SEARCH STRATEGIES WHICH CAN BE CONTINUOUSLY MODIFIED WERE DEVELOPED FOR COORDINATE SEARCHING SYSTEMS. USING THE FILES OF THE NASA TECHNOLOGY UTILIZATION PROGRAM AT THE KNOWLEDGE AVAILABILITY SYSTEMS CENTER, UNIVERSITY OF PITTSBURGH, A STUDY WAS CONDUCTED OF THE RETRIEVAL OF RELEVANT DOCUMENTS BY BOTH MANUAL AND MACHINE METHODS FOR FIVE QUESTIONS IN THE AREA OF INSTRUMENTATION. BECAUSE THE RATE OF RETRIEVAL OF ACCEPTABLE (OR RELEVANT) DOCUMENTS WAS SO LOW AND THE RATE OF RETRIEVAL OF NON-RELEVANT DOCUMENTS SO HIGH, A SEARCH STRATEGY BASED UPON CONTINUAL MODIFICATION WAS FORMULATED. TWO TABLES WERE MADE, ONE OF ALL THE KEYWORDS USED TO INDEX EACH RELEVANT DOCUMENT FOR A PARTICULAR QUESTION, AND ONE OF THE KEYWORDS FOR THE NON-RELEVANT DOCUMENTS. KEYWORDS WERE THEN ELIMINATED FROM THE ORIGINAL SEARCH STRATEGIES IF THEY WERE NOT COMMON TO THE RETRIEVED RELEVANT DOCUMENTS. TERMS WERE ADDED TO THE ORIGINAL SEARCH STRATEGY IF THEY WERE COMMON TO SEVERAL RELEVANT DOCUMENTS, BUT NOT COMMON TO NON-RELEVANT DOCUMENTS. A COMPARISON WAS THEN MADE OF THE NUMBER OF RELEVANT AND NON-RELEVANT DOCUMENTS RETRIEVED BY THE REVISED SEARCH STRATEGIES AND THE ORIGINAL SEARCH STRATEGIES FOR A NEW SET OF DOCUMENTS. THE REVISED SEARCH STRATEGIES DID NOT HAVE AN OVERALL EFFECT ON THE NUMBER OF RELEVANT DOCUMENTS, BUT THE NUMBER OF NON-RELEVANT DOCUMENTS RETRIEVED WAS REDUCED 57 PERCENT. IN GENERAL, THE SYSTEM REDUCES THE "NOISE" IN AN INFORMATION SYSTEM AND INCREASES THE PERCENTAGE OF RELEVANT DOCUMENTS WITH CERTAIN CONSTRAINTS. THIS DOCUMENT ALSO CONTAINS AN EXPLANATION OF THE NASA TECHNOLOGY UTILIZATION PROGRAM AND ITS FILE FORMATS AS USED AT THE KNOWLEDGE AVAILABILITY CENTER. IT IS AVAILABLE AS AD-481-441 FROM THE CLEARINGHOUSE FOR FEDERAL SCIENTIFIC AND TECHNICAL INFORMATION, SPRINGFIELD, VIRGINIA 22151, $3.00 FOR HARD COPY, $0.65 FOR MICROFICHE, 514 PAGES. (CM)