Dipole shielding tensor
Dipole shielding tensor of atom in arbitrary time dependent field, giving conditions for general variational calculations yielding results
Epstein, S. T.↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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A compact method for symbolic computation of the Riemann tensor
Riemann tensor symbolic computation by compact method using differential forms, discussing advantages due to antisymmetry
Harrison, G. H.↗
Lattice-vibrational properties of chromium in the harmonic approximation on the basis of the tensor model
Chromium lattice vibrational properties based on fourth-nearest-neighbor tensor force model, obtaining agreement with inelastic neutron diffraction data and elastic constants
Feldman, J. L.↗
Scalar-tensor theory in canonical form. I
Scalar-tensor theory in canonical form, discussing neutral particle and electron self energy problem
Toton, E. T.↗
Post-Newtonian metric for a general class of scalar-tensor gravitational theories and observational consequences
Space-time Riemann metric for scalar-tensor gravitational theories with arbitrary omega parameter
Nordtvedt, K., Jr.↗
Scalar-tensor theory in canonical form. II - Exact solutions for a static spherically symmetric charged mass distribution
Static spherically symmetric charged mass distribution exact solutions derived for electrons in scalar tensor theory of gravity by Hamilton-Jacobi method
Toton, E. T.↗
Study of different approximations in the calculation of g-tensors: H2(plus)
Approximations in calculating g-tensors for molecular ion H2 (plus)
De Montgolfier, P.↗
The tensor form of the neutron-transport equation with application to finite differencing
Neutron transport equation in five dimensional tensor form, applying finite differencing by integration method via use of divergence theorem
Drawbaugh, D. W.↗
Measurement of the fluorine chemical-shift tensor in MgF2
Fluorine chemical shift tensor measurements in magnesium fluoride, using multiple pulse NMR technique
Elleman, D. D.↗
Solar wind for a magnetized plasma with tensor plasma pressure.
A solar wind model for a magnetized solar wind is presented using one-fluid hydromagnetic equations with generalized polytrope equations of state for the two tensor components of the plasma pressure. Fluid and magnetic field variables are calculated at the Earth using certain boundary conditions at the Sun. The azimuthal velocity agrees with observed values and explains the considerable loss of angular momentum from the Sun by the solar wind. The results are good for most variables but suggest that a two-fluid model with electrons at higher temperatures and smaller temperature anisotropy ratios than the ions would give improved agreement for some quantities.
Tan, M.↗
Modified Brans-Dicke gravitational theory with nonzero divergence of the energy-momentum tensor
The Brans-Dicke theory of gravitation is modified by assuming that the divergence of the energy-momentum tensor is proportional to the covariant derivative of the scalar curvature. No ad hoc additions to the usual Brans-Dicke field equations are required as in Rastall's modification of the Einstein theory or as in the steady-state theories, of which this is a natural possibility. Three parameters emerge from the theory - namely, the unnormalized gravitational constant, the usual Brans-Dicke parameter, and the proportionality constant. In the post-Newtonian approximation, these parameters can be fixed by experiment. However, there exists a certain choice of the parameters for which the theory reduces to an Einstein theory with constant scalar curvature.
Smalley, L. L.↗
A generalized tensor formulation of atmosphere and seas dynamics
A generalized mathematical model was developed for simulation of the dynamics and transport of both the atmosphere and seas. A nearly horizontal bottom coordinate surface conforms to the land-to-air interface and the sea-floor-to-water interface, which simplifies computations. General vertical motion of the other quasi-horizontal coordinate surfaces is allowed; external gravity waves can be represented by the top coordinate surface, and meteorological fronts and inversion layers in the atmosphere and refractive layers in the seas can be represented with enhanced resolution by the internal quasi-horizontal coordinate surfaces. A tensor reformulation of the standard subgrid mixing theory departs significantly from the standard theory in allowing, as a solution under adiabatic conditions, rigid-body rotation of the atmosphere.
Avis, L. M.↗
Gravitational theories with nonzero divergence of the energy-momentum tensor
Assuming that the divergence of the energy-momentum tensor is nonzero leads to a class of theories with consistent field equations and gauge conditions as well as compatibility with the Newtonian limit of the conservation laws. Both the Einstein and the Brans-Dicke theories are used as models, but the extension to other viable theories such as vector-metric and two-metric theories is possible. One particularly interesting theory emerges that agrees with the ordinary Brans-Dicke theory except for the post-Newtonian parameter zeta sub 2, which predicts nonconservation of total momentum. Unfortunately, no accurate experimental limits for this parameter are known. It thus remains for future experiments in lunar-laser ranging to test this theory.
Smalley, L. L.↗
A tensor formulation of the equation of transfer for spherically symmetric flows
A tensor formulation of the equation of radiative transfer is derived in a seven-dimensional Riemannian space such that the resulting equation constitutes a divergence in any coordinate system. After being transformed to a spherically symmetric comoving coordinate system, the transfer equation contains partial derivatives in angle and frequency, as well as optical depth due to the effects of aberration and the Doppler shift. However, by virtue of the divergence form of this equation, the divergence theorem may be applied to yield a numerical differencing scheme which is expected to be stable and to conserve luminosity. It is shown that the equation of transfer derived by this method in a Lagrangian coordinate system may be reduced to that given by Castor (1972), although it is, of course, desirable to leave the equation in divergence form.
Haisch, B. M.↗
A self-documenting source-independent data format for computer processing of tensor time series
The UCLA Space Science Group has developed a fixed format intermediate data set called a block data set, which is designed to hold multiple segments of multicomponent sampled data series. The format is sufficiently general so that tensor functions of one or more independent variables can be stored in the form of virtual data. This makes it possible for the unit data records of the block data set to be arrays of a single dependent variable rather than discrete samples. The format is self-documenting with parameter, label and header records completely characterizing the contents of the file. The block data set has been applied to the filing of satellite data (of ATS-6 among others).
Mcpherron, R. L.↗
Experimental evaluation of the tensor polynomial criterion for designing composite structures
A comprehensive experimental and analytical evaluation of the tensor polynomial failure criterion was undertaken to determine its capability for predicting the ultimate strength of a composite limina subject to a plane stress state. Results are presented demonstrating that a quadratic formulation is too conservative and a cubic representation is required. Strength comparisons with test data derived from glass/epoxy and graphite/epoxy tubular specimens are also provided to validate the cubic strength criterion. Environmental effects including ambient temperature, exposure to vacuum, length of post-cure time, and rate of cool down were also investigated. Behavior changes associated with polymer (epoxy) matrix composites were determined in terms of variations in stiffness and tensile strength.
Tennyson, R. C.↗
Evaluation of the tensor polynomial failure criterion for composite materials
A comprehensive experimental and analytical evaluation of the tensor polynomial failure criterion was undertaken to determine its capability for predicting the ultimate strength of laminated composite structures subject to a plane stress state. Results are presented demonstrating that a quadratic formulation is too conservative and a cubic representation is required. Strength comparisons with test data derived from glass/epoxy and graphite/epoxy tubular specimens are also provided to validate the cubic strength criterion.
Tennyson, R. C.↗