Asteroid families and ''jet streams''
Asteroid families and jet streams, searching for regularities and resonances in mean family elements
Arnold, J. R.↗
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Results for “regularization”
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 bending of space curves into piecewise helical curves
Regular C cubed space curve bending in Euclidean 3-space into piecewise helix, considering torsion and curvature
Sloss, J. M.↗
Spatially homogeneous world models
Einstein field equations for spatially homogeneous spaces, considering rotating matter model in regularized Euler-Lagrange form
Ozsvath, I.↗
Manpower management information system /MIS/
System of programs capable of building and maintaining data bank provides all levels of management with regular manpower evaluation reports and data source for special management exercises on manpower.
Gravette, M. C.↗
Dwarfing, lignification, and land plant evolution
Investigating relationship of lignin content to height in dwarf and regular-sized alpine plants of Iceland
Siegel, S. M.↗
An analysis of thermal soundings of the atmosphere from satellites
Atmospheric temperature profile from satellite soundings of outgoing radiation in IR carbon dioxide band, using regularization and Chahine methods
Conrath, B. J.↗
Periodic collision orbits in the elliptic restricted three-body problem
Two dimensional elliptic restricted three body problem, considering regularization mechanism and periodic collision orbits
Broucke, R.↗
An improved aesthesiometer
Biomedical tool measures cutaneous sensory perception by allowing consistent application of regular and determinable pressure to skin of the individual. Device is of relatively simple construction, inexpensive to manufacture, and easy to operate.
Wright, D.↗
Experiment M411: Two color earth limb photography
Some simple calculations were made regarding the scattered light phenomenon of a sunlit earth limb. It was assumed that the light was to be scattered by an atmosphere irradiated by a zenith sun. Calculations were made with several different scattering coefficients assignable to various wavelengths of the extended visual region. The dependence of the excess blue-limb elevation was less obviously determined by the scattering angle than was suspected. It is reasonable to surmise that the variation of the values of excess blue-limb elevation originated principally from the red-limb variance, because the form of the blue-limb profiles (at least in their upper part) was more regular than was that of the red-limb profiles.
Petersen, M.↗
Control of functional differential equations to target sets in function space
Optimal control of systems governed by functional differential equations of retarded and neutral type is considered. Problems with function space initial and terminal manifolds are investigated. Existence of optimal controls, regularity, and bang-bang properties are discussed. Necessary and sufficient conditions are derived, and several solved examples which illustrate the theory are presented.
Banks, H. T.↗
Diffraction of a plane wave by a three-dimensional corner
By the superposition of the conical solution for the diffraction of a plane pulse by a three dimensional corner, the solution for a general incident plane wave is constructed. A numerical program is presented for the computation of the pressure distribution on the surface due to an incident plane wave of any wave form and at any incident angle. Numerical examples are presented to show the pressure signature at several points on the surface due to incident wave with a front shock wave, two shock waves in succession, or a compression wave with same peak pressure. The examples show that when the distance of a point on the surface from the edges or the vertex is comparable to the distance for the front pressure raise to reach the maximum, the peak pressure at that point can be much less than that given by a regular reflection, because the diffracted wave front arrives at that point prior to the arrival of the peak incident wave.
Ting, L.↗
A program for identification of linear systems
A program has been written for the identification of parameters in certain linear systems. These systems appear in biomedical problems, particularly in compartmental models of pharmacokinetics. The method presented here assumes that some of the state variables are regularly modified by jump conditions. This simulates administration of drugs following some prescribed drug regime. Parameters are identified by a least-square fit of the linear differential system to a set of experimental observations. The method is especially suited when the interval of observation of the system is very long.
Buell, J.↗
Optimal filter design subject to output delobe constraints
The design of filters for detection and estimation in radar and communications systems is considered, with inequality constraints on the maximum output sidelobe levels. A constrained optimization problem in Hilbert space is formulated, incorporating the sidelobe constraints via a partial ordering of continuous functions. Generalized versions (in Hilbert space) of the Kuhn-Tucker and Duality Theorems allow the reduction of this problem to an unconstrained one in the dual space of regular Borel measures. A convergent algorithm is presented for computational solution of the dual problem.
Fortmann, T. E.↗
Lifting-surface theory for calculating the loading induced on a wing by a flap
A method is described for using lifting-surface theory to obtain the pressure distribution on a wing with a trailing-edge flap or control surface. The loading has a logarithmic singularity at the flap edges, which may be determined directly by the method of matched asymptotic expansions. Expressions are given for the singular flap loading for various flap hinge line and side edge geometries, both for steady and unsteady flap deflection. The regular part of the flap loading must be obtained by inverting the lifting-surface-theory integral equation relating the pressure and the downwash on the wing: procedures are described to accomplish this for a general wing and flap geometry. The method is applied to several example wings, and the results are compared with experimental data. Theory and test correlate well.
Johnson, W. A.↗
Infrared Absorption of Carbon Dioxide at High Densities With Application to the Atmosphere of Venus
Several new infrared absorptions were found in carbon dioxide. All are normally forbidden, and were collision-induced in an absorbing cell whose combination of pressure and path length has a unique sensitivity for induced absorptions. The new absorptions in the 2.3 micron region are attributed to transitions from ground to the 3(1)1 Fermi pair at 4248 and 4391/cm. Other absorptions are attributed to simultaneous CO2-N2 transitions and to the 00(0)0-00(0)2 transition in CO2 polarizability derivatives and regular progressions in strength versus increasing quantum number. The spectra were used to predict the radiative transfer in a dry CO2 model of the lower Venus atmosphere. The results indicate that the radiation balance in the lower atmosphere is adequately explained by a dry massive atmosphere of CO2 with a layer of infrared-opaque clouds. The absorptions in the 2.3 micron region are significant in accounting for the opacity to sustain Venus' 768 K surface temperature.
John Fitzallen Moore↗
Results of measurement of radio wave absorption in the ionosphere by the AI method
Median noon absorption values for each month from 1964 through 1967, the diurnal variations of absorption on the regular world days, and the seasonal variations of absorption are given. The dependence of the absorption coefficient on sunspot number is analyzed.
Korinevskaya, N. A.↗
Radio Astronomy Explorer (RAE) 1 observations of terrestrial radio noise
Radio Astonomy Explorer (RAE) 1 data are analyzed to establish characteristics of HF terrestrial radio noise at an altitude of about 6000 km. Time and frequency variations in amplitude of the observed noise well above cosmic noise background are explained on the basis of temporal and spatial variations in ionospheric critical frequency coupled with those in noise source distributions. It is shown that terrestrial noise regularly breaks through the ionosphere and reaches RAE with magnitudes 15 or more db higher than cosmic noise background. Maximum terrestrial noise is observed when RAE is over the dark side of the Earth in the neighborhood of equatorial continental land masses where thunderstorms occur most frequently. The observed noise level is 30-40 db lower with RAE over oceans.
Herman, J. R.↗
Shear free, twisting Einstein-Maxwell metrics in the Newman-Penrose formalism
The problem of finding algebraically special solutions to the vacuum Einstein-Maxwell equations was investigated using a spin coefficient formalism. The general case in which the degenerate null vectors are not hypersurface orthogonal is reduced to a problem of solving five coupled differential equations that are no longer dependent on the affine parameter along the degenerate null directions. It is shown that the most general regular, shear-free, nonradiating solution to these equations is the Kerr-Newman metric.
Lind, R. W.↗