K.K. Vasiliev - Dr. Sci. (Eng.), professor, Ulyanovsk State Technical University. E-mail: vkk@ulstu.ru
V.E. Dementiev - Ph.D. (Eng.), associate professor, Ulyanovsk State Technical University. E-mail: vitawed@mail.ru
N.A. Andriyanov - post-graduate student, Ulyanovsk State Technical University. E-mail: nikita-and-nov@mail.ru