V.V. Kamenskiy1, S.V. Sokolov2

1 Rostov State University of Railway Engineering (Rostov-on-Don, Russia)

2 Moscow Technical University of Communications and Informatics (Moscow, Russia)

1 kam-vladislav@yandex.ru; 2 s.v.s.888@yandex.ru

S.Sh. Rekhviashvili1, D.S. Gaev2

1 Institute of Applied Mathematics and Automation, KBSC RAS (Nalchik, Russia)

2 Kabardino-Balkarian State University named after H.M. Berbekov (Nalchik, Russia)

1 rsergo@mail.ru; 2 dahir@mail.ru