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In the design of pumped-storage plants it is necessary to solve two groups of problems. One is related to the determination of the hydraulic and static characteristics of a system of penstocks and reversible hydraulic machines operating under the turbine or pump regimes. In the same way as for ordinary hydroelectric plants, these characteristics may be obtained experimentally by using models operating under low heads. The hydraulic and power characteristics ate then recalculated by well-known methods for the actual conditions.The solution of the other group of problems, which is related to the determination and prediction of the dynamic characteristics of the flow in penstocks and through the reversible hydraulic machines is complicated by the need for taking into consideration unsteady processes whose unusual intensity is typical of installations with reversible hydraulic machines. :These problems can be solved if a method is found for determining the entire spectrum of disturbing frequencies and amplitudes of the pressure and flow fluctuations.At the present time investigations are being conducted in two directions. The first involves an attempt to predict theoretically the frequency spectrum of the disturbances. The second covers the problems relating to the formulation and carrying out of experimental investigations.The theoretical prediction of the disturbing frequencies is based upon the analysis and generalization of the results of many experimental investigations carried out for different types of hydraulic machines on models and prototypes. The basic spectrum of the disturbing frequencies is in this case functionallyrelated to the rotational rate of the units and the velocity of the flow through their internal elements and around the runner blades.The prediction of the amplitude values of the basic spectrum of the disturbing frequencies and of the distribution function is less reliable and depends upon the conditions under which the experiments are conducted. The most reliable results are those obtained at experimental installations with heads close to the actual ones, which, however, cannot be always reproduced in laboratories. These shortcomings considerably reduce the value of theoretfcal predictions, which are, however, undoubtedly useful for preliminary calculations during early design stages of the probability of the development of resonance phenomena in the powerhouse structure, the constructional elements of the units, and the penstocks. These preliminary calculations are frequently prepared before the special experimental investigations are carried out.The best method for solution of the above problem is the carrying out of experiments on models, although in this case the full reproduction of the dynamic and mechanical characteristics of the reversible hydraulic machines and of the penstocks involves great difficulties. These difficulties result mainly from the fact that it is necessary to reproduce the entire spectrum of the disturbing frequencies as well as the forms of their development and d...

We present and describe an automated method for analysis of magnetic data and for detection of geomagnetic disturbances based on wavelet transformation. The parameters of the computational algorithms allow us to estimate the characteristics of non-uniformly scaled peculiar properties in the variations of geomagnetic field that arise during increasing geomagnetic activity. The analysis of geomagnetic data before and during magnetic storms was carried out on the basis of the method according to ground station network. Periods of increasing geomagnetic activity, which precede and accompany magnetic storms, are highlighted. The dynamic of geomagnetic field variation in the auroral zone is considered in detail.