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121.
A human factors perspective for creating intelligent cockpits is described and explained. A conceptualized interface among the pilots, mental models, and human information technologies is proposed wherein knowledge concerning human cognition is meshed with the capabilities and limitations of artificial intelligence (AI). Necessarily, a different way of looking at the pilot's role in the intelligent cockpit is developed.  相似文献   
122.
During August 1981, a 50 MHz c.w. radar system was operated in central Canada to measure auroral scatter amplitudes and Doppler spectra from a scattering region centered near 66° magnetic invariant latitude (L ≈ 6.0). Narrow beams from 3 transmitters, differing in frequency by 1 KHz, were directed to cover a common volume of the ionosphere over a ground location at 56.3°N, 103.5°W. The scattered signals were received on narrow beam antennas at two receiving sites, and recorded in analog form on magnetic tape under the control of an AIM65 microcomputer. The analog tapes were digitized later and FFT-processed to obtain Doppler spectra and amplitudes.The 6 transmission paths were designed to provide several magnetic aspect angles varying by 1.5°-7° from perpendicularity with the earth's field B and two streaming aspect angles differing by ~38°. The objective was to employ controlled geometric factors to study the functional dependency of signal amplitudes and Doppler shifts on magnetic and streaming aspect angles. Several hundred hours of excellent data were obtained in continuous operation during the month of August 1981. Preliminary results will be reported.  相似文献   
123.
The effects of gravity waves on OH and 5577 0I emissions have been used to investigate (1) the possible production of “secondary” waves or “ripples” by a “primary” wave; (2) the possible application of such observed optical emissions for computing atmospheric parameters such as turbulence viscosity in the mesospheric regions.  相似文献   
124.
Observations of solar cosmic ray events far from the sun (?1 AU) became possible after the launch of Pioneer 10 in 1972. Four spacecraft have now travelled beyond the orbit of Jupiter - Pioneer 10/11 and Voyager 1/2 — and are producing a growing body of distant observations of solar cosmic ray events. Initial studies using Pioneer 10/11 data out to ~6 AU interpreted flare particle observations in terms of a diffusion model, including the effects of convection and adiabatic energy loss. This model enjoyed general success in explaining the time-intensity profiles in cases where the spacecraft connection longitude at the sun did not change significantly with time. The results implied that the radial diffusion coefficient (Kr) increased slowly with distance over that radial range. More recent results at larger distances imply that Kr may begin to decrease beyond ~5 AU. It is not yet clear whether the standard diffusion model will be adequate to explain solar events well beyond 5 AU. The fact that large events at very large distances can last up to two solar rotations implies that solar wind stream structure will also play a role in the event dynamics. In general, however, observations at large distances offer perhaps the best hope of separating interplanetary propagation effects from coronal storage and propagation effects which frequently dominate observed event profiles at 1 AU.  相似文献   
125.
Recent studies of the lunar ejecta from lunar impacts of interplanetary dust particles indicate that during favorable lunar phases, over 80% of the submicron ejecta enters the earth's magnetosphere. This “pulse” of lunar ejecta produced by the sporadic meteor background will follow the random variations of the sporadic flux. An additional enhancement of this flux can be related to major meteor showers. Since the annual periods of these showers occur during varying lunar phase angles, magnetosphere ejecta flux associated with major showers will vary depending on the coincidence of shower periods and favorable lunar phase angles. The results of an analysis of the “pulse” of ejecta flux in the magnetosphere during the Quadrantids, Geminids, Leonids, and Perseids meteor showers are presented. These results are compared to the satellite measurements of 1959 Eta and HEOS II.  相似文献   
126.
One instrument of the Canadian Auroral Network for the Open Program Unified Study (CANOPUS) is a pulsed dual bistatic auroral radar system (BARS) for the mapping of ionospheric electric fields, using the STARE technique originated by R.A. Greenwald [14]. The Canadian system is presently in the specification and design phases, with the objective of being operational by mid-1984. This paper describes the geometry of the BARS system, the design considerations, and the planned data and control network.  相似文献   
127.
128.
The STructure and Atmospheric Turbulence Environment (STATE) experiment was conducted during the second week of June 1983 at Poker Flat Research Range, Alaska. The measurements focus on a study of the middle atmosphere dynamics by comparison between in-situ probe measurements and MST radar measurements. Rocket launchings were conducted at three periods which were selected by monitoring the doppler velocity spectra of the MST radar.The STATE program has included the efforts of several scientists in planning and carrying out the ground-based and rocket measurements. An overview of the program is given together with some preliminary results. The regions in intense backscatter signals detected by the MST radar are shown to correlate with large irregularities in the electron profiles measured.  相似文献   
129.
The Shuttle Activation Monitor (SAM) experiment was flown on the Space Shuttle Columbia (STS-28) from 8-13 August, 1989 in a 57 degrees, 300 km orbit. One objective of the SAM experiment was to determine the relative effect of different amounts of shielding on the gamma-ray backgrounds measured with similarly configured sodium iodide (NaI) and bismuth germante (BGO) detectors. To achieve this objective twenty-four hours of data were taken with each detector in the middeck of the Shuttle on the ceiling of the airlock (a high-shielding location) as well as on the sleep station wall (a low-shielding location). For the cosmic-ray induced background the results indicate an increased overall count rate in the 0.2 to 10 MeV energy range at the more highly shielded location, while in regions of trapped radiation the low shielding configuration gives higher rates at the low energy end of the spectrum.  相似文献   
130.
Loran-C and GPS were assessed for vehicular navigation along selected roads of British Columbia during the winter of 1991. The general topography of this mountainous area is described, together with the specific topographic features and tree coverage characteristics of the 2000 km of roads tested on the mainland and on Vancouver Island. The configuration and characteristics of the Loran C Canadian West Coast chain along the roads used are described. The portable vehicle-mounted system used to collect and analyze the Loran-C and GPS signals along road profiles is described. The performance of Loran-C is analyzed in terms of signal to noise ratios (SNR), field strength, and time-difference distortions, as measured by differential GPS. These distortions, which can reach several hundred meters over distances of less than 20 km, are analyzed in terms of topographic features. The possibility of using these time-independent distortions to calibrate Loran-C for use along the above roads is discussed. Masking of GPS signals due to topographic features and tree coverage along the roads is analyzed. A comparative analysis of both Loran-C and GPS is presented in terms of signal availability and accuracy  相似文献   
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