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961.
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
962.
V.C. Liu 《Progress in Aerospace Sciences》1975,16(3):273-297
This paper presents theoretical methods to determine the gas dynamic and the electrostatic effects due to the interaction caused by a rapidly moving body in the ionosphere. The principles of the methods are derived from the kinetic theory of collision-free plasma. It is shown that the collective behavior of the collision-free plasma makes it possible to use the fluid approach to treat the problems of ionospheric aerodynamics. Various solutions to the system of fluid and field equations that have direct bearing on the ionospheric aerodynamics are presented and discussed. Physical significances of the mathematical results are stressed. Some outstanding unsolved problems in ionospheric aerodynamics are elaborated and discussed. 相似文献
963.
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
964.
The authors provide an overview of expert systems and how they may effect the development of future defense applications. Military uses of computers are outlined, and expert-systems fundamentals are described. Artificial research and development efforts by the military are examined, and potential military applications are discussed. Expert systems efforts at NASA, by the US Air Force, and for the Strategic Defence Initiative are considered 相似文献
965.
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
966.
Gordon D. Holman 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(11):181-183
Theoretical work on the interpretation of high brightness temperature microwave spike emission is reviewed, with emphasis upon recent contributions from the University of Maryland. Recent work on the interpretation of the spike emission as gyrosynchrotron masering is reviewed. Two alternative radiation mechanisms, stimulated plasma emission from the coherent intraction of electrostatic upper hybrid waves and from the interaction of electron plasma waves, are also discussed. 相似文献
967.
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
968.
969.
D. Wonnacott 《Space Science Reviews》1989,49(3-4):375
Simulations of the Algol-like binary CX Draconis, combined with IUE observations of the stream of material escaping the system can place limits on the inclination of the system and give estimates, via line profile synthesis, of the mass-loss rate at the L1 point. 相似文献
970.
We discuss evolutionary processes in binaries where the primary becomes a red giant with a deep convective envelope before it fills its Roche lobe. Such binaries (late Case B or late Case C, if they evolve conservatively) ought to suffer drastic mass transfer, on a hydrodynamic timescale. In some circumstances this may lead to a common envelope, spiral-in, and finally either a very short-period binary or coalescence. But there appear to be other circumstances in which the outcome is an ordinary Algol, or a wide binary with a white dwarf companion as in Barium stars and some symbiotics. We try to demonstrate that stellar-wind mass loss, enhanced one or two orders of magnitude by tidal interaction with a companion, can vitally affect the approach to RLOF, and indeed may prevent RLOF in binaries with periods over 1000 d. Such mass loss is probably accompanied by angular momentum loss, by magnetic braking combined with tidal friction. The result is that it will not be easy to predict definitively the outcome of evolution in a given zero-age binary. 相似文献