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91.
Par Marjan Čadež 《Pure and Applied Geophysics》1965,61(1):232-245
Summary In the paper it is shown in which manner the cooling of the air due to the melting of snowflakes causes the appearance of special air masses of greater or smaller dimensions. Here some examples are given of the formation of such air masses of melting in Yugoslavia on the north slopes of the Dinarian Alps.
Zusammenfassung In dieser Arbeit ist gezeigt, auf welche Weise die Abkühlung der Luft, die durch das Schmelzen der Schneeflocken bedingt ist, besondere Luftmassen von grösseren und kleineren Ausdehnungen zur Folge hat. Es sind einige Beispiele von solchen Luftmassen des Schmelzens in Jugoslawien gegeben, die auf der Nordseite der dynarischen Gebirge formiert sind.相似文献
92.
Summary A simple two-dimensional quasi-geostrophic linearized model of the atmosphere is used to investigate the behaviour of the quasi-geostrophic modes for five horizontal rectangular grids. Numerical expressions for frequencies of Rossby waves for all grids are evaluated. It was found that the B and C grids produce only negative frequencies as well as the continuous case. The D grid has negative and zero frequencies. Finally, it was found that the A and E grids produce positive frequencies and eastward moving Rossby waves.With 2 Figures 相似文献
93.
Karel Pěč Jana Pěčová Oldřich Praus Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1977,21(3-4):383-393
n ¶rt;a, n¶rt;mau 531 au ¶rt; u aum m u¶rt;uu n mumu ana¶rt;, ¶rt; u -m n, aauum ¶rt;um u u amuaa n¶rt;naa ma ua aama. uu nmam an¶rt;u ¶rt; u aum aam ¶rt;au cuu uP
n
m
, n¶rt;am mn n=1, 2, 3 u 5 (m n). u uua ¶rt;a¶rt;amu uu n¶rt;mauu uum au (a. 1) u u n aumam uu nmu, m n¶rt;mam u¶rt; am uuu ¶rt; u aum (u. 1–4). annuau 2
u 5
mn nm ma am mmmu m (u. 5, 6). ama uuu u m aam amu uu uma. 相似文献
94.
Summary Results of computing the anomalies of the variable magnetic field, generated by a harmonically variable field of the H1,0-type in the model of a spherical Earth with an expressive bulge in the well-conducting part of the mantle, are presented. It was found that not only the radial, but also the tangential component of the magnetic field is disturbed above the bulge. The largest amplitudes of these changes can be observed over the area of the largest slope of the conductivity boundary if the exciting magnetic field is perpendicular to the surface of the interface. 相似文献
95.
Summary As a result of investigating the energy flow, transmitted by short-period HM waves, the existence of a frequency limitation was found at the theoretical investigation of the propagation of these HM waves. 相似文献
96.
We propose a new formal definition of discovery for a Solar System object. It is based on an objective and mathematically
rigorous algorithm to assess when a set of observations is enough to constitute a discovery. When this definition is satisfied,
in almost all cases the orbit is defined well enough to establish the nature of the object discovered (Main Belt vs. Near
Earth Asteroid, Trans-Neptunian vs. long period comet). The frequency of occurrence of exceptions is estimated by a set of
numerical experiments.
The availability of a non-subjective definition of discovery allows some rules to be adopted for the assignment of discovery
credit with a minimum risk of dispute. Such rules should be fair, encourage good practice by the observers and acknowledge
the contribution of the orbit computers providing the identifications and the orbits, as well as the one of all the contributing
observers. 相似文献
97.
98.
B. Novaković K. Tsiganis Z. Knežević 《Celestial Mechanics and Dynamical Astronomy》2010,107(1-2):35-49
In this paper we present a comprehensive analysis of the dynamics in the region of the (3556) Lixiaohua asteroid family. The family lies in a particularly interesting region of the phase space, crossed by several two-body and three-body mean motion resonances. Also, members of this family can have close encounters with large asteroids, such as Ceres. We have identified the mean motion resonances which contribute to the long-term dynamical evolution of the family and our results confirm that the members of this family can be classified into a number of groups, exhibiting different dynamical behavior. We show for the first time that in the Lixiaohua region, apart from the chaotic diffusion in proper eccentricity and inclination (e p and I p ), there is at least one extended chaotic zone where several resonances overlap, thus giving rise to chaotic diffusion in proper semi-major axis (a p ) as well. Using a code of Monte Carlo type, we simulate the evolution of the family, according to the model which combines the chaotic diffusion (in a p , e p and I p ), Yarkovsky/YORP thermal effect and random walk in a p due to the close encounters with massive asteroids. These simulations show that all these effects should be taken into account in order to accurately explain the observed distribution of family members in the space of proper elements, although a “minimal” model that accounts for chaotic diffusion in (e p , I p ), Yarkovsky-induced drift in a p and random walk in a p due to the close encounters with the most massive asteroids is enough to grossly characterize the shape of the family. 相似文献
99.
A. Sajnović K. Stojanović G. S. Pevneva A. K. Golovko B. Jovančičević 《Geochemistry International》2010,48(7):678-694
This paper reports an investigation of 60 samples of lacustrine sedimentary rocks of Neogene age lying at depths of 0–400
m in the Valjevo-Mionica Basin, Serbia. The goal of the study was to determine the origin and type of primary organic matter
(OM), the degree of thermal alteration, the generation potential of OM from the rocks of this basin, and conditions in the
sedimentation environment during the formation of the rocks. The potential of OM of the rocks was estimated on the basis of
the thermolysis of a representative sample after its preliminary debituminization. 相似文献
100.