29,528 research outputs found
Microwave Power Transmission Workshop summary
The assumptions, methodologies, and conclusions of the NASA SPS studies were assessed and criticized to identify critical issues and to make recommendations for follow-on works. An assessment of the following items was made: beam forming and control, microwave amplifiers, radiating elements, and the rectenna. It was concluded that top priority should be given to determining an upper limit for permissible microwave power density which can be sent through the ionosphere
Offshore rectenna feasbility
A preliminary study of the feasibility and cost of an offshore rectenna to serve the upper metropolitan east coast was performed. A candidate site at which to build a 5 GW rectenna was selected on the basis of proximity to load centers, avoidance of shipping lanes, sea floor terrain, and relocated conditions. Several types of support structures were selected for study based initially on the reference system rectenna concept of a wire mesh ground screen and dipoles each with its own rectifier and filter circuits. Possible secondary uses of an offshore rectenna were examined and are evaluated
A computer model of solar panel-plasma interactions
High power solar arrays for satellite power systems are presently being planned with dimensions of kilometers, and with tens of kilovolts distributed over their surface. Such systems face many plasma interaction problems, such as power leakage to the plasma, particle focusing, and anomalous arcing. These effects cannot be adequately modeled without detailed knowledge of the plasma sheath structure and space charge effects. Laboratory studies of 1 by 10 meter solar array in a simulated low Earth orbit plasma are discussed. The plasma screening process is discussed, program theory is outlined, and a series of calibration models is presented. These models are designed to demonstrate that PANEL is capable of accurate self consistant space charge calculations. Such models include PANEL predictions for the Child-Langmuir diode problem
The mechanical properties of inconel 718 sheet alloy at 800 deg, 1000 deg, and 1200 deg f
Mechanical properties of Inconel sheet superalloy at very high temperatures for supersonic transpor
Lunar interactions: Abstracts of papers presented at the Conference on Interactions of the Interplanetary Plasma with the Modern and Ancient Moon
Reviewed are the active mechanisms relating the moon to its environment and the linkage between these mechanisms and their records in the lunar sample and geophysical data. Topics: (1) large scale plasma interactions with the moon and non-magnetic planets; (2) ancient and present day lunar surface magnetic and electric fields; (3) dynamics and evolution of the lunar atmosphere; (4) evolution of the solar plasma; (5) lunar record of solar radiations; (6) non-meteoritic and meteoritic disturbance and transport of lunar surface materials; and (7) future lunar exploration
Applications Technology Satellite /ATS-1/ Suprathermal Ion Detector experiment /SID/ data reduction and analysis Final report, 6 Dec. 1966 - 30 Mar. 1970
Data analysis on ATS-1 Suprathermal Ion Detector /SID/ measurements of low energy plasma flow in magnetopause boundar
Power law burst and inter-burst interval distributions in the solar wind: turbulence or dissipative SOC ?
We calculate for the first time the probability density functions (PDFs) P of
burst energy e, duration T and inter-burst interval tau for a known turbulent
system in nature. Bursts in the earth-sun component of the Poynting flux at 1
AU in the solar wind were measured using the MFI and SWE experiments on the
NASA WIND spacecraft. We find P(e) and P(T) to be power laws, consistent with
self-organised criticality (SOC). We find also a power law form for P(tau) that
distinguishes this turbulent cascade from the exponential P(tau) of ideal SOC,
but not from some other SOC-like sandpile models. We discuss the implications
for the relation between SOC and turbulence.Comment: 3 pages, 1 figure. Submitted to PRL on 25th February 2000. Revised
version re-submitted on 9th May 2000. Second revised version submitted Phys.
Rev. E on 26th June, 200
Investigation of the relation between solar variations and weather on earth as shown by study of simultaneous data from the sun, Mariner II, near-earth satellites and the atmosphere below the mesosphere
Relation of solar variations and wind to weather on earth shown by data from sun, Mariner II, ATMOSPHERE, and near-earth satellite
Sensitivity of the creep-rupture properties of nickel-base superalloy sheet to sharp edge-notches in the temperature range of 1000 deg F - 1400 deg F
Edge notch sensitivity in thin sheet nickel alloys under stress at high temperature
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