SYSML12 — Ports use property type incorrectly

Ports use property type incorrectly. Atomic flow ports use the type of the port for the type of thing flowing. This doesn't fit common usage in engineering design, for example, a port that is a faucet through which water flows. The type of thing flowing isn't the type of the port, it should be associated to the ports by the stereotype. Non-atomic flow ports use the type of the port for an interface with properties specifying the type of things that flow. If the various types of things flowing are intended to flow at the same time, then flow specifications aren't needed. This can be done with an atomic port flowing objects supporting the interface. If the the various types of things flowing are meant to flow at different times, this is isn't UML semantics. This can be done either with 1) an atomic port flowing a supertype of the various types of things that flow 2) the association mentioned in in the first paragraph having multiple types, which the semantics defined to be union of the types.

The atomic port portion of this issue is addressed in the resolution of issue 13178
by deprecating atomic flow ports. See resolution of issue 14424 regarding nonatomic
flow ports.