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921.
Ivanka Charvátová-Jakubcová Jaroslav Střeštík Ladislav Křivský Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1988,32(1):70-77
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.相似文献
922.
Marcela Laštovičková Y. V. Ramana B. S. Gogte Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1988,32(2):222-226
Summary Examination of the relation between electric resistivity, compressional wave velocity and density of Indian Precambrian rocks is presented.
¶rt;m auumu ¶rt; muu nmuu, m n¶rt; uu u nmm ¶rt;uu n¶rt; u ¶rt;uu.相似文献
923.
Summary It has been demonstrated that the observed decrease in the second zonal geopotential harmonic linear in time and the secular decrease in the angular velocity of the Earth's rotation do not satisfy the relation defining the secular Love number k as constant during the whole history of the Earth's evolution. The discrepancy disappears if it is assumed thatdk/dt=–2.4×10–6
cy–1
.
aa, m a ¶rt;a au m aauunmuaa u u a ¶rt;a u mu au u ¶rt;mm mu, n¶rt; u a a nm mu umuu u. a uam, u ¶rt;nmumdk/dt=–2,4·10 –6 (mmu)–1 .相似文献
924.
On the detection of weak strain parallel to the bedding by magnetic anisotropy: A mathematical model study 总被引:2,自引:0,他引:2
Summary Five mathematical models of the superposition of deformational magnetic fabric on sedimentary magnetic fabric are presented.
These models are represented by various combinations of pure shear and simple shear. The diagrams of the variations in the
main magnetic anisotropy parameters with strain can help in recognizing weak ductile deformation in sedimentary rocks.
Реэюме Пруво?rt;umся nяmь мamемamuческuх мо?rt;елеŭ суnерnозuцuu ?rt;еформaцuонноŭ мa?rt;нumноŭ mексmуры на осa?rt;очноŭ мa?rt;нumноŭ mексmуре. Мо?rt;елu ире?rt;сmвaлены в рaзных комбuнaцuях чuсmо?rt;о с?rt;вu?rt;а ц иросmо?rt;о с?rt;вu?rt;а. Дua?rt;раaммы вaрuaцuŭ в ?rt;лaвных naрaмеmрaх мa?rt;нumноŭ aнuзоmроnuu с ?rt;еформaцuеŭ мо?rt;уm nомочь nрu рaсnознaвaнuu слaбых nлaсmuчных ?rt;еформaцŭŭ в осa?rt;очных nоро?rt;aх.相似文献
925.
Jan Pretel Lilian Kiršnerová Reviewer K. Vaníček 《Studia Geophysica et Geodaetica》1987,31(4):390-396
Summary To be able to parameterize vertical heat and water vapour fluxes in the boundary layer of the atmosphere, it is necessary to determined, among other factors, the amount of incident total radiation under a generally arbitrary condition of the atmosphere at any instant of time. This paper deals with a simple model for computing the total radiation based on known solar elevation, total cloud cover and the atmospheric turbidity parameter. This variant of the model was formulated on the basis of a two-year series of total radiation observations made in the radiation network of the Czech Hydrometeorological Institute, and on the measurements and observations made at the observatory of the Institute of the Physics of the Atmosphere in Kopisty. An example of comparing the observed and theoretical values of total radiation will also be given.
¶rt;um naamuauu mua nm mna u amu nzau am mm ¶rt; nu n¶rt;u au a nm numa a a¶rt;uauu m u. mam auam n naamuauu a a¶rt;uauu n ¶rt;a m a, ammu am u mnu az na. ¶rt;azaa ¶rt; nma a mam ¶rt;mu uu auau mu z zu¶rt;mzu z umumma u a amuu mumma uuu am numa. mam ma nu¶rt; nu au u u n n¶rt; ¶rt;u u au a a¶rt;uauu.相似文献
926.
D. Pancheva E. Apostolov G. Nestorov Jan Laštovička Reviewer V. Letfus 《Studia Geophysica et Geodaetica》1987,31(3):301-314
Summary By subsequent application of power spectrum analysis, autocorrelation analysis and fast Fourier transform (FFT) of the day- and night-time absorption values of five LF radio-paths (164 kHz, 155 kHz, 185 kHz, 218 kHz and 272 kHz) in Europe during the interval 1 June 1979–30 June 1980, fluctuations with the following basic (fundamental), commonly recurrent periods were found: 3.5–5 days and 10.5–12 days. They exist in all investigated time series, while 6- and 9-day fluctuations are observed on the northern radio-paths (185 kHz and 272 kHz). Shorterperiod oscillations are most active during autumn and especially during winter, while the longerperiod oscillation (10.5–12-day) has significant amplitudes also in summer.
n n¶rt;am nuu aaua nma mu, amu aaua u m maauu () ¶rt; u ¶rt;a n nu u nmu a¶rt;u ma (164 , 155 , 185 , 218 u 272 ) a¶rt; n nu¶rt; 1 u 1979–30 u 1980. u a¶rt; ¶rt;u (¶rt;ama) nmu nu¶rt;: 3.5–5 ¶rt; u 10.5–12 ¶rt. u nummm u¶rt;a ¶rt;a. 6- u 9-m au a¶rt;am m a¶rt;umaa (185 u 272 ). ama au a amu u u u. ¶rt;nu¶rt; (10.5–12 ¶rt;) um aum anum¶rt; u m.相似文献
927.
Summary The problem of inverting the geopotential series with respect to the geoid radius has been solved. A linearization of the radius powers, making use of a reference surface, has been applied. The body given by the Bruns' formula has been chosen as the reference surface. Corrections to the Bruns' formula in an analytical explicit form have been derived. An internal linearization accuracy of the order of 1 mm has been achieved. The geoid radius coefficients for the GEM-L2 model have been evaluated numerically. The corrections have been found to range from –90 to 90 cm.
m¶rt; uauauu ¶rt; aaumuu u ¶rt; ama a¶rt;ua — ma, m una uum au aumau n u u naam unu¶rt;a. u u¶rt; una um uum u nmuaa u uum au a¶rt;ua — ma. ¶rt;a¶rt;amua ua, aa uauau, n¶rt;a 1 . u¶rt; u am ¶rt; ¶rt;uaumau n GEM-L2. au na nm mm m am nu annuauuu¶rt;a, a a m a, n¶rt;a ± 90 .相似文献
928.
Summary Secular non-tidal variations of geopotential and gravity are estimated due to secular decrease of the second zonal geopotential harmonic, secular polar motion and deceleration of the Earth's rotation.
am a nuu uunmuaa u u u mmu, a u m aauunmuaa, ¶rt;uu n u u mu au u.相似文献
929.
Jaroslava Bošková František Jiříček Reviewer S. Fischer 《Studia Geophysica et Geodaetica》1986,30(2):196-205
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.相似文献
930.
Ivanka Jakubcová Miloš Pick Reviewer V. Kárník Reviewer J. Vondrák 《Studia Geophysica et Geodaetica》1986,30(2):148-152
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.相似文献