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《制图学和地理信息科学》2013,40(4):269-283
Many time-critical applications such as emergency response, location-based services, and real time traffic management need instant access to diverse data to make quick decisions and take instantaneous actions. However, two issues block time-critical applications to quickly acquire and integrate spatial data over the web: (1) the heterogeneity of existing GIS systems, and (2) the file-level data sharing systems over the web. This research examines current open standards, protocols, and technologies capable of solving the two issues for real-time spatial data sharing over the web. Focusing on investigating the role of Web Feature Services (WFS) and Web Map Services (WMS), this research has developed a solution for real-time geospatial data sharing at the feature level over the web. A prototype has been implemented to query, extract, create, delete, update, and map geographic features stored in web-accessible OGC (Open Geospatial Consortium) simple feature datastores for transportation emergency applications. The prototype results show that the OGC WFS and WMS play important roles in real-time geospatial data sharing and exchange from heterogeneous sources at the feature level for time-critical applications. The WFS and WMS eliminate time-consuming data translation and facilitate reuse of existing geospatial data over the web. Several issues related to the solution are also discussed in the paper. 相似文献
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Diverse studies have shown that about 80% of all available data are related to a spatial location. Most of these geospatial data are available as structured and semi‐structured datasets, and often use distinct data models, are encoded using ad‐hoc vocabularies, and sometimes are being published in non‐standard formats. Hence, these data are isolated within silos and cannot be shared and integrated across organizations and communities. Spatial Data Infrastructures (SDIs) have emerged and contributed to significantly enhance data discovery and accessibility based on OGC (Open Geospatial Consortium) Web services. However, finding, accessing, and using data disseminated through SDIs are still difficult for non‐expert users. Overcoming the current geospatial data challenges involves adopting the best practices to expose, share, and integrate data on the Web, that is, Linked Data. In this article, we have developed a framework for generating, enriching, and exploiting geospatial Linked Data from multiple and heterogeneous geospatial data sources. This proposal allows connecting two interoperability universes (SDIs, more specifically Web Feature Services, WFS, and Semantic Web technologies), which is evaluated through a study case in the (geo)biodiversity domain. 相似文献
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《International Journal of Digital Earth》2013,6(3):175-193
The hypermap concept was introduced in 1992 as a way to hyperlink geospatial features to text, multimedia or other geospatial features. Since then, the concept has been used in several applications, although it has been found to have some limitations. On the other hand, Spatial Data Infrastructures (SDIs) adopt diverse and heterogeneous service oriented architectures (SOAs). They are developed by different standard bodies and are generally disconnected from mass market web solutions. This work expands the hypermap concept to overcome its limitations and harmonise it with geospatial resource oriented architecture (ROA), connecting it to the semantic web and generalising it to the World Wide Hypermap (WWH) as a tool for building a single ‘Digital Earth’. Global identifiers, dynamic links, link purposes and resource management capabilities are introduced as a solution that orchestrates data, metadata and data access services in a homogeneous way. This is achieved by providing a set of rules using the current Internet paradigm formalised in the REpresentational State Transfer (REST) architecture and combining it with existing Open Geospatial Consortium (OGC) and International Organization for Standardization (ISO) standards. A reference implementation is also presented and the strategies needed to implement the WWH, which mainly consist in a set of additions to current Geographic Information System (GIS) products and a RESTful server that mediates between the Internet and the local GIS applications. 相似文献
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A regional groundwater management system has been elaborated, integrating Relational Database Management System (RDBMS) and various web services. It consists of web geospatial application so-called HydrIS (Hydrogeological Information System) based on Open Source components and technologies, leading to a feasible and low-cost solution. Therefore, HydrIS permits delivery of data from a number of heterogeneous sources to standards supported by the Open Geospatial Consortium (OGC). The protocols used for exchanging data are also derived from OGC standards, i.e., WMS (Web Mapping Service), WFS (Web Feature Service), and WCS (Web Coverage Service). Finally, a geoportal was developed, which consists of client-applications that communicate with different Web Services (WMS, WCS, and WFS) through http-requests. 相似文献
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当前云计算的发展已能支持高性能的地理空间服务,比如在数字城市和电子商务等行业。Apache基金支持下的开源软件框架Hadoop,可以用来构建一个云环境的集群用来存储和处理高性能的地理空间数据。开放地理空间联盟(OGC)的Web三维服务(W3DS)就是这样一个很好的三维的地理空间数据服务标准。在标准的云计算环境下将是一个更好的应用示范。基于此,本文研究了OGC的W3DS服务在云计算环境下的实验结果。实验采用Apache的Hadoop框架作为三维地理空间信息服务实验展示的基础。实验结果对展示高性能的三维地理空间信息提供了有价值的参考。 相似文献
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HydrIS:一个用于地下水管理的开放的GIS决策支持系统——以Morocco为例(英文) 总被引：1，自引：0，他引：1
A regional groundwater management system has been elaborated, integrating Relational Database Management System (RDBMS) and
various web services. It consists of web geospatial application so-called HydrIS ( Hydrogeological Information System) based
on Open Source components and technologies, leading to a feasible and low-cost solution. Therefore, HydrIS permits delivery
of data from a number of heterogeneous sources to standards supported by the Open Geospatial Consortium (OGC). The protocols
used for exchanging data are also derived from OGC standards, i.e., WMS (Web Mapping Service), WFS (Web Feature Service),
and WCS (Web Coverage Service). Finally, a geoportal was developed, which consists of client-applications that communicate
with different Web Services (WMS, WCS, and WFS) through http-requests.
A prototype for web-based GIS application was designed using the deegree Framework to provide systematic interfaces and functions.
This system was developed to demonstrate the value of making hydrogeological data more widely accessible through client/server
architecture. This experience and knowledge already gained in this project will be a source for technology transfer and policy
decisions. Otherwise, this will enable user groups to improve the management of their groundwater resources and contribute
to enhanced decision support capabilities.
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GeoPW: Laying Blocks for the Geospatial Processing Web 总被引：2，自引：0，他引：2
Peng Yue Jianya Gong Liping Di Jie Yuan Lizhi Sun Ziheng Sun Qian Wang 《Transactions in GIS》2010,14(6):755-772
Recent advances in Web‐related technologies have significantly promoted the wide sharing and integrated analysis of distributed geospatial data. Geospatial applications often involve diverse sources of data and complex geoprocessing functions. Existing Web‐based GIS focuses more on access to distributed geospatial data. In scientific problem solving, the ability to carry out geospatial analysis is essential to geoscientific discovery. This article presents the design and implementation of GeoPW, a set of services providing geoprocessing functions over the Web. The concept of the Geospatial Processing Web is discussed to address the geoprocessing demands in the emerging information infrastructure, and the role of GeoPW in establishing the Geospatial Processing Web is identified. The services in GeoPW are implemented by developing middleware that wraps legacy GIS analysis components to provide a large number of geoprocessing utilities over the Web. These services are open and accessible to the public, and they support integrated geoprocessing on the Web. 相似文献
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Chuanrong Zhang Tian Zhao Weidong Li 《International Journal of Applied Earth Observation and Geoinformation》2010
Although the fast development of OGC (Open Geospatial Consortium) WFS (Web Feature Service) technologies has undoubtedly improved the sharing and synchronization of feature-level geospatial information across diverse resources, literature shows that there are still apparent limitations in the current implementation of OGC WFSs. Currently, the implementation of OGC WFSs only emphasizes syntactic data interoperability via standard interfaces and cannot resolve semantic heterogeneity problems in geospatial data sharing. To help emergency responders and disaster managers find new ways of efficiently searching for needed geospatial information at the feature level, this paper aims to propose a framework for automatic search of geospatial features using Geospatial Semantic Web technologies and natural language interfaces. We focus on two major tasks: (1) intelligent geospatial feature retrieval using Geospatial Semantic Web technologies; (2) a natural language interface to a geospatial knowledge base and web feature services over the Semantic Web. Based on the proposed framework we implemented a prototype. Results show that it is practical to directly discover desirable geospatial features from multiple semantically heterogeneous sources using Geospatial Semantic Web technologies and natural language interfaces. 相似文献
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A Sensor Web registry acts as a broker in a service‐oriented environment to publish and discover Sensor Web resources (e.g. sensors, sensor services, observations, and alerts). The Catalogue Service for the Web (CSW) developed by the Open Geospatial Consortium (OGC) defines a standard interface and protocol for publishing and discovering geospatial resources. This article adopts the CSW for the development of a Sensor Web registry. Metadata for Sensor Web resources are registered into the catalogue information model – the ebXML Registry Information Model (ebRIM). In the Sensor Web environment, sensor observations can be available in real‐time or near‐real‐time, and thus metadata registered in CSW need to be updated frequently. This article proposes an incremental harvesting approach, which can harvest the updated metadata efficiently. A prototypical implementation is provided to demonstrate the applicability of the approach. 相似文献
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OGC与我国地理信息产业 总被引：7，自引：0，他引：7
通过对开放地理信息系统联合会(OGC)的现有规范介绍，探讨了OGC规范与地理空间数据、服务互操作性的关系，以及对我国地理信息产业发展的意义。 相似文献
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网络地图服务(WMS)是基于开放地理信息系统协会(OGC)规范的在线地图服务,通过WMS可以实现多源异构地理空间数据的转换和封装,Internet上现在发布了越来越多的WMS服务。本文研究WMS网络地图服务的查找方法和组合使用的方法,用户通过组合网络WMS服务和自定义服务既可满足应用需求,又可达到快速开发应用的目的。 相似文献
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《International Journal of Digital Earth》2013,6(6):449-470
Finding the right spatially aware web service in a heterogeneous distributed environment using criteria such as service type, version, time, space, and scale has become a challenge in the integration of geospatial information services. A new method for retrieving Open Geospatial Consortium (OGC) Web Service (OWS) that deals with this challenge using page crawling, link detection, service capability matching, and ontology reasoning, is described in this paper. Its major components are distributed OWS, the OWS search engine, the OWS ontology generator, the ontology-based OWS catalog service, and the ontology-based multi-protocol OWS client. Experimental results show that the execution time of this proposed method equals only 0.26 of that of Nutch's method. In addition, the precision is much higher. Moreover, this proposed method can carry out complex OWS reasoning-based queries. It is being used successfully for the Antarctica multi-protocol OWS portal of the Geo-Information Web Service Portal of the Polar. 相似文献
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OGC(OpenGISConsortium)组织所提出的空间信息服务框架中包含多种需要消耗大量计算资源的计算密集型服务,如海量空间信息的存储与获取服务、影像处理服务等,但该组织并未对这类服务的具体实现方式及技术作出规定和说明。针对这类计算密集型空间信息服务,文章从技术层面研究了基于PC集群并行计算环境的计算密集型空间信息服务的实现方法及技术架构,为研究开发高性能的空间信息服务进行了探索。 相似文献
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The emergence of the Sensor Web has paved the way for a new set of innovative software applications that exploit the enhanced availability of real‐time information. This article describes one such application built from Sensor Web components that aggregates GPS track data from a fleet of vehicles to provide an overview of road traffic congestion at the city scale. The application embodies a Service Oriented Architecture; web service components are used to archive and pre‐process incoming sensor observations, to encapsulate a horizontally partitioned spatial database that performs geoprocessing, and to disseminate results to client applications. Our results confirm that floating car data can provide an accurate depiction of current road traffic conditions. The presented solution uses Open Geospatial Consortium web services where possible and serves to highlight the difficulties inherent in achieving horizontal database scalability in sensor based geoprocessing systems. 相似文献