The fact that GML is an XML encoding allows it to be queried. In order to query a GML document we have designed a query language over GML/XML enriched with spatial operators. This query language has an underlying data model and algebra that supplies the semantics of the query language. In this paper, we propose an approach for integrating Geospatial data on the Web, stored in GML documents, usi...

Geography Markup Language (GML) has been established as the standard language for the transport, storage and modelling of geographic information. In this paper we study how to adapt the XPath query language to GML documents. With this aim, we have defined a semantic based XPath language which is not based on the (tree-based) syntactic structure of GML documents, instead it is based on the “sema...

This paper presents a study of Geography Markup Language (GML), the issues that arise from using GML for spatial applications, including storage, parsing, querying and visualization, as well as the use of GML for mobile devices and web services. GML is a modeling language developed by the Open Geospatial Consortium (OGC) as a medium of uniform geographic data storage and exchange among diverse ...

GML is the encoding specification of geospatial data, currently more and more geospatial data are represented in GML documents. In order to query GML data efficiently, appropriate index structure should be designed. As the application of XML in geospatial information field, the management of GML data can borrow ideas from the management technologies of XML data. Two types of existing XML path i...

Resumo. Dados representados em documentos GML são utilizados em diversas aplicações GIS e na Web visando principalmente o armazenamento, a manipulação e a troca de informações geográficas. Entretanto, uma grande parte das informações geográficas estão armazenadas em bancos de dados espaciais. Este trabalho apresenta uma metodologia para mapear dados geográficos, estruturados usando relacionamen...

With regarding to web GIS, OGC promotes WFS allowing a client to retrieve geospatial data encoded in GML which is a modeling language to encode the semantics, syntax and schema of geospatial information resources. Even though GML provides benefits for geographic description, it is too heavy to be processed by mobile devices. In order to address the issue, this paper evaluates GML service with W...

The National Spatial Data Infrastructure (NSDI) is defined as the technologies, policies and people necessary to promote sharing of geospatial data throughout all levels of government, the private and non-profit sectors and the academic community. The US Census Bureau is the federal agency lead for administrative units data, one of the seven data themes identified by the NSDI framework. The adm...

The Geography Markup Language (GML) is a standard XMLbased language that enables the representation and easy interchange of geographic data between Geographic Information Systems (GIS). In this paper, we explored the compressibility of GML performing some empirical experiments over real GML corpus using a wide set of wellknown compressors. In particular, the main characteristics of GML are firs...

Geography Markup Language (GML) has been established as the standard language for the transport, storage and modelling of geographic information. In this paper we study how to adapt the XPath query language to GML documents. With this aim, we have defined a XPath based query language which handles the “semantic structure” of GML. Our approach focuses on querying urban maps whose representation ...