Semantic Web

From ActiveArchives

This page is currently being worked on.

The development of the Active Archives project is informed by concepts of the Semantic Web, and in particular the implementation of the Semantic MediaWiki extension. This page contains some working notes on concepts related to the Semantic Web.

RDF

Resource Description Framework [1]

OWL

OWL = Web Ontology Language

OWL supportes inference, and there are a number of software "reasoners" available to work with OWL data. [2].

OWL adds a number of important aspects to RDF. One is that:

OWL uses the linking provided by RDF to allow ontologies to be distributed across systems. [3]

Also, interestingly is the notion of being accumulative, and purely additive (much as a wiki page accumulates it's changes, never actually deleting anything).

In addition, OWL makes an open world assumption. That is, descriptions of resources are not confined to a single file or scope. While class C1 may be defined originally in ontology O1, it can be extended in other ontologies. The consequences of these additional propositions about C1 are monotonic. New information cannot retract previous information. New information can be contradictory, but facts and entailments can only be added, never deleted. [4]

Also interesting, with respect to supporting systems for bridging between different organizations / ontologies, are the mechanisms for linking different concepts as being the same (or different). OWL defines a sameAs [5] relation to indicate two individuals are to be considered the same, and a equivalentClass, and equivalentProperty' is used for classes and properties. [6]