Spectrum of turbulence in a plasma with a strong magnetic field
Turbulence spectrum due to density fluctuations in plasma with strong magnetic field, using hydrodynamic theory and Poisson equations
Tchen, C. M.↗
SEARCH · Search NASA
Results for “Poisson”
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.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Evolutionary pattern of specificity regions in light chains of immunoglobulins
Amino acids changes distribution in specificity regions of light polypeptide chains of immunoglobulins showing correspondence with Poisson distribution
Jukes, T. H.↗
How to assemble a Keplerian processor
Computer program for two body problem literal series expansions using Kepler functions with Bessel and Poisson series operation
Broucke, R.↗
Motion of a symmetric gyrostat in a viscous medium
Poisson kinematic equations solution of symmetric gyrostat in viscous medium for free rotor and constant angular speed, using perturbation technique
Kane, T. R.↗
Equivalence of the perturbation theories of Hori and Deprit
Equivalence of perturbation theories of Hori and Deprit, based on Poisson brackets, and computer calculations through sixth order
Campbell, J. A.↗
Sonic boom in turbulence
Poisson density functions and factor analysis of shock wave propagation and sonic boom spectra in turbulent flow
Horning, W. A.↗
Equivalence of the perturbation theories of Hori and Deprit
Hori and Deprit perturbation theories comparison based on Poisson brackets, giving computer program determining functions through sixth order for equivalence proof
Campbell, J. A.↗
Automated algebraic manipulation in celestial mechanics
Automated algebraic manipulation in celestial mechanics, discussing use of Poisson series in perturbation theory problem
Jefferys, W. H.↗
Surface elastic wave propagation studies in lunar rocks
Elastic surface wave amplitude and propagation velocity in lunar rocks, calculating Poisson ratio
Housley, R. M.↗
The application of signal detection theory to optics
The restoration of images focused on a photosensitive surface is treated from the standpoint of maximum likelihood estimation, taking into account the Poisson distributions of the observed data, which are the numbers of photoelectrons from various elements of the surface. A detector of an image focused on such a surface utilizes a certain linear combination of those numbers as the optimum detection statistic. Methods for calculating the false alarm and detection probabilities are proposed. It is shown that measuring noncommuting observables in an ideal quantum receiver cannot yield a lower Bayes cost than that attainable by a system measuring only commuting observables.
Helstrom, C. W.↗
The equilibrium and stability of the gaseous component of the galaxy, 2
A time-independent, linear, plane and axially-symmetric stability analysis was performed on a self-gravitating, plane-parallel, isothermal layer of nonmagnetic, nonrotating gas. The gas layer was immersed in a plane-stratified field isothermal layer of stars which supply a self-consistent gravitational field. Only the gaseous component was perturbed. Expressions were derived for the perturbed gas potential and perturbed gas density that satisfied both the Poisson and hydrostatic equilibrium equations. The equation governing the size of the perturbations in the mid-plane was found to be analogous to the one-dimensional time-independent Schrodinger equation for a particle bound by a potential well, and with similar boundary conditions. The radius of the neutral state was computed numerically and compared with the Jeans' and Ledoux radius. The inclusion of a rigid stellar component increased the Ledoux radius, though only slightly. Isodensity contours of the neutrual or marginally unstable state were constructed.
Kellman, S. A.↗
The equilibrium and stability of the gaseous component of the galaxy, 1
The distribution of gas satisfying hydrostatic and Poisson conditions with distance above the galactic plane is derived and compared with Schmidt's observations of the gas density, rho sub g (z). Equipartition magnetic and cosmic ray (Pc-r) components are assumed. The gas density is calculated for two limiting cases: (1) the total mass density at the galactic plane is equal to the sum of the observed gas and star densities in the solar neighborhood, and (2) Oort's data on the z component of the galactic gravitational acceleration are used. The rms z turbulent gas velocity dispersion is found. An expression is derived for the half-thickness of the equilibrium disk of galactic gas. Using the Innanen galactic mass model, the half-thickness is computed as a function of distance from the galactic center over the range 4kpc or = R or = 14kpc and compared to the observations of McGee and Milton. The observed increase in half-thickness at distances beyond the solar distance is reproduced theoretically. A galactic mass model is derived, using the observed layer half-width and constant value for Q.
Kellman, S. A.↗
Simulation of flight maneuver-load distributions by utilizing stationary, non-Gaussian random load histories
Random numbers were generated with the aid of a digital computer and transformed such that the probability density function of a discrete random load history composed of these random numbers had one of the following non-Gaussian distributions: Poisson, binomial, log-normal, Weibull, and exponential. The resulting random load histories were analyzed to determine their peak statistics and were compared with cumulative peak maneuver-load distributions for fighter and transport aircraft in flight.
Leybold, H. A.↗
NERVA materials development
Materials development topics include: development of analysis techniques to adjust heterogeneous data; determination of thermal conductivity for AISI 347 stainless steel and elastic moduli and Poisson's ratio for Inconel 718 and Ti 5Al-2.5Sn; embrittlement effects of 1400 psi gaseous hydrogen for alloy 718 and Ti 5Al-2.5Sn; cryogenic radiation damage of Ti 5Al-2.5Sn; and evaluation of prepreg, impregnation, and fabric materials for optimum fibrous graphite properties. Component support topics include: tensile design allowable development of Ti 5Al-2.5Sn for turbopump applications; evaluation of fatigue, fracture toughness, and stress corrosion properties of AA 7039-T63 for pressure vessel applications; development of AISI 347 sheet tensile and creep properties for nozzle applications; evaluation of orbital weld techniques for aluminum line fabrication; material selection of shield materials; development of high load friction and wear properties of hard chrome/gold plate combinations; and evaluation of weld processes for NASS duct coolant channel fabrication.
Mandell, B.↗
Statistical accuracy of cosmic radiation neutron component recorders
A method is examined for calculating the error of experimental data from a standard neutron monitor with the multiplicity of neutron generation. It is shown that use of the Poisson distribution to estimate the real statistical error is inadequate. The method proposed is for analysis of low-amplitude periodicities in the cosmic-ray variations.
Dorman, L. I.↗
A digital simulation of message traffic for natural disaster warning communications satellite
Various types of weather communications are required to alert industries and the general public about the impending occurrence of tornados, hurricanes, snowstorms, floods, etc. A natural disaster warning satellite system has been proposed for meeting the communications requirements of the National Oceanic and Atmospheric Administration. Message traffic for a communications satellite was simulated with a digital computer in order to determine the number of communications channels to meet system requirements. Poisson inputs are used for arrivals and an exponential distribution is used for service.
Hein, G. F.↗
Statistical analysis of several terminal area traffic collision hazard factors.
An 11 hr sample of air traffic, comprising 584 tracks recorded at Atlanta during peak periods of August 1967, is analyzed to examine the statistical characteristics of range-guard intrusions and airspace conflicts in a terminal area. The number of intrusions (of an imaginary 3-naut mile, 500-ft range guard surrounding each aircraft) and number of conflicts (of the projected airspace for two aircraft) for a track exhibit Poisson variations with track duration. The hourly rate of intrusions follows the gas model square-law variation with traffic density, but the hourly conflict rate, contrary to the gas model, decreases with greater traffic density.
Ruetenik, J. R.↗
Expansion of the planetary disturbing function.
Some methods are described for the expansion of the disturbing function in planetary theory. One method uses the classical binomial expansion theorem or a successive approximation process derived from it. Another method is a direct application of the Laplace series expansions. For both methods it is proposed to first prepare the series to be manipulated by a scaling operation. These methods can be applied either in a literal or in a numerical form, or any combination of both, but they are especially designed for use on a large scale digital computer with standard Poisson series programs. No usage is made of Newcomb operators or derivatives of Laplace coefficients.
Broucke, R.↗