A.B. Nikitin – Ph.D.(Eng.), Associate Professor, Higher School of Applied Physics and Space Technologies, Peter The Great St. Petersburg Polytechnic University
E-mail: nikitin@mail.spbstu.ru
E.I. Khabitueva – Post-graduate Student, Higher School of Applied Physics and Space Technologies, Peter The Great St. Petersburg Polytechnic University
E-mail: basilliounderground@mail.ru