V.R. Krasheninnikov - Dr. Sc. (Eng.), Professor, Head of Department «Applied Mathematics and Informatics», Ulyanovsk State Technical University E-mail: kvr@ulstu.ru Yu.E. Kuvayskova - Ph. D. (Eng.), Associate Professor, Department «Applied Mathematics and Informatics», Ulyanovsk State Technical University E-mail: u.kuvaiskova@mail.ru