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441.
A hierarchical control architecture for telerobotic vehicles intended to yield a modular, flexible, and easily expanded control system is presented. This architecture is proposed for applications where simple teleoperation is required, but where additional capabilities might be quickly added without major changes to the control system. Similarities to the NASREM architecture are noted. Results for the hardware implementation of the control system on a telerobotic vehicle, RAYBOT, are given 相似文献
442.
S. I. Avdyushin M. B. Belotserkovsky V. Kim A. S. Koroteev A. M. Kulikov A. I. Livshits Yu. K. Melnikov R. I. Moisya N. N. Petrov H. A. Popov Yu. A. Romanovsky Yu. A. Utkin V. V. Chilap 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(12):163-167
Results of rocket experiments on study of plasma flows (PF) artificially injected by sources separated from vehicles and their effect on medium parameters in ionosphere at altitudes 160:230 km are presented.PF were injected comprising lithium ions with velocities 1,2 x 104 m/sec. and cesium-potassium ions with velocities (1,4–1,5)x103 m/sec. Mass flow rate in case of lithium PS is 2 mg/sec, and in case of cesium-potassium PS is 0,2 g/sec. During experiments mass-spectrometer measurements of ion medium content in ranges of different ion masses were held, disturbancies of electric fields with frequencies up to 20 kHz and electron flows with energies 0,7keV, 4,6keV and over 40 keV were controlled at distancies from 150m to (500–600)m between plasma source and scientific equipment. 相似文献
443.
444.
A.H. Manson C.E. Meek K. Labitzke 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(4):51-55
The global developments of the stratospheric events (~20–50 km) are briefly described using balloon and satellite data. Winds data from L.F. drift (52°N, 15°E, Europe) for heights of 90–100 km, and from M.F. radar (52°N, 107°W, Canada) for heights of 60–110 km are then compared with the stratospheric morphology.Data for 1982/3 and 1983/4 show that the planetary wave activity and warmings produced strong westward and southward perturbations in the radar winds. Satellite data from 0.1, 0.01 hPa are consistent with these winds; and also show smaller scale structures in the mesosphere than the stratosphere. The semi-diurnal tide responded strongly to the atmospheric disturbances in Europe and Canada: for the latter vertical wavelength changes occurred for heights of 70–100 km. However the correlation between these tidal fluctuations was not high indicating that the tidal adjustments were continental rather than hemispheric. 相似文献
445.
D.J. Michels N.R. Sheeley R.A. Howard M.J. Koomen R. Schwenn K.H. Mulhauser H. Rosenbauer 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(7):311-321
A small coronagraph has been placed in orbit to monitor the sun's outer corona from 2.5 to 10.0 solar radii, and five years of nearly continuous synoptic observations have now been completed. Rapid and sensitive image processing techniques have been developed to screen the data for transient phenomena, particularly coronal mass ejections (CMEs). About 50,000 coronal images have been examined, out of a five-year total of 68,000, and a standardized listing of more than 1,200 coronal transients for the period 1979–1982 has been prepared. These data have been analysed in the light of other available information, particularly on conditions in the interplanetary plasma. The dynamical characteristics of the active corona, as they are beginning to emerge from the data, are presented. We find that coronal mass ejections exercise significant influence on the interplanetary solar wind. They are the source of disturbances that are frequent and energetic, that tend to be somewhat focussed, that often reach shock intensity, and that propagate to large heliocentric distances, sometimes causing major geomagnetic storms. 相似文献
446.
The Earth's rotation is decelerating at a rate of 8.8×10 exp-20 rad/s. Thus, a leap second is added to the year every two to four years. This deceleration is small, but the Earth weighs 6×10 exp 24 kg. A prony brake that achieves this deceleration would release 5.14×10 exp 11 kW, the equivalent of 514,000 1-GW nuclear power plants. Tides, volcanos, Coriolis-generated ocean currents and winds cannot absorb this much power. This leaves the induction generation which produces the Earth's magnetic field as the most likely absorber of the deceleration power. The efficiency of this inaccessible induction generator cannot be calculated. However, it is thought that correlation of the Earth's deceleration with its 0.09% weakening magnetic field could provide insight into the power generation process 相似文献
447.
G Horneck H Bucker K Dose K D Martens A Bieger H D Mennigmann G Reitz H Requardt P Weber 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(10):19-27
Bacterial spores are proper test organisms for studying problems of space biology and exobiology. During the Spacelab 1 mission, studies on the limiting factors for survival of Bacillus subtilis spores in free space have been performed. An exposure tray on the pallet of Spacelab 1 accomodated 316 samples of dry spores for treatment with space vacuum and/or the following selected wavelengths of solar UV: > 170 nm, 220 nm, 240nm, 260nm and 280 nm. After recovery, inactivation, mutation induction, reparability, and photochemical damages in DNA and protein have been studied. The results contribute to the understanding of the mechanisms of increased UV sensitivity of bacterial spores in vacuo and to a better assessment of the chance of survival of resistant forms in space and of interplanetary transfer of life. 相似文献
448.
449.
H. Oya T. Ono 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):217-220
The stimulated plasma wave experiment (SPW) has been successfully carried out in the plasmasphere and the magnetosphere along the JIKIKEN (EXOS-B) satellite orbit where the plasma parameters indicate wide variety of the combination of the electron number density, ranging from 1/cc to 104/cc, and the electron cyclotron frequency, ranging from 6 kHz to 200 kHz.The upper hybrid resonances FUHR usually persists for long periods up to 125 msec and the electron cyclotron resonances nFH are stimulated at frequencies with the very high harmonic number n; sometimes, the nFH resonance takes place for n=47.All the features of the resonances including FOn reflect the characteristics of the magnetospheric plasma that contains the energetic and non-Maxwellian components of the particles. The measurement of the plasma resonance contributes to the detection of the local electron density and the magnetic field intensity. The mode of the propagating radio waves is also determined being compared with the observed local plasma resonance frequency Fp. 相似文献
450.
H.B. Niemann W.T. Kasprzak 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(10):261-270
Composition and gas density measurement at all altitudes in the atmospheres of earth and other planets are made by mass spectrometers. Because of the impartiality and large dynamic range they are particularly favored for exploratory missions. Measurements of trace constituents, inert gases and height profiles, especially below clouds, are objectives where mass spectrometry is most useful. Significant advances have been made in recent years in development of light weight automated instruments. Experiments conducted in rarified atmospheres have been more successful or results were less controversial than in attempts to analyze high pressure atmospheres. Gas sampling and conditioning techniques are highly specific because of measurement environments and engineering constraints on the mission, and are usually the most critical elements in the experiment. Chemical sample enrichment and scrubbing for noble gas enhancement are additional sample conditioning techniques now employed. Dynamic range of more than 108 is achievable. Reliable measurements of complex organic or chemically active trace constituents with mixing ratios of less than 10?9 still require significant instrument development particularly where weight, power and sampling time are severely restricted. Adaptation of familiar and proven laboratory techniques for flight instruments is usually not straightforward and practical. 相似文献