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Ruyten, Wilhelmus M.; Keefer, Denni
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We report the results of spectroscopic measurements on the exhaust plume from a 1 kW NASA Lewis arcjet, operated on simulated ammonia. The strongest emission features consist of the Balmer lines of atomic hydrogen and a number of vibration-rotation bands of the NH radical. From the spectral data, we calculate a heavy particle temperature of about 3000 K at the exit plane, and an electron temperature of 0.30 eV. Measurements of the spatial distribution of these emission features are presented...
Topics: MEASURING INSTRUMENTS, SPACE SHUTTLES, WIND EFFECTS, WIND MEASUREMENT, WIND VELOCITY, MECHANICAL...
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Blanchard, R. C.; Ozoroski, Thomas A.; Nicholson, John Y
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Calibrated pressure measurements for species with mass-to-charge ratios up to 50 amu/e(-) were obtained trom the shuttle upper atmosphere mass spectrometer experiment during re-entry on the STS-35 mission. The principal experimental objective is to obtain measurements of freestream density in the hypersonic rarefied flow flight regime. Data were collected from 180 to about 87 km. However, data above 115 km were contaminated from a source of gas emanating from pressure transdueers connected in...
Topics: ERROR ANALYSIS, WIND MEASUREMENT, VORTICITY, TEMPERATURE GRADIENTS, HORIZONTAL ORIENTATION,...
The dynamics are investigated of the lower thermosphere through comparison of optical observations of motions of ejected vapor trails with radar observations of motions of ionized meteor trails. In particular, the winds obtained from a series of vapor trail observations which occurred at Wallops Island, Virginia during the night of 14-15 December 1970 are to be compared with wind data deduced from radar observations of meteor trails during the same period. The comparison of these data is...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CIRCULATION, CONTRAILS, METEOR TRAILS, VISUAL...
Computer program was developed as prelaunch wind monitoring tool for Saturn 5 vehicle. Program accounts for characteristic wind changes including turbulence power spectral density, wind shear, peak wind velocity, altitude, and wind direction using stored variational statistics.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC TURBULENCE, COMPUTER PROGRAMS, POWER SPECTRA,...
An apparatus is described for sensing the temperature, velocity, and direction of the wind, including four temperature-dependent crystal oscillators spaced about an axis, a heater centered on the axis, and a screen through which the wind blows to pass over the crystals. In one method of operation, the frequency of the oscillators is taken when the heater is not energized, to obtain the temperature of the wind, and the frequencies of the oscillators are taken after the heater is energized to...
Topics: NASA Technical Reports Server (NTRS), REMOTE SENSORS, TEMPERATURE MEASUREMENT, WIND MEASUREMENT,...
Wind turbine generator research programs administered by the Energy Research and Development Administration are examined. The design and operation of turbine demonstration models are described. Wind assessments were made to determine the feasibility of using wind generated power for various parts of the country.
Topics: NASA Technical Reports Server (NTRS), WINDMILLS (WINDPOWERED MACHINES), WINDPOWER UTILIZATION,...
Tropospheric flow and lower stratospheric flow as measured by 94 sequences of high-resolution Jimsphere balloon data are presented and discussed. The 70 and 24 sequential series are presented for the Kennedy Space Center, Florida, and Point Mugu, California, areas, respectively. Supplemental data, consisting of the associative temperature profiles and surface and 200 mb synoptic maps, are also presented. The measurements are discussed relative to both the engineering and disciplinary areas. An...
Topics: NASA Technical Reports Server (NTRS), HIGH RESOLUTION, SEQUENTIAL ANALYSIS, WIND MEASUREMENT, WIND...
NASA Langley Research Center has been developing 2-micron lidar technologies over a decade for wind measurements, utilizing coherent Doppler wind lidar technique and carbon dioxide measurements, utilizing Differential Absorption Lidar (DIAL) technique. Significant advancements have been made towards developing state-of-the-art technologies towards laser transmitters, detectors, and receiver systems. These efforts have led to the development of solid-state lasers with high pulse energy,...
Topics: NASA Technical Reports Server (NTRS), DIFFERENTIAL ABSORPTION LIDAR, LASER APPLICATIONS, OPTICAL...
Even though solar wind, as a collisionless plasma, is properly described by the kineticMaxwell-Vlasov description, it can be argued that much of our understanding of solar wind observational data comes from an interpretation and numerical modeling which is based on a fluid description of magnetohydrodynamics. In recent years, there has been a significant interest in better understanding the importance of kinetic effects, i.e. the differences between the kinetic and usual fluid descriptions....
Topics: NASA Technical Reports Server (NTRS), SOLAR WIND, MAGNETOHYDRODYNAMICS, KINETIC THEORY, LANDAU...
Atmospheric wind data are required by space launch vehicles in order to assess flight vehicle loads and performance on day-of-launch. Space launch ranges at NASA's Kennedy Space Center co-located with the United States Air Force's (USAF) Eastern Range (ER) at Cape Canaveral Air Force Station and USAF's Western Range (WR) at Vandenberg Air Force Base have extensive networks of in-situ and remote sensing instrumentation to measure atmospheric winds. Each instrument's technique to measure winds...
Topics: NASA Technical Reports Server (NTRS), WIND PROFILES, LAUNCH VEHICLES, ASCENT TRAJECTORIES,...
Since many of the larger launch vehicles are operated near their design limits during the ascent phase of flight to optimize payload to orbit, it often becomes necessary to verify that the vehicle will remain within certification limits during the ascent phase as part of the go/no-go review made prior to launch. This paper describes the approach used to predict Ares I-X launch vehicle structural air loads and controllability prior to launch which represents a distinct departure from the...
Topics: NASA Technical Reports Server (NTRS), LAUNCHING, WIND MEASUREMENT, AERODYNAMIC LOADS, ARES 1 LAUNCH...
This Quarter's Highlights incllude: completion of the second phase of verifying the performance of the MesoNAM weather model at Kennedy Space Center (KSC) and Cape Canaveral Air Force Station (CCAFS). (1) The data was delivered to the 45th Weather Squadron (45 WS) and the final report was distributed (2) Staff completed modifying and updating lightning c1imatologies for KSC/CCAFS and other airfields around central Florida. We delivered the tool to the National Weather Service in Melbourne and...
Topics: NASA Technical Reports Server (NTRS), METEOROLOGY, WIND (METEOROLOGY), WIND MEASUREMENT, FLIGHT...
Sounding data which were derived from VAS radiance measurements and anticipated increased time and space resolution of the mesoscale environment are outlined. The new data presents problems which are not encounted when using conventional measurements because of the irregular spacing of the data, biases in the data, and errors due to cloud contaminated measurements. These problems are addressed and an analysis technique which utilizes LFM guess fields to produce a consistent four dimensional...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC SOUNDING, RADIANCE, VISIBLE INFRARED SPIN SCAN...
Several recent observations of thermospheric dynamics, made in the polar regions during extremely disturbed geomagnetic periods are reviewed. In general, the magnitude and the variability of winds in the thermospheric polar regions increases with magnetic activity, as measured by any of the conventional indices. However, none of the conventional indices is a particularly good aid to predicting wind magnitudes. In very general terms, two major factors may be considered in describing the wind...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CIRCULATION, MAGNETIC STORMS, THERMOSPHERE, TIME...
The goal of the research is a variational data assimilation method that incorporates as dynamical constraints, the primitive equations for a moist, convectively unstable atmosphere and the radiative transfer equation. Variables to be adjusted include the three-dimensional vector wind, height, temperature, and moisture from rawinsonde data, and cloud-wind vectors, moisture, and radiance from satellite data. In order to facilitate thorough analysis of each of the model components, four...
Topics: NASA Technical Reports Server (NTRS), COMPUTER PROGRAMMING, DATA PROCESSING, MATHEMATICAL MODELS,...
A service called the Optimum Path Aircraft Routing System (OPARS) supplies products based on output data from the Naval Oceanographic Global Atmospheric Prediction System (NOGAPS), a model run on a Cyber-205 computer. Temperatures and winds are extracted from the surface to 100 mb, approximately 55,000 ft. Forecast winds are available in six-hour time steps.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MODELS, AVIATION METEOROLOGY, NUMERICAL WEATHER...
Wind sensing using a Doppler lidar is achieved by sensing the Doppler content of narrow frequency laser light backscattered by the ambient atmospheric aerosols. The derived radial wind components along several directions are used to generate wind vectors, typically using the Velocity Azimuth Display (VAD) method described below. Range resolved information is obtained by range gating the continuous scattered return. For a CO2 laser (10.6 mu) the Doppler velocity scaling factor is 188 kHz/ms(exp...
Topics: NASA Technical Reports Server (NTRS), CARBON DIOXIDE LASERS, DOPPLER RADAR, METEOROLOGICAL RADAR,...
The development of eye-safe, solid-state Lidar systems is discussed, with an emphasis on Coherent Doppler Lidar for Atmospheric Wind Measurements. The following subject areas are covered: tunable Ho DIAL (Differential Absorption Lidar)/lidar atmospheric measurements; atmospheric turbulence measurements and detector arrays; diurnal measurements of C(sub n)(sup 2) for KSC lidar measurements; and development of single-frequency Ho laser/lidar.
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC TURBULENCE, BACKSCATTERING, CARBON DIOXIDE...
Flight test operations concerning the Joint NASA/FAA Airborne Wind Shear Detection and Avoidance Program 1991 Flight Experiments are presented in viewgraph form and include the following: research aircraft sensor installations; wind shear reactive sensor operation; wind shear IR sensor operation; wind shear radar sensor operation; wind shear lidar sensor operation; and 1991 flight test summary.
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT INSTRUMENTS, FLIGHT TESTS, INFRARED DETECTORS,...
Twice-daily values of the atmosphere's angular momentum about the polar axis during the five years from 1976 through 1980 are presented in graphs and a table. The compilation is based on a global data set, incorporating 90 percent of the mass of the atmosphere. The relationship between changes in the angular momentum of the atmosphere and changes in the length of day is described, as are the main sources of error in the data. The variability in angular momentum is revealed in a preliminary...
Topics: NASA Technical Reports Server (NTRS), ANGULAR MOMENTUM, ATMOSPHERIC CIRCULATION, DIURNAL...
Synoptic weather conditions existing over the western United States for the time of Shuttle descent are presented. The techniques and methods used to furnish synoptic atmospheric data at the surface and aloft for flight verification of the STS 3 orbiter during its descent are specified. Examples of the upper level data set are given.
Topics: NASA Technical Reports Server (NTRS), SPACE SHUTTLE ORBITERS, SPACE TRANSPORTATION SYSTEM 3 FLIGHT,...
Analysis of data obtained from the Joint Airport Weather Studies Flights 6 and 7 is underway. Data from Flight 7 indicate that the B-57B encountered the upper portion of an outflow feature (microburst) at an altitude of 400 meters above ground level. Horizontal wind vector plots along the flight path have provided clues concerning the meteorological setting of the flights. In addition to suspected outflow features, wavelike variations of the horizontal wind vectors were observed. Statistical...
Topics: NASA Technical Reports Server (NTRS), AIRPORTS, B-57 AIRCRAFT, GUST LOADS, METEOROLOGICAL FLIGHT,...
Analysis of data collected during the participation of the MSFC 10.6 micron pulsed Doppler lidar system (DLS) in the Joint Airport Weather Studies (JAWS) experiment is concluded. Observations from more than one Doppler lidar are combined to derive the three-dimensional Cartesian wind field. A comparison of radial velocity estimates at low elevations made by the MSFC lidar and the NCAR 5.5 cm Doppler radar revealed a substantial r.m.s. difference of 3 mls, and a mean difference of lmls. Detailed...
Topics: NASA Technical Reports Server (NTRS), DOPPLER RADAR, GUSTS, METEOROLOGICAL INSTRUMENTS, OPTICAL...
New analysis methods were developed and refined for the synthesis of wind fields from multiple Doppler radar data. Considerable software was written and debugged for wind field synthesis. The analysis methods were applied to radar data collected during the CCOPE experiment in which lidar wind measurements were also made. The analysis method differs from existing methods in that interpolation (using filters with assigned weights) and advection of data, to account for time differential between...
Topics: NASA Technical Reports Server (NTRS), DATA PROCESSING, DOPPLER RADAR, OPTICAL RADAR, SOFTWARE...
A pilot data center to compute ocean atmosphere heat exchange over the tropical ocean is prposed at the Jet Propulsion Laboratory (JPL) in response to the scientific needs of the Tropical Ocean and Global Atmosphere (TOGA) Program. Optimal methods will be used to estimate sea surface temperature (SET), surface wind speed, and humidity from spaceborne observations. A monthly summary of these parameters will be used to compute ocean atmosphere latent heat exchanges. Monthly fields of surface heat...
Topics: NASA Technical Reports Server (NTRS), AIR WATER INTERACTIONS, DATA ACQUISITION, HEAT BUDGET,...
A new thermospheric wind measurement technique is reported which is based on a Satellite Electrostatic Triaxial Accelerometer (SETA) system capable of accurately measuring accelerations in the satellite's in-track, cross-track and radial directions. Data obtained during two time periods are presented. The first data set describes cross-track winds measured between 170 and 210 km during a 5-day period (25 to 29 March 1979) of mostly high geomagnetic activity. In the second data set, cross-track...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CIRCULATION, GAS DENSITY, MAGNETIC STORMS,...
The steps and engineering trades and analyses used in establishing the initial requirements and in developing a concept and configuration for the laser atmospheric wind sounder (LAWS) instrument. A summary of the performance anticipated from the baseline configuration, and a bibliography are presented. LAWS, which is a facility instrument of the Earth observing system (EOS), is the culmination of over 20 years of effort in the field of laser Doppler wind sensing and will be the first instrument...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC SOUNDING, CARBON DIOXIDE LASERS, DOPPLER RADAR,...
The merits of using lidar systems for remote measurements of various atmospheric processes such as wind, turbulence, moisture, and aerosol concentration are widely recognized. Although the lidar technology has progressed considerably over the past two decades, significant research particularly in the area of solid state lidars remains to be conducted in order to fully exploit this technology. The work performed by the UAH (University of Alabama in Huntsville) personnel under this Delivery Order...
Topics: NASA Technical Reports Server (NTRS), DATA BASES, LASER APPLICATIONS, OPTICAL MEASUREMENT, OPTICAL...
The Laser Atmospheric Wind Sounder (LAWS) has recently been deselected from the Earth Observing System (EOS). A broad range of orbital altitudes and laser power are being considered for future wind lidar missions. As a result, as was anticipated in the proposed work, it may be impossible to meaningfully study tropical cyclones with lidar wind data because data coverage (i.e., swath width) is insufficient. Research on this grant has focused on how to maximize the benefits of a wind lidar...
Topics: NASA Technical Reports Server (NTRS), CYCLOGENESIS, DOPPLER RADAR, EARTH OBSERVING SYSTEM (EOS),...
For over 20 years researchers have been investigating the feasibility of profiling tropospheric vector wind velocity from space with a pulsed Doppler lidar. Efforts have included theoretical development, system and mission studies, technology development, and ground-based and airborne measurements. Now NASA plans to take the next logical step towards enabling operational global tropospheric wind profiles by demonstrating horizontal wind measurements from the Space Shuttle in early 2001 using a...
Topics: NASA Technical Reports Server (NTRS), METEOROLOGICAL PARAMETERS, WIND MEASUREMENT, NUMERICAL...
The development of a ground based direct detection Doppler lidar based on the recently described aerosol double edge technique is reported. A pulsed, injection seeded Nd:YAG laser operating at 1064 nm is used to make range resolved measurements of atmospheric winds in the free troposphere. The wind measurements are determined by measuring the Doppler shift of the laser signal backscattered from atmospheric aerosols. The lidar instrument and double edge method are described and initial...
Topics: NASA Technical Reports Server (NTRS), GROUND BASED CONTROL, DOPPLER RADAR, OPTICAL RADAR, RADAR...
The design of an orbiting wind profiling lidar requires selection of dozens of lidar, measurement scenario, and mission geometry parameters; in addition to prediction of atmospheric parameters. Typical mission designs do not include a thorough trade optimization of all of these parameters. We report here the integration of a recently published parameterization of coherent lidar wind velocity measurement performance with an orbiting coherent wind lidar computer simulation; and the use of these...
Topics: NASA Technical Reports Server (NTRS), METEOROLOGICAL PARAMETERS, OPTICAL RADAR, RADAR MEASUREMENT,...
This document presents results of a field study of the effect of sensor spacing on the validity of wind measurements at the Space Shuttle landing Facility (SLF). Standard measurements are made at one second intervals from 30 foot (9.1m) towers located 500 feet (152m) from the SLF centerline. The centerline winds are not exactly the same as those measured by the towers. This study quantifies the differences as a function of statistics of the observed winds and distance between the measurements...
Topics: NASA Technical Reports Server (NTRS), DATA PROCESSING, LANDING SITES, WIND MEASUREMENT, WIND...
The first draft of a manuscript titled "Variable time delays in the propagation of the interplanetary magnetic field" has been completed, for submission to the Journal of Geophysical Research. In the preparation of this manuscript all data and analysis programs had been updated to the highest temporal resolution possible, at 16 seconds or better. The program which computes the "measured" IMF propagation time delays from these data has also undergone another improvement. In...
Topics: NASA Technical Reports Server (NTRS), SOLAR WIND, COUPLING, INTERPLANETARY MAGNETIC FIELDS, WIND...
This report describes results of the AMU's Instrumentation and Measurement task for evaluation of the Doppler miniSODAR(TradeMark) System (DmSS). The DmSS is an acoustic wind profiler providing high resolution data to a height of approx. 410 ft. The Boeing Company installed a DmSS near Space Launch Complex 37 in mid-2002 as a substitute for a tall wind tower and plans to use DmSS data for the analysis and forecasting of winds during ground and launch operations. Peak wind speed data are of...
Topics: NASA Technical Reports Server (NTRS), WIND MEASUREMENT, SPACECRAFT LAUNCHING, GROUND OPERATIONAL...
High-energy 2-microns lasers have been incorporated in a breadboard coherent Doppler lidar to test component technologies and explore applications for remote sensing of the atmosphere. Design of the lidar is presented including aspects in the laser transmitter, receiver, photodetector, and signal processing. Sample data is presented on wind profiling and CO2 concentration measurements.
Topics: NASA Technical Reports Server (NTRS), BREADBOARD MODELS, DOPPLER RADAR, LASERS, REMOTE SENSING,...
The purpose of this grant, 'Towards the Development of a Unified Distributed Data System for L1 Spacecraft', is to take the initial steps towards the development of a data distribution mechanism for making in-situ measurements more easily accessible to the scientific community. Our obligations as subcontractors to this grant are to add our Faraday Cup plasma data to this initial study and to contribute to the design of a general data distribution system. The year 1 objectives of the overall...
Topics: NASA Technical Reports Server (NTRS), IN SITU MEASUREMENT, DOCUMENT MARKUP LANGUAGES, DATA SYSTEMS,...
Given current resources and the technical challenges in developing a full coverage space-based Doppler lidar wind measuring system such as LAWS (Laser Atmospheric Wind Sounder), it is not likely that the science community will have data streams with which to work before the end of this decade. Currently, a 'fast track' demonstration mission is being seriously considered by several U.S. agencies. Such a mission would have as its primary objectives the demonstration of coherent Doppler lidar...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC SOUNDING, DOPPLER RADAR, LASER APPLICATIONS,...
The research objectives in this proposal were part of a continuing program at UW-CIMSS to develop and refine an automated geostationary satellite winds processing system which can be utilized in both research and operational environments. The majority of the originally proposed tasks were successfully accomplished, and in some cases the progress exceeded the original goals. Much of the research and development supported by this grant resulted in upgrades and modifications to the existing...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC MOISTURE, AUTOMATIC CONTROL, CLOUDS...
Over the past few years, considerable advances have been made in the areas of the diode-pumped, eye-safe, solid state lasers, wide bandwidth, semiconductor detectors operating in the near-infrared region. These advances have created new possibilities for the development of low-cost, reliable, and compact coherent lidar systems for measurements of atmospheric winds and aerosol backscattering from a space-based platform. The work performed by the UAH personnel concentrated on design and analyses...
Topics: NASA Technical Reports Server (NTRS), OPTICAL RADAR, SOLID STATE LASERS, DESIGN ANALYSIS, COHERENT...
In this paper, we present a description of the internal dynamics and boundary forcing characteristics of two major components of the Asian summer monsoon (ASM), i.e., the South Asian (SAM) and the Southeast-East Asian monsoon (SEAM). The description is based on a new monsoon-climate paradigm in which the variability of ASM is considered as the outcome of the interplay of a "fast" and an "intermediate" monsoon subsystem, under the influenced of the "slow" varying...
Topics: NASA Technical Reports Server (NTRS), MONSOONS, WIND MEASUREMENT, TEMPERATE REGIONS, SEA SURFACE...
Chemical data from flight 8 of NASA's Subsonic Assessment (SASS) Ozone and Nitrogen Oxide Experiment (SONEX) exhibited signatures consistent with aircraft emissions, stratospheric air, and surface-based pollution. These signatures are examined in detail, focussing on the broad aircraft emission signatures that are several hundred kilometers in length. A mesoscale meteorological model provides high resolution wind data that are used to calculate backward trajectories arriving at locations along...
Topics: NASA Technical Reports Server (NTRS), OZONE, TIME SERIES ANALYSIS, MESOMETEOROLOGY, MESOSCALE...
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Kestenboym, Kh. S., et al
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Strong point explosion in exponential atmosphere without consideration of real properties of air
Topics: CROSS CORRELATION, WIND MEASUREMENT, PHOTOMETERS, PROBABILITY DENSITY FUNCTIONS, TURBULENT FLOW,...
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Leonov, A. A.; Lebedev, V. I
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Psychological compatibility among crew members of an interplanetary ship is examined under the conditions of group isolation, the extended effect of weightlessness on human mental processes, the effect of sensory and information starvation on the appearance of unusual mental states, emotional stress, and the rhythm of working and rest.
Topics: CLEAR AIR TURBULENCE, METEOROLOGICAL PARAMETERS, SYNOPTIC METEOROLOGY, MOUNTAINS, RAWINSONDES,...
Experimental and theoretical studies were performed of atmospheric aerosol backscatter and atmospheric dynamics with Doppler lidar as a primary tool. Activities include field and laboratory measurement and analysis efforts. The primary focus of activities related to understanding aerosol backscatter is the GLObal Backscatter Experiment (GLOBE) program. GLOBE is a multi-element effort designed toward developing a global aerosol model to describe tropospheric clean background backscatter...
Topics: NASA Technical Reports Server (NTRS), AEROSOLS, AIRBORNE EQUIPMENT, ATMOSPHERIC SCATTERING,...
This publication contains extended abstracts of papers presented at the 16th International Laser Radar Conference. One-hundred ninety-five papers were presented in both oral and poster sessions. The topics of the conference sessions were: (1) Mt. Pinatubo Volcanic Dust Layer Observations; (2) Global Change/Ozone Measurements; (3) GLOBE/LAWS/LITE; (4) Mesospheric Measurements and Measurement Systems; (5) Middle Atmosphere; (6) Wind Measurements and Measurement Systems; (7) Imaging and Ranging;...
Topics: NASA Technical Reports Server (NTRS), ATMOSPHERIC CIRCULATION, ATMOSPHERIC EFFECTS, BACKSCATTERING,...
The wind power potential of Alaska is assessed in order to determine promising windpower sites for construction of wind machines and for shipment of wind derived energy. Analyses of near surface wind data from promising Aleutian sites accessible by ocean transport indicate probable velocity regimes and also present deficiencies in available data. It is shown that winds for some degree of power generation are available 77 percent of the time in the Aleutians with peak velocities depending on...
Topics: NASA Technical Reports Server (NTRS), ALASKA, ENERGY SOURCES, GROUND WIND, WINDPOWER UTILIZATION,...
The potential of very-long-baseline interferometry (VLBI) is examined for use in the determination of wind speeds in Venus' lower atmosphere via the differential tracking of entry probes. A simplified mathematical model is presented in detail. An incomplete error analysis based on this model permits an educated guess to be made: an uncertainty in wind speed determination of no more than about 100/t m/sec, where t l is the corresponding time resolution in seconds, is an achievable goal, without...
Topics: NASA Technical Reports Server (NTRS), INTERFEROMETRY, VENUS ATMOSPHERE, VENUS PROBES, WIND...
Preliminary observations at 13.9 GHz of the radar backscatter and microwave emission from the sea were analyzed using data obtained by the radiometer scatterometer on Skylab. Results indicate approximately a square-law relationship between differential scattering coefficient and windspeed at angles of 40 deg to 50 deg, after correction for directional effect, over a range from about 4 up to about 25 meters/sec. The brightness temperature response was also observed, and considerable success was...
Topics: NASA Technical Reports Server (NTRS), OCEAN CURRENTS, SKYLAB PROGRAM, BACKSCATTERING, MICROWAVES,...
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Araki, Noriyuki; Shinonaga, Hideyuki; Ito, Yasuhik
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Two networking issues of communications systems with medium earth orbit (MEO) satellites, namely network architectures and location determination and registration methods for hand-held terminals, are investigated in this paper. For network architecture, five candidate architectures are considered and evaluated in terms of signaling traffic. For location determination and registration, two methods are discussed and evaluated.
Topics: ATMOSPHERIC SOUNDING, CARBON DIOXIDE LASERS, CONTROL EQUIPMENT, DESIGN ANALYSIS, FAULT TOLERANCE,...
