Search results for "neuma"

showing 10 items of 154 documents

Dynamical behaviour of pneumatic artificial muscles

2014

The mechanical response of pneumatic artificial muscles is analyzed in transient and periodic conditions, assuming the inextensibility of the sheathing fibres and considering the influence of the texture geometry, of the dissipation due to the mutual sliding between the braids and of the stress field inside the bladder thickness, where the constituent elastomer is regarded as a two-parameter Mooney–Rivlin material. The polytropic exponent of the thermodynamic air evolution inside the muscle during the charging and discharging phases may be properly chosen depending on the working frequency. The muscle end shape is taken into account profiling the meridian section by a simple m-degree parabo…

Materials scienceMechanical EngineeringPhysics::Medical PhysicsPolytropic processMechanicsDissipationCondensed Matter PhysicsElastomerSettore ING-IND/13 - Meccanica Applicata Alle MacchineStress fieldBio-robotics Pneumatic artificial muscle Dynamical behaviourPneumatic artificial musclesMechanics of MaterialsControl theoryExponentBraidExcitation
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A theoretical approach to pneumatic muscle mechanics

2013

The mechanical response of pneumatic artificial muscles is analyzed assuming the inextensibility of the sheathing braids and taking into account the stress field inside the rubber bladder, which is regarded as a Mooney-Rivlin hyperelastic material. The end effects are simulated by heuristically profiling the meridian section. After estimating the constitutive parameters by traction tests on rubber specimens, the theoretical results are compared with experiments and a satisfactory accordance may be detected.

Materials sciencePneumatic actuatormedicine.medical_treatmentBio-robotics pneumatic air muscleMechanical engineeringMuscle mechanicsMechanicsTraction (orthopedics)Stress fieldPneumatic artificial musclesNatural rubbervisual_artHyperelastic materialBraidvisual_art.visual_art_mediummedicine2013 IEEE/ASME International Conference on Advanced Intelligent Mechatronics
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A multi-sphere particle numerical model for non-invasive investigations of neuronal human brain activity

2013

In this paper, a multi-sphere particle method is built- up in order to estimate the solution of the Poisson's equation with Neumann boundary conditions describing the neuronal human brain activity. The partial difierential equations governing the relationships between neural current sources and the data produced by neuroimaging technique, are able to compute the scalp potential and magnetic fleld distributions generated by the neural activity. A numerical approach is proposed with current dipoles as current sources and going on in the computation by avoiding the mesh construction. The current dipoles are into an homogeneous spherical domain modeling the head and the computational approach i…

Mathematical optimizationCurrent (mathematics)Quantitative Biology::Neurons and CognitionComputer scienceComputationNon invasiveMathematical analysisDomain modelPoisson distributionElectronic Optical and Magnetic MaterialsDipolesymbols.namesakeBio-magnetic fields Human brain activity meshless numerical methodSettore ING-IND/31 - ElettrotecnicaNeumann boundary conditionsymbolsParticle
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Reconstruction from boundary measurements for less regular conductivities

2012

In this paper, following Nachman's idea and Haberman and Tataru's idea, we reconstruct $C^1$ conductivity $\gamma$ or Lipchitz conductivity $\gamma$ with small enough value of $|\nabla log\gamma|$ in a Lipschitz domain $\Omega$ from the Dirichlet-to-Neumann map $\Lambda_{\gamma}$. In the appendix the authors and R. M. Brown recover the gradient of a $C^1$-conductivity at the boundary of a Lipschitz domain from the Dirichlet-to-Neumann map $\Lambda_{\gamma}$.

Mathematics - Analysis of PDEs35R30Inverse conductivity problemCalderón problemAstrophysics::High Energy Astrophysical PhenomenaBourgain's spaceFOS: MathematicsMathematics::Analysis of PDEsDirichlet-to-Neumann mapMathematics::Spectral TheoryBoundary integral equationAnalysis of PDEs (math.AP)
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The Linearized Calderón Problem in Transversally Anisotropic Geometries

2017

In this article we study the linearized anisotropic Calderon problem. In a compact manifold with boundary, this problem amounts to showing that products of harmonic functions form a complete set. Assuming that the manifold is transversally anisotropic, we show that the boundary measurements determine an FBI type transform at certain points in the transversal manifold. This leads to recovery of transversal singularities in the linearized problem. The method requires a geometric condition on the transversal manifold related to pairs of intersecting geodesics, but it does not involve the geodesic X-ray transform which has limited earlier results on this problem.

Mathematics - Differential GeometryGeodesicGeneral MathematicsNEUMANN MAPBoundary (topology)Type (model theory)01 natural scienceslaw.inventionMathematics - Analysis of PDEslinearized anisotropic Calderón problemlaw35R30 35J25111 MathematicsFOS: Mathematics0101 mathematicsMathematics010102 general mathematicsMathematical analysisInverse problem010101 applied mathematicsHarmonic functionDifferential Geometry (math.DG)Transversal (combinatorics)Gravitational singularityMathematics::Differential GeometryINVERSE PROBLEMManifold (fluid mechanics)Analysis of PDEs (math.AP)
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The metric-valued Lebesgue differentiation theorem in measure spaces and its applications

2021

We prove a version of the Lebesgue Differentiation Theorem for mappings that are defined on a measure space and take values into a metric space, with respect to the differentiation basis induced by a von Neumann lifting. As a consequence, we obtain a lifting theorem for the space of sections of a measurable Banach bundle and a disintegration theorem for vector measures whose target is a Banach space with the Radon-Nikod\'{y}m property.

Mathematics - Functional AnalysisMathematics::Functional AnalysisAlgebra and Number Theorymeasurable Banach bundleLebesgue differentiation theoremFOS: MathematicsRadon–Nikodým propertyBanachin avaruudetdisintegration of a measure28A15 28A51 46G15 18F15 46G10 46B22 28A50von Neumann liftingAnalysisFunctional Analysis (math.FA)
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Spirit and Spirituality: Philosophical Trends in Late Modern Pneumatology

2008

AbstractThis dialogue piece reviews some of the key developments in the doctrine of the Holy Spirit in late modern theology that have contributed to the scholarly and practical integration of pneumatology and Christian spirituality. Shifts in the meaning and use of three concepts — matter, person, and force — have played a particularly influential role in these developments. These trends are illustrated in several recent pneumatological proposals. The final section outlines some new directions for the ongoing task of reforming pneumatology.

Meaning (philosophy of language)media_common.quotation_subjectSpiritualityReligious studiesDoctrinePneumatologySociologySocial scienceEpistemologymedia_commonPneuma
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Boundary discretization based on the residual energy using the SGBEM

2007

Abstract The paper has as objective the estimation of the error in the structural analysis performed by using the displacement approach of the Symmetric Galerkin Boundary Element Method (SGBEM) and suggests a strategy able to reduce this error through an appropriate change of the boundary discretization. The body, characterized by a domain Ω and a boundary Γ−, is embedded inside a complementary unlimited domain Ω∞⧹Ω bounded by a boundary Γ+. In such new condition it is possible to perform a separate valuation of the strain energies in the two subdomains through the computation of the work, defined generalized, obtained as the product among nodal and weighted quantities on the actual boundar…

Meshes optimizationGalerkin approachMechanical EngineeringApplied MathematicsMathematical analysisBoundary (topology)Mixed boundary conditionBoundary knot methodSingular boundary methodCondensed Matter PhysicsRobin boundary conditionSymmetric Boundary Element MethodMaterials Science(all)Mechanics of MaterialsModeling and SimulationModelling and SimulationNeumann boundary conditionFree boundary problemGeneral Materials ScienceCauchy boundary conditionMathematicsInternational Journal of Solids and Structures
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Strong solutions to a parabolic equation with linear growth with respect to the gradient variable

2018

Abstract In this paper we prove existence and uniqueness of strong solutions to the homogeneous Neumann problem associated to a parabolic equation with linear growth with respect to the gradient variable. This equation is a generalization of the time-dependent minimal surface equation. Existence and regularity in time of the solution is proved by means of a suitable pseudoparabolic relaxed approximation of the equation and a passage to the limit.

Minimal surfaceGeneralizationApplied Mathematics010102 general mathematicsMathematical analysis01 natural sciences010101 applied mathematicsStrong solutionsNeumann boundary conditionLimit (mathematics)Uniqueness0101 mathematicsLinear growthAnalysisVariable (mathematics)MathematicsJournal of Differential Equations
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A derivation of the isothermal quantum hydrodynamic equations using entropy minimization

2005

Isothermal quantum hydrodynamic equations of order O(h 2 ) using the quantum entropy minimization method recently developed by Degond and Ringhofer are derived. The equations have the form of the usual quantum hydrodynamic model including a correction term of order O(h 2 ) which involves the vorticity. If the initial vorticity is of order 0(h), the standard model is obtained up to order O(h 4 ). The derivation is based on a careful expansion of the quantum equilibrium obtained from the entropy minimization in powers of h 2 .

Minimisation (psychology)Standard Model (mathematical formulation)Classical mechanicsQuantum hydrodynamicsApplied MathematicsComputational MechanicsOrder (ring theory)Von Neumann entropyVorticityQuantumIsothermal processMathematical physicsMathematicsZAMM
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