You can create a node tree diagram to view the hierarchical relationship between Operational Activities in a nesting of parent/child OV-5 diagrams of a model.
To create a node tree diagram
1 Click File > New Diagram or select Diagrams in the All Methods tab in the explorer, right-click it, and then select New.
2 In the Select new type for All Methods dialog box, scroll down and double‑click OV-5 Node Tree.
3 Type a name; then click OK.
The diagram is created.
4 To automatically generate a node tree inside the diagram for an operational activity, complete these steps:
Click Draw > Decomposition.
In the Select for Node Tree Generation dialog box, in the box containing the list of diagrams, find the starting diagram for the tree (generally the Context diagram); then click the expand symbol (+) at the left side of the diagram name.
Select the Operational Activity symbol that you want to decompose; then click Build.