### Duration Calculus and its Treatment for Continuous Time

**Prof. Zhou Chaochen**

United Nations University/IIST
Macau
The Duration Calculus (abbreviated DC)
represents a logical approach to formal design
of real-time systems. DC is based on interval logic, and
uses the real numbers to model continuous time, and
Boolean-valued (i.e. {0,1}-valued) functions over time to
model states and events of real-time systems. The duration
of a state in a time interval is the accumulated presence
time of the state in the interval. DC extends interval logic
with a calculus to specify and reason about properties of state durations.
This talk will give a brief introduction to DC, and explain how DC keeps the
essence of discrete time when it adopts continuous time, so that continuous
time becomes tractable in terms of computing science. The explanation will
refer to the induction rules of DC, its model checking tool and its
application to real-time programming.