Search results for "TENSOR"

showing 10 items of 550 documents

Stochastic anticipative calculus on the path space over a compact Riemannian manifold

1998

Abstract In this paper, we shall first give another expression for Cruzeiro-Malliavin structure equation, by means of the Skorohod integral. The torsion tensor with respect to the Markovian connection used in [CF] is computed. This is the key step to establish a Stroock-like formula of commutation on the derivative of the Skorohod integral, which enables us to prove an Ito formula. As an application, we shall give a maximal inequality for Skorohod integrals following [AN2].

Mathematics(all)General MathematicsApplied MathematicsMathematical analysisMarkov processDerivativeExpression (computer science)Riemannian manifoldConnection (mathematics)symbols.namesakeTorsion tensorMathematics::ProbabilitysymbolsPath spaceCommutationMathematicsJournal de Mathématiques Pures et Appliquées
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Anisotropy and symmetry for elastic properties of laminates reinforced by balanced fabrics

2001

In this article, we present a theoretical study on elastic properties of laminates composed by balanced fabric layers. Using the polar representation method for plane elastic tensors, we first describe some properties of symmetry of a general laminate composed by balanced fabrics and we write the formulas expressing positions of its axes of symmetry. Then, limiting our study to laminates composed of identical plies, we solve two problems of symmetry of the laminate elastic tensors: uncoupling and quasi-homogeneity. We found all the solutions of the uncoupling problem for the case of 3-, 4- and 5-ply laminate and all those of the quasi-homogeneity problem for the case of 4-, 5- and 6-ply lam…

Mathematics::Dynamical SystemsMaterials sciencePlane (geometry)Cauchy stress tensorMarsaglia polar methodLimitingMathematics::Geometric TopologySymmetry (physics)Mechanics of MaterialsCeramics and CompositesPolar coordinate systemComposite materialAnisotropyRepresentation (mathematics)Composites Part A: Applied Science and Manufacturing
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New results concerning Chebyshev–Grüss-type inequalities via discrete oscillations

2014

The classical form of Gruss' inequality was first published by G. Gruss and gives an estimate of the difference between the integral of the product and the product of the integrals of two functions. In the subsequent years, many variants of this inequality appeared in the literature. The aim of this paper is to consider some new bivariate Chebyshev-Gruss-type inequalities via discrete oscillations and to apply them to different tensor products of linear (not necessarily) positive, well-known operators. We also compare the new inequalities with some older results. In the end we give a Chebyshev-Gruss-type inequality with discrete oscillations for more than two functions.

Mathematics::Functional AnalysisPure mathematicsInequalityApplied Mathematicsmedia_common.quotation_subjectMathematical analysisMathematics::Classical Analysis and ODEsBivariate analysisType (model theory)Chebyshev filterComputational MathematicsTensor productProduct (mathematics)MathematikMathematicsmedia_commonApplied Mathematics and Computation
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Asplund Operators on Locally Convex Spaces

2000

We study the relationship between the local Radon-Nikodým property, introduced by Defant [4] as a generalization of the Radon-Nikodým property to duals of locally convex spaces, and the Asplund operators, introduced by Robertson [7]. We also give a characterization of Asplund symmetric tensor products of Banach spaces in terms of Asplund maps.

Mathematics::Functional AnalysisPure mathematicsProperty (philosophy)GeneralizationLocally convex topological vector spaceMathematical analysisBanach spaceAstrophysics::Solar and Stellar AstrophysicsMathematics::General TopologySymmetric tensorDual polyhedronCharacterization (mathematics)Mathematics
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Some observations on the regularizing field for gradient damage models

2000

Gradient enhanced material models can potentially preserve well-posedness of incremental boundary value problems also after the onset of strain softening. Gradient dependent constitutive relations are rooted in the assumption that some scalar or tensor field, which appears in the yield function, has to be enriched by adding a term involving its second-order gradient field. For gradient-dependent plasticity this term is universally accepted to be the equivalent plastic strain. For gradient-dependent damage models different choices have been presented in the literature. They all possess the desired regularization of the solution, but they are not identical as regards the structural response. …

Mechanical EngineeringMathematical analysisConstitutive equationComputational MechanicsDamage strain localizationPlasticityTensor fieldRegularization (physics)Solid mechanicsGradient Damage MechanicsVector fieldBoundary value problemSettore ICAR/08 - Scienza Delle CostruzioniGradient methodRegularized softeningMathematics
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Solid state NMR analysis of peptides in membranes: Influence of dynamics and labeling scheme.

2010

The functional state of a membrane-active peptide is often defined by its conformation, molecular orientation, and its oligomeric state in the lipid bilayer. These "static" structural properties can be routinely studied by solid state NMR using isotope-labeled peptides. In the highly dynamic environment of a liquid crystalline biomembrane, however, the whole-body fluctuations of a peptide are also of paramount importance, although difficult to address and most often ignored. Yet it turns out that disregarding such motional averaging in calculating the molecular alignment from orientational NMR-constraints may give a misleading, if not false picture of the system. Here, we demonstrate that t…

Models MolecularLipid BilayersBiophysicsPeptideWhole body fluctuationBiochemistryProtein Structure SecondaryOrientation (geometry)Side chainLipid bilayerNuclear Magnetic Resonance BiomolecularNMR tensor orientationchemistry.chemical_classificationChemistrySolid-state 2H- 19F- 15N-NMRPeptide orientationMembrane ProteinsBiological membraneCell BiologyGALAMembrane-bound peptidePISEMACrystallographyMembraneSolid-state nuclear magnetic resonanceChemical physicsIsotope LabelingHelixIsotope labeling schemeα-helicesPeptide dynamicPeptidesBiochimica et biophysica acta
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Diatropicity of tetraazanaphthalenes

2006

Tetraazanaphthalenes are diatropic molecules, whose magnetic response to a magnetic field perpendicular to the molecular plane closely resembles that of naphthalene. The out-of-plane component of the magnetic susceptibility tensor and its strong anisotropy can be used as quantifiers of magnetic aromaticity. Maps showing streamlines and modulus of the current density field provide clear evidence for diatropicity of these systems. They also explain the strong anisotropy of carbon and nitrogen magnetic shielding, which is determined by the big out-of-plane component of the nuclear shielding tensor. The electronic ring currents observed in the map deshield the nuclei of ring hydrogens by enforc…

Molecular StructureField (physics)ProtonCondensed matter physicsChemistryChemical shiftStereoisomerismGeneral ChemistryNaphthalenesMagnetic susceptibilityMagnetic fieldMagneticsComputational MathematicsNuclear magnetic resonanceModels ChemicalElectromagnetic shieldingAnisotropyComputer SimulationTensorAnisotropyDiatropicity; tetraazanaphthalenesJournal of Computational Chemistry
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Superfluid density and quasi-long-range order in the one-dimensional disordered Bose–Hubbard model

2015

We study the equilibrium properties of the one-dimensional disordered Bose-Hubbard model by means of a gauge-adaptive tree tensor network variational method suitable for systems with periodic boundary conditions. We compute the superfluid stiffness and superfluid correlations close to the superfluid to glass transition line, obtaining accurate locations of the critical points. By studying the statistics of the exponent of the power-law decay of the correlation, we determine the boundary between the superfluid region and the Bose glass phase in the regime of strong disorder and in the weakly interacting region, not explored numerically before. In the former case our simulations are in agreem…

Monte Carlo methodGeneral Physics and AstronomyBoundary (topology)FOS: Physical sciencesBose–Hubbard model01 natural sciencesCondensed Matter::Disordered Systems and Neural Networks010305 fluids & plasmasSuperfluidityPhysics and Astronomy (all)Bose glass; disorder-driven phase transition; numerical simulation of quantum many-body systems; Physics and Astronomy (all)0103 physical sciencesnumerical simulation of quantum many-body systemsPeriodic boundary conditionsTensor010306 general physicsPhysicsCondensed Matter::Quantum GasesQuantum PhysicsCondensed matter physicsdisorder-driven phase transitionCondensed Matter::OtherBose glassDisordered Systems and Neural Networks (cond-mat.dis-nn)Condensed Matter - Disordered Systems and Neural Networks16. Peace & justiceVariational methodExponentQuantum Physics (quant-ph)
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Traced tensor norms and multiple summing multilinear operators

2016

[EN] Using a general tensor norm approach, our aim is to show that some distinguished classes of summing operators can be characterized by means of an 'order reduction' procedure for multiple summing multilinear operators, which becomes the keystone of our arguments and can be considered our main result. We work in a tensor product framework involving traced tensor norms and the representation theorem for maximal operator ideals. Several applications are given not only to multi-ideals, but also to linear operator ideals. In particular, we get applications to multiple p-summing bilinear operators, (p, q)-factorable linear operators, tau(p)-summing linear operators and absolutely p-summing li…

Multilinear mapAlgebra and Number Theory010102 general mathematicsTensor norm010103 numerical & computational mathematicsSpectral theoremSumming operatorOperator theoryMultiple summing operator01 natural sciencesFourier integral operatorQuasinormal operatorAlgebraLinear mapMultilinear operatorTensor product0101 mathematicsMATEMATICA APLICADAOperator normtau(p)-Summing operatorMathematics
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QuBiLS-MIDAS: A parallel free-software for molecular descriptors computation based on multilinear algebraic maps

2014

The present report introduces the QuBiLS-MIDAS software belonging to the ToMoCoMD-CARDD suite for the calculation of three-dimensional molecular descriptors (MDs) based on the two-linear (bilinear), three-linear, and four-linear (multilinear or N-linear) algebraic forms. Thus, it is unique software that computes these tensor-based indices. These descriptors, establish relations for two, three, and four atoms by using several (dis-)similarity metrics or multimetrics, matrix transformations, cutoffs, local calculations and aggregation operators. The theoretical background of these N-linear indices is also presented. The QuBiLS-MIDAS software was developed in the Java programming language and …

Multilinear mapTheoretical computer scienceSpeedupComputer scienceInterface (Java)business.industryComputationGeneral ChemistryComputational MathematicsTransformation matrixSoftwareTensor (intrinsic definition)ScalabilitybusinessJournal of Computational Chemistry
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