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21.
Milan Burša 《Studia Geophysica et Geodaetica》1970,14(1):1-9
Résumé De l'ensemble des coefficients harmoniques du développement du géopotentiel [3, 6, 7], calculé à partir des variations des
éléments orbitaux des satellites, on a calculé les paramètres de l'ellipso?de terrestre triaxial, représentant la surface
du géo?de. La solution fut effectuée par méthode analytique sous la condition du minimum de l'intégrale du carré de l'écart
du rayon vecteur du géo?de et de l'ellipso?de, de même que par calcul numérique à partir des valeurs discrètes 10°×10°.
Address: Politickych vězňů 12, Praha 1-Nové Město. 相似文献
Address: Politickych vězňů 12, Praha 1-Nové Město. 相似文献
22.
Milan Burša 《Studia Geophysica et Geodaetica》1970,14(3):274-285
Summary This paper ties up with [5, 6] the fundamental notations of which have been adopted. The sets of Stokes' constants (harmonic
coefficients) J
n
(k)
, S
n
(k)
were adopted from [4], and the scale factor for lengths, R0=GM/W0, from [5]. The equations for global meridional and parallel sections of the geoid surface W=W0 are formulated. The geoid sections are represented by best fitting ellipses, as regards the meridians always for the arcs
between the equator and the pole.
Address: Politickych vězňů 12, Praha 1-Nové Město. 相似文献
23.
Milan Rieder Miroslav Huka Dagmar Kučerová Luděk Minařík Jiří Obermajer Pavel Povondra 《Contributions to Mineralogy and Petrology》1970,27(2):131-158
Compositions of natural lithium-iron micas are approximated best by the sidero-phyllite-polylithionite join. These micas contain little or no magnesium and manganese. Their octahedral sheets contain close to two trivalent cations (mainly aluminum) in small crystallographic sites and a variable quantity of lithium and R+2 (mainly iron) in large sites. Octahedral vacancies are situated mostly in large sites. Lithium and R+2 approach a 44 replacement relationship in micas with octahedral occupancy close to six. Lithium and fluorine show a good positive correlation (small excess of fluorine over lithium), which indicates a crystallochemical association between them. There is a less distinct positive correlation between lithium and R+4.Based on simplifications, a calculation shows that about two-thirds of octahedral vacancies are caused by substitutions within the octahedral sheet, one-third, by tetrahedral substitutions. Different methods of calculating the crystallochemical formula yield slightly different numbers of octahedral vacancies, but do not affect the mica's position in plots of physical parameters against composition. If a crystallochemical formula is calculated from analysis of a mica contaminated with quartz, topaz, or feldspar, the apparent number of octahedral vacancies increases; such a formula exhibits unusual behavior in composition plots. 相似文献
24.
25.
26.
Summary The mean curvature of the equipotential surface and the vertical gradient of gravity are expressed in terms of a development into a series of spherical harmonics [1, 2, 4], neglecting terms of the order of 10–8. The curvature anomalies have been computed using the satellite data [3]. The symbols used are the same as in [5].Dedicated to 90th Birthday of Professor Frantiek Fiala 相似文献
27.
Burša Milan Kouba Jan Müller Achim Raděj Karel True Scott A. Vatrt Viliam Vojtíšková Marie 《Studia Geophysica et Geodaetica》1999,43(1):1-6
Geopotential values W of the mean equipotential surfaces representing the mean ocean topography were computed on the basis of four years (1993 - 1996) TOPEX/POSEIDON altimeter data: W = 62 636 854.10m
2
s
–2
for the Pacific (P), W = 62 636 858.20m
2
s
–2
for the Atlantic (A), W = 62 636 856.28m
2s–2
for the Indian (I) Oceans. The corresponding mean separations between the ocean levels were obtained as follows: A – P = – 42 cm, I– P = – 22 cm, I – A = 20 cm, the rms errors came out at about 0.3 cm. No sea surface topography model was used in the solution. 相似文献
28.
Milan Stojković Jasna Plavšić Stevan Prohaska Dragutin Pavlović Jovan Despotović 《水文科学杂志》2020,65(3):387-400
ABSTRACTClimate change projections of precipitation and temperature suggest that Serbia could be one of the most affected regions in southeastern Europe. To prepare adaptation measures, the impact of climate changes on water resources needs to be assessed. Pilot research is carried out for the Lim River basin, in southeastern Europe, to predict monthly flows under different climate scenarios. For estimation of future water availability, an alternative approach of developing a deterministic-stochastic time series model is chosen. The proposed two-stage time series model consists of several components: trend, long-term periodicity, seasonality and the stochastic component. The latter is based on a transfer function model with two input variables, precipitation and temperature, as climatic drivers. The Nash-Sutcliffe model efficiency for the observed period 1950–2012 is 0.829. The model is applied for the long-term hydrological prediction under the representative concentration pathway (RCP) emissions scenarios for the future time frame 2013–2070. 相似文献
29.
Milan Burša Jan Kouba Viliam Vatrt Vojtěch Vítek Marie Vojtíšková 《Studia Geophysica et Geodaetica》2000,44(1):1-12
The T/P altimeter data 1993 – 1997 (cycles 11 – 194) has been analyzed with emphases on seasonal variations in sea surface topography (SST). The amplitude of the annual variations amounted to (5.9±0.3) mm when inverted barometer (IB) corrections were applied and (2.0±0.4) mm without any IB corrections. The amplitude of the semi-annual variations in SST was small with IB corrections applied: (0.6±0.3) mm. However, when no IB corrections were applied, it was (1.8±0.4) mm, i.e. the semiannual variations are at the same level as the annual variations with no IB corrections. The phase angle offset of the annual term has shifted by about 180° when IB correction was applied. The dynamics of the ocean-atmosphere system is discussed and it is concluded that it could, at least partly, be responsible for the above observed effects. 相似文献
30.
CUTLASS Finland radar observations of the ionospheric signatures of flux transfer events and the resulting plasma flows 总被引:1,自引:0,他引:1
The CUTLASS Finland radar has been run in a two-beam special scan mode, which offered excellent temporal and spatial information on the flows in the high-latitude ionosphere. A detailed study of one day of this data revealed a convection reversal boundary (CRB) in the CUTLASS field of view (f.o.v) on the dayside, the direction of plasma flow either side of the boundary being typical of a dawn-cell convection pattern. Poleward of the CRB a number of pulsed transients are observed, seemingly moving away from the radar. These transients are identified here as the ionospheric signature of flux transfer events (FTEs). Equatorward of the CRB continuous backscatter was observed, believed to be due to the return flow on closed field lines. The two-beam scan offered a new and innovative opportunity to determine the size and velocity of the ionospheric signatures associated with flux transfer events and the related plasma flow pattern. The transient signature was found to have an azimuthal extent of 1900 ± 900 km and an poleward extent of 250 km. The motion of the transient features was in a predominantly westward azimuthal direction, at a velocity of 7.5 ± 3 km. 相似文献