54
54
Sep 20, 2016
09/16
by
Savage, I. Richard
texts
eye 54
favorite 0
comment 0
Topic: Random processes--Testing
80
80
texts
eye 80
favorite 0
comment 0
Topics: Autoregressive series, Random processes
53
53
Sep 20, 2016
09/16
by
Lukacs, Eugene
texts
eye 53
favorite 0
comment 0
Topics: Stochastic processes, Random processes
49
49
texts
eye 49
favorite 0
comment 0
Topics: Random processes--Testing, Airplanes--Trajectories
1,381
1.4K
Jul 6, 2010
07/10
by
Hoshide, R. K.; Nielson, C. E
texts
eye 1,381
favorite 0
comment 0
A program of analysis, design, fabrication, and testing has been conducted to develop and experimentally verify analytical models to predict the effects of impeller blade clearance on centrifugal pumps. The effect of tip clearance on pump efficiency, and the relationship between the head coefficient and torque loss with tip clearance was established. Analysis were performed to determine the cost variation in design, manufacture, and test that would occur between unshrouded and shrouded...
Topics: INDEXES (DOCUMENTATION), INFORMATION THEORY, VISIBILITY, RANDOM PROCESSES, WEATHER FORECASTING
262
262
Jul 6, 2010
07/10
by
KRASNOVSKIY, A. A.; UMRIKHINA, A. V
texts
eye 262
favorite 0
comment 0
THE USE OF MODEL SYSTEMS SIMULATING PREBIOLOGICAL CONDITIONS ON EARTH TO STUDY THE PROBLEM OF THE ABIOGENETIC FORMATION OF PORPHYRINS DURING THE CHEMICAL EVOLUTION PROCESS IS DISCUSSED.
Topics: DISCRETE FUNCTIONS, MATRICES (MATHEMATICS), RANDOM PROCESSES, CORRELATION, DIGITAL FILTERS,...
811
811
Jul 5, 2010
07/10
by
LAPIN, Y. V
texts
eye 811
favorite 0
comment 0
THE THEORETICAL AND EXPERIMENTAL RESULTS OF STUDIES OF PRESSURE DROP, HEAT, AND MASS TRANSFER IN TURBULENT BOUNDARY LAYERS AT SUPERSONIC GAS VELOCITIES ARE DISCUSSED. THE FUNDAMENTALS OF THE MOLECULAR THEORY OF GAS FLOWS, DERIVATIONS OF THE EQUATIONS OF TURBULENT MOTION AND OF THE BOUNDARY LAYER EQUATIONS, IN PARTICULAR FOR THE CASE OF MULTICOMPONENT REACTING GASES ARE PRESENTED. INFORMATION IS GIVEN ON THE KINETICS OF CHEMICAL REACTIONS, INCLUDING THE KINETICS OF DISSOCIATION REACTIONS IN AIR....
Topics: ALGORITHMS, RANDOM PROCESSES, SUNSPOTS, TIME SERIES ANALYSIS, AUTOCORRELATION, EARTH ATMOSPHERE,...
653
653
Jun 15, 2011
06/11
by
Clark, J. A.; Lewis, E. W.; Merte, H., Jr
texts
eye 653
favorite 0
comment 0
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,...
249
249
Jun 1, 2010
06/10
by
Vorobyev, Y. V
texts
eye 249
favorite 0
comment 0
Solution of linear equation Ax equals f using random iteration processes - computer programming
Topics: COMPUTER PROGRAMMING, CONVERGENCE, ITERATION, LINEAR EQUATIONS, RANDOM PROCESSES, COMPUTER...
A representation of nonstationary narrowband random processes in terms of nonstationary quadrature components is proposed in a form analogous to that used to represent wide sense stationary narrowband random processes. The representation is then applied to a specific case in which the nonstationary narrowband random process is generated by the product of white noise and a deterministic periodic signal and then is processed by a narrowband filter. This representation is used in the modeling of...
Topics: Electrical and computer engineering, Nonstationary random processes, Spread spectrum communication,...
283
283
Jul 11, 2010
07/10
by
DELIMARSKIY, Y. K
texts
eye 283
favorite 0
comment 0
RESULTS ARE REVIEWED WHICH WERE OBTAINED IN THE POLAROGRAPHY OF MOLTEN SALTS UTILIZING TERNARY ELECTROLYTES RATHER THAN THE LIQUID CAPILLARY ELECTRODES USED BY STEINBERG AND NACHTREIB, AND SHOWING MATHEMATICAL MODELS CONSISTENLY PREDICTING OUTCOMES WHICH CAN BE PROVEN EMPIRICALLY.
Topics: AIRCRAFT STABILITY, DYNAMIC CONTROL, MARKOV PROCESSES, CIRCULAR ORBITS, DIFFERENTIAL EQUATIONS,...
236
236
Jul 11, 2010
07/10
by
Brune, G. W.; Weber, J. A.; Johnson, F. T.; Lu, P.; Rubbert, P. E
texts
eye 236
favorite 0
comment 0
A method of predicting forces, moments, and detailed surface pressures on thin, sharp-edged wings with leading-edge vortex separation in incompressible flow is presented. The method employs an inviscid flow model in which the wing and the rolled-up vortex sheets are represented by piecewise, continuous quadratic doublet sheet distributions. The Kutta condition is imposed on all wing edges. Computed results are compared with experimental data and with the predictions of the leading-edge suction...
Topics: CONTROL THEORY, DYNAMIC RESPONSE, SCALE MODELS, COMPLEXITY, COORDINATION, DECISION MAKING,...
508
508
Feb 8, 2022
02/22
by
R. L. Stratonovich
texts
eye 508
favorite 5
comment 0
The present book, in two volumes, is concerned with a variety of topics which have been left to one side, as it were, but which are never theless of great practical importance. In particular, we have in mind problems involving the effects of noise on electronic relays and vacuum- tube oscillators. Recently, there has been increased interest in the oper ation of switching devices and self-excited systems, not only because of the development of methods of coherent radar detection, but also in...
Topics: random variables, gaussian processes, markov processes, distribution functions, noise,...
632
632
Sep 24, 2021
09/21
by
V. L. Lebedev
texts
eye 632
favorite 4
comment 0
This book deals with stationary and nonstatlonary ra idom processes in linear systems and in inertialess nonlinear systems which have either one or several in puts and outputs. The application of the mathematical methods expounded is illus trated by many practical examples related to various phys cal and engineering pro blems.
Topics: soviet, physics, engineering, non-linear problems, random force, random processes, linear systems,...
676
676
May 27, 2011
05/11
by
Menon, Sures
texts
eye 676
favorite 0
comment 0
Simulation of turbulent mixing and chemical processes in the near-field plume and plume-vortex regimes has been successfully carried out recently using a reduced gas phase kinetics mechanism which substantially decreased the computational cost. A detailed mechanism including gas phase HOx, NOx, and SOx chemistry between the aircraft exhaust and the ambient air in near-field aircraft plumes is compiled. A reduced mechanism capturing the major chemical pathways is developed. Predictions by the...
Topics: LINEAR SYSTEMS, RANDOM PROCESSES, MECHANICAL PROPERTIES, ELECTRICAL PROPERTIES, NONLINEAR SYSTEMS,...
1,025
1.0K
Jul 11, 2010
07/10
by
Ludwig, L. P
texts
eye 1,025
favorite 0
comment 0
A survey of gas path seals is presented with particular attention given to sealing clearance effects on engine component efficiency. The effects on compressor pressure ratio and stall margin are pointed out. Various case-rotor relative displacements, which affect gas path seal clearances, are identified. Forces produced by nonuniform sealing clearances and their effect on rotor stability are discussed qualitatively, and recent work on turbine-blade-tip sealing for high temperature is described....
Topics: COMPUTERS, NUMERICAL ANALYSIS, RANDOM PROCESSES, STATISTICAL ANALYSIS, COMPUTER PROGRAMMING,...
1,467
1.5K
Jul 11, 2010
07/10
by
Hunt, G. L
texts
eye 1,467
favorite 0
comment 0
No Abstract Available
Topics: RANDOM PROCESSES, WHITE NOISE, ALGORITHMS, BROADBAND, COMPUTERIZED SIMULATION, FOURIER...
231
231
May 27, 2011
05/11
by
Bowman, James S., Jr.; Healy, Frederick M
texts
eye 231
favorite 0
comment 0
A flutter analysis employing the kernel function for three- dimensional, subsonic, compressible flow is applied to a flutter-tested tail surface which has an aspect ratio of 3.5, a taper ratio of 0.15, and a leading-edge sweep of 30 deg. Theoretical and experimental results are compared at Mach numbers from 0.75 to 0.98. Good agreement between theoretical and experimental flutter dynamic pressures and frequencies is achieved at Mach numbers to 0.92. At Mach numbers from 0.92 to 0.98, however, a...
Topics: FLIGHT TESTS, RANDOM PROCESSES, SWEPT WINGS, ERRORS, SAMPLING, RELIABILITY, DISTORTION, FREQUENCY...
293
293
Jun 21, 2010
06/10
by
Colombo, G. V.; Mader, P. P.; Neustein, R. A.; Richardson, D. E
texts
eye 293
favorite 0
comment 0
Atmospheric selection and gravity effects on burning rate and ignition temperature
Topics: CONTINUUM MECHANICS, DISPLACEMENT MEASUREMENT, DYNAMIC STRUCTURAL ANALYSIS, FOUNDATIONS, RANDOM...
234
234
May 23, 2011
05/11
by
Palosz, W.; Grasza, K.; Gillies, D.; Jerman, G
texts
eye 234
favorite 0
comment 0
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...
185
185
Jun 21, 2010
06/10
by
Bailey, H. E.; Fuller, F. B.; Lomax, H
texts
eye 185
favorite 0
comment 0
Numerical difficulties in integrating equations for one dimensional nonequilibrium nozzle flow of gas
Topics: SPACECRAFT, STRUCTURAL ANALYSIS, TRANSFER FUNCTIONS, DYNAMIC RESPONSE, FOURIER TRANSFORMATION,...
258
258
Jul 12, 2010
07/10
by
Lacy, L. L.; Witherow, W. K.; Facemire, B. R.; Nishioka, G. M
texts
eye 258
favorite 0
comment 0
In order to develop a better understanding of separation processes in binary miscibility gap metal alloys, model transparent fluid systems were studied. The system selected was diethylene glycol-ethyl salicylate which has convenient working temperatures (288 to 350 K), low toxicity, and is relatively easy to purify. The system is well characterized with respect to its phase diagram, density, surface and interfacial tensions, viscosity and other pertinent physical properties. Studies of...
Topics: COVARIANCE, THEOREMS, FREQUENCY STABILITY, FUNCTIONS (MATHEMATICS), RANDOM PROCESSES, THEOREM...
233
233
Jun 21, 2010
06/10
by
Sawhill, R. H
texts
eye 233
favorite 0
comment 0
Boeing development of acoustically treated engine-nacelle concept on JT3D low bypass turbofan engine
Topics: ASTROGUIDE NAVIGATION SYSTEM, INERTIAL NAVIGATION, NAVIGATION INSTRUMENTS, DOPPLER NAVIGATION,...
9
9.0
Jun 28, 2020
06/20
by
Rolski, Tomasz
texts
eye 9
favorite 1
comment 0
vi, 139 pages ; 24 cm
Topics: Stationary processes, Point processes, Processus stables, Processus ponctuels, Punktprozess,...
227
227
May 27, 2011
05/11
by
Bandettini, Angelo; Isler, Walter E
texts
eye 227
favorite 0
comment 0
Wind-tunnel tests have been made to determine the location of the boundary-layer transition on three hemispheres having surface roughness (absolute) values of 50, 580, and 2760 microinches. After the initial test run of the smoothest (50 microinch) hemisphere, holes ranging in depth from 1500 to 2500 microinches were noticed in the meridian where transition was observed. The holes were believed to be caused by particles in the air stream. Shadowgraph pictures were obtained of all hemispheres...
Topics: AERODYNAMIC LOADS, FREQUENCY RESPONSE, SWEPT WINGS, FLIGHT TESTS, DEFORMATION, ANALYSIS...
198
198
Jun 21, 2010
06/10
by
Berger, R. J.; Meier, G. W
texts
eye 198
favorite 0
comment 0
Eye movement characteristics of newborn monkeys deprived of patterned vision compared with normal control monkeys
Topics: ALGORITHMS, MAXIMUM PRINCIPLE, RANDOM PROCESSES, NONLINEAR EQUATIONS, OPTIMAL CONTROL, PONTRYAGIN...
A review and a critical discussion are made on the existing methods for analysis of nonstationary time series, and a new algorithm for splitting nonstationary time series, is applied to the analysis of sunspot data.
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, RANDOM PROCESSES, SUNSPOTS, TIME SERIES ANALYSIS,...
Introduction. Heuristic synthesis is used to improve the efficiency of reception and processing of discrete signals under aprior information pressure. The analysis of the decisionmaking algorithm for the linear-logical processing of discrete signals in case of the incomplete aprior data on their parameters is presented. The work objective is to develop and analyze the efficiency of the linear-logical algorithms. Materials and Methods. New mathematical algorithms for the signal reception and...
Topics: decision rules, heuristic synthesis, reception and processing of discrete signals, probability...
An explicit form for a stationary dilation for periodically correlated random processes is obtained. This is then used to give spectral conditions for a periodically correlated process to be non-deterministic, purely deterministic, minimal, and to have a positive angle between its past and future.
Topics: NASA Technical Reports Server (NTRS), CORRELATION, PERIODIC FUNCTIONS, RANDOM PROCESSES, HARMONIC...
Random pulse generator can supply constant-amplitude randomly distributed pulses with average rate ranging from a few counts per second to more than one million counts per second. Generator requires no high-voltage power supply or any special thermal cooling apparatus. Device is uniquely versatile and provides wide dynamic range of operation.
Topics: NASA Technical Reports Server (NTRS), ANALYZERS, LOGIC CIRCUITS, PHYSIOLOGICAL RESPONSES, PULSE...
Subjective ride comfort response ratings were measured on the Langley Visual Motion Simulator with longitudinal acceleration inputs with various power spectra shapes and magnitudes. The results show only little influence of spectra shape on comfort response. The effects of magnitude on comfort response indicate the applicability of psychophysical precepts for comfort modeling.
Topics: NASA Technical Reports Server (NTRS), ACCELERATION TOLERANCE, COMFORT, PASSENGERS, FLIGHT...
A test program to determine the total discomfort associated with vehicle vibration is described. The program utilizes a three-degree-of-freedom vibration simulator to determine the effects of multifrequency and multiaxis vibration inputs. The approach to multifrequency vibration includes a separate consideration of the discomfort associated with each frequency component or band of the total spectrum and a subsequent empirical weighting of the discomfort components of these frequency bands when...
Topics: NASA Technical Reports Server (NTRS), COMFORT, PASSENGERS, VIBRATION SIMULATORS, HUMAN REACTIONS,...
This article takes a preliminary look at the weight distributions achievable for turbo codes using random, nonrandom, and semirandom permutations. Due to the recursiveness of the encoders, it is important to distinguish between self-terminating and non-self-terminating input sequences. The non-self-terminating sequences have little effect on decoder performance, because they accumulate high encoded weight until they are artificially terminated at the end of the block. From probabilistic...
Topics: NASA Technical Reports Server (NTRS), CODERS, CODING, DISTRIBUTION (PROPERTY), PERMUTATIONS, RANDOM...
Observations of lunar transient phenomena for the Association of Lunar and Planetary Observers (ALPO) are reported. The procedures for making visual observations for estimating albedo are described, and the reported albedo analyzed for lunar topographic features. It is shown that a catalog or scale of albedos can be established for each feature.
Topics: NASA Technical Reports Server (NTRS), ALBEDO, LUNAR TOPOGRAPHY, VISUAL OBSERVATION, LUNAR...
The autoregressive (AR) model of a random process is interpreted in the light of the Prony's relation which relates a complex conjugate pair of poles of the AR process in the z-plane (or the z domain) on the one hand, to the complex frequency of one complex harmonic function in the time domain on the other. Thus the AR model of a time series is one that models the time series as a linear combination of complex harmonic functions, which include pure sinusoids and real exponentials as special...
Topics: NASA Technical Reports Server (NTRS), AUTOREGRESSIVE PROCESSES, MAXIMUM ENTROPY METHOD, TIME SERIES...
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...
Some notions of decentralization and coordination in the control of large-scale dynamic systems are discussed. Decentralization and coordination have always been important concepts in the study of large systems. Roughly speaking decentralization is the process of dividing a large problem into subproblems so that it can be handled more easily. Coordination is the manipulation of the subproblem so that the original problem is solved. The various types of decentralization and coordination that...
Topics: NASA Technical Reports Server (NTRS), CONTROL THEORY, DYNAMIC RESPONSE, SCALE MODELS, COMPLEXITY,...
The study of combustion noise from turbofan engines has become important again as the noise from other sources like the fan and jet are reduced. A method has been developed to help identify combustion noise spectra using an aligned and unaligned coherence technique. When used with the well known three signal coherent power method and coherent power method it provides new information by separating tonal information from random process information. Examples are presented showing the underlying...
Topics: NASA Technical Reports Server (NTRS), TURBOFAN ENGINES, JET AIRCRAFT NOISE, COMBUSTION, SIGNAL...
The horizontal locations of craters on Venus are consistent with randomness. However, (1) randomness does not make crater counts useless for age indications; (2) consistency does not imply necessity or optimality; and (3) horizontal location is not the only reference frame against which to test models. Re (1), the apparent smallness of resurfacing areas means that a region on the order of one percent of the planet with a typical number of craters, 5-15, will have a range of feature ages of...
Topics: NASA Technical Reports Server (NTRS), PLANETARY CRATERS, PLANETARY GEOLOGY, RANDOM PROCESSES, VENUS...
Minimum variance estimation requires that the statistics of random observation errors be modeled properly. If measurements are derived through the use of atomic frequency standards, then one source of error affecting the observable is random fluctuation in frequency. This is the case, for example, with range and integrated Doppler measurements from satellites of the Global Positioning and baseline determination for geodynamic applications. An analytic method is presented which approximates the...
Topics: NASA Technical Reports Server (NTRS), ATOMIC CLOCKS, FREQUENCY STANDARDS, RANDOM ERRORS,...
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,...
Randomization tests provide a conceptually simple, distribution-free way to implement significance testing. We have applied this method to the problem of evaluating the significance of the association among a number (k) of variables. The randomization method was the random re-ordering of k-1 of the variables. The criterion variable was the value of the largest eigenvalue of the correlation matrix.
Topics: NASA Technical Reports Server (NTRS), STATISTICAL TESTS, RANDOM PROCESSES, MULTIVARIATE STATISTICAL...
For univariate random sequences, the power spectral density acts like a probability density function of the frequencies present in the sequence. This dissertation extends that concept to bivariate random sequences. For this purpose, a function called the joint spectral density is defined that represents a joint probability weighing of the frequency content of pairs of random sequences. Given a pair of random sequences, the joint spectral density is not uniquely determined in the absence of any...
Topics: NASA Technical Reports Server (NTRS), BIVARIATE ANALYSIS, DENSITY DISTRIBUTION, POWER SPECTRA,...
Methods of interpreting response measurements which could be amenable to flight flutter testing procedures were studied analytically and in the wind tunnel. One suggested scheme, which requires evaluation, is an iterative technique in which derivatives obtained from subcritical response data are used to indicate the approach to flutter. A simplification of this procedure was considered by examining the manner in which a single characteristic of the subcritical response behaves in relation to...
Topics: NASA Technical Reports Server (NTRS), FLIGHT TESTS, FLUTTER, WIND TUNNEL TESTS, EXCITATION,...
A random process is formed by the product of a local Gaussian process and a random amplitude process, and the sum of that product with an independent mean value process. The mathematical properties of the resulting process are developed, including the first and second order properties and the characteristic function of general order. An approximate method for the analysis of the response of linear dynamic systems to the process is developed. The transition properties of the process are also...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, ATMOSPHERIC TURBULENCE, RANDOM PROCESSES,...
An analytical method is developed which combines the equivalent linearization technique for the analysis of the response of nonlinear dynamic systems with the amplitude modulated random process (Press model) for atmospheric turbulence. The method is initially applied to a bilinear spring system. The analysis of the response shows good agreement with exact results obtained by the Fokker-Planck equation. The method is then applied to an example of control-surface displacement limiting in an...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT PERFORMANCE, ATMOSPHERIC TURBULENCE, FOKKER-PLANCK...
In this brief effort, time has been of the essence. The data had to be acquired from APL/Lincoln Labs, stored, and sorted out to obtain the pertinent streams. This has been a significant part of this effort and hardware and software problems have been addressed with the appropriate solutions to accomplish this part of the task. Passed this, some basic and important algorithms are utilized to improve the performance of the attitude estimation systems. These algorithms are an essential part of...
Topics: NASA Technical Reports Server (NTRS), ALGORITHMS, ATTITUDE CONTROL, DISTRIBUTION MOMENTS, SIGNAL...
This study compared random and t-way combinatorial inputs of a network simulator, to determine if these two approaches produce significantly different deadlock detection for varying network configurations. Modeling deadlock detection is important for analyzing configuration changes that could inadvertently degrade network operations, or to determine modifications that could be made by attackers to deliberately induce deadlock. Discrete event simulation of a network may be conducted using random...
Topics: NASA Technical Reports Server (NTRS), COMBINATORIAL ANALYSIS, RANDOM PROCESSES, COMPUTER NETWORKS,...
18,594
19K
Feb 4, 2014
02/14
by
MIT OpenCourseWare
movies
eye 18,594
favorite 3
comment 0
In this collection of 51 videos, MIT Teaching Assistants solve selected recitation and tutorial problems from the course 6.041SC Probabilistic Systems Analysis and Applied Probability. See the 6.041 Probabilistic Systems Analysis and Applied Probability Fall 2010 Internet Archive collection for the video lectures. View the complete course: http://ocw.mit.edu/6-041SCF13 Instructors: Qing He, Jimmy Li, Jagdish Ramakrishnan, Katie Szeto, and Kuang Xu License: Creative Commons BY-NC-SA More...
Topics: probability, statistical inference, Bayesian probability, Markov chains, random processes,...
This paper derives upper bounds on the expected number of search tree nodes visited during an m-solution backtracking search, a search which terminates after some preselected number m problem solutions are found. The search behavior is assumed to have a general probabilistic structure. The results are stated in terms of node expansion and contraction. A visited search tree node is said to be expanding if the mean number of its children visited by the search exceeds 1 and is contracting...
Topics: NASA Technical Reports Server (NTRS), ANALYSIS (MATHEMATICS), RANDOM PROCESSES, SEARCH PROFILES,...
