Extending DLR with Labelled Tuples, Projections, Functional Dependencies
  and Objectification (full version)
  We introduce an extension of the n-ary description logic DLR to deal with
attribute-labelled tuples (generalising the positional notation), with
arbitrary projections of relations (inclusion dependencies), generic functional
dependencies and with global and local objectification (reifying relations or
their projections). We show how a simple syntactic condition on the appearance
of projections and functional dependencies in a knowledge base makes the
language decidable without increasing the computational complexity of the basic
DLR language.
