【作者】 朱广堂；

【导师】 王乘；

【作者基本信息】 华中科技大学 ， 水利水电工程， 2005， 博士

【摘要】 大型水利水电工程施工是一项复杂而又艰巨的工作,利用计算机进行辅助管理是人们一直来追求的目标。本文深入研究了计算机可视化的有关理论与方法,并结合实际工程需要,将GIS技术应用于水利水电工程施工。以信息的数字化、直观化、可视化为出发点,将复杂的工程施工过程以可视化的形式表达出来,为全面、准确、快速地分析掌握工程施工全过程提供有力地分析工具,实现工程施工信息的高效应用和科学管理。本文的研究将有助于推动水利水电工程施工的数字化、可视化、智能化方向发展,具有广阔的应用前景。本文的主要研究工作如下: 1)针对当前水利水电工程施工设计领域存在的计算机应用水平还有待于提高,设计建模过程复杂且不直观,设计效率不高等情况,研究了基于GIS的水利水电工程施工可视化设计理论与方法,实现了直观方便的设计建模和设计过程的交互控制,以及设计成果的直观形象表达,从而有助于提高工程施工的效率和质量。2)构建了基于GIS的水利水电工程施工的三维实时可视化仿真系统的整体框架。目前GIS与可视化仿真结合的方式主要包括:(1)融合式,这种集成方式尽管两者间数据传递方便高效,操作简便,但开发费用高,开发周期长; (2)扩展式,通过建立两者的扩展模块来实现彼此间数据相互交换和信息共享,此方式开发简便、费用低廉,而且由于两者的相对独立性及可扩展性,便于系统的维护及进一步开发。为了更加逼真形象地描述复杂的水利水电工程施工系统内部的时空逻辑关系,简化仿真建模过程以及直观获取与表达仿真信息,本文提出了两种模式混合使用的方法。3)针对系统中的三维地形实时可视化,提出了面向对象的、基于DEM的视点相关的实时连续LoD地形构网算法。基于GRID数据,以直角三角形为基本单元,利用交叉四叉树构建地形的多分辨率细节层次。在保持视觉效果基本不变的情况下,以虚拟地形的动态构网算法及绘制效率为出发点,在传统的SOAR网格算法基础之上,研究了四个与视点相关的判据法则来实时生成多分辨率地形网格:(1)屏幕空间误差; (2)不可见顶点剔除; (3)顶点方向性判断; (4)视角因子。4)针对本文研究的地形构网算法,提出了面向对象的三层体系地形可视化的实更多还原

【Abstract】 The construction of the huge hydroelectric engineering is a complex and hard work. Using computer to aid management is the objective which people have being pursuit for. With the technique of Geographic Information System applied in the hydroelectric engineering construction, the theory and the methodology of the computer visualization and its application are deeply studied in this thesis. Based on the digitalization, intuition and visualization of the information, the complex processes of the engineering construction are visually expressed, which provides an effective tool to roundly, truly and fleetly analyze and comprehend the whole engineering construction, and achieve the effective application and the scientific management of the engineering construction information. The study would be very helpful to promote the reformation of the hydropower engineering construction with the tendency to the digitalization, visualization and intelligence, and the perspective of its application would be very bright. Summarily, the main studies and achievements of this thesis are listed as following: Firstly, the theory and methodology of GIS-based construction management of the hydropower engineering is studied in this thesis in order to enhance the level of computer-aided management, simplify the complex design processes and improve the design efficiency. Based on the method, the design modeling and the interactive control could be realized conveniently and visually during the design processes, and the visual representation of design results could be obtained. To the end, the efficiency and quality of the engineering construction could be largely promoted. Secondly, the system framework of the GIS-based three-dimension real-time visualization simulation applied to hydropower engineering construction is designed in the thesis. At present, there are two main integrating ways on GIS and the visual simulation, which are:(1) Melting pot, which data transmission is convenient, effective and simple, but needs expensive expense and longer development cycle. (2) Expansion schema, which is realized to data exchange and information share by establishing expansion zones, and this schema is easily developed, and needs cheap expense, and conveniently maintained, further researched. To realistically and vividly describe the space-time logistic relations of the complex hydroelectric engineering construction, and simplify the simulation models and get the information directly, the mixed way of both is presented and applied in this thesis. Thirdly, in order to solve the visualization problem of the terrain, the rendering algorithm of real-time continuous level of detail of the terrain is presented based on the object-oriented, view-dependent and DEM. And the multi-resolution model of level of detail is constructed by use of crossed quad-tree structure, which is based on the GRID DEM and the right-angled triangle cell. Under the permission of visual effect, and real-time rendering efficiency of the algorithm of the virtual terrain considered, four criterion principles in relation to the view-dependent based on the traditional SOAR grid algorithm are studied, which include as follows: (1) Screen space error. (2) Elimination of the sightless vertex. (3) Judgement of the vertex direction. (4) Coefficient of the angle of view volume. Fourthly, in order to implement the rendering algorithm of the terrain, a system structure of the virtual terrain including three ties based on the object-oriented technique is presented in this thesis. The whole terrain simulation processes are divided as the preprocessing, the real-time processing and the post processing. During the preprocessing, the structure file *.ecsiinfo that will be provided for the real-time process is produced after analysis of the DEM; Constructing and rendering of the real-time grid are finished on the basis of the optimal algorithm and the four criterion principles during the real-time processing; The exporting of image, the movie recording of the 3-D visual rambling and the querying of the 3-D information are disposed in the post processing. As a result, the real-time 3D visual terrain system based on the techque of DEM and LoD has been developed. Fifthly, the extending technique of terrain visualization based on fractal theory is presented in this thesis. According to the excavating and filling of the terrain of the engineering construction, the rendering algorithm of the terrain that combines real terrain data and fractal theory is disposed, which can not only render the whole terrain shape with the real terrain data, but build the detail part of the terrain by fractal theory. The algorithm is superior to the other two algorithms, which overcomes the storage problem of the scale terrain data and assures more reality of the terrain. Sixthly, the framework of the visual simulation is designed to 3-D DAM filling based on GIS. The system make fully use of object-oriented modeling, MVC software mode, GIS component, spatial database, big file memory mapping, SOCKET communication technique etc, these techniques can not only simply modeling and describe the complex progresses of the DAM construction, but also analysis and compare different schemesvisually, thus it can provide scientific decision-making theory for the planning, the schedule controlling, and the management of the DAM construction. Based on the above theory, a 3-D simulation system of the DAM construction has been developed. At last, a detailed conclusion on the whole work and the research results on this paper is summarized, and the improved aspects and the proposals to the future are discussed.更多还原