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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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Regularization of restricted three-body problem extended to case where three primaries of any mass revolve in circular orbits around common center of mass and fourth body of infinitesimal mass moves in their field
Independent variable changes in dynamical systems and applications to systems regularization, giving canonical and Lagrangian motion equations with tensor notation
Fixed point probability row vector of regular or ergodic transition matrices simplified using generalized matrix inversion theory
Trajectory optimization of space vehicle with continuous thrust based on regularized equations, comparing perturbation method for earth-Jupiter rendezvous transfer
Power series solutions of Thiele-Burrau regularized planar restricted three body problem
Regular crystallographic chain folding in polyethylene crystals
Regular disturbance in topside ionosphere on summer nights from continuous records of ionospheric electron content, discussing magnetic activity and sunspot number effects
Frequencies of charged secondaries numbers emitted from nucleon-nucleon and pion-nucleon inelastic collisions, observing multiplicity regularity
Trajectory optimization of space vehicle with continuous thrust based on regularized equations, comparing perturbation method for earth-Jupiter rendezvous transfer
Coordinate system influence on regularized trajectory optimization problem
Elliptic restricted three body problem singularities dynamical meaning and character, presenting regularization transformations for equations of motion
Continuous thrust spacecraft optimal trajectory regularization, obtaining differential equations for three dimensional motion
Regular multiplicities of particle production in high energy collisions and antinucleon-nucleon annihilation, comparing cosmic ray jet data and pion-nucleon difference
Excising neighborhood of singularity from manifold with vector field definition, making possible regularization of two and three body problems
Regular particle morphology and petrostatistics in Apollo 11 and 12 lunar fines and conglomerates, using phase contrast and scanning microscopes
The Maki contribution to the conductivity above the superconducting transition temperature is regularized within the framework of the BCS theory. This is achieved through the renormalization of the impurity scattering vertex by inclusion of the effects of pair fluctuations. The conductivity is evaluated for a thin film. It depends only on the reduced temperature and the normal resistance per square. Fair agreement is found with Al films over a wide temperature range. Agreement is not found with experiments on Bi, Pb and Ga films, which apparently contain a strong additional pair-breaking effect. The temperature range in which interactions among fluctuations become important in the Maki conductivity is generally larger than that given by the Ginzburg criterion.
A regular hexagonal prism, having a fineness ratio of 1.67, has been tested in a wind tunnel to determine its static aerodynamic characteristics in a low-density hypervelocity flow. The prism tested was a 1/4-scale model of the graphite heat shield which houses the radioactive fuel for the Viking spacecraft auxiliary power supply. The basic hexagonal prism was also modified to simulate a prism on which ablation of one of the six side flats had occurred. This modified hexagonal prism was tested to determine the effects on the aerodynamic characteristics of a shape change caused by ablation during a possible side-on stable reentry.
The Maki contribution to the conductivity above the superconducting transition temperature is regularized within the framework of the BCS theory. This is achieved through the renormalization of the impurity-scattering vertex by inclusion of the effects of pair fluctuations. The conductivity is evaluated for a thin film. It depends only on the reduced temperature and the normal resistance per square. Fair agreement is found with Al films over a wide temperature range. Agreement is not found with experiments on Bi, Pb, and Ga films, which apparently contain a strong additional pair-breaking effect. The temperature range in which interactions among fluctuations become important in the Maki conductivity is generally larger than that given by the Ginzburg criterion.