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1.
50 au mn nma a mumuu auu, m ¶rt; aul mmuu uma, a¶rt;au n mu u¶rt;a u uua aauu u mmu. mam naam, m amu mn nma mmmm mu¶rt;a, u a au :  相似文献   

2.
u¶rt;m n uu ¶rt;u m n u ma n¶rt;aa, nu m¶rt;u u ¶rt;uau. n nuu uu ¶rt;u m n ¶rt;a¶rt; nu NoNo VI, VII. u au u n m a (x, H), ¶rt;auu an¶rt;u ¶rt;u m ¶rt; m¶rt; nu, u mua m nuu (H), aamuu an¶rt;u m a mua ¶rt;¶rt; uu ¶rt;uua u a. u a ¶rt;u m (x, H) amm ¶rt;uuu (u) a m¶rt; nu. m¶rt; u, auuu aau, om aamuam muau an¶rt;u ¶rt;u m, uu , n m u m nu aamuu a nmu, am ma a¶rt;am aa uu ¶rt;u m. aa u a¶rt;u n nu NoNo VI u VII u umuu ¶rt;a. mua m nu (H) num m ¶rt;u amu aua u anam um, ¶rt;a amu ¶rt;aua u ¶rt;- nma (nu No VII). ma ¶rt; ¶rt; aua, maa numa nm m u numa nm ma¶rt;um, a unaa nuu umnmauu a¶rt;uu ¶rt;uau amu aua.  相似文献   

3.
¶rt;m n¶rt;u nu nm n m . m¶rt; n¶rt;am nuuu am uma au muna (6) u (10). amua aumnu m m nn unam u u, m nmu ama mm (u. 2). uu nu nm ¶rt;u am mu n¶rt; uua 15mu anau u mu u nn uua mu anau. u unauu m nn ¶rt;u am mu n¶rt; uua ¶rt; 21 anau.

Dedicated to 90th Birthday of Professor Frantiek Fiala  相似文献   

4.
Summary The possibility of solving the stationary heat equation with the convective term is demonstrated in the case that the velocity field of the continuum, and the temperature and heat flow on the Earth's surface are known, and that an assumption is made about the magnitude of heat flows on another part of the boundary of the two-dimensional region being investigated, whereas no boundary condition is imposed on the remainder of the region's boundary. The problem has been solved numerically for a kinematic model of the lithosphere in the region of mid-ocean ridges, based on the assumption of a broad deflected convective flow moving at a distance of more than about 150 km from the ridge modelled as a plate.
aaa m u maua au na mna a, ¶rt;a um n m mua u a nmu u um mnama u mn nm. a ¶rt; amuau aamua ¶rt; amu ¶rt;um n¶rt;nu uu mn nma a a ma amuau a u a¶rt;a. ma na a u m¶rt; a ¶rt; uamu ¶rt;u um amu ¶rt;u-auu m, a a n¶rt;mauu u ma mu nma a amu m ma nau 150 ¶rt;u auma nm.
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5.
a mmuu ¶rt; ¶rt;au nm u , a auauu ma mu au u. aamuam m¶rt; a, ma u mua mu ¶rt;au u ¶rt;aa u uma a; m a mu ¶rt;auu m ¶rt;muam 10% m ¶rt;au, a u nuuau m .  相似文献   

6.
Summary The basic formula used in the presented paper gives the relation between the P wave travel-time perturbation and the perturbation of an inhomogeneous transversely isotropic medium, expressed by four perturbations of elastic parameters and by two angles of orientation of the axis of symmetry of transverse isotropy in space. The travel time perturbation is computed along the ray in the unperturbed inhomogeneous isotropic medium. Four elastic parameters and two angles are parametrized in the model under study and a system of equations for many rays is constructed. The equations are linear in the sought elastic parameters and nonlinear in the sought angles, and the iterative Levenberg-Marquardt algorithm is thus used to solve them. The theoretical 3-D inverse problem was solved in the presented numerical example. The data, simulating teleseismic data, were computed in the direct problem and then inverted. The results indicate the applicability and limitation of the presented algorithm in real problems.
a a, unaa n¶rt;aa am, ¶rt;am mu ¶rt; uu u na u uu ¶rt;¶rt; nn umn ¶rt;, a m nuu naamau u ¶rt; au umauu u umuu nn umnuu nmam. u u na um ¶rt; a aa ¶rt;¶rt; umn ¶rt;. nu naam u ¶rt;a a naamuua ¶rt;u u nma uma au ¶rt; u . au u n um nu naama u u n um a umauu umuu, nm un m umamu aum a-aa¶rt;ma ¶rt; u u. am nu¶rt; ¶rt; m u nu. nu muu ¶rt;a aaa a na a¶rt;aa u am ¶rt;a a. mam naam auu u mu nuu nu¶rt;uma a a.
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7.
Summary The sequence of aurorae, observed at latitudes up to 55° between the years 1001 and 1900 was processed by methods of spectral analysis. The same methods were applied to parts of various duration of this interval. The periods predominant in the time series under investigation were determined. In all the selected parts of the interval, these periods are always located within the same frequency band. Their position is related to the periods corresponding to mutual conjunctions of the large planets.
¶rt; n uu, a¶rt;au a uma ¶rt; 55° nu¶rt; 1001–1900, ama nu nu m¶rt; nma aaua. a n¶rt; ¶rt; am a ¶rt;u m umaa. u n¶rt; na¶rt;au nu¶rt; u¶rt;a ¶rt;a. mu nu¶rt; ¶rt; a am umaa ¶rt;a a¶rt;m ¶rt;ua ¶rt;uaan amm. nu mum nu¶rt;au, mmmuu au u u nam.
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8.
Summary The present paper deals with theZ-model of the nearly symmetric hydromagnetic dynamo as a generation mechanism of the Earth's magnetic field. TheZ-model of Braginsky [2] was solved for viscous core-mantle coupling [3]. It is shown that a similarZ-model can also be constructed for electromagnetic core-mantle coupling, or for both effects combined. A new part of the azimuthal velocity appears in the equations, but the character of the boundary layer is not changed too much. No numerical solution is presented.
mam auam ma aa Z-¶rt; nmu umuu¶rt;aum ¶rt;ua, ma n¶rt;mam amu au aum n. Z-¶rt; au [2] a a ¶rt; a au¶rt;mu ¶rt; ¶rt; u amu. aam, m n¶rt;a Z-¶rt; m m nma ma ¶rt; a maum au¶rt;mu ¶rt; ¶rt; u amu, uu a ma m uuam. au nm a am auma mu, aam nau m. ua u u nu¶rt;um.
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9.
¶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   

10.
n¶rt;m mu ¶rt; mu uau aumma. mu aum u mu u m u mu auauu m¶rt;a. u¶rt;m u naam nm nmmuna uau aumma.  相似文献   

11.
Summary The accuracy of wave field extrapolation is studied with respect to the discretization of field data and integral extrapolator. Assuming a far-field approximation of the Rayleigh-Sommerfeld solution for a two-dimensional scalar wave equation, the minimum and the maximum transmitted frequency are expressed as functions of the sampling intervals t, x, and the half-width x0 and angle a of the migration aperture. The theoretical limitation of the transmitted frequency band is tested on numerical examples.
aamuam mm manuu auumu m ¶rt;umuauu n u uma manu nama. ¶rt; u uma u -¶rt;a ¶rt; ¶rt; a au, ¶rt; nuuuu ¶rt;a n mu ¶rt; uua u aua n¶rt;aa amm a uu m a -nmam ¶rt;umuauu t u , nuu 0 u a a uau anm. mu n¶rt;u amm ¶rt;uanaa mmua a u nua.
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12.
Summary A non-linear model of trochoidal waves is presented which represents a geometrical and kinematical generalization of Gerstner's waves and of the results of[2–4].
¶rt;aam ¶rt; mu¶rt;a , ma m u ma u am[2–4] mu umuu u uamu mm ¶rt;u.
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13.
Summary The distribution of radioactive(Th, U, K), major and selected trace(Rb, Sr, Ba, Y, Zr, V, Cr, Ni) elements of granulites from the Saxonian Granulite Complex was studied. Similarly to the South Bohemian granulites, the Saxonian granulites can be divided according to the contents of their major and trace elements into two main groups, groupA containing mostly acid and subacid granulites (K 2 O>2.5%, SiO 2 >68%), and groupB containing mostly intermediate and basic granulites (K 2 O<2.5%, SiO 2 <68%). Statistically significant differences between groupsA andB were found for all major oxides and several trace elements(Rb, V, Cr, Ni). The Saxonian granulites follow the same calc-alkaline trend as the South Bohemian, granulitesA being placed mostly in the rhyolite field and granulitesB mostly in the dacite, andesite and basalt fields of this trend. The investigated granulites are characterized by a considerable scatter ofTh andU contents accompanied by very variableTh/U ratios; theTh andU concentrations of granulitesA are substantially lower than is usual for rocks of corresponding acidity.
¶rt;a an¶rt;u a¶rt;uamu(Th, U, K) u ua ¶rt;u(Rb, Sr, Ba, Y, Zr, V, Cr, Ni) m aum n¶rt;a aaum na. naa, m u¶rt;aum n uu aam n aaum u ¶rt;u am aua, u u uu. aum n u uu ma a¶rt;um ¶rt; ¶rt;nn; nnA nua¶rt;ama a au¶rt; u au¶rt;aum (K 2 O>2,5%, Si O 2 >68%), nnB ¶rt;u u aum (K 2 O<2,5%, SiO 2 <68%). ¶rt; muunnau mm mamumuu m au ¶rt; a u u ¶rt; m ¶rt;u m(Rb, V, Cr, Ni). auaum n¶rt;¶rt;m um- m¶rt; a u -uaum;aumA a¶rt;ma a uum n, uaumB a a ¶rt;aum, a¶rt;um u aam n m m¶rt;a. ¶rt;aum — u unnA — aamum uu ¶rt;au da¶rt;uamu mTh uU.
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14.
Summary The relation between geomagnetic activity and solar activity is studied in long intervals and in individual 11-year cycles, characterized by certain basic parameters, in connection with investigating the prognostic significance of long-term fluctuations of geomagnetic activity [1, 2]. A number of properties as well as sufficiently close relations with a prognostic significance have been found, such as the secular variation of geomagnetic activity, the 22-year cycle of change in the form of the behaviour of geomagnetic activity in 11-year cycles, long-term concurrence of solar and geomagnetic activity and its changes within the 11-year cycle, relations between solar and geomagnetic parameters characterizing the 11-year cycle.
a auu uu u ¶rt; uaum amum ¶rt;u nma u u m¶rt; 11-mu ua am mu ¶rt; ¶rt;m nuauaum amumu.
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15.
16.
Summary The Gaussian beam method is applied to vertical seismic profiling in 2-D and 3-D models. A simple approach to the computation of Gaussian beam seismograms in the vicinity of structural interfaces is proposed. The effects of (a) the radiation pattern of a point source, (b) noncausal attenuation, (c) transverse inhomogeneities in synthetic seismograms are studied on numerical examples.
m¶rt; a n unm ¶rt; mua u nuuau ¶rt; u m ¶rt; ¶rt;. nmm n¶rt;¶rt; am a mmu mm a¶rt;a. a nua ummuu a uam m (a) uu m umua, () nu nu u () nn ¶rt;¶rt;m.
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17.
Summary For the last two millenia it has been possible to determine the secular variation of solar activity from naked-eye sunspots, aurorae and radiocarbon variations. The results of the analysis of old East Asian observations of comets, which reflect the night cloudiness variation, do not agree with the former findings that the long-term climatic changes derived from comets depend on solar activity. The distinct anticorrelation between the Chinese records of comets and naked-eye sunspots is found only for the period from the 3rd to 6th century A.D., but in other centuries any correlation can hardly be seen. East Asian cometary observations give evidence of climatic changes in different parts of this large geographic region.Secular variations of the River Nile levels, regularly measured from the 7th to 15th century A.D., clearly correlate with the solar variations, which suggests evidence for solar influence on the climatic changes in the East African tropics. The decline of the Kingdoms in ancient Egypt and the occurrence of the Intermediate Periods are generally explained by very low Nile floods and prolonged droughts followed by severe famines and the destruction of the political structure. But the radiocarbon data show that at least the First and Second Intermediate Periods coincide with the secular maxima of solar activity and the Middle Kingdom with the minimum. This contradicts the positive correlation found from the eight centuries of measurements of River Nile levels made by Arabs. It seems that the influence of solar activity on the secular climatic changes has an episodic character.
nu¶rt; uu amumu ¶rt;mam m n¶rt;um nuuum a n¶rt;u ¶rt;a mmu nm au nu n uu u u¶rt;u a nm a¶rt;u¶rt;u uuu. ¶rt; amm nu n uu uu n mmu .. um a m uu ¶rt;a umumuaum n. ¶rt;m auau nu m amum ua a uu amumu a am — am, maau ¶rt;nu¶rt; uamuu uu. ¶rt;a, mam aaua ¶rt;u a¶rt;u m u n a a m am muu ¶rt;au. aua ¶rt;umau anuu ma u u¶rt;u a nma, aum amuu m ¶rt; nu¶rt;a - n 6- , a ¶rt;u nu¶rt;a maa u mmmm. m, aa uu uu mmmu uu ¶rt; ¶rt;au a¶rt;uu m uma, u nuu u¶rt;ummm auuu uu uama au am m au amu.nu¶rt; auauu m n¶rt;a ¶rt; (au), a ma ma aa ma ¶rt; (uu) u n uu, n¶rt;uu u unm ¶rt;u 7- ¶rt; ¶rt;u 15- a, n¶rt;u auau. m u¶rt;ummm uuu a a uamuu uu m-auau mnua. a u u numu aumu ¶rt;unmu am m au ua nuaa. na¶rt; ¶rt;unmu am u amnu ¶rt;amu m uu ¶rt; u u n¶rt;umu aau, a mu n¶rt;a m¶rt; u au numu mm. ¶rt;a, n a¶rt;u¶rt; ¶rt;a aum, m n a n u m ¶rt;amu na¶rt;am ¶rt;umu auau amumu, m nmuum num uu, ¶rt; u ummu uu ¶rt; u. am, m uu amumu a uu uama um aa nu¶rt;u aam.
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18.
Summary The radiation power a VLF loop antenna with an arbitrary orientation of the loop's plane relative to the direction of the external magnetic field is calculated and its portion, transferred to the electromagnetic part of the excited spectrum, is determined.
am umaa m uu am c nu umau nmu uma n m¶rt; a¶rt;um¶rt; n u n¶rt;a ma am mu uu, u¶rt;a ma¶rt;um am am cnma ¶rt;a au.
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19.
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.
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20.
Summary Problems of occurrence of density inhomogeneities in the upper mantle are discussed and their gravitational effects in the region of Central Europe are investigated. Attention is namely devoted to the density contrast between the asthenosphere and the lower lithosphere, and its possible dependence on depth.
¶rt;am n nu nmm ¶rt;¶rt;m amuu u uaumau ¶rt;mu a mumuu ¶rt; n. uau ¶rt;m n¶rt; nmm mam ¶rt; am u um u auumu mu aau.
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