Abstract: In order to improve the government's ability to manage social risk from major decision-making, a social risk situation discrimination model was built based on the dissipative structure theory. First, the entropy production accumulation and entropy flow accumulation in social system were used to construct a social risk situation discrimination function. The discriminant rule of the function was given according to Brusselator and its transferred meaning. Then, to adapt the nonlinear interaction among social risk factors, fuzzy measure and Choquet integral were used to calculate the entropy production and entropy flow in the social system at the different time nodes. At the same time, a method was worked out to calculate the accumulation of entropy production and the accumulation of entropy flow in the social system. Finally, the model was used to discriminant social risk situation caused by a PX project in a certain city. The results show that both increasing the accumulation of entropy flow and reducing the accumulation of entropy production can decrease the social risk, transforming a dangerous situation to a security situation.

Key words: social risk, dissipative structure, major decision-making, fuzzy measure, Choquet integral