Flood Spatiotemporal Process Simulation And Visualization For Diversified Terminals Based On WebGIS

Flooding is one of the most destructive natural disasters, which occurs frequently in China. The simulation and visual analysis of flood spatiotemporal process is of great importance for disaster prevention and reduction. Domestic and international scholars have done a large amount of research on the flood simulate mathematical model and visualization method. In addition, some flood disaster information system has been developed with GIS technology. However, most systems are professional desktop applications, while a small number of Web applications mainly focus on the display of flood disaster information via the two-dimensional map. Thus, there is a lack of the cross-platform web application, which supports the simulation and visual analysis of flood spatiotemporal process on diversified terminals. This paper takes dam-break flooding as an example to research the simulation and visualization of flooding spatiotemporal process under network environment for diversified terminals by technologies of Web GIS, three-dimensional visualization and network data transmission. The main work in this paper consists of the following aspects.(1) Architecture design for the flood spatiotemporal process simulation and analysis system. The B/S network architecture was designed taking care of the load balancing between browser and server. On the server side, the GPU-CA dam-break flood model was integrated to improve calculative efficiency. On the client, WebGL technology was applied to construct virtual terrain environment and visualize the flood routing dynamically. According to the analysis of network communication and data transmission strategy, two typical flood routing presentation and analysis schemes were designed for the public and experts.(2) UI design and data organization for diversified terminals. Contrast has been made on the features of diversified terminals including hardware performance, operating system, screen size, human-computer interaction and network environment. Different user interfaces and interaction modes were designed for desktop and mobile web application respectively. Furthermore, the calculation data of dam-break flood simulation were organized and optimized to be better adapted to data transmission under network environment and rendering on browser side.(3) Prototype system development and case experience analysis. A dam-break flood spatiotemporal process simulation and analysis system was developed. Based on the example of Xiaojiaqiao Barrier Lake, an experiment on dam-break flood routing simulation and visualization analysis was carried out by diversified terminals. The experimental results showed that the schemes designed in this paper, can provide effective support for users to simulate the flood routing and make visualization analysis in the virtual terrain environment by diversified terminals (desktop, laptop, smartphone and tablet) under network environment.