The paper presents the results of complex analy sis of amplitude, velocity and time parameters for currents and voltages at arcing ground fault in power cable. The analysis is based on random samples obtained from real oscillograms. These oscillograms are recorded during ex perimental investigations in the 6 kV network. Hypotheses of distribution laws, outliers detection and correlational relationship are tested. Regression statistics is obtained for the following main parameters of arcing ground fault in cable insulation: duration of single breakdowns, duration of no-current condition, overvoltage level, rate of high-frequency arc current change before quenching, voltage recovery rate for a faulted phase under no-current condition, neutral-to-ground voltage amplitude after breakdown, breakdown voltage for a faulted phase. Ob tained statistical characteristics for arcing breakdown parameters and stochastic relationships between them can be used for further development of mathematical models of arcing in power cable insulation and for checking of relay protection efficiency using physical models.

Nonreciprocity, i.e. inequivalence in amplitudes and frequencies of spin waves propagating in opposite directions, is a key property underlying functionality in prospective magnonic devices. Here we demonstrate experimentally and theoretically...

In the context of regional gas infrastructure development this paper considers the issue of energy security of the countries of East Baltic, which depend heavily on a single energy supplier — Russia. In recent years, the countries of the region have announced several LNG terminal construction projects. The European Union will provide political and financial support to only one of these projects. The paper explores the role of gas and energy in the economy of the Eastern Baltic countries. The author concludes that the countries mostly dependent on Russian gas are Lithuania and Latvia. The announced LNG terminal projects are being reviewed in detail. Their necessity is estimated from the perspective of the current and future demand for natural gas, including the terms and conditions of contracts concluded with OAO Gazprom. Different scenarios and prospects for individual LNG terminal projects and associated pipeline infrastructure are evaluated. It is shown that the inability of countries to find a political compromise on this issue and the terms of existing contracts for Russian gas, as well as low domestic demand for gas hamper the implementation of a regional LNG terminal project even in the long term

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