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1.
多尺度地图空间相似关系基本问题研究   总被引:8,自引:0,他引:8  
基于多尺度地图数据库建设中地图自动综合的终止判断条件,引出多尺度地图空间相似关系问题。基于集合论给出空间相似关系的定义,论述空间相似关系的5个性质,即反身性、对称性、非传递性、多尺度自相似性与尺度依赖性;并从图形相似和属性相似的角度论述多尺度地图空间相似关系的分类体系。该成果是研究地图自动综合和地图空间相似查询等的基础。  相似文献   

2.
空间目标处于一定的时间与空间中,时态拓扑关系和空间拓扑关系经常交织在一起,形成时空拓扑关系,因此有必要在统一框架下研究时空拓扑关系.基于Allen对时态拓扑关系和Egenhofer对空间拓扑关系的研究,对时态拓扑关系和空间拓扑关系分别采用3×3的矩阵进行描述,将时空拓扑关系表示为3×6的矩阵,并描述了简单面/面之间的104种时空拓扑关系.在研究时态拓扑关系推理和空间拓扑关系推理的基础上,提出了一种时空拓扑关系推理方法.该文提出的时空拓扑关系描述和推理方法对于拓展时空拓扑关系的研究具有重要意义.  相似文献   

3.
地理空间中的空间关系表达和推理   总被引:5,自引:2,他引:5  
针对地理空间中的应用,归纳了在空间关系的表达与推理中不同于人工智能领域研究的一些特点:在人工智能领域,更注重建立形式化的推理系统;而在地理信息科学中,则需更关注地理空间的特点以及地物的地理语义。该文基于地理空间和地理现象的本质且顾及地理空间认知,总结了地理空间中空间关系表达和推理的特点,具体包括空间的有限性、地球的球面特征、地物的地理语义、地物形状的复杂性、面状地物、特殊的空间关系、空间关系的层次性与尺度相应原则、不确定性、三维与时态特性九方面;进而介绍了地理空间关系表达的两个应用,即地理信息检索和基于对象的图像分析。该文的探讨可为地理信息科学中的相关研究提供方向性指导。  相似文献   

4.
栅格空间中三维地学实体拓扑关系表达的K6N9-I模型   总被引:1,自引:0,他引:1  
论述栅格空间中三维地学实体拓扑空间关系研究的理论基础和现实意义,基于数字拓扑理论定义了栅格实体的6邻域内部I6、6邻域边界B6和k阶6邻域E6k,并以此分别替换9-I模型中实体的内部I、边界B和外部E,形成一种适用于栅格空间三维实体拓扑关系描述和分析的新9-I模型,即k阶6邻9-I模型(K6N9-I)。以基于规则六面体表达的地学实体为研究对象,通过扩展关系数据库SQL形成空间关系查询语言,实现了栅格空间中三维地学实体拓扑关系的定性表示和定量计算。以若干地学实体为例进行了初步实验,表明该模型实用方便,且在复杂地学实体的度量、方位等空间关系研究方面亦有较好的应用前景。  相似文献   

5.
空间关系理论研究是当前GIS界重点研究的前沿课题之一,但就目前研究成果看,空间关系理论中的拓扑关系和方向关系的理论研究多采用独立的描述模型,影响了空间推理和空间表达的精度。该文在分析拓扑关系和方向关系描述模型的基础上,提出将拓扑关系和方向关系定性表示相结合的TD模型,并用实例说明该模型能较全面地描述空间对象的空间关系。  相似文献   

6.
针对ArcGIS软件复杂钻孔三维精细地质模型自动构建研究存在的不足,该文在简要分析MultiPatch三维空间数据模型和深入研究复杂钻孔三维空间精确定位方法的基础上,探讨了基于ArcGIS Engine的复杂钻孔三维精细地质模型自动构建工作流程,并从空间精确定位、属性精细表达两个层面对钻孔三维精细地质模型构建算法进行了设计与实现.经软件功能研发及实际应用检验表明,该研究能够有效实现复杂钻孔精细地质属性特征的三维空间精确定位及多尺度精细表达,为应用ArcGIS Engine自动构建复杂钻孔三维精细地质模型提供了一种新的有效途径,也可为基于ArcGIS Engine的复杂地质体三维可视化建模及精细地质属性表达研究提供应用借鉴.  相似文献   

7.
目前的三维地质体空间关系模型表达能力较弱,限制了其在空间分析、查询等方面的应用。三维模型的应用与发展迫切需要一种新的底层分解与理论建模解决此类问题。该文基于凸凹理论重新对地质体进行结构定义与空间关系建模,提出了内凸体、外凸体、内缘体、外缘体等构造,并在此基础上建立了三维地质体R7×7空间关系模型,将地质体间空间关系表达能力理论上扩充至249种,实际能够表达40余种空间关系;给出了包容、镶嵌、部分镶嵌等关系的定义并对其进行了模型表达;针对不同应用,给出了R7×7模型的变换模型R(5×5 3×3)等。为能够表达地质体交集的边界长度、交面面积、地质体体积、外缘体体积、镶嵌体积等地质空间重要关系,基于凸凹理论建立了地质体度量关系模型,是矿区地质体拓扑关系查询、空间分析推理等应用的基础模型。给出了模型与地质体模糊理论的相契性分析,二者模型能够相辅相成,相互借鉴使用。  相似文献   

8.
多尺度地理空间点群目标相似关系的计算研究   总被引:1,自引:0,他引:1  
研究多尺度地理空间点群目标相似关系的计算问题.基于4类点群信息,将点群目标包含的信息重新分成统计信息、专题信息、拓扑信息、几何信息和度量信息,这5类信息是影响点群相似性程度的主要因子.根据这5类信息描述参数的特点,给出了各个因子的相似度计算公式,建立了多尺度地理空间点群目标相似关系的计算模型,并通过算例验证了该模型的可行性与有效性,为地图综合质量的评价提供了一种新方法.  相似文献   

9.
三维地籍空间拓扑关系是三维空间拓扑关系在地籍领域的应用,随着三维地籍的发展和地籍数据应用范围的拓展,三维地籍空间拓扑关系的重要性日益凸显。该文在总结地籍空间拓扑关系和三维空间拓扑关系研究现状的基础上,讨论了三维地籍空间建模对象和空间数据特征,并以此为基础分析总结了三维地籍空间拓扑关系的特征,提出了三维地籍空间拓扑关系类型分类方法。依据地籍对象几何维度的不同,将三维地籍空间拓扑关系划分为10个类别,对每个类别中拓扑关系进行详细划分后得到82种三维地籍空间拓扑关系类型。三维地籍空间拓扑关系分类研究成果可以为三维地籍空间拓扑关系分析与计算、地籍宗地更新、地籍空间数据拓扑一致性检验等提供研究基础。  相似文献   

10.
空间数据的多尺度表达问题已成为GIS研究的重点,也是地图自动综合的瓶颈。智能化的多尺度表达是亟须解决的问题。利用小波分析中的多分辨率分析原理,建立微分角度的线状要素简化模型,结合空间要素多尺度表达的特征,研究空间线状要素的简化方法,并对简化后的图形拓扑一致性做简单分析,实现线状要素的简化。  相似文献   

11.
基于场所的GIS研究   总被引:2,自引:2,他引:0  
探讨从地理空间认知出发,实现基于场所的GIS(PB—GIS)的相关问题。PB—GIS以场所为核心,显式表达地理空间知识,并遵循特定规则进行定性空间推理,从而服务于空间行为决策。比较PB—GIS与基于坐标的GIS(CB—GIS)之间的差异和适合解决的问题,并描述定性空间推理的特点及其在PB—GIS中的应用。在分析实现PB—GIS的关键技术基础上,采用三层架构设计了一个PB-GIS的概念体系结构。  相似文献   

12.
空间推理是空间信息智能化处理的难题之一,目前的空间推理过程缺乏柔性化与智能化的一个重要原因就是不能有效利用常识。该文中阐述常识、常识推理及常识的表示,研究空间推理、基于常识的空间推理的关键技术及其在空间信息处理中的作用。最后结合基于常识的空间推理的空间可视性分析示例,提出利用空间常识提高空间信息处理系统智能性的思路。  相似文献   

13.
This research is motivated by the need for 3D GIS data models that allow for 3D spatial query, analysis and visualization of the subunits and internal network structure of ‘micro‐spatial environments’ (the 3D spatial structure within buildings). It explores a new way of representing the topological relationships among 3D geographical features such as buildings and their internal partitions or subunits. The 3D topological data model is called the combinatorial data model (CDM). It is a logical data model that simplifies and abstracts the complex topological relationships among 3D features through a hierarchical network structure called the node‐relation structure (NRS). This logical network structure is abstracted by using the property of Poincaré duality. It is modelled and presented in the paper using graph‐theoretic formalisms. The model was implemented with real data for evaluating its effectiveness for performing 3D spatial queries and visualization.  相似文献   

14.
The abstraction, representation, and computation of entity–space relationship are keystones of geographic information science (GIS). The newly proposed spatial chromatic tessellation (SCT) provides a novel model to explore this relationship. SCT has demonstrated a variety of potential applications in GIS, such as reasoning spatial topology, point pattern analysis, and Voronoi diagrams. This study aims to theoretically investigate SCT by focusing on two aspects: (1) extending SCT to higher dimensional spaces. Results show that cells missing in lower dimensional spaces are hidden in higher dimensional spaces; (2) exploring the uniqueness of chromatic codes, particularly the chromatic codes of 2-cell and 3-cell clusters: their codes are proved to be unique. In a mathematical perspective, the observed phenomena from the above two aspects bring some new thoughts into the first law of geography and spatial heterogeneity. Based on these new understandings of entity–space relationship, SCT is replaced by spatial chromatic model (SCM) in which spaces are created by entities themselves rather than by partitioning the space preexisted. This makes a change from an absolute geographic space to a relative geographic space.  相似文献   

15.
Three-dimensional (3D) building models are essential for 3D Geographic Information Systems and play an important role in various urban management applications. Although several light detection and ranging (LiDAR) data-based reconstruction approaches have made significant advances toward the fully automatic generation of 3D building models, the process is still tedious and time-consuming, especially for massive point clouds. This paper introduces a new framework that utilizes a spatial database to achieve high performance via parallel computation for fully automatic 3D building roof reconstruction from airborne LiDAR data. The framework integrates data-driven and model-driven methods to produce building roof models of the primary structure with detailed features. The framework is composed of five major components: (1) a density-based clustering algorithm to segment individual buildings, (2) an improved boundary-tracing algorithm, (3) a hybrid method for segmenting planar patches that selects seed points in parameter space and grows the regions in spatial space, (4) a boundary regularization approach that considers outliers and (5) a method for reconstructing the topological and geometrical information of building roofs using the intersections of planar patches. The entire process is based on a spatial database, which has the following advantages: (a) managing and querying data efficiently, especially for millions of LiDAR points, (b) utilizing the spatial analysis functions provided by the system, reducing tedious and time-consuming computation, and (c) using parallel computing while reconstructing 3D building roof models, improving performance.  相似文献   

16.
This study examined the relationships between geospatial thinking and spatial ability, focusing on knowledge and reasoning about fundamental concepts in geospatial science. Scores on a geospatial thinking test had low correlations with each other, compared to high correlations among scores on spatial ability tests, and the degrees of relationship between geospatial thinking and spatial ability depended on the type of geospatial thinking. Expert geospatial scientists did not outperform students on spatial ability tests, suggesting that expertise in geospatial science might not simply be explained by superiority in spatial ability. The results point to the necessity of targeted instruction for geospatial learning.  相似文献   

17.
Abstract

A simple, exemplary system is described that performs reasoning about the spatial relationships between members of a set of spatial objects. The main problem of interest is to make sound and complete inferences about the set of all spatial relationships that hold between the objects, given prior information about a subset of the relationships. The spatial inferences are formalized within the framework of relation algebra and procedurally implemented in terms of constraint satisfaction procedures. Although the approach is general, the particular example employs a new ‘complete’ set of topological relationships that have been published elsewhere. In particular, a relation algebra for these topological relations is developed and a computational implementation of this algebra is described. Systems with such reasoning capabilities have many applications in geographical analysis and could be usefully incorporated into geographical information systems and related systems.  相似文献   

18.
基于WebMGIS的矿山安全实时监测集成系统及其应用   总被引:5,自引:0,他引:5  
矿山安全实时监测对矿山安全与防灾减灾具有重要的意义。该文在分析当前国内矿山GIS(MGIS)、矿山安全监测系统(MSMS)研究与应用现状的基础上,指出MGIS与MSMS在企业网上进行集成的必要,提出了统一的时空框架下系统集成后的功能和总体结构,论述系统集成中的开发方法选择、时空数据组织、空间数据接口、数据库访问方法及页面更新等问题,最后对该系统在开滦林南仓的成功应用作了简要介绍。  相似文献   

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