Spatial and Temporal Information Retrieval in Textual Corpora - Geographical Information Retrieval in Textual Corpora - page 22

Language (GML), the visualization of data with Keyhole Markup Language (KML),
or annotation in the case of SpatialML and ISO-Space.
A widespread spatial modeling language of type interchange format is GML.
Defined by the OGC 12 , allowing the storage of geographic objects, in particular their
corresponding geometries (numeric representations). In addition, GML has been
designed to be used within other derived languages of XML. It only handles numeric
representations (and therefore not symbolic representations). In the example of “to
the south of Pau”, a Polygon-type representation (<gml:Polygon>) is associated with
it together with the latitudes/longitudes corresponding to the different points.
KML 13 is another widely known spatial modeling language of interchange format
type; also defined by the OGC, it is mainly used in GoogleMaps and GoogleEarth.
Like GML, it handles numeric representations, however, it is capable of describing
styles associated with the visualization of these representations. Thus, in the example
of “to the south of Pau” it associates a representation of type Polygon (<Polygon>)
togetherwiththelatitudes/longitudesofthedifferentcorrespondingpoints.Moreover,
information relative to the visualization (e.g. color and line thickness) is associated
with these coordinates.
SpatialML 14 [MAN 08a] is a spatial markup language supporting knowledge
description. It was developed by the American organization MITRE 15 . SpatialML
handles the numeric representations of places (the PLACE tag). It also models spatial
relations (SIGNAL and LINK tags), which it only stores as symbolic representations
(see Figure 2.2 for the different types of relations). Listing 2.2 illustrates the
SpatialML code of the representation of “to the south of Pau”. As we can see, the city
of Pau is identified and associated with coordinates; the relation of orientation (south
direction) is also described but there is no associated numeric representation.
1 <SIGNAL id ="1" type="DIRECTION">south </SIGNAL>
2PLACEi d="2"count ry="FR"form="AM"l at l ong="43. 301667N
−0.368611W">Pau</PLACE>
3PLACEi d="3"/ >
4<RLINKi d="4"di st ance="2"di rect i on="S"source="2"t arget ="3"
signals="1"/>
Listing 2.2. Example of SpatialML markup for (to the south of Pau)
12 The Open Geospatial Consortium (OGC) is an international consensus that proposes open
formats for geographic information - http://www.opengeospatial.org/.
13 http://www.opengeospatial.org/standards/kml/.
14 http://www.mitre.org/work/tech_papers/tech_papers_09/09_3827/.
15 http://www.mitre.org/.