Research On Cloud Model For Flood Inundation Analysis Based On Regular Grid DEM

The analysis of flood submergence is an important part of flood control and flood fighting work,and is a research hotspot of current GIS technology in the field of water conservancy application.Most of the early flood submergence analysis is based on hydrodynamic model,but the hydrodynamic model has strong pertinence,complex construction and many required parameters,which cannot be widely promoted.With the in-depth study of flood submergence analysis,many scholars found that flood submergence mainly depends on flood characteristics and topographic factors,and DEM can better reflect the surface fluctuation.However,DEM data also has some drawbacks that cannot be ignored,such as complex data structure and large amount of data.In the flood submergence analysis of large-scale research areas,due to the limitation of computer performance,its computational efficiency is low.For this reason,this paper studies the cloud model of flood submergence analysis based on regular grid DEM.The main research contents and results are as follows:1.Based on the analysis of the distributed storage system and the distributed computing framework of Hadoop cloud platform,combined with the data characteristics of rule grid DEM,the technical scheme of data processing of rule grid DEM under cloud platform is given.2.Designing storage scheme of DEM data based on cloud platform,including index construction and data parsing.The arithmetic design of submerged area segmentation and extraction of DEM data in regular grid under cloud platform is carried out,and the arithmetic design of cloud model for flood submergence analysis is completed.3.According to the storage and parsing mode of DEM data in the cloud platform,software development is carried out in combination with the corresponding development language to realize the design of common class and key pair of flood inundation analysis cloud model,and to map DEM data and model in the regular grid.According to the data characteristics of regular grid DEM,the input and output formats of the model are constructed,and the flood submergence analysis cloud model is finally realized.4.By extracting the submerged areas of Qinglan Lake,Junshan Lake,Chenjia Lake and Poyang Lake in Jiangxi Province under different water levels,it is verified that the model can meet the application needs of different watersheds in large-scale submerged area extraction,and can provide reference for flood control and flood control work quickly.