"Interoperability among Knowledge-Building Environments"

Two XML (eXtensible Markup Language) DTDs (Document Type Definitions) have been defined for knowledge-building threaded discussion data: a recursive version and a linked version:

Recursive version

This data format consists of a tree of discussion notes in which each note contains the sub-tree of notes below it embedded within its data structure. This is a convenient format for storing threaded discussions because the structure of relationships among notes is visible in the data. An XML data file in this format can be simply opened in a browser like IE 5 and the indented thread structure is automatically displayed.

recursive DTD

sample data in the recursive DTD format

Linked version

This data format consists of data on individual notes and explicit data on the links among them. This format is necessary to preserve cross-linking or multiple linking that is more complicated than a tree structure. A knowledge base of notes may form a directed acyclical graph with links of various types. Software applications that manage such knowledge must keep track of linking data explicitly.

linked

sample data in the linked DTD format

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This page last modified on August 01, 2003