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1.
mam u¶rt;m uu aumuu a m n uamu ¶rt;u nmu umu ¶rt;ua a maum ¶rt;a amu u. a um naa nu nu naama umuu , au a um aumu m n aau umuu mau aum n. aam, m mum au ¶rt;-amu a ma mu aum u u n a aumu m n.  相似文献   

2.
Summary Localization errors made by approximating a given medium by a homogeneous rectangular block model and due to the approximative solution of two-point ray tracing are estimated for four different structures. The separate influence of the individual characteristics of the medium is discussed. The iterative Geiger method supplemented by a generalized inversion of the damped least-squares and Marquardt algorithm is used for localizating five hypothetical hypocentres using 9 stations. Travel times in the original structures, used as input data for localization, are calculated using a special ray tracing system.
am uu auauu a annuau a ¶rt; ¶rt; ma u ma ¶rt;¶rt; u annuau m a ¶rt; munau nuuum .
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3.
nuam aau ¶rt; amu a um ¶rt; ¶rt;a uauu. ¶rt; ¶rt;a, ¶rt;mu auumu m mnam u nu mum ¶rt;a, umam m ¶rt;u z aa n¶rt; uuu, a aau. u¶rt; auum ¶rt;au z naa m mauu ¶rt; amu, naam, m ¶rt;au ¶rt;z naa zauuam u amu ¶rt;.
Summary A formation of ice particles on artificial deposition INis described. INacting in dependence on the temperature and supersaturation over the ice are considered in the 1 D SSconvection cloud model with detailed microphysics including freezing. The limiting influence of the water vapour pressure upon the concentration of active INis shown resulting from the dependence of water vapour pressure on the ice particle concentration.
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4.
Summary A two-dimensional flow model of an incompressible fluid with constant viscosity has been used to study the changes in the large-scale flow pattern (aspect ratio 4). Implications for convection in the Earth's mantle are discussed.
a ¶rt; mn uuu ua u¶rt;mu nm m unm ¶rt; uu uu mu ama¶rt;a. ¶rt;am mam ¶rt; uu amuu u.
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5.
Summary The application of Maslov asymptotic theory in a general 3-D mixed subspace of 6-D complex phase space is proposed to obtain the integral superpositions of Gaussian packets and beams. The ray method and the superposition of plane waves (Maslov method of Chapman and Drummond [7]) are special limiting cases of the above mentioned approach. The same high-frequency asymptotic expansion formulae for seismic body waves were derived previously in [8] using the Gaussian beam method.
uu aunmmu muu aa m a n¶rt;nmam mu a nmama n¶rt; ¶rt; nu uma nnuu a nam u n. nnuu nu u m¶rt; m nuau n¶rt;u au n¶rt; n¶rt;¶rt;a. a amm aunmmuu u a n m¶rt; a n [8].
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6.
Summary A simple method of calculating fluxes and intensities (both spectral and integral) of radiation in the spectral region 0.29–4 in troposphere and lower stratosphere is proposed. This method allows to calculate with satisfactory accuracy the mean radiative regime of real atmosphere and to solve a wide range of problems both atmosphere-optical and thermal with arbitrary receivers of radiation. ( ) 0.29–4 . , .  相似文献   

7.
¶rt;aam ¶rt;a m¶rt;a amu uaa, u u , u auam u ma mum nuu ¶rt; uau aumma. u n u ama u ma n¶rt; ma m¶rt;a nm a umam u naa u ¶rt; nuu. mm m¶rt; n au auu u aau n¶rt;mam a au nm aum nu m unu a a.  相似文献   

8.
Summary The effect of an irregular contact of two different rock types on the surface heat flow was analysed for the Zlatý Kopec region in northwest Bohemia. The 2-D geothermal model of subsurface structures was compiled according to measured values of the thermal conductivity and heat sources and by using isobaths map of the metamorphite-granite boundary. The heat flow was computed numerically from the temperature distribution obtained as a finite-difference solution of the heat conduction equation. It was found that the heat flow variation, corresponding to the most probable model, amounts approximately to the half of the actually observed changes. The surface heat flow is affected strongly by the thermal conductivity contrast between the overlying metamorphites and underlying granites and, on the contrary, it is little sensitive to the heat production difference between both rock types. It seems, therefore, that, despite the big heat production contrast observed, the main source of the heat flow variability are thermal conductivity inhomogeneities.
¶rt;am uu mama ¶rt; m¶rt; mun n¶rt; a nm mn nm ¶rt; amu am n ana¶rt; uu. a u au mnn¶rt;mu u mnauu u n amu aauauaum — mauu n¶rt; a maa ¶rt;a ¶rt; nunm mm. n nm auma n -am u au mnn¶rt;mu. mam ¶rt;m, m auau mn nma ma a m ¶rt;u, n¶rt;mam nuuum nu a¶rt;a uu. a nm m u um aua mnn¶rt;mu ¶rt; aauu mauuu n¶rt;au u uaauaum, u am, nm a mum auu mnauu ¶rt; muu n¶rt;au. aum, m, m a a¶rt;a au mnauu,a umu auau mn nma m ¶rt;¶rt;mu uma mnn¶rt;mu.
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9.
muu aamuam mauma u¶rt;u, aa uauu n aum n aa , ma n¶rt;mam ¶rt;¶rt; n¶rt;u a. aam, m mam mum au u u ¶rt;a n, a¶rt;am, m a , a¶rt;am n u amm ¶rt;au, ¶rt;a n ( aa um ¶rt;uam). a aamuam u m maua ¶rt;¶rt; aum n a au ¶rt;¶rt; n¶rt; aa. a am uu n Sq auau a m au u u n m mu, m na a, mum a¶rt;a au a¶rt;u mu au u.  相似文献   

10.
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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11.
Summary The algorithm of iterative geophysical tomography is presented. The medium is approximated smoothly by means of B-splines. The tww-point problem of ray computation is solved with the aid of paraxial approximation. The parameters of the medium are obtained from the iterative algorithm of minimizing the quadratic form. Two numerical 2-D examples are given.
u¶rt; au umamuuu mauu. ¶rt;a annuuaa n nu nu -na. ma na aa a nu nu naaua annuauu. aam ¶rt; n a umamu aua uuauauu a¶rt;amu . am nu¶rt; ¶rt;a 2-D u nua.
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12.
Summary Upgoing and downgoing deuteron whistlers were found on VLF records made by Interkosmos 5, 14 and 19 satellites even at heights below 1000 km. To account for them, a slight admixture ofD + ions has been introduced into the ionospheric plasma model with the usual content of only three ion speciesH +,He + andO +. Relations derived for the calculation of characteristic frequencies in a five-component plasma (e,H +,D +,He +,O +) are given as well as the values of characteristic frequencies calculated on this basis. The observed features of upgoing and downgoing deuteron whistlers could be explained by the calculation results, and it is also possible to formulate some conclusions for the purposes of plasma diagnostics.
mu um, anmau a ma u u, u a a nmua m 5, 14 u 19 a ma ¶rt;a 1000 . u u a ¶rt;a ¶rt; u na ¶rt;au uH +,He +,O + aa nuD + u. m mm ua nma ¶rt;a ¶rt; aamumuu amm ¶rt;a ¶rt;u na. uu aamumuu amm nuu um a¶rt;a mu ¶rt;mu um. a m ¶rt; unam aamumuu ¶rt;mu um ¶rt; u¶rt;au naam na.
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13.
nuaa m¶rt;ua u mam unmauaumaGs 12 No. 129 a uauu ¶rt;uana amm 0.02–30. a uu a uau nam auu au u auma naamauma a mua ma u n¶rt;a mumm a ¶rt;uu ¶rt;ama ammau uu .  相似文献   

14.
Résumé On commence par définir le creusement et le comblement d'une fonctionp(, t) du tempst et des points (, ) d'une surface régulière fermée en se donnant, sur cette surface, un vecteur vitesse d'advection ou de transfert tangent à . Le creusement (ou le comblement) est la variation dep sur les particules fictives se déplaçant constamment et partout à la vitesse , A chaque vecteur et pour un mêmep(, ,t) correspond naturellement une fonction creusementC (, ,t) admissible a priori; mais une condition analytique très générale (l'intégrale du creusement sur toute la surface fermée du champ est nulle à chaque instant), à laquelle satisfont les fonctions de perturbation sur les surfaces géopotentielles, permet de restreindre beaucoup la généralité des vecteurs d'advection admissibles a priori et conduit à des vecteurs de la forme: , oùT est un scalaire régulier, () une fonction régulière de la latitude , le vecteur unitaire des verticales ascendantes etR/2 une constante. Ces vecteurs sont donc une généralisation naturelle des vitesses géostrophiques attachées à tout scalaire régulier. Dans le cas oùp(, ,t) est la perturbation de la pression sur la surface du géoïde, le vecteur d'advection par rapport auquel on doit définir le creusement est précisément une vitesse géostrophique: on a alors ()=sin etT un certain champ bien défini de température moyenne.On déduit ensuite une formule générale de géométrie et de cinématique différentielles reliant la vitesse de déplacement d'un centre ou d'un col d'un champp(, ,t) à son champ de creusementC (, ,t) et au vecteur d'advection correspondant. Cette formule peut être transformée et prend la forme d'une relation générale entre le creusement (ou le comblement) d'un centre ou d'un col et la vitesse de son déplacement, sans que le vecteur d'advection intervienne explicitement. On analyse alors les conséquences de ces formules dans les cas suivants: 1o) perturbations circulaires dans le voisinage du centre; 2o) perturbations ayant, dans le voisinage du centre, un axe de symétrie normal ou tangent à la vitesse du centre; 3o) évolution normale des cyclones tropicaux.Finalement, on examine les relations qui existent entre le creusement ou le comblement d'un champ, le vecteur d'advection et la configuration des iso-lignes du champ dans le voisinage d'un centre.Ces considérations permettent d'expliquer plusieurs propriétés bien connues du comportement des perturbations dans différentes régions.
Summary The deepening and filling (development) of a functionp(, ,t) of the timet and the points (, ) of a regular closed surface is first of all defined, in respect to a given advection or transfer velocity field tangent to , as the variation ofp on any fictitious particle moving constantly and everywhere with the velocity . For a givenp(, ,t) and to any there corresponds a well defined development fieldC (, ,t). All theseC fields are a priori admissible, but a very general analytical condition of the perturbation fields in synoptic meteorology (the integral of the development fieldC (, ,t) on any geopotential surface vanishes at any moment), leads to an important restriction to advection vectors of the form: , whereT is any regular scalar, () any regular function of latitude, the unit vector of the ascending verticals andR/2 a constant. These vectors are a natural generalisation of the geostrophic velocities attached to any regular scalar. Whenp(, ,t) is the pressure perturbation at sea level, its development must be defined in respect to a geostrophic advection vector belonging to the above defined class of vectors with ()=sin andT a well defined mean temperature field.A general formula of the differential geometry and kinematics ofp(, ,t) is then derived, giving the velocity of any centre and col of ap(, ,t) as a function of the advection vector and the corresponding development fieldC (, ,t). This formula can be transformed and takes the form of a general relation between the deepening (and filling) of a centre (or a col) of ap(, ,t) and its displament velocity, the advection vector appearing no more explicitly. A detailed analysis of the consequences of these formulae is then given for the following cases: 1o) circular perturbations in the vicinity of a centre; 2o) perturbations having, in the vicinity of a centre, an axis of symmetry normal or tangent to the velocity of the centre; 3o) normal evolution of the tropical cyclones.Finally, the relations between the developmentC (, ,t) of a fieldp(, ,t), the advection velocity vector and the configuration of the iso-lines in the vicinity of a centre are analysed.These theoretical results give a rational explanation of several well known properties of the behaviour of the perturbations in different geographical regions.

Communication à la 2ème Assemblée de la «Società Italiana di Geofisica e Meteorologia» (Gênes, 23–25 Avril 1954).  相似文献   

15.
Summary An effective method of computing wave fields is proposed. It is applicable in regions intermediate to a slowly varying (geometrical optics) and strongly nonuniform medium (full-wave solution).
¶rt;azam mu m¶rt; ama n, nuu nm am ¶rt; ¶rt; (zmua nmua) u u ¶rt;¶rt; ¶rt; (n u).
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16.
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   

17.
m m n¶rt;u mamu [7] m aa uu u aa a¶rt;u uu. uau ¶rt; u m¶rt;mu uu u u, a ¶rt;, u mu n nm. ¶rt;um a ama, ma m u¶rt; nm ¶rt; au ¶rt;amma m um. auu mamu ¶rt;um uua aa ¶rt; m unu¶rt;.  相似文献   

18.
Summary Some regularization approaches to downward heat flow continuation from the Earth's surface to the depth of interest are presented, provided the heat transfer is described by the homogeneous steady-state equation. The Fourier transform of horizontal coordinates is used and the relation between the regularization of the heat flow spectrum and the regularization of the heat flow in the spatial domain are discussed. The utilization of an a priori information about the subsurface heat flow is mentioned.
¶rt; m zuau n¶rt;¶rt; n¶rt;u u nmz mnz nma n¶rt;nuu, m n mna nuam ¶rt;¶rt; maua au (au anaa). na naau zuma ¶rt;uam u ama ¶rt; zuau mnz nma u uau z nma. nma m nuu anu u n¶rt;nmz mnz nma.
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19.
Summary The elements of the VLF chorus, observed simultaneously at a ground station and satellite in polar orbit, can be used to determine the differences in the arrival times of waves and their dependence on latitude. Mostly does not change practically over a wide range of latitudes, however, in some cases it may increase appreciably at low value of L. Model computations of the propagation time, based on the assumption that the source of the chorus is located close to the equatorial plane, have indicated the possibility of explaining the increase in at low latitudes by the presence of a step in the electron density profile close to this plane.
a¶rt;u m a u a um nmu nun um nm n¶rt;um amu u nu¶rt;a ma a u u um auum (L). um a a m ¶rt;uana um, m a a¶rt;am aum uu a a L-a. am anmau n¶rt;nuu amua umua naam m um uu a uu uma auu mnu an¶rt;uu m mauu amua nmu.
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20.
Normal density earth models   总被引：1，自引：0，他引：1  
Summary Models of the Earth's density, close to thePREM model, have been derived, they reproduce the external normal gravitational field of the Earth and its dynamic flattening, and are referred to as normal density models. The Earth's surface is approximated by an ellipsoid of the order of the flattening, or of its square. Of the group of normal models sgtisfying the solution of the inverse problem, the normal density modelHME2 is recommended. The spherically symmetric density modelPREM, which was corrected in the course of solving the inverse problem, thus creating the modifiedPREM-E2 model, was used as the a priori information.
¶rt; ¶rt;u an¶rt;u nmmu uu ¶rt;uPREM (m. a. a ¶rt;u nmmu), aumau n m u¶rt;mu na¶rt;am auaumau n u. m u annuum am unu¶rt; au. uau amu a ¶rt; mam H==0.003 273 994. ma ¶rt; a ¶rt; ¶rt;m ¶rt;HME2. am anu u a ¶rt; nmmu a unaa ¶rt; a¶rt;ua umua ¶rt;PREM. ¶rt;aam ¶rt;uuau m ¶rt;u n¶rt; aauPREM-E2.
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