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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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At least 1,135 records · Page 63
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Universal stowage module for future space exploration

The development, design, and fabrication of a prototype storage module, with internal restraints, for the stowage of items that are normally launched to support a space mission are discussed. The primary design criteria was that the storage module be universal in accomodating most sizes and shapes of items that could be launched and returned in a shuttle payload. Mechanical drawings of various types of storage modules are provided.

Seccamp, V. A.↗
NASA NTRS1973

The deuterium puzzle in the symmetric universe

An attempt was made to use deuterium abundance in the symmetric universe to prove that no nucleosynthesis takes place during annihilation and therefore neutrons were loss before nucleosynthesis. Data cover nucleosynthesis during the radiative era, cross section estimates, maximum abundance of He-4 at the end of nucleosynthesis area, and loss rate.

Leroy, B.↗
NASA NTRS1974

The National Aeronautics and Space Administration interdisciplinary studies in space technology at the University of Kansas

A broad range of research projects contained in a cooperative space technology program at the University of Kansas are reported as they relate to the following three areas of interdisciplinary interest: (1) remote sensing of earth resources; (2) stability and control of light and general aviation aircraft; and (3) the vibrational response characteristics of aeronautical and space vehicles. Details of specific research efforts are given under their appropriate departments, among which are aerospace engineering, chemical and petroleum engineering, environmental health, water resources, the remote sensing laboratory, and geoscience applications studies.

Barr, B. G.↗
NASA NTRS1973

University of Hawaii Lure Observatory

The University of Hawaii's Institute for Astronomy is currently constructing a lunar laser ranging observatory at the 3050-meter summit of Mt. Haleakala, Hawaii. The Nd YAG laser system to be employed provides three pulses per second, each pulse being approximately 200 picoseconds in duration. The energy contained in one pulse at 5320 A lies in the range from 250 to 350 millijoules. Details of observatory construction are provided together with transmitter design data and information concerning the lunastat, the feed telescope, the relative pointing system, the receiver, and the event timer system.

Carter, W. E.↗
NASA NTRS1974

Quantum graviton creation in a model universe

Consideration of the mechanism of production of gravitons in the empty, anisotropic, spatially inhomogeneous Gowdy three-torus cosmology. The Gowdy cosmology is an exact solution of the vacuum Einstein equations and is obtained as a generalization of the homogeneous empty Bianchi Type I (Kasner) cosmology by permitting the metric components to depend on one of the space variables in addition to time. The Hamiltonian methods of Arnowitt, Deser, and Misner are employed to identify the dynamical variables which are to be quantized. The WKB regime solution is identical to that found by Doroshkevich, Zel'dovich, and Novikov (DZN) for a universe containing collisionless anisotropic radiation. Using a procedure similar to that of Parker (1971) or Zel'dovich and Starobinskii (1971) for defining quantum number, it is found that the DZN large-time radiation consists of quanta (gravitons) created from an initial vacuum. The quantum behavior is much like the semiclassical enhancement of quantum number with the added feature of creation of quanta from vacuum fluctuations.

Berger, B. K.↗
NASA NTRS1975

Syndrome source coding and its universal generalization

A method of using error-correcting codes to obtain data compression, called syndrome-source-coding, is described in which the source sequence is treated as an error pattern whose syndrome forms the compressed data. It is shown that syndrome-source-coding can achieve arbitrarily small distortion with the number of compressed digits per source digit arbitrarily close to the entropy of a binary memoryless source. A universal generalization of syndrome-source-coding is formulated which provides robustly-effective, distortionless, coding of source ensembles.

Ancheta, T. C., Jr.↗
NASA NTRS1975

University research in aeronautics

The contributions which universities can make to aeronautical research projects are discussed. The activities of several facilities are presented to show the effectiveness of the educational and research programs. Reference is made to the Intergovernmental Personnel Act of 1970 which permits an exchange of federal agency personnel with state and local governments and with public and private higher education schools.

Duberg, J. E.↗
NASA NTRS1975

Investigation of current university research concerning energy conversion and conservation in small single-family dwellings

An investigation was made of university research concerning energy conversion and conservation techniques which may be applied in small single-family residences. Information was accumulated through published papers, progress reports, telephone conversations, and personal interviews. A synopsis of each pertinent investigation is given. Finally, a discussion of the synopses is presented and recommendations are made concerning the applicability of concepts for the design and construction of NASA-Langley Research Center's proposed Technology Utilization House in Hampton, Virginia.

Grossman, G. R.↗
NASA NTRS1974

The spectrum of density perturbations in an expanding universe

The basic dynamic equations that govern the evolution of perturbations in a Friedmann-Lemaitre universe are derived. General solutions describing the evolution of adiabatic perturbations in the density of matter are obtained, and the choice of the appropriate initial conditions is examined. The various perturbation modes are compared, and the effects of decoupling on the perturbation spectrum are studied. The scheme used to follow the evolution of density perturbations through decoupling is based on an extension of the Eddington approximation to the radiative transfer equation, and is strictly valid in both optically thick and thin limits.

Silk, J.↗
NASA NTRS1975

Theories of the origin and nature of the universe

The origin of life on earth is seen arising as a natural consequence of a long series of physical and chemical processes taking place in association with evolution of the universe. The present theory is that any premordial earth atmosphere, resulting from accumulation from the primitive solar nebula, was probably swept away by the very intensive T Tauri stage of the solar wind. Subsequently, the present atmosphere and oceans of the earth were outgassed from the interior. Biochemical components of the gases were mainly water vapor and carbon dioxide.

A. G. W. Cameron↗
NASA NTRS1976

A microprocessor interface for the Ohio university prototype Omega navigation receiver

The Ohio University Omega Prototype Receiver is currently under final design and construction. As initially designed, digital and analog hardware outputs were provided for attachment of tape recorders or chart recording equipment for capture of Omega LOP data. The interface described was designed to demonstrate the concept of direct microprocessor attachment to the existing receiver to allow far more flexibility of output data handling than previously provided.

Lilley, R. W.↗
NASA NTRS1975

The University of Iowa Helios solar wind plasma wave experiment /E 5a/

This document describes the University of Iowa solar wind plasma wave experiment for the Helios missions (Experiment 5a). The objective of this experiment is the investigation of naturally occurring plasma instabilities and electromagnetic waves in the solar wind. To carry out this investigation, the experiment consists primarily of a 16-channel spectrum analyzer connected to the electric field antennas. The spectrum analyzer covers the frequency range from 20 Hz to 200 kHz and has an amplitude dynamic range which extends from .3 microvolts/m to 30 mV/m per channel. This spectrum analyzer, the antenna potential measurements, the shock alarm system and the supporting electronics are discussed in detail.

Gurnett, D. A.↗
NASA NTRS1976

Inhomogeneities in the early universe

The paper investigates certain nonlinear processes that are viable candidates for the mechanisms which produced large-scale inhomogeneities in the early Universe. Several nonlinear Lagrangians are presented for matter, the Korteweg-de Vries equation is analyzed, and the existence of solitons among its solutions is noted. A model based on the possibility of generating a cascade of solitons from an initial perturbation is proposed, and it is shown how large-scale inhomogeneities can be generated when an initial soliton fragments into many others through the nonlinear action of the terms in the Korteweg-de Vries equation. A second model is examined which is based on the interaction of matter with a strong radiation field (an almost monochromatic photon gas) and which involves changes in the refractive index of the vacuum. It is found that matter and radiation will not mix if the radiation field has a nonuniform intensity and that the matter will separate into dense portions or 'cosmological protogalaxies'. The evolution of these portions of matter is studied, and it is found that conditions would be appropriate for the interface between them and the surrounding radiation field to become unstable, giving rise to a turbulent layer.

Canuto, V.↗
NASA NTRS1976

Status review of liquid rocket static test range at Iowa State University

The liquid rocket static test range of the Iowa State University incorporates an Aerobee sustainer propulsion system consisting of a pressure fed (helium) liquid bipropellant (hypergolic) rocket engine with a regeneratively fuel-cooled thrust chamber assembly. The paper covers test results to date (including results of four test firings in the water expulsion mode), construction details of the test stand, the laboratory course syllabus, and the environmental impact statement.

Brodsky, R. F.↗
NASA NTRS1977

Calibration of a universal indicated turbulence system

Theoretical and experimental work on a Universal Indicated Turbulence Meter is described. A mathematical transfer function from turbulence input to output indication was developed. A random ergodic process and a Gaussian turbulence distribution were assumed. A calibration technique based on this transfer function was developed. The computer contains a variable gain amplifier to make the system output independent of average velocity. The range over which this independence holds was determined. An optimum dynamic response was obtained for the tubulation between the system pitot tube and pressure transducer by making dynamic response measurements for orifices of various lengths and diameters at the source end.

Chapin, W. G.↗