Re: SCAM

See also:

http://lttf.ieee.org/learn_tech/issues/january2003/learn_tech_january2003.pdf

Butler, Mark wrote:

>Team, 
>
>Via google and rdf-ig-irc-scratchpad just came across this
>
>http://scam.sourceforge.net/
>
>What it is
>
>"SCAM is a content archive management system, developed under the
>supervision of the KMR group, in cooperation with the Swedish National
>Agency for Education (Skolverket) and Uppsala Learning Lab. It can be used
>as a web-based portfolio system or as an interoperable content archive. 
>
>High emphasize on portability and flexibility has been made, which in turn
>relies on standardization of both design and implementation. Efforts on this
>subject have been one of main challenges during the development. Standards
>involve metadata vocabularies, content packaging, authentication of users
>and access control, system interfaces, etc. 
>
>SCAM is entirely implemented in Java using the J2EE architecture as its
>backbone and use RDF as the metadata representation format. Standards
>include for example Dublin Core and IEEE LOM for metadata, and IMS Content
>Packaging for structural information."
>
>About the repository
>
>"SCAM natively incorporates an RDF-binding of IMS Content Packaging as the
>organizational schema. Roughly an IMS Manifest consists of two different
>types of Components: Resources and Items. A Component X in SCAM-sence is a
>subgraph defined as having an URI X as root-node ending with either a
>literal or another URI. This graph can consist of several blank nodes
>(bNodes) in between which are RDFs definition of nodes having no URI.
>Outspoken, this graph is the metadata about X.
>
>An Item is simply a Component being typed as an IMS Item. This little
>differance significantly changes the way the repository treats the
>Component. For instance if you remove an Item, all its sub-items will also
>be removed. It is analogous to when you remove a folder in a filesystem, all
>its sub-folders and files will be removed. In other words, you can compare
>how a filesystem treats files, softlinks and folders to how the repository
>treats Items and Resources. An Item corresponds to a softlink or a folder
>depending on its structure, and a Resource corresponds to a file. Having
>stated that, we can deduce that an Item is a collection of Components or a
>reference to a Resource. A Manifest is a collection of Components assigned
>in a certain context and can therefore be compared to a filesystem account."
>
>Design
>
>"The primary repository implementation by SCAM utilizes the Enterprise
>JavaBean 2.0 (EJB) concept together with a relational database to provide a
>persistent and scalable storage facility. The database can be just about any
>SQL-enabled relational database. 
>
>The business logic has been divided into several EJBs each responsible for a
>specific set of operations. The EJBs are Stateless Session Beans using Bean
>Managed Persistance (BMP). A package developed by HP Labs called Jena is
>used to assist in the RDF-RDB layer. Jena is also used throughout the entire
>SCAM architechture providing an API against RDF. Future refactoring of the
>repository may include replacing Jena with an Entity Bean solution."
>
>regards
>
>Dr Mark H. Butler
>Research Scientist                HP Labs Bristol
>mark-h_butler@hp.com
>Internet: http://www-uk.hpl.hp.com/people/marbut/
>
>  
>

Received on Thursday, 11 September 2003 12:23:55 UTC