One of the benefits of enterprise modelling is the
ability to analyse business processes for reaching
agreement among various stakeholders on how and
by whom the processes are carried out. The
industrial versions of information system modelling
methods that are intended for business process
modelling do not explicitly use the concept of value
flow. Value models, which include resource
exchange activities among actors, can be viewed as
design guidance. The declarative nature of value
flows is very useful from the system analysis point
of view for the simple reason that flows have very
little to do with the dependencies between business
activities. Each value flow between actors, that can
play the role of service requester and service
provider, can be further refined in terms of more
specific coordinating interactions among
organizational components. The way of modelling,
which is based on service flows, is more
comprehensible and thus more suitable to discuss
changes of process architectures with business
developers, enterprise architects, system designers
and users. Business process modelling does not deal
with the notion of value flow, which demonstrates
value exchange among actors involved (Gordijn et
al., 2000). Traditionally, information system
methodologies are quite weak in representing the
alternative value flow exchange scenarios, which
usually represent the broken commitments.
Bunge (1979) provides one of the most general
ontological definitions of a system. In this paper, his
definition serves as the theoretical basis for
understanding the notions of organization and
enterprise ontology (Dietz, 2001). Bunge’s
ontological principles are fundamental for the
justification of various conceptual modelling
constructs in our semantically integrated modelling
method (Gustas and Gustiene, 2012). These
principles are as follows: enterprise system can be
decomposed into subsystems, which are viewed as
interacting components; every subsystem can be
loosely coupled with interactions to other
subsystems; when subsystems interact, they cause
certain things to change and changes are manifested
via properties.
Any subsystem can be viewed as an object, but
not every object is a subsystem. According to
Bunge, only interacting objects can be viewed as
subsystems. It is quite beneficial to specify service
interactions and to keep track of crosscutting
concerns (Jacobson and Ng, 2005) between different
subsystems in order to justify their usefulness.
However, a basic underlying principle in UML is to
provide separate models for different aspects. It is
not totally clear how these aspects can be merged
back into one model. Subsystems in UML cannot be
realized as composite classes. UML does not
provide any superimposition principles of static and
dynamic aspects. There is very little research done
on how the structural aspects and state dependent
behaviour of objects should be combined with use
case models. Classes and their associated state
machines are regarded as the realization of use
cases. Use case diagrams are typically not
augmented with specification of state related
behaviour (Glinz, 2000).
System decomposition should be strictly
partitioned. Every component partitions a system
into parts, which can be loosely coupled with other
components without detailed knowledge of their
internal structure. Object transitions and structural
aspects have to be related to one separate service,
which consists of organizational or technical
components. The limitation of conventional system
modelling methods results in two side effects, better
known as tangling and scattering in aspect-oriented
software development (Jacobson and Ng, 2005). The
treatment of these deficiencies requires the
modification of UML foundation. Introducing
fundamental changes into UML syntax and
semantics with the purpose of semantic integration
of collections of models is a complex research
activity. However, such attempts would allow using
UML to provide computation-neutral type of
diagrams, which are more suitable to reason about
enterprise architectures. It is recognized that UML
support for such task is vague, because semantic
integration principles of different diagram types are
still lacking (Harel and Rumpe, 2004).
3 VALUE FLOW EXCHANGES
AND TRANSITIONS
Semantically integrated conceptual modelling
paradigm is based on more rigorous interpretation of
human work. A new conception helps us to develop
the method of enterprise engineering that allows
practitioners to see the sources of breakdowns, the
connections to systems design and to guide the
redesign of work processes towards greater
productivity and customer satisfaction. Business
process models of organizations are quite good for
viewing moving material and information flows, but
they provide no mechanism for ensuring that the
service requester is satisfied. Service requesters deal
with work processes to be done, agreements on what
Interactions, Transitions and Inference Rules in Semantically Integrated Conceptual Modelling
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