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1.
Zoran Knežević 《Celestial Mechanics and Dynamical Astronomy》1993,55(4):387-404
Leverrier's development of the indirect part of the disturbing function has been extended to include terms up to degree 4 in eccentricity and inclination; the resulting series has been expressed with respect to a fixed plane, and in a computer readable form (a list of integers). Tests have been performed for the relative significance of the terms of degrees 2, 3 and 4, and estimates have been obtained for the accuracy of the short periodic perturbations of a minor planet, and of the corresponding mean orbital elements. It was found that: (i) even in extreme cases, the indirect part of the disturbing function gives rise to very small short periodic perturbations; (ii) bodies of very high eccentricity/inclination and those close to mean motion resonances are most significantly affected; (iii) indirect perturbations for minor planets can be computed up to the degree 2 terms only, without any significant loss of accuracy; and (iv) higher degree indirect perturbations appear to be important only for their contribution to the long periodic effects of higher order (with respect to the perturbing mass). 相似文献
2.
介绍一种自行设计和加工的直接雾化石墨炉进样装置的结构、工作原理和操作方法。该装置由微机控制与石墨炉加热程序同步工作,可以实现自动控制和自动测量。对雾化进样石墨炉分析的仪器参数和实验条件进行了研究和选择。结果表明,该装置与石墨炉结合具有自动化程度高、重现性好、样品利用率高和分析速度快等特点。 相似文献
3.
J. Rajchl J. Bočcek D. Očenáš J. Škvarka P. Zimnikoval H. Murayama K. Ohtsuka 《Earth, Moon, and Planets》1995,68(1-3):479-486
Some results following from two contemporary photographical programs (Slovakia and Japan) for persistent meteor train spectra are compared. It shows that even though both programs are not too different according to their lenses and films used, the spectral interval detected is very different. In this respect prism as a dispersion element is more favourable than the grating with blaze wavelength near 610 nm. However, some results previously assumed as typicai for presented persistent trains-e.g. the forbidden Herzberg O2 emission, the NO2 continuum and OH red emissions-seem to be substanciated especially due to higher and linear dispersion of those grating spectra. 相似文献
4.
The behaviour of the flare in the period of enhancement and maximum of hard X-ray, microwave and decimetric type IV continuum is analysed. The elongation of the H ribbons and microwave source disclose that the energy release site was shifting through a system of loops with a velocity less than 200 km s-1, and that the energy was carried down the field lines with a velocity of about 1000 km s-1, implying the thermal conduction front mechanism of energy transport. Several processes of energy release are considered and it is concluded that an explanation in terms of succeeding interactions of neighbouring loops, involving fast reconnection of their poloidal components is in best agreement with the observations.Proceedings of the Second CESRA Workshop on Particle Acceleration and Trapping in Solar Flares, held at Aubigny-sur-Nère (France), 23–26 June, 1986. 相似文献
5.
A. Čadež 《Astrophysics and Space Science》1985,109(2):399-402
We respond to comments made in a recent letter by Karimet al. (1984), and show that the examples of interstellar absorption at2800 Å that they have presented so far can all be attributed to overexposure of the IUE detectors. 相似文献
6.
Singh et al (2005) examined the potential of the ANN and neuro-fuzzy systems application for the prediction of dynamic constant of rockmass.
However, the model proposed by them has some drawbacks according to fuzzy logic principles. This discussion will focus on
the main fuzzy logic principles which authors and potential readers should take into consideration. 相似文献
7.
M. Čadež 《Pure and Applied Geophysics》1960,47(1):172-182
Zusammenfassung Man beobachtet Antizyklonen, die als Folge einer Konzentration von Kaltluftmasssen auf ein kleineres Gebiet gedeutet werden können. Die Konzentration der Kaltluft ist durch die Umwandlung der kinetischen Energie der Kaltluft in potentielle Energie oder durch die Wärmezufuhr der kalten Luft bedingt. Solche Antizyklonen bilden sich oft in Berggebieten, da dort wegen der grossen äusseren Reibung die erwähnte Umwandlung der Energie beschleunigt wird. Wie gross solche antizyklogenetischen Effekte sein können, ist berechnet.
Summary The origin of some anticyclones can be explained as a consequence of the concentration of the cold air on a smaler area. The concentration of the cold air is caused by a transformation of the kinetic energy of the cold air into the potential energy or by the heating of the cold air. Such anticyclones often appear in mountain regions where the transformation of the mentioned energy is more intense. The intensity of such anticyclogenetical effects is evaluated.相似文献
8.
Antonín Papež 《Studia Geophysica et Geodaetica》1964,8(2):200-204
Резюме Дабление воздуха, переснитанное иа уровень моря по стандартной атмосфере в Q-коде обозчачается через QNH. Давление воздуха
пересчитанное на уровень моря по высотной барометрической формуле обознаеается через QFF. Для целей авиационной службы погоды
должны быть известны значения QNH, однако Зе барическое поле на синоптических картах выражается через QFF. С помощью рис.
1 для соответствующей температуры воздуха на станцин и ее высоты н. у. м. можно определить разность значений QFF—QNH при давленин
QFF=1000мб. Далее по табл. 2 можно определить поправку для каждого значения QFF отличного от значения QFF при ином давлении, чем 1000мб путем умножения табулированного значения ва разность QFF—1000мб и его алгебраического сложения со значением, полученным по рис. 1.
相似文献
9.
M. Čadež 《Pure and Applied Geophysics》1963,54(1):182-189
Résumé Dans cette étude l'explication de la formation des nuages Ac tra part de la supposition que l'air dans ce type de nuages est plus froid que l'air environnant, ce qui provoque certains courants convectifs dans la région du nuage. Ces courants ressemblent à ceux qui sont supposés par la théorie thermoconvective actuelle. D'après notre avis se trouvent des courants descendants audessous des petits nuages qui composent l'Ac tra, et les petits nuages qui forment l'Ac tra sont des corps séparés dont la température est moindre que la température de l'air environnant: c'est pour cela qu'ils tombent. Au contraire, d'après la théorie thermoconvective actuelle, l'air audessous de petits nuages monte et dans la distribution de la température des discontinuités n'existent pas.
Rapport présenté le 26 Avril 1962 à la Xème Assemblée Générale de laSocietà Italiana di Geofisica e Meteorologia (26–28 Avril 1962) 相似文献
Summary In this paper the explanation of the formation of clouds Ac tra is based on the assumption that the air in the cloud is colder than the surrounding air, causing convective currents in the region of the cloud. These currents are not unlike those assumed by the existing thermoconvective theory. According to the author's view there are descending currents under the cloudlets of which the Ac tra is made, and these cloudlets are separate bodies at a lower temperature than that of the surrounding air, so that the cloudlets fall. On the contrary, according to the existing thermoconvective theory, the air under the cloudlets rises and there are no discontinuities in the distribution of the temperature.
Rapport présenté le 26 Avril 1962 à la Xème Assemblée Générale de laSocietà Italiana di Geofisica e Meteorologia (26–28 Avril 1962) 相似文献
10.
Many formulations have been developed so far to predict the wave height and period from fetch length and wind blowing duration for a constant wind speed. This study aimed to predict wave parameters from fetch length and meteorological factors by using triple diagram methodology based on Kriging principles. Proposed model results were compared with Joint North Sea Wave Project (JONSWAP) model which is used so commonly in the ocean and coastal engineering studies. For the implementation of the methodology hourly wave and wind data were obtained from a buoy located in Lake Ontario. Numerical and graphical comparisons demonstrated that the proposed method outperforms the classical formulation. 相似文献