Research On The Key Technologies Of Integrated Digital Model In Changjiang River

The harmonious development between man and nature is the scientific concept of development in current. The new human-water harmonius idea of regulating watercourses implements this new concept of scientific development.With the sustainable development of social economy, demand on the sustainable use of the water resource can be represented in many regions in Changjiang River, however, Changjiang River still faces floods, droughts, water pollution, water environmental degradation, soil erosion and other outstanding issues, which have a bad impact on the health of the Changjiang River.At the same time, the contradictions between utilization of water resources and ecological environment protection have become outstanding. Scientific and technological means are needed to manage and protect Changjiang River.Therefore, it is very important to establish the integrated digital model system in Changjiang basin. The system realizes the quantitative monitoring, simulation, analyzing and forecasting of river basin from the rainfall, runoff to flood evolution, sediment transport, water quality, watershed ecology and environment, water resources development and utilization of the Changjiang River. It takes a positive role in the process of making a scientific decision in water resource assessment, development and utilization of soil and water conservation planning, economic development planning, environment and water policy planning.The paper presented the concept and basic framework of integrated digital model in Changjiang River, through a comprehensive and systematic analysis, which considering the requirement of river basin management. At the same time, it studied the issues of the key technology of "Model Parameter Extraction Based on Remote Sensing Technology" and interoperability platform. The paper applied the theory of integrated model framework on the selected typical area for a demonstration study and lays a solid foundation for comprehensive management and development of the Changjiang River basin decision making. Thesis research and innovation are in the following areas:It firstly proposed the concept of integrated digital model in Changjiang River basin and designed the system construction. The thesis researched and discussed the background of the integrated digital model, put forward the concept, analyzed the overall structure, and carried out the demand analysis, come up with the system framework clearly, provided a guiding ideology to the system construction.This paper researched the interoperability and interface technology of integrated digital model of Changjiang River. Introducing GIS interoperability, it went into the problem of interoperability property for this model system, gave the definition of the integrated digital model from the view of software technique. Then, it described two key techniques for the integrated digital model:Web Service and SOA. According to the characteristics of the integrated digital model, it put forwards some service chain models:transparent chain, translucent chain and opaque chain. According to the introduction of interoperability and combined the characteristics of this system, with the example of pollution diffusion model, the paper analyzed the interfaces of the model system.The paper studied on the methods of moisture monitoring based on the ASAR images. And it introduced the means of the parameter extraction from the remote sensing images in the basin, deals with soil moisture extraction from the ASAR images. According to the characteristics of ASAR satellite images, the paper chose some appropriate algorithms, with the support of the ground sampling point data, it analyzed the correlation between soil moisture and ASAR value of Zhanghe River irrigation district and created a remote sensing inversion model of soil moisture. Using this model, the soil moisture of Zhang River irrigation district is monitered.A demonstration application system of Changjang River integrated digital model is established. Based on the previous research, the thesis analyzed of the modeling environment and modeling methods. Then, the establishment of a demonstration system is done. In the demonstration system, hydrodynamic model and pollutant dispersion model are integrated in 3D scene, and seamless interfaces between hydrodynamic model and Pollutant dispersion model, models and 3D scene are developed. LOD (level of details) and multilevel texture techniques are used to quick browser mass 3D data in this system. And it validated the above modeling methods. The results of this experiment showed that the theory and methodology of integrated digital model is advanced and feasible.