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1.
Summary We search for the effects of the interplanetary magnetic field (IMF) sector boundary crossing (SBC) in upper stratospheric ozone. The SBUV data (Nimbus-7) at the 10, 3 and 1 hPa levels are analysed for latitudes 45° N and 55° N for winters of the period December 1979 to December 1982. An effect of the IMF SBC wos only found at the 10 hPa level. These first results concerning the IMF SBC effect in upper stratospheric ozone are rather preliminary.
¶rt;m uu nu mau () nam aum n () a mam. SBUV ¶rt;a (u-7) a nm ¶rt;au 10, 3 u 1a aauum ¶rt; um 45° u 55° . . ua nu¶rt;a ¶rt;a 1979 – ¶rt;a 1982. m uu a¶rt; m a 10a. mu n mam n uuu a mam m n¶rt;aumu.
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2.
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.
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3.
Summary An approximate method of one-dimensional modelling of the plasma of the Earth's ionosphere is demonstrated for purposes of studying the ionospheric filtration of ULF waves (micropulsations). Apart from the basic local parameters, characterizing the plasma, also derived local characteristics have been defined, i.e. the mass of the so-called effective ion and its effective collision frequency . Drawing on existing empirical models of the mid-latitude ionosphere, vertical profiles (50 km h 1000 km) were determined of the characteristics Ne Ni, ve, and for the daytime and nighttime mid-latitude ionosphere under low and enhanced solar activity, which can be used to study the ionospheric ULF filter.
aa nu uum m¶rt; ¶rt;a ¶rt;uau na ¶rt; u ¶rt; nmm uu u umauu (unau). ¶rt; u mu naamau na n¶rt; mu m aamumuu — aa m. a. mu ua, , u mua amma mu, . a mu nuuu ¶rt; ¶rt;um u u n¶rt; mua nuu (50 h 1000 ) aamumu Ne Ni, ve, u ¶rt; u u ¶rt;u um nu u u amumu. ¶rt;u nam nu uuu u uma.
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4.
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.
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5.
Summary Eight models of the ionosphere in the MHD approximation over the whole range of required heights(50–3000 km) are synthesized on the basis of other theoretical studies and a number of empirical methods for the purposes of modelling the ionospheric filtration of the natural micropulsation (Pc1) signal. The models represent a vertically inhomogeneous and dissipative daytime and nighttime ionosphere of higher latitudes in two regions (L=3 and L=5) of the Northern Hemisphere in summer under low (F 10.7 =70) and high (F 10.7 =200) solar activity. The higher ionosphere (h>200 km) is approximated by a quasineutral oxygen-hydrogen plasma(O +,H +) taking into account the wave-dissipating effects of the neutral component(O, He). The procedure of computing the physical parameters, locally characterizing the medium of the ionosphere, is demonstrated.
a ¶rt;a mmuu am u a nuuu m¶rt; ¶rt;a um u ¶rt; u ( nuuuu) n a m (50–3000 ), m ¶rt; ¶rt;uau u umauu mm unau (1) uaa. ¶rt;u n¶rt;mam m-¶rt; ¶rt;, na ¶rt; u m u u um ¶rt; am (L=3 u L=5) n, uu nu u, (F 10,7 =70), (F 10,7 =200) amumu. a ua (h>200 ) n¶rt;maa nuuuu auma u¶rt;-¶rt; ¶rt;(O +,H +) na, uau nuuam nu u-a ma maQu(O, He). aa m¶rt; uu uuu naam, m aamuu u ¶rt;.
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6.
Summary Rotatory vibrations of a thick spherical shell of isotropic non-homogeneous material with rigidity and density given by (i) = 0 r -2 withQ =Q 0 r -2 e 2mr and (ii) = 0 r m with =Q 0 r n have been discussed and the frequency equation is derived with numerical enumeration of frequency in each case.  相似文献   

7.
Scattering of seismic waves can be shown to have a frequency dependenceQ –1 3–v if scattering is produced by arrays of inhomogeneities with a 3D power spectrumW 3D(k) k –v. In the earth's crust and upper mantle the total attenuation is often dominated by scattering rather than intrinsic absorption, and is found to be frequency dependent according toQ –1 , where –1<–0.5. IfD 1 is the fractal dimension of the surface of the 3D inhomogeneities measured on a 2D section, then this corresponds respectively to 1.5<D 11.75, since it can be shown that =2(D 1–2). Laboratory results show that such a distribution of inhomogeneities, if due to microcracking, can be produced only at low stress intensities and slow crack velocities controlled by stress corrosion reactions. Thus it is likely that the earth's brittle crust is pervaded by tensile microcracks, at least partially filled by a chemically active fluid, and preferentially aligned parallel to the maximum principal compressive stress. The possibility of stress corrosion implies that microcracks may grow under conditions which are very sensitive to pre-existing heterogeneities in material constants, and hence it may be difficult in practice to separate the relative contribution of crack-induced heterogeneity from more permanent geological heterogeneities.By constrast, shear faults formed by dynamic rupture at critical stress intensities produceD 1=1, consistent with a dynamic rupture criterion for a power law distribution of fault lengths with negative exponentD. The results presented here suggest empirically thatD 1-1/2(D+1), thereby providing the basis for a possible framework to unify the interpretation of temporal variations in seismicb-value (b-D/2) and the frequency dependence of scattering attenuation ().This is PRIS contribution 046.  相似文献   

8.
Summary One of the important atmospheric levels, the mean energetic level (MEL), which in a sense reflects the energetics of the whole atmosphere, is defined. Its fundamental properties are shown. In order to describe the MEL correctly a new vertical coordinate is introduced and discussed. The new coordinate, , is defined as the ratio of height and temperature. The MEL is shown to be a level with constant value of . Some incorrect conclusions concerning the MEL, derived in the past, have been corrected.List of symbols used c p specific heat of air at constant pressure - c v specific heat of air at constant volume - e base of natural logarithms - E total potential energy - f Coriolis parameter - g acceleration of gravity - i specific internal energy - I internal energy - J enthalpy - k unit vector pointing upwards - p pressure - Q diabatic heating rate - R gas constant of the air - t time - T temperature - v horizontal velocity - v (3) three-dimensional velocity - w vertical velocity in thez-system - z height - temperature growth rate (T/z) - Pechala's vertical coordinate (z/T) - generalized vertical velocity in the -system (d/dt) - specific potential energy - potential energy - density of the air - Ruppert function - T(1–)–1 - ( ) S quantity at the sea level - ( )* quantity at the MEL  相似文献   

9.
Summary In this paper the quasi-static temperature and stress distributions set up in an elastic sphere by radiation from a point source at a finite distance from the centre of the sphere and out-side it, have been discussed. The temperature boundary condition has been taken in the general form involving an arbitrary function of time. The final solutions have been obtained in terms of series involving Legendre polynomials. Numerical calculations have been done on IBM 1620 Computer and a desk calculator. The results have been represented in graphs.Notation the del operator - u the displacement vector - T the excess of temperature over that at state of zero stress and strain - , Lamé's constants - /2(+) Poisson's ratio - coefficient of linear expansion - 2(1+) - a radius of the sphere - d distance of the point source from the centre of the sphere - d o a/d - K coefficient of thermal conductivity - h heat transfer coefficient of the surface  相似文献   

10.
na ma¶rt;uu n ¶rt;a amamu¶rt;uu ¶rt; una, unu¶rt;a au u m unu¶rt;a — u nua na u n u, m. . nmu, ¶rt; amamu uu.  相似文献   

11.
Summary The influence of the velocity of the movement of the centre of the cycloneV c.c. on the rate of amplitudes' change A/t and periods' change T/t of storm microseisms is investigated. The dependence A/t=k V c.c. and T/t=k 1 V c.c. is obtained. Unmovable depression (V c.c. =0) does not stipulate the change of A/t and T/t.
u V c.c. A/t T/t . A/t=k V c.c. T/t=1 V c.c. . (V c.c. =0) A/t T/t.


Presented as a scientific communication to the IASPEI Assembly in Madrid, Sept. 1969.  相似文献   

12.
Summary The seismic response (the transfer properties) of a model consisting of two layers above a homogeneous halfspace, with curved interfaces and continuously laterally varying velocity within the layers is investigated assuming vertical plane SH-wave incidence from below. The frequency response and the synthetic seismograms are computed by the ray and matrix methods. The dependence of the seismic response on the prevailing frequencies of the incident wave, the role of the individual layers in forming the seismic response, as well as the effect of causal absorption are studied.
aamuam ua au (n¶rt;am ma) ¶rt;u, m u n¶rt;mua ¶rt;¶rt; nnmam ¶rt; , uuuauau a¶rt;a u n u anau m mu , n¶rt;nuu mua na¶rt;a n SH-. amm auu u ummuu a auma u amu m¶rt;au. ¶rt;am auum u auu m na¶rt;a amm na¶rt;a , m¶rt; nu uauu u auu u ma m nu.
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13.
Summary A forecast model to predict the fluctuations of level AT 500 hPa in a selected grid of points is derived. The solution of the compensation equation is sought in the form of a trigonometric polynomial in three idependent variables. It constitutes the basis of a numerical solution of the prediction problem with the use of a high-speed computer. A three-month forecast of the altitude fluctuation of level 500 hPa is evaluated by means of the daily values of the correlation coefficient. The results are satisfactory and the general evaluation shows the model to be prospective.
¶rt;um nmua ¶rt; ¶rt; na au m AT 500a a uum m m. u au nauu um u¶rt; mu mu nua m m auu n. m u u nmu a¶rt;au a . u¶rt;um a m na au m 500a nu nu m au uuma uu. mam m anumu, u nu ¶rt; n¶rt;mam nnmu.

List of symbols used * coupling coefficient between two conjugate atmospheric elements - * ageostrophicity coefficient of the atmospheric system - Coriolis' parameter (=2 sin) - , * geographic latitude, geographic longitude - *, geopotential reference and pressure levels - , * compensation and coupling frequencies - integration field over the entire atmospheric system - A** constant (A*=2 2(*+*)) - A r ,B r ,C r ,D r constants related to subsystem -r- - A s ,B s ,C s ,D s constants related to subsystem -s- - B** constant (B**= 4(*2+2**)) - C r constant (i=1, 2, 3, 4) - E k ,E v ,E p energies of the atmospheric system: kinetic, internal and potential - K transformation constant - m total number of generalized frequencies - R(T) frequency characteristics of the numerical band filter - r0(t),r1(t) daily values of the correlation coefficient - Q heat - x, y coordinates in the reference plane - t time - p 2 Laplace's differential operator in thep-system  相似文献   

14.
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.
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15.
Summary Formulae and numerical estimates are given for the non-periodical variations in the curvature of equipotential surfaces, horizontal forces and directions of the vertical, caused by the decrease in the second zonal geopotential harmonic, by the decrease in the angular velocity of the Earth's rotation and by secular polar motion.
am ¶rt; u ua a nu¶rt;uu uu uu nm, maua u u u ma, a u m aauunmuaa, u mu au u u ¶rt;uu n.
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16.
Summary The geopotential scale factor R 0 =GM/W 0 has been determined on the basis of satellite altimetry as R 0=(6 363 672·5±0·3) m and/or the geopotential value on the geoid W 0 =(62 636 256·5±3) m 2 s –2 . It has been stated that R 0 and/or W 0 is independent of the tidal distortion of surface W=W 0 due to the zero frequency tide.
¶rt;a nmu amumuu u ama amnmuaa R 0 =GM/W 0 =(6 363 672,5±0,3) m u/uu aunmuaa a nmuu¶rt;a W 0 =(62 636 256,5±3) m2 s–2. m, m R 0 u/uu W 0 auum m nm amu a a nuu ¶rt;au nmu W=W 0 .
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17.
Summary The approximate solution for the disturbance of a uniform heat flow in a homogeneous semi-infinite medium by an object of different thermal conductivity buried in it is generally used in the interpretation of heat flow anomalies on the ocean bottom. In order to know the accuracy of the approximate solution, a comparison between the approximate solution and the exact solution is given in the case of a very long horizontal cylinder in a semi-infinite medium. The computed results indicate that the two solutions agree to within 10% whend>1.3 and 0.5<<2, whered is ratio of the depth to the radiusR 0 of the cylinder and is the factor of the contrast of the thermal conductivities between the medium and the body. As for the cases when 1 and 1, the same accuracy can be obtained only whend>2. A similar approach is also applied to the case of a spherical conductor in a semi-infinite medium by using a bispherical harmonic solution. The results of both the bipolar solution and the bispherical solution show that when 1 andd1, the vertical thermal gradient at the surface of the semi-infinite medium is always positive and tends to zero, but a negative vertical gradient may be obtained for the approximate solutions.  相似文献   

18.
Summary The seismic energy released by global earthquake activity with time was correlated with F=||, where || is the absolute value of the change of the Sun's acceleration with time. For deep earthquakes and probability P=0.95, the coefficient of correlation was found to be around 0.4. For shallow earthquakes, the dependence was not proved.
¶rt;a u uu (1900–1982.) ua ¶rt; F=||,¶rt; || am au uu u a. mu (h>60 ) u ¶rt; mmu =0.95 uum uu ¶rt;muam0.45. nm mu auum a n¶rt;m¶rt;a.
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19.
Summary The paper deals with the computation of spherical harmonic coefficients from surface measurements of the magnetic or gravity field of the Earth when the measurements are distributed regularly. The Fourier representation of associated Legendre functions which this procedure makes use of, then enables the harmonic analysis to be transformed to Fourier analysis which has better numerical properties.
ama na ama uu uu uum n nm uu aum uuaumau n u a, ¶rt;a mu uu an ammu ma. ¶rt;mau n a¶rt; , m unm mm n¶rt;¶rt;, nm nmauu aau naam aau , m a¶rt;am uu uumu mau.
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20.
Summary Free vibration of a thick hollow cylinder of non-homogeneous elastic material having rigidity and density varying according to the laws: (i) =0(0+0 z) and Q=Q0(Q0+0 z) for finite and infinite length of the cylinder and (ii) 1/r = and Q = 1/r for finite length only are considered in this paper. Frequency equations are deduced and respective numerical solutions are obtained.  相似文献   

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