Abstract: A system and method for rapidly obtaining information about the suitability of terrain to meet concealment or visibility objectives, such as might be needed for military planning or for determining placement of relay antennas in a cellular communication system, is disclosed. The disclosed system precomputes heuristic visibility fields for a geographic area, then uses the precomputed heuristic visibility fields to rapidly determine points on a map that will provide the desired characteristics of exposure or concealment in response to a query.

Abstract: A knowledge-based system (10) which combines case-based reasoning, heuristic search and deductive rule application. The resulting inference engine is sensitive to the context of problem solving. The system (10) includes a heuristic searcher (22), a case memory (14), a rule memory (18), a rule applier (26) and a case matcher (24). The rule applier (26) uses stored rules to elaborate on new cases by deriving new features so that it will be closer to selected old cases. The case matcher (24) detects how close selected cases are to the new case and generates a score for the match. The heuristic searcher (22) maintains a plurality of elaborated cases and determines the goodness of each elaborated case, the goodness being a measure of the match between the elaborated case and the selected old case.