Goal Relationships in Blackboard Architectures

HOW CAN WE ENSURE THAT SYSTEMS EMPLOYING A BLACKBOARD ARCHITECTURE MAKE APPROPRIATE FOCUS-OF-CONTROL DECISIONS? THIS IS A COMPLEX PROBLEM REQUIR- ING THE SYSTEM TO RELATE THE PREDICTED RESULTS OF FUTURE ACTIVITIES TO EXISTING HYPOTHESES AND TO STIMULATE ACTIVITIES ALONG PROMISING PROBLEM SOLVING PATHS WHILE INHIBITING ACTIVITIES FOUND TO BE REDUNDANT. THIS PAPER SHOWS THAT MECHANISMS FOR ACHIEVING THESE CAPABILITIES CAN BE INTRODUCED AS NATURAL EXTENSIONS TO A UNIFED DATA-DIRECTED AND GOAL-DIRECTED CONTROL FRAMEWORK. THESE MECHANISMS ARE BASED ON ADDING NEW `GOAL RELATIONSHIPS'' AND A NEW GOAL TYPE, `INHIBITING-GOAL'', TO THE UNIFIED FRAMEWORK. THESE ADDITIONS IMPROVE THE SYSTEM''S ABILITY TO EVALUATE POTENTIAL ACTIVITIES. WE PROVIDE EXAMPLES DEMONSTRATING THE BENEFITS OF THESE MECHANISMS.