Semantic Annotation for Process Models: - Department of Computer ...

146 CHAPTER 9. VALIDATION OF APPLICABILITY
Both the antecedent and consequent consist of zero or more atoms. Atoms in these
rules can be of the form C(x), P(x,y), sameAs(x,y) or differentFrom(x,y), where C
is an OWL description, P is an OWL property, and x,y are either variables, OWL
individuals or OWL data values. A "human readable" form of a SWRL rule is:
antecedent → consequent
where both antecedent and consequent are conjunctions of atoms written a 1 ∧ ... ∧
a n . Variables are indicated using the standard convention of prefixing them with a
question mark (e.g. ?x) [202].
SWRLTab and SQWRLQueryTab
The SWRLTab [151] is a development environment for working with SWRL rules in
Protégé-OWL. It supports the editing and execution of SWRL rules. It also provides the
mechanism to turn SWRL into a query language – SQWRL (Semantic Query-Enhanded
Web Rule Language). The SQWRLQueryTab [150] is a plug-in to the Protégé-OWL
SWRLTab and it provides a convenient way to visualize the results of queries on an
OWL ontology. In the evaluation, we employ SWRLTab to formalize the requirements
from section 9.1.1 into SWRL rules in order to validate the annotation results. Most
of the rules are queries which can return the query results in SQWRLQueryTab. The
SQWRL provides SQL-like operations to retrieve knowledge from an OWL ontology.
9.2 Application Requirements in SWRL Formulation
In the exemplar studies, the BPMN model (PM A ) and the EEML models (PM B1 and
PM B2 ) are annotated by the proposed approaches. Those three models are to be shared
with each other and integrated in a process knowledge management application. The
application requirements are formalized into a set of SWRL queries and rules which
are executed on those annotated models. The queries and rules are generally defined
for all models, but they can be also specified by replacing the variables with certain
values for specific models.
9.2.1 Formalizing RE1 - Navigation requirements
RE1 is related to G1 (The annotation should improve the readability and comprehensibility
of the existing process models). The sub-requirements identify what knowledge of
the process models should be read directly from the annotation results. The requirements
in RE1 are formalized in Table 9.1.
9.2.2 Formalizing RE2 - Search requirements
RE2 is related to G2 (The annotation should help sharing process knowledge among different
organizations within a domain). The search should look up all the three models
without problems associated with semantic heterogeneity. A domain ontology which
acts as the common understanding of the domain is essential in supporting the machine