Li Yuan, PhD


Faculty of Science - Computing Science




  • B.S., Electrical Engineering, Shanghai Jiao Tong University (China), 1978
  • M.S., Electrical Engineering, Shanghai Jiao Tong University (China), 1981
  • Ph.D., Computer Science, Case Western Reserve University, 1986



Artificial Intelligence
Database Systems


Logic Programming, Artificial Intelligence, Database Systems.


My research interests include logic programming, artificial intelligence, and database management systems. My current research activities focus on knowledge representation, default reasoning, disjunctive program semantics, and concurrency control of object relational database management systems.

My recent work on default reasoning investigates the relationship between negative introspection and the expressive power of autoepistemic logic. I demonstrate that a classical modal logic augmented with a new introspection rule is capable of characterizing almost all default reasoning semantics.

The study of theoretical foundations of disjunctive logic programs with default negation has attracted considerable attention. One of my research objectives in this area is to use Kripke structures of autoepistemic logic as a tool to classify disjunctive program semantics.

My research in the area of database management systems involves the use of logic programming with negation as a framework for modeling nested and multi-level transactions as well as implementing concurrency control schemas for object relational database systems.