共查询到20条相似文献，搜索用时 93 毫秒
1.
N. D. Mtundu R. W. Koch 《Stochastic Environmental Research and Risk Assessment (SERRA)》1987,1(2):101-116
The dynamics of water within the unsaturated root zone of the soil are represented by a pair of stochastic differential equations (SDE's), one representing the so-called surplus state of the moisture and the other the deficit condition. The inputs to the model are the climatically controlled random infiltration events and evapotranspiration which are modeled as a compound Poisson process and a Wiener (Brownian motion) process, respectively.The solutions to these SDE's are not in close-form but sample functions are obtained by numerical integration. The moment properties of the soil moisture evolution process have also been derived analytically including the mean, variance, covariance and autocorrelation functions.To illustrate the model, climatic parameters representing the surplus and deficit cases and properties of clay loam soil have been used to numerically derived the corresponding sample functions. With proper selection of all the parameters, physically realistic sample trajectories can be obtained for the model. 相似文献
2.
Justus Rosenhagen 《Ocean Dynamics》1949,2(1-3):102-107
Summary It is suggested to identify civil twilight only with a distinct range of the intensity of global illumination according to practical needs (i. e., in case of cloudiness, independent of astronomical data), whereas astronomical twilight means the whole interval between the sun's altitudes of 0° and –17°. 相似文献
3.
The response of the critical frequency of the ionosphere F2–layer, described by its main Fourier components (daily constant, diurnal and semidiurnal waves) and the lower thermosphere dynamics to the geomagnetic storms in July 1991 and February 1992 is studied. The daily constant displays a negative response, however, the magnitude of reaction depends on the season and latitude. The amplitudes of diurnal and semidiurnal waves increase during a geomagnetic storm, as this enhancement is very strong at high latitudes in winter. The prevailing neutral wind, especially the zonal wind, shows an inclination to decrease during the geomagnetic storm (the effect is more distinct in summer). The amplitudes of diurnal and semidiurnal tides also demonstrate a tendency toward reduction during high geomagnetic activity. 相似文献
4.
Ludmila Třísková Pavel Šroubek Igor S. Veselovskij 《Studia Geophysica et Geodaetica》1992,36(1):57-59
Summary The vortex flow pattern in the outer heliosphere is calculated on the basis of hydrodynamical equations. Quantitative solution in cylindrical coordinates is used. Moving vortices may be formed due to the heliolatitudinal solar wind velocity dependence and nonstationary boundary conditions near the Sun. The flow pattern consists of a system of cyclones and anticyclones. 相似文献
5.
F. Errulat 《Ocean Dynamics》1951,4(4-6):185-185
Summary With a view to avoiding the well-known discrepancy in the physical and earth magnetical denomination of the earth's magnetic poles it is suggested to call them henceforth arctic magnetic pole and antarctic magnetic pole.
Propos relatif à la dénomination des pôles géomagnétiques
Résumé Tenant compte de la discordance entre la dénomination scientifique des pôles magnétiques de la terre et celle qui est habituelle l'auteur propose de les nommer pôle magnétique arctique et pôle magnétique antarctique.相似文献
6.
aamuam uu am a (m u naamuu n) u u (a) uu a uu mu uu. mam (19), (28) naam, m amua am mau u m ¶rt; am amu: a) na ¶rt;um am, n n a uu am u uu a uu; ) ma ¶rt;um am, m aam uu a uu. 相似文献
7.
Summary The motion of particles in a turbulent flow is described by means of algebraic physics. The initial concepts are structurally ordered groupoids, algebras of observables, logically dependent on them, with couplings and the non-canonic transition between two Hamiltonians. The non-canonic transition leads to the substitution of time t by a new parameter. Its real counterpart gives the lower limit of the size of the time step in the differential equation of transfer, based on the semi-empirical image of turbulent diffusion.
uu amu mm muu nua ¶rt;mau aau uuu. ¶rt;u nmuu m mm n¶rt;nnu¶rt;, uu m u auu a a¶rt;a u u auu n¶rt; ¶rt; ¶rt;aumuaau. auu n¶rt; nu¶rt;um a u t naam. ¶rt;mum aa n¶rt;m uau aa am au na, nua a nnuu au mm ¶rt;uuu.相似文献
8.
Dr. James R. Wait 《Pure and Applied Geophysics》1954,28(1):47-56
Summary The radiation fields of a vertical electric antenna situated on a horizontally stratified ground are discussed. The attenuation and wave-tilt of the surface wave and the height-gain factor are shown to be a function of the horizontal stratification in the ground. It is possible that the results have application to an airborne geophysical exploration scheme. 相似文献
9.
Marta Krsová Miroslav Krs Petr Pruner Richard Chvojka Reviewer V. Kropáček 《Studia Geophysica et Geodaetica》1989,33(4):338-361
Summary Porcellanites and palaeo-slags from North Bohemia are natural materials which can be used to derive the palaeomagnetic directions and palaeointensity of the geomagnetic field active at the time of caustic alteration. The origin of these rocks, called erdbrands, was due to the caustic alteration of predominantly pelitic sediments as a result of underground fires conditioned by spontaneous ignition of coal seams. The caustic alteration occurred during the Upper Pliocene to the Quaternary. Three procedure based on the methods by Thellier and Nagata are presented in the paper. The newly developed apparatus MAVACS (Magnetic Vacuum Control System) was used for the thermal demagnetization of samples. A procedure based on multi-component analysis was also proposed and tested. Besides some methodic results, it was found that the geomagnetic field intensity varied during the respective period within the limits of 48%±4% to 154%±32% of the present geomagnetic field intensity.
aum u na au a mumuu uu n¶rt;mam nu¶rt; amua, m n¶rt;¶rt;um ¶rt; ¶rt;u naaum anau u naumumuaum n, ¶rt;m amu uu. mu n¶rt;, aa ¶rt;a¶rt;, uu n¶rt; uu amu uu num num a¶rt; n¶rt; ¶rt;mu aau . amu uu u m nu¶rt; m nua ¶rt; mmu nu¶rt;a. am n¶rt; mu umnmau nua, n¶rt;¶rt;u ¶rt; ¶rt;u naumumu, nuau a m¶rt; u aama. a aamaa annaama MAVACS (Magnetic Vacuum Control System) a unaa ¶rt; mu aauuau ¶rt; amu aa. n¶rt; u n n¶rt;¶rt;, a a munm aau amuauu. nu m¶rt;uu au, ma ma, m umumaum n u¶rt; nu¶rt; a n¶rt;a 48%±4%-154%±32% au umumu aum n.相似文献
10.
Summary The data on geopotential heights and temperatures at 7 pressure levels between 1000-10 hPa above Berlin(52.5 °N, 13.4 °E) are analysed for the winters of 1963–1973. No demonstrable effect of the interplanetary magnetic field sector boundary crossing (IMF SBC) is found in the lower and middle stratosphere, but there is a demonstrable effect in the middle troposphere at the 500 hPa level. This effect is less important than the IMF SBC effect in the tropospheric vorticity area index and seems to be of a different type.
auum ¶rt;a nnmua m u mnam a 7 nm ¶rt;au ¶rt; 1000-10 a a¶rt; u(52,5 °.., 13,4 °.¶rt;.) ¶rt; u 1963–1973. ua ¶rt;aam m nu mau nam aum n( ) ¶rt;a amu u u ¶rt; mam, ma m a¶rt; ¶rt; mn a 500 a. mm m a, m u¶rt; na¶rt;u aumu am, u am m ¶rt; muna.相似文献
11.
Summary The existence of global synchronous atmospheric oscillations with the period of about 1.4 hour is indicated in terms of a simple theoretical model of the circumpolar circulation.
u nu nm mmu ¶rt;u un uuu naa maua au am nu¶rt; 1,4 .相似文献
12.
auam aum¶rt;, m u n¶rt; n a¶rt;u u nm a anu, umua a u mauu u 1964–1976
. ¶rt; aum¶rt; ma auau aum¶rt;, n¶rt; uu m . 相似文献
13.
u u u u uu smu um ¶rt;um ¶rt; a, s¶rt;a ¶rt;a ¶rt;u suu (n — mn, k — n¶rt;): saumauo n u: n=2, k=0; n=2, k=2; n=3, k=0, 1, 2, 3; n=4, k=0; n=4, k=3; saumau n : n=2, k=0; n=2, k=2; saumau n a: n=2, k=0.
Dedicated to Prof. RNDr. Emil Buchar, DrSc., Corresponding Member of the Czechoslovak Academy of Sciences, on the Occasion of His 75th Birthday 相似文献
Dedicated to Prof. RNDr. Emil Buchar, DrSc., Corresponding Member of the Czechoslovak Academy of Sciences, on the Occasion of His 75th Birthday 相似文献
14.
¶rt;au uu aum nuuumu u aumnuu ¶rt; aa aam n¶rt; am amuu u namuu ¶rt;au. amu uu aumnuu nuuumu, a amu ¶rt;au, m ¶rt;mu au ma nma aaumu m¶rt; ¶rt;a, m a amu uu aum m mnu n¶rt;u ¶rt; mm uaum amua n¶rt; ¶rt;au. u aumnuu nu a namu ¶rt;auu(<1%) a uuu m nuuumu i uaum amua. u aumnuu ¶rt;mu uu uum aauuau ¶rt;ua am m uu, m, m ¶rt; u au namu ¶rt;auu. 相似文献
15.
S. P. Burlatskaya Václav Bucha Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1972,16(4):407-410
a n¶rt;u¶rt; amuu amua uuu anmuaum n a n¶rt;u 8500 m nm um au aam m uuu m naama. ¶rt;u u ¶rt;a ¶rt; u ¶rt; m¶rt; mumu auu nau nuu aau mama [1–3] (Puc. 1.B). nma aau auau (Puc.2) mnaua m m m¶rt;a, ¶rt; au n¶rt; amu u, m n¶rt;u 2- ma m, mmu naa auu nu¶rt; n¶rt;a 1000 m u 350 m, au a aumu, mmm 80%- mmu. am au ¶rt;a u anmu ¶rt; m¶rt; mumu (mum) naa auu u¶rt; ma u ¶rt; m naama[5] (Puc. 3). uma a mam nma aaua naaa auu nu¶rt; n¶rt;a 750 m, 200 m u a — 300 m. (Puc. 4.) nmu u ¶rt;a nma amua an¶rt;u n¶rt;u n u ma m (au) auumu m ¶rt;m m (Puc. 5). aa a m¶rt;m nu naamaum n aam ¶rt;uu mu au, anum¶rt;a m uua nm m¶rt;a.
Dedicated to Academician Alois Zátopek on His 65th Birthday 相似文献
Dedicated to Academician Alois Zátopek on His 65th Birthday 相似文献
16.
Summary On the basis of the conservation of the Earth-Moon angular momentum, the period of the Earth's resonance rotation and Moon's revolution and the relation between tidal deceleration of the Earth's rotation and of the Moon's mean motion are derived theoretically. The comparison of the theoretical relation with the observed values indicates that a mechanism should exist which decreases the maximum principal moment of the Earth's inertia bydC/dt=–3.2×1029
kg· . m2 cy–1.
¶rt; u au ma uma ¶rt;uu um -a, ¶rt;am mmuu ¶rt; a nu¶rt;a au u u uma ¶rt;uu u mu nuu u mu au u u ¶rt; ¶rt;uu . aua mmu mu a¶rt;au auu, ¶rt;am au, m ¶rt; um m u aua ma uuu udC/dt=–3,2×1029 2 (mmu)–1.相似文献
17.
¶rt; aau ua au u¶rt;a, umu a nmu m-10 n uum mau mu n (). am au ¶rt;uana amm. aa ¶rt;¶rt;auma umnmau uuu u, auau nu ua au u¶rt;a. 相似文献
18.
Summary An attempt is made to show possible ways of predicting radio wave absorption in the midlatitude lower ionosphere using relations between absorption and the intensity of solar ionizing radiation and/or common solar activity indices, and between absorption and f0F2.
aa mu nuau nu a¶rt;u ¶rt;um u u a mu ¶rt; nu u umum uuu uu (uu uu u¶rt;au amumu) u ¶rt; nu u f0F2.相似文献
19.
Summary The new, more reliable data on transmisson function of the atmosphere in the region of 12–18 carbon dioxide absorption band are obtained. The radiation chart for calculations of atmospheric heat radiation is built on the base of this data. The dependence of atmospheric heat radiation on CO2 and H2O contents and also on temperature vertical distribution is investigated with the help of the radiation chart. It is shown, that the heat radiation of the atmosphere almost doesn't depend on variations of carbon dioxide content in the atmosphere. The income of atmospheric heat radiation in the region of spectra from 12 to 18 in integrated atmospheric radiation is determined.
, 12–18. . , . , . 12–18 .相似文献
20.
Summary The hypothesis of an expanding Earth is discussed on the basis of lunar laser ranging It is provcd that the given data do not indicate a secular increase in the principal moment of the Earth's inertia which would have to occur if the Earth were really expanding.
¶rt;amunma au u mu u ammuu a¶rt;u u ¶rt;a n a auu . aam, m n mu ¶rt;a m umamu amaua ma uuu u, m ¶rt; nmmam auu, u n¶rt; u m.相似文献