A New Early Warning Evaluation Method and Decision Mechanism for Urban Significant Emergency in Uncertain Environment

This study presents a new early warning evaluating method and decision mechanism for urban emergency in which the risk factors are easily assessed by fuzzy numbers. By using the fuzzy preference relation matrix and the extended fuzzy AHP, the relative weight of each risk factor can be estimated. Then we evaluate the total fuzzy risk value by aggregating the severity of loss of risk factor and the relative weight of risk factor. According to the similarity between the fuzzy comprehensive risk value and the pre-established risk grade, the early warning grade of the urban significant emergency can be determined for urgent emergency decision-making.