TY JOUR TI TORUS, CYLINDER AND CONE RESEARCH BY MEANS OF COMPUTER MODELLING AS FREQUENTE CASES OF DUPIN CYCLIDE KW Dupin's cyclide KW surface design KW second-order curves KW computer graphics JO Scientific and analytical journal «Vestnik Saint-Petersburg university of State fire service of EMERCOM of Russia» AU Shiroukhov, A.V. AU Tyshchenko, I.V. AU Brykova, L.V. PY 2019 IS 2019 PB Saint-Petersburg University of State Fire Service of Emercom of Russia