Information Technology Reference
In-Depth Information
option to grant others with privileges for copying
and changing learning units owned by them. The
next level is the presentation of this material. In
order to support reuse of LO, Diplek permits ac-
cess to all material in the system database, even
the one that has been created by other instructors
(as long as the creator permits it). As said before,
this material can be of any type and any size as
long as it keeps up with the database storage re-
quirements (amount of data each user can store).
These requirements or limitations are defined by
the system administrator.
As the available educational resources grow
larger each day, the need for extra information
becomes obvious. The lack of information about
the location, properties, educational context or
availability of a resource could make it difficult
to use. Metadata contributes to solve this problem
by providing a standard and resourceful way to
conveniently characterize resource properties. In
this way, instructors with not much experience in
using learning management systems can find the
Learning Object they are looking for by describ-
ing some of its properties.
The radical development of LMSs and the
use of metadata to describe Learning Objects
brought up the need for metadata standardization
so as to enable reuse and interoperation among
heterogeneous platforms. To accomplish this, an
agreement is needed on architectures, services,
protocols and open interfaces.
Several initiatives took place aiming to deliver
a standard set of metadata that would describe
a Learning Object, such as the IEEE Learning
Object Metadata (LOM) (Edvardsen & Sølvberg,
2007) and the Dublin Core Metadata Element set
for education (DC) (Baker, 2005).
LOM specifies the syntax and semantics of
learning object metadata, defined as the attributes
required to fully and adequately describing a
Learning Object. This includes element names,
definitions, data types, vocabularies, and field
lengths. LOM is focused on the minimal set of
attributes needed to allow these Learning Objects
to be managed, located and evaluated. Related
attributes of Learning Objects to be described
include author, type of object, terms of distribution,
owner and format. Where appropriate, learning
object metadata may also include pedagogical
attributes, such as teaching or interaction style,
grade level, level of difficulty, and prerequisites.
The Dublin Core Metadata Element Set (Baker,
2005) is a general-purpose and widely adopted
metadata scheme targeted to resource location
developed within the Dublin Core Metadata
Initiative. It is compact and its elements are the
result of a wide consensus. The DC-Education is
a Working Group that was formed to develop and
make a proposal for the use of Dublin Core meta-
data for the description of educational resources.
Essentially, its task is to propose extensions to
the DC metadata set to describe these kinds of
resources, taking LOM and the IMS Global Learn-
ing Consortium proposal as a basis.
Diplek uses the IEEE LOM standard for its
learning object repository. The reason for choos-
ing LOM among many other well defined and
documented standards is that it fully describes both
Data to Describe Learning
Objects (Metadata)
The capability to associate metadata with LO
makes Diplek a powerful tool for easy search and
indexing. Metadata (Jing, Li & Fang, 2005) are
conventionally defined as data which is used to
describe data and it provides a means to describe
the information of learning objects. Metadata are
used to describe document contents and structure,
and to provide information about accessibility, or-
ganization of data, relations among data items, and
the properties of the corresponding data domains.
However, metadata can also be used to provide
descriptions for non-textual objects, like images,
videos and sounds. Nowadays, hundreds of col-
lections worldwide already adopted metadata as
the basic tool for information representation and
cataloguing.
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