6.3 Suspended Ceiling Design Process - Bilkent University

However, like the other graph-based representations, IDEF0 also
suffers from size limitations. It tends to grow rapidly for a large number
of tasks and visual inspection of the information structure becomes very
complex and misleading. Thus, it is more useful for high-level process
representations rather than detailed processes. Moreover, process
modeling techniques like SADT/IDEF0 are only well structured when the
activities constitute the focus. Information, controls and mechanisms are
connected to each process step but there is no way of analyzing the
total information structure processed in the system. Although IDEF0 is
capable of showing iterations in processes, it does not provide a means
of resolving them (Svensson et al., 1999). Another limitation of the
IDEF0 technique is that mainly document producing actions are
captured. The technique gives weak support for modeling parallel sub-
processes and for informal communication within a sub-process.
Therefore, iterations between levels are difficult to analyze with IDEF0
(Malmström et al., 1999).
3.2.2 Entity-Relationship Diagrams
Information modeling methods like Entity-relationship (ER) diagrams
and UML were originally developed for designing software intensive
systems. ER diagrams were specifically developed to build relational
databases. The method utilizes three major abstractions to describe the
data; namely, entities, relationships, and attributes. The basic object
that an ER model represents is an entity, which is a “thing” in the real
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