Trong ẩn dụ này, dữ liệu cảm biến liên quan đến những kiến thức ngắn hạn, trong khi kiến thức lâu dài liên quan đến kiến thức thực tế và thủ tục tương đối tĩnh. Bởi vì các mục tiêu của cả hai hệ thống nhận thức nhân tạo sinh học | FIGURE Biologically motivated metaphor for the data fusion process. Within this metaphor sensor data relates to the short-term knowledge while long-term knowledge relates to relatively static factual and procedural knowledge. Because the goal of both biological and artificial situation awareness systems is the development and maintenance of the current relevant perception of the environment the dynamic situation description represents medium-term memory. In both biological and tactical data fusion systems current emphasizes the character of the dynamically changing scene under observation as well as the potentially time-evolving analysis process that could involve interactions among a network of distributed fusion processes. Memory limitations and the critical role medium-term memory plays in both biological and artificial situation awareness systems enables only relevant states to be maintained. Because sensor measurements are inherently information-limited real-world events are often nondeterministic and uncertainties often exist in the reasoning process a disparity between perception and reality must be expected. As illustrated in Figure sensor observables represent short-term declarative knowledge and the situation description represents medium-term declarative knowledge. Templates filters and the like are static declarative knowledge domain knowledge includes both static long-term and dynamic medium-and short-term declarative context knowledge and F represents the fusion process reasoning long-term procedural knowledge. Thus as in biological situation awareness development machine-based approaches require the interaction among short- medium- and long-term declarative knowledge as well as long-term procedural knowledge. Medium-term knowledge tends to be highly perishable while long-term declarative and procedural knowledge is both learned and forgotten much more slowly. With the exception of the difference in the time constants learning of long-term .
