  Matchmaking and information ranking are helping process for users, by
offering them the best answers possible at their request. When there is no
exact answer, giving them the closest proposition available is an efficient
upgrade of that helping process. With a reasearch platform on metrology as a
framework, we will discuss about ranking with knowledge representation, with an
approach based on Description Logic, ontologies and multricriteria comparison.
We present a reasonning to compare each proposition with the other, with
semantic and syntaxic difference, by troncating the information in distinct
component.
