Meet the need of building project the er matrix

meet the need of building project. The ER Matrix
includes structural ERs and other ERs for collabora-
tive design. This study provides two ways to define
the ERs, that is, a UI and an XML-based language.
Subsection 2.1 describes these two ways in detail.
2. Import an IFC data model: the structural engineer
can use a structural software tool to build an origi-
nal structural model according to structural ERs
defined in the ER Matrix, and then store this native
model using IFC format. This IFC data model will
be imported into the proposed tool for generating
the required model data.
3. Judge the IFC release: an IfcReader module was
developed to interpret IFC data model. When the
structural model is imported, its IFC release is
judged to be IFC2x3 or IFC4, and then the IfcRead-
er interprets different kinds of objects and their at-
tributes from the original model.
4. Map the ERs to IFC data: according to the mapping
between the ERs and IFC data, the Er2StruIfc mod-
ule queries required information in the original IFC
model. If the required information cannot be ob-
tained, error messages will be collected in an error
report. The exchange model generation algorithm
in the Er2StruIfc module is elaborated in Subsec-
tion 2.2.
5. Export the exchange model or error report: through
the IfcWriter module, the target IFC data will be
integrated to form an IFC model. If the exchange
model fulfills requirements in the ER Matrix, it will
be delivered to downstream applications; if not, an
error report generated by the ReportWriter module
will be returned to the structural engineer for modi-
fication.
While the last three steps are conducted by corre-
sponding modules, designers are only required to com-
plete the first two steps. Within these two steps, designers
are able to define the required information according to
various civil engineering projects through the proposed
ER Matrix, and it avoids a manual mapping between the
ERs and IFC data. In the light of providing better sup-
port in the exchange model generation based on the user-
defined ERs, the following subsections introduce (1) two
ways to define the ER Matrix (that is, user interface and
XML-based language), and (2) an exchange model genera-
tion algorithm in the Er2StruIfc module, which enables
the mapping between the ERs and IFC data.
2.1. ER Matrix definition
This study mainly targets the definition of the ER Matrix
in two interchangeable forms: an intuitive UI with effective
interaction, and an XML-based language to define the ERs.
As mentioned above, a default ER Matrix is provided
for the delivery of structural design information for col-
laboration. Through the proposed UI, the users can di-
rectly browse and use the default matrix to deliver tar-
get model data. As shown in Figure 9, the options (R/O/
Empty) for all attributes of structural objects are presented
when importing the ER Matrix. The ERs in various proj-
ects may be different from those in the default ER Matrix,
so the UI can be used to modify the options of several
ERs to meet the demand of the specific project. For the