ontology, the domain ontology is created by
formally describing the intension of each concept
and their intentional relations.
During our research, we used the top-level
ontology DOLCE (Masolo, Borgo, Gangemi,
Guarino, Oltramari, 2003) and one of its modules
D&S (Gangemi, Mika, 2003). Other top-level
ontologies might be used.
2.3 Views and Facets
In our approach a view is a model of an IS related to
a particular, homogeneous from a logical point of
view, set of concerns. We consider that the concerns
emerge from a particular perspective of the IS
developing process: social, functional,
informational, or technological perspective.
Therefore, depending on the perspective applied, we
obtain social, functional, informational, or
technological views. The views are models of a
future or existing IS resulting from a projection of
the system in a large area of concerns belonging to
more stakeholder roles. In this paper, we consider
only the informational views.
An informational view is a structural model of
the system to be modelled, basically a UML class
diagram (UML, 2003). It contains categories in the
system’s conceptual domain, their relations, as well
as constraints regarding the model interpretation.
We also consider an informational view as a
cluster of facets. Each facet is a simplified model of
the informational view and conceptually represents a
concern-driven abstraction of the informational view
according to a stakeholder’s paradigm. This
paradigm is shaped in time by stakeholders playing
the same role or having the same responsibilities.
Confronted with similar situations the stakeholders
manifest similar concerns and build similar solutions
for solving these concerns. We can say that a facet
describes the semantic rationale of a concern.
Technically, a facet is constructed according to a
template that contains the following fields: the codes
of the facet and concern, the dependency graph of
beliefs and knowledge for a semantic rationale of the
concern and the facet semantics represented as a
UML class diagram that contains the participating
concepts and their ontological relations extracted
from the domain ontology.
The template associates the semantic rationale of
the concern to the concern semantics as it is derived
the knowledge and beliefs of a concern’s semantic
rationale. In the next subsection, the UML
ontological model is defined.
2.3.1 UML Ontological Models
An UML ontological model is a class diagram that
semi-formally describes the semantic of a piece of
knowledge or belief of a concern’s rationale. Such
model is constructed from the domain ontology of
an IS trying to preserve its semantic. It uses concepts
of the UML metamodel like class, data type,
association, and dependence (UML, 2003). In our
research, we found that the correspondence between
these concepts and the categories and conceptual
relations of the domain ontology (constructed using
the top-level ontology DOLCE+D&S) is expressed
in the following rules:
1. All categories of the domain ontology, excepting
the abstracts and formal roles, are mapped to
classes.
2. The material roles are mapped to association
classes and the formal ones are mapped to
association roles.
3. Categories subsumed by abstract category are
mapped to the data type UML concept. A data
type is a type whose values have no identity
(UML, 2003).
4. All ontological relations, excepting parthood,
constitution, and subsumption are mapped in
associations in UML ontological models. An
association is a relation that describes semantic
connections between individuals that are
instances of the given classes (UML, 2003).
5. Temporal and temporary parthood, also
constitution relations are mapped in UML
aggregation relations (UML, 2003).
6. The subsumption relation is mapped to the UML
generalization/specialization relation. As it is
known, the subsumption relation holds between
two categories A and B (and we say, “A
subsumes B”) of an ontology if and only if, for all
possible states of affairs, all the instances of B are
also instances of A. Using UML language we
express the same semantic saying that B is a
subclass of A.
In order to construct an UML ontological model
of a piece of knowledge or belief, our approach
proposes the applying of the abstraction mechanism
and the following rules on its mental representation
description in the natural language:
1. If a concept from the mental representation
corresponds to a category from the domain
ontology, we map this category and the category
or categories from the foundational ontology that
subsume it into classes or data types.
2. If a concept corresponds to a quality from
foundational or domain ontology, the model will
contain the corresponding class and, in addition,
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