========================================================
The given Problem was:
a a b b -> b b b b b a a a a a 
========================================================
A self-embedding rewrite structure for the given SRS is:
   a a b b b b --(2)-> b b b b b a a a b b b b b a a a a a (#2)
   OC+OC at 8
      OC: a a b b --(1)-> b b b b b a a a a a (#1)
          Rule
      OC: a a b b --(1)-> b b b b b a a a a a (#1)
          Rule
Hence, the SRS is non-terminating.