Relation pm#relation_from_situation_to_time (situation,time_measure)
  exclusion:  relation_from_situation_to_situation
  supertype:  relation_from_situation  relation_to_time
  subtype:  time (situation,time_measure)
     subtype:  date (situation -> time_measure)
  subtype:  duration (situation -> time_measure)
  subtype:  from_time (situation -> time_measure)
     subtype:  departure_time__departuretime (process -> time_measure)
  subtype:  until_time__untiltime__to_time (situation -> time_measure)
     subtype:  arrival_time__arrivaltime (process -> time_measure)
  subtype:  before_time (situation,time_measure)