With the country's unique position within the Ring of Fire, such natural hazards have become part and parcel of everyday life in Japan. Accordingly, the nation is considered a model for disaster preparedness: each resident is advised to carry fireproof evacuation bags with first aid, sanitation products as well as food and water. Meanwhile, buildings constructed after 1981 are required to have earthquake-resistant structures, meaning thicker beams, pillars and walls as well as shock-absorbers to reduce shaking in taller buildings. And yet, the 2011 Great East Japan Earthquake came as a huge shock--literally. On March 11, 2011, the Tohoku region along Japan's eastern coast was rocked by a magnitude 9.0 earthquake for six minutes; the strongest in the country's records so far.

In the Harry Potter films, Hogwarts headmaster Albus Dumbledore shows the young wizard memories that he keeps in glass vessels. The franchise portrays memories as things that possess a physical structure that can be moved around. Although they appear to look like wispy bits of fluff, they are given form and structure. Is this in anyway similar to real life? To answer these questions, I spoke to Lila Davachi, who runs the Memory Lab at New York University.

The frequency and intensity of natural disasters has significantly increased over the past decades and this trend is predicted to continue. Facing these possible and unexpected disasters, urban emergency management has become the especially important issue for the whole governments around the world. In this paper, we present a novel intelligent system for urban emergency management during the large-scale disasters. The proposed system stores and manages the global positioning system (GPS) records from mobile devices used by approximately 1.6 million people throughout Japan over one year. By mining and analyzing population movements after the Great East Japan Earthquake, our system can automatically learn a probabilistic model to better understand and simulate human mobility during the emergency situations. Based on the learning model, population mobility in various urban areas impacted by the earthquake throughout Japan can be automatically simulated or predicted. On the basis of such kind of system, it is easy for us to find some new features or population mobility patterns after the recent and unprecedented composite disasters, which are likely to provide valuable experience and play a vital role for future disaster management worldwide. Figure 1: What kinds of experiences or model can we learn from the unprecedented composite disaster of Japan in 2011?