首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
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   

2.
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   

3.
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.   相似文献   

4.
Spatial Data Infrastructures (SDI) have been widely accepted to exchange geospatial data among organizations. Today SDIs main focus lies on the provision of geospatial data in the form of distributed spatial web services, the retrieval through catalogues, and visualization in the form of Web Map Services (WMS). The hypothesis presented in this paper takes SDI's one step further by providing a method to process geodata in an Open Geospatial Consortium (OGC) compliant way into information. Two case studies present the potential of standardized geoprocessing services. In addition, this paper addresses the problem of service chaining by providing a system architecture to implement complex geoprocessing models and workflows based on web services using Web Service Orchestration (WSO). The proposed methods utilize spatial standards provided by OGC, the International Organization for Standardization (ISO) and ‘mainstream IT’ standards provided by the World Wide Web Consortium (W3C) and the Organization for the Advancement of Structured Information Standards (OASIS) to establish a generic web service architecture for providing common geoprocessing capabilities (e.g. spatial algorithms, map algebra, etc.) for usage in SDIs.  相似文献   

5.
将网格技术应用于地理信息领域,构建实现地理信息资源共享与协同工作的网格地理信息系统,是目前地理信息行业研究的热点之一。OGC制定的网络服务规范作为得到广泛支持的地理空间数据互操作规范。与网格技术的相关规范存在许多不兼容之处,使得OGC服务在网格体系下难于集成和管理。文章研究了OGC数据服务WMS,WFS和wCS的相关规范和OGSA—DAI网格中间件技术,提出将OGC数据服务扩展为OGSA—DAI的数据资源的方案,将WMS,WFS和WCS封装为符合WSRF的网格资源,实现分布式异构地理空间数据在OGSA—DAI框架下的访问、集成与管理。此方案提供了一种将OGC服务集成到网格环境中的方法,比较容易实现,对相关研发工作的开展具有很好的借鉴作用。  相似文献   

6.
分析了地理空间信息共享的重要性以及传统Web GIS在数据共享方面存在的问题,结合Web服务的自身优势,研究讨论了空间信息Web服务技术在空间数据共享方面的特点。针对空间信息共享需求,提出一种基于Web服务的空间数据共享应用框架。最后,基于ArcGIS Server10.0与.net技术,介绍了省级应急指挥GIS系统中的空间数据共享技术实现案例。  相似文献   

7.
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   

8.
Web服务技术为GIS空间数据的互操作提供了全新的、有效的解决途径,越来越多的GIS软件支持OGC Web服务规范。如何在单个应用程序中集成多个服务器上的Web地图服务是本文要解决的核心问题。首先阐述了本文的研究意义,然后对OGC Web地图服务及开发所采用的主要技术分别作了介绍;提出了Web地图服务集成共享平台的体系结构和相应的功能设计,并利用Servlets、JSP、JavaScript等技术对其进行了初步实现。  相似文献   

9.
Geospatial processing tasks like solar potential analyses or floodplain investigations within flood scenarios are often complex and deal with large amounts of data. If such analysis operations are performed in distributed web‐based systems, technical capabilities are mostly not sufficient. Major shortcomings comprise the potentially long execution times and the vast amount of messaging overhead that arise from common poll‐based approaches. To overcome these issues, an approach for an event‐driven architecture for web‐based geospatial processing is proposed within this article. First, this article presents a thorough qualitative discussion of different available technologies for push‐based notifications. The aim of this discussion is to find the most suitable push‐based messaging technologies for application with OGC Web Processing Services (WPS). Based on this, an event‐driven architecture for asynchronous geospatial processing with the WPS is presented, building on the Web Socket Protocol as the transport protocol and the OGC Event Service as the message‐oriented middleware. The proposed architecture allows pushing notifications to clients once a task has completed. This paradigm enables the efficient execution of web‐based geospatial processing tasks as well as the integration of geographical analyses into event‐driven real‐time workflows.  相似文献   

10.
采用WMS将公路交通专题地理数据与测绘框架地理数据进行集成与整合,实现跨行业和跨区域的空间地理数据的共享交互操作,并详细阐述系统的整体设计思路、系统架构及关键技术,最后对采用WMS在其它行业的应用进行展望。  相似文献   

11.
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   

12.
基于WMS的WebGIS   总被引:4,自引:4,他引:4  
介绍了Web地图服务规范,通过一种WebGIS的互操作模型实现了WMS,并详细描述了客户端的实现.  相似文献   

13.
For geospatial cyberinfrastructure-enabled web services, the ability of rapidly transmitting and sharing spatial data over the Internet plays a critical role to meet the demands of real-time change detection, response and decision-making. Especially for vector datasets which serve as irreplaceable and concrete material in data-driven geospatial applications, their rich geometry and property information facilitates the development of interactive, efficient and intelligent data analysis and visualization applications. However, the big-data issues of vector datasets have hindered their wide adoption in web services. In this research, we propose a comprehensive optimization strategy to enhance the performance of vector data transmitting and processing. This strategy combines: (1) pre- and on-the-fly generalization, which automatically determines proper simplification level through the introduction of appropriate distance tolerance speed up simplification efficiency; (2) a progressive attribute transmission method to reduce data size and, therefore, the service response time; (3) compressed data transmission and dynamic adoption of a compression method to maximize the service efficiency under different computing and network environments. A cyberinfrastructure web portal was developed for implementing the proposed technologies. After applying our optimization strategies, substantial performance enhancement is achieved. We expect this work to facilitate real-time spatial feature sharing, visual analytics and decision-making.  相似文献   

14.
In this paper we study the feasibility of using services offered by a Spatial Data Infrastructure as a basis for distributed service oriented geoprocessing. By developing a prototype we demonstrate that a Spatial Data Infrastructure facilitates rapid development of applications that solve typical problems for an existing risk management application. The prototype provides users with a distributed application that enables the assessment of fire damage areas based on land cover data in a given area. The services involved in the application include: Web Feature Services, Web Map Services, a Gazetteer Service, a Catalogue Service, and Geoprocessing Services. We present the architecture of the application and describe details about implementation‐specific issues. We conclude that current OGC specifications provide a sound basis for developing service oriented architectures for geographic applications; however, in particular for geoprocessing applications, we question the feasibility of the use of Web Feature Services as data sources for larger amounts of data and call for further research in this direction.  相似文献   

15.
16.
GML Server的设计与实现   总被引:1,自引:0,他引:1  
利用GML解决空间数据共享问题是当前的研究热门,在GML核心模式的基础上定制了大量的GML应用模式,GML数据大量涌现。然而缺少专门存储管理和发布GML数据的平台。本文针对OGC的服务规范,在对当前GIS服务器技术研究基础上,提出了GML Server服务平台,设计了一整套基于GML数据的Web服务系统。利用当前开源软件进行扩展,系统实现了发布基于GML数据的WFS,WMS,WCS服务及其各种空间分析查询功能。  相似文献   

17.
18.
提出了基于Web服务技术、OGC规范和工作流技术,以实现与平台无关的、具备流程编排能力的地理空间处理服务链框架,用于支持复杂的在线空间处理任务.在该框架基础上实现了一个在线遥感影像融合处理示例.该示例展示了利用OGC WCS、WPS,WSDL,UDDI和BPEL4WS等成熟的标准规范来构建GIS服务链,使得客户应用程序...  相似文献   

19.
首先详细讨论了目前主要的地理信息共享和互操作技术,包括Web Service,OGC的WMS/WFS,Map API,以及数据查询服务,分析了它们的特点及应用情况.并以此为基础,提出了基于Web Service服务的地理数据集服务框架,GIS数据以服务的形式在框架内发布,将各种服务集成是该框架下的主要开发模式.  相似文献   

20.
信息技术的日益发展,使得异构信息资源不断涌现,如何将这些异构信息进行集成成为迫切需要解决的问题。为了解决异构地理空间信息源的共享问题,本文研究了一种面向服务的地理信息共享模式,采用符合OGC标准的WFS、WMS等建立各种标准的服务,使得用户不但可以在网络上方便地调用各种地理空间信息,还可以通过标准的接口将各种标准的数据服务和功能服务与自己的应用系统进行集成,以及将来自不同软件提供的接口的数据进行共享。以武汉市为例,开发并实现了面向服务的地理空间信息公共服务平台,说明了通过标准的服务接口访问服务的方法,该平台在武汉市政务专网上得到了广泛应用。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号