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951.
G. Hasinger W. Pietsch C. Reppin J. Trümper W. Voges E. Kendziorra R. Staubert 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
The Crab was observed in a balloon flight from Palestine/Texas on 9/28/81 at hard X-ray energies (20–200 keV). The light curve is significantly sharper than reported previously for this energy range. The pulse-averaged as well as the interpulse spectra show breaks in our energy-range. The variation of spectral index across the pulse has an amplitude similar to that found at lower energies by OSO-8 and larger than reported by HEAO-1 A4 at hard X-rays. For a sharp emission line at 77 keV a 99% upper limit of 1.0*10−3 photons/ cm2 sec can be placed, a factor of 4 lower than line fluxes reported previously. Pulse-shape fits to the optical, X-ray, hard X-ray and gamma ray light-curves reveal a consistent picture of the origin of the interpulse and off-pulse emission, the breaks in the spectra and the variation of spectral index, providing arguments against a thermal component and also a polar cap emission model for NP0532. 相似文献
952.
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
953.
Marcos E. Machado Gustavo Lerner 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(7):239-241
We show that the observations of a limb flare, in which a hard X-ray (16–30 keV) source is seen at the boundary between two interacting magnetic structures, indicate the presence of hot (T ? 6 × 107 K) plasma within the region. Non thermal bremsstrahlung processes do not agree with these observations. We discuss the possible causes of the heating. 相似文献
954.
955.
L. Schaffer J.A. Burns 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(9):107-110
We outline an analytical method for studying the motion of charged dust particles that orbit an oblate planet having a tilted, offset, dipolar magnetic field. Our computed trajectories closely mimic previous numerical results; equilibrium dust potentials must be less then 10 volts or the Jovian ring would be thicker than observed. We identify several , where the periods of components of the Lorentz force, as seen by a reference particle moving in the equatorial plane, match the particle's orbital period; several seem to be near observed features of the Jovian ring system. 相似文献
956.
A. Berroir P. de Felice L. Pontier P. Sitbon 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(6):125-131
The principle of determination of wind fields by a tomographic method is described. The airborne stereoscopic radiometer JANUS has been built to assess the feasibility of such measurements. Results of preliminary flights over isolated cumulus compare favourably with direct measurements. New flights with improved auxiliary parameter determinations are ongoing. 相似文献
957.
S.S. Gaigerov M.Ya. Kalikhman V.V. Fedorov E.D. Zhorova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(1):29-32
Circulation and thermal structure for the 90–95 km region is described on the basis of the joint analysis of direct and indirect sounding data. Mean season charts of the 0.001 mb surface were compiled using data from meteor trials, ionospheric drifts, rocket launchings and data of the rotational temperature of hydroxyl emission. 相似文献
958.
Tomas E. Gergely 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(11):271-284
Using data available at the present time, a summary of the significant solar-terrestrial events of STIP Interval XII (April 10–July 1, 1981) has been prepared. The first half of the interval was extremely active, several of the largest X-ray flares, particle events, and shocks of the present solar cycle took place during April and the first half of May. The second half of the interval, on the other hand, was characterized by relatively quiet conditions. Several large events which occurred on 10, 24 and 27 April and on 8 and 16 May are discussed in some detail. It is suggested that one of the most interesting subjects of future study could be the comparison and statistical analysis of the numerous events for which excellent observations are available, e.g. on what causes a type II burst to propagate in the interplanetary medium. 相似文献
959.
R. E. Halpern 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1988,8(12):89-95
The United States has begun the development of an international Space Station complex in cooperation with Japan, Canada, and the European Space Agency. The planned uses of the facility encompass a broad spectrum of research disciplines including life sciences, material sciences, astrophysics, earth sciences and planetary sciences. Activity has already started on the preparation of scientific proposals, and in some cases on specific pieces of instrumentation, in many of these areas. Long-duration, continuous research in space in a manned facility presents situations, problems and opportunities which have never before needed to be addressed. This paper presents current thinking in the United States on several of these issues related specifically to the microgravity sciences and an initial paradigm for their solution. 相似文献
960.
Stark L. Tendick F. Kim W. Anderson R. Hisey M. Mills B. Matsunaga K. An Nguyen Ramos C. Tyler M. Zahalak G. Amick M. Baker B. Brown N. Brown T. Chang J. Jyh-Horng Chen Chik J. Cohen D. Cox D. Dubey J. Ellis K. Engdahl E. Frederickson C. Halamka J. Hauser R. Jacobs J. Lee C. Lee D. Liu A. Ninomiya R. Rudolph J. Schafer S. Schendel E. So G. Takeda M. Tam L. Thompson M. Wood E. Woodruff T. 《IEEE transactions on aerospace and electronic systems》1988,24(5):542-551
With major emphasis on simulation, a university laboratory telerobotics facility permits problems to be approached by groups of graduate students. Helmet-mounded displays provide realism; the slaving of the display to the human operator's viewpoint gives a sense of `telepresence' that may be useful for prolonged tasks. Using top-down 3-D model control of distant images allows distant images to be reduced to a few parameters to update the model used for display to the human operator in a preview model to circumvent, in part, the communication delay. Also, the model can be used as a format for supervisory control and permit short-term local autonomous operations. Image processing algorithms can be made simpler and faster without trying to construct sensible images from the bottom. Control studies of telerobots lead to preferential manual control modes and, in this university environment, to basic paradigms for human motion and thence, perhaps, to redesign of robotic control, trajectory path planning, and rehabilitation prosthetics. Speculation as to future industrial drives for this telerobotic field suggests efficient roles for government agencies such as NASA 相似文献