Structured Production System (extended abstract)
  In this extended abstract, we propose Structured Production Systems (SPS),
which extend traditional production systems with well-formed syntactic
structures. Due to the richness of structures, structured production systems
significantly enhance the expressive power as well as the flexibility of
production systems, for instance, to handle uncertainty. We show that different
rule application strategies can be reduced into the basic one by utilizing
structures. Also, many fundamental approaches in computer science, including
automata, grammar and logic, can be captured by structured production systems.
