D.V. Ivanov1, V.A. Ivanov2, N.V. Ryabova3, A.R. Laschevsky4

1–4 Volga State University of Technology (Yoshkar-Ola, Russia)

1 IvanovDV@volgatech.net, 2 IvanovVA@volgatech.net, 3 RyabovaNV@volgatech.net, 4 LashhevskijAR@volgatech.net