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111.
Ivana Nemešová Nina Klimperová Radan Huth Jaroslava Kalvová 《Studia Geophysica et Geodaetica》1992,36(4):370-375
Summary The results of an objective weather categorization are presented. The 9 meteorological variables recorded daily during winter seasons of 1961–66 at Prague-Clementinum represent the input dataset. The principal component analysis and a few clustering procedures have been evaluated. 5 component solution and the average linkage clustering method were found optimal. The winter days have been grouped, according to their meteorological character, into 14 clusters. The warm categories represent 20% of the time and the cold categories less than 15% of the days. The mean maps of 1000 hPa and 500 hPa are shown for a few selected categories. Clustering techniques applied to long-time instrumental series can provide a better basis for attempting to detect temperature changes which have taken place over a long time span. 相似文献
112.
Summary Some errors of method occurring in A. C. measurements of the electrical conductivity of rocks are discussed. It is demonstrated that the difference between A.C. and D.C. conductivities, at given frequency, depends mostly on the magnitude of the D.C. conductivity and magnitude of the dielectric constant. 相似文献
113.
Summary Indirect phase reflection height measurements have been performed at the Panská Ves Observatory, Czechoslovakia, for 30 years to monitor solar flare effects (SFA). Only after introducing the new receiver in May 1985, could the indirect phase height analysis (IPHA) method be applied to measurements along the Allouis — Panská Ves 162 kHJ measuring path. The IPHA method allows the electron density and pressure variability in the lower ionosphere to be studied, particularly near the 80 km altitude. This paper describes the theoretical background of the IPHA method, the measuring equipment used at Panská Ves, the method of evaluating records and checking of data, and the program package developed by us both for graphic and numerical processing, as well as our efforts to develop a homogeneous East European IPHA network. The IPHA method has been introduced succesfully at the Panská Ves Observatory. 相似文献
114.
E. V. Bunkše 《GeoJournal》1992,26(2):203-209
The dominant element in Latvian culture is nature rather than history. Latvians are as bound to place, to landscape, to particular geographies, as other peoples are bound to tribal legends and religions. Incorporation of this Baltic land into the Soviet Union in 1940 occasioned dramatic conflicts between these deeply-rooted orientations to the concrete facts of nature and the abstract formulations of Marxism-Leninism. The nature culture of Latvia, celebrated in daina, folk arts and crafts, is the bedrock on which the current independence movement has been built. Two major challenges are being addressed: the overt political one between Moscow center and the Baltic republics, and a deep intellectual conflict between the closed ideology of Marxism-Leninism and the open-ended nature and place-oriented cultures of the Baltic peoples. 相似文献
115.
Summary Four parameters defining the Earth's tri-axial ellipsoid (E) have been derived on the basis of the condition that the gravity potential on E be constant and equal to the actual geopotential value (W0) on the geoid. The geocentric gravitational constant, the angular velocity of the Earth's rotation, the actual 2nd degree geopotential Stokes parameters and W0 are taken to be the primary geodetic constants defining E and its (normal) gravity field. 相似文献
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