple therapypariterapiasympaattinen hermostoruumiillisuusembodimentdialogi
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Synchrotron x-ray transmission measurements and modeling of filters investigated for Athena

2020

International audience; Advanced Telescope for High-Energy Astrophysics is a large-class astrophysics space mission selected by the European Space Agency to study the theme "Hot and Energetic Universe." The mission essentially consists of a large effective area x-ray telescope and two detectors: the X-ray Integral Field Unit (X-IFU) and the Wide Field Imager (WFI). Both instruments require filters to shield from out-of-band radiation while providing high transparency to x-rays. The mission is presently in phase B; thus, to consolidate the preliminary design, investigated filter materials need to be properly characterized by experimental test campaigns. We report results from high-resolution…

synchrotron radiationComputer scienceAstrophysics::High Energy Astrophysical PhenomenaMechanical EngineeringAstrophysics::Instrumentation and Methods for AstrophysicsSynchrotron radiationtelescopesAstronomy and AstrophysicsElectronic Optical and Magnetic Materialslaw.inventionTelescopeFilter designSettore FIS/05 - Astronomia E AstrofisicaTransmission (telecommunications)Space and Planetary ScienceControl and Systems EngineeringlawFilter (video)[SDU]Sciences of the Universe [physics]CalibrationOptical filterInstrumentationDigital filterastrophysics space mission Athena optical and thermal filters Wide Field Imager X-ray Integral Field Unit x-ray transmissionRemote sensing
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From “Strategic Fit” to Synergy Evaluation in M&A Deals

2012

The aim of this paper is to grasp the processes underlying the genesis and assessment of synergies in M&A deals. We proceed to an in-depth scrutiny of the foundations of synergies using Porter’s model of the value chain. A discernment of the nature of synergies and the mode of their emergence is helpful to clarify to what extent and under which boundary conditions it is appropriate to apply the DCF or the real option techniques for evaluating each type of synergy. Combining both financial tools, the methodology suggested for evaluating the synergies is able to: evaluate projects of M&As, orient the selection of target firms and the definition of the premium of acquisition, and drive…

synergy M&ampmerger; acquisition; synergy; Porter’s value chain; evaluationevaluationA evaluation methodmerger; acquisition; synergy; Porter’s value chain; evaluation;acquisitionsynergySettore SECS-P/08 - Economia e Gestione delle ImpresePorter’s value chainmerger
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