QNT classification scheme presents a new approach to the construction
of general persistent polyhierarchical classifications.
we mean a set of categories partially ordered by relation "is a" where every
element can have more than one parent (a non-tree hierarchy).
QNT classification is based on implicit description of category polyhierarchy
by a compact generating polyhierarchy of classification criteria. Similarly to existing approaches, the classification categories
are defined by logical functions encoded by attributive expressions. But unlike other methods, our classification technique provides
inherently flexible definition of domains of criteria applicability, and the semantics of relations between categories is invariant to
changes in the universe composition, extending variety of criteria and increasing their cardinalities.
To view a Powerpoint presentation outlining the approach and its benefits,
click here (824 Kb).
A formal description of the QNT classification scheme has been published at
To read a comprehensive popular description,
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