  We propose specific data structures designed to the indexing and retrieval of
information elements in heterogeneous XML data bases. The indexing scheme is
well suited to the management of various contextual searches, expressed either
at a structural level or at an information content level. The approximate
search mechanisms are based on a modified Levenshtein editing distance and
information fusion heuristics. The implementation described highlights the
mixing of structured information presented as field/value instances and free
text elements. The retrieval performances of the proposed approach are
evaluated within the INEX 2005 evaluation campaign. The evaluation results rank
the proposed approach among the best evaluated XML IR systems for the VVCAS
task.
