检索结果-南通市图书馆

International Journal of Digital Earth 2022年第1期15卷 975-1000页

作者： Long Zhao Guoqing Li Xiaochuang Yao Yue Ma Qianqian Cao Aerospace Information Research Institute Chinese Academy of SciencesBeijingPeople’s Republic of China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijingPeople’s Republic of China College of Land Science and Technology China Agricultural UniversityBeijingPeople’s Republic of China

Although research on the discrete global grid systems (DGGSs) has become an essential issue in the era of big earth data,there is still a gap between the efficiency of current encoding and operation schemes for hexagonal DGGSs and the needs of practical applications. This paper proposes a novel and efficient encoding and operation scheme of an optimized hexagonal quadtree structure (OHQS) based on aperture 4 hexagonal discrete global grid systems by translation transformation. A vector model is established to describe and calculate the aperture 4 hexagonal grid system. This paper also provides two different grid code addition algorithms based on induction and ijk coordinate transformation. We implement the transformation between OHQS codes and geographic coordinates through the ij,ijk and IJK coordinate systems. Compared with existing schemes,the scheme in this paper greatly improves the efficiency of the addition operation,neighborhood retrieval and coordinate transformation,and the coding is more concise than other aperture 4 hexagonal DGGSs. The encoding operation based on the ijk coordinate system is faster than the encoding operation based on the induction and addition table. Spatial modeling based OHQS DGGSs are also provided. A case study with rainstorms demonstrated the availability of this scheme.

关键词： discrete global grid systems hexagon quadtree encoding

A novel method of determining the optimal polyhedral orientation for discrete global grid systems applicable to regionalscale areas of interest

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2020年第12期13卷 1553-1569页

作者： Jianbin Zhou Jin Ben Rui Wang Mingyang Zheng Xiaochuang Yao Lingyu Du PLA Strategic Support Force Information Engineering University ZhengzhouPeople’s Republic of China College of Land Science and Technology China Agricultural UniversityBeijingPeople’s Republic of China Troops of 31617 FuzhouPeople’s Republic of China

The polyhedral discrete global grid system(DGGS)is a multi-resolution discrete earth reference model supporting the fusion and processing of multi-source geospatial *** 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 *** date,most research has focused on global-scale applications while almost no rigorous mathematical models have been established for determining orientation *** this paper,we propose a method for determining the optimal polyhedral orientation of DGGSs for areas of interest on a regional *** proposed method avoids splitting local or regional target areas across multiple polyhedral *** the same time,it effectively handles geospatial data at a global scale because of the inherent characteristics of *** show that the orientation determined by this method successfully guarantees that target areas are located at the center of a single polyhedral *** 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.

关键词： discrete global grid systems single polyhedral face convex polygons rotate and translate cost function

GIScience research challenges for realizing discrete global grid systems as a Digital Earth

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Big Earth Data 2022年第3期6卷 358-379页

作者： Majid Hojati Colin Robertson Steven Roberts Chiranjib Chaudhuri Department of Geography and Environmental Studies Wilfrid Laurier UniversityWaterlooONCanada Coldwater Laboratory University of SaskatchewanCanmoreABCanada

Increasing data resources are available for documenting and detecting changes in environmental,ecological,and socioeconomic ***,data are distributed across a wide variety of sources(*** silos)and published in a variety of formats,scales,and semantic representations.A key issue,therefore,in building systems that can realize a vision of earth system monitoring remains data *** global grid systems(DGGSs)have emerged as a key technology that can provide a common multi-resolution spatial fabric in support of Digital Earth ***,DGGSs remain in their infancy with many technical,conceptual,and operational *** renewed interest in DGGS brought on by a recently proposed standard,the demands of big data,and growing needs for monitoring environmental changes across a variety of scales,we seek to highlight current challenges that we see as central to moving the field(s)and technologies of DGGS *** each of the identified challenges,we illustrate the issue and provide a potential solution using a reference DGGS *** articulation of these challenges,we hope to identify a clear research agenda,expand the DGGS research footprint,and provide some ideas for moving forward towards a scaleable Digital Earth *** such challenges helps the GIScience research community to achieve the real benefits of DGGS and provides DGGS an opportunity to play a role in the next generation of GIS.

关键词： DGGS discrete global grid systems GIScience Digital Earth

EASE-DGGS:a hybrid discrete global grid system for Earth sciences

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Big Earth Data 2022年第3期6卷 340-357页

作者： Jeffery A.Thompson Mary J.Brodzik Kevin A.T.Silverstein Mason A.Hurley Nathan L.Carlson Minnesota Supercomputing Institute University of MinnesotaMinneapolisMNUSA GEMS Informatics Initiative University of MinnesotaMinneapolisMNUSA National Snow and Ice Data Center Cooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderCOUSA

Although we live in an era of unprecedented quantities and access to data,deriving actionable information from raw data is a hard *** observation systems(EOS)have experienced rapid growth and uptake in recent decades,and the rate at which we obtain remotely sensed images is *** significant effort and attention has been devoted to designing systems that deliver analytics ready imagery faster,less attention has been devoted to developing analytical frameworks that enable EOS to be seamlessly integrated with other data for quantitative *** global grid systems(DGGS)have been proposed as one potential solution that addresses the challenge of geospatial data integration and ***,we propose the systematic extension of EASE-grid in order to provide DGGS-like characteristics for EOS data *** describe the extensions as well as present implementation as an application programming interface(API),which forms part of the University of Minnesota’s GEMS(Genetic x Environment x Management x Socioeconomic)Informatics Center’s API portfolio.

关键词： discrete global grid systems DGGS EASE grid coordinate reference systems