OwlEd supports standard inference
services of DL reasoners, namely
subsumption, satisfiability, equivalence
and disjointness for concept expressions,
instance checking, retrieval and
realization. Furthermore, as its design
has been specifically oriented towards
semantic matchmaking services it also
features nonstandard services supported by MaMaStng.
Such services are hereafter briefly
described.

Match type
detection. Given an ontology
T, it allows to determine the match
category between a request D and a
resource S. In particular, matches
are classified within the following
categories, which have been defined
sometimes with different names by
various authors:

exact match

full match

plugin match

potential match

partial match

Rank Potential.
Given an ontology Tand two concept
expressions representing a request
D(for demand) and the resource S to
be matched with D, both satisfiable
with respect to T. If D is compatible
with S  Potential Match, i.e., their
conjunction is satisfiable with
respect to T  then Rank Potential
returns a score measuring the
semantic distance of S from D (D is
classified with respect to S) taking
into account the information modeled
in T.

Rank Partial. Given
an ontology T and two concept
expressions representing a request D
(for Demand) and the resource S to be
matched with D, both satisfiable with
respect to T. If Dis NOT compatible
with S  Partial Match, i.e., their
conjunction is NOT satisfiable with
respect to T  then Rank Partial
returns a score measuring the
semantic incompatibility of D and S.

Concept Abduction.
Given an ontology Tand two concept
expressions representing a request D
(for Demand) and the resource S to be
matched with D, both satisfiable with
respect to T. If Dis compatible with
S  Potential/Full/Exact Match  with
Concept Abduction it is possible to
compute a concept expression H
representing what is underspecified
in S in order to completely satisfy D
 S is classified by D with respect
to T  taking into account the
information modeled in T. In other
words, H represents an explanation on
why S is not classified by D with
respect to T. Notice that rank
potential can be used as a numerical
measure of H for the related Concept
Abduction Problem.
In Figure 3 results to requests of
Concept Abduction are depicted, in
case of Potential match (Request
ID:10) and Full match (Request
ID:11). In the former case, an
explanation hypothesis of what is
missed in S (Supply) in order to
completely satisfy  be more specific
than  D(Demand) is computed. In the
latter case, no explanation is
provided because a Full match occurs.

Concept Contraction.
Given an ontology Tand two concept
expressions representing a request D
(for Demand) and the resource S to be
matched with D, both satisfiable with
respect to T. If Dis NOT compatible
with S Partial Match  then with
Concept Contraction it is possible to
compute a contraction K (for Keep) of
D which is compatible with §
taking into account the information
modeled in T. The solution computed
for the Concept Contraction problem
is a pair of concept expressions G
(for Give up) and K (for Keep) whose
conjunction is equivalent to S with
respect to T. In other words, G
represents an explanation on what in
Dis not compatible with S (causing a
Partial Match). In Figure 4, an
example of Concept Contraction is
depicted.

Concept Covering.
Given an ontology T, a concept
expressions representing a request
D(for Demand) and a set of resources
R = {R_{i}} all satisifiable
with respect to T. Find a subset of R
such that the conjunction of all the
elements in such subset is both
satisfiable with respect to Tand is
more specific than D. If the
conjunction is not more specific than
D  Potential Match  the
remaining/uncovered part of D is also
returned. A Concept Covering, can be
performed either allowing to contract
D  Extended Concept
Covering  or not  Basic
Concept Covering.
