N.I. Chervyakov - Dr.Sc. (Eng.), Professor, Head of the Department of Applied Mathematics and Mathematical Modeling, North-Caucasus Federal University, Stavropol, Russia. E-mail: k-fmf-primath@stavsu.ru
M.A. Deryabin - Post-graduate Student, Junior Research Scientist, Department of Applied Mathematics and Mathematical Modeling, North-Caucasus Federal University, Stavropol, Russia. E-mail: maxim.deryabin@gmail.com
I.N. Lavrinenko - Ph.D. (Phys.-Math.), Associate Professor, Department of High Algebra and Geometry, North-Caucasus Federal University, Stavropol, Russia. E-mail: k-fmf-primath@stavsu.ru