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1.
The paper compares hydrographic and terrain categories in the geospatial data standards of the United States, Taiwan, and Russian Federation where the dominant languages used are from different language families. It aims to identify structural and semantic differences between similar categories across three geospatial data standards. By formalizing the data standard structures and identifying the properties that differentiate sibling categories in each geospatial data standard using well-known formal relations and quality universals, we develop a common basis on which hydrographic and terrain categories in the three data standards can be compared. The result suggests that all the three data standards structure categories with a mixture of relations even though most of them are well-known relations in top-level ontologies. Similar categories can be found across all the three standards. Cases of categories from different standards carrying identical meaning are rare. Partial overlaps in the meaning of the similar categories can be a direct result of different quality universals at work in defining and distinguishing these categories, or in the case of these categories being ordered by size, the threshold values for distinguishing the categories are ambiguous and language-dependent. Understanding these differences avoids incorrect mappings of categories in multilingual applications. More importantly, it provides a starting point for more effective mapping between hydrographic and terrain categories between English, Mandarin, and Russian.  相似文献   

2.
Abstract

In state-of-the-art GIS, geographical features are represented as geometric objects with associated topological relations and classification attributes. Semantic relations and intrinsic interrelations of the features themselves are generally neglected. In this paper, a feature-based model that enhances the representation of geographical features is described. Features, as the fundamental depiction of geographical phenomena, encompass both real world entities and digital representation. A feature-based object incorporates both topological relations among geometric elements and non-topological (semantic) relations among features. The development of an object-oriented prototype feature-based GIS that supports relations between feature attributes and feature classes is described. Object-oriented concepts such as class inheritance and polymorphism facilitate the development of feature-based GTS.  相似文献   

3.
There has been significant progress transforming semi-structured data about places into knowledge graphs that can be used in a wide variety of geographic information systems such as digital gazetteers or geographic information retrieval systems. For instance, in addition to information about events, actors, and objects, DBpedia contains data about hundreds of thousands of places from Wikipedia and publishes it as Linked Data. Repositories that store data about places are among the most interlinked hubs on the Linked Data cloud. However, most content about places resides in unstructured natural language text, and therefore it is not captured in these knowledge graphs. Instead, place representations are limited to facts such as their population counts, geographic locations, and relations to other entities, for example, headquarters of companies or historical figures. In this paper, we present a novel method to enrich the information stored about places in knowledge graphs using thematic signatures that are derived from unstructured text through the process of topic modeling. As proof of concept, we demonstrate that this enables the automatic categorization of articles into place types defined in the DBpedia ontology (e.g., mountain) and also provides a mechanism to infer relationships between place types that are not captured in existing ontologies. This method can also be used to uncover miscategorized places, which is a common problem arising from the automatic lifting of unstructured and semi-structured data.  相似文献   

4.
In this article we show that the Voronoi-based nine-intersection (V9I) model proposed by Chen et al. (2001, A Voronoi-based 9-intersection model for spatial relations. International Journal of Geographical Information Science, 15 (3), 201–220) is more expressive than what has been believed before. Given any two spatial entities A and B, the V9I relation between A and B is represented as a 3 × 3 Boolean matrix. For each pair of types of spatial entities that is, points, lines, and regions, we first show that most Boolean matrices do not represent a V9I relation by using topological constraints and the definition of Voronoi regions. Then, we provide illustrations for all the remaining matrices. This guarantees that our method is sound and complete. In particular, we show that there are 18 V9I relations between two areas with connected interior, while there are only nine four-intersection relations. Our investigations also show that, unlike many other spatial relation models, V9I relations are context or shape sensitive. That is, the existence of other entities or the shape of the entities may affect the validity of certain relations.  相似文献   

5.
This article explores the notion of a system of ontologies specifically designed for the needs of an information science. A framework for geographic information ontologies is outlined that focuses on geographic information constructs rather than on the direct representation of real-world entities or on linguistic terms. The framework takes the form of a generative hierarchy anchored by the notion of intentionality at one end and of a spatiotemporal field of potentially relevant information at the other. Two theoretical notions are used in the generation of the hierarchy. The first is the principle of semantic contraction, whereby, starting from a level of geographic information constructs specified so as to reflect user intentionality, semantically coherent domains of properties are removed over several steps until only the rudiments of a spatiotemporal information system are left. The second notion is that of object of discourse, which allows entities to be represented as the composites of geographic information constructs at the higher levels of the hierarchy, explicitly reflecting the connections between the purpose, function, appropriate internal constitution, and ensuing categorization of the entities represented. The framework's main contribution is thus twofold: first, it allows the notions of user purpose and object function to be directly built into geographic representations; second, it proposes a hierarchy of ontological levels that are linked by systematic semantic relations. Further, the framework presents an integrated view of object and field representations. It may also provide a novel perspective on a number of issues of ongoing interest in geographic information science.  相似文献   

6.
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   

7.
蔡晓梅  曹婧  刘俊 《地理学报》2022,77(10):2633-2649
在法国“五月风潮”和后现代主义思潮的影响下,拼装理论应运而生。该理论提出了以根茎思维为基础的动态生成哲学观,批判地揭露了现有研究以网络结构为主,忽视空间拓扑的局限,为人文地理学开辟了新的知识空间。一方面,拼装理论在“空间生产理论”“异托邦”和“第三空间”等空间理论的基础上形成“异质生成空间”,强调属性不同的元素互动的同时,更关注时空不断生成、变化的逻辑;另一方面,拼装理论重构了关系,强调“客体的能动性”和“外部联系”,生成“后关系本体论”,承认所有事物都是通过关系进行拼装的。随着拼装理论在人文地理领域的运用,现有的实证研究主要聚焦于政治拼装与流动性、城市拼装与批判城市化、日常生活拼装与非人的能动性,以及与行动者网络理论、复杂性理论的比较研究。为了阐述拼装理论的内涵,增强理论的应用性,本文以案例的形式详细解析了边界拼装蕴含的拼装逻辑。此外,基于拼装理论为人文地理学注入的过程逻辑与克服人类中心主义的理念,以及该理论特征与中国社会转型期的耦合性,期望国内地理学者能批判地运用拼装理论解释中国情境,以便推动中国人文地理学理论与哲学方法论的多元发展。  相似文献   

8.
基于Voronoi模型的海南岛旅游资源集合体空间边界提取   总被引：1，自引：0，他引：1  
旅游资源是旅游业发展的物质条件,是开展各项旅游活动的载体和基础。旅游资源分类方法和评价理论研究已取得了较大的进展,但在旅游资源调查与规划实践中,以有研究通常将一个景区或大规模地理实体与小规模实体在同一个标准下衡量与对比,未考虑旅游资源的地理空间尺度特征。不同尺度的旅游地域空间,旅游资源评价、规划方法及其开发方向都不同。本文目的是通过梳理不同尺度旅游资源空间单元概念,对最难界定的集合体进行空间识别。基于集合体的概念认知,利用空间语义关系构建本体概念模型,提出了不同类型旅游资源集合体的空间边界提取方法。鉴于此,以海南岛为例进行实证研究,运用空间语义关系构建3种不同类型的旅游资源本体概念模型,在此基础上对不同类型旅游资源集合体进行条件约束判断,并利用泰森多边形与缓冲区分析方法对其进行空间识别。与规划范围结果对比发现,该方法可较好地近似表达旅游资源集合体空间边界及空间关系。每种类型的集合体空间语义关系存在树状层次结构,包含2个层次,空间形态呈多边形和带状分布。研究方法具有可操作性,能够为旅游规划与管理提供科学参考。  相似文献   

9.
《The Journal of geography》2012,111(4):220-223
Abstract

This article identifies teaching strategies to explore cultural universals. Traits that contribute to distinguishing one culture from another can be classified into general categories that all cultures share. Students identify universals in their daily lives and then compare and contrast different cultural perspectives through an exploration of these universals. Computer technology provides access to images and information about other cultures that might be used to increase students' understanding of cultural perspectives. The Internet provides a vehicle for classrooms to exchange cooperative creative writing stories that allow students the opportunity to explore different cultural perspectives through the eyes of other students around the world. Suggestions about how to establish and conduct a classroom exchange project over the Internet are provided.  相似文献   

10.
Prominent in many historical accounts of European first contact with Australian nature are stories of encounters between European curiosity and curious Australian biota, such as the platypus and the eucalyptus. In this paper, I argue that post-settlement relations with the Goulburn River, one of the largest rivers in south-east Australia, likewise attest to the centrality of curiosity in early European engagements with Australian landscape. In mapping several relational ontologies of the Goulburn River, I attend to the socio-material practices in which this river has been performed as different and as normal. My interest is in a specific form of difference, that of antipodean difference: the river as topsy-turvy, backwards, unusual, or inverted in relation to some presumed norm, whether that norm be rooted in memories and experiences of European rivers or imaginings of an original state of nature. This is a story of how an extraordinary river became ordinary, and of how we might understand antipodean difference as curious in deed (i.e. as performed), rather than as curious indeed (i.e. as an innate quality of Australian nature).  相似文献   

11.
When separation between geospatial features is desired, an obstacle or barrier is used to maintain distance between the features. Barriers are used in a wide variety of domains, such as hazards, transportation, and public safety. Floodwalls, for example, prevent flooding rivers or lakes from inundating buildings. This work presents an ontology design pattern for barriers and barring events useful for GIS. In this ontology design pattern, active features (e.g., the water-body that is causing flooding) and target features (e.g., buildings requiring flood protection) are defined. Along with these key features, the ontology design pattern also captures certain barring events. These are the dynamics that arise from the placement of barriers and include Blocking, Enclosing, KeepingIn and KeepingOut, involving interactions among barriers, and active and target features. The set of classes that model these features and events as well as the relations between them are presented and formalized. This design pattern is ready for integration in a GIS to allow queries on barriers and barring events that do not currently have explicit support in most GIS.  相似文献   

12.
ABSTRACT

Defining and identifying duplicate records in a dataset is a challenging task which grows more complex when the modeled entities themselves are hard to delineate. In the geospatial domain, it may not be clear where a mountain, stream, or valley ends and begins, a problem carried over when such entities are catalogued in gazetteers. In this paper, we take two gazetteers, GeoNames and SwissNames3D, and perform matching – identifying records in each that are about the same entity – across a sample of natural feature records. We first perform rule-based matching, establishing competitive results, then apply machine learning using Random Forests, a method well-suited to the matching task. We report on the performance of a wider array of matching features than has been previously studied, including domain-specific ones such as feature type, land cover class, and elevation. Our results show an increase in performance using machine learning over rules, with a notable performance gain from considering feature types, but negligible gains from other specialized matching features. We argue that future work in this area should strive to be more reproducible and report results on a realistic testing pipeline including candidate selection, feature extraction, and classification.  相似文献   

13.
通过认知实验,探讨出行者倾向于选择环路的影响因子。以北京市三环路为主要研究对象,按照12方向城市坐标框架和三环路路段的现实名称划分特点提出九宫格模式。以两点和封闭曲线的拓扑关系为标准,从道路起点、终点和九宫格的拓扑关系中选出18种典型情况进行分析。测试及统计分析实验结果显示,路径起点和终点、冗余路段比重、路径方向影响出行者对环路的选择。  相似文献   

14.
谢富胜  巩潇然 《地理学报》2018,73(8):1407-1420
尼尔·史密斯是世界知名的人文地理学者和马克思主义地理学家。他在不平衡发展理论的基础上,整合马克思主义和地理学的资本周期运动、空间一体化与尺度推移等范畴,提出了实现平衡发展的途径,极大地丰富和发展了马克思主义地理学,为研究当代社会空间问题提供了更为具体的分析框架和新的理论解释。其理论的核心是把地理空间视为生产资料、社会产物以及空间关系的总和,认为地理空间生产是特定时期资本增殖的重要方式。目前中国学者虽引进其部分理论,但整体了解还比较欠缺。本文将其理论概括和梳理为空间生产、地理尺度、美式帝国主义、绅士化4个方面,分析资本积累驱动下地理空间的不平衡发展过程,深度解析社会、空间与地理的尺度交错与互动关系,阐明资本周期运动、美式帝国扩张和绅士化的逻辑关联,最后以租隙理论为主剖析了城市尺度的资本周期运动。本文旨在为国内学者研究史密斯的马克思主义空间理论以及马克思主义地理学提供纲要和逻辑线索,并为中国城市化转型和经济增长方式转变提供理论参考和方法启示。  相似文献   

15.
Although 97% of U.S. farms are “family-owned,” little research examines how gender and sexual relationships – inherent in familial dynamics – influence farmers’ practices and livelihoods. Gender and sexual dynamics – shaped by race and class – affect who is considered a farmer, land management decisions, and access to resources like land, subsidies, and knowledge. We use feminist and queer lenses to illuminate how today’s agricultural gender and sexual relations are not “natural,” but when left uninterrogated are constructed in ways that harm women and queer farmers while limiting potential to develop sustainable practices. Women and queer farmers also resist, “re-orienting” gender and sexual relations in ways that expand possibilities for achieving food justice and ecological sustainability. We offer “relational agriculture” as a tool for making visible and re-orienting gender and sexual relations on farms. Relational agriculture brings sexuality into food justice and demonstrates the centrality of gender and sexuality to agricultural sustainability.  相似文献   

16.
多粒度时空对象数据模型更注重现实世界复杂、动态现象的表达,能更好地应用于智能设施管理和智能决策支持系统。该文基于多粒度时空对象数据模型及其建模理论,对高速公路智能监控系统中实体对象的特征和关系进行概念建模,设计数据存储方案,开发高速公路智能监控多粒度时空对象建模原型系统,并验证数据模型的实用性。结果表明:多粒度时空对象数据模型可以很好地支撑高速公路智能监控系统中动态智能实体及实体间复杂关系的表达、管理和分析,实现对路情的智能分析与决策。  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.
This article presents a geometric algebra-based model for topological relation computation. This computational model is composed of three major components: the Grassmann structure preserving hierarchical multivector-tree representation (MVTree), multidimensional unified operators for intersection relation computation, and the judgement rules for assembling the intersections into topological relations. With this model, the intersection relations between the different dimensional objects (nodes at different levels) are computed using the Tree Meet operator. The meet operation between two arbitrary objects is accomplished by transforming the computation into the meet product between each pair of MVTree nodes, which produces a series of intersection relations in the form of MVTree. This intersection tree is then processed through a set of judgement rules to determine the topological relations between two objects in the hierarchy. Case studies of topological relations between two triangles in 3D space are employed to illustrate the model. The results show that with the new model, the topological relations can be computed in a simple way without referring to dimension. This dimensionless way of computing topological relations from geographic data is significant given the increased dimensionality of geographic information in the digital era.  相似文献   

19.
两极是世界各国关注和研究的热点地区,极地科学数据量飞速增长,如何高效地管理极地科学数据并提供数据的智能服务,已成为极地数据库研究的重点。针对目前以关键词和主题词等字符匹配为核心的数据库查询中存在的查不全、查不准等问题,以中国南北极数据中心的元数据库作为数据源,引入本体论思想,提出了考虑空间关系的极地科学数据本体构建方法,研究了极地科学数据的语义概念、属性及语义关系,着重考虑了空间关系在本体构建中的形式化表示模型;设计了考虑空间关系的极地本体总体框架;最后,利用本体构建工具实现了极地科学数据本体库的搭建。考虑空间关系的极地科学数据本体库的建立对极地科学数据的精确发现和信息共享提供了有力的支撑。  相似文献   

20.
热带气旋降水模拟研究进展   总被引：1，自引：1，他引：0  
中国是遭受热带气旋灾害最为严重的国家之一,准确的降水模拟对于开展热带气旋灾害风险评估有重要意义。本文从热带气旋灾害风险评估的视角,将降水模拟分为基于极值理论的降水极值模拟、基于站点的降水时空模拟和基于热带气旋路径的降水事件模拟3大类;根据风险评估对降水模拟的需求,从模型构建、发展及其特点等方面对3类模型进行分析评述;进而提出面向风险评估的热带气旋降水模拟,应兼顾降水模拟的一般性和热带气旋暴雨模拟的特殊性,平衡处理降水模拟结果的准确性、统计量的可靠性和计算量问题。以极值理论对降水极值模拟为基础,充分发挥降水时空模拟在处理长时间降水序列中的优势,并加强热带气旋降水的理论研究,进一步完善热带气旋降水事件的模拟模型。  相似文献   

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