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441.
442.
G. Stanev M. Petrunova D. Teodosiev I. Kutiev K. Serafimov S. Chapkunov V. Chmyrev N. Isaev P. Puschaev I. Pimenov S. Bilichanko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(7):43-47
The instrument IESP-IPMP represents the complex unit measuring the vector of the DC electric field, the vectors of the electric and magnetic field in the frequency range of 0.2 – 6.5 Hz (wave form), autocorrelation functions of waves with frequencies of 0.1 – 5 kHz, and wave amplitudes in 8 bandpass channels. Some results are shown and compared in the various frequency ranges. 相似文献
443.
K. Frieler N. Phlippovich R. Stickler W. Bathke 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(5):117-120
Experiments of vacuum brazing under both microgravity and 1-g conditions show the effect of hydrostatic pressure on ga-filling. The absence of buoyancy forces under microgravity affects the microstructure of the solidified braze in the joint. 相似文献
444.
N.A. Savich 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(9):17-25
A comparison of the Venusian ionosphere electron density profiles obtained by the dual-frequency radio occultation method for the satellites Venera-9,10 (1975) and the Pioneer-Venus orbiter (1978–1979) has been carried out. It is shown that the general nature of the profiles, the main maximum heights and electron densities, the ionopause height positions determined with the satellites Venera-9, 10 on the one hand and Pioneer-Venus orbiter on the other hand are in good agreement. This fact testifies to the reliability of the experimental dual-frequency radio occultation data. An attempt to compare the radio occultation data with the direct measurements points out the essential contradictions between them, which need detailed analysis and discussion. 相似文献
445.
446.
Cole S.N. Sjoberg E.S. Fanuele M.A. Rittenbach O.E. Olesch R.G. 《IEEE transactions on aerospace and electronic systems》1979,(5):594-599
The environment and radar operation simulator (EROS) is a hardware system whose function is to produce realistic synthetic radar backscatter, incorporating both target and clutter. The simulator is electrically connected to a subject radar and responds in real time to the radar's antenna scan angle by producing the correct composite video signal. 相似文献
447.
Charge exchange lifetimes for ring current ions 总被引:1,自引:0,他引:1
In applying the charge exchange mechanism to ion phenomena within the Earth's magnetosphere it is critical to the proper interpretation of observations that the charge exchange lifetimes for the ions be known as accurately as possible. Various new results have been published which significantly modify the charge exchange lifetimes which have been used in space physics research during the past decade and a half. Some of the newer results have been used in the application of the charge exchange decay mechanism but the use has been limited and for the most part incomplete. The neutral hydrogen density distribution now yields lifetimes which are shorter than previously calculated, while the functional dependence of the lifetimes on pitch angle provides for slower decay for ions mirroring off the geomagnetic equator. This review coalesces and summarizes the latest and best measurements of the physical quantities involved in the complete calculation of the charge exchange lifetime of the mirroring magnetospheric ions. 相似文献
448.
Thin-film rechargeable Li-LiMn2O4 batteries have been fabricated and characterized. Following deposition by electron beam evaporation of LiMn2O4, the amorphous as-deposited cathode films 1 cm2 in area by 0.3to 4-μm thick were annealed at 700°C to 800°C in oxygen in order to form the crystalline spinet phase. The specific capacity of the cells between 4.5 V to 3.8 V ranged from 50 μAh/mg to 120 μAh/mg. When cycled over this range, the batteries exhibited excellent secondary performance with capacity losses as low as 0.001% per cycle. On charging to 5.3 V, a plateau with a median voltage of 5.1 V was observed. The total charge extracted between 3.8 V to 5.3 V corresponded to about 1 Li/Mn2 O4 相似文献
449.
J.M. Malherbe G. Simon P. Mein N. Mein B. Schmieder J.C. Vial 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(11):53-56
Disappearances of preflare filaments have been observed on June 22, 1980 (S07,W13) (flare at 13.04 U.T.) and September 3, 1980 (flare at 7.52 U.T.). The analysis of MSDP data (MEUDON) leads to the followings conclusions : - Disappearances begin a few minutes before the Hα impulsive phase. - The filaments can be seen again after the flares. - Upwards motions occur in several points, without disturbing significantly preëxisting downflows.Velocity maps suggest shears or velocity loops.The filament disappearance seems to be due to a heating mechanism beginning before the flare maximum. 相似文献
450.
The theoretical basis and methods of implementation of a moment algorithm for the range separation estimation of two closely spaced point targets are presented. Moment estimation and noise filtering techniques introduced here result in a considerable improvement over Baum's algorithm. The error bounds are established and it is shown that the spectral moment estimator exhibits optimum (zero bias, minimum variance) performance when the target separation normalized to the standard deviation of the Gaussian pulse is 2?1.5. Monte Carlo simulation is performed to verify the approximations made and to demonstrate the feasibility of the working models. 相似文献