414 Chapter 17 Planning Based on Model Checking
Strong-Cyclic-Plan is guaranteed to terminate, it is sound (i.e., the returned
policies are strong cyclic solutions), and it is complete (i.e., if it returns failure,
then there exists no strong cyclic solution). It corresponds to the computation of
a greatest fixed point where states are removed when not needed (while strong and
weak planning correspond to the computation of a least fixed point).
We conclude this section with two remarks. First, for the sake of simplicity, we
have described weak, strong, and strong cyclic solutions in terms of properties of a
graph representing the executions of a plan. In Section 17.3, we will show how these
solutions can be expressed as formulas in temporal logic and ...