Study On The Liaoning Coastal Marine Disaster Simulation System

The development and utilization of the oceans has been further expanded with the advancement of science and technology. The21st century is the century of the oceans, the development and utilization of marine resources attracted every nation’s attention. At the Eighteenth National People’s Congress of the Communist Party of China, the establishment of marine power policy is clearly stated. In recent years, the increasingly frequent human activities at sea, more and more occurrence of marine disasters, the trend of the economic losses caused by marine disasters increased, which not only threatens the sea and coast, but also people’s lives and property safety. Therefore, the study and simulation of Liaoning coastal marine disaster has far-reaching significance.Based on the study and analysis of domestic and international development of WebGIS system and marine disaster, and we got little the study of combining WebGIS combined with marine disasters. This paper puts forward the concept of integration of WebGIS and marine disasters, and the technical route of the study. Compared existing technology of WebGIS system, this paper proposed framework of WebGIS based on the JavaScript API, that is Liaoning coastal marine geographic information system, which has friendly and beautiful interface, and easy to operate and interact, and conducted thorough study on the key technologies of the system.This paper describes the ArcGIS Server platform, the API technology, and the WebGIS, and explais the architecture WebGIS model and REST style, and selects B/S architecture model as the project of the thesis. Then, the thesis starts to study from the construction of marine geographic information map based WebGIS platform as the main line, the paper firstly studys the geographic data processing method, and introduces the details of the map construction and process of ArcMap map-building secondly, and last introduces the release services of ArcGIS Server Manager and the access services. This paper makes detailed design for WebGIS system of Liaoning coastal, and firstly describes the design goals and principles, then discusses the architecture design, finally introduces the functional design and interface design. Besides, the paper discourses the content and implementation of the system, which mainly included four modules-marine geographic information display, hydrometeorological query, historical disasters query and disaster simulation and prediction.This paper analyzes the dynamic map and cached map service, and compared the advantages and disadvantages of the two. Cached map service generates many pictures in advance, occupying hard disk space. However, it can reduce the computation load of the server to speed up the response speed of accessing a map. Cached map service can be used as further study of this subject. Dynamic map services can be step less zoom. Then object pooling expounded, and the pooling service can save the time of creating and destroying instances, occupying the server hardware resources less so that optimize overall system performance. And then this paper explains the technology from the client and server implementations:client development environment to build, the map service call, server-side operating environment, JDK and Tomcat environment configuration and release services of ArcGIS Server. Finally, other keys supporting technologies are introduced, explaining Java and JSON technologies in the form of examples in this topic.Finally, this paper introduces the application of the system, elaborating marine disaster type and cause characteristics of Liaoning coast and mainly explaining storm surges, oil spill, sea ice, waves and red tide disaster information selected in the system and counting serious disaster events of recent decades. For search and rescue module, using the actual case of search and rescue to show the function of the system, numerical simulation of search and rescue uses FVCOM model to calculate flow field in the accident area, building hydrodynamic model and entering the appropriate information from the client interface for operation and the calculation of the model is on the server side. There will be corresponding tips after completion of the calculation, and last the results can be displayed in the form of visualization on the client interface.