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

64 CHAPTER 4. SEMANTIC ANNOTATION FRAMEWORK
section 2.2.1). Based on the semiotic triangle we can build the relationships between
model, meta-model, modeling language and ontology as shown in Figure 4.1. In the triangle,
a model is a conceptualization of referents and it is represented as a set of model
denotations in a certain modeling language. Model denotations are signs which signify
concepts in the model. The model is an instance of a meta-model, and the meta-model
defines a modeling language. A concept is a mental perception which is in a human’s
mind. One concept referring to a referent can be represented differently. On the other
hand, representations of different concepts may look similar in two models. The differences
are results of the way of conceptualization of modeling or representations of
model denotations defined in a modeling language. The semantic heterogeneity existing
in different models can therefore be distinguished at the model and the modeling
language level (we also call it the meta-model level).
Figure 4.1: Relationships between ontology, model, meta-model and modeling language in
the semiotic triangle
In order for a machine to understand the heterogeneous semantics in the models
(e.g. various signs of referents referring to the same concepts or synonym signs of
referents referring to different concepts), a common understanding of concepts has to
be formalized in a machine-interpretable way. An ontology is created for this purpose.
In the semiotic triangle, the semantics of concepts are formally in a standard i.e. they
are represented as an ontology. Ontologies aid the sharing of knowledge on the basis of
the assumption that there is a single reality and the sharing is a matter of aligning the
way different people or systems think about it [70]. Therefore, in the semiotic triangle