221
221

May 23, 2011
05/11

by
Eggleston, Robert G

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One mission of the Paul M. Fitts Human Engineering Division of Armstrong Laboratory is to improve the user interface for complex systems through user-centered exploratory development and research activities. In support of this goal, many current projects attempt to advance and exploit user-interface concepts made possible by virtual reality (VR) technologies. Virtual environments may be used as a general purpose interface medium, an alternative display/control method, a data visualization and...

Topics: PHOTONS, NORMAL DENSITY FUNCTIONS, NONLINEARITY, CAVITIES

369
369

May 30, 2011
05/11

by
Folta, David; Cooley, Steven; Howell, Kathleen; Bauer, Frank H

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The Origins' Next Generation Space Telescope (NGST) trajectory design is addressed in light of improved methods for attaining constrained orbit parameters and their control at the exterior collinear libration point, L2. The use of a dynamical systems approach, state-space equations for initial libration orbit control, and optimization to achieve constrained orbit parameters are emphasized. The NGST trajectory design encompasses a direct transfer and orbit maintenance under a constant...

Topics: DESIGN ANALYSIS, NONLINEAR PROGRAMMING, DESIGN OPTIMIZATION, NORMAL DENSITY FUNCTIONS, GENETIC...

176
176

May 29, 2011
05/11

by
Bartels, Robert E.; Gatski, Thomas B

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Three-dimensional transonic flow over a delta wing is investigated with a focus on the effect of transition and influence of turbulence stress anisotropies. The performance of linear eddy viscosity models and an explicit algebraic stress model is assessed at the start of vortex flow, and the results compared with experimental data. To assess the effect of transition location, computations that either fix transition or are fully turbulent are performed. To assess the effect of the turbulent...

Topics: DESIGN ANALYSIS, GENETIC ALGORITHMS, STRATEGY, NORMAL DENSITY FUNCTIONS, REAL VARIABLES,...

629
629

Jun 15, 2011
06/11

by
Clark, J. A.; Lewis, E. W.; Merte, H., Jr

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Film and nucleate boiling of liquid nitrogen in reduced gravity fields with subcooling

Topics: ENTROPY, ESTIMATING, NORMAL DENSITY FUNCTIONS, RANDOM PROCESSES, DATA PROCESSING, DATA REDUCTION,...

http://uf.catalog.fcla.edu/uf.jsp?st=UF000004415&ix=pm&I=0&V=D&pm=1

Topics: Mathematical statistics, Statistiek., Normal density functions., Quality control., Sequential...

193
193

Jul 12, 2010
07/10

by
Yglesias, J. A

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Procedures and techniques are discussed for retrieving payloads that are inertially or local vertical/local horizontal (LVLH) stabilized. Selection of the retrieval profile to be used depends on several factors: (1) control authority of the payload, (2) payload sensitivity to primary reaction control system (PRCS) plumes, (3) whether the payload is inertially or LVLH stabilized, (4) location of the grapple fixture, and (5) orbiter propellant consumption. The general retrieval profiles...

Topics: BIVARIATE ANALYSIS, COMPUTER PROGRAMS, PROBABILITY DISTRIBUTION FUNCTIONS, CORRELATION...

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181

May 31, 2011
05/11

by
Bradshaw, Jeffrey M.; Sierhuis, Maarten; Gawdiak, Yuri; Thomas, Hans; Greaves, Mark; Clancey, William J

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The Personal Satellite Assistant (PSA) is a softball-sized flying robot designed to operate autonomously onboard manned spacecraft in pressurized micro-gravity environments. We describe how the Brahms multi-agent modeling and simulation environment in conjunction with a KAoS agent teamwork approach can be used to support human-centered design for the PSA.

Topics: TRANSPORTATION NETWORKS, ROUTES, ALGORITHMS, SCHEDULES, RANDOM VARIABLES, STOCHASTIC PROCESSES,...

203
203

May 23, 2011
05/11

by
Palosz, W.; Grasza, K.; Gillies, D.; Jerman, G

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Bulk crystals of cadmium-zinc telluride, 23 mm in diameter and up to 45 grams in weight were grown. Controlled seed formation procedure was used to limit the number of grains in the crystal. Most uniform distribution of ZnTe in the crystals was obtained using excess (Cd Zn) pressure in the ampoule.

Topics: EARTH CORE, GEOMAGNETISM, RANDOM PROCESSES, NORMAL DENSITY FUNCTIONS, SCALARS, CORE-MANTLE...

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223

Jul 11, 2010
07/10

by
Brundidge, K. C

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The structure of wakes and how this structure is related to the size and shape of buildings and other obstacles, and to ambient winds, was investigated. Mean values of natural atmospheric flow were obtained and used in conjunction with theoretical relationships developed by dimensional analysis to establish a model of the flow in the wake. Results indicate that conventional and V/STOL aircraft passing through the wake during takeoff and landing would experience not only a change in turbulence...

Topics: LINEAR TRANSFORMATIONS, OPTICAL DATA PROCESSING, ALGORITHMS, NORMAL DENSITY FUNCTIONS, RANDOM...

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263

Jul 12, 2010
07/10

by
Munk, M. M

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Equations are derived to demonstrate which distribution of lifting elements result in a minimum amount of aerodynamic drag. The lifting elements were arranged (1) in one line, (2) parallel lying in a transverse plane, and (3) in any direction in a transverse plane. It was shown that the distribution of lift which causes the least drag is reduced to the solution of the problem for systems of airfoils which are situated in a plane perpendicular to the direction of flight.

Topics: MEAN, NORMAL DENSITY FUNCTIONS, PROBABILITY DISTRIBUTION FUNCTIONS, RANGE (EXTREMES), COMPUTER...

Identical items are simultaneously subjected to stress and operate independently until failure. The authors observe the early failures and use the times of these failure to predict the times of later failures in the same sample. Best linear invariant predictors are derived for location-scale families of failure time distributions, and two simplified predictors are developed. The relative behavior of the predictors is indicated in a table.

Topics: DTIC Archive, Kaminsky, Kenneth S, TECHNOLOGY INC DAYTON OH, *NORMAL DENSITY FUNCTIONS, *SAMPLING,...

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242

Jun 1, 2011
06/11

by
Johnson, Wayne; Yamauchi, Gloria K.; Derby, Michael R.; Wadcock, Alan J

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Wind tunnel measurements and calculations of the aerodynamic interactions between two tiltrotor aircraft in helicopter mode are presented. The measured results include the roll moment and thrust change on the downwind aircraft, as a function of the upwind aircraft position (longitudinal, lateral, and vertical). Magnitudes and locations of the largest interactions are identified. The calculated interactions generally match the measurements, with discrepancies attributed to the unsteadiness of...

Topics: ALGORITHMS, KERNEL FUNCTIONS, METHODOLOGY, MATHEMATICAL MODELS, NORMAL DENSITY FUNCTIONS,...

A model of a single-mode field, initially prepared in a coherent state, coupled to a two-level atom surrounded by a nonlinear Kerr-like medium contained inside a very good quality cavity is considered. We derive the photon number-phase uncertainty relation in the evolution of the field for a weak and strong nonlinear coupling respectively, within the Hermitian phase operator formalism of Pegg and Barnett, and discuss the effects of nonlinear coupling of the Kerr-like medium on photon...

Topics: NASA Technical Reports Server (NTRS), PHOTONS, NORMAL DENSITY FUNCTIONS, NONLINEARITY, CAVITIES,...

425
425

May 31, 2011
05/11

by
Murphy, Patrick C.; Klein, Vladisla

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Improved aerodynamic mathematical models, for use in aircraft simulation or flight control design, are required when representing nonlinear unsteady aerodynamics. A key limitation of conventional aerodynamic models is the inability to map frequency and amplitude dependent data into the equations of motion directly. In an effort to obtain a more general formulation of the aerodynamic model, researchers have been led to a parallel requirement for more general testing methods. Testing for a more...

Topics: ALTIMETRY, NORMAL DENSITY FUNCTIONS, CLOUD PHYSICS, LASER ALTIMETERS, SCATTERING, ANTARCTIC...

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200

May 21, 2011
05/11

by
Wissinger, Alan B.; Noll, Robert J.; Tsacoyeanes, James G.; Tausanovitch, Jeanette R

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This study explores parametrically as a function of wavelength the degrading effects of several common optical aberrations (defocus, astigmatism, wavefront tilts, etc.), using the heterodyne mixing efficiency factor as the merit function. A 60 cm diameter aperture beam expander with an expansion ratio of 15:1 and a primary mirror focal ratio of f/2 was designed for the study. An HDOS copyrighted analysis program determined the value of merit function for various optical misalignments. With...

Topics: COMPUTERIZED SIMULATION, PROBABILITY THEORY, QUALITY CONTROL, RELIABILITY, STATISTICAL ANALYSIS,...

16
16

Apr 27, 2020
04/20

by
Kahn, Peter B

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xiv, 401 pages : 24 cm

Topics: Nichtlineare Dynamik, NONLINEARITY, Normalform, Nonlinear theories, Dynamics, Normal forms...

Evolutionary methods are exceedingly popular with practitioners of many fields; more so than perhaps any optimization tool in existence. Historically Genetic Algorithms (GAs) led the way in practitioner popularity (Reeves 1997). However, in the last ten years Evolutionary Strategies (ESs) and Evolutionary Programs (EPS) have gained a significant foothold (Glover 1998). One partial explanation for this shift is the interest in using GAs to solve continuous optimization problems. The typical GA...

Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, GENETIC ALGORITHMS, STRATEGY, NORMAL DENSITY...

A stochastic approximation algorithm for estimating the proportions in a mixture of normal densities is presented. The algorithm is shown to converge to the true proportions in the case of a mixture of two normal densities.

Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, APPROXIMATION, MIXTURES, STOCHASTIC PROCESSES,...

457
457

May 22, 2011
05/11

by
Verhaagen, N. G.; Jenkins, L. N.; Kern, S. B.; Washburn, A. E

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A low-speed wind-tunnel study of the flow about a 76/40-deg double-delta wing is described for angles of attack ranging from -10 to 25 deg and Reynolds numbers ranging from 0.5 to 1.5 Million. The study was conducted to provide data for the purpose of understanding the vortical flow behavior and for validating Computational Fluid Dynamics methods. Flow visualization tests have provided insight into the effect of the angle of attack and Reynolds number of the vortex-dominated flow both on and...

Topics: DISTRIBUTION FUNCTIONS, ENTROPY, FOKKER-PLANCK EQUATION, HARMONIC OSCILLATORS, NORMAL DENSITY...

164
164

Jul 11, 2010
07/10

by
KRONIG, B.; DUFEY, K.; REINHARDT, P.; JAHNECKE, J.; WOLFF, H. P

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THE METHOD OF MICROCATHETER BLOOD PRESSURE TELEMETRY PERMITS DEEPER INSIGHTS INTO SPONTANEOUS VARIABILITY IN ORDINARY BLOOD PRESSURE. IN LONG TERM MEASUREMENTS ON 77 UNSELECTED HYPERTENSIVES, THE WELL KNOWN CIRCADIAN AND DIURNAL RHYTHMS OF BLOOD PRESSURE WERE DETECTED. THE PATTERNS HAVE THE SAME FORM BUT OCCURRED AT DIFFERENT LEVELS IN THE THREE WHO CATEGORIES OF HYPERTONIA. EXERCISE AND STRESS CAUSED CONSIDERABLE MODIFICATIONS IN THE PROFILE. REGULARITIES WERE OBSERVED IN TIME OF DAY AND...

Topics: LASER DOPPLER VELOCIMETERS, LIGHT BEAMS, LUMINOUS INTENSITY, NORMAL DENSITY FUNCTIONS, ERROR...

No abstract available

Topics: NASA Technical Reports Server (NTRS), HISTOGRAMS, ERRORS, SAMPLING, KURTOSIS, SKEWNESS, NORMAL...

243
243

Jun 12, 2011
06/11

by
Niedra, Janis M

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A uniform B-field approximation model is used to develop design formulas for single-layer wound, toroidal core, ac power inductors that must handle a specified current. Such a geometry is well suited for high temperature, high frequency inductors, where removal of heat from the core becomes critical. Explicit expressions are derived for core radii, core and winding volumes, winding turns and core permeability as functions of a dimensional scaling ratio (S). A limit on the maximum allowed core...

Topics: TURBULENT FLAMES, FLAME PROPAGATION, NORMAL DENSITY FUNCTIONS, TIME DEPENDENCE, TURBULENCE EFFECTS,...

206
206

Jul 11, 2010
07/10

by
Thomas, J. B.; Fliegel, H. F

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Two systems of VLBI (Very Long Baseline Interferometry) are now applicable to earth physics: an intercontinental baseline system using antennas of the NASA Deep Space Network, now observing at one-month intervals to determine UTI for spacecraft navigation; and a shorter baseline system called ARIES (Astronomical Radio Interferometric Earth Surveying), to be used to measure crustal movement in California for earthquake hazards estimation. On the basis of experience with the existing DSN system,...

Topics: NORMAL DENSITY FUNCTIONS, STATISTICAL DISTRIBUTIONS, STOCHASTIC PROCESSES, COMPUTER PROGRAMS,...

665
665

May 21, 2011
05/11

by
Lowe, R. A.; Landis, G. A.; Jenkins, P

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Future space missions may use laser power beaming systems with a free electron laser (FEL) to transmit light to a photovoltaic array receiver. To investigate the efficiency of solar cells with pulsed laser light, several types of GaAs, Si, CuInSe2, and GaSb cells were tested with the simulated pulse format of the induction and radio frequency (RF) FEL. The induction pulse format was simulated with an 800-watt average power copper vapor laser and the RF format with a frequency-doubled...

Topics: HARMONIC OSCILLATORS, MANIFOLDS (MATHEMATICS), QUADRATURES, QUANTUM MECHANICS, QUANTUM OPTICS,...

A study was made of the field size distributions for LACIE test sites 5029, 5033, and 5039, People's Republic of China. Field lengths and widths were measured from LANDSAT imagery, and field area was statistically modeled. Field size parameters have log-normal or Poisson frequency distributions. These were normalized to the Gaussian distribution and theoretical population curves were made. When compared to fields in other areas of the same country measured in the previous study, field lengths...

Topics: NASA Technical Reports Server (NTRS), CHINA, CROP IDENTIFICATION, IMAGING TECHNIQUES, LANDSAT...

A method of linear feature selection for n dimensional observation vectors which belong to one of m populations is presented. Each population has a known apriori probability and is described by a known multivariate normal density function. Specifically we consider the problem of finding a k x n matrix B of rank k (k n) for which the transformed probability of misclassification is minimized. Providing that the transformed a posterior probabilities are distinct theoretical results are obtained...

Topics: NASA Technical Reports Server (NTRS), ERROR ANALYSIS, LINEAR PREDICTION, PROBABILITY DENSITY...

373
373

Jun 21, 2010
06/10

by
NON

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Multiple-mission telemetry system operations with Mariner Mars 69 and Pioneers, and clock synchronization equipment

Topics: ENERGY SPECTRA, VORTICES, LOW TURBULENCE, REYNOLDS NUMBER, TUBE GRIDS, WAVE PROPAGATION, CAUCHY...

A Robbins-Monro type multidimensional stochastic approximation algorithm which converges in mean square and with probability one to the fixed point of a locally contractive regression function is developed. The algorithm is applied to obtain maximum likelihood estimates of the parameters for a mixture of multivariate normal distributions.

Topics: NASA Technical Reports Server (NTRS), APPROXIMATION, MAXIMUM LIKELIHOOD ESTIMATES, STOCHASTIC...

In this paper, the author continues the investigation of response surface methodology in simulation, begun in previous papers. Suppose that g is a linear output function of an input parameter lambda, over some range a or = lambda or = b, and that observations are taken at two parameter settings lambda sub 1 and lambda sub 2. It is shown that if certain conditions are satisfied, then a confidence interval may be obtained for g(lambda) at any point a or = lambda b without making any additional...

Topics: DTIC Archive, Crane, Michael A, CONTROL ANALYSIS CORP PALO ALTO CA, *STATISTICAL ANALYSIS,...

The properties of the truncated distributions for the various families of probability densities have been well discussed in the literature. Also, well known are the expressions for mean, variance and higher order moments of truncated distributions, corresponding to certain families. Johnson and Kotz present an excellent account of these properties almost in every chapter of their four-volume reference work on statistical distributions. This report derives a probability inequality, and then...

Topics: DTIC Archive, Khattree,R, PITTSBURGH UNIV PA CENTER FOR MULTIVARIATE ANALYSIS, *STATISTICAL...

A systematic linear analysis of the perturbations induced by cosmic strings in cold dark matter is presented. The power spectrum is calculated and it is found that the strings produce a great deal of power on small scales. It is shown that the perturbations on interesting scales are the result of many uncorrelated string motions, which indicates a much more Gaussian distribution than was previously supposed.

Topics: NASA Technical Reports Server (NTRS), COSMOLOGY, DARK MATTER, PERTURBATION THEORY, STRING THEORY,...

The effectiveness of a lubricant film preventing metallic contact between two rolling surfaces (such as in ball bearings) as a function of surface roughness parameters was investigated. The parameters considered are the spectral moments of the two-dimensional surface obtained by superposition of the two rolling surfaces. The peak height distribution, estimation of one-dimensional profile spectral moments, and the estimation of two-dimensional surface moments from several profile measurements...

Topics: NASA Technical Reports Server (NTRS), BALL BEARINGS, LUBRICANTS, ASYMPTOTES, FILM THICKNESS, NORMAL...

The paper presents an optimization algorithm that falls in the category of genetic, or evolutionary algorithms. While the bit exchange is the basis of most of the Genetic Algorithms (GA) in research and applications in America, some alternatives, also in the category of evolutionary algorithms, but use a direct, geometrical approach have gained popularity in Europe and Asia. The Bell-Curve Based Evolutionary Algorithm (BCB) is in this alternative category and is distinguished by the use of a...

Topics: NASA Technical Reports Server (NTRS), GENETIC ALGORITHMS, CONTROLLABILITY, NORMAL DENSITY...

An estimation of the number N of communicative civilizations is made by means of Drake's formula which involves the combination of several quantities, each of which is to some extent uncertain. It is shown that the uncertainty in any quantity may be represented by a probability distribution function, even if that quantity is itself a probability. The uncertainty of current estimates of N is derived principally from uncertainty in estimates of the lifetime of advanced civilizations. It is argued...

Topics: NASA Technical Reports Server (NTRS), EXTRATERRESTRIAL COMMUNICATION, EXTRATERRESTRIAL LIFE,...

The standard treatment of RMS surface roughness data is the application of a Gaussian probability distribution. This handling of surface roughness ignores the skew present in the surface and overestimates the most probable RMS of the surface, the mode. Using experimental data we confirm the Gaussian distribution overestimates the mode and application of an asymmetric distribution provides a better fit. Implementing the proposed asymmetric distribution into the optical manufacturing process...

Topics: NASA Technical Reports Server (NTRS), SURFACE ROUGHNESS, NORMAL DENSITY FUNCTIONS, POLISHING,...

Likelihood equations determined by the two types of samples which are necessary conditions for a maximum-likelihood estimate were considered. These equations suggest certain successive approximations iterative procedures for obtaining maximum likelihood estimates. The procedures, which are generalized steepest ascent (deflected gradient) procedures, contain those of Hosmer as a special case.

Topics: NASA Technical Reports Server (NTRS), MAXIMUM LIKELIHOOD ESTIMATES, NORMAL DENSITY FUNCTIONS,...

The class of quasiprobabilities obtainable from the Wigner quasiprobability by convolutions with the general class of Gaussian functions is investigated. It can be described by a three-dimensional, in general, complex vector parameter with the property of additivity when composing convolutions. The diagonal representation of this class of quasiprobabilities is connected with a generalization of the displaced Fock states in direction of squeezing. The subclass with real vector parameter is...

Topics: NASA Technical Reports Server (NTRS), SQUEEZED STATES (QUANTUM THEORY), NORMAL DENSITY FUNCTIONS,...

259
259

May 23, 2011
05/11

by
Wilson, Linda F.; Nicol, David M

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One of the promises of parallelized discrete-event simulation is that it might provide significant speedups over sequential simulation. In reality, high performance cannot be achieved unless the system is fine-tuned to balance computation, communication, and synchronization requirements. As a result, parallel discrete-event simulation needs tools to automate the tuning process with little or no modification to the user's simulation code. In this paper, we discuss our experiments in automated...

Topics: SOLID PROPELLANT ROCKET ENGINES, OXIDES, SPACE SHUTTLES, PLUMES, PARTICLE MASS, STATIC FIRING,...

In the late seventies, an image of the large-scale structure in the Universe began to emerge as a result of the accumulation of the galaxy redshifts. Most of the galaxies are found to concentrate in large filaments and perhaps sheets leaving most of the volume empty. Similar structures were predicted theoretically in the frame of the adiabatic theory of galaxy formation (Zeldovich) and later in the hot dark matter cosmology. However, both scenarios have been ruled out by the observations. With...

Topics: NASA Technical Reports Server (NTRS), DENSITY DISTRIBUTION, GRAVITATION THEORY, NORMAL DENSITY...

A random process is formed by the product of two Gaussian processes and the sum of that product with a third Gaussian process. The resulting total random process is interpreted as the sum of an amplitude modulated process and a slowly varying, random mean value. The properties of the process are examined, including an interpretation of the process in terms of the physical structure of atmospheric motions. The inclusion of the mean value variation gives an improved representation of the...

Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, ATMOSPHERIC TURBULENCE, RANDOM PROCESSES,...

Numerical experiments were conducted to find out the extent to which a Genetic Algorithm (GA) may benefit from a multiprocessor implementation, considering, on one hand, that analyses of individual designs in a population are independent of each other so that they may be executed concurrently on separate processors, and, on the other hand, that there are some operations in a GA that cannot be so distributed. The algorithm experimented with was based on a gaussian distribution rather than bit...

Topics: NASA Technical Reports Server (NTRS), GENETIC ALGORITHMS, OPTIMAL CONTROL, MULTIPROCESSING...

Likelihood equations determined by the two types of samples which are necessary conditions for a maximum-likelihood estimate are considered. These equations, suggest certain successive-approximations iterative procedures for obtaining maximum-likelihood estimates. These are generalized steepest ascent (deflected gradient) procedures. It is shown that, with probability 1 as N sub 0 approaches infinity (regardless of the relative sizes of N sub 0 and N sub 1, i=1,...,m), these procedures converge...

Topics: NASA Technical Reports Server (NTRS), MAXIMUM LIKELIHOOD ESTIMATES, NORMAL DENSITY FUNCTIONS,...

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219

May 31, 2011
05/11

by
Sutliff, Thomas J.; Otero, Angel M.; Urban, David L

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The Physical Sciences Research Program of NASA sponsors a broad suite of peer-reviewed research investigating fundamental combustion phenomena and applied combustion research topics. This research is performed through both ground-based and on-orbit research capabilities. The International Space Station (ISS) and two facilities, the Combustion Integrated Rack and the Microgravity Science Glovebox, are key elements in the execution of microgravity combustion flight research planned for the...

Topics: AIR FLOW, GAS TURBINES, INJECTION, NORMAL DENSITY FUNCTIONS, VERTICAL DISTRIBUTION, AIR JETS, GAS...

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237

May 6, 2010
05/10

by
Merkulenko, V. E

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Energy expression for reflected radar signal from sun corona derived by Gaussian probability distribution of radiowave scattering on electron density inhomogeneities

Topics: CORONAS, CORONA, ELECTRON DENSITY, WAVE SCATTERING, ELECTRON DENSITY (CONCENTRATION), NORMAL...

Topics: DTIC Archive, Anderson, T W, STANFORD UNIV CA DEPT OF STATISTICS, *STOCHASTIC PROCESSES, *TIME...

A general iterative procedure is given for determining the consistent maximum likelihood estimates of normal distributions. In addition, a local maximum of the log-likelihood function, Newtons's method, a method of scoring, and modifications of these procedures are discussed.

Topics: NASA Technical Reports Server (NTRS), ITERATIVE SOLUTION, MAXIMUM LIKELIHOOD ESTIMATES, NORMAL...

The objective of this work was to support the design of improved IUE NEWSIPS high dispersion extraction algorithms. The purpose of this work was to evaluate use of the Linearized Image (LIHI) file versus the Re-Sampled Image (SIHI) file, evaluate various extraction, and design algorithms for evaluation of IUE High Dispersion spectra. It was concluded the use of the Re-Sampled Image (SIHI) file was acceptable. Since the Gaussian profile worked well for the core and the Lorentzian profile worked...

Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, IUE, SYSTEMS ENGINEERING, COMPUTER PROGRAMS,...

Maximum-likelihood estimates are discussed which are based on an unlabeled sample of observations, of unknown parameters in a mixture of normal distributions. Several successive approximation procedures for obtaining such maximum-likelihood estimates are described. These procedures, which are theoretically justified by the local contractibility of certain maps, are designed to take advantage of good initial estimates of the unknown parameters. They can be applied to the signature extension...

Topics: NASA Technical Reports Server (NTRS), MAXIMUM LIKELIHOOD ESTIMATES, NORMAL DENSITY FUNCTIONS,...

505
505

Jul 25, 2010
07/10

by
NON

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No Abstract Available

Topics: ASCENT TRAJECTORIES, SPACECRAFT LAUNCHING, STEERING, WIND EFFECTS, BIAS, BIVARIATE ANALYSIS,...

This document replaces Cape Kennedy empirical wind component statistics which are presently being used for aerospace engineering applications that require component wind probabilities for various flight azimuths and selected altitudes. The normal (Gaussian) distribution is presented as an adequate statistical model to represent component winds at Cape Kennedy. Head-, tail-, and crosswind components are tabulated for all flight azimuths for altitudes from 0 to 70 km by monthly reference periods....

Topics: NASA Technical Reports Server (NTRS), CAPE KENNEDY LAUNCH COMPLEX, NORMAL DENSITY FUNCTIONS, WIND...