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Miriam Baglioni Emiliano Giovannetti Maria Vittoria Masserotti Chiara Renso Laura Spinsanti 《Transactions in GIS》2008,12(Z1):31-44
Querying geographical information systems has been recognized as a difficult task for non‐expert users. Furthermore, user queries are often characterized by semantic aspects not directly managed by traditional spatial databases or GIS. Examples of such semantic geospatial queries are the use of implicit spatial relations between objects, or the reference of domain concepts not explicitly represented in data. To handle such queries, we envisage a system that translates natural language queries into spatial SQL statements on a database, thus improving standard GIS with new semantic capabilities. Within this general objective, the contribution of this article is to introduce a methodology to handle semantic geospatial queries issued over a spatial database. This approach captures semantics from an ontology built upon the spatial database and enriched by domain concepts and properties specifically defined to represent the localization of objects. Some examples of the use of the methodology in the urban domain are presented. 相似文献
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《制图学和地理信息科学》2013,40(4):291-299
Nautical information is one example of spatial data with a strong temporal component. This paper describes the methods of temporal data representation to be used in a National Ocean Service (NOS) Automated Nautical Charting System (ANCS II). The system will be capable of tracing spatial change over time and of tracking cartographic and data-base procedures within the agency. The discussion describes a method of spatiotemporal representation within traditional geographic information systems (GIS) data structures, draws a distinction between information-oriented and production-oriented temporality, and identifies three fundamental elements of temporal metadata. 相似文献
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RS与GIS一体化数据结构的研究 总被引：1，自引：0，他引：1
详细阐述了RS与GIS一体化的概念 ,通过对RS与GIS一体化方面的研究与分析 ,进一步明确RS与GIS一体化对空间数据存储结构的要求 ,着重探讨了几种典型的用于RS与GIS一体化的数据结构 ,针对现有数据结构存在的问题与不足 ,提出了一种具有普遍适用价值的基于语义网络的空间数据存储结构 ,并给出一个应用实例 相似文献
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GIS空间分析模型的建立 总被引：5，自引：0，他引：5
GIS的发展已有了30年的历史,在此期间人们的注意力多集中于空间数据结构及计算机制图方面,有关空间分析的问题尚不突出,但在今天,对于空间数据结构的研究已相对成熟,计算机制产了达到了实用化水平,实用的软件以及实际的系统均有计多成功的实例,因此系统的空间的空间分析功能就成为人们倍加关注的热点,可以认为,GIS的发展已从数据库型GIS进入分析型GIS的阶段。本文正是基于此,对空间分析的方法作了理论上的探讨,提出了按处理对象（图像,数据,事件）的不同来相应开发GIS软件的通用型,专用型空间分析模型,并分别采取“内嵌”或“外挂”的途径予以结合。最后以电力GIS中不同空间分析模型不同的建立方法为例,说明此咱分类方法可有效的解决时间,资金与人力资源的矛盾,具有很高的实用价值。 相似文献
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应用Arc/Info建立湖北省区域稳定性评价空间数据库 总被引：1，自引：0，他引：1
以Arc/Info为基本工具,以遥感信息为获取、更新数据库数据的主要信息源,结合前人地学资料,建立了湖北省区域稳定性评价空间数据库,阐述了该空间数据库的内容、功能、应用和意义. 相似文献
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关于线状地理特征空间关系的自然语言描述的形式化表达 总被引：1，自引：0，他引：1
目前的地理信息系统都使用定量的方法存储和查询空间信息,不能反映人们的定性思维方式,因此它表达地理空间信息的能力受到限制。在关于空间关系的自然语言描述的调查的基础上,本文定义了一组能反映线状物体空间关系的度量指标,结合反映拓扑关系的定量指标,使用决策树的数据挖掘算法,对调查结果进行分析,形式化了描述空间关系的自然语言词汇,建立了模糊的自然语言表达和图形的几何特征之间的联系。自然语言形式化后得到的规则可用于空间关系的自然语言查询系统。 相似文献
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YU Nenghai WANG Xiaogang LIU Zhengkai ZHANG Rong 《地球空间信息科学学报》2001,4(3):21-28
1 ＴｈｅｃｏｎｃｅｐｔｏｆｔｈｅｉｎｔｅｇｒａｔｉｏｎｏｆＲＳｗｉｔｈＧＩＳＴｈｅｉｎｔｅｇｒａｔｉｏｎｏｆｒｅｍｏｔｅｓｅｎｓｉｎｇ (ＲＳ)ｗｉｔｈｇｅｏ ｇｒａｐｈｉｃａｌｉｎｆｏｒｍａｔｉｏｎｓｙｓｔｅｍ (ＧＩＳ)ｉｓａｈｏｔｓｐｏｔｉｎｇｅｏｇｒａｐｈｉｃａｌｉｎｆｏｒｍａｔｉｏｎｓｃｉｅｎｃｅ .ＴｈｅｃｏｎｃｅｐｔｏｆｔｈｅｉｎｔｅｇｒａｔｉｏｎｏｆＲＳｗｉｔｈＧＩＳ ,ｉｎｔｈｅｖｉｅｗｏｆＰｒｏｆ.ＬｉＤｅｒｅｎ ,ｉｓｔｈａｔＲＳｉｓｔｈｅｗａｙｔｏｏｂｔａｉｎｔｈｅｉｎｆｏｒｍａ ｔｉ… 相似文献
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The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science. A good database structure is important to the integration of RS with GIS, which should be beneficial to the complete integration of RS with GIS, able to deal with the disagreement between the resolution of remote sensing images and the precision of GIS data, and also helpful to the knowledge discovery and exploitation. In this paper, the database structure storing the spatial data based on semantic network is presented. This database structure has several advantages. Firstly, the spatial data is stored as raster data with space index, so the image processing can be done directly on the GIS data that is stored hierarchically according to the distinguishing precision. Secondly, the simple objects are aggregated into complex ones. Thirdly, because we use the indexing tree to depict the relationship of aggregation and the indexing pictures expressed by 2-D strings to describe the topology structure of the objects, the concepts of surrounding and region are expressed clearly and the semantic content of the landscape can be illustrated well. All the factors that affect the recognition of the objects are depicted in the factor space, which provides a uniform mathematical frame for the fusion of the semantic and non-semantic information. Lastly, the object node, knowledge node and the indexing node are integrated into one node. This feature enhances the ability of system in knowledge expressing, intelligent inference and association. The application shows that this database structure can benefit the interpretation of remote sensing image with the information of GIS. 相似文献
9.
Kimfung Liu Wenzhong Shi 《International Journal of Applied Earth Observation and Geoinformation》2009
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
10.
数据模型是描述数据内容及其相互关系的工具，它是数据库设计的核心问题之一。空间数据相对于一般事务性数据具有数据量大和更加复杂的特点，因此，地理信息系统（ＧＩＳ）中空间数据模型的研究显得尤为重要。商业化的ＧＩＳ一般采用关系数据模型，而关系数据模型缺乏表达空间实体及其相互关系的能力，因此形成了图形库与属性库相分离的ＧＩＳ系统结构。这种结构不便于空间实体的整体管理。为解决这一问题，人们探索了扩展的关系模型和面向对象的数据模型。本文介绍了这三种ＧＩＳ数据模型及其与之对应的三种系统结构，分析了这些模型与系统结构的优越性和不足之处，并揭示了数据模型与系统结构之间的内在关系。 相似文献
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GIS空间目标的广义Hausdorff距离模型 总被引：4，自引：0，他引：4
分析了GIS中常用的空间距离度量及其存在的问题，这些距离度量没有顾及空间目标的整体形状、位置分布等特征。基于此，引入了Hausdorff距离的概念，给出了Hausdorff距离的计算方法，分析指出了Hausdorff距离容易受空间目标局部几何形状的影响。进而从统计学的角度分析了现有的距离度量并不能有效地表达空间目标间距离的整体分布，并提出了一种广义Hausdorff距离模型，这种距离模型能够度量空间目标间距离分布的中心趋势和离散度。实际算例证明了此模型在GIS环境下的实现方法。 相似文献
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Spatial object and spatial relationship are two basic concepts of GIS.Spatial object is the digital representation of geographical entity or phenomenon,which forms the basis for data management and analysis;spatial relationship is theconnexion between spatial objects when geometric properties are considered.Thecommonly used classification of spatial objects as points,lines and areas is mathe-matically strict,and suitable for data management,but a bit too generalized forrepresenting real entities and extracting spatial relationships.A good classificationmodel should not only be good for representing real entities,but also good for re-vealing spatial relationships,therefore good for formalizing spatial analyses. 相似文献
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面向交通地理信息时空特征描述的Spatial-UML研究 总被引：1，自引：1，他引：0
空间信息系统建模的多样性、主流信息技术的高度集成性以及逐渐变复杂的系统体系都使得软件和数据库设计者向可视化建模的主流方向发展。分析面向地理信息时空特征描述而建立的空间可视化语言插件(SpatialPVLs),并基于可视化建模技术标准,应用统一建模语言(UML)内置的扩展机制实现了针对地理信息时空特征描述的扩展。UML和SpatialPVLs的集成过程定义了面向地理信息时空特征描述的可视化建模语言,即Spatial-UML。最后,以城市交通模拟地理信息系统(GIS)数据概念模型设计为实例,验证Spatial-UML的适用性和扩展性,建立一个可以满足不同领域用户访问和理解的互协作建模架构,实现交通地理对象的空间、时态和时空特征的可视化标准描述和表达。 相似文献
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Development of a GIS data model with spatial, temporal and attribute components based on object-oriented approach 总被引：1，自引：0，他引：1
SHI Wenzhong ZHANG Minwen 《地球空间信息科学学报》2000,3(1):17-23
1 lntroductionA Mraphical object normal1y poSSeSSes threecomPOnents: spatiaI, temporal and attribute asPeCts.The first comPOnent describes the spatial extent ofan object, such as the boundary of a Iand parcel.The second describes timesrelated information, fOrinstance, the beginning and end time of a land Par-cel. The third describes the attribute characteristicsof obects, fOr example, the type of land cover.These three comPOnents constitute a complete im-age of an object.In most of the… 相似文献
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This paper presents a conceptual data model, the STA-model, for handling spatial, temporal and attribute aspects of objects in GIS. The model is developed on the basis of object-oriented modeling approach. This model includes two major parts: (a) modeling the signal objects by STA-object elements, and (b) modeling relationships between STA-objects. As an example, the STA-model is applied for modeling land cover change data with spatial, temporal and attribute components. 相似文献
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DINGHong GUOQingsheng DUXiaochu 《地球空间信息科学学报》2004,7(3):225-230
Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similarity among spatial directions. One is to measure the similarity among spatial directions based on the features of raster data and the changes of distances between spatial objects, the other is to measure the similarity among spatial directions according to the variation of each raster cell centroid angle. The two methods overcome the complexity of measuring similarity among spatial directions with direction matrix model and solve the limitation of small changes in direction. The two methods are simple and have broader applicability. 相似文献
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Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similarity among spatial directions. One is to measure the similarity among spatial directions based on the features of raster data and the changes of distances between spatial objects, the other is to measure the similarity among spatial directions according to the variation of each raster cell centroid angle. The two methods overcome the complexity of measuring similarity among spatial directions with direction matrix model and solve the limitation of small changes in direction. The two methods are simple and have broader applicability. 相似文献