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1.
am ¶rt; u 12- m 1980. amu¶rt;a um nua n¶rt;.  相似文献   

2.
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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3.
aamuam mam uu mn nma ma-au a. a¶rt; uua¶rt;uma mnam, uuma mnn¶rt;mu u mn nma m ¶rt;uamau au uu uma, n¶rt; m n¶rt; mn nm nu¶rt; a. 2. a u au Q=1,99 u 2,06×10–6 /2 am ¶rt;au mu n ua amu, ma mu (2,5×10–6 a/2 ) aum nam mm ¶rt;uana. um mm am na m¶rt;, ¶rt;¶rt; nu¶rt;m am mam.  相似文献   

4.
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   

5.
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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6.
Summary The optimization of the method of determining the addition constant of an EDM is discussed. The advantages of the optimization procedure from the point of view of efficiency and improvement of accuracy are reported.
nuuu ¶rt; n¶rt;u a¶rt;¶rt;uu n ¶rt;. u nu n u uu u nu u.
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7.
Summary By using a general model of optimum elimination of systematic effects[5], the procedure has been developed for the optimum processing of gravimetric observations affected by the drift in a one-stage net, and statistically justified characteristics of the accuracy of the points of this net have been determined.
u uuu u ¶rt;u nmua uuauu um amuu uu [5] aamaa m¶rt;ua nmua amuaumuu uu ¶rt; aa ¶rt;-man mu; nu¶rt; mamumuu aamumuu mmu m¶rt; m m mu.
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8.
Summary Based on model considerations it is shown that, under certain assumptions, upper cyclogenesis may be expected in the region of the auroral oval as a result of heat released at the time energetic particles of extraterrestrial origin penetrate into the lower stratosphere or even troposphere.
a auu ¶rt; a¶rt;u naa, m nu m n¶rt;nu u¶rt;am u amu aa aa mam ¶rt;u mna nuu muu amu nu¶rt;u u mam uu mn.
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9.
Summary A model, explaining the effect of air pressure changes in the space of the measuring system on the fine dial counter constant of the Worden and similar gravity meters, is presented. It is based on the changes of the bellows volume with compensating the gravity changes. It is shown that the resetting the gravity meter in the whole range has practically no influence on the fine dial counter constant.
u¶rt;a ¶rt;, na m uu ¶rt;au ¶rt;a nmam uum um a nm a umaauma ¶rt; u nuaum. ¶rt; aa a uu a ua umu uma nu nauu uu u mmu. aa, m nma ¶rt;uanaa um namuu um a uu nm a uma.
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10.
Summary The magnetovariational data of 143 stations distributed over the eastern margin of the Bohemian Massif, over the Brunovistulicum and the West Carpathian sector were analysed to obtain transfer functions of the geomagnetic field. Methods of multivariate coherence analysis (spectral domain approach) and of impulse response (time domain approach) were employed. Complex induction vectors were estimated and contour maps of transfer functions were computer generated. Analysing their spatial distribution, we mapped the zones of anomalous induction and interpreted them in terms of electrical conductivity structure with its tectonic implications.
azumauau ¶rt;a 143 n mau an n amu m au z aua, az a umua u ana anam auma n¶rt;am uu zazumz n m¶rt;au zz zmz aaua (nma n¶rt;¶rt;) u unz mua um ( n¶rt;¶rt;). mu mama n u¶rt;u ma u nm am uuu n¶rt;am u. au nmamz an¶rt;u mu aamumu m aa u¶rt;uu, ¶rt; mm ¶rt;uu u n¶rt;a u zz-zuua umnmau.


Contribution No. 105/90, Geophysical Institute, Czechosl. Acad. Sci., Prague.  相似文献   

11.
nua u mam n ma aa ¶rt;mn ¶rt;u aa, ma a n¶rt;a [1]. mma m ¶rt;u aa a ¶rt;auu nauMi (uuuu n) uMa (¶rt;uauu anm), m amm u nu [2–5]. u¶rt;m mam u nu ¶rt;u ¶rt; u¶rt; mu ¶rt; u a ¶rt; ¶rt;a. mu a aa, n¶rt;ua m a aa, nua a¶rt; u u i uu a a¶rt; zi nu nu aa ¶rt; ¶rt;a, m ¶rt;um mua m, a¶rt;u ¶rt; a, ¶rt;m, mnam, anu ¶rt; naa, nm a an u nu. a ¶rt;mn ¶rt;u m n a nu u ¶rt;mn ¶rt;u, ma a ma n¶rt;a [1].  相似文献   

12.
u uuuuaumau uu u m, ¶rt;u a mumau nmu a u nmu mau u nmmu. au n¶rt; nuau ¶rt;mam u u m. nua m¶rt; m u m¶rt;a aau (1960) ¶rt; uu .  相似文献   

13.
au u¶rt;um u mu ¶rt; umu u amu, aa aum, u nuu anmuaum n mu , a ma u n¶rt;nu, m amau uu aum mu u( a a) nnua nu u nam nmama aum mu, aa naam uu . au mmuu mu u a auu ¶rt;a aaua a ¶rt;am a mum uumuu naam ¶rt;a na u ama, n¶rt; a¶rt; uu nu aua ¶rt;nuuaum n mu u. mu ¶rt; num uu, a mmmuu namu naamau , ¶rt; m¶rt; u aua nuu anmuaum n, auam mn uu, a m naama .  相似文献   

14.
Summary The relation of short period PKP1 and PKP2 amplitudes from deep earthquakes in the Tonga region observed at a seismological station in Central Europe, is compared with the theoretical relations computed for different source radiation parameters and depths. The Preliminary Earth Model was used in the computations. Qualitatively good agreement of observed and calculated values was found for the radiation pattern corresponding to the likely geometry of the Tonga subduction zone. The influence of the variation of some source and model parameters on the calculated PKP1 and PKP2 relation is discussed.
¶rt;a au mu anum¶rt; mnu¶rt; PKP1 u PKP2 mu mu a, anua ¶rt; u mau ma n, mmmuu mmuuu uuau, aumau ¶rt; a naam ua umua uu aa. ama unaa ¶rt; PREM. a¶rt; u auma uu ¶rt;am am au ¶rt; a uu, mmm mmuu ¶rt;uu a a. ¶rt;am uu auau naam umu u ¶rt;u a uu am mu anum¶rt; PKP1 u PKP2.
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15.
auam uu ma¶rt;am m¶rt; un ¶rt; nu nm omu mamuu ua. a m n¶rt;aam u aum, m ¶rt; nua a nmuuuam. mm aum ma ¶rt;nam aau maua ua.

Vorgetragen auf dem KAPG-Seminar Geomagnetische Pulsationsindizes, Niemegk//DDR, September 1977.  相似文献   

16.
Summary The effect of the IMF sector boundary crossing (IMF SBC) in the vorticity area index (VAI) — the well-known dip in the VAI after IMF SBC — is found to be independent of the IMF SBC effect in the cosmic ray flux. This finding refutes a recent suggestion by Lundstedt [1] that the IMF SBC effect in VAI is caused by a decrease in cosmic ray flux, but supports the concept of the IMF SBC effects in the ionosphere and atmosphere developed by Latovika [2–4]. Cosmic rays seem to affect the troposphere in another way.
¶rt;mu nu mau nam aum n ( ) a u¶rt; na¶rt;u aumu () — um uu n — a¶rt; auu m ma nm uu . mm mam nam ¶rt;a n¶rt;u ¶rt;m¶rt;a [1], m m a nuu nma uu , n¶rt;¶rt;uam nu m u u am, aum amu [2–4]. am m uu u m um a mn ¶rt;u a.
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17.
ama mam maum n¶rt; n¶rt;um ma u ¶rt;, ¶rt;u ¶rt;unu nu nu au muu u. ¶rt;aa ¶rt; aa a uu au mm ¶rt;uuu n m¶rt;a am. u ¶rt;a n¶rt;aam m ¶rt; muu m nau am u u a um anu u m umu au, m ¶rt;aa ¶rt; a nm n¶rt;um nmam an¶rt;u mauu nu .  相似文献   

18.
19.
Summary The new for measuring the electrical conductivity of rocks and minerals developed in the Geophysical Institute is briefly discussed. Unlike the earlier method it uses a PMD-85-1 microcomputer and related equipment (all of CMEA production), which enable the automatic control of the experiment, collection, evaluation, graphic display and storage of the results. This method is verified by measuring the electrical conductivities of granitoids.
am nua m¶rt; uu mn¶rt;mu n¶rt; u ua ¶rt;a uu umumm . muuu m n¶rt;u¶rt; m¶rt;a unm unmPMD-85-1 u nua¶rt;au nuuu ( nu¶rt;ma ), m nm mm amamu nau numa, , am,au uau u anu mam uu. mm m¶rt; nm n uu mn¶rt;muaumu¶rt;.
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20.
Summary Based on model considerations it is shown that, under certain assumptions, zonalization of tropospheric circulation may be expected in the region of the auroral oval as a result of heat released at the time energetic electrons penetrate from the Sun into the lower stratosphere.
a auu ¶rt; a¶rt;u naa, m nu m n¶rt;nu u¶rt;am auau mn uuu amu aa aa mam ¶rt;u mna nuu mumu m u a u mam.
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