Great East Japan Earthquake Emergency Evolution and Contingency Decision Based on System Engineering Approach

In recent years, unconventional emergencies that have generated widespread concern in the society have frequently occurred. In 2011, the Great East Japan Earthquake and the nuclear crisis as a result of this disaster have gained tremendous attention worldwide. The present paper used a system engineering approach, an extended event graph, to analyze this earthquake and its event evolution as well as associated contingency decisions. Some pertinent countermeasures are also presented for reference of similar emergency event evolution in the future.