October 2006 Volume 9 Number 4

Step 1: Instantiation of the enterprise viewpoint. The reverse engineering of a TEL system needs a dialog
between the software engineering process and the design process. It is this interaction between these two
enterprise objects, grouped in a same community, which is modeled from the enterprise viewpoint, as shown in
Figure 4 with ECA notation.
Reverse Engineering
Community
Design
Process
t
Designer / Engineer
Protocol
Engineering
Process
Engineer / Designer
Protocol
Figure 4: Instantiation of the Enterprise Viewpoint
Step 2: Instantiation of the information viewpoint. The role of the design process, instigator of the dialog, is to
produce a specification of the TEL system, from the information viewpoint. We have used the different
information formalisms provided by the IMS consortium for our test. Figure 5 is an excerpt from the
instructional scenario, modeled in IMS Learning Design and IMS Content Packaging. It shows the environment,
made up of two objects, chosen by the designers to support the activity "Going Into Matter". The object
"knowledge-object" is the HTML document "author_text1.html" which contains the pedagogical content. The
object "tool-object" is the Java component "manager.jar" which handles the diffusion of the document. In fact,
according to Koper (2001), when designers choose to present the pedagogical content ("knowledge-object"),
they explicit the need of the support object ("tool-object").
…
…
Figure 5: Excerpt of the Instructional Scenario
Step 3: Instantiation of the software engineering viewpoint. When the design process provides its specification,
the software engineering process needs to identify and characterize, in a modeling task, the states of the objects
introduced by the specification. Guided by the RM-ODP framework, a software engineer knows that he needs to
identify three schemas (ISO/IEC 10746-3, 1996, Chapter 6.1):
the Invariant Schema is a set of predicates and relations on information objects which are always true;
the Static Schema defines the state of the information objects at some point in time;
the Dynamic Schema is a specification of the allowable state changes of the information objects, subject to
the constraints of an invariant schema.
Here, the static schema is the set of models defined by the proposals Learning Design and Content Packaging of
IMS and Content Package of ADLNet, to which are issued the information objects of the designers' specification
(imscp:file, imscp:resource, imsld:item, imsld:environment, imsld:learning-object and adlcp:scormtype). The
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