The Application Of Open Source WebGIS Technology In The Research Of Urban Disaster

Social development is facing a severe test, the vulnerability of population and environment is increasing constantly. The city is a concentration space of human activity and main carrier of regional economic, political, culture and so on. In recent years, urban disasters had a lot of types, the damage was increasing constantly and had become a focus of attention around the world. In 1999, the international global environmental change and human security research program (GECHS) had been established, the program attention to the research about natural disasters and vulnerability of urban. Because of the large number of aggregation of population, wealth and so on, the modern cities change the original natural conditions and social environment greatly. All human activities are growing dependence on the various functions of the city, but the recovery and security of the city is getting worse. Along with economic development and the process of urban modernization become fast, use means of advanced technology such as GIS to improve the capacity of disaster prevention and resilience of the city has become an urgent task of public safety of the city.WebGIS is a computer information system which could storage, process, display, analyze and apply geographic information in the environment of Internet or Intranet. It uses the computing model of Browser/Server and publishes electronic map with Internet, then it will achieve the functions of GIS. In this technology, there are many open source software (most of them are free) could be used to formation a structure which is cost-effective.This article is based on summarize and sum up the technology of open source WebGIS and its applications which are existing home and abroad right now. Combine the theoretical knowledge related to urban disaster, establish urban disaster database, develop spatial analysis toolkit, and construct urban disaster information system which base on open source WebGIS. All these will raise design standards of disaster database and spatial analysis toolkit, enrich construction method of urban disaster information system, provides credible analysis tool, system platform and technical support for the study of urban disaster. At the same time, provide a strong reference for other applications of open source WebGIS. The main conclusions are:(1) The open source software is low-cost, and not worse than most commercial software on efficiency. It is a good choice for developing WebGIS.(2)Finish the construction of shanghai urban disaster database based on the object-relational database PostgreSQL and spatial database engine PostGIS.(3)Develop the spatial analysis toolkit to achieve functions of query statistics, space calculation, thematic mapping, the results of the output and so on. Manage the various tools by categories, ensure their independence and also they could use each other.(4)Develop shanghai urban disaster information system based on open source WebGIS by using Apache, MapServer, PostgreSQL and PHP.