选取广东省阳山县基本农田调整划定入库数据作为研究对象,借助ArcGIS软件对该地区面状要素数据层的图斑结构错误进行探讨研究,灵活利用Multipart to Signelpart工具及形状指数法进行GIS空间数据错误查找。文章系统地将GIS空间数据错误...选取广东省阳山县基本农田调整划定入库数据作为研究对象,借助ArcGIS软件对该地区面状要素数据层的图斑结构错误进行探讨研究,灵活利用Multipart to Signelpart工具及形状指数法进行GIS空间数据错误查找。文章系统地将GIS空间数据错误总结为三大错误类型并提出了一套系统的查找处理方法流程,提出了带"狭长线"不正规多边形和带"碎屑"不正规多边形等的形态定义,特别是对于隐蔽性极强的带"狭长线"不正规多边形和"狭长"多边形等错误利用形状指数法进行查找,结果表明,使用这种方法,比人工遍历查找可显著提高工作效率。展开更多
This article mainly aims at developing an integrated 2-D numerical simulation model on inundation, sediment transportation and the morphological variations of floodplains due to high sediment-laden inundation flows. D...This article mainly aims at developing an integrated 2-D numerical simulation model on inundation, sediment transportation and the morphological variations of floodplains due to high sediment-laden inundation flows. Due to the complexity of inner and outer boundaries and the arbitrary structures within the computational domain of floodplains, an unstructured Finite-Volume Method （FVM） based on an irregular polygon mesh was worked out so that the influences of complex boundaries can be integrated into the simulation. A case study was conducted in the Lower Yellow River Basin, in which a dike-break at the Huayuankou Hydrological Station was assumed to happen when a flood scale of 1982 was suffered in the region. The simulated spatial distribution of sediment deposition and erosion can be used to reasonably explain the natural phenomena of ＂suspended river＂ of the lower part of the Yellow River. It is concluded that the inundation process of water is similar to a variable-river-bed condition during the simulation because the sediment deposition and erosion are modified by new values at the end of each time step. The mass and momentum conservation were strictly followed during the simulation. Therefore, the prediction of floodplain evolutions by the integrated simulation model, proposed in this study, can be adequately and accurately given if the real condition of an floodplain can be obtained in detail.展开更多
文摘选取广东省阳山县基本农田调整划定入库数据作为研究对象,借助ArcGIS软件对该地区面状要素数据层的图斑结构错误进行探讨研究,灵活利用Multipart to Signelpart工具及形状指数法进行GIS空间数据错误查找。文章系统地将GIS空间数据错误总结为三大错误类型并提出了一套系统的查找处理方法流程,提出了带"狭长线"不正规多边形和带"碎屑"不正规多边形等的形态定义,特别是对于隐蔽性极强的带"狭长线"不正规多边形和"狭长"多边形等错误利用形状指数法进行查找,结果表明,使用这种方法,比人工遍历查找可显著提高工作效率。
文摘This article mainly aims at developing an integrated 2-D numerical simulation model on inundation, sediment transportation and the morphological variations of floodplains due to high sediment-laden inundation flows. Due to the complexity of inner and outer boundaries and the arbitrary structures within the computational domain of floodplains, an unstructured Finite-Volume Method （FVM） based on an irregular polygon mesh was worked out so that the influences of complex boundaries can be integrated into the simulation. A case study was conducted in the Lower Yellow River Basin, in which a dike-break at the Huayuankou Hydrological Station was assumed to happen when a flood scale of 1982 was suffered in the region. The simulated spatial distribution of sediment deposition and erosion can be used to reasonably explain the natural phenomena of ＂suspended river＂ of the lower part of the Yellow River. It is concluded that the inundation process of water is similar to a variable-river-bed condition during the simulation because the sediment deposition and erosion are modified by new values at the end of each time step. The mass and momentum conservation were strictly followed during the simulation. Therefore, the prediction of floodplain evolutions by the integrated simulation model, proposed in this study, can be adequately and accurately given if the real condition of an floodplain can be obtained in detail.
