Semantic Engine
The ISS Semantic Engine provides the core intelligence required to transform published XML data to and from Information Objects and to manage their distribution to satisfy the active information subscriptions. The Semantic Engine maintains the I3 Semantic Repository and the ISS Metadata. The Semantic Engine API provides two categories of functionality: Metadata Management, and Information Processing.
Metadata Management
Both I3 Metadata and ISS Metadata are managed through the Semantic Engine. I3 Metadata is contained in the Semantic Repository and defines the semantic
relationships required for information exchange. The ISS Metadata is stored separately and fully describes the information sources, subscriptions, and users who are serviced by the Information Sharing System. Metadata Management allows the continuing expansion and refinement of the I3 Metadata as the enterprise semantic base grows, and
provides for the addition, deletion, modification, activation, or suspension of ISS Metadata definitions controlling information flow.
Information Processing
Information
Processing functions start with basic transformation from "local" XML data packages to universal Information Objects. These transformations operate
from metadata "maps" that define the substitutions necessary to generate an Information Object from XML and the reverse. Once the Information Object has been created, it is manipulated by the more advanced information
processing functions in order to match the information to the contexts defined in subscriptions and distributions. Advanced information processing functions provided by the ISS are of two types: Information Object Algebra, and
Intelligent Agents.
Information Object Algebra
The hierarchical structure of Information Objects and the selection of their XML Tags from the I3 Semantic Repository allow these
objects to be manipulated "mechanically" to produce derivative Information Objects that have valid and appropriate meaning. Some of these manipulations operate upon the Information Object XML alone, while others require
access to the I3 Semantic Repository as well. Information Algebra Functions provided by the ISS include Normalization, Generalization, Rotation, Filtering, Addition, and Subtraction.
Intelligent Agents
The power of the Semantic Engine is further enhanced through the use of Intelligent Agents to manage specific classes of Information Objects. Each instance of an Information Object employs tags from the I3SR that
fully define the meaning of its data content. The Intelligent Agent examines the information explicitly provided as "physical" data in the object and produces all of the useful derivative information elements requested by
correspondent processes. Th resulting “intelligent” Information Objects can be visualized as always containing a complete set of the relevant information content. The Intelligent Agent supports update to a derived element by
cascading the change to the corresponding physical data elements. This approach means that the work required to deal with the many variations of format and content are removed from the applications and are provided by the Information
Object directly. Examples of Intelligent Agents provided by the Semantic Engine are PersonName and PostalAddress. Intelligent Agents are being added to the Semantic Engine library continuously. Information Sharing System
users are encouraged to develop their expert application functions as Intelligent Agents so they may be licensed to other ISS users.