Food for spaceflight.
Spaceflight food, menu cycles, human waste removal, emergency rations, weight requirement and weightlessness
Bannister, J. R.↗
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Results for “rational”
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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Use of analyticity in the calculation of nonrelativistic scattering amplitudes.
Two body and two channel nonrelativistic scattering amplitudes calculation method using numerical analytic continuation by rational fractions
Schlessinger, L.↗
Continued fraction inversion by Routh's algorithm.
Continued fraction inversion to rational fraction of two polynomials based on state space formulation and Routh algorithm
Chen, C.-F.↗
Dynamic models for viscous fluid transmission lines.
Dynamic models for viscous fluid transmission lines using distributed parameter for accuracy and rational approximate form to avoid computational difficulty
Gerlach, C. R.↗
Circuit minimizes current drain caused by neon indicator lamps
Circuit lights neon lamp by back leakage current of the driving transistor, rather than by the transistors saturation or ''on-state'' current, thereby eliminating lowering of the voltage necessary for indication. Circuit has operating speed greater than indication circuit using a saturation principle and aids in power rationing.
Drylie, C. D.↗
Flutter, vibration, and buckling of truncated orthotropic conical shells with generalized elastic edge restraint
A theoretical investigation has been made of the flutter, vibration, and buckling of truncated conical shells with generalized elastic edge restraint. The shell analysis is of the classical Donnell type, in-plane inertias and structural damping are neglected, and the aerodynamic loading is represented by the inviscid two-dimensional quasi-steady approximation. An approximate solution is obtained by the generalized Galerkin method. The accuracy and limitations of the analysis are illustrated by comparing numerical results for buckling an vibration with results of other investigations for various boundary conditions, applied loads, and shell geometries and stiffness. Sufficient numerical results are presented to permit the determination of the flutter condition for simply supported isotropic conical shells for a wide range of cone angle, length-radius ration, and radius-thickness ratio. Results are also presented to indicate some effects of variations in edge restraint, applied loads, and ring or stringer stiffening.
Flutter↗
US Army food research and development program
Different techniques of preserving food for military field rations
Hollender, H. A.↗
Dry-heat sterilization modeling Interim report
Rational model for spacecraft dry heat sterilization
Brannen, J. P.↗
Analysis of irrational transfer functions for distributed-parameter systems
Algorithmic and digital computer method for approximating irrational transfer functions by rational functions in control systems
Chen, C.-F.↗
Mass spectrometry in structural and stereochemical problems. CLXXII
Mass spectra of 1,2-cyclohexanediol and deuterium labeled analogs data recorded and mechanistic rationalizations of degradation processes given
Djerassi, C.↗
A new class of periodic solutions in the restricted three body problem
Three body problem periodic solutions, considering near equilibrium conservative Hamiltonian system consisting of two harmonic oscillators with rationally related frequencies
Meyer, K. R.↗
A continued fraction generator for smooth pulse sequences
Digital circuit produces rational output pulse rate at fraction of continuous input pulse rate. Output pulses have average rate with least possible deviation from absolute correct time spacing. Circuit uses include frequency synthesizing, fraction generation, and approximation of irrational sequences.
Cohn, M.↗
Calculation of tables of inverses and determinants of finite segments of the Hilbert matrix
Calculating tables of inverses and determinants of finite segments of Hilbert matrices using variable precision rational arithmetic
Cuthill, E.↗
Algebraic test for passivity
Algebraic criterion for positive realness of rational functions, using Routh algorithm
Siljak, D. D.↗
Peak axial-velocity decay with single- and multi-element nozzles
Jet peak-velocity decay data were obtained for a variety of circular and noncircular single-element and multi-element nozzles for application to externally-blown-flap (EBF) STOL aircraft. These data permit a rational approach, in terms of element type and element spacing, to nozzles designed to promote mixing of the jet exhaust with the surrounding air. Rapid mixing and the resulting lower axial jet velocity decreases the noise caused by the interaction of jet impingement on the flap assembly of EBF STOL aircraft. Empirical relationships are presented that permit the prediction of peak axial-velocity decay curves for a wide spectrum of mixer-type nozzles. The data are useful also in the design of ejector-type noise suppressors and for the suppression of VTOL downwash velocities caused by vertically oriented exhaust nozzles.
Vonglahn, U. H.↗
System evaluation from impulse response fragments
By use of rational approximation, a procedure was found which allows calculation of the z-transfer function from a restricted number of time sequence values. The order of the system need not be known. Transformation to the s-domain is easily provided.
Baumeister, J. K.↗
Space shuttle booster multi-engine base flow analysis
A comprehensive review of currently available techniques pertinent to several prominent aspects of the base thermal problem of the space shuttle booster is given along with a brief review of experimental results. A tractable engineering analysis, capable of predicting the power-on base pressure, base heating, and other base thermal environmental conditions, such as base gas temperature, is presented and used for an analysis of various space shuttle booster configurations. The analysis consists of a rational combination of theoretical treatments of the prominent flow interaction phenomena in the base region. These theories consider jet mixing, plume flow, axisymmetric flow effects, base injection, recirculating flow dynamics, and various modes of heat transfer. Such effects as initial boundary layer expansion at the nozzle lip, reattachment, recompression, choked vent flow, and nonisoenergetic mixing processes are included in the analysis. A unified method was developed and programmed to numerically obtain compatible solutions for the various flow field components in both flight and ground test conditions. Preliminary prediction for a 12-engine space shuttle booster base thermal environment was obtained for a typical trajectory history. Theoretical predictions were also obtained for some clustered-engine experimental conditions. Results indicate good agreement between the data and theoretical predicitons.
Tang, H. H.↗
Modular space station detailed preliminary design. Volume 1: Sections 1 through 4.4
Detailed configuration and subsystems preliminary design data are presented for the modular space station concept. Each module comprising the initial space station is described in terms of its external and internal configuration, its functional responsibilities to the initial cluster, and its orbital build up sequence. Descriptions of the subsequent build up to the growth space station are also presented. Analytical and design techniques, tradeoff considerations, and depth of design detail are discussed for each subsystem. The subsystems include the following: structural/mechanical; crew habitability and protection; experiment support; electrical power; environmental control/life support; guidance, navigation, and control; propulsion; communications; data management; and onboard checkout subsystems. The interfaces between the station and other major elements of the program are summarized. The rational for a zero-gravity station, in lieu of one with artificial-gravity capability, is also summarized.
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