A Class of Numerical Algorithm for Impact Degree Assessment of Emergency Systems.

A standard procedure for the evaluation of emergency impact is developed, concentrating on variation of the impact degree. A numerical method is presented in this paper. The concepts of impact depth and impact width are introduced to assess the impact degree, and both of which determine the evolution path of impact. Based on the variation pattern of impact depth, the evolution path could be divided into rising stage, plateau stage, and recession stage, and path of each stage could be expressed in terms of specified functions. The major goal of this procedure is to measure the emergency impact and make predictions for the consequences. In the case study, we applied this procedure to the analysis of the impact caused by 3.11 earthquake in Japan and demonstrated the algorithm's effectiveness and feasibility. Although this methodology shows improvement in quantitative analysis of the emergency impact, the accuracy of the impact path and the derivative effect of secondary derivative events are issues that yet to be further studied.