中文摘要：

全球离散格网为全球尺度的空间数据组织与管理提供了基础环境,而全球离散格网的编码体系,则可屏蔽不同坐标参考框架下的坐标转换,减少空间分析的复杂度,有利于数据的多尺度表达和统一建模。相对于其他类型的全球离散格网,基于正二十面体所构建的球面菱形离散格网具有更均匀的几何性质,有利于球面空间数据的集成与表达。但基于正二十面体的球面菱形离散格网的初始菱形边线并不贴合经纬线,这导致相对于基于正八面体的球面菱形离散格网,其格网结构更为复杂。这对构建正二十面体球面菱形离散格网的层次编码模型和建立其与地理坐标间的映射关系转换带来了新的挑战。针对这一问题,本文基于Hilbert曲线构建了正二十面体球面菱形离散格网编码模型,并在此基础上设计了格网编码与地理坐标的相互转换方法。研究表明,利用球面菱形离散格网与平面规则格网的相似性,基于Hilbert曲线构建的正二十面体球面菱形离散格网编码模型能够隐式表达空间尺度与位置信息,且在地理坐标与格网编码转换方面兼具效率与精度,可以支持全球海量空间数据建模、集成管理以及各类空间分析。

英文摘要：

Discrete Global Grid（DGG）provides a fundamental environment for global-scale spatial data＇s organization and management.DGG＇s encoding scheme,which blocks coordinate transformation between different coordination reference frames and reduces the complexity of spatial analysis,contributes a lot to the multi-scale expression and unified modeling of spatial data.Compared with other kinds of DGGs,Diamond Discrete Global Grid（DDGG）based on icosahedron is beneficial to the spherical spatial data＇s integration and expression for much better geometric properties.However,its structure seems more complicated than DDGG on octahedron due to its initial diamond＇s edges cannot fit meridian and parallel.New challenges are posed when it comes to the construction of hierarchical encoding system and mapping relationship with geographic coordinates.On this issue,this paper presents a DDGG＇s coding system based on the Hilbert curve and designs conversion methods between codes and geographical coordinates.The study results indicate that this encoding system based on the Hilbert curve can express space scale and location information implicitly with the similarity between DDG and planar grid put into practice,and balances efficiency and accuracy of conversion between codes and geographical coordinates in order to support global massive spatial data＇s modeling,integrated management and all kinds of spatial analysis.