【作者】 王建平；

【导师】 任立良；

【作者基本信息】 河海大学 ， 水文学及水资源， 2005， 硕士

【摘要】 从数字高程模型(Digital Elevation Models)DEM直接提取河网及相关流域信息,是分布式水文模型开发与应用的基础。本文在分析目前主流河网提取算法之基础上,自行开发了一套DEM凹陷区域识别与处理、河网自动生成与流域划分软件,在此基础上与数字水文模型进行了耦合,并采用软件工程方法和面向对象的思想对整个系统进行设计。 首先详细介绍了数字高程模型的数据类型、模型转换方式、生产方式和目前得到这些数据的几种方法。根据目前DEM数据预处理的各种方法,进行了算法复杂度分析和比较,最后将用于土壤学的一种填洼方法用于DEM预处理,实现简单,且运算速度提高。基于D8(eight flow direction matrix)方法、Garbrecht编码开发出一套DEM凹陷区域识别与处理、河网自动生成、流域划分与拓扑关系生成软件,同时该软件可人为添加控制点(如水库、水文站),克服了一般数字水系提取工具只能按河网汇合点分子流域的缺点,更加适用于实际生产。在褒河流域,应用本软件在30秒空间分辨率的DEM数据上生成的河网与全国1/25万的数字河流对比验证,吻合较好。结果表明,所开发软件能够很好地自动生成流域水系,可为进一步开发分布式水文模型提供技术基础。 在数字水系生成系统的基础上,构建分别基于子流域的离散数字水文模型。对数字水文模拟系统可视化实现中的几个关键技术,编程实现中数字水系编码、子流域编码与水文模型所需信息之间融合以及选择的数据结构进行了探讨,使系统达到无缝高效的集成。该系统为水文模型比较、参数率定和模型空间状态变量的可视化提供了平台,同时也为数字水文模拟系统实用化进行了尝试。 基于系统的需求分析,进行系统分析建模,识别参与者和用例,构建系统用例图;然后对系统体系结构、数据库结构进行了设计。用面向对象的思想抽象出系统中的实体类以及界面类,并用OpenGL图形库和VC++开发出了可视化系统;最后,用褒河地区的资料对系统进行了实例应用,得到了较好的效果。更多还原

【Abstract】 Digital hydrological model is developed on the platform of digital basin derived from raster-based digital elevation data. The software system is developed which could automatically delineate watershed divides, generate the river network and subcatchments, and establish the topological river network structure. It can be coupled with the modified Xin’anjiang model by object-oriented method.The depressions which are frequently present in DEMs may represent the actual topography, but are often the result of errors. Creating a depression-free surface is commonly required prior to deriving flow direction, flow accumulation, flow network, and watershed boundary maps. After comparing the performance of the usual algorithms used to remove depressions from DEMs, a simple method is introduced which is originally applied in the study of soil erosion process. The algorithm is easy to understand and to implement, requiring only a few tens of code lines. It is much faster than usual algorithms. On the basis of the algorithm, D8 (eight flow direction matrix) method and Garbrecht’s coding system, a software is designed and developed to generate digital basin and to establish the topological river network structure. Moreover, control points, such as hydrological stations and reservoirs, are allowed to be added to the process of generating digital basin, so as to be easily coupled with hydrological model..Researches were made on several key techniques of visualizing hydrological system, viz. how to code digital drainage networks and digital basin and how to select the suitable data structure to match digital hydrological model. The system was developed by OpenGL graph library(Version 1.2) and Visual C++(Version 6.0). The system could provide the platform, on which it is easy to calibrate model parameters, visualize the spatial distributions and time series of hydrological elements, such as precipitation, evaporation, discharge, and state variable. Finally, a case study was implemented on the Baohe Catchment, the tributary of the Hanjiang River in Shanxi Province.更多还原