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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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Cross section generation and data processing techniques for nuclear rocket shielding methods, modification, updating, and input data preparation - Vol. 3
One dimensional, discrete ordinates transport technique for use with nuclear rocket shielding methods, modification, updating, and data input preparation - Vol. 4
Two dimensional, discrete ordinates transport technique for use with nuclear rocket shielding methods, modification, updating, and data input preparation - Vol. 5
Point kernel techniques for use with nuclear rocket shielding methods, modification, updating, and input data preparation - Vol. 6
Characteristics of self-powered, multichannel digital data buffer designed to expand input capability of electronic scene generator
Input-output properties of feedback systems based on linear time invariate systems
Vibrating element electrometer producing high conversion gain by input current control of elements resonant frequency displacement amplitude
Algorithm for identification of system parameters from input-output data with application to air vehicles
NASTRAN program for input data checkout and undeformed structure plotting
Auxiliary computer routines for generating, checking, and displaying NASTRAN input and output data for analysis of aerospace vehicle structures
Liapunov functions generation for input-output stability of dynamical systems, using causal operator and state space realization
Hybrid decoding technique for symmetrical binary input channels, using bootstrap algorithm across convolutionally encoded information streams
Preamplifier chops and amplifies very low level output of thermopile infrared detectors that will be used to measure thermal energy flux of Jupiter and its departure from a blackbody spectrum. Output signal has negligible phase shift. AC signal is RC-coupled to input stage of other amplifiers.
The study to improve the reliability of the LUT system by discrete input equipment (DIE) is reported. Subjects discussed include: specifications, packaging, aircraft integrated systems, and word formats DIE. It is recommended that maximal use of advanced technology be made, particularly the "know how' developed on the Saturn project.
The capability of graphic input/output systems is described. Topics considered are a character recognizer and dictionary building program, an initial flow chart element input program, and a system entitled The Assistant Mathematician, which uses ordinary mathematics to specify numeric computation. All three parts are necessary to allow a user to carry on a mathematical dialogue with the computer in the language and notation of his discipline or problem domain.
Recently improved sufficient conditions for the Lp stability of multiple-input multiple-output linear time-invariant feedback systems are given. The continuous-time case is done in detail; the discrete-time case is outlined. Unstable open-loop systems with singular residue matrices are allowed.
It is shown that the full order adaptive observer for single input, single output, observable, continuous, stable, linear differential systems in the absence of a deterministic or random disturbance vector guarantees the vanishing of observation error, regardless of the size of the constant or slowly varying parameter ignorance. The observer parameters are directly changed in a Liapunov adaptive way so as to eventually yield the unknown full order Luenberger observer. The observer poles throughout may be placed freely in the stable region and no derivatives are required in the adaptive law.
A new method of extracting aircraft stability and control derivatives from flight test data is developed based on the maximum likelihood cirterion. It is shown that this new method is capable of processing data from both linear and nonlinear models, both with and without process noise and includes output error and equation error methods as special cases. The first application of this method to flight test data is reported for lateral maneuvers of the HL-10 and M2/F3 lifting bodies, including the extraction of stability and control derivatives in the presence of wind gusts. All the problems encountered in this identification study are discussed. Several different methods (including a priori weighting, parameter fixing and constrained parameter values) for dealing with identifiability and uniqueness problems are introduced and the results given. The method for the design of optimal inputs for identifying the parameters of linear dynamic systems is also given. The criterion used for the optimization is the sensitivity of the system output to the unknown parameters. Several simple examples are first given and then the results of an extensive stability and control dervative identification simulation for a C-8 aircraft are detailed.