|Describe and draw the specialization/generalization hierarchy of concepts associated with points in time and time intervals.
As an inpiration we can mention such concepts as date, time, day, week, month, and year.|
Is there a common generalization of points in time and time interval?
Is there an aggregation relationship between the two concepts?
Describe some useful properties (operations) of the two concepts.
What is the relationships between the designed concept hierarchy and the calendar concept?