OGC Web Map Service is one kind of OGC Portrayal Services belongs to OGC Web Service model and it provides multi\|platform interoperability of spatial data set. This paper presents a method for implementing OGC Web Ma...OGC Web Map Service is one kind of OGC Portrayal Services belongs to OGC Web Service model and it provides multi\|platform interoperability of spatial data set. This paper presents a method for implementing OGC Web Map Service based on Web Service technique and introduces the detailed process.展开更多
This paper discusses the features and relevant theories of GIS spatial data model based on hypergraph,etc.The integrated concept model based on hypergraph and object_oriented model (HOOM) is proposed by the authors.Th...This paper discusses the features and relevant theories of GIS spatial data model based on hypergraph,etc.The integrated concept model based on hypergraph and object_oriented model (HOOM) is proposed by the authors.The principal contribution of this paper is that we study the K_section and other theories of hypergraph.An application example using HOOM is given at the end of the paper.展开更多
Up to now, detailedstrategies and algorithms of automaticchange detection for road networksbased on GIS have not been discussed.This paper discusses two differentstrategies of automatic change detec-tion for images wi...Up to now, detailedstrategies and algorithms of automaticchange detection for road networksbased on GIS have not been discussed.This paper discusses two differentstrategies of automatic change detec-tion for images with low resolution andhigh resolution using old GIS data,and presents a buffer detection andtracing algorithm for detecting roadfrom low-resolution images and a newprofile tracing algorithm for detectingroad from high-resolution images. Forfeature-level change detection (FL-CD), a so-called buffer detection algo-rithm is proposed to detect changes offeatures. Some ideas and algorithms ofusing GIS prior information and somecontext information such as substructures of road in high-resolution imagesto assist road detection and extractionare described in detail.展开更多
3D spatial data model and simulating are the core of 3D GIS can be adopted indifferent domains. A data model based on Quasi Tri-Prism Volume (QTPV) has been proposed. QTPVdefinition and its special cases have been dis...3D spatial data model and simulating are the core of 3D GIS can be adopted indifferent domains. A data model based on Quasi Tri-Prism Volume (QTPV) has been proposed. QTPVdefinition and its special cases have been discussed. Using QTPV and its special cases, irregularnatural geological bodies and regular subsurface engineering can be described efficiently. Theproposed model is composed of five primitives and six objects. Data structures and topologicalrelationship of the fives primitives and three objects describing stratigraphy are designed indetail. Some schemes are designed for the QTPV modelling of stratigraphy and subsurface engineeringaccording to modelling data. The model manipulation method of QTPV cutting by an arbitrary plane isdiscussed. Using VC^(++)6. 0 programming language integrated with SQL database and OpenGL graphiclibrary under windows environment, a system prototype 3DGeoMV has been developed. The experimentresult shows that the QTPV model is feasible and efficient in modelling subsurface engineering.展开更多
This paper compares the differences between the mathematical model in graph theory and GIS network analysis model. Thus it claims that the GIS network analysis model needs to solve. Then this paper introduces the spat...This paper compares the differences between the mathematical model in graph theory and GIS network analysis model. Thus it claims that the GIS network analysis model needs to solve. Then this paper introduces the spatial data management methods in object\|relation database for GIS and discusses its effects on the network analysis model. Finally it puts forward the GIS network analysis model based on the object\|relation database. The structure of the model is introduced in detail and research is done to the internal and external memory data structure of the model. The results show that it performs well in practice.展开更多
This paper presents a component object model (COM) based framework for managing, analyzing and visualizing massive multi-scale digital elevation models (DEMs). The framework consists of a data management component (DM...This paper presents a component object model (COM) based framework for managing, analyzing and visualizing massive multi-scale digital elevation models (DEMs). The framework consists of a data management component (DMC), which is based on RDBMS/ORDBMS, a data analysis component (DAC) and a data render component (DRC). DMC can manage massive multi-scale data expressed at various reference frames within a pyramid database and can support fast access to data at variable resolution. DAC integrates many useful applied analytic functions whose results can be overlaid with the 3D scene rendered by DRC. DRC provides view-dependent data paging with the support of the underlying DMC and organizes the potential visible data at different levels into rendering.展开更多
文摘OGC Web Map Service is one kind of OGC Portrayal Services belongs to OGC Web Service model and it provides multi\|platform interoperability of spatial data set. This paper presents a method for implementing OGC Web Map Service based on Web Service technique and introduces the detailed process.
文摘This paper discusses the features and relevant theories of GIS spatial data model based on hypergraph,etc.The integrated concept model based on hypergraph and object_oriented model (HOOM) is proposed by the authors.The principal contribution of this paper is that we study the K_section and other theories of hypergraph.An application example using HOOM is given at the end of the paper.
基金the Open Research Fund Program of LIESMARS of Wuhan University (No. (01)0304).
文摘Up to now, detailedstrategies and algorithms of automaticchange detection for road networksbased on GIS have not been discussed.This paper discusses two differentstrategies of automatic change detec-tion for images with low resolution andhigh resolution using old GIS data,and presents a buffer detection andtracing algorithm for detecting roadfrom low-resolution images and a newprofile tracing algorithm for detectingroad from high-resolution images. Forfeature-level change detection (FL-CD), a so-called buffer detection algo-rithm is proposed to detect changes offeatures. Some ideas and algorithms ofusing GIS prior information and somecontext information such as substructures of road in high-resolution imagesto assist road detection and extractionare described in detail.
基金Funded by the Hong Kong Polytechnic University ASD research fund (No. 1.34.A222),Open Research Fund Program of LIESMARS (No. WKL(01) 0302) and the National Natural Science Foundation of China(No. 40401021)
文摘3D spatial data model and simulating are the core of 3D GIS can be adopted indifferent domains. A data model based on Quasi Tri-Prism Volume (QTPV) has been proposed. QTPVdefinition and its special cases have been discussed. Using QTPV and its special cases, irregularnatural geological bodies and regular subsurface engineering can be described efficiently. Theproposed model is composed of five primitives and six objects. Data structures and topologicalrelationship of the fives primitives and three objects describing stratigraphy are designed indetail. Some schemes are designed for the QTPV modelling of stratigraphy and subsurface engineeringaccording to modelling data. The model manipulation method of QTPV cutting by an arbitrary plane isdiscussed. Using VC^(++)6. 0 programming language integrated with SQL database and OpenGL graphiclibrary under windows environment, a system prototype 3DGeoMV has been developed. The experimentresult shows that the QTPV model is feasible and efficient in modelling subsurface engineering.
文摘This paper compares the differences between the mathematical model in graph theory and GIS network analysis model. Thus it claims that the GIS network analysis model needs to solve. Then this paper introduces the spatial data management methods in object\|relation database for GIS and discusses its effects on the network analysis model. Finally it puts forward the GIS network analysis model based on the object\|relation database. The structure of the model is introduced in detail and research is done to the internal and external memory data structure of the model. The results show that it performs well in practice.
文摘This paper presents a component object model (COM) based framework for managing, analyzing and visualizing massive multi-scale digital elevation models (DEMs). The framework consists of a data management component (DMC), which is based on RDBMS/ORDBMS, a data analysis component (DAC) and a data render component (DRC). DMC can manage massive multi-scale data expressed at various reference frames within a pyramid database and can support fast access to data at variable resolution. DAC integrates many useful applied analytic functions whose results can be overlaid with the 3D scene rendered by DRC. DRC provides view-dependent data paging with the support of the underlying DMC and organizes the potential visible data at different levels into rendering.