literature and in the market, there is not a single,
unique and uniform approach that leads the designer
from the domain description (often expressed in
ontological language) to the application design and
in particular to web application design.
Considering this gap, in this paper we introduce
a real experience into a complex environmental
domain. In the case study, we design a WA starting
from the domain knowledge base.
In the detail, we use the BWW methodology
(Wand, 2002) (Rosemann, 2005) (Colomb, 2002) to
describe the domain. This model is complete,
objective and simple to consult and has features of
abstractness and independence from the
development technology.
As WA design methodology, we consider the
IDM methodology that, even if focused on the WAs,
is independent from the specific development
technology widening the generality of our
considerations.
In this paper we present in the section 1 the
introduction and background and we focus on IDM
and BWW presenting them; in the section 2, we
present the process to derive an IDM design of the
application family starting from the BWW
conceptual model. In the section 3, we present a case
study: in the environmental domain first we design
the conceptual model and then we obtain the IDM
design of the family of applications; we obtain also a
specific application in the application family.
Finally, in section 4 we present conclusions and
future trends.
2 IDM & BWW IN A NUTSHELL
Interactive Dialogue Model is a design methodology
able to describe the communication structure of the
information-intensive application where the main
goal is to present information to the user; thus, IDM
maximises the dialogue between user and
application. The IDM notation uses graphical
element to model the main aspects of the application
using the dialogue content concepts. IDM is made
up of two different details level: Conceptual IDM
(C-IDM) and Logical IDM (L-IDM). C-IDM is used
to discuss with the customer about information and
navigation aspect. The designer uses the two main
IDM primitives: Topic (and Group of topics) and
Relevant Relation. Using these two primitives, a first
background about information and its relationship is
made. The L-IDM diagram is a detailed design. The
designer uses the Topic and the Relevant Relation
(as in C-IDM) but the detail level is more careful. In
L-IDM diagram, the topics are detailed using the
dialogue act that describes the content information.
In L-IDM, the designer can model the access
structures to the specific information. Each topic can
have one or more Introductory act that represents the
entry point to the topic’s information. L-IDM allows
to model the operation thought the operation act.
To model the page design that is not taken in
care in the IDM methodology, it’s possible to use
the design methodology named P-IDM (strictly
connected with IDM). P-IDM allows to organize the
information content in several views and each view
is made up of contents.
The main element in the ontology BWW
(Bunge-Wand-Weber) is the thing, which models
the "things" that have a physical existence in the real
world. The thing is characterized through the
Properties. Every thing has at least one Property
and every Property belongs at least one thing.
The properties can also be classified in Instrinsic
Properties, that regard a single thing, and Mutual
Properties that is shared between two or more
things. The Law can bind the value of the property.
There are two types of law: Natural (physics laws)
or Human (designer defined). A property can have
only one type of law.
The values assumed from the property define the
thing state. The Event can change the state because
can act on its thing. The chronological collection of
the several states constitutes the History, while the
set of events constitutes the Process. If a property
change of a thing modifies an other property of
another thing the two things are defined Coupled.
The things that have property in common can be
collected in class. The System is the collection of
things that are defined coupled.
More things can form a Composite thing when
they are essential part of its existence (as an example
the thing machine is a composite thing because it is
composed from the things engine, wheels, etc..).
3 THE MIGRATION PROCESS
Starting from these methodologies, we focus on the
process to derive the IDM diagram from the BWW
model correlating one by one the single elements of
two methodologies.
The final output of this process will be a general
model of a family of applications. From this model,
applying the specific requirements of the
stakeholders, it is possible to derive the IDM model
of a specific web application.
In fact, starting from domain model without
considering the specific stakeholders, the output
could be only general. This approach has the great
advantage that it is independent from the stakeholder
requirements and, thus, all the applications that
FROM THE BWW CONCEPTUAL MODEL TO THE DESIGN OF FAMILY OF WEB APPLICATION
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