Assume y is an 'activity profile', obtained from some containing activity z by selective abstraction on a quality q of a participant in z. Then, relate y by 'profile quantity datum' to magnitudes of q that are recorded during the execution of y.
Intuitively, 'profile quantity datum' should only point to quantity data recorded while the activity is taking place. This can not be enforced with OWL restrictions on the relation (it would require a "diamond" pattern). However, with a suitable date or time data property value restriction, an individual activity can constrain related quantity data.
