I.V. Sivchek - Post-graduate Student, St. Petersburg State Polytechnical University. E-mail: cotgreat@gmail.com
V.A. Sorotsky - Dr. Sc. (Eng.), Head of Department, St. Petersburg State Polytechnical University. E-mail: sorotsky@mail.spbstu.ru

R.I. Zudov – Assistant, Peter The Great St. Petersburg Polytechnic University

V.A. Sorotsky – Dr.Sc.(Eng.), Professor, Associate Professor, Peter The Great St. Petersburg Polytechnic University