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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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Principles of connector testing, design evaluation of commercial connectors, and assessment of design rules for threaded connectors
Operational aspects of steep VTOL approaches as determined by helicopter tests under simulated instrumental flight rules conditions
Retarded long range interaction energies between two like atoms in different energy states, noting selection rules for resonant interactions
Hamiltonian symmetry group role in quantum theory in stationary states classification, transition probabilities and selection rules
Several rules to guide choice of materials, and methods of welding, electroplating, and heat treatment will provide a method for minimizing failures in storage tanks and related hardware. Failures are caused by high-pressure hydrogen effects, the formation of hydrides in titanium, and hydrogen absorption through various metals processing techniques.
A study of empirical methods of predicting tile relative sensitivities of hot cathode ionization gages is presented. Using previously published gage sensitivities, several rules for predicting relative sensitivity are tested. The relative sensitivity to different gases is shown to be invariant with gage type, in the linear range of gage operation. The total ionization cross section, molecular and molar polarizability, and refractive index are demonstrated to be useful parameters for predicting relative gage sensitivity. Using data from the literature, the probable error of predictions of relative gage sensitivity based on these molecular properties is found to be about 10 percent. A comprehensive table of predicted relative sensitivities, based on empirical methods, is presented.
Molecular hydrogen electron scattering, optical refractivity and molecular anisotropy used to construct model dipole spectrum consistent with oscillator strength rules
Elastoplastic flow equations formulation, inverting flow rule to relate stress rates to strain rates and instantaneous stresses, noting Navier equations
Orbit selection rules for planetary cartographic spacecraft derived from relations connecting camera angle, view field and imaging resolution
Optimal rule for decision to stop or continue observation of random variables after observing sequence of variables with continuous distribution function
Gage sensitivity for a particular gas is estimated using the known performance of the gage with a reference gas /nitrogen/ and employing several empirical rules which have usable accuracy. Relative gage sensitivities have been estimated for over 100 gases and vapors.
Investigation is described of methods for obtaining uniform shear stress distribution in adhesives used in double-lap bonded joints. Design rules for reducing adhesive peak shear stresses are listed. Test results of an analysis of straight-lap joint design and stepped-lap joint design are given.
Nonlinear networks computer analysis by recursive decomposition, discussing network graphs construction rules
Diffraction theory, developed in vectorial form and coded into ray tracing routines, permits tracing rays of any wavelength through surfaces that are plane, spherical, conical, or aspheric polynomial. Ruled diffraction gratings may run in either X-direction or Y-direction, where Z is optical axis.
Digital computer program develops temperature control system which maintains various subsystems within proper temperature limits. Coding is simple and input rules are easy to use and remember. Output format is easy to understand and to analyze for error diagnosis.
Context-free language generation using nontrivial constraints on context-sensitive grammar rules
Transport mechanism for holes in polycrystalline Ge films based on Matthiessen rule, considering surface scattering and dislocation
Electron gas problem in metal physics by self consistent Green function formalism, presenting momentum-space Feynman rules and integral equations derivation