A Cloud-Based, Geospatial Linked Data Management System - Transactions on Large-Scale-Data-and Knowledge-Centered Systems XX - page 72

results in a map-based GUI, this along with the previous method constitute
added-value functionality useful for building geospatial applications.
- INSPIRE export: This method can be used to export the LD stored in INSPIRE.
The input required for this method is the geospatial theme for which the
data need to be exported as well as a set of SPARQL FILTER constraints
which impose filtering conditions on the data to be returned. Internally, each
theme is mapped to a particular SPARQL query which is first joined with
the FILTER constraints and then issued to the underlying store. The results
obtained are mapped to INSPIRE based on a particular mapping from the
geo-scientific spatial observation model (GSOM) [ 10 ]toINSPIRE.GSOM
has been proposed at the conceptual level as a means to integrate the various
information sources involved in the InGeoCloudS project and as well as an
information model that complements INSPIRE in particular aspects, such as
the complete modelling of events and geo-scientific activities. To this end,
the GSOM-to-INSPIRE mapping involved in the realization of this method is
incomplete due to the fact that some GSOM information is not included in
INSPIRE.
- inspire query export: This method is also able to export LD in INSPIRE for-
mat. The difference with respect to the previous method lies on the fact that a
direct (Geo)SPARQL query is provided by the user which is used to fetch the
SPARQL results and then transform them into the INSPIRE format. Inter-
nally, the method is able to recognize the theme(s) involved in the query as
well as the mappings from SPARQL variables to GSOM entities and based on
these to perform the LD to INSPIRE transformation.
- theme query info: This method takes as input the name of one theme and
returns to the user useful information that can be used to invoke one of
the previous INSPIRE export methods. The information returned includes
the exact SPARQL query issued as well as the names of the variables that
can be filtered along with a short description of their semantics and their
domain of values. Through this information, the user can understand which
filtering conditions suit his/her needs and then use them either to invoke the
inspire export along with the theme name or the inspire query export method
via joining the theme's SPARQL query with the desired filtering conditions
and using the result as input to this method.
- addXSLMappings: this method can be used to indirectly import the data of a
provider into the underlying triple store through exploiting as input an XSLT
specification which indicates the way the provider's XML-based data can be
transformed into RDF ones.
The last method completes the import capabilities of the LMS which relieve
the user from the peculiarities of the publishing process by also enabling him/her
to provide the less possible input and can cater for different LD publishing
cases: (a) the provider directly imports the LD him/herself and has the direct
control of what is imported. If his/her data are not in LD form, then obviously a
transformation is needed. This publishing way is appropriate when the provider's
original data are in LD form or when he/she desires to transform a portion of