Organizing GI as Linked Data - Linked Data: A Geographic Perspective - page 96

TABLE 6.1
OGC RCC8 Properties

Relation Name OGC Relation URI

equals geo:rcc8-eq

disconnected geo:rcc8-dc

externally connected geo:rcc8-ec

partially overlapping geo:rcc8-po

tangential proper part inverse geo:rcc8-tppi

tangential proper part geo:rcc8-tpp

non-tangential proper part geo:rcc8-ntpp

non-tangential proper part inverse geo:rcc8-ntppi

TABLE 6.2
OGC Properties Mapped to RCC8 Relations
OGC Properties

Relation URI RCC8

equals geo:sf-equals Equals

disjoint geo:sf-disjoint Disconnected

intersects geo:sf-intersects Not disconnected

touches geo:sf-touches Eternally connected

within geo:sf-within NTPP + TPP

contains geo:sf-contains NTPPi + TPPi

overlaps geo:sf-overlaps Partial overlaps

NTPP = non-tangential proper part; NTPPi = non-tangential
proper part inverse;TPP = tangential proper part; TPPi
= tangential proper part inverse.

We discuss the difference between topological and mereological properties in more
detail further in this section. The OGC properties themselves do provide a good
basis on which to implement geographic properties as the relationships between
them are well defined and so can be used for inferring further properties. So, for
example, if we know that A is within B and that B is disjoint (separated) from C, we
can also infer that A is disjoint from C.
Merea Maps can use these OGC relations to define a set of properties suitable
to express the topological relationships between the objects that it records on its
detailed topographic maps. Merea Maps wants to use a “next to” relation to say that
two things are next to each other if they physically touch—two cottages side by
side within a terrace 5 would therefore touch. This is very straightforward as there is
already an OGC relation “touches” that seems to exactly meet these needs. 6 It can
use “touches” as is but decide instead to use the term “next to” as they feel this is
a more obvious term from the perspective of their users. 7 So, all they have to do is
specify that “next to” is a subproperty of “touches” and perhaps define a domain