KR, constraint-based knowledge representation

KR is a very efficient knowledge representation language implemented in Common Lisp. It provides powerful frame-based knowledge representation with user-defined inheritance and relations, and an integrated object-oriented programming system. In addition, the system supports a constraint maintenance mechanism which allows any value to be computed from a combination of other values. KR is simple and compact and does not include some of the more complex functionality often found in other knowledge representation systems. Because of its simplicity, however, it is highly optimized and offers good performance. These qualities make it suitable for many applications that require a mixture of good performance and flexible knowledge representation. This research was sponsored by the Defense Advanced Research Projects Agency (DOD), ARPA Order No. 4976, Amendment 20, under contract F33615-87-C-1499, monitored by the Avionics Laboratory, Air Force Wright Aeronautical Laboratories, Aeronautical Systems Division (AFSC), Wright-Patterson AFB, Ohio 45433-6543. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the official policies, either expressed or implied, of the Defense Advanced Research Projects Agency or the US Government. Table of