Search results for "Bounded"

showing 10 items of 658 documents

Quasi-linear parabolic equations with degenerate coercivity having a quadratic gradient term

2006

We study existence and regularity of distributional solutions for possibly degenerate quasi-linear parabolic problems having a first order term which grows quadratically in the gradient. The model problem we refer to is the following (1){ut−div(α(u)∇u)=β(u)|∇u|2+f(x,t),in Ω×]0,T[;u(x,t)=0,on ∂Ω×]0,T[;u(x,0)=u0(x),in Ω. Here Ω is a bounded open set in RN, T>0. The unknown function u=u(x,t) depends on x∈Ω and t∈]0,T[. The symbol ∇u denotes the gradient of u with respect to x. The real functions α, β are continuous; moreover α is positive, bounded and may vanish at ±∞. As far as the data are concerned, we require the following assumptions: ∫ΩΦ(u0(x))dx<∞ where Φ is a convenient function which …

Quadratic growthNonlinear parabolic problems; gradient term with quadratic growth; existence and regularity; bounded and unbounded solutions; lack of coercivenesstermine quadratico nel gradienteApplied MathematicsOperator (physics)existence and regularityMathematical analysisDegenerate energy levelsFunction (mathematics)equazioni parabolichebounded and unbounded solutionsParabolic partial differential equationBounded functioncoercività degenerePrincipal partOrder (group theory)gradient term with quadratic growthNonlinear parabolic problemsMathematical PhysicsAnalysislack of coercivenessMathematics
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Quasilinear elliptic equations with singular quadratic growth terms

2011

In this paper, we deal with positive solutions for singular quasilinear problems whose model is [Formula: see text] where Ω is a bounded open set of ℝN, g ≥ 0 is a function in some Lebesgue space, and γ &gt; 0. We prove both existence and nonexistence of solutions depending on the value of γ and on the size of g.

Quadratic growthnonlinear elliptic equations; natural growth condition; vertical asymptote; measure dataApplied MathematicsGeneral MathematicsMathematical analysisOpen setmeasure dataFunction (mathematics)nonlinear elliptic equationsBounded functionvertical asymptoteStandard probability spacenatural growth conditionAsymptoteValue (mathematics)Mathematics
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Journal of Economics and Management Research, Vol. 3

2014

Igo Cals. Bounded Rationality Concept and Farming Values in Latvian Agricultural Sector ; Dagnija Daņēviča, Ieva Aizsila, Roberts Ikaunieks. Audit Quality Aspects of Cooperation Between Certified Auditor and Audited Entity ; Gyula Fülöp, Bettina Hódi Hernádi. Comparison of Traditional, Environmental and Sustainability Accounting Systems ; Svetlana Jesiļevska. Similarities and Differences of Conducting Innovation Survey – Latvian and Estonian Approaches ; Silvija Kristapsone. Subjective Assessment by Teachers and Other Professionals of Well-being in Latvia in Years 2011/2012 ; Olga Rajevska. Pension Statistics in Latvia: Resources and Weaknesses ; Christin Richter. Current Developments in Ri…

Quality of lifeStakeholder managementSocial capital:SOCIAL SCIENCES::Business and economics::Economics [Research Subject Categories]Bounded rationalityInnovation statisticsExternal auditRisk cultureCitizen participationEurozonePension statisticsCorporate sustainability
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An LMI approach to quantized H&lt;inf&gt;&amp;#x221E;&lt;/inf&gt; control of uncertain linear systems with network-induced delays

2010

This paper deals with a convex optimization approach to the problem of robust network-based H ∞ control for linear systems connected over a common digital communication network with norm-bounded parameter uncertainties. Firstly, we investigate the effect of both the output quantization levels and the network conditions under static quantizers. Secondly, by introducing a descriptor technique, using Lyapunov-Krasovskii functional and a suitable change of variables, new required sufficient conditions are established in terms of delay-range-dependent linear matrix inequalities for the existence of the desired network-based quantized controllers with simultaneous consideration of network induced…

Quantization (physics)Exponential stabilityControl theoryBounded functionAttenuationConvex optimizationLinear systemRobust controlTelecommunications networkMathematics2010 Conference on Control and Fault-Tolerant Systems (SysTol)
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Adaptive Backstepping Control of Uncertain Nonlinear Systems With Input and State Quantization

2022

Though it is common in network control systems that the sensor and control signals are transmitted via a common communication network, no result is available in investigating the stabilization problem for uncertain nonlinear systems with both input and state quantization. The issue is solved in this paper, by presenting an adaptive backstepping based control algorithm for the systems with sector bounded input and state quantizers. In addition to overcome the difficulty to proceed recursive design of virtual controls with quantized states, the relation between the input signal and error state need be well established to handle the effects due to quantization. It is shown that all closed-loop…

Quantization (physics)Nonlinear systemControl and Systems EngineeringControl theoryComputer scienceBounded functionBacksteppingUniform boundednessState (functional analysis)Electrical and Electronic EngineeringTelecommunications networkSignalComputer Science ApplicationsIEEE Transactions on Automatic Control
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Representations and derivations of quasi ∗-algebras induced by local modifications of states

2009

Abstract The relationship between the GNS representations associated to states on a quasi ∗-algebra, which are local modifications of each other (in a sense which we will discuss) is examined. The role of local modifications on the spatiality of the corresponding induced derivations describing the dynamics of a given quantum system with infinite degrees of freedom is discussed.

Quasi *-algebrasPure mathematicsApplied MathematicsQuantum dynamicsDegrees of freedomAlgebras of unbounded operatorsDerivationsRepresentationSettore MAT/05 - Analisi MatematicaQuantum systemDerivationQuantum dynamicsRepresentation (mathematics)Settore MAT/07 - Fisica MatematicaAnalysisMathematicsJournal of Mathematical Analysis and Applications
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Cone conditions and quasiconformal mappings

1988

Let f be a quasiconformal mapping of the open unit ball B n = {x ∈ R n : | x | < l× in euclidean n-space R n onto a bounded domain D in that space. For dimension n= 2 the literature of geometric function theory abounds in results that correlate distinctive geometric properties of the domain D with special behavior, be it qualitative or quantitative, on the part of f or its inverse. There is a more modest, albeit growing, body of work that attempts to duplicate in dimensions three and above, where far fewer analytical tools are at a researcher’s disposal, some of the successes achieved in the plane along such lines. In this paper we contribute to that higher dimensional theory some observati…

Quasiconformal mappingPure mathematicsGeometric measure theoryGeometric function theoryBounded functionHölder conditionConformal mapBall (mathematics)Modulus of continuityMathematics
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Robin problems with general potential and double resonance

2017

Abstract We consider a semilinear elliptic problem with Robin boundary condition and an indefinite and unbounded potential. The reaction term is a Caratheodory function exhibiting linear growth near ± ∞ . We assume that double resonance occurs with respect to any positive spectral interval. Using variational tools and critical groups, we show that the problem has a nontrivial smooth solution.

Regularity theoryIndefinite and unbounded potentialApplied Mathematics010102 general mathematicsMathematical analysisInterval (mathematics)Function (mathematics)Robin boundary condition01 natural sciencesResonance (particle physics)Robin boundary conditionTerm (time)010101 applied mathematicsDouble resonance critical groupSettore MAT/05 - Analisi Matematica0101 mathematicsLinear growthMathematicsApplied Mathematics Letters
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Relaxation of certain integral functionals depending on strain and chemical composition

2012

We provide a relaxation result in $BV \times L^q$, $1\leq q &lt; +\infty$ as a first step towards the analysis of thermochemical equilibria.

RelaxationStrain (chemistry)Applied MathematicsGeneral Mathematics010102 general mathematicsMathematical analysisThermodynamics02 engineering and technologyRelaxation; functions of bounded variation; quasiconvexity.01 natural sciencesquasiconvexityMathematics - Analysis of PDEsfunctions of bounded variation0202 electrical engineering electronic engineering information engineeringFOS: MathematicsRelaxation (physics)020201 artificial intelligence & image processing0101 mathematicsPhysics::Chemical PhysicsChemical compositionMathematicsAnalysis of PDEs (math.AP)
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Remarks on Infinite-Dimensional Representations of the Heisenberg Algebra

2017

Infinite-dimensional representations of Lie algebras necessarily invoke the theory of unbounded operator algebras. Starting with the familiar example of the Heisenberg Lie algebra, we sketch the essential features of this interaction, distinguishing in particular the cases of integrable and nonintegrable representations. While integrable representations are well understood, nonintegrable representations are quite mysterious objects. We present here a short and didactical-minded overview of the subject.

RepresentationsUnbounded operatorAlgebraLie aalgebraPure mathematicsIntegrable systemSettore MAT/05 - Analisi MatematicaLie algebraSubject (philosophy)Algebra over a fieldSketchMathematics
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