Sharedresources Metadata

The Sharedresource system provides a full metadata based index for resources. This documentation explains how to setup the metadata system, and some reminders about those models.

What Are Metadata

Metadata ae piece of information that are NOT the content of the indexed object, but some information ABOUT this object that need to be stored aside. Metadata could be simple flat list of attributes, f.e. for an image, an explicit mention of its size in pixel, color model, authoring tool origine etc.

This metadata are quite usefull to help people searching for an adequate resource, if they are carefully initialized.

As long as metadata were used more and more, the number of attributes increased, and simple flat lists were a bit complicated to work with. So metadata came to be organized in a hierarchy, with chapters and subchapters. Thus metadata came to be stored as hierarchic schemas.

Dublin Core

Dublin Core is a generic technique to organize such information storage. What is essentially needed to be retained is that Dublin Core requires that each piece of information is to be stored as a "tree node" with an numeric index of the node made with each local node count (from 1) of all branches in the path to the root. Nodes are thus numbered 1, 1.1, 1.1.1, 1.1.2, 1.2, etc.

Each node can be a single value or a list of values. The schema will tell for each if a list or a scalar. When a node admits a list, all items of the list will still be identified by the same DC node index. (f.e. multiple keywords attached to a ressource will be multiple value items of the node 1.5)

Each node value or item value can be :

• some explicit format compliant value (f.e. a date)
• some vocabulary entry (one of a set of finite non mutable set of terms)
• a free input value

LOM

Standing for Learning Object Metadata, this is a Dublin Core compliant standard for describing learning resources of many types. The standard proned to be generic and international. The LOM opens 9 first level categories for storing metadata pieces of information.

Category 1 is "General information" while

Category 9 is related to "Classification".

LOM proposed a strict definition of vocabularies for some metadata entries such as "document type", with some possible caveheat that the initial set of terms being not able to follow the evolution of the surrounding technologic or practical environment.

LOM Extensions and Derivatives

As far as metadata being accepted by the pedagogic community, the initial schemes could not comply with the real field practices. The resource description needs were evolving and the standard did not clearly separate the semantic identification from the idiomatic environment.

Several countries provided they own extension, as admitted by the standard.

F.e. in France, a first LOM derivation was opened as LOMFRv1.0, taking the occasion to adapt and complete a few vocabularies. Then came requirements of the National French Education system, needing to precise some resource specifications related to the interaction of the resource with the organisation of education system in France. This came to the ScoLOMFRv1.0 standard. A third standard appear when french higher education examined the ScoLOMFR and decided some choice were NOT adapted to their environment. So the SupLOMFRv1.0 was established.

Other countries have similar standard progress.