6.3 Suspended Ceiling Design Process - Bilkent University

world with an independent existence. Each entity has particular
properties called attributes that describe it. A particular entity will have a
value for each of its attributes. Whenever an attribute of one entity type
refers to another entity type, some relationship exists. In the initial
design of entity types, relationships are typically captured in the form of
attributes. As the design is refined, these attributes are converted into
relationships between entity types (Elmasri and Navathe, 1994).
Figure 3.6: A Part of a Process Model as an Entity-Relationship
Diagram (Hong and Hong, 2001)
Hong and Hong (2001) have developed an entity-relationship based
process model for structural design. They claim that entity-based
approach to process modeling enables them to develop integrated and
uniform product and process models. The ER diagramming was also
used for building a relational database for GDCPP Map Creation tool by
mapping the entities and relationships as database tables (Wu et al.,
1998).
Activity-type entity
n
relationship
m
Activity-type entity
attribute
attribute
[value set]
action
input(data:data type)
output(data:data type)
expressions
[value set]
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