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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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Asymptotic relation between Thomas-Fermi-Dirac and Thomas-Fermi atom models for pressure with and without exchange, considering Coulomb contribution to energy
Magnetic monopole flux limits in primary cosmic radiation derived from muon-poor shower data and inverse Compton scattering
Actuating signal at sampling instants determined in phase plane by Mullin-Jury method for sampled data feedback containing quantizer and zero order hold circuit
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Computer program speeds up design process of tension springs and simultaneously optimizes the design by varying the input.
Characteristics of viscous gases flowing between two relatively rotating coaxial cylinders
Support for flexible conductor cable between drawers or racks holding electronic equipment and cabinet assembly housing drawers or racks
Expressions for electrical conductivity of plasmas applied to equilibrium air at 3000 to 28,000 K
Graph theory and its applications - bibliography, supplement 1
Quasi-Newtonian minimization methods extended to infinite dimensional Hilbert space with applications to optimal control problems
Hybrid computers solution of linear differential equations, analyzing Taylor series /derivatives/ use for compensation
Continuous media nonlinear thermomechanical behavior, presenting finite element formulation of deformation and irreversible thermodynamics problems
Modified asymptotic perturbation expansion method application to free flow rotation effect on boundary layer for hypersonic flow about blunt body
A generalized covariance analysis technique which permits the study of the sensitivity of linear estimation algorithms to errors in a priori statistics has been developed and programed. Several sample cases are presented to illustrate the use of this technique. Modifications to the Simulated Trajectories Error Analysis Program (STEAP) to enable targeting a multiprobe mission of the Planetary Explorer type are discussed. The logic for the mini-probe targeting is presented. Finally, the initial phases of the conversion of the Viking mission Lander Trajectory Reconstruction (LTR) program for use on Venus missions is discussed. An integrator instability problem is discussed and a solution proposed.
In order to define a system which would significantly reduce payload delivery costs, activities were extended to modifications of the reusable space shuttle design concept. Considered were systems using orbiters with external propellant tanks and an interim expendable booster which allowed phased development of the usable orbiter and booster. Analyzed were: Merits of internal and external propellant tanks and the impact of external LH2 compared to L02 and LH2; impact of cargo bay size; impact abort; merit of expendable booster options; and merit of a phased development program. Studies showed that external L02/LH2 and the continued use of the J-2S engine on the orbiter reduced program cost and risk.
Progress in the modular space station development program is reported. The space station project office organization and the manner in which the center interfaces with NR are presented along with a sortie and experiment analysis. The operations, subsystems and configurations are reviewed, and future activities are listed.
The general, operational, design/construction, and subsystem design requirements are presented for a solar powered modular space station system. While these requirements apply only to the initial station system, the system is readily adaptable to a growth configuration.
The interface requirements between the modular space station (MSS) and the space shuttle cover both the ground and orbital phases of operation from the launch of the first MSS module until the initial modular station has been manned and in routine operation. As a point of reference, the NR two-stage, fully reusable space shuttle, whose definition has been obtained from the space shuttle Phase B definition studies, has been selected around which the interface requirements have been described.