Database Reference
In-Depth Information
unique about GI. Perhaps the things that have made it special in the past, such as its
concentration on geometry, will be less important in the Semantic Web era, help-
ing to make GI more accessible. We argue that it is the ability of GI to facilitate the
integration of other data that is of real interest in the context of the Semantic Web.
The Semantic Web is
about reasoning over data and integrating
data
; it there-
fore makes sense that GI, as an enabler for integration, and the Semantic Web are
natural bedfellows.
There are peculiarities about GI that present particular challenges with respect to
the Semantic Web. Geometry is certainly one of them, and there are others, such as
the application of topologic networks and the vagueness that exists in geographic cat-
egories. For example, what makes a river a river and not a stream? Again, it is worth
emphasizing that these peculiarities are not unique to geography. And, it is not always
possible to provide complete solutions to these problems. In these cases, we therefore
suggest how best to manage the problems, compromising an unobtainable ideal for
the best practical solution permitted by contemporary technologies and information
theory. It is the intention of this topic to cast light on the main challenges of using GI
within the Semantic Web and explain the best practice for its use, as bounded by the
constraints of current technology and knowledge.
1.4
EXAMPLES
To explain the application of Semantic Web and Linked Data techniques to GI,
we make copious use of examples. In places we have done so in a way that shows
how an organization may develop its solutions, and to do this we have decided to
create an imaginary country—the island state of Merea—along with a number of
organizations within that state. Principal among these is Merea Maps, an imaginary
national mapping agency. Merea Maps appears very prominently partly because we
both have worked for such an organization and are thus familiar with the challenges
faced by mapping agencies. But more important, the work of mapping agencies
provides a rich selection of examples in their task of not simply producing mapping
but of creating digital representations of the world where we live. In doing so, they
encounter a multitude of interesting challenges and face a world where precision
is not always possible and uncertainty is faced on a regular basis. The data they
produce is used as a fundamental component of many other applications; therefore,
we can also follow the story of this data, from how it is collected and represented
by Merea Maps through how it can be combined with other data by a third party to
address specific problems.
Merea Maps is intended to be a mirror of any modern mapping agency. For those
not familiar with mapping agencies in the twenty-first century, it is worth empha-
sizing that these organizations are not simply responsible for providing traditional
paper mapping. Their main role is to supply high-quality digital information about
the topography related to their area of interest. In many countries, this responsi-
bility may also extend to hydrographic mapping and maintaining a land cadastre
(a registry of who owns what land). However, for the sake of simplicity Merea Maps
