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131.
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Accurate measurement of the antenna voltage patterns of large-aperture synthesis radiometers is critical in order to achieve good radiometric accuracy, and a very time consuming and expensive task. Measurement requirements and a tradeoff study relating radiometric accuracy degradation and number of elements to be measured are presented.  相似文献   
133.
The specific features of formulation and implementation of balance-hydrodynamic simulation during different-scale studies of natural resources of groundwater. Are an example of detailed estimate of the resources and balance of groundwater in the Vologda River basin is given. It is noted that the use of balance-hydrodynamic models, in addition to an increase in the general reliability of estimates, allows the calculation of normal annual characteristics of groundwater resources with different occurrence (exceedance probability), which is impracticable when hydrodynamic methods in other formulations are used.  相似文献   
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Non-linear - dynamo waves existing in an incompressible medium with the turbulence dissipative coefficients depending on temperature are studied in this paper. We investigate of - solar non-linear dynamo waves when only the first harmonics of magnetic induction components are included. If we ignore the second harmonics in the non-linear equation, the turbulent magnetic diffusion coefficient increases together with the temperature, the coefficient of turbulent viscosity decreases, and for an interval of time the value of dynamo number is greater than 1. In these conditions a stationary solution of the non-linear equation for the dynamo waves amplitude exists; meaning that the magnetic field is sufficiently excited. The amplitude of the dynamo waves oscillates and becomes stationary. Using these results we can explain the existence of Maunders minimum.  相似文献   
138.
Results of the study of contents and accumulation rates of Fe, Mn, and a number of trace elements in Upper Quaternary sediments of the Deryugin Basin are presented. Maps of the average contents and accumulation rates of excess Fe, Mn, Zn, Ba, Ni, Pb, Cu, and Mo in sediments of the first oxygen isotope stage (OIS) have been plotted. Anomalous contents and accumulation rates are confined to peripheral zones of the Deryugin sedimentary basin and large fracture zones. Different mechanisms of the influence of fluid-dynamic processes on the rate of hydrogenic and biogenic accumulation of ore elements are assumed.Translated from Litologiya i Poleznye Iskopaemye, No. 2, 2005, pp. 115–132.Original Russian Text Copyright © 2005 by Astakhov, Gorbarenko, Bakhareva, Gretskaya, Sattarova.  相似文献   
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Summary The paper describes some characteristics of the precipitation patterns in the plain of Friuli-Venezia Giulia. Even if small, this Region shows a complex rainfall pattern so that, by previous studies, it was divided into four distinct areas with peculiar pluviometric regimes, namely the Coastal Area, the Plain and Hills Area, the Prealpine Area and the Inner Alpine Area. Nowadays a new data set, collected by the ERSA/CSA automatic stations, allows to propose a new sub-classification of the Coastal Area and Plain and Hills Area, under the point of view of the hourly rate of precipitation. This new sub-classification is composed by five zones: the Coast, the Carso, the Low Plain, the Middle Plain and the Piedmont. Each one of these zones presents a peculiar seasonal behaviour of the hourly rain-rate. Received May 31, 1999 Revised September 27, 1999  相似文献   
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