V.N. Lantsov - Dr.Sc.(Eng.), Professor, Vladimir State University named after A.&N. Stoletovs. E-mail: lant-sov@vlsu.ru A.A. Dolinina - Post-graduate student, Vladimir State University named after A.&N. Stoletovs. E-mail: Nas-tya.doly@gmail.com A.V. Pankratov - Post-graduate student, Vladimir State University named after A.&N. Stoletovs. E-mail: Aleksey112358@gmail.com