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481.
The use of a cosmic potential in relativistic cosmology is criticized. It is pointed out that the energetic closure of the Universe follows from general relativity and from quantized superspace cosmology without the introduction of the cosmic potential. 相似文献
482.
František Jiříček Pavel Tříska O. A. Maltseva E. E. Titova T. A. Yakhnina Reviewer S. Fischer 《Studia Geophysica et Geodaetica》1986,30(4):404-410
Summary The occurrence zone of the VLF chorus in the upper ionosphere appears at L-shells lower than plasmapause position Lpp; with increasing geomagnetic activity the spatial dimension of the zone diminishes, its upper boundary being shifted in correspondence with the plasmapause position, the lower remaining practically without change(L=2.0÷2.5). Calculations of propagation paths have shown that the similarity of the VLF chorus spectrum at different upper-ionospheric latitudes as well as the large spatial dimension of the zone of observation can be explained as special features in the propagation of VLF waves from an equatorial source, starting in the vicinity of the plasmapause with different initial normal angles.
a umauu u ana amu L-, u Lpp (Lpp — nu nana); uu aum amumu nmam a am, nu aua am mmmuu uu nu nana, a u mam namuu u(L=2.0÷2.5). am mamu naam, m n¶rt;u nm a au uma u, ma a nmam ama a¶rt;u, m m mu anmau m amua umua, an amu nana, uu au au.相似文献
483.
E. D. Poezd V. N. Oraevskij Vladimír Fiala Pavel Tříska Reviewer S. Fischer 《Studia Geophysica et Geodaetica》1987,31(2):197-212
Summary The conditions are studied under which ballistic effects of transmission of waves through opacity barriers can be observed in magnetospheric experiments on board satellites. The mechanism of this effect consists of the regeneration of the radiation beyond the barrier by resonance electrons, modulated by a quasimonochromatic wave incident and reflected from the barrier. Ballistic processes in continuously inhomogeneous plasma are studied. Detailed analysis has been carried out for a barrier with a parabolic density profile. Recommendations are presented as to experimental procedures in circumterrestrial space and data processing. The possibilities are studied of observing ballistic effects in the course of active space experiments with sources of intensive broadband turbulence such as beam of charged particles, injected into the magnetosphere.
¶rt;a u, nu m ¶rt; nmu num aum na m a¶rt;am aumuu m n¶rt;u a namu, au m mum auu uu a a au mau, n¶rt;uau auamu , na¶rt;a a a u maa m . am aumuu n na¶rt;¶rt; na. ma u n¶rt; ¶rt; aa naauu nu nmmu. a ¶rt;auu n n¶rt;u numa nmam u n am ¶rt;a. ¶rt;am m a¶rt;u aumuu m ¶rt; amu uu num umuau umu un mmmu, mauu, a nu a amu umu aum.相似文献
484.
Rock magnetic investigations of Permo-Carboniferous carbonate sediments from two areas on Spitsbergen are described, conducted to identify the carriers of the NRM in these rocks. Since microscopic and magnetic separation techniques could not profitably be applied, the nature of magnetic minerals was investigated by thermal demagnetization of the NRM and decay of saturation isothermal remanence (Irs) during heating to 600°C, as well as by the distribution of the median destructive fields of the NRM and observation of magnetic susceptibility after subsequent heatings. The results show that the NRM of these limestones resides mainly in magnetite, but creation of magnetic pyrrhotite and of fresh magnetite is observed during heating to 600°C. Presence of sulphides indicates that magnetite is an oxidation product of pyrite or of non-magnetic pyrrhotite. Examination of rock magnetic properties of limestones leads to the conclusion that most of the magnetite in the rocks of the Bellsund area is of detrital origin, whereas the rocks at Festningen contain magnetite derived from pyrite probably during an early stage of the diagenetic process. 相似文献
485.
J. Siemińska Dr. H. E. Vogel P. Duerst A. Hörler R. Koblet 《Aquatic Sciences - Research Across Boundaries》1970,32(2):591-599
Ohne Zusammenfassung 相似文献
486.
Jaroslava Bošková František Jiříček Pavel Tříska Reviewer S. Fischer 《Studia Geophysica et Geodaetica》1982,26(4):373-380
un nmu a ¶rt;u ¶rt;am ¶rt; mm u a uuuu¶rt; a () a na. m nm, u , ¶rt;um a amm mmu nmua a m m na ¶rt; mum uaum um (2uamm m fH u na amm m fN. uam mm n au ¶rt; amm , ¶rt;mum amu¶rt; f
N
2
f
H
2
u f
H
2
f
N
2
. a m a n¶rt;um umnmau aamumu auauu amm n u nmu a¶rt;u. 相似文献
487.
P. A. Dybczyński T. J. Jopek R. A. Serafin 《Celestial Mechanics and Dynamical Astronomy》1986,38(4):345-356
The methods used so far for determination of the closest approach between two orbits are discussed, and corrected versions of two of them are presented. 相似文献
488.
Mortar Upscaling for Multiphase Flow in Porous Media 总被引:1,自引:0,他引:1
In mortar space upscaling methods, a reservoir is decomposed into a series of subdomains (blocks) in which independently constructed numerical grids and possibly different physical models and discretization techniques can be employed in each block. Physically meaningful matching conditions are imposed on block interfaces in a numerically stable and accurate way using mortar finite element spaces. Coarse mortar grids and fine subdomain grids provide two-scale approximations. In the resulting effective solution flow is computed in subdomains on the fine scale while fluxes are matched on the coarse scale. In addition the flexibility to vary adaptively the number of interface degrees of freedom leads to more accurate multiscale approximations. This methodology has been implemented in the Center for Subsurface Modeling's multiphysics multiblock simulator IPARS (Integrated Parallel Accurate reservoir Simulator). Computational experiments demonstrate that this approach is scalable in parallel and it can be applied to non-matching grids across the interface, multinumerics and multiphysics models, and mortar adaptivity. Moreover unlike most upscaling approaches the underlying systems can be treated fully implicitly. 相似文献
489.
T. Grabińska 《Astrophysics and Space Science》1988,150(1):75-88
Some results concerning the intergalactic dust matter are presented. The results of Tarraro, considered as the first undoubted revelation of intergalactic extinction; and of Zabierowski, treated by him as a trial, seem not to be equivalent. Not experimental data, but their theoretical interpretation is responsible for this non-equivalence.Plates have to be prepared by technically uniform procedures to infer the intergalactic obscuration from pseudo-indices. Significant extragalactic obscuration participates in galaxy correlation function, Rubin-Ford effect, underpopulation of quasars, and Sierpiski's sponge structure of galaxy distribution. Contribution from supermassive pre-stars or Population III to the abundance of elements must be considered as highly plausible. 相似文献
490.
I. N. Garczyńska 《Solar physics》1991,131(1):129-135
The dependence of the maximum height achieved by sprays showing deceleration and stopping at the end of their propagation, on the velocity has been examined. It was assumed that the velocity is greatest at the beginning, so this maximum velocity defines the kinetic energy of each investigated knot at its start. The relation between the maximum height and maximum velocity was examined in 32 knots from 23 sprays. The problem of whether the maximum height achieved by a knot is determined by the gravitational field alone has been studied. The problem of stopping is important especially for knots which have initial velocities higher than the velocity of escape from the Sun. 相似文献