Search results for "Linea"

showing 10 items of 7724 documents

Weak commutation relations of unbounded operators and applications

2011

Four possible definitions of the commutation relation $[S,T]=\Id$ of two closable unbounded operators $S,T$ are compared. The {\em weak} sense of this commutator is given in terms of the inner product of the Hilbert space $\H$ where the operators act. Some consequences on the existence of eigenvectors of two number-like operators are derived and the partial O*-algebra generated by $S,T$ is studied. Some applications are also considered.

CommutatorPure mathematicsunbounded operatorsCommutation relationHilbert spaceMathematics - Operator AlgebrasFOS: Physical sciencesStatistical and Nonlinear PhysicsMathematical Physics (math-ph)symbols.namesakeSettore MAT/05 - Analisi MatematicaProduct (mathematics)Linear algebraFOS: MathematicssymbolsCommutationOperator Algebras (math.OA)Settore MAT/07 - Fisica MatematicaEigenvalues and eigenvectorsMathematical PhysicsMathematics
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Asymptotic behaviors of solutions to quasilinear elliptic equations with Hardy potential

2016

Optimal estimates on asymptotic behaviors of weak solutions both at the origin and at the infinity are obtained to the following quasilinear elliptic equations

Comparison principleApplied Mathematicsmedia_common.quotation_subjectta111010102 general mathematicsMathematical analysisMathematics::Analysis of PDEsHardy's inequalityInfinity01 natural sciences010101 applied mathematicsQuasilinear elliptic equations0101 mathematicsAsymptotic behaviorsHardy's inequalityAnalysisMathematicsmedia_commonJournal of Mathematical Analysis and Applications
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Asymptotic behaviors of solutions to quasilinear elliptic equations with Hardy potential

2016

Optimal estimates on asymptotic behaviors of weak solutions both at the origin and at the infinity are obtained to the following quasilinear elliptic equations −Δpu − μ |x| p |u| p−2 u + m|u| p−2 u = f(u), x ∈ RN , where 1 0 and f is a continuous function. peerReviewed

Comparison principleQuasilinear elliptic equationsHardy's inequalityAsymptotic behaviors
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Nonlinear Nonhomogeneous Robin Problems with Almost Critical and Partially Concave Reaction

2020

We consider a nonlinear Robin problem driven by a nonhomogeneous differential operator, with reaction which exhibits the competition of two Caratheodory terms. One is parametric, $$(p-1)$$-sublinear with a partially concave nonlinearity near zero. The other is $$(p-1)$$-superlinear and has almost critical growth. Exploiting the special geometry of the problem, we prove a bifurcation-type result, describing the changes in the set of positive solutions as the parameter $$\lambda >0$$ varies.

Competition phenomenacompetition phenomenanonlinear maximum principleAlmost critical growthLambda01 natural sciencesSet (abstract data type)symbols.namesakeMathematics - Analysis of PDEsSettore MAT/05 - Analisi Matematica0103 physical sciencesFOS: Mathematics0101 mathematicsbifurcation-type resultMathematicsParametric statisticsNonlinear regularity35J20 35J60010102 general mathematicsMathematical analysisZero (complex analysis)udc:517.956.2Differential operatorBifurcation-type resultalmost critical growthNonlinear systemDifferential geometryFourier analysissymbolsnonlinear regularity010307 mathematical physicsGeometry and TopologyNonlinear maximum principleStrong comparison principlestrong comparison principleAnalysis of PDEs (math.AP)
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Tactical metrics that discriminate winning, drawing and losing teams in UEFA Euro 2012®

2015

The objectives of this article are twofold: first, an innovative approach to notational analysis in football is outlined. By considering the important theoretical requirements for the analysis of sports games (like the interaction between two parties, the procedural sequence of action or the significance of tactical behaviour) the meaning of the introduced parameters, called tactical metrics, is illustrated. In a second step, the validity of this approach is tested using matches of the Union of European Football Associations (UEFA) Euro 2012® to investigate a connection between these metrics and success. The results show that 11 tactical metrics model tactical behaviour in 4 different dimen…

Competitive BehaviorOperations researchComputer scienceDiscriminant AnalysisPhysical Therapy Sports Therapy and Rehabilitation030229 sport sciencesFootballAthletic PerformanceLinear discriminant analysisEurope03 medical and health sciences0302 clinical medicineMotor SkillsSoccerTask Performance and AnalysisBall (bearing)HumansNotational analysisOrthopedics and Sports Medicine030217 neurology & neurosurgeryJournal of Sports Sciences
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Digital information receiver based on stochastic resonance

2003

International audience; An electronic receiver based on stochastic resonance is presented to rescue subthreshold modulated digital data. In real experiment, it is shown that a complete data restoration is achieved for both uniform and Gaussian white noise.

Complete data[ INFO.INFO-TS ] Computer Science [cs]/Signal and Image ProcessingComputer scienceStochastic resonance[ PHYS.COND.CM-DS-NN ] Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn]Digital dataNonlinear signal processing[ SPI.SIGNAL ] Engineering Sciences [physics]/Signal and Image processing01 natural sciences010305 fluids & plasmas[NLIN.NLIN-PS]Nonlinear Sciences [physics]/Pattern Formation and Solitons [nlin.PS][INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing0103 physical sciencesElectronic engineering[ NLIN.NLIN-PS ] Nonlinear Sciences [physics]/Pattern Formation and Solitons [nlin.PS][PHYS.COND.CM-DS-NN]Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn]stochastic resonance010306 general physicsEngineering (miscellaneous)Subthreshold conductionbusiness.industryApplied MathematicsWhite noise[SPI.TRON]Engineering Sciences [physics]/Electronics[ SPI.TRON ] Engineering Sciences [physics]/ElectronicsNonlinear systemModeling and SimulationNonlinear dynamicsTelecommunicationsbusiness[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
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Thermal solitons in nanotubes

2022

Starting from a recent proposal of a nonlinear Maxwell-Cattaneo equation for the heat transport with relaxational effects at nanoscale, in a special case of thermal-wave propagation we derive a nonlinear Schrodinger equation for the amplitudes of the heatflux perturbation. The complete integrability of the obtained equation is investigated in order to prove the existence of infinite conservation laws, as well as the existence of infinite exact solutions. In this regards, we have considered the simplest nontrivial solutions, namely, the bright and dark (thermal) solitons, which may be interesting for energy transport and for information transmission in phononic circuits. (c) 2022 Elsevier B.…

Complete integrabilityComputational MathematicsThermal solitonsApplied MathematicsModeling and SimulationComplete integrability; Extended Non-Equilibrium Thermodynamics; Maxwell–Cattaneo law; Nonlinear Schrödinger equation; Thermal solitonsNonlinear Schrödinger equationGeneral Physics and AstronomyNonlinear Schroedinger equation Thermal solitons Maxwell-Cattaneo law Extended Non-Equilibrium Thermodynamics Complete integrabilityMaxwell–Cattaneo lawSettore MAT/07 - Fisica MatematicaExtended Non-Equilibrium Thermodynamics
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A Lebesgue-type decomposition for non-positive sesquilinear forms

2018

A Lebesgue-type decomposition of a (non necessarily non-negative) sesquilinear form with respect to a non-negative one is studied. This decomposition consists of a sum of three parts: two are dominated by an absolutely continuous form and a singular non-negative one, respectively, and the latter is majorized by the product of an absolutely continuous and a singular non-negative forms. The Lebesgue decomposition of a complex measure is given as application.

Complex measurePure mathematicsSesquilinear formType (model theory)Lebesgue integration01 natural sciencesRegularitysymbols.namesakeSettore MAT/05 - Analisi MatematicaLebesgue decomposition0103 physical sciencesDecomposition (computer science)Complex measureFOS: Mathematics0101 mathematicsMathematicsMathematics::Functional AnalysisSingularitySesquilinear formApplied Mathematics010102 general mathematicsAbsolute continuityFunctional Analysis (math.FA)Mathematics - Functional Analysis47A07 15A63 28A12 47A12Product (mathematics)symbols010307 mathematical physicsNumerical range
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Extension of The Stochastic Differential Calculus To Complex Processes

1996

In structural engineering complex processes arise to predict the first excursion failure, fatigue failure, etc. Indeed to solve these problems the envelope function, which is the modulus of a complex process, is usually introduced. In this paper the statistics of the complex response process related to the envelope statistics of linear systems subjected to parametric stationary normal white noise input are evaluated by using extensively the properties of stochastic differential calculus.

Complex responseProcess (engineering)Multivariable calculusExcursionLinear systemMathematical analysisApplied mathematicsDifferential calculusWhite noiseMathematicsParametric statistics
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Singularity formation for Prandtl’s equations

2009

Abstract We consider Prandtl’s equations for an impulsively started disk and follow the process of the formation of the singularity in the complex plane using the singularity tracking method. We classify Van Dommelen and Shen’s singularity as a cubic root singularity. We introduce a class of initial data, uniformly bounded in H 1 , which have a dipole singularity in the complex plane. These data lead to a solution blow-up whose time can be made arbitrarily short within the class. This is numerical evidence of the ill-posedness of the Prandtl equations in H 1 . The presence of a small viscosity in the streamwise direction changes the behavior of the singularities. They stabilize at a distanc…

Complex singularitiePrandtl numberFOS: Physical sciencesRegularizing viscositySeparationPhysics::Fluid Dynamicssymbols.namesakeViscosityMathematics - Analysis of PDEsSingularityFOS: MathematicsUniform boundednessSpectral methodSettore MAT/07 - Fisica MatematicaMathematical PhysicsMathematicsMathematical analysisStatistical and Nonlinear PhysicsMathematical Physics (math-ph)Condensed Matter PhysicsPrandtl–Glauert transformationPrandtl’s equationsymbolsGravitational singularitySpectral methodComplex planeAnalysis of PDEs (math.AP)Blow–up timePhysica D: Nonlinear Phenomena
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