The polyhedral discrete global grid system(DGGS)is a multi-resolution discrete earth reference model supporting the fusion and processing of multi-source geospatial information.The orientation of the polyhedron relati...The polyhedral discrete global grid system(DGGS)is a multi-resolution discrete earth reference model supporting the fusion and processing of multi-source geospatial information.The orientation of the polyhedron relative to the earth is one of its key design choices,used when constructing the grid system,as the efficiency of indexing will decrease if local areas of interest extend over multiple faces of the spherical polyhedron.To date,most research has focused on global-scale applications while almost no rigorous mathematical models have been established for determining orientation parameters.In this paper,we propose a method for determining the optimal polyhedral orientation of DGGSs for areas of interest on a regional scale.The proposed method avoids splitting local or regional target areas across multiple polyhedral faces.At the same time,it effectively handles geospatial data at a global scale because of the inherent characteristics of DGGSs.Results show that the orientation determined by this method successfully guarantees that target areas are located at the center of a single polyhedral face.The orientation process determined by this novel method reduces distortions and is more adaptable to different geographical areas,scales,and base polyhedrons than those employed by existing procedures.展开更多
Discrete Global Grid System(DGGS)is a new multi-resolution geospatial data modeling and processing scheme for the digital earth.The icosahedron is commonly regarded as an ideal polyhedron for constructing DGGSs with s...Discrete Global Grid System(DGGS)is a new multi-resolution geospatial data modeling and processing scheme for the digital earth.The icosahedron is commonly regarded as an ideal polyhedron for constructing DGGSs with small distortions;however,the shape of its face is triangular,making it difficult to incorporate the matrix structure used for geospatial data storage and parallel computing.To overcome this limitation,this study utilizes the rhombic triacontahedron(RT)as the basic polyhedron to construct DGGSs.An equal-area projection between the surface of RT and the sphere is developed and used to design a grid-generation algorithm for the aperture 4 hexagonal DGGS based on RT.Compared with the equal-area DGGS based on the icosahedron,the proposed scheme results in smaller angular projection distortions,with the mean and standard deviation decreasing by 41.6%and 30.9%,respectively.The grid cells of the RT DGGS also achieve more optimized geometric characteristics in shape compactness,length deviation,and angle deviation than those in the icosahedron DGGS.Additionally,the cross-surface computation efficiency provides advantages in code conversion to latitude and longitude and proximity queries.Furthermore,the use of RT offers a new and better framework within the context of DGGS research and application.展开更多
基金funded by the National Key Research and Development Program of China[grant number 2018YFB0505301]the Natural Science Foundation of China[grant number 41671410].
文摘The polyhedral discrete global grid system(DGGS)is a multi-resolution discrete earth reference model supporting the fusion and processing of multi-source geospatial information.The orientation of the polyhedron relative to the earth is one of its key design choices,used when constructing the grid system,as the efficiency of indexing will decrease if local areas of interest extend over multiple faces of the spherical polyhedron.To date,most research has focused on global-scale applications while almost no rigorous mathematical models have been established for determining orientation parameters.In this paper,we propose a method for determining the optimal polyhedral orientation of DGGSs for areas of interest on a regional scale.The proposed method avoids splitting local or regional target areas across multiple polyhedral faces.At the same time,it effectively handles geospatial data at a global scale because of the inherent characteristics of DGGSs.Results show that the orientation determined by this method successfully guarantees that target areas are located at the center of a single polyhedral face.The orientation process determined by this novel method reduces distortions and is more adaptable to different geographical areas,scales,and base polyhedrons than those employed by existing procedures.
基金supported by the Special Science Fund for Innovation Ecosystem Construction of National Supercomputing Center in Zhengzhou[grant no 201400210100]the National Key Research and Development Program of China[grant no 2018YFB0505301].
文摘Discrete Global Grid System(DGGS)is a new multi-resolution geospatial data modeling and processing scheme for the digital earth.The icosahedron is commonly regarded as an ideal polyhedron for constructing DGGSs with small distortions;however,the shape of its face is triangular,making it difficult to incorporate the matrix structure used for geospatial data storage and parallel computing.To overcome this limitation,this study utilizes the rhombic triacontahedron(RT)as the basic polyhedron to construct DGGSs.An equal-area projection between the surface of RT and the sphere is developed and used to design a grid-generation algorithm for the aperture 4 hexagonal DGGS based on RT.Compared with the equal-area DGGS based on the icosahedron,the proposed scheme results in smaller angular projection distortions,with the mean and standard deviation decreasing by 41.6%and 30.9%,respectively.The grid cells of the RT DGGS also achieve more optimized geometric characteristics in shape compactness,length deviation,and angle deviation than those in the icosahedron DGGS.Additionally,the cross-surface computation efficiency provides advantages in code conversion to latitude and longitude and proximity queries.Furthermore,the use of RT offers a new and better framework within the context of DGGS research and application.
