This article describes an approach of mathematical processing of signals (seismograms) from five blasthole charges from experimental blasting, each 3 m deep, with equal explosive weight (1 kg), and equidistant (3 m) from one other. The seismic explosive waves were measured at a 13 to 25 m distance. This article provides spectral analysis, wavelet analysis, and fractal analysis results. It defines the dependence of dominant frequency and amplitude on the distance to the blast center. According to the experimental data, the dominant frequency is calculated as y = 1.0262x0.2622 and the amplitude dependency as y = 18.139x−2.276. Furthermore, the analysis shows that 80% of the entire signal is concentrated in half the area of frequency range, i.e., the low frequency zone is of the most interest. This research defines the dependence of distance on the energy value of signal wavelet analysis. It is demonstrated that, according to the experimental data, the 12th frequency range is closely correlated with the distance values. This article gives the definitions of entropy, correlation dimension, and predictability time. This experiment shows that entropy and correlation dimension decrease but predictability time increases when the distance to the blast center increases. This article also describes the method for determining optimal drilling and blasting parameters, and concludes with the possibility of applying the analytical results to predicting and enhancing drilling and blast-ing operations.

This paper studies the effects of pipeline inner surface materials on hydrotransport energy parameters in the transportation of tailings slurry. It has been established that pipelines with inner surfaces made of polymeric materials ensure higher transportation energy efficiency due to lower specific pressure losses. The respective laboratory tests were carried out in two stages. At the first stage, pressure losses in the transportation of pure water and the initial roughness of the pipe samples studied were experimentally established. At the second stage, changes in sample roughness were studied in the hydrotransport of tailings slurry. The samples were represented by pipes made of high-density polyethylene with an inner layer of thermoplastic vulcanizate; single-layer pressure pipes manufactured in compliance with GOST 18599; and previously used longitudinally electric-welded steel pipes under GOST 10704-91. The influence of the hydraulic friction coefficient on the specific pressure loss and energy intensity of the hydrotransport process has been analyzed. Equivalent roughness values have been established for pipelines made of polymer materials and steel. The relationship between the roughness height parameters of Ra, Rq, Rz and the equivalent even-grained roughness has been established; their changes during tailings slurry hydrotransport ha

Месторождения полезных ископаемых арктического шельфа территориально рассредоточены, удалены от централизованных источников электрической энергии и требуют для разработки автономные источники электроэнергии, не зависящие от поставок топлива, такие как ветрогенераторы или солнечные генераторы. В свою очередь, для повышения эффективности использования установок генерации электроэнергии на возобновляемых источниках необходимо применять современные преобразователи электроэнергии для достижения максимального КПД. С целью обеспечения непрерывной работы генерирующих установок совместно с централизованной сетью необходимо обеспечить полную и мгновенную синхронизацию. Исследования проводились на основе статистических данных по генерации электроэнергии за счет ветряных турбин, а также метода контурных токов и узловых потенциалов для схем DC-DC и DC-AC-преобразователей. Для подтверждения результатов исследования проведено математическое и компьютерное имитационное моделирование бестрансформаторного DC-DC-преобразователя и разработаны системы управления для обеспечения синхронизации автономной энергосистемы на основе возобновляемых источников энергии с единой энергетической системой. Результаты моделирования показали эффективное применение DC-DC-преобразователей и DC-AC-преобразователей для обеспечения заданного уровня напряжения и синхронизации по фазе ветрогенераторной установки автономной системы электроснабжения с единой энергетической системой.