Search results for "Partial"

showing 10 items of 1477 documents

Analysis of a Parabolic Cross-Diffusion Semiconductor Model with Electron-Hole Scattering

2007

The global-in-time existence of non-negative solutions to a parabolic strongly coupled system with mixed Dirichlet–Neumann boundary conditions is shown. The system describes the time evolution of the electron and hole densities in a semiconductor when electron-hole scattering is taken into account. The parabolic equations are coupled to the Poisson equation for the electrostatic potential. Written in the quasi-Fermi potential variables, the diffusion matrix of the parabolic system contains strong cross-diffusion terms and is only positive semi-definite such that the problem is formally of degenerate type. The existence proof is based on the study of a fully discretized version of the system…

Parabolic cylindrical coordinatesApplied MathematicsDegenerate energy levelsMathematical analysisBoundary value problemParabolic cylinder functionPoisson's equationGalerkin methodParabolic partial differential equationBackward Euler methodAnalysisMathematicsCommunications in Partial Differential Equations
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On One Identification Problem in Linear Elasticity

1990

In practice we meet problems, when having the solution of partial differential equation, we want to discover parts in the domain of its definition where the solution has some specific properties. In [1] and [2] the problem of identification of a curve φ, lying inside of Ω such that the flux \(\int{_{\varphi }}\frac{\partial u}{\partial n}ds\) is maximal has been studied, where u is the solution of mixed—boundary value problem for Laplacian operator.

Parameter identification problemPhysicsPure mathematicsPartial differential equationLinear elasticityLaplace operatorDomain (mathematical analysis)
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C*-seminorms generated by families of biweights on partial *-algebras

2011

If A[t] is a topological partial *-algebra with unit, topologized by the family of seminorms {p_a}, the notion of bounded element is defined, and some conditions to obtain an unbounded C*-seminorm q(x)=sup p_a(x) on A[t] with domain the subalgebra of bounded elements of A[t] are given.

Partial *-algebra C*-seminorms bounded elementSettore MAT/05 - Analisi Matematica
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Block partial directed coherence: a new tool for the structural analysis of brain Networks

2012

Partial Directed Coherence Multivariate Analysis
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Element-Specific Magnetic and Electronic Properties of Epitaxial Heusler Films

2015

X-ray magnetic circular dichroism (XMCD) provides an experimental access to element-specific electronic properties of thin epitaxial films of Heusler alloys. The combination of bulk-sensitive transmission and surface-sensitive electron yield methods reveals quantitative information on bulk and interface properties. Extreme cases of magnetically dead and life layers at interfaces illustrate the high potential of XMCD. The dependence of XMCD on disorder, structure and composition is discussed as well as dynamic properties investigated by a combination of ferromagnetic resonance and XMCD. Examples are shown where spectroscopic information provided by XMCD is exploited to discuss subtle changes…

Partial density of statesCondensed Matter::Materials ScienceMagnetizationMaterials scienceCondensed matter physicsMagnetic circular dichroismElectron yieldengineeringengineering.materialEpitaxyHeusler compoundFerromagnetic resonanceElectronic properties
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Existence and uniqueness for the Prandtl equations

2001

International audience; Under the hypothesis of analyticity of the data with respect to the tangential variable we prove the existence and uniqueness of the mild solution of Prandtl boundary layer equation. This can be considered an improvement of the results of [8] as we do not require analyticity with respect to the normal variable. (C) 2001 Academie des sciences/Editions scientifiques et medicales Elsevier SAS.

Partial differential equation010102 general mathematicsPrandtl numberMathematical analysisGeneral Medicine01 natural sciencesEuler equations010101 applied mathematicssymbols.namesakeBoundary layer[MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph]symbolsUniqueness0101 mathematicsConvection–diffusion equationNavier–Stokes equationsVariable (mathematics)Mathematics
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Quasi-linear diffusion equations with gradient terms and L1 data

2004

Abstract In this article we study the following quasi-linear parabolic problem: u t − Δ u+|u| β−2 u| ∇ u| q =|u| α−2 u| ∇ u| p in Ω×]0,T[, u(x,t)=0 on ∂Ω×]0,T[, u(x,0)=u 0 (x) in Ω, where Ω is a bounded open set of R N and T>0. We prove that if α,β>1, 0⩽p u 0 ∈L 1 (Ω) .

Partial differential equationApplied MathematicsBounded functionMathematical analysisOpen setParabolic problemQuasi linearDiffusion (business)AnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
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Formation of Coherent Structures in Kolmogorov Flow with Stratification and Drag

2014

We study a weakly stratified Kolmogorov flow under the effect of a small linear drag. We perform a linear stability analysis of the basic state. We construct the finite dimensional dynamical system deriving from the truncated Fourier mode approximation. Using the Reynolds number as bifurcation parameter we build the corresponding diagram up to Re=100. We observe the coexistence of three coherent structures.

Partial differential equationApplied MathematicsDiagramMathematical analysisReynolds numberDynamical systemPhysics::Fluid DynamicsLinear stability analysisymbols.namesakeFourier transformBifurcation theoryDragsymbolsBifurcation theoryEquilibriaTruncated Navier-Stokes equationsSettore MAT/07 - Fisica MatematicaBifurcationMathematics
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Singular integrals, analytic capacity and rectifiability

1997

In this survey we study some interplay between classical complex analysis (removable sets for bounded analytic functions), harmonic analysis (singular integrals), and geometric measure theory (rectifiability).

Partial differential equationApplied MathematicsGeneral MathematicsMathematical analysisSingular integralGeometric measure theorysymbols.namesakeSingular solutionFourier analysisBounded functionsymbolsAnalytic capacityAnalysisMathematicsAnalytic functionThe Journal of Fourier Analysis and Applications
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A free boundary problem stemmed from combustion theory. Part II: Stability, instability and bifurcation results

2002

AbstractWe deal with a free boundary problem, depending on a real parameter λ, in a infinite strip in R2, providing stability, instability and bifurcation.

Partial differential equationApplied MathematicsMathematical analysisLinearizationSaddle-node bifurcationFully nonlinear elliptic and parabolic systemsBifurcation diagramFree boundary problemsInstabilityTranscritical bifurcationLinearizationFree boundary problemBifurcationStabilityBifurcationAnalysisMathematicsJournal of Mathematical Analysis and Applications
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