A.Yu. Glazova - Post-graduate Student, Professor assistant, Department of Biotechnical Systems, Saint-Petersburg Electrotechnical University «LETI» n.a. V.I. Ulyanov (Lenin). E-mail: anna-glazova777@yandex.ru
A.A. Makarenkova - Ph.D. (Phys.-Math.), Senior Research Scientist, Department of Hydrodynamic Acoustic, Institute of Hydromechanics, The National Academy of Sciences of Ukraine (Kiev, Ukraine). E-mail: maa@mail.ru