Adiabatic theory of charged particle motion.
Adiabatic theory of charged particle motion, considering first-order effects in radius of gyration and Alfven theory
CHARGED PARTICLE↗
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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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First compilation of papers on trajectory analysis and guidance theory
Mathematical models to approximate functions, bounds and power series for three-body problems, satellite orbit theories, and other aspects of trajectory analysis and guidance theory
POWER SERIES↗
The status of stability theory for deterministic systems.
Stability theory application to control, circuit theory and aerospace systems
SYSTEM STABILITY↗
Quasiparticle-ensemble theory for a normal Fermi liquid.
A quasiparticle ensemble ( Q ensemble) is constructed in which the number of quasiparticles with momentum k in the ensemble is conserved. The thermodynamic properties of this ensemble are related to those of the grand canonical ensemble. By comparison with explicit microscopic predictions of the theory, it is shown that this formulation is necessary if the third law of thermodynamics is to be satisfied, and that in this case, the Landau theory of a Fermi liquid follows as a natural consequence.
Quantum mechanics↗
Scattering theory of absorption-line profiles and refractivity.
Attenuation cross section and refractive index using collision theory, calculating resonance profiles of autoionizing lines based on scattering theory
SCATTERING MATRIX↗
Geometric Theory of Functional Differential Equations
Functional differential equations for determining n-dimemensional vector spaces - Liapunov function asymptotic theory of linear systems, and Floquet theory
Hale, J. K.↗
A re-evaluation of the theory for the hydrostatic figure of the earth.
De Sitter hydrostatic theory of earth figure modified to make equations independent of external potential theory in calculating flattening
Khan, M. A.↗
A review of the theories concerning the equatorial F2 region ionosphere.
Causal and semiphenomenological theories concerning equatorial F 2 region, discussing electrodynamic drift theory and transequatorial winds
Goldberg, R. A.↗
Chebyshev minimax control theory
General, closed-form, analytical solutions are determined for certain classes of C-minimax control problems, several alternative mathematical theories are derived, and a controller design theory is developed to give optimal control in the presence of unmeasureable external disturbances.
Johnson, C. D.↗
Third compilation of papers on trajectory analysis and guidance theory
Compilation of technical papers in guidance theory, optimization theory, numerical methods, and celestial mechanics
Source record↗
Toward generalized control theory
Generalized control theory, discussing optimization and table classifying control theory fields
Ho, Y.-C.↗
Stochastic processes and filtering theory
Book on stochastic processes and filtering theory covering probability theory, Markov processes, linear and nonlinear filters, etc
Jazwinski, A. H.↗
Realization theory of rational transfer matrices
Realization theory of rational transfer matrices presented as fundamental algebraic objects in theory of finite, constant linear systems
Wonham, W. M.↗
Quantum-mechanical communication theory
Quantum mechanical communication theory of optimal receivers, using statistical detection and estimation theory
Gordon, J. P.↗
Bias and spread in extreme value theory measurements of probability of error
Extreme value theory is examined to explain the cause of the bias and spread in performance of communications systems characterized by low bit rates and high data reliability requirements, for cases in which underlying noise is Gaussian or perturbed Gaussian. Experimental verification is presented and procedures that minimize these effects are suggested. Even under these conditions, however, extreme value theory test results are not particularly more significant than bit error rate tests.
Smith, J. G.↗
An evaluation of string theory for the prediction of dynamic tire properties using scale model aircraft tires
The string theory was evaluated for predicting lateral tire dynamic properties as obtained from scaled model tests. The experimental data and string theory predictions are in generally good agreement using lateral stiffness and relaxation length values obtained from the static or slowly rolling tire. The results indicate that lateral forces and self-aligning torques are linearly proportional to tire lateral stiffness and to the amplitude of either steer or lateral displacement. In addition, the results show that the ratio of input excitation frequency to road speed is the proper independent variable by which frequency should be measured.
Clark, S. K.↗
A shielding application of perturbation theory to determine changes in neutron and gamma doses due to changes in shield layers
The perturbation theory for fixed sources was applied to radiation shielding problems to determine changes in neutron and gamma ray doses due to changes in various shield layers. For a given source and detector position the perturbation method enables dose derivatives due to all layer changes to be determined from one forward and one inhomogeneous adjoint calculation. The direct approach requires two forward calculations for the derivative due to a single layer change. Hence, the perturbation method for obtaining dose derivatives permits an appreciable savings in computation for a multilayered shield. For an illustrative problem, a comparison was made of the fractional change in the dose per unit change in the thickness of each shield layer as calculated by perturbation theory and by successive direct calculations; excellent agreement was obtained between the two methods.
Fieno, D.↗
Quantitative results of stellar evolution and pulsation theories.
The discrepancy between the masses of Cepheid variables deduced from evolution theory and pulsation theory is examined. The effect of input physics on evolutionary tracks is first discussed; in particular, changes in the opacity are considered. The sensitivity of pulsation masses to opacity changes and to the ascribed values of luminosity and effective temperature are then analyzed. The Cepheid mass discrepancy is discussed in the light of the results already obtained. Other astronomical evidence, including the mass-luminosity relation for main sequence stars, the solar neutrino flux, and cluster ages are also considered in an attempt to determine the most likely source of error in the event that substantial mass loss has not occurred.
Fricke, K.↗