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1.
线面拓扑和度量关系的细分描述和计算方法   总被引:1,自引:0,他引:1  
由于单独的拓扑关系、度量关系无法区分复杂要素之间的空间关系,在语义描述上存在歧义,提出一种二维空间R~2下空间关系的细分表达模型.该模型将面与线求交后,线面可以表示成n-1个拓扑和度量分量的序列矩阵,在语义上进行更细致的分段描述;采用折线节点微小圆求交的算法,考虑面带洞和目标的不确定性,归纳出线面拓扑关系细分判断的7个规则,以及长度、分割度等度量项的计算方法.最后以土地利用中图斑扣除线状地物计算地类面积为实例,验证了该模型和计算方法对解决实际问题的有效性.  相似文献   

2.
Topological relations have played important roles in spatial query, analysis and reasoning. In a two-dimensional space (IR2), most existing topological models can distinguish the eight basic topological relations between two spatial regions. Due to the arbitrariness and complexity of topological relations between spatial regions, it is difficult for these models to describe the order property of transformations among the topological relations, which is important for detailed analysis of spatial relations. In order to overcome the insufficiency in existing models, a multi-level modeling approach is employed to describe all the necessary details of region–region relations based upon topological invariants. In this approach, a set of hierarchically topological invariants is defined based upon the boundary–boundary intersection set (BBIS) of two involved regions. These topological invariants are classified into three levels based upon spatial set concept proposed, which include content, dimension and separation number at the set level, the element type at the element level, and the sequence at the integrated level. Corresponding to these hierarchical invariants, multi-level formal models of topological relations between spatial regions are built. A practical example is provided to illustrate the use of the approach presented in this paper.
Zhilin LiEmail:
  相似文献   

3.
数据更新中要素变化检测与匹配方法   总被引:4,自引:0,他引:4  
吴建华  傅仲良 《计算机应用》2008,28(6):1612-1615
在要素类之间缺乏同名实体关联关系的情况下,通过空间分析自动识别出当前要素的同名实体及它们之间的变化信息。在查询当前要素的候选匹配集时,设计了一种基于自定义空间拓扑关系的空间查询方法,缩小了的空间查询范围并减少了查询次数,提高了空间分析的效率;在确定当前要素的同名实体时,提出了基于权重的空间要素相似性计算模型,基于该模型有效地对复杂空间关系下的要素进行了匹配,提高了匹配的准确性。  相似文献   

4.
随时间演化的不确定区域间拓扑关系判定   总被引:1,自引:0,他引:1       下载免费PDF全文
不确定性处理是时空数据库技术研究的新领域,现有研究成果集中在时空不确定性的表示模型方面,缺乏不确定性对象间时空关系特别是拓扑关系的分析.提出了利用3维拓扑分析模型来分析2维运动对象的时空关系,针对随时间演化的2维不确定性区域,将Egg/Yolk模型中的RCC(region connection calculus)区域扩充至3维,得到46种联合完备且互不相交的基本拓扑关系,根据各基本拓扑关系的时空特性,将46种基本关系归类为21类不确定性时空关系.  相似文献   

5.
矢量路网的二维图像表达旨在建立道路到图像的转化关系,对于道路交通流预测等实际问题具有重要研究价值。针对目前研究存在的空间拓扑关系丢失和图像分辨率不易确定等问题,提出了一种矢量路网的自适应二维图像表达方法。该方法能够自适应不同路网结构,在最大维持矢量路网拓扑关系的前提下,将道路路段一一映射到像素单元上,从而生成矢量路网的紧凑二维图像。选取国内外数百个城市不同类型的矢量路网对算法的性能进行验证,通过与随机编码和顺序编码的结果进行对比,证明了该方法的有效性与合理性。  相似文献   

6.
 The development of formal models of spatial relations is a topic of great importance in spatial reasoning, geographic information systems (GIS) and computer vision, and has gained much attention from researchers across these research areas during the past two decades. In recent years significant achievements have been made on the development of models of spatial relations between spatial objects with precisely defined boundaries. However, these models cannot be directly applied to spatial objects with indeterminate boundaries which are found in many applications in geographic analysis and image understanding. This article develops a method for approximately analyzing binary topological relations between geographic regions with indeterminate boundaries based upon previous work on topological spatial relations and fuzzy sets. In addition, examples are given to demonstrate the method and related concepts. It is shown that the eight binary topological relations between regions in a two-dimensional space can be easily determined by the method.  相似文献   

7.
李成  毕笃彦 《计算机工程》2007,33(19):158-160,
通过对空间数据的拓扑一致性问题的分析,给出了一种基于拓扑的空间数据模型,在此基础上提出了一种空间拓扑规则发现机制.利用所得的空间拓扑规则,判断空间数据是否具有拓扑不一致性,进而采取相应的策略进行拓扑一致性维护,以提高空间数据的质量.  相似文献   

8.
基于规则的空间一致性维护   总被引:2,自引:0,他引:2       下载免费PDF全文
通过对空间数据的拓扑一致性问题的分析,给出了一种基于拓扑的空间数据模型,在此基础上提出了一种空间拓扑规则发现机制。利用所得的空间拓扑规则,判断空间数据是否具有拓扑不一致性,进而采取相应的策略进行拓扑一致性维护,以提高空间数据的质量。  相似文献   

9.
基于MapObjects的空间拓扑关系的建立   总被引:4,自引:0,他引:4  
吴其昌  陈天泽  粟毅 《计算机仿真》2005,22(1):73-75,83
MO(MapObjects)是广泛应用于GIS软件开发的组件,但是它的数据模型的局限性决定了它不能够独立支持空间拓扑关系。而空间拓扑关系是GIS中空间分析的基础,从而限制了它在空间分析方面的应用。该文针对MO不能独立支持空间拓扑关系的问题,分析了空间拓扑关系和MO的空间数据模型,设计了用于存储拓扑关系数据的数据库,给出了建立空间拓扑关系的过程,提出并实现了一种基于MO的空间拓扑关系的建立方法,扩展了MO的空间分析功能,拓展了MO的应用范围。  相似文献   

10.
拓扑多边形自动构建的一种改进算法   总被引:3,自引:0,他引:3  
多边形的构建是地理数据拓扑关系建立的难点之一,其算法的自动化、速度和复杂性一直是GIS界研究的一个重点。在分析文献犤6犦算法局限性的基础上,根据解析几何的原理,提出了一种基于方位角计算的拓扑多边形自动构建的改进算法,较好地解决了多边形构建中弧段断开处理和多边形拓扑关系确定的问题。所提算法结构清晰、简单易懂,且程序容易实现。  相似文献   

11.
Topological analysis of 3D building models using a spatial query language   总被引:1,自引:0,他引:1  
The paper presents parts of the development of a spatial query language for building information models. Such a query language enables the spatial analysis of building information models and the extraction of partial models that fulfill certain spatial constraints. Among other features, it includes topological operators, i.e. operators that reflect the topological relationships between 3D spatial objects. The paper presents definitions of the semantics of the topological operators within, contain, touch, overlap, disjoint and equal in 3D space by using the 9-intersection model. It further describes a possible implementation of the topological operators by means of an octree-based algorithm. The recursive algorithm presented in this article relies on a breadth-first traversal of the operands’ octree representations and the application of rules that are based on the color of the octants under examination. Because it successively increases the discrete resolution of the spatial objects employed, the algorithm enables the user on the one hand to handle topological relationships in a fuzzy manner and on the other hand to trade-off between computational effort and the required accuracy. The article also presents detailed investigations on the runtime performance of the developed algorithm.  相似文献   

12.
本文提出了一种新型的拓扑地图,该地图用激光的扇区特征和视觉的比例不变特征(SIFT)来联合表示节点。与传统地图相比,该地图在创建过程中不依赖任何人工路标和机器人的全局定位。机器人通过综合考虑单个节点的相似度和不同节点间的空间关系,利用隐马尔可夫模型来提高节点识别的准确率。实验表明,本文的拓扑地图不仅易于创建和维护,而且适用于机器人在大规模室内环境下的自主导航。  相似文献   

13.
Weighted walkthroughs are a quantitative model for representing the spatial relation between two raster features in image databases. In this paper, we establish a correspondence between the weighted walkthroughs and qualitative models for spatial reasoning. We provide rules for estimating qualitative geometric properties and topological relations from the quantitative data that are computed for each pair of pixel sets. The approach has been tested through experiments with raster regions.  相似文献   

14.
空间区域拓扑关系分析方法综述   总被引:19,自引:2,他引:19       下载免费PDF全文
虞强源  刘大有  谢琦 《软件学报》2003,14(4):777-782
空间关系形式化模型的发展是空间推理、地理信息系统(geographic information systems,简称GIS)、计算机视觉等领域中的一个非常重要的主题,近年来受到相关领域研究者的极大关注,特别是在空间区域间拓扑关系模型的研究方面取得了很大进展.介绍了区域间拓扑关系形式化分析的主要研究内容、研究方法和研究进展,并探讨了目前存在的问题和今后的发展方向.  相似文献   

15.
高勇  刘瑜  邬伦  朱晓禧 《计算机工程》2007,33(22):57-59
针对二维欧氏空间内的平面移动点对象,该文基于“9交模型”,定义了参考地物的空间拓扑关系模型,并将该模型表示为3个连续观测时刻的拓扑关系的三元组,给出了移动点对象与参考点、线和面地物的空间拓扑关系的定性表达。该模型可以清楚地刻画移动点对象相对于参考地物的运动变化情况,对于智能交通、移动位置服务等应用具有重要的意义。  相似文献   

16.
针对图像数据库中空间查询的需求,将拓扑关系和方向关系结合,在二维投影间隔空间关系模型基础上,提出了一种新的拓扑、方向关系的度量方法。所提出的度量方法提高了空间关系相似性的度量精度,从而有效地提高了图象对象空间关系查询的准确性。  相似文献   

17.
利用简化9交模型进行三维拓扑分析   总被引:2,自引:0,他引:2  
针对点、线、面和体等简单空间对象提出新的否定规则,对9交模型进行了简化.利用简化后的9交模型,仅需分析4组相交关系即可得出实际拓扑关系.在此基础上构建了拓扑关系推导表,可进一步分析复合空间对象之间的拓扑关系,并以线与体之间拓扑关系为例讨论了算法实现.与已有的算法相比,该算法能分析更为复杂的空间对象之间的拓扑关系.  相似文献   

18.
Basic Topological Models for Spatial Entities in 3-Dimensional Space   总被引:6,自引:0,他引:6  
In recent years, models of spatial relations, especially topological relations, have attracted much attention from the GIS community. In this paper, some basic topologic models for spatial entities in both vector and raster spaces are discussed.It has been suggested that, in vector space, an open set in 1-D space may not be an open set any more in 2-D and 3-D spaces. Similarly, an open set in 2-D vector space may also not be an open set any more in 3-D vector spaces. As a result, fundamental topological concepts such as boundary and interior are not valid any more when a lower dimensional spatial entity is embedded in higher dimensional space. For example, in 2-D, a line has no interior and the line itself (not its two end-points) forms a boundary. Failure to recognize this fundamental topological property will lead to topological paradox. It has also been stated that the topological models for raster entities are different in Z 2 and R 2. There are different types of possible boundaries depending on the definition of adjacency or connectedness. If connectedness is not carefully defined, topological paradox may also occur. In raster space, the basic topological concept in vector space—connectedness—is implicitly inherited. This is why the topological properties of spatial entities can also be studied in raster space. Study of entities in raster (discrete) space could be a more efficient method than in vector space, as the expression of spatial entities in discrete space is more explicit than that in connected space.  相似文献   

19.
《Applied Soft Computing》2007,7(1):425-440
Uncertainty management has been considered essential for real world applications, and spatial data and geographic information systems in particular require some means for managing uncertainty and vagueness. Rough sets have been shown to be an effective tool for data mining and uncertainty management in databases. The 9-intersection, region connection calculus (RCC) and egg–yolk methods have proven useful for modeling topological relations in spatial data. In this paper, we apply rough set definitions for topological relationships based on the 9-intersection, RCC and egg–yolk models for objects with broad boundaries. We show that rough sets can be used to express and improve on topological relationships and concepts defined with these models.  相似文献   

20.
目的 模式识别中,通常使用大量标注数据和有效的机器学习算法训练分类器应对不确定性问题。然而,这一过程缺乏知识表征和可解释性。认知心理学和实验心理学的研究表明,人类往往不使用代价如此巨大的机制,而是使用表征、归纳、推理、解释和约束传播等与符号主义人工智能方法类似的手段来应对物体识别中的不确定性并提供可解释性。因此本文旨在从传统的符号计算出发,利用骨架拓扑结构表征提供一种可解释性的思路。方法 以骨架树为基本手段来形成物体拓扑结构特征和几何特征的形式化表征,并基于泛化框架对少量同类表征进行知识抽取来形成关于物体类别的知识概括显式化表征。结果 在形成物体类别的概括表征实验中,通过路径重建直观展示了同类属物体上得到的最一般表征的几何物理意义。在可解释性验证实验中,通过跨数据的拓扑应用展示了新测试样本相对于概括表征的特定差异,表明该表征具有良好的可解释性。最后在形状补全的不确定性推理实验中,不仅可以得到识别结论,而且清晰展示了识别背后做出的判断依据,进一步验证了该表征的可解释性。结论 实验表明一般化的形式表征能够应对尺寸、颜色和形状等不确定性问题,本文方法避免了基于纹理特征所带来的不确定性,适用于任意基于基元的表征方式,具有更好的鲁棒性、普适性和可解释性,计算代价更小。  相似文献   

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