Web Feature Service

The Research Institute for Built and Human Environment (BuHu) http://www.buhu.salford.ac.uk / University of Salford, Salford, UK Construction and Property Research Centre, FBE, University of the West of England, Bristol, UK H.wang@salford.ac.uk ... Keywords: Web feature ...

The Open Geospatial Consortium (OGC) [1] defines a number of standards, both for data models and for online services, that has been widely adopted in the Geographical Information System (GIS) community. This has lead to a number of software development efforts, online data archives, and application communities. The emergence of Web Service technique overcomes the shortcoming of traditional Distributed Object technique and provides the interoperable capability of cross-platform and cross-language in distributed net environment. GIS services will be implemented more extensively by using Web Service approach. A spatial data infrastructure lets many GIS vendors share data stores and applications in a distributed environment. GIS basically involves the integration of data and services from multiple sources from different vendors. The Web services architecture establishes a standard interconnection rules between services and information clients that nicely support the dynamic integration ...

Geodetic Documentation Centers collect geodetic and cartographic resources. The resources include spatial data and their metadata. European Union INSPIRE directive imposes an obligation on GDC to publish selected data in the Internet. In this paper, an adequate form of publication is discussed on the base of iGeoMap application.

The Internet application iGeoMap merges data from various resources. Depending on the data to present, different types of resources are used. The application can publish spatial data from files (text or binary), a database specialized in spatial data service (PostgreSQL, ORACLE), or web services (Web Map Service, Web Feature Service). Utilization of various data sources by the application is presented in this paper.

As a part of the subject, searches of the  most popular data (parcels, address points, and control points) are discussed. Various data sources and searching mechanisms involved by the searches in iGeoMap are presented in use cases.

The Research Institute for Built and Human Environment (BuHu) http://www.buhu.salford.ac.uk / University of Salford, Salford, UK Construction and Property Research Centre, FBE, University of the West of England, Bristol, UK H.wang@salford.ac.uk ... Keywords: Web feature ...

OGC Web Services (OWS) are essential building blocks for the national and global spatial data infrastructure (NSDI and GSDI) and the geospatial cyberinfrastructure (GCI). Web Map Service (WMS), Web Feature Service (WFS), Web Coverage Service (WCS), and Catalogue Service for Web (CSW) have been increasingly adopted to serve scientific data. Interoperable services can facilitate the integration of different scientific applications by searching, finding, and utilizing the large number of scientific data and Web services. However, these services are widely dispersed and hard to be found and utilized with acceptable performance. This is especially true when developing a science application to seamlessly integrate multiple geographically dispersed services. Focusing on the integration of distributed OWS resources, we propose a layer-based service-oriented integration framework and relevant optimization technologies to search and utilize relevant resources. Specifically, (1) an AJAX (Asynchronous JAvaScript and eXtensible Markup Language)-based synchronous multi-catalogue search is proposed and utilized to enhance the multi-catalogue searching performance; (2) a layer-based search engine with spatial, temporal, and performance criteria is proposed and used for identifying better services; (3) a service capabilities clearinghouse (SCCH) is proposed and developed to address the service issues identified by a statistical experiment. A science application of data correlation analysis is used as an example to demonstrate the performance enhancement of the proposed framework.

Communities that want to share information often do not know enough about the available standards or how to choose the best one. One is example is marine communities that want to share observation data. Even selecting a standards body, such as the Open Geospatial Consortium (OGC), is not enough. For example, OGC has more than one standard that could potentially be used to publish time series data: sensor observation service (SOS), Web feature service (WFS) and Web coverage service (WCS). To better assess these standards requires testing and evaluation in end-to-end demonstrations. An end-to end prototype spans from publishing sensor deployment information to visualizing in a Web client data from a remote Web service. OOSTethys is a community initiative that has been advancing standardized components in end-to-end prototypes for marine observations. OOSTethys participants initiated an OGC Ocean Science Interoperability Experiment (Oceans IE) in 2007, to advance the interoperability of ocean observing systems by using OGC standards. The Oceans IE Phase I investigated the use of WFS and SOS for representing and exchanging point data records from fixed in-situ marine platforms. The study found that 1) SOS contains the necessary components to represent observations, not only from sensors, but also from sensor systems; 2) communities that adopt SOS instead of WFS will not be required to create and maintain their own specifications, which specify the rules of encoding, such as XML schemas; and, 3) the SOS model and weak typing approach provides a sufficient balance to allow general structure and community semantics to co-exist; however, this requires an effort in creating and maintaining controlled vocabularies by marine communities. The result is not only relevant to the marine community but to any community that is sharing geo-spatial observations.

SUMMARY In this paper we study the feasibility of using services offered by a Spatial Data Infrastructure as the basis for distributed service oriented geoprocessing. By developing a prototype we demonstrate that a Spatial Data Infrastructure facilitates rapid development of applications that solve ...