lower region and societal attributes (Social World) in the upper region. Acting as the combining agent for the two attributes, information is represented as having a role in every phase of disasters. Six zones, A through F, are defined in relation to periodic phases. Especially, topics important in understanding the socio-cultural setting and appropriate disaster-control philosophies are presented in zone G. A comprehensive and strategic approach to disaster-related topics is shown in zone H, whereby the lessons learned from the latest earthquake may be utilized. The holistic approach to disaster-control measures is the focus, in lieu of taking up each of the attributes individually. Each of zones is detailed below, sequenced in the order of relevance.
1) Zone A: We call this zone as Physical (Structural) Mitigation and Mitigation by Design and Planning. Earthquake reinforcement of existing structures is extremely important. Design standard with long return period of occurrence and including redundancy is also essential. Non-structural components such as urban grand design for safe/security society and urban planning for arrangement of new infrastructures and renewal ones.
2) Zone B: This zone is Recovery phase. Quick recovery of lifeline systems is very important. Damage assessment (certification for earthquake-resistant buildings) is urgent due to following aftershocks. Secondary disasters such as fire and tsunamis are also essential.
3) Zone E: This zone is named as Preparedness and Tactics. In order to smoothly and systematically perform the post-disaster measures, pre-disaster preparedness becomes extremely important. It include the reconstruction planning of urban areas because we have not enough time to design amenity-oriented and ecologically sustainable urban areas after disaster occurrence. Coordination of activities by fire-rescue teams, riot police and self-defense army (military) and distribution of volunteers are needed.
4) Zone F: This zone is Response and Strategy. Search and rescue is the most important. In the Great Hanshin-Awaji Earthquake Disaster, the number of the rescued people from collapsed houses was about 18,000 and more than 80% of them were picked out by neighbors. This certifies that individual efforts as well as public ones are the key of redaction of human damage. Logistics are also essential to supply anything the victims want and to require resolution of disposal of disaster debris.
5) Zone C: This zone is Abundancy. Acting as a unifying agent between societal and physical attributes, information systems must ensure the harmonious development of the overall response operation as it evolves over time. As a core device for this systems, Geographic Information Systems (GIS) should be promoted. Educational software for training and knowing disaster plays important roles in disaster preparedness.
6) Zone D: This zone is Communication. The role of information in the immediate aftermath of disasters is extremely important. Information on seismic activity and information on damage must be conveyed to the social world in real-time or at least within a short period.
In catastrophic disaster, Zone G as socio-cultural and philosophical background and Zone H as strategic topics are also important.
3. DISASTER MANAGEMENT FOR DAMAGE CONTROL
3.1 Disaster management
Traditionally, view points of urban engineering and technology focus on how to solve individual problems so that mind of urban engineers is not always enough microscopically well-balanced with our society. At first, they usually think how to construct urban functions. On the contrary, urban residents think that what is the most important thing to support their urban life? Under this requirement design and planning assessment is more essential than construction assessment. In Japan, unfortunately, such necessity of environmental assessment systems has not been recognized as a key of role to realize sustainable society. It takes more than 30 years to regulate the public nuisance such as industrial water pollution and air pollution. Recently, many Japanese companies have shift domestic manufacturing facilities to overseas especially in south Asian countries in which the pollution code of regulation is relatively moderate, even now. Occurrence of natural disasters is one of typical environmental problems. In order to reduce human and property damage due to natural disaster, disaster management systems should be established.
In Japan, no level of government has been accustomed to providing disaster management. Traditionally, importance has been put on risk management before disasters, but crisis management after disaster is equally important. For examples, the logistics of providing materials, workers and communications just after disaster is extremely important. Reconstruction planning has to be prepared before occurrence of disasters, because good planning takes a very long time and because accurate damage estimation before disaster is very important.
To have a good urban and regional environment, social mitigation is very important, social mitigation being the recovery of the urban environment lost due to rapid industrialization during the 1970s and 1980s in Japan. Previously public works had been kept in balance with such urban functions as economics and our life style, but during the 1990s the total urban system has not always been well balanced with urban life. The engineering and technical aspects of disaster measures are often discussed without the holistic and societal significance of the disaster-related subjects .Without clear understanding as to how to keep our society safe and comfortable, it will be impossible to realize good urban environment.
