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1.
面向带洞面状对象间的拓扑关系描述模型   总被引:1,自引:1,他引:0  
为研究带洞面状对象间的拓扑关系,提出了一种25IM(25交集模型)。以点集拓扑理论为基础,对带洞面状区域的内部、边界和外部进行定义。分析了9IM(9交集模型)在表达带洞面状对象间拓扑关系方面存在的问题,将带洞面状对象分为内部、外边界、内边界、外边界外部、内边界外部共5部分,提出了一种5×5的矩阵模型,即25IM。基于点集拓扑理论,定义了8条规则来排除不符合逻辑的拓扑关系。基于25IM,对8种基本拓扑关系:相离、相接、重叠、覆盖、包含、相等、被覆盖和被包含,进行细分描述。结果表明,本文提出的25IM能够更为详细地表达带洞面状对象间的拓扑关系。  相似文献   

2.
谢俊平  杨敏华 《测绘科学》2012,(2):146-148,154
统一表达空间关系中的拓扑关系和方向关系是非常有必要的。本文首先对已有的方向模型进行分析和比较,提出了一种方向模型,即采用锥形的方法将空间参照对象的内部、边界和外部分别划分出9个方向区域,描述空间目标对象与这些方向区域的交集的情况,然后结合这种方向模型和九交模型,进而提出了一种能统一表达拓扑关系和方向关系的形式化模型。  相似文献   

3.
基于V9I的空间关系映射与操作   总被引:4,自引:0,他引:4  
利用V9I模型中目标的边界、内部和Voronoi区域均可量测及易于操作的特点 ,研究建立底层数据结构与空间关系语义层之间的V9I映射机制 ,在Voronoi的动态栅格生成算法的基础上 ,构建空间关系的基本操作。最后 ,以VC 为开发工具并采用面向对象的技术 ,设计了基于V9I的空间关系操作工具原型VTKit ,并给出部分操作实例  相似文献   

4.
针对原有方向关系矩阵模型对于参考目标MBR区域的方向描述缺陷问题,本文将拓扑约束引入方向关系定性描述,构建基于拓扑参考的方向关系定性描述模型,实现了MBR区域方向关系的有效表达。新模型首先将参考目标的MBR区域划分为不同的拓扑区域,提出方向关系拓扑参考定义;基于拓扑参考,分别对不同拓扑区域定义相应的方向关系矩阵;最后,根据参考目标与源目标间的不同拓扑关系,提出不同情况下方向关系分层定性描述策略。实验结果表明,新模型充分反映了拓扑关系对方向关系描述的约束关系,能有效提高方向关系表达的准确性和精确性。  相似文献   

5.
As an important topological relation model, the dimensionally extended 9‐intersection model (DE‐9IM) has been widely used as a basis for standards of queries in spatial databases. However, the negative conditions for the specification of the topological relations within the DE‐9IM have not been studied. The specification of the topological relations is closely related to the definition of the spatial objects and the topological relation models. The interior, boundary, and exterior of the spatial objects, including the point, line, and region, are defined. Within the framework of the DE‐9IM, 43 negative conditions are proposed to eliminate impossible topological relations. Configurations of region/region, region/line, line/line, region/point, line/point, and point/point relations are drawn. The mutual exclusion of the negative conditions is discussed, and the topological relations within the framework of 9IM and DE‐9IM are compared. The results show that: (1) impossible topological relations between spatial objects can be eliminated by the application of 43 negative conditions; and (2) 12 relations between two regions, 31 relations between a region and a line, 47 relations between two lines, three relations between a region and a point, three relations between a line and a point, and two relations between two points can be distinguished by the DE‐9IM.  相似文献   

6.
Classical topological relation expressions and computations are primarily based on abstract algebra. In this article, the representation and computation of geometry‐oriented topological relations (GOTR) are developed. GOTR is the integration of geometry and topology. The geometries are represented by blades, which contain both algebraic expressions and construction structures of the geometries in the conformal geometric algebra space. With the meet, inner, and outer products, two topology operators, the MeetOp and BoundOp operators, are developed to reveal the disjoint/intersection and inside/on‐surface/outside relations, respectively. A theoretical framework is then formulated to compute the topological relations between any pair of elementary geometries using the two operators. A multidimensional, unified and geometry‐oriented algorithm is developed to compute topological relations between geometries. With this framework, the internal results of the topological relations computation are geometries. The topological relations can be illustrated with clear geometric meanings; at the same time, it can also be modified and updated parametrically. Case studies evaluating the topological relations between 3D objects are performed. The result suggests that our model can express and compute the topological relations between objects in a symbolic and geometry‐oriented way. The method can also support topological relation series computation between objects with location or shape changes.  相似文献   

7.
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   

8.
四面体格网(TEN)模型是一种重要的空间数据构模方法,侧重于三维空间对象内部的表达,但是存在着数据量大、计算速度慢的问题。三维拓扑关系是三维GIS的重要研究内容,为此,该文提出了面向TEN的三维拓扑关系计算方法。基于点集拓扑学理论,将TEN分解为内部、边界和外部3个集合,并使用9交模型描述了TEN/TEN的8种拓扑关系;设计了面向TEN的三维拓扑关系计算流程,详细阐述了面向TEN的三维拓扑关系计算的核心算法;基于提出的三维拓扑关系算法,设计了面向TEN的拓扑关系计算实验。实验结果表明:该文提出的面向TEN的三维拓扑关系计算方法,能够满足TEN之间拓扑关系计算的需求。  相似文献   

9.
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   

10.
Introduction Inmanyapplications(CADandgeographical informationsystem,GIS),dataaremanagedby spatialdatabases,whichstorepoint,line,region objectsandspatialrelationsbetweenthem.Spa tialrelations(topologicalrelations,directionre lationsandapproximatedistancer…  相似文献   

11.
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   

12.
Representing the topological relations between directed spatial objects has gained increasing attention in recent years. Although topological relations between directed lines and other types of spatial objects, such as regions and bodies, have been widely investigated, few studies have focused on the topological relations between directed lines and directed regions. This research focuses on the representation and application of directed line–directed region (DLDR) topological relations, and may contribute to spatial querying and spatial analyses related to directed spatial objects or time‐varying objects. Compared with other topological relation models, a DLDR model that considers the starting and ending points of the directed line and the front and back faces of directed regions is proposed in this research to describe the topological relations between directed lines and directed regions. DLDR topological relations are presented, the completeness of the 111 DLDR topological relations is proved, and the topological relations based on the 9‐intersection model (9IM), 9+‐intersection model (9+‐IM), and DLDR model are compared. The formalism of the DLDR model and the corresponding geometric interpretations of the 111 DLDR topological relations are presented, seven propositions are stated to prove the completeness of the 111 DLDR topological relations, and the case study shows that more detailed topological relation information can be obtained based on the DLDR model.  相似文献   

13.
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   

14.
拓扑关系的描述和区分是建立在空间目标相互作用过程中目标集合及其分量集合拓扑特性变化基础之上的。对于两个简单面域间的空间拓扑关系描述研究已经很多,而对于带空洞的复杂面域间的空间拓扑关系的描述却相对较少。本文利用Egenhofer等提出的描述带空洞的面域间空间拓扑关系描述框架,在四交差模型的基础上,提出一种能描述带空洞的复杂面域间拓扑关系的扩展模型———D-4 ID模型,并用该模型推导了一个简单面域和一个带空洞的复杂面域间有意义的23种拓扑关系。  相似文献   

15.
模糊空间对象拓扑关系的Rough描述   总被引:3,自引:1,他引:2  
利用Rough Set理论,在四交差模型的基础上,提出适合于描述确定和模糊区域或两个模糊区域目标间拓扑空间关系的扩展模型(4-4ID模型),并且详细讨论模糊对象之间的拓扑关系。  相似文献   

16.
简单面目标与带孔洞面目标间拓扑关系的层次表达方法   总被引:1,自引:1,他引:0  
带孔洞的面目标是现实中较为常见的一类复杂目标,它们之间的拓扑关系要比简单面目标复杂得多.本文基于空间划分和目标分解的思想,利用点集(拓扑学)理论中的邻域概念详细分析和描述带孔洞面目标的点集拓扑分量,这种描述方法实质上是简单面目标点集拓扑分量描述的一种自然延展.进而,对简单面目标间拓扑关系的描述和区分方法进行了扩展,层次地分析和区分简单面目标与带孔洞面目标间的拓扑关系.相比于Egenhofer等人提出的代数描述和间接表达方法,本文提出的方法是一种直接描述和层次表达的方法,并且与简单面目标间拓扑关系的表达方法是相统一的.  相似文献   

17.
GIS不仅关心空间目标自身的时间、空间和属性特征,还必须能够处理其与所处环境间的关系。体/体拓扑关系计算是三维空间目标之间拓扑关系计算的难点,为此,本文提出一种体/体拓扑关系计算方法:基于点集拓扑理论,利用维度扩展的9交模型(DE-9IM)对体/体之间存在着的8种有意义的拓扑关系进行描述;通过比较空间目标各部分(内部、边界和外部)的交集,从而判断空间目标之间的拓扑关系;设计了一个体/体拓扑关系计算算例,对算法进行详细阐述;最后,设计了体/体拓扑关系计算实验,验证了方法的有效。  相似文献   

18.
空间方向关系的分级细节描述(英文)   总被引:1,自引:0,他引:1  
  相似文献   

19.
Consistency among parts and aggregates: A computational model   总被引:2,自引:0,他引:2  
Heterogeneous geographic databases contain multiple views of the same geographic objects at different levels of spatial resolution. When users perceive geographic objects as one spatial unit, although they are physically separated into multiple parts, appropriate methods are needed to assess the consistency among the aggregate and the parts. The critical aspect is that the overall spatial relationships with respect to other geographic objects must be preserved throughout the aggregation process. We developed a systematic model for the constraints that must hold with respect to other spatial objects when two parts of an object are aggregated. We found three sets of configurations that require increasingly more information in order to make a precise statement about their consistency: (1) configurations that are satisfied by the topological relations between the two parts and the object of interest; (2) configurations that need further information about the topological relation between the object of concern and the connector in order to be resolved unambiguously; and (3) configurations that require additional information about the topological relation between the aggregate's boundary and the boundary or interior of the object of interest to be uniquely described. The formalism extends immediately to relations between two regions with disconnected parts as well as to relations between a region and an arbitrary number of separations.  相似文献   

20.
不确定线-面拓扑关系的描述与判别   总被引:1,自引:0,他引:1  
杜晓初  黄茂军 《测绘学报》2007,36(3):340-343,350
不确定线状目标和面状目标之间拓扑关系的描述是空间信息处理过程中经常面对的问题。在对不确定线状目标和面状目标进行描述的基础上,对不确定线状目标与面状目标各组成部分之间的相交程度进行了定量表达,通过计算这些度量组成的空间向量与9-交集模型确定的空间关系向量之间的相关度,提出了一种不确定线状目标和面状目标之间拓扑关系的描述模型,通过定量的方法来对其空间拓扑关系进行判别。  相似文献   

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