Search results for "Nonlinearity."

showing 10 items of 41 documents

Dependence of Perceived Purity of a Chromatic Stimulus on Saturation Adaptation

2012

Background and Objective. The purpose of sensory adaptation of the visual system is to adjust sensitivity of the photoreceptors to optimize the dynamic range of response of the visual system. It has been shown in numerous research papers that chromatic adaptation influences both color appearance and color discrimination. However, there are almost no studies in which the influence of chromatic adaptation on perceived purity has been investigated. Therefore, the aim of this study was to investigate how chromatic adaptation to stimuli with certain saturation influences perceived purity of test stimuli with the same hue but different saturation. Material and Methods. As the stimuli were modulat…

AdultMaleSensory Adaptationgenetic structuresAdaptation Ocularbusiness.industrychromatic adaptation; color saturation; color purity; perceptual nonlinearityColorGeneral MedicineMiddle AgedStimulus (physiology)Young AdultChromatic adaptationColor purityPsychophysicsHumansMedicineFemaleChromatic scaleAbney effectBiological systembusinessColor PerceptionPhotic StimulationHueMedicina; Volume 48; Issue 9; Pages: 68
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FROM DISCRETE KINETIC AND STOCHASTIC GAME THEORY TO MODELLING COMPLEX SYSTEMS IN APPLIED SCIENCES

2004

This paper deals with some methodological aspects related to the discretization of a class of integro-differential equations modelling the evolution of the probability distribution over the microscopic state of a large system of interacting individuals. The microscopic state includes both mechanical and socio-biological variables. The discretization of the microscopic state generates a class of dynamical systems defining the evolution of the densities of the discretized state. In general, this yields a system of partial differential equations replacing the continuous integro-differential equation. As an example, a specific application is discussed, which refers to modelling in the field of…

Class (set theory)Partial differential equationDiscretizationField (physics)Dynamical systems theoryApplied Mathematicspopulation modelsMathematical analysisStochastic gameBoltzmann modelsComplex systemnonlinearityModeling and SimulationApplied mathematicsProbability distributiondiscretizationKinetic theoryMathematicsMathematical Models and Methods in Applied Sciences
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Dynamics of thermally induced optical nonlinearity in GaSe thin slabs

1996

A study of the nonlinear effects shown by thin slabs of GaSe metaled with Au is presented.

Condensed Matter::Quantum Gasesendocrine systemanimal structuresMaterials sciencegenetic structuresbusiness.industryDynamics (mechanics)Physics::OpticsFísicaNonlinear opticsCondensed Matter Physicseye diseasesAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic MaterialsPhysics::Fluid DynamicsCondensed Matter::Soft Condensed MatterOptical nonlinearityOpticsPhysics::Plasma Physicssense organsElectrical and Electronic EngineeringbusinessMicrowave and Optical Technology Letters
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(p, 2)-Equations with a Crossing Nonlinearity and Concave Terms

2018

We consider a parametric Dirichlet problem driven by the sum of a p-Laplacian ($$p>2$$) and a Laplacian (a (p, 2)-equation). The reaction consists of an asymmetric $$(p-1)$$-linear term which is resonant as $$x \rightarrow - \infty $$, plus a concave term. However, in this case the concave term enters with a negative sign. Using variational tools together with suitable truncation techniques and Morse theory (critical groups), we show that when the parameter is small the problem has at least three nontrivial smooth solutions.

Dirichlet problem0209 industrial biotechnologyControl and OptimizationMultiple smooth solutionTruncationConcave termApplied Mathematicsp-Laplacian010102 general mathematicsMathematical analysis02 engineering and technology01 natural sciencesTerm (time)Nonlinear system020901 industrial engineering & automationSettore MAT/05 - Analisi MatematicaCrossing nonlinearityNonlinear maximum principle0101 mathematicsLaplace operatorCritical groupNonlinear regularityMorse theoryParametric statisticsMathematicsApplied Mathematics & Optimization
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Multiple solutions for a Dirichlet problem with p-Laplacian and set-valued nonlinearity

2008

AbstractThe existence of a negative solution, of a positive solution, and of a sign-changing solution to a Dirichlet eigenvalue problem with p-Laplacian and multi-valued nonlinearity is investigated via sub- and supersolution methods as well as variational techniques for nonsmooth functions.

Dirichlet problemGeneral MathematicsMathematical analysisNull (mathematics)Multiple solutions Dirichlet problem p-Laplacian set-valued nonlinearitySet (abstract data type)symbols.namesakeGeneralized gradientNonlinear systemDirichlet eigenvalueSettore MAT/05 - Analisi MatematicaDirichlet's principlep-LaplaciansymbolsMathematics
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Bounded weak solutions to superlinear Dirichlet double phase problems

2023

AbstractIn this paper we study a Dirichlet double phase problem with a parametric superlinear right-hand side that has subcritical growth. Under very general assumptions on the data, we prove the existence of at least two nontrivial bounded weak solutions to such problem by using variational methods and critical point theory. In contrast to other works we do not need to suppose the Ambrosetti–Rabinowitz condition.

Double phase operatorAlgebra and Number TheorySettore MAT/05 - Analisi MatematicaCritical point theorySuperlinear nonlinearityLocation of the solutionsMathematical PhysicsAnalysisParametric problem
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Nonlinearity in intergenerational income transmission: A cross-country analysis

2016

Abstract The aim of this paper is to explore nonlinearity in intergenerational income transmission. We use a set of occupational tables in different countries to test nonlinearity. We also empirically address how policy variables can affect nonlinearity. Our findings suggest that concavity is supported in those societies with less credit constraints, but with more poverty and income inequality; education has an increasing effect on convexity.

Economics and EconometricsEconomics Econometrics and Finance (miscellaneous)Affect (psychology)Convexitylaw.inventionEducationEconomic inequalitylaw0502 economics and business050602 political science & public administrationEconometricsEconomics050207 economicsIncome inequalitySet (psychology)Credit constraintCross country analysisPublic economicsPoverty05 social sciencesComputer Science::Computers and Society0506 political scienceNonlinear systemBecker–Tomes modelTransmission (mechanics)Settore SECS-P/03 - Scienza Delle FinanzeNonlinearity.
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Finance, globalisation, technology and inequality: Do nonlinearities matter?

2021

Abstract Relying on data for 90 economies over 1970-2015 and panel estimation techniques, we investigate how financial development, globalisation and technology affect income inequality. Our findings reveal significant nonlinearities, consistent with either Ushaped or inverted-U shaped relationships. As such, depending on whether a certain threshold value is achieved, the same determinants of income distribution exert opposite effects in different countries. Globalisation is associated with increasing inequality in most advanced economies, but with falling disparities for the large majority of emerging economies. Technology and financial development lead to increasing inequality for most em…

Economics and EconometricsTransmission channelLabour economicsTechnology050208 financeInequalitymedia_common.quotation_subject05 social sciencesForeign direct investmentGlobalizationEconomic inequalityInequalityIncome distribution0502 economics and businessEconomics050207 economicsEmerging marketsGlobalizationNonlinearityFinancePanel datamedia_commonPanel data
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No linealidad y asimetría en el proceso generador del Índice Ibex35

2013

This paper analyzes the behavior of Ibex35 from January 1999 to December 2001, in order to check if it follows a different process from random walk so its return is not a white noise and it can be predictable, against the efficient market hypothesis. For that, a nonlinear generating process of return will be considered and a STAR-APARCH model will be specified. This model allows a nonlinear behavior in the conditional mean and in the conditional variance. The empirical results show that the Ibex35 follows a nonlinear and asymmetric process, both in the conditional mean as in the conditional variance, so the weak-version of efficient market hypothesis is rejected. El trabajo analiza el compo…

Economics and Econometricsjel:C53White noisejel:C22EconomiaConditional expectationRandom walkEfficient-market hypothesisNonlinear systemjel:G14Order (exchange)Mercados eficientes no linealidad asimetría media condicional varianza condicional modelos autorregresivos con umbral Efficient markets nonlinearity asymmetry conditional mean conditional variance threshold autoregressive modelsStatisticsEconometricsConditional varianceMathematics
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Least energy solutions to the Dirichlet problem for the equation −D(u) = f (x, u)

2017

Let be a bounded smooth domain in RN. We prove a general existence result of least energy solutions and least energy nodal ones for the problem −u = f(x, u) in u = 0 on ∂ (P) where f is a Carathéodory function. Our result includes some previous results related to special cases of f . Finally, we propose some open questions concerning the global minima of the restriction on the Nehari manifold of the energy functional associated with (P) when the nonlinearity is of the type f(x, u) = λ|u| s−2u − μ|u| r−2u, with s, r ∈ (1, 2) and λ,μ > 0.

Elliptic problemNehari manifoldnodal solutionsublinear nonlinearity01 natural sciencesvariational methodDomain (mathematical analysis)010305 fluids & plasmasSettore MAT/05 - Analisi Matematica0103 physical sciences0101 mathematicsNehari manifoldEnergy functionalMathematicsleast energyDirichlet problemNumerical AnalysisApplied MathematicsWeak solution010102 general mathematicsMathematical analysisweak solutionFunction (mathematics)Maxima and minimaComputational MathematicsBounded functionAnalysis
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