Abstract
Many defense, homeland security, and commercial security objectives require continuous tracking of mobile entities such as aircraft. The systems that perform these functions produce information products called tracks. A track associates observations with the mobile entity and typically includes position, velocity, and other similar attributes. Military systems have sophisticated tracking and track fusion processes, but lack uniformity in syntactic and semantic content, preventing effective sharing of the information. In other domains of interest, such as seagoing surface ships, dangerous cargo and persons of interest, tracking systems are less mature and have marginal performance. It is now essential that we be able to share information across different tracking systems working in related domains.
To combine information from different sources, we need a flexible framework that can tolerate and exploit data products from those systems, even though these systems employ different representations and embody different assumptions. The most basic assumptions concern what the information is intended to mean (semantics) and how it is intended to be used by a recipient (pragmatics). In accordance with best practices in the technology areas of the semantic web and knowledge representation, we seek to reduce the barriers to efficient sharing of information.
Our approach is to identify a rich semantic model of tracks that can support multiple important functions: (1) represent a wide variety of meanings and support a broad array of pragmatic goals; (2) reduce the time and cost required to implement capabilities to reason about a new, specialized type of track; (3) simplify the understanding and importation of external sources of track information; (4) help operators describe what attributes of tracks they value in performing their tasks; (5) significantly improve our ability to combine multiple sources of track information; (6) provide a stable and evolvable base for key standards and best practices that support information sharing; and (7) improve bandwidth utilization, raising the proportion of communicated information that recipients consider significant, by delivering valued information at the right time (VIRT). This paper describes the proposed rich semantic track model and ongoing efforts to share it widely with appropriate communities of interest.