TY JOUR TI THEORETICAL BASES OF MODELLING OF SAFETY OF SOCIAL AND ECONOMIC SYSTEMS KW social and economic systems KW safety KW modelling KW descriptive model KW normative model KW formalization KW survivability KW threatening JO NATURAL AND MAN-MADE RISKS (PHYSICO-MATHEMATICAL AND APPLIED ASPECTS) AU Matveev, A.V. AU Maksimov, A.V. PY 2014 IS 2014 PB Saint-Petersburg University of State Fire Service of Emercom of Russia