The term "structure" is massively overloaded and can be used for many different things in different context by different people (including SysMLv1 experts)
It can be used to mean at least the following:
- Containment structure of the model as can be indicated in both Package Diagrams and BDDs, including use of Package and Model elements with graphical containment owned elements and/or the Containment operator.
- Compositional structure (such as hierarchical assemblies) using Blocks and part properties. This is typically shown in an IBD but might also be indicated in a BDD using aggregating Associations or using the structure compartment on a Block symbol, which acts as "mini" IBD within a BDD.
One way to tell the difference between these main usages is that in SysMLv1 terminology the "model" is not the system of interest; the "model' is (usually) considered to be all those elements you see in the project browser of your tool. The "model" is used to model your system of interest. The system of interest has a structural decomposition (whole parts relationship hierarchy).
It is easy to conflate "the model of the structure of your system" (a structural model model) with the structure of the model itself.
Is the term 'structure' used consistently throughout the SysMLv1 specifications?
No. And the meaning depends on the context within the document.Has the term 'structure' ever been used 100% consistently throughout any document in the entire history systems engineering ?
Probably not. Maybe.If you are studying for the OCSMP exams you need to be aware of these possible different meanings, and exercise common sense in interpreting the intention and context of the terminology of questions.