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  • Other Sources  (2,950)
  • GEOPHYSICS  (1,328)
  • AERODYNAMICS  (845)
  • COMMUNICATIONS AND RADAR  (451)
  • SPACECRAFT PROPULSION AND POWER  (326)
  • 1980-1984  (2,950)
  • 1950-1954
  • 1925-1929
  • 1983  (1,458)
  • 1981  (1,492)
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  • Other Sources  (2,950)
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  • 1980-1984  (2,950)
  • 1950-1954
  • 1925-1929
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  • 1
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    Curved-flow, rolling-flow, and oscillatory pure-yawing wind-tunnel test methods for determination of dynamic stability derivatives (1981)
    In:  CASI
    Details
    Publication Date: 2011-10-14
    Description: The test capabilities of the Stability Wind Tunnel of the Virginia Polytechnic Institute and State University are described, and calibrations for curved and rolling flow techniques are given. Oscillatory snaking tests to determine pure yawing derivatives are considered. Representative aerodynamic data obtained for a current fighter configuration using the curved and rolling flow techniques are presented. The application of dynamic derivatives obtained in such tests to the analysis of airplane motions in general, and to high angle of attack flight conditions in particular, is discussed.
    Keywords: AERODYNAMICS
    Type: AGARD Dyn. Stability Parameters; 13 p
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  • 2
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    The tectonics of anorthosite massifs (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: Anorthosite massifs developed approximately 1.4 to 1.5 billion years ago along an arch which developed parallel to a zone of continental separation as a block which included North America, Europe, and probably Asia separated from a block which included parts of South America, Africa, India, and Australia. Anorthosite massifs also developed at the same time along a belt which runs through the continents which comprise Gondwanaland (South America), Africa, India, Australia, and Antarctica. This was a zone of continental separation which subsequently became a zone of continental collision about 1.2 billion years ago. The northern anorthosite belt also parallels an orogenic belt which was active between 1.8 and 1.7 billion years ago. Heat generated during this mountain building period helped in the formation of the anorthosites.
    Keywords: GEOPHYSICS
    Type: Houston Univ. The 1981 NASA ASEE Summer Fac. Fellowship Program, Vol. 2; 29 p
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  • 3
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    Low-energy electron flux and its reaction to active experimentation of Spacelab (1981)
    In:  CASI
    Details
    Publication Date: 2006-06-04
    Description: An instrument capable of observing the natural electron flux in the energy range from 0.1 to 12.0 kiloelectron volts is discussed for use in an experiment intended as a forerunner of a method that will utilize artificially accelerated electrons as tracer particles for electron fields parallel to the magnetic field. Effects that are of importance either as means of detecting the echo beam or as causes of beam perturbations (e.g., spacecraft charging effects and electron background) are to be studied. The use of electron accelerators as a tool to probe magnetospheric processes rather than to modify them is planned.
    Keywords: GEOPHYSICS
    Type: NASA. Marshall Space Flight Center Spacelab Mission 1 Expt. Descriptions; 3 p
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  • 4
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    Atmospheric emission photometric imaging (1981)
    In:  CASI
    Details
    Publication Date: 2006-06-04
    Description: A dual-channel video system mounted on a stabilized two-axis gimbal system (mounted on the pallet) with associated optics and data handling electronics described the low light flux observations are required for: (1) investigating ionospheric transport processes by observing Mg+ ions; (2) supporting magnetospheric electron bounce experiments; (3) measuring electron cross sections for selected atmospheric species; (4) detecting small particle contamination; and (5) studying natural auroras.
    Keywords: GEOPHYSICS
    Type: NASA. Marshall Space Flight Center Spacelab Mission 1 Expt. Descriptions; 4 p
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  • 5
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    DC-magnetic field vector measurement (1981)
    In:  CASI
    Details
    Publication Date: 2006-06-04
    Description: A magnetometer experiment was designed to determine the local magnetic field by measuring the total of the Earth's magnetic field and that of an unknown spacecraft. The measured field vector components are available to all onboard experiments via the Spacelab command and data management system. The experiment consists of two parts, an electronic box and the magnetic field sensor. The sensor includes three independent measuring flux-gate magnetometers, each measuring one component. The physical background is the nonlinearity of the B-H curve of a ferrite material. Two coils wound around a ferrite rod are necessary. One of them, a tank coil, pumps the ferrite rod at approximately 20 kilohertz. As a consequence of the nonlinearity, many harmonics can be produced. The second coil (i.e., the detection coil) resonates to the first harmonic. If an unknown dc or low-frequency magnetic field exists, the amplitude of the first harmonic is a measure for the unknown magnetic field. The voltages detected by the sensors are to be digitized and transferred to the command and data management system.
    Keywords: GEOPHYSICS
    Type: NASA. Marshall Space Flight Center Spacelab Mission 1 Expt. Descriptions; 2 p
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  • 6
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    Investigation on Atmospheric H and D through the measurement of their Lyman-alpha emissions (1981)
    In:  CASI
    Details
    Publication Date: 2006-06-04
    Description: Study of sources of Lyman-alpha emission in the atmosphere, in the interplanetary medium, and perhaps in the galactic medium is planned. Sources of Lyman-alpha emission are described and a schematic of the instrument presented.
    Keywords: GEOPHYSICS
    Type: NASA Marshall Space Flight Center Spacelab Mission 1 Expt. Descriptions; 3 p
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  • 7
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    Space experiments with particle accelerators (1981)
    In:  CASI
    Details
    Publication Date: 2006-06-04
    Description: The purpose of space experiments with particle accelerators (SEPAC) is to carry out active and interactive experiments on and in the Earth's ionosphere and magnetosphere. It is also intended to make an initial performance test for an overall program of Spacelab/SEPAC experiments. The instruments to be used are an electron beam accelerator, magnetoplasma dynamic arcjet, and associated diagnostic equipment. The accelerators are installed on the pallet, with monitoring and diagnostic observations being made by the gas plume release, beam-monitor TV, and particle-wave measuring instruments also mounted on the pallet. Command and display systems are installed in the module. Three major classes of investigations to be performed are vehicle charge neutralization, beam plasma physics, and beam atmosphere interactions. The first two are mainly onboard plasma physics experiments to measure the effect of phenomena in the vicinity of Spacelab. The last one is concerned with atmospheric modification and is supported by other Spacelab 1 investigations as well as by ground-based, remote sensing observations.
    Keywords: GEOPHYSICS
    Type: NASA. Marshall Space Flight Center Spacelab Mission 1 Expt. Descriptions; 4 p
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  • 8
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    Ozone and aircraft operations (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: The cabin ozone problem is discussed. Cabin ozone in terms of health effects, the characteristics of ozone encounters by aircraft, a brief history of studies to define the problem, corrective actions taken, and possible future courses of action are examined. It is suggested that such actions include avoiding high ozone concentrations by applying ozone forecasting in flight planning procedures.
    Keywords: GEOPHYSICS
    Type: NASA. Marshall Space Flight Center Proc.: 5th Ann. Workshop on Meteorol. and Environ. Inputs to Aviation Systems; p 40-44
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  • 9
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    Prediction techniques (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: Prediction methods and related propagation results for the evaluation of Earth-space communication paths operating above 10 GHz are presented. Gaseous attenuation, rain, cloud, fog, sand, and dust attenuation, path diversity, signal fluctuations and low angle fading, depolarization effects, bandwidth coherence, and sky noise are considered.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Propagation Effects Handbook for Satellite Systems Design; p 195-348
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  • 10
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    Characteristics of rain and rain systems (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: The description and measurement of the macroscopic and microscopic characteristics of rain and rain systems are discussed. The statistical relationships of these characteristics and their effect on polarization and attenuation are considered. Macroscopic characteristics include the size, distribution, and movements of rain cells, the height of melting layers, and the presence of ice crystals. Microscopic characteristics include the size distribution, density, and oblateness of rain drops and ice crystals. The estimation of a major propagation effect, specific attenuation, is described.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Propagation Effects Handbook for Satellite Systems Design; p 5-39
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  • 11
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    Space shuttle main engine: Hydraulic system (1981)
    In:  CASI
    Details
    Publication Date: 2006-01-16
    Description: The hydraulic actuation system of the space shuttle main engine is discussed. The system consists of five electrohydraulic actuators and a single engine filter used to control the five different propellant valves, which in turn control thrust and mixture ratio of the space shuttle main engine. The hydraulic actuation system provides this control with a precision of 98.7 percent or an error in position no greater than 1.3 percent of full scale rotational travel for critical positions.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: the 15th Aerospace Mech. Symp.; p 291-301
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  • 12
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    SRB dewatering set (1981)
    In:  CASI
    Details
    Publication Date: 2006-01-16
    Description: The system components and operation of the space shuttle solid rocket booster (SRB) dewatering set are described. The SRB dewatering set consists of a nozzle plug, control console, remote control unit, power distribution unit, umbilical cable, interconnect cables, and various handling and storage items. The nozzle plug (NP) is a remotely controlled, tethered underwater vehicle that is launched from the retrieval vessel (RV) by a crane, descends down the side of the SRB, and is positioned below the SRB nozzle. A TV camera mounted at the top of the NP central core is used by the control console operator to visually guide the NP during descent and docking. The NP is then driven up and locked into the nozzle. Compressed air is passed through the umbilical from the RV, through the NP and into the SRB motor. The water inside the SRB is expelled causing the SRB to rotate to a near horizontal attitude on the surface of the water.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: NASA. Marshall Space Flight Center The 15th Aerospace Mech. Symp.; p 279-289
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  • 13
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    Zero gravity testing of flexible solar arrays (1981)
    In:  CASI
    Details
    Publication Date: 2006-01-16
    Description: Zero gravity testing in the KC-135 aircraft of flat fold flexible solar array test specimens sufficiently demonstrated the adequacy of the panel design. The aircraft flight crew provided invaluable assistance and significantly contributed to the design and development of the flexible solar array, and ultimately to the potential success of the solar electric propulsion solar array shuttle flight experiment program.
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: The 15th Aerospace Mech. Symp.; p 115-136
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  • 14
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    Propagation data bases (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: Existing data bases accumulated as the result of experiments to gather propagation data on millimeter wave Earth-space links are described. The satellites used are described and results of the significant experiments conducted in the United States are summarized. The data bases consist primarily of cumulative attenuation statistics, though some depolarization measurements are included. Additional summaries of propagation data are cited.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Its Propagation Effects Handbook for Satellite Systems Design; p 155-194
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  • 15
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    An overview of several rain and attenuation models (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: The key features of the Rice-Holmberg, Dutton-Dougherty, Global, Lin, and Piecewise Uniform Rain Rate models for estimation of cumulative attenuation statistics on Earth-space millimeter paths are summarized. The models provide either rain rate statistics or attenuation statistics, which can be related by use of the specific attenuation and the effective path length relation. The effective path length is defined. The advantages and disadvantages of each model for specific applications are discussed. The Global model is recommended as the design tool for predicting propagation effects in Earth-space communication systems.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Propagation Effects Handbook for Satellite Systems Design; p 41-101
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  • 16
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    Application of propagation predictions to Earth/space telecommunications system design (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: The corresponding between a given propagation phenomenon and system performance is considered. Propagation data are related to system performance parameters, allowing the systems engineer to perform the analyses determining how well requirements are met by a given system design, and enabling the systems engineer to modify that design if necessary. The various ways of specifying performance criteria for different kinds of systems are discussed, and a general procedure for system design is presented and demonstrated.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Propagation Effects Handbook for Satellite Systems Design; p 349-404
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  • 17
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    Depolarization on Earth-space paths (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: Sources of depolarization effects on the propagation paths of orthogonally-polarized information channels are considered. The main sources of depolarization at millimeter wave frequencies are hydrometeor absorption and scattering in the troposphere. Terms are defined. Mathematical formulations for the effects of the propagation medium characteristics and antenna performance on signals in dual polarization Earth-space links are presented. Techniques for modeling rain and ice depolarization are discussed.
    Keywords: COMMUNICATIONS AND RADAR
    Type: Propagation Effects Handbook for Satellite Systems Design; p 103-154
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  • 18
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    Comparisons of global ozone trends inferred from the BUV experiment on Nimbus 4 and the ground-based network (1981)
    In:  CASI
    Details
    Publication Date: 2006-03-27
    Description: Preliminary comparisons between global ozone burdens derived from the backscattered ultraviolet (BUV) experiment on Nimbus 4 and those inferred from an analysis of ground-based network data seem to indicate significant differences in the inter-annual variability of ozone. Some of the observed differences may be due to improper weighting of the ground-based network data, slowly changing planetary wave structure over the fixed station, of small inter-annual changes in meridional transport parameters. There is also some evidence which indicates that the polar stratosphere at high latitudes may represent an important ozone storage resevoir which tends to compensate for large scale changes observed in the regions outside of the polar stratosphere. Possible consequences of this are that the global trends derived from ground based ozone measurements may not be valid and furthermore that the current satellite techniques by themselves may be sufficient. An ozone monitoring system which includes observations from satellites, ground-based stations, balloons and rockets may be necessary.
    Keywords: GEOPHYSICS
    Type: Goddard Lab. for Atmospheric Sci., Collected Reprints, 1978 - 1979, Vol. 1; p 279
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  • 19
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    An analytic solution to the classical two-body problem with drag (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: The two body problem was analyzed with a specific drag model. The model treats drag as a force proportional to the vector velocity and inversely proportional to the distance to the center of attraction. The solution is expressed in terms of known functions and is of a simple and compact form. The time of flight is expressed as a quadrature in the true anomaly. The results are: (1) development of a vector differential equation which allows analysis of an infinite number of gravitational and drag models; and (2) obtaining the solution of a linear differential equation using the inverse method of laplace transforms.
    Keywords: AERODYNAMICS
    Type: Houston Univ. The 1981 NASA ASEE Summer Fac. Fellowship Program, Vol. 2; 22 p
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  • 20
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    Langley high-lift research on a high-aspect-ratio supercritical wing configuration (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: To determine the low speed performance characteristics of a representative high aspect ratio supercritical wing, two low speed jet transport models were fabricated. A 12-ft. span model was used for low Reynolds number tests in the Langley 4- by 7-Meter Tunnel and the second, a 7.5-ft. span model, was used for high Reynolds number tests in the Ames 12-foot Pressure Tunnel. A brief summary of the results of the tests of these two models is presented and comparisons are made between the data obtained on these two models and other similar models. Follow-on two and three dimensional research efforts related to the EET high-lift configurations are also presented and discussed.
    Keywords: AERODYNAMICS
    Type: Advan. Aerodyn.: Selected NASA Res.; p 55-77
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  • 21
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    Measured transonic unsteady pressures on an energy efficient transport wing with oscillating control surfaces (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: Highlight results are presented from subsonic and transonic pressure measurement studies conducted in the Langley Transonic Dynamics Tunnel on a supercritical wing model representative of an energy efficient transport design. Steady- and unsteady-pressure data were acquired on the upper and lower wing surface at an off-design Mach number of 0.60 and at the design Mach number of 0.78, for a Reynolds number of 2.2 x 10(6) (based on the wing average chord). The model configuration consisted of a sidewall-Mounted half-body fuselage and a semi-span wing with an aspect ratio of 10.76, a leading-edge sweepback angle of 28.8 degrees, and supercritical airfoil sections. The wing is instrumented with 252 static pressure orifices and 164 dynamic pressure gages. Model test variables included wing angle of attack, control-surface mean deflection angle, control-surface oscillating deflection angle and frequency, and phasing between oscillating leading-edge and trailing-edge controls when used together.
    Keywords: AERODYNAMICS
    Type: Advan. Aerodyn.: Selected NASA Res.; p 21-36
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  • 22
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    Measurement of trace levels of chlorine in the stratosphere (1981)
    In:  CASI
    Details
    Publication Date: 2006-02-14
    Description: Mathematical models of stratospheric ozone have predicted a reduction in the total ozone due to chlorofluoromethanes released into the atmosphere. Analytical procedures for the collection of air in the stratosphere and for analysis of these air samples for trace levels of chlorine, regardless of the state of chemical composition were developed. Calibration experiments are conducted in order to validate all methods and procedures. Results of neutron activation analysis calibration procedures using standard chlorine gases are included.
    Keywords: GEOPHYSICS
    Type: Houston Univ. The 1981 NASA ASEE Summer Fac. Fellowship Program, Vol. 2; 15 p
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  • 23
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    Viscous wing code development: A 3-D viscid-inviscid interactive analysis (1983)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: AERODYNAMICS
    Type: NASA. Langley Research Center, Theoretical Aerodynamics Contractors' Workshop, Volume 2; p 607-63
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  • 24
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    Computation of separated flow on airfoils with the Grumfoil code (1983)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: AERODYNAMICS
    Type: NASA. Langley Research Center, Theoretical Aerodynamics Contractors' Workshop, Volume 2; p 557-58
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  • 25
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    Analysis of airfoil transitional separation bubbles (1983)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: AERODYNAMICS
    Type: NASA. Langley Research Center, Theoretical Aerodynamics Contractors' Workshop, Volume 2; p 539-55
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  • 26
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    Entropy effects and shock fitting in conical supersonic full potential flows (1983)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: AERODYNAMICS
    Type: NASA. Langley Research Center, Theoretical Aerodynamics Contractors' Workshop, Volume 2; p 461-49
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  • 27
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    Atmospheric attenuation for correlated satellite communication ground sites (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Link margin estimates are calculated for 30/20 GHz satellite communication systems employing closely-spaced (4 to 100 km) 'dual diversity' switched ground sites. The link margin estimates are based on a new analysis in which the bivariate rain attenuation density function for two correlated ground sites is modelled by an exponential density function. The results of the exponential density function analysis enable derivation of a direct relation between rain margin estimates and probability of exceedance (link availability). Margins typically in the range 2 to 12 dB are calculated for various ground site separations and summarized for seven city locations and five satellite orbit positions over the U.S. The results can be easily extended to other EHF satellite frequencies and other locations.
    Keywords: COMMUNICATIONS AND RADAR
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  • 28
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    Effects of ISI and satellite channel nonlinearity on Viterbi demodulation/decoding (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: It is shown that, for convolutionally coded transmission over bandwidth-constrained channels, a mere reversal of the switching direction at the encoder output produces a change in the system bit error probability performance. This change is significant when the Viterbi demodulator/decoder is matched to the total channel memory and is more significant for linear channels than for nonlinear ones. The reversal of switching direction is a simple demonstration of the fact that the well-known optimum codes for the linear AGWN channel are no longer necessarily optimum for a bandwidth-constrained channel with or without the addition of channel nonlinearity. It is concluded that potentially significant performance improvement can be obtained by matching the encoder (through the appropriate choice of tap weights and modulo-2 summers) to the channel in addition to matching the demodulator/decoder to the channel for a given encoder.
    Keywords: COMMUNICATIONS AND RADAR
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  • 29
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    GRM - Observing the terrestrial gravity and magnetic fields in the 1990's (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: NASA is proposing to launch a new geopotential fields exploration system called the Geopotential Research Mission (GRM). Two spacecraft will be placed in a circular polar orbit at 160 km altitude. Distances between these satellites will vary from 100 to 600 km. Both scalar and vector magnetic fields will be measured by magnetometers mounted on a boom positioned in the forward direction on the lead satellite. Gravity data will be computed from the measured change in distance between the two spacecraft. This quantity, called the range-rate, will be determined from the varying frequency (Doppler shift) between transmitter and receiver on each satellite. Expected accuracies (at the one-sigma level) are: gravity field, 1.0 milliGal, 5 cm geoid height; magnetics, scalar field 2 nT, vector to 20 arcsec, both resolved to less than 100 km. With these more accurate and higher resolution data, it will be possible to investigate the earth's structure from the crust (with the shorter wavelength gravity and magnetic anomalies) through the mantle (from the intermediate wavelength gravity field) and into the core (using the longer wavelength gravity and magnetic fields).
    Keywords: GEOPHYSICS
    Type: EOS (ISSN 0096-3941); 64; 609-611
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  • 30
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    Photovoltaic conversion of laser to electrical power (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Transmission of power in space using lasers will require devices for converting the laser power to electrical power. One such type of device for accomplishing this is the photovoltaic converter. This paper reviews photovoltaic converters and their application for conversion of monochromatic laser power to electrical power. Laser power densities greater than 1000 W/sq cm are considered. For a converter operated at 300 K a lower bandgap limit of 0.67 eV (1.80 micron) is defined. For ideal conditions, an efficiency of 47.8 percent is calculated for Nd/Liquid laser radiation incident on an Si converter. Several types of photovoltaic converters are discussed. Series resistance is identified as a major problem. Vertical multijunction converters are the most promising photovoltaic devices for use as laser to electric power converters.
    Keywords: SPACECRAFT PROPULSION AND POWER
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  • 31
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    Space power system utilizing Fresnel lenses for solar power and also thermal energy storage (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: A solar power plant suitable for earth orbits passing through Van Allen radiation belts is described. The solar-to-electricity conversion efficiency is estimated to be around 9 percent, and the expected power-to-weight ratio is competitive with photovoltaic arrays. The system is designed to be self-contained, to be indifferent to radiation belt exposures, store energy for periods when the orbiting system is in earth shadow (so that power generation is contant), have no moving parts and no working fluids, and be robust against micrometeorite attack. No electrical batteries are required.
    Keywords: SPACECRAFT PROPULSION AND POWER
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  • 32
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    Development of a rotary power transformer and inverter drive for spacecraft (1983)
    In:  Other Sources
    Details
    Publication Date: 2011-08-18
    Description: Many future satellites and spacecraft with spun and despun configurations will require the transfer of power across rotating interfaces in lieu of slip-rings and/or flexures. This is particularly true of spacecraft that have to demonstrate a long life expectancy. The rotary transformer has the desirable characteristics of high reliability and low noise, which qualify it as a potential replacement for slip rings. Development of a rotary power transformer follows the successful completion of a task to develop rotary signal-level transformers for the Galileo Spacecraft Project. The physical configuration of a rotary power transformer has a significant effect on its magnetic and electrical characteristics and therefore impacts the design of the dc/ac inverter driver. Important characteristics addressed during this development effort include: operating frequency, efficiency, transformer gap size, leakage inductance, and leakage flux. A breadboard inverter and rotary transformer were designed, fabricated and tested.
    Keywords: SPACECRAFT PROPULSION AND POWER
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    Measurements of stratospheric SO2 after the EL Chichon eruptions (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Samples of stratospheric trace gases were obtained on eight flights of NASA high-altitude aircraft from April 16 through December 13, 1982. The sampling occurred at altitudes from 15 to 22 km, latitudes from 23 to 52 deg N, and longitudes from 108 to 130 deg W. The cryogenically concentrated samples were analyzed by gas chromatography for SO2, a primary precursor of the gas-to-particle conversion process. The measured mixing ratio of SO2 varied between 8 and 132 pptv. Evidence from aerosol measurements indicates that a few of our early samples may have been collected in the fringes of the volcanic cloud from El Chichon. Samples obtained on some later flights may have been from the eruption cloud but were taken at times when most of the volcanically injected SO2 should have been converted to H2SO4.
    Keywords: GEOPHYSICS
    Type: Geophysical Research Letters (ISSN 0094-8276); 10; 1045-104
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    Effect of the eruption of El Chichon stratospheric aerosol size and composition (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Dominant effects of the El Chichon eruption on stratospheric aerosols at 19.8 to 20.7 km are: (1) vapor depositional growth of the small-aerosol (background) mode; (2) development of a large-particle mode by sedimentation from the highest altitudes in the cloud; (3) a change in the large-particle mode from sulfate-coated silicates to sulfate aerosols, some with silicate cores; (4) a 100-fold increase in sulfate mass in the large particle mode. Terminal velocities of large silicate particles, maximum r = 2.3 micron, sampled 1 month after eruption, and calibrated with the aid of lidar data, indicate initial injection to 26 to 27 km. Smaller velocities of sulfate aerosols, median r = 0.5 micron, are compatible with major growth in 2 to 3 months at 27 to 28 km. Aerosol settling accounts for the descent of the main lidar return to 26.5 km in August and to 20 to 21 km in December.
    Keywords: GEOPHYSICS
    Type: Geophysical Research Letters (ISSN 0094-8276); 10; 1021-102
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  • 35
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    Possible effects of the El Chichon volcanic cloud on the radiation budget of the northern tropics (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: A series of calculations with a one-dimensional, time-marching, radiative-convective model are performed to assess the impact of the El Chichon volcanic cloud on the radiation budget of the northern tropics during the 6-month period following the injection of volcanic material into the stratosphere. Extensive measurement of the cloud obtained from airborne, spacecraft, and ground platforms were used to define the model parameters and to test the predictions of the model. The El Chichon cloud is predicted to have caused an increase in planetary albedo of 10 percent, a decrease in total solar radiation of 2-3 percent at the ground on cloudless days, and an increase in temperature of 3.5 K at the 24-km (30-mb) level. These predictions are compatible with relevant observations, within their respective error bars.
    Keywords: GEOPHYSICS
    Type: Geophysical Research Letters (ISSN 0094-8276); 10; 1057-106
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  • 36
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    A revised thermospheric model based on mass spectrometer and incoherent scatter data - MSIS-83 (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: It is noted that the model presented here extends the previous description of neutral parameters to the base of the thermosphere in a continuous manner while maintaining the basic structure of the MSIS model at higher altitudes. As the altitude decreases, the composition approaches lower atmosphere values, whereas yearly, and to a lesser extent daily, variations in temperature and density are in reasonable agreement with earlier results for the lower thermosphere. An alternate description is given of magnetic storm variations on the basis of the three hour ap indices and an 8- to 10-hour exponential decay in thermospheric density and temperature response after a heating event. Additional coefficients are included for the time independent and magnetic activity terms, among them a longitudinally dependent seasonal magnetic activity effect. The description of molecular oxygen derives from mass spectrometer and EUV absorption measurements rather than ion chemistry.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 10170-10
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  • 37
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    Response of the mobile VLBI design to error sources (1983)
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    Publication Date: 2011-08-18
    Description: The response of Mobile VLBI design to error sources is addressed. The sensitivity of the hydrogen maser to variations in ambient temperature is discussed, with an example of drifts in the frequency system causing excursions in the time-delay observable exceeding + or - 200 cm. It is shown that baselines determined only from S-band data can contain errors in excess of 30 cm during periods of high ionospheric activity. The effect of the troposphere on baseline solutions is examined by comparing calibrations from the Water Vapor Radiometer (WVR) to those from a surface model. The apparent ability of the WVR to track relatively short-period fluctuations in water vapor is noted. Finally, consideration is given to the effects of source structure and the technique of monitoring closure of the time-delay observable around a closed figure of baselines.
    Keywords: GEOPHYSICS
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  • 38
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    An exploratory study of area-efficient vortex flap concepts (1983)
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    Publication Date: 2011-08-18
    Description: The potential of planform modification and hinge-line relocation to improve the thrust efficiency of vortex flaps was experimentally investigated on a 60-deg cropped delta wing model. Spanwise segmentation of the flap, together with chord-tailoring of the segments, allowed the vortex to be maintained on the outboard flap surfaces to higher angles of attack. In addition, location of the flap hinge aft of and underneath the wing leading edge generated substantial thrust from the vortex suction acting on the leading-edge lower surface. A combination of these beneficial effects allowed the flap/wing area to be reduced from 11.4 percent of the continuous flap to 6.3 percent of segmented flap, essentially without detriment to the incremental lift-to-drag ratio due to flap addition in the lift coefficient range 0.5-0.7 based on the basic wing area.
    Keywords: AERODYNAMICS
    Type: Journal of Aircraft (ISSN 0021-8669); 20; 1062-106
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  • 39
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    Observations and implications of natural laminar flow on practical airplane surfaces (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Previously cited in issue 20, p. 3138, Accession no. A82-40893
    Keywords: AERODYNAMICS
    Type: Journal of Aircraft (ISSN 0021-8669); 20; 993-1006
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  • 40
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    Stratospheric condensation nuclei and possible solar influences (1983)
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    Publication Date: 2011-08-18
    Description: Balloon-borne measurements of condensation nuclei and H2SO4 molecules in large negative ion clusters have been made in the stratosphere at around 30 km altitude. The nuclei observed were in the 0.01-0.1 micron diameter range. Consideration was given to sunspot activity as a triggering event for ionization of upper atmospheric H2SO4 species and subsequent formation of the nuclei. A numerical model was defined for a steady state between the H2SO4 association and ion recombination in order to determine a critical nucleation rate. It is concluded that condensation nuclei are produced in ion nucleation in an H2SO4 supersaturated polar cloud chamber, with the process being initiated by solar flare particle ionization.
    Keywords: GEOPHYSICS
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  • 41
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    A study of solar activity-ozone relationship from Nimbus-4 BUV data (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: The total O3 and the O3 mixing ratio at various pressure levels in the stratosphere measured from the Nimbus-4 BUV experiment over a 7-yr period (1970 to 1977) comprises a comprehensive data base available to study the possible effects of solar variability on stratospheric O3. It is shown that with the decrease in solar activity from 1970 to 1976, the globally averaged O3 inferred from Nimbus-4 data decreases from about 10 to 12 percent in the upper stratosphere to about 1 to 3 percent in the lower stratosphere. The systematic decrease in O3 seems to be correlated with the conventional indices of solar activity; however, it is difficult to account for the observed changes at various pressure levels with the current understanding of the photochemical models and the solar UV flux variations over a solar cycle.
    Keywords: GEOPHYSICS
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  • 42
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    Delta function excitation of waves in the earth's ionosphere (1983)
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    Publication Date: 2011-08-18
    Description: Excitation of the earth's ionosphere by delta function current sheets is considered, and the temporal and spatial evolution of wave packets is analyzed for a two-component collisional F2 layer. Approximations of an inverse Fourier-Laplace transform via saddle point methods provide plots of typical wave packets. These illustrate cold plasma wave theory and may be used as a diagnostic tool since it is possible to relate specific features, e.g., the frequency of a modulation envelope, to plasma parameters such as the electron cyclotron frequency. It is also possible to deduce the propagation path length and orientation of a remote radio beacon.
    Keywords: GEOPHYSICS
    Type: Radio Science (ISSN 0048-6604); 18; 1337-135
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  • 43
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    Stability of shock waves attached to wedges and cones (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Previously cited in issue 06, p. 799, Accession no. A82-17876
    Keywords: AERODYNAMICS
    Type: AIAA Journal (ISSN 0001-1452); 21; 1611-161
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  • 44
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    Normal mode study of the earth's rigid body motions (1983)
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    Publication Date: 2011-08-18
    Description: In this paper it is shown that the earth's rigid body (rb) motions can be represented by an analytical set of eigensolutions to the equation of motion for elastic-gravitational free oscillations. Thus each degree of freedom in the rb motion is associated with a rb normal mode. Cases of both nonrotating and rotating earth models are studied, and it is shown that the rb modes do incorporate neatly into the earth's system of normal modes of free oscillation. The excitation formula for the rb modes are also obtained, based on normal mode theory. Physical implications of the results are summarized and the fundamental differences between rb modes and seismic modes are emphasized. In particular, it is ascertained that the Chandler wobble, being one of the rb modes belonging to the rotating earth, can be studied using the established theory of normal modes.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 9437-944
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  • 45
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    A mechanism for plasma waves at the harmonics of the plasma frequency in the electron foreshock boundary (1983)
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    Publication Date: 2011-08-18
    Description: A bump-on-tail unstable reduced velocity distribution, constructed from data obtained at the upstream boundary of the electron foreshock by the GSFC electron spectrometer experiment on the ISEE-1 satellite, is used as the initial plasma state for a numerical integration of the 1D-Vlasov-Maxwell system of equations. The integration is carried through the growth of the instability, beyond its saturation, and well into the stabilized plasma regime. A power spectrum computed for the electric field of the stabilized plasma is dominated by a narrow peak at the Bohm-Gross frequency of the unstable field mode but also contains significant power at the harmonics of the Bohm-Gross frequency. The harmonic power is in sharp peaks which are split into closely spaced doublets. The fundamental peak at the Bohm-Gross frequency is split into a closely spaced triplet. The mechanism for excitation of the second harmonic is shown to be second order wave-wave coupling. Previously announced in STAR as N83-17315
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 9081-909
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  • 46
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    Medium scale disturbances in total ozone during Southern Hemisphere summer (1983)
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    Publication Date: 2011-08-18
    Description: Distinct medium scale disturbances in Southern Hemisphere total ozone were observed by the Nimbus 7 Total Ozone Mapping Spectrometer during the 1979 FGGE observing period. These disturbances are shown to be a result of advection by the zonal harmonic wave five which is centered near the tropopause (Salby, 1982). The contribution to the total ozone field by vertical advection due to this wave is shown to be nearly equal to that due to horizontal advection.
    Keywords: GEOPHYSICS
    Type: American Meteorological Society, Bulletin (ISSN 0003-0007); 64; 1358-136
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  • 47
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    Isotopic evidence from the eastern Canadian shield for geochemical discontinuity in the Proterozoic mantle (1983)
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    Publication Date: 2011-08-18
    Description: The Nd and Sr isotopic compositions presently reported for anorthosites and related rocks from the Grenville and Nain Provinces of the eastern Canadian shield indicate that the massifs were delivered from at least two distinct mantle source regions which were established before 1650 Myr ago. These regions were episodically involved in magmatism over about 500 Myr. One reservoir was isotopically similar to the depleted, modern midocean ridge basalt source. The other reservoir was chondritic-to-moderately-enriched, and is most easily identified in the Nain Province, but may have occurred scattered throughout Superior Province, as well.
    Keywords: GEOPHYSICS
    Type: Nature (ISSN 0028-0836); 306; 679
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  • 48
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    Distribution, abundance and carbon isotopic composition of gaseous hydrocarbons in Big Soda Lake, Nevada - An alkaline, meromictic lake (1983)
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    Publication Date: 2011-08-18
    Description: The study of the distribution and isotopic composition of low molecular weight hydrocarbon gases at the Big Soda Lake, Nevada, has shown that while neither ethylene nor propylene were found in the lake, ethane, propane, isobutane and n-butane concentrations all increased with water column depth. It is concluded that methane has a biogenic origin in both the sediments and the anoxic water column, and that C2-C4 alkanes have biogenic origins in the monimolimnion water and shallow sediments. The changes observed in delta C-13/CH4/ and CH4/(C2H6 + C3H8) with depth in the water column and sedimeents are probably due to bacterial processes, which may include anaerobic methane oxidation and different rates of methanogenesis, and C2-to-C4 alkane production by microorganisms.
    Keywords: GEOPHYSICS
    Type: Geochimica et Cosmochimica Acta (ISSN 0016-7037); 47; 2107-211
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  • 49
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    Autoregressive harmonic analysis of the earth's polar motion using homogeneous International Latitude Service data (1983)
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    Publication Date: 2011-08-18
    Description: The homogeneous set of 80-year-long (1900-1979) International Latitude Service (ILS) polar motion data is analyzed using the autoregressive method (Chao and Gilbert, 1980), which resolves and produces estimates for the complex frequency (or frequency and Q) and complex amplitude (or amplitude and phase) of each harmonic component in the data. The ILS data support the multiple-component hypothesis of the Chandler wobble. It is found that the Chandler wobble can be adequately modeled as a linear combination of four (coherent) harmonic components, each of which represents a steady, nearly circular, prograde motion. The four-component Chandler wobble model 'explains' the apparent phase reversal during 1920-1940 and the pre-1950 empirical period-amplitude relation. The annual wobble is shown to be rather stationary over the years both in amplitude and in phase, and no evidence is found to support the large variations reported by earlier investigations. The Markowitz wobble is found to be marginally retrograde and appears to have a complicated behavior which cannot be resolved because of the shortness of the data set.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 10299-10
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    Comparison of Yamato and Victoria Land polymict eucrites - A view from mineralogical and isotopic studies (1983)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: New interior samples of four Yamato polymict eucrites (Y74159, Y74450, Y75011, and Y75015) have been studied by electron microprobe, transmission electron microscope, and X-ray diffraction techniques, and compared with several samples of the Victoria Land polymict eucrites. These same samples have been analysed using Rb-Sr and Nd-Sm isotopic systematics. Several grains of inverted pigeonite, with blebby augite similar to those in Binda and Moama, have been identified in all four Yamato eucrites. Coarse-grained meso-stasis-rich subophitic basalts, which contain Mg-rich pigeonite (with Fe-rich olivine veinlets) zoned outward to a subcalcic ferroaugite rims, have also been found. These unique clasts were not found in ALH76005, 77302, 78040, 7858, and 78165 and EET eucrites. The tight grouping of Rb/Sr and Sm/Nd ratos, and similar modal compositions of the Yamato group indicate that they are most likely to be pieces from a single fall, and distinct from the ALH and EET groups. However, the Yamato, Allan Hills, and Elephant Moraine groups may sample a few distinct magmas or similar but different source regions on the same parent body.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research, Supplement (ISSN 0148-0227); 88; B245-B25
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    SERIES - Satellite Emission Range Inferred Earth Surveying (1983)
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    Publication Date: 2011-08-18
    Description: The Satellite Emission Range Inferred Earth Surveying (SERIES) concept is based on the utilization of NAVSTAR Global Positioning System (GPS) radio transmissions without any satellite modifications and in a totally passive mode. The SERIES stations are equipped with lightweight 1.5 m diameter dish antennas mounted on trailers. A series baseline measurement accuracy demonstration is considered, taking into account a 100 meter baseline estimation from approximately one hour of differential Doppler data. It is planned to conduct the next phase of experiments on a 150 m baseline. Attention is given to details regarding future baseline measurement accuracy demonstrations, aspects of ionospheric calibration in connection with subdecimeter baseline accuracy requirements of geodesy, and advantages related to the use of the differential Doppler or pseudoranging mode.
    Keywords: GEOPHYSICS
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    Calculated stormtime variations in plasmaspheric thermal ion composition (1983)
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    Publication Date: 2011-08-18
    Description: Model calculations describing stormtime variations in the earth's dayside plasmasphere are used to examine variations in ion composition. The model storm is initiated by high-latitude thermospheric heating that generates meridional winds that carry neutral species, momentum, and energy equatorward. The thermosphere acts on the plasmasphere through collisional transfer of momentum and through chemical reactions between neutral species and ions. Over latitudes near the region of thermospheric heating, the thermosphere-plasmasphere coupling processes cause enhancement in the density of oxygen ions while protons are being lost. Meanwhile, densities of oxygen ions and protons near the equator are increasing together, almost in phase. The largest enhancements in ion density develop at latitudes near 45 deg invariant for both oxygen and hydrogen.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 10233-10
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  • 53
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    A chimera grid scheme (1983)
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    Publication Date: 2011-08-18
    Description: A mesh system composed of multiple overset body-conforming grids is described for adapting finite-difference procedures to complex aircraft configurations. In this so-called 'chimera mesh,' a major grid is generated about a main component of the configuration and overset minor grids are used to resolve all other features. Methods for connecting overset multiple grids and modifications of flow-simulation algorithms are discussed. Computational tests in two dimensions indicate that the use of multiple overset grids can simplify the task of grid generation without an adverse effect on flow-field algorithms and computer code complexity.
    Keywords: AERODYNAMICS
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  • 54
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    Differential versus limiter-discriminator detection of narrow-band FM (1983)
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    Publication Date: 2011-08-18
    Description: The error probability performance of differential detection of narrow-band FM is determined and compared with the analogous results for limiter-discriminator detection of the same modulation. It is shown that over a large class of benign and hostile environments, e.g., Gaussian IF filter, AWGN, partial-band noise jamming, the differential detector offers no theoretical performance advantage over the limiter-discriminator receiver with integrate-and-dump postdetection filtering.
    Keywords: COMMUNICATIONS AND RADAR
    Type: IEEE Transactions on Communications (ISSN 0090-6778); COM-31; 1227-123
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  • 55
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    A model study of the effects of intermittent loss on odd nitrogen concentrations in the lower troposphere (1983)
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    Publication Date: 2011-08-18
    Description: A time-dependent box model of the lower troposphere which includes a description of photochemical and physical processes has been developed. This model has been applied to the calculation of nitric acid and NO(x)(NO + NO2) concentrations over a diurnal cycle which includes precipitation. Nitric acid concentrations and the HNO3/NO(x) ratio are found to be highly variable under the assumptions regarding the frequency, duration, and intensity of precipitation employed in this model. The chemistry of odd nitrogen compounds during the night is potentially important in establishing the level of nitric acid in the lower troposphere. These calculations also indicate that relatively large errors may occur when the continuity equation describing nitric acid variations is averaged over a diurnal cycle which includes precipitation. Interpretation of simultaneous measurements of HNO3 and NO(x) will require some knowledge of the history of the observed air mass and may require an improved understanding of nighttime odd nitrogen chemistry.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 10697-10
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  • 56
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    Observation of wave-wave interactions in the stratosphere (1983)
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    Publication Date: 2011-08-18
    Description: Data from the LIMS instrument for January 1979 are used to provide further evidence for the often observed vacillation between the amplitudes of waves 1 and 2 in the stratosphere. The vacillation is shown to result primarily from nonlinear wave-wave interactions within the stratosphere. Two ways of interpreting nonlinearity are discussed. In the first, the basic state is defined to include large amplitude waves as well as the mean zonal wind. A forced wave propagates with respect to this asymmetric basic state, which can lead to changes in the conventional zonal wavenumber measured at one latitude. The other view of nonlinearity, interaction of wave with the zonal flow and with other wavenumbers are considered separately. Wave-wave interactions among waves 1, 2 and 3 are calculated. The derivation and computation of wave-wave interaction terms in the potential enstrophy balance are given. The observations indicate that enstrophy transfer among waves can be substantial even when the amplitude of one of the contributing waves is small. The computed enstrophy balance also demonstrates that wave-wave interactions can have a large effect on the interaction of waves with the mean flow.
    Keywords: GEOPHYSICS
    Type: Journal of the Atmospheric Sciences (ISSN 0022-4928); 40; 2484-249
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    Experimental and systems studies of the alkali metal thermoelectric converter for aerospace power (1983)
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    Publication Date: 2011-08-18
    Description: Previously cited in issue 15, p. 2361, Accession no. A82-31876
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: Journal of Energy (ISSN 0146-0412); 7; 442-448
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  • 58
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    Stratospheric temperature profile from balloon-borne measurements of the 10.4-micron band of CO2 (1983)
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    Publication Date: 2011-08-18
    Description: The technique of nonlinear least squares spectral curve fitting has been used to derive the stratospheric vertical temperature profile from balloon-borne measurements of the 10.4 micron band of CO2. The spectral data were obtained at sunset with the approximately 0.02 per cm resolution University of Denver interferometer system from a float altitude of 33.5 km near Alamogordo, New Mexico, on 23 March 1981. The r.m.s. deviation between the retrieved temperature profile and correlative radiosonde measurements is 2.2 K.
    Keywords: GEOPHYSICS
    Type: Journal of Quantitative Spectroscopy and Radiative Transfer (ISSN 0022-4073); 30; 327-334
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  • 59
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    Conservative full-potential calculations for axisymmetric, transonic flow (1983)
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    Publication Date: 2011-08-18
    Description: Previously cited in issue 17, p. 2873, Accession no. A81-38082
    Keywords: AERODYNAMICS
    Type: AIAA Journal (ISSN 0001-1452); 21; 1492-149
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  • 60
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    Electric field measurements at the magnetopause. I Observation of large convective velocities at rotational magnetopause discontinuities (1983)
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    Publication Date: 2011-08-18
    Description: Large convective electric fields of the order of 10 mV/m (sometimes as high as 22 mV/m) are observed at rotational magnetopause discontinuities. These observations were made with the long cylindrical (179-m base line) probes carried on the ISEE 1 satellite. These electric field observations yield convective velocity magnitudes (equal to the cross product of the vector E and the vector B, the latter divided by the square of the magnitude of B) of the order of 150 km/s. In this format for the convective velocity magnitudes, some of these observations are similar to the high speed plasma velocity observations that were made at the magnetopause with the plasma experiment carried on the ISEE 1 satellite. It is shown that, for many of these magnetopause crossings, there exists a special moving coordinate system where the observed electric fields vanish. Such a unique reference system is often used in theoretical studies of magnetic discontinuities. This special coordinate system does not move at the local plasma velocity but moves instead at a velocity intermediate between the convective velocity and the local Alfven velocity. It is used here as a diagnostic tool for the experimental investigation of rotational discontinuities at the magnetopause.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research (ISSN 0148-0227); 88; 10000-10
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  • 61
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    Plume radiation heat transfer: Radiation transfer with scattering (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 13 p
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  • 62
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    Plume radiation heat transfer: Prediction techniques with scattering (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 19 p
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  • 63
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    Plume radiation heat transfer: Spatial integration procedures (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 19 p
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  • 64
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    Plume radiation heat transfer: Spectrally averaged parameters (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 11 p
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  • 65
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    Plume radiation heat transfer: Band models (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 22 p
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  • 66
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    Plume radiation heat transfer: Fundamentals (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 15 p
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  • 67
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    Plume radiation heat transfer (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 5 p
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  • 68
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    Base flow simulation: Hot flow simulation for base heating analysis (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 16 p
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  • 69
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    Base flow simulation (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 5 p
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  • 70
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    Base flow simulation: Cold flow simulation for base pressure analysis (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 21 p
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  • 71
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    Plume backflow in a vacuum: Impingement environments (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 13 p
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  • 72
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    Plume backflow in a vacuum: Impingement flowfields (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 6 p
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  • 73
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    Plume backflow in a vacuum: Free molecular plumes (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 4 p
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  • 74
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    Plume backflow in a vacuum: Onset of rarefaction (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 7 p
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  • 75
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    Plume backflow in a vacuum: Viscous - inviscid coupling (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 10 p
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  • 76
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    Plume backflow in a vacuum: Continuumm plume (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 16 p
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  • 77
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    Multiple engines: Non-symmetrical engine arrangements (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 25 p
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  • 78
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    Plume backflow in a vacuum: Nozzle boundary layers (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 7 p
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  • 79
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    Multiple engines: Dual engines (in-line multiple engines) (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 33 p
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  • 80
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    Multiple engines: Symmetrical engine arrangements (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 100 p
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  • 81
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    Multiple engines (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 13 p
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  • 82
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    Single engine (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 109 p
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  • 83
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    Single engine: Plume induced flow separation (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 39 p
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  • 84
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    Recommended procedure for selecting methodology (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 12 p
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  • 85
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    Methodology selection plan (1981)
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 13 p
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  • 86
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    Historical development of base flow predictive methods (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 19 p
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  • 87
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    JANNAF Handbook: Rocket Exhaust Plume Technology. Chapter 5: Base flow. Problem definition (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 27 p
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  • 88
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    JANNAFF Handbook: Rocket Exhaust Plume Technology. Chapter 5: Base flow. Nomenclature (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAFF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 5 p
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  • 89
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    JANNAF Handbook: Rocket exhaust plume technology. Chapter 5: Base flow. Introduction (1981)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Keywords: SPACECRAFT PROPULSION AND POWER
    Type: JANNAFF Handbook: Rocket Exhaust Plume Technol., Chapter 5; 5 p
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  • 90
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    Estimation of lower crust magnetization form satellite derived anomaly field (1983)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Description: Various lines of evidence point to the lower crust as the source of the long-wavelength magnetic anomaly field measured by the POGO and Magsat satellites. Using seismically determined lower crust thicknesses and equivalent source inversion of the satellite anomaly data, magnetization for the lower crust for much of the United States has been calculated. The average magnetization for two hundred sixty-six 150 x 150 km areas is 3.5 A/m with a standard deviation of 1.1 A/m. These values are consistent with laboratory measurements of mafic-ultramafic rocks expected in the lower crust, and in agreement with previous estimates of lower crust magnetization based on long-wavelength aeromagnetic data. Average lower crust thickness for the same areas is 18.2 km (sigma = 6.4). Thus, over large regions, it appears that variation in magnetization and variation in magnetic layer thickness contribute almost equally in causing the anomaly field variation at satellite altitude.
    Keywords: GEOPHYSICS
    Type: Tectonophysics (ISSN 0040-1951); 93; 33-45
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  • 91
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    Cold plasma distribution above a few thousand kilometers at high latitudes (1983)
    In:  Other Sources
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    Publication Date: 2011-08-19
    Description: Great advances with respect to the study of the earth's magnetosphere could be achieved in connection with the launch of the Dynamics Explorer (DE) 1 and 2 spacecraft. These advances were made possible partly because of the unique combination of coplanar orbits which simultaneously sample the low altitude ionospheric and atmospheric signature (DE-2) and the high altitude phenomena of the inner magnetosphere (DE-1). It was, thus, feasible to obtain new measurements of the coupling of plasmas and fields between these fundamentally important regions. One basic element of the coupling involves the interchange of low energy plasma between the ionosphere and magnetosphere. The flow characteristics of the low energy plasma are indicators of the magnetospheric and ionospheric electric fields which drive the current system. The Retarding Ion Mass Spectrometer (RIMS) instrument has been designed for conducting measurements regarding this plasma population. Attention is given to details regarding RIMS, an example RIMS orbit, plasma trough characteristics, and polar cap phenomena.
    Keywords: GEOPHYSICS
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  • 92
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    Atmospheric density, temperature and wind measurement techniques during the 1980 Energy Budget Campaign (1981)
    In:  CASI
    Details
    Publication Date: 2011-12-30
    Description: Super Loki rocketsonde systems are described. The datasonde telemeters data to a ground station where ambient temperatures are calculated between 20 and 70 km. The sphere is a passive, radar tracked system which allows density to be calculated between 30 and 90 km. When flown simultaneously the systems give redundant data in the altitudes between 30 and 70 km. The datasonde has a balloon parachute that descends more slowly than a conventional parachute and is more stable. Because of launch constraints the datasondes reached very high apogees, leading to very fast descent velocities. Aerodynamic heating reduced thermistor sensitivity. Anomalous parachute behavior influenced wind sensing until a denser layer was reached. The spheres collapsed above 60 km altitude, but their data, combined with dropsonde data give significant results for 21 flights. These show that the stratosphere is colder than Cospar 72 model predictions and the mesosphere is warmer.
    Keywords: GEOPHYSICS
    Type: Wuppertal Univ. Sounding Rocket Program Aeronomy Project: Energy Budget Campaign 1980. Expt. Summary; p 382-396
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  • 93
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    Radiative-photochemical response of the mesosphere to dynamical forcing (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Combination of the chemical continuity equation for odd oxygen with the second law of thermodynamics yields analytic solutions which describe the coupled behavior of temperature and ozone perturbations in response to an externally specified forcing. The results appear in a form which allows easy physical interpretation of the coupling between radiative and photochemical processes. When the forcing is chosen to mimic a planetary scale wave, the theory shows that photochemical acceleration of radiative damping reduces the amplitude of the temperature perturbation by an amount which increases with the wave period. Although ozone fluctuations are anti-correlated with those in temperature, minima in ozone do not coincide exactly in longitude with temperature maxima. The percentage variation in ozone increases upward and is always larger than that in temperature at the same pressure. This demonstrates that variations in ozone on constant pressure surfaces may serve as a sensitive indicator of wave activity in the mesosphere.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 86; June 20
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  • 94
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    Particles above the tropopause - Measurements and models of stratospheric aerosols, meteoric debris, nacreous clouds, and noctilucent clouds (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: An outline is presented of the present status of knowledge of stratospheric aerosols, meteoric debris, nacreous clouds, and noctilucent clouds. Considerable progress has been made in studies of these particles during the previous decade and it is appropriate to synthesize the information to provide a background for studies planned for the 1980s. Numerical models of the formation, growth, and evolution are considered and a description is given of the physical processes involved, taking into account aspects of nucleation, coagulation, condensational growth, sedimentation, and questions of dynamical transport. A schematic outline of the physical and chemical processes included in a model of stratospheric aerosols is provided.
    Keywords: GEOPHYSICS
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  • 95
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    The CAMEO barium release - E/parallel/ fields over the polar cap (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Four successive thermite barium releases at an altitude of 965 km over polar cap invariant latitudes 84 to 76 deg near magnetic midnight were conducted from the orbiting second stage of the vehicle that launched Nimbus 7; the releases were made as part of the CAMEO (Chemically Active Material Ejected in Orbit) program. This was the first opportunity to observe the behavior of conventional barium release when conducted at orbital velocity in the near-earth magnetic field. The principal unexpected characteristic in the release dynamics was the high, 1.4 to 2.6 km/s, initial Ba(+) expansion velocity relative to an expected velocity of 0.9 km/s. Attention is also given to neutral cloud expansion, initial ion cloud expansion, convective motion, and the characteristics of field-aligned motion. The possibility of measuring parallel electric fields over the polar cap by observing perturbations in the motion of the visible ions is assessed.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 86; May 1
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  • 96
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    Very low frequency waves stimulated by an electron accelerator in the auroral ionosphere (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: The sounding rocket, Polar 5, carrying a 10 keV electron accelerator in a mother-daughter configuration and other diagnostic instruments, was launched into a slightly disturbed ionosphere with weak auroral activity on February 1, 1976 from Northern Norway to study VLF wave phenomena. The rocket trajectory crossed two auroral regions: one, between 86 and 111 s flight time, and a secondary region between 230 and 330 s. The daughter, carrying the accelerator, was separated axially from the mother in a forward direction at an altitude of 90 km. The VLF experiment, carried by the mother payload, recorded both electromagnetic and electrostatic waves. The receiving antenna was an electric dipole, 0.3 m tip-to-tip, oriented 90 degrees to the rocket spin axis. The onboard particle detector recorded increased electron fluxes in the two auroral regions. A double peaked structure was observed in the fluxes of 4-5 and 12-27 keV electrons within the northern auroral form. The number density of thermal plasma varied during the flight, with maximum density within the main auroral region. To the north of this aurora a slow, steady decrease in the density was observed, with no enhancement in the region of the second aurora.
    Keywords: GEOPHYSICS
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    An analytic formulation for heating source memory in the thermospheric composition (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Numerical calculations from a spectral circulation model are utilized to construct an analytic Green's function formulation describing the meridional, time-dependent thermospheric composition and temperature response during magnetic storms. The purpose is to develop a formulation that embodies source memory while being sufficiently simple to serve as a heuristic guide for empirical modeling. By passing from the discrete Fourier series representation, utilized for the numerical circulation model, to a continuous Fourier integral representation, explicit waves are obtained for the thermospheric response times. The response times are altitude and species dependent and can exceed two days below 200 km. Thus, for certain storm scenarios, pronounced source memory signatures for the composition and temperature are predicted. Response times obtained from the formulation are shown to give a response consistent with previously published neutral composition data from AE-C for the February 1974 storm when an ap dependent heat source is employed.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 86; May 1
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  • 98
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    Semiempirical modeling of thermospheric magnetic storms (1981)
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    Publication Date: 2011-08-18
    Description: An improved formulation for empirical modeling of magnetic storm effects in neutral thermospheric composition and temperature is utilized in a study of two disturbed periods. The formulation, which incorporates the prior history of the heat input rather than a single phase delay, is based on a Fourier integral representation of an existing theoretical model. This results in an improved representation of the detailed time variations and a better carry-over of model parameters from one storm to the other and provides a basis for theoretical interpretation.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 86; May 1
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  • 99
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    Inference of the ring current ion composition by means of charge exchange decay (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: The analysis of data from the Explorer 45 (S3-A) electrostatic analyzer in the energy range 5-30 keV has provided some new results on the ring current ion composition. It has been well established that the storm time ring current has a decay time of several days, during which the particle fluxes decrease nearly monotonically. By analyzing the measured ion fluxes during the several day storm recovery period and assuming that beside hydrogen other ions were present and that the decays were exponential in nature, three separate lifetimes for the ions were established. These fitted decay lifetimes are in excellent agreement with the expected charge exchange decay lifetimes for H(+), O(+) and He(+) in the energy and L value range of the data.
    Keywords: GEOPHYSICS
    Type: Journal of Geophysical Research; 86; May 1
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  • 100
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    Vortex-flow aerodynamics - An emerging design capability (1981)
    In:  Other Sources
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    Publication Date: 2011-08-18
    Description: Promising current theoretical and simulational developments in the field of leading edge vortex-generating delta, arrow ogival wings are reported, along with the history of theory and experiment leading to them. The effects of wing slenderness, leading edge nose radius, Mach number and incidence variations, and planform on the onset of vortex generation and redistribution of aerodynamic loads are considered. The range of design possibilities in this field are consequential for the future development of strategic aircraft, supersonic transports and commercial cargo aircraft which will possess low-speed, high-lift capability by virtue of leading edge vortex generation and control without recourse to heavy and expensive leading edge high-lift devices and compound airfoils. Attention is given to interactive graphics simulation devices recently developed.
    Keywords: AERODYNAMICS
    Type: Astronautics and Aeronautics; 19; May 1981
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