APPENDIX C

Events with Duration

In most versions of the event calculus, event occurrences are instantaneous. This appendix presents a revised version of EC that allows event occurrences with duration. A three-argument Happens predicate Happens3(e, t1, t2) is introduced, representing that event e occurs between t1 and t2. EC is revised as follows.

DEFINITION EC1′

Clipped(t1, f, t4) image

e, t2, t3 (Happens3(e, t2, t3) ∧ t1t3t2 < t4Terminates(e, f, t2))

DEFINITION EC2′

Declipped(t1, f, t4) image

e, t2, t3 (Happens3(e, t2, t3) ∧ t1

Get Commonsense Reasoning now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.