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101.
基于本体的地球空间信息上下文建模   总被引:1,自引:0,他引:1  
总结分析了典型的地球空间信息上下文,基于本体建立了面向地球空间信息服务形式化的上下文信息模型,该模型采用层次化的设计方法,并使用本体描述语言OWL描述上下文,提高了上下文表达能力。最后,设计了一个面向地球空间信息的上下文感知计算模型。  相似文献   
102.
Jurisdictional domains are legal divisions of the Earth’s surface frequently used in classification and search systems for location-based queries. However, there are few compilations of jurisdictional domains that include their evolution. One of the causes is the complexity of their generation. As an advance in this area, this paper describes a process that facilitates the creation of knowledge bases containing the evolution of jurisdictional domains. As application example, this paper presents the creation of a jurisdictional knowledge base of Spain with its evolution between 1830 and 2011.  相似文献   
103.
无线传感器通常用于环境监测,如气候变化、水质和监控灾害管理等。目前,灾害管理是一项十分关键和紧迫的工作,在海啸预警和预测系统方面尤为突出。本文在研制区域水文态势地理信息服务系统(RHSGISS)的基础上,为减缓灾害,研究出了海啸早期预警系统的一种本体式表达。该系统由地震监测台站、海底压力记录仪(BPR)和验潮仪等组成,其主要功用是解释复杂的多维数据。该数据由各种传感器、系统间的互操作性以及处理异构数据等生成。目前的核心问题在于将获取自海啸早期预警系统多个组件的异构数据进行融合以及提供基于Web网络的数据服务。面向特定陆表监测与应急响应任务,本文通过使用开放地理空间联盟(OGC)确定的传感器网络赋能实现(SWE)框架,构建了基于"北斗"卫星导航系统的GPNT服务体系,能为所有接入空天地一体化对地感测网环境下的用户共享互操作性和可伸缩性提供便利。本体因其功能上可以提供明确含义的信息,而成为了解决信息异质性问题的手段。本文在传感器网络数据与数据语义方面提出了一种面向服务的架构(SOA)模型,目的是要提供使用本体和Jena规范来表示更有意义的早期海啸预警系统信息。  相似文献   
104.
This paper presents a new technique for information fusion. Unlike most previous work on information fusion, this paper explores the use of instance‐level (extensional) information within the fusion process. This paper proposes an algorithm that can be used automatically to infer the schema‐level structure necessary for information fusion from instance‐level information. The approach is illustrated using the example of geospatial land‐cover data. The method is then extended to operate under uncertainty, such as in cases where the data are inaccurate or imprecise. The paper describes the implementation of the fusion method within a software prototype. Finally, the paper discusses several key topics for future research, including applications of this work to spatial‐data mining and the semantic web.  相似文献   
105.
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   
106.
Standardization is one of the pillars of interoperability. In this context, efforts promoted by the Open Geospatial Consortium, such as CityGML (Technical University, Berlin), a standard for exchanging three-dimensional models or urban city objects, are welcomed. However, information from other domains of interest (e.g. energy efficiency or building information modeling) is needed for tasks such as land planning, large-scale flooding analysis, or demand/supply energy simulations. CityGML allows extension in order to integrate information from other domains, but the development process is expensive because there is no way to perform it automatically. The discovery of correspondences between CityGML concepts and other domains concepts poses a significant challenge.

Ontology matching is the research field emerged from the Semantic Web to address automatic ontology integration. Using the ontology underlying CityGML and the ontologies which model other domains of interest, ontology matching would be able to find the correspondences that would permit the integration in a more automatic manner than it is done now.

In this paper, we evaluate if ontology matching techniques allow performing an automatic integration of geospatial information modeled from different viewpoints. In order to achieve this, an evaluation methodology was designed, and it was applied to the discovery of relationships between CityGML and ontologies coming from the building information modeling and Geospatial Semantic Web domains. The methodology and the results of the evaluation are presented. The best results have been achieved using string-based techniques, while matching systems give the worst precision and recall. Only in a few cases the values are over 50%, which shows the limitations when these techniques are applied to ontologies with a partial overlap.  相似文献   
107.
基于地理语义的空间关系查询和推理   总被引:3,自引:0,他引:3  
地理空间中的地物,根据其本体类型具有不同的地理语义特征。受到地理语义的影响,人们在描述几何特征和关系相似的物体之间的空间关系时,所用的词汇是不同的。目前,人们在空间关系的自然语言查询方面的研究主要集中在空间关系描述、空间关系自然语言形式化表达、空间关系自然语言查询语句的转换,以及空间关系自然语言查询的查询接口等方面,没有考虑到地理本体的语义差异,这会使得空间关系的自然语言查询不能符合人类语言和认知的习惯。本文依据一些学者在空间关系的自然语言描述的形式化(主要是线和线、线和面等形状的空间地物之间的关系)研究的基础上,针对不同地理本体类型的空间地物和空间关系自然语言描述词汇之间对应的语义关系有所不同的特点,总结了自然语言词汇在描述空间关系时的对应规则,提出不同特征类型地物和描述词汇之间的规则库设计方法,并设计部分空间地物的规则实例。最后,结合空间关系判断函数,设计具体查询系统实践举例证明。  相似文献   
108.
气象灾害本体设计   总被引:3,自引:0,他引:3  
提出了一种基于W3C标准的气象灾害本体化设计思路及其实现方法.在理解中国国家气象灾害预警体系中气象灾害的概念定义、命名规范、等级划分的基础上,提出用阶梯函数表达自然灾害指标,以—阶谓词逻辑的描述逻辑将气象灾害表达为基于气象要素的逻辑判断.随后,气象灾害的逻辑表达被应用于本体化设计中,以此建立起气象灾害分类树、等价公理、对象属性集合和数据属性集合,最终构建得到气象灾害本体知识库.在智能代理的作用下,地面观测气象数据被转化为气象灾害知识.基于本文构建的气象灾害本体知识库已应用于近实时气象灾害GIS分析图的网站发布,可初步实现气象灾害的自动化预警分析.  相似文献   
109.
给出了对ISO19115-3进一步扩展的方案,完善了影像与栅格元数据模型。利用UML概念与OWL概念之间的映射关系,实现了基于OWL表达的影像与栅格元数据规范本体,并利用该本体描述提出了一种基于用户交互的语义扩展方式,并将其应用到目录服务元数据查询中,缩小了用户查询与元数据描述的语义鸿沟,提高了目录服务查询的针对性,并为影像与栅格元数据的发现提供了一种更加人性化的交互方法。  相似文献   
110.
在分析本体技术和交通信息特点的基础上,针对交通概念描述的特殊要求,提出了时空模糊本体的概念,以描述交通领域概念,并利用时空模糊本体进行交通领域知识建模。  相似文献   
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