Mobile and Semantic Web-Based Delivery of Context-Aware Information and Services in Construction - Mobile and Pervasive Computing in Construction - page 19

multiple information sources, on an ad hoc and on demand basis. Similar
approaches to semantic description of resources have been adopted in other
projects such as Mummy (2003), Artiste (2003) and OTK (2002). The ontol-
ogy-based project database/repository developed was called OntoWise.

2.6 OntoWise

OntoWise is an ontology-based data sharing application/repository that was
developed for automated data sharing in a typical construction project. It is
based on OntoShare (Davies et al ., 2002) - a knowledge management system
developed as part of the European Union project OntoKnowledge (2002) for the
creation of a semantically annotated data repository that facilitates project doc-
ument storage and distribution. Ontoshare includes an ontology editor wherein a
domain specific ontology can be defined. The different stakeholders in a project are
designated as the system users and the application models the interests of each user
in the form of a user profile. In OntoWise, user profiles are sets of ontological
concepts/classes declared in RDF(S) (RDF Schema) in which the user has expressed
an interest or is a part of. OntoWise also has the capability to summarize and extract
key words from project documents and drawings shared. Using push technology
there are algorithmic methods (Davies et al ., 2002) methods to share this infor-
mation with other users in the project team whose profiles indicate interest in the
information. This is particularly useful in the context of the mobile user on site who
is searching for specific information.
Each document/drawing that is uploaded into OntoWise leads to the creation
of a new entry in the project database. This database is effectively an ontology
represented in RDF(S) and RDF. RDF(S) is used to specify the classes in the
ontology and their properties. RDF is then used to populate this ontology with
instances as documents and drawings are added. Figure 2.5 shows a high level
version of the ontology for a project team sharing information about a building
project, along with an example of a single shared drawing (Drawing_1). In the
figures, the class Building and its subclasses are the concepts which the project
users are interested in. Another key class is Drawing, which is the class used to
represent shared information: each shared drawing generates an instance of
Drawing with the set of properties shown. Drawing_1, for example, was stored
by D.Ruikar into the concept joint_a with the annotation “Details of Joint_a

”
with the summary and Uniform Resource Identifier (URI) as shown in
Figure 2.5. It also has a set of keywords associated with it. For simplicity
only one keyword, Kw_1, is shown, which is an instance of the class Keyword, as
is Kw_2. Furthermore, the instance (typeOf) relation is not shown for these
keywords, nor is the fact that Keyword is a subclass of rdfs#Resource. The third
central class is Profile , instances of which represent user information, including
the concepts in which they are interested, their names and email addresses.
Profile_1, for example, is the profile of a user with name “D.Ruikar”. Keyword
Kw_2 is one of (possibly) many terms (words and phrases) which characterize
the concept “Joints”.

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