All definitions explained in the SLOR ontology section can coexist
in a neutral concept model. This new model provides a new set of
suitable functionalities on each individual learning object conceptualization.
The flexibility acquired with this new schema pro-vides a new scenario
to store whatever type of information (normalized or no) about a
learning object. If it wished (it depends of learning object creator’s
conceptualiza-tion), besides it will be possible including a new
specification with educative aim.
-- figure 3 --
According figure 3, a learning object author “LO-CREATOR”
creates a learning object, a final user can used the object that
it can be located by means of repository searching capabilities.
Besides a learning object author can be described a learning object
in multiple formats. For example a “SCORM” metadata
record with a table of contents, the types of difference resources,
the navigation sequence, etcetera and on the other hand a LOM metadata
record referred to the same LO can be inserted as well. Therefore
SLOR can hold different metadata descriptions referred to the same
object. This feature provides a new interoperability scenario; external
agents can search and interoperate with learning object metadata
records.
SLOR prototype has been specifically designed for the metadata
learning object creation and management, with aim of integrates
and interoperates among other systems. This prototype provides new
functionalities with regard to currently repositories; it is due
to underlying ontology model and middleware tools for the semantic
web enable the execution of reasoning and inference task on metadata
records stored. The SLOR functionalities are grouped according to
scalability principle:
Metadata Creation: According to the conceptual model previously
established by metadata creator, the learning object creation function
allows inserting a new metadata record through new RLO interface.
The entry fields in the creation form correspond to a given conceptual
model of LO, (LearningObject-LOM in the example in Figure 4). However,
other models –listed in the left hand panel in Figure 4–
could be used for storing metadata in the repository.
-- figure 4 --
There is some information that it can be linked to outward ontology
concepts on SLOR basic model. Figure 5 shows an example of metadata
edition where part of the information in the metadata category coverage
is set to the value Spain, an instance of the TGN-Nation class in
the previously-mentioned TGN ontology, which evokes the concept
of Spain as a country. This scenario gives support to a deep level
of search that allows making complex queries, e.g. retrieving elements
of the baroque period that are situated in Spain.
-- figure 5 --
Semantic Search: This function allows searching instances of concepts
in the ontology model such as retrieving all learning objects marked
as “digital” or those learning objects that have an
educational purpose. Several restrictions can be defined as part
of the searching process. Restrictions allow filtering learning
objects on different criteria (pedagogical, economic, or other),
thus providing a set of results that better accomplishes the end-user
needs.
-- figure 6 --
Browsing capabilities: Learning object browsing is implemented
as an ontology-based seeking interface. The browser’s role
in this model is to allow that any metadata category in LOM (excluding
lifecycle and meta-metadata that are not related to the educational
purposes of the objects) can be used as top guiding criteria. The
ontology terms attached as descriptions are displayed in the browser
(figure 6) , and it is finally the user who has the decision on
their selection. The result of user selection is a query expression
formed by a collection of ontology terms. Queries here are by default
interpreted in a contextual basis, i.e. all the requirements selected
by the user should be matched in the same context of the leaning
object. |