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1.
1 IntroductionSpatialrelationsqueryisoneofbasicfunctionsinGIS’sapplication .MostofcurrentcommercialGISscanonlyqueryspatialrelationsforspatialob jectswithoutanyerrororuncertainty ,forexample ,tousecomputation geometryalgorithmtodeter minewhetherapointfalls…  相似文献   

2.
This paper describes the geometric and statistical properties of areal object under randomness. In order to describe formally such a uncertain topological relation, a new formal model (i. e. 4ID model) is proposed. On the basis of this, the effects of positional uncertainty on topological relations between areal objects are investigated in detail. Some possibility functions for the determination of relations are constructed based on the assumption that randomness of point location complies with a normal distribution, and the concept of uncertain sets of topological relations under randomness is introduced.  相似文献   

3.
邓敏  刘启亮  徐锐  徐枫 《测绘科学》2010,35(3):58-61
空间方位是一类重要的空间关系,它不同于目前研究较多的方向关系。空间方位关系描述的是三个目标间的空间关系,它的理论基础是基于射影几何中的三点共线不变性。本文首先阐述了空间方位的基本定义、表达基础以及它与拓扑关系、方向关系的区别。然后,重点回顾了6种较为有代表性的方位关系描述模型,指出了这些模型的适用性,并对这些模型进行了比较分析。最后,简要地分析了空间方位关系在GIS中的应用前景以及有待进一步研究的若干问题。  相似文献   

4.
Fuzziness is an internal property of spatial objects.How to model fuzziness of a spatial object is a main task of next generation GIS.This paper proposes basic fuzzy spatial object types based on fuzzy topology.These object types are the natural extension of current nonfuzzy spatial object types.A fuzzy cell complex structure is defined for modeling fuzzy regions,lines and points.Furthermore,fuzzy topological relations between these fuzzy spatial objects are formalized based on the 9intersection approach.This model can be implemented for GIS applications due to its scientific theory basis.  相似文献   

5.
在空间抽象中线状目标间拓扑关系的等价转换   总被引:2,自引:0,他引:2  
拓扑关系在抽象过程中的等价转换是维护多尺度空间关系一致性的基础。本文以空间拓扑关系组合推理所描述的线状目标之间的拓扑关系为例,采用成分抽象的等价转换方法,研究了线之间拓扑关系等价转换的原则,并绘出了相应的等价转换图。  相似文献   

6.
The advanced data mining technologies and the large quantities of remotely sensed Imagery provide a data mining opportunity with high potential for useful results. Extracting interesting patterns and rules from data sets composed of images and associated ground data can be of importance in object identification, community planning, resource discovery and other areas. In this paper, a data field is presented to express the observed spatial objects and conduct behavior mining on them. First, most of the important aspects are discussed on behavior mining and its implications for the future of data mining. Furthermore, an ideal framework of the behavior mining system is proposed in the network environment. Second, the model of behavior mining is given on the observed spatial objects, including the objects described by the first feature data field and the main feature data field by means of the potential function. Finally, a case study about object identification in public is given and analyzed. The experimental results show that the new model is feasible in behavior mining.  相似文献   

7.
The advanced data mining technologies and the large quantities of remotely sensed Imagery provide a data mining opportunity with high potential for useful results. Extracting interesting patterns and rules from data sets composed of images and associated ground data can be of importance in object identification, community planning, resource discovery and other areas. In this paper, a data field is presented to express the observed spatial objects and conduct behavior mining on them. First, most of the important aspects are discussed on behavior mining and its implications for the future of data mining. Furthermore, an ideal framework of the behavior mining system is proposed in the network environment. Second, the model of behavior mining is given on the observed spatial objects, including the objects described by the first feature data field and the main feature data field by means of the potential function. Finally, a case study about object identification in public is given and analyzed. The experimental results show that the new model is feasible in behavior mining. Supported by the National 973 Program of China(No.2006CB701305,No.2007CB310804), the National Natural Science Fundation of China (No.60743001), the Best National Thesis Fundation (No.2005047), the National New Century Excellent Talent Fundation (No.NCET-06-0618).  相似文献   

8.
针对传统9交模型对移动目标空间拓扑关系表达及量化描述的不足,基于格网化思想,提出了度量参数量化描述的方法。首先对移动目标和参考目标进行格网化,划分为固定大小的格网阵列;然后利用9交模型确定空间目标间拓扑关系的形式化描述;最后引入内部分量、边界分量、外部分量3种度量参数对移动目标空间拓扑关系进行度量化描述。试验证明,该方法计算简单、直观,能更加有效地度量移动目标间的拓扑关系。  相似文献   

9.
空间方向关系的分级细节描述   总被引:1,自引:0,他引:1  
  相似文献   

10.
多粒度的GIS数据不确定性粗集表达   总被引:6,自引:1,他引:6  
邓敏  李志林  程涛 《测绘学报》2006,35(1):64-70
粗集是一种处理地理信息不确定性和不精确性的新型数学工具,在揭示和表达多层次(或粒度)的空间知识方面具有较大优势。为此,从空间信息观测或表达的粒度角度来探讨空间数据所蕴含的不确定性。在此基础上,运用粗集理论中的一些基本概念和方法来系统地描述和表达空间目标位置数据、属性数据以及空间关系数据的不确定性,旨在建立一种多粒度的不确定性分析和表达方法。  相似文献   

11.
ABSTRACT

There is growing interest in globally modelling the entire planet. Although topological relations between spherical simple regions and topological relations between regions with holes in the plane have been investigated, few studies have focused on the topological relations between spherical spatial regions with holes. The 16-intersection model (16IM) is proposed to describe the topological relations between spatial regions with holes. A total of 25 negative conditions are proposed to eliminate the impossible topological relations between spherical spatial regions with holes. The results show that (1) 3 disjoint relations, 3 meet relations, 66 overlap relations, 7 cover relations, 3 contain relations, 1 equal relation, 7 coveredBy relations, 3 inside relations, 1 attach relation, 52 entwined relations, and 28 embrace relations can be distinguished by the 16IM and that (2) the formalisms of attach, entwined, and embrace relations between the spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on the simplified 16IM are different, whereas the formalisms of other types of relations between spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on a simplified 16IM are the same.  相似文献   

12.
矿山地理信息系统中巷道模型的研究   总被引:11,自引:0,他引:11  
在深入分析矿册测量信息的基础上,提出了组成矿井巷道的4种基本元素,然后用C^++语言描述了面向对象的矿井巷道数据模型,并分析了所包含的拓扑关系,矿井测量信息管理子系统的开发成功说明了本文所提出了数据模型和数据结构的合理性与可行性。  相似文献   

13.
Direction is a common spatial concept that is used in our daily life. It is frequently used as a selection condition in spatial queries. As a result, it is important for spatial databases to provide a mechanism for modeling and processing direction queries and reasoning. Depending on the direction relation matrix, an inverted direction relation matrix and the concept of direction pre- dominance are proposed to improve the detection of direction relation between objects. Direction predicates of spatial systems are also extended. These techniques can improve the veracity of direction queries and reasoning. Experiments show excellent efficiency and performance in view of direction queries.  相似文献   

14.
Direction is a common spatial concept that is used in our daily life. It is frequently used as a selection condition in spatial queries. As a result, it is important for spatial databases to provide a mechanism for modeling and processing direction queries and reasoning. Depending on the direction relation matrix, an inverted direction relation matrix and the concept of direction pre- dominance are proposed to improve the detection of direction relation between objects. Direction predicates of spatial systems are also extended. These techniques can improve the veracity of direction queries and reasoning. Experiments show excellent efficiency and performance in view of direction queries.  相似文献   

15.
3D GIS中空间对象的存储与快速查询   总被引:2,自引:0,他引:2  
张永玉  马劲松  刘艳 《测绘科学》2009,34(4):147-149
空间对象的存储和快速查询是三维地理信息系统研究的基本问题。本文采用面向对象的方法将三维空间对象抽象为点、线、面、体四类,点对象用一个坐标点(x,y,z)来表示,线对象用一组首尾相接的线段表示,面对象与体对象用三角网表示,然后采用SQL Server 2005来组织存储数据。为了提高空间数据库的检索速度,作者编程实现了线性八叉树空间索引,应用程序采用目前比较流行的ADO.net技术来访问数据库。  相似文献   

16.
Introduction Inmanyapplications(CADandgeographical informationsystem,GIS),dataaremanagedby spatialdatabases,whichstorepoint,line,region objectsandspatialrelationsbetweenthem.Spa tialrelations(topologicalrelations,directionre lationsandapproximatedistancer…  相似文献   

17.
Because SQL for querying data from spatial databases is ineffective, the query based on natural or visual language becomes an attractive research field gradually. However, how to define and represent natural languages related to spatial data are still gigantic problems. Because existing models of direction relations can't describe by use of some common concepts. First of all, detailed direction relations are proposed to describe the directions related to the interior of spatial objects, such as “east part of a region”, “east boundary of a region”, and so on. Secondly, by integrating the detailed directions with exterior direction relations and topological relations, several NLSRs are defined, such as “a road goes across the east part of a lake”, “a river goes along the east boundary of a province”, etc. Finally, based on the NLSRs abovementioned, a natural spatial query language (NSQL) is formed to retrieve data from spatial databases.  相似文献   

18.
This paper presents a study on the modeling of fuzzy topological relations between uncertain objects in Geographic Information Systems (GIS). Based on the recently developed concept of computational fuzzy topological space, topological relations between simple fuzzy spatial objects are modeled. The fuzzy spatial objects here cover simple fuzzy region, simple fuzzy line segment and fuzzy point. To compute the topological relations between the simple spatial objects, intersection concepts and integration methods are applied and a computational 9-intersection model are proposed and developed. There are different types of intersection, and we have proposed different integration methods for computation in different cases. For example, surface integration method is applied to the case of the fuzzy region-to-fuzzy region relation, while the line integration method is used in the case of fuzzy line segment-to-fuzzy line segment relation. Moreover, this study has discovered that there are (a) sixteen topological relations between simple fuzzy region to line segment; (b) forty-six topological relations between simple fuzzy line segments; (c) three topological relations between simple fuzzy region to fuzzy point; and (d) three topological relations between simple fuzzy line segment to fuzzy point.  相似文献   

19.
利用四叉树索引,提出一种基于方向和距离关系的复合空间查询算法.其基本思路是:计算给定的方向区域和距离范围之间的交S,借助四叉树索引快速查找其MBR(Minimum Bounding Rectangle)被S包含或与S相交的空间对象,构成候选集,从候选集中删除不符合给定方向和距离关系的空间对象,得到查询结果.实验表明,算法具有较好的空间查询性能.  相似文献   

20.
多尺度表达中空间拓扑关系等价性评价模型   总被引:2,自引:2,他引:2  
本文主要讨论不同尺度下地理目标之间拓扑关系的等价性问题。根据人类认知习惯,得出从大比例尺地理空间中拓扑关系抽象为小比例尺空间中拓扑关系应当遵循的基本规则,并利用模糊函数将这些规则定量化;在此基础上,得到评价地理空间场景中多个空间目标之间拓扑关系在不同尺度下是否等价的综合评价模型。该模型可以用于检验和维护空间数据质量、为地图自动综合提供空间关系处理和评价方法的参考。  相似文献   

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