Design And Implement Of3D Digital City Fire Protection Information System

In recent years, frequent urban conflagrations have seriously menaced public security and the social development, and in the meanwhile, with high paroxysm and massive destructiveness, conflagrations usually lead to tremendous losses of life and property of nationals. Therefore, it is of great significance to urban conflagrations rescue if they could be extinguished timely and scientifically. With the rapid development of3S technology and computer technology, Fire Protection Geographic Information System is becoming an auxiliary tool for collection, location and analysis of disaster information for fire protection department and the integration of3D visualization technology and fire protection information system is particularly becoming a hot spot. Based on the characteristics of urban fire protection, this dissertation concentrates on the system design, the research of core technology and the realization of main functions. According to the perspective of3D digital visualization of the city, fire fighting resource management and fire fighting emergency services, the3D Digital City Fire Protection Information System has been implemented based on the effective integration of virtual reality technology, GIS and fire protection resources. Based on the goal of the system, we have accomplished system design, core technology and the realization of main functions and the main research contents are as followed:(1) The system makes use of the C#programming language to utilize SQL Server2008database to manage and analyze data, based on NET Framework3.5and Skyline5.1.3. Being Client/Server oriented, this system implemented a3-tier separation of presentation layer, business layer and data access layer. Business layer consists of application layer and component layer. System functions are composed of three subsystems, which are map operation subsystem, fire resource management subsystem and fire emergency services subsystem. Map operation subsystem is made up of the basic operation of map, map measuring, scene marking and so on. Fire fighting resource management is comprised of query, update and maintenance of fire protection resources. Fire emergency services contain fire spreading, vehicle scheduling and inside building checking and so on.(2) The present paper focuses on the core technologies of3D digital city modeling, conflagration spreading analysis and the best path model. In the process of building city3D digital model,3D-models are optimized by LOD technology and loaded by stream, and do the same with the models’ texture mapping which will significantly improve the display efficiency of3D data and browsing experience the users.Based on the characteristics of urban fire spreading, spreading process is divided into the internal spreading of single building and the spreading of buildings around. Wind speed and direction, the flammability of building materials are fully considered, and fire spreading is simulated in the incident place. By the best path model, the writer carry on the synthesis appraisal of fuzzy factor, which would affect the network weight with the help of fuzzy theory. Consequently, the result synthesizes the influence of various factors, and avoids problems caused by traditional static weight algorithm such as consider one element and calculate poor reasons. Finally, the system makes use of Dijkstra algorithm to realize the choice of best path.(3) The present paper elaborates the details in the main functions of the realization of3D Digital City Fire Protection Information System, including basic map operation, maintenance and update of fire fighting resources, conflagration emergency services and so on. According to simulation testing, the system basically realizes the design goals and has a better feasibility on the fire protection emergency functions based on3D digital city. However, confined by the sophistication of fire protection information system and technology, there is a little defect in the integration of3D visualization and spatial analysis and in the design of the fire protection decision analysis model. Hence, the system needs to be continuously improved and optimized in the actual applications.