Modular computer architecture strategy for long term missions
Modular computer design for long term missions, discussing reliability estimation
Bersoff, E.↗
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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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The effect of short term exposures to 100 percent oxygen on the fine structure of proximal convoluted tubules
Short term pure oxygen exposure effects on rats proximal convoluted tubular cell structure
Hess, R. T.↗
On the long-term evolution of lunar satellite orbits
Long term evolution of close low eccentricity lunar satellite orbits, describing lunar gravity effects by spherical harmonic expansion
Vagners, J.↗
Numerical coefficient of the first exchange inhomogeneity term
First exchange energy inhomogeneity term numerical coefficient approximate derivation
Smith, J. R.↗
Predicted term splittings for the Li I, B I, Na I sequences and other sequences with one-electron spectra
Term splitting of Li I, B I, Na I and other sequences with one electron spectra, using screening parameters obtained from Hartree-Fock calculations
Kastner, S. O.↗
Long term storage of relativistic particles in the solar corona
Long term storage of relativistic energetic electrons and protons in solar corona from IMP 4 and Pioneer 8 observations related to delayed emission from flares
Holt, S. S.↗
Broadening of the sodium D lines by atomic hydrogen - An analysis in terms of the NaH molecular potentials
Na D lines broadening by atomic H, discussing interatomic forces between Na and H atoms in terms of NaH molecular potentials
Lewis, E. L.↗
The long term behavior of SNAP-19 generators which use the TAGS thermoelectric material
SNAP 19 TAGS thermoelectric generator life tests at high temperature in Ar, predicting long term performance including thermoelectric material and isotope fuel decay effects
Stapfer, G.↗
Effects of long-term shock and associated stimuli on aggressive and manual responses
Long term exposure to electric shock and associated stimuli on squirrel monkeys, considering aggressive and manual responses
Hutchinson, R. R.↗
Long-term orbital trajectory determination by superposition of gravity and drag perturbations
Long term orbit calculation by superposition of gravity and drag perturbations, taking into account solar and geomagnetic induced density variations
Pimm, R. S.↗
Pupillary responses during a short-term memory task - Cognitive processing, arousal, or both
Eye pupil response during short term memory task, noting postsignal cycle of dilation-constriction
Johnson, D. A.↗
Long term cryogenic storage system integration
Investigations have revealed significant increases in performance when a reliquefier and solar shield in conjunction with a zero-gravity vapor vent system are utilized. Application of a reliquefier and solar shield in long term deep space missions may effect a 60% reduction in propellant loss, compared to that associated with the vapor vent system only. Significant improvements in storage system performance are possible for low earth orbit applicatons; for the typical system that was evaluated, system performance gains were realized for mission durations exceeding 7 days. Spherical solar shields are generally not competitive for low earth orbit applications.
Stonemetz, R. E.↗
Study of advanced techniques for determining the long-term performance of components
A study was conducted of techniques having the capability of determining the performance and reliability of components for spacecraft liquid propulsion applications for long term missions. The study utilized two major approaches; improvement in the existing technology, and the evolution of new technology. The criteria established and methods evolved are applicable to valve components. Primary emphasis was placed on the propellants oxygen difluoride and diborane combination. The investigation included analysis, fabrication, and tests of experimental equipment to provide data and performance criteria.
Source record↗
Ultrastructural changes in rat lung during long-term exposure to oxygen.
The pathogenesis of oxygen toxicity in the lung of rats was studied by electron microscopy. The following long-term effects were established: (1) a progressive destruction of the blood-air barrier beginning with the endothelial cell layer; (2) a profuse edema in the interstitial spaces in the pleural space in the alveoli and in the cytoplasm and organelles; (3) a continuing increase in the quantity and complexity of the alveolar exudate; (4) gradual hemolysis of red blood cells; and (5) eventual subsiding of the interstitial edema in surviving rats with a concomitant development of emphysema.
Harrison, G. A.↗
Advanced research to qualify man for long term weightlessness.
NASA is in the process of conducting a broad program of research and development of technology to qualify, support, and permit the successful use of man in long-term space flight. The technological tasks include human engineering, extravehicular engineering, life support, and human research to assess the effect of space stresses on human physiology and psychology. Various testing techniques that are being used may have future relevance to world health. These include a biocybernetic approach to the study of cardiovascular stresses, measurement of blood flow by means of the Doppler effect, and a device for simulating radiation dosages similar to those produced in solar flares. The planned program includes a study of both humans and animals.
Jones, W. L.↗
Free vibrations of an arbitrary structure in terms of component modes.
A method for the analysis of the free vibrations of an arbitrary structure in terms of component modes is presented based upon the use of the normal, free-free modes of the components in a Rayleigh-Ritz analysis with the constraint or continuity conditions
Dowell, E. H.↗
Explicit expressions of the potential and its derivatives at the origin in terms of the scattering data
The quantum mechanical theory of scattering of a particle by a spherically symmetrical potential is presented. As in the inverse scattering problem, the input of the calculation is the scattering and bound-state data, and the output is data on the potential. The results discussed are explicit expressions for the values of the potential and its derivatives at the origin in terms of the scattering and boundstate data. Various methods to obtain these results are outlined. The presentation is aimed at introducing these various approaches. The simplest scattering problem (nonrelativistic S-wave scattering on a holomorphic potential without bound states) is used as the basis for discussion, and technicalities are omitted whenever possible without loss of clarity. A complete compilation is given of the results obtained to date in this field, including the treatment of higher partial waves and the Klein-Gordon and Dirac equations.
Calogero, F.↗
Experimental program to determine long term characteristics of the MDE pressure transducers
The pressure cell sensors developed for the Pioneer 10/G meteoroid detection experiments (MDE) were investigated to enhance their application and their potential as a sensor in other MDE applications. Their Paschen characteristics were also investigated, and the effects of variations in geometry, Ni-63 platings (for initial ionizations) and sealing pressures were determined. The effects of extensive pre-flight testing and proton and heavy ion space radiation were investigated. Flight-quality pressure panels/cells were committed to long term testing to demonstrate their suitability for the Pioneer 10/G Missions.
Parker, C. D.↗