摘要：This paper extends a standard process algebra with a time-out operator,thereby increasing its absolute expressiveness, while remaining within therealm of untimed process algebra, in the sense that the progress of time is notquantified. Trace and failures equivalence fail to be congruences for thisoperator; their congruence closure is characterised as failure traceequivalence.
关键词：Computer Science - Logic in Computer Science; F.1.2; F.3.2
