Standards and Specifications
The following list indicates the standards and specifications that ASPECT focused on at the start of the project in September 2008 and the status regarding how ASPECT had addressed each of them by the end of the project in March 2011.
The Learning Object Discovery & Exchange (LODE) specification aims to facilitate the discovery and retrieval of learning objects stored across more than one collection. It can be seen as a ‘glue’ specification in that it profiles existing general-purpose protocols in order to take into account requirements specific to the educational domain, rather than attempt to create new protocols. It proposes three main data models:
- A LODE Context Set for the Contextual Query Language (CQL): a data model for the attributes of learning objects, which can be used for search by expressing educationally meaningful queries;
- A data model, named Information for Learning Object eXchange (ILOX), that organizes sets of metadata on learning objects to be used in data exchange; and
- A data model, named Learning Object Repository Registry Data Model, for learning object collections, to be used in discovering and configuring access to those collections.
IMS LODE is a direct result of the ASPECT work on metadata and registries and the project’s collaboration with other international groups on these topics. ASPECT partners have made their content available through ILOX and the ASPECT registries are based on the LODE registry data model.
IEEE LOM Dublin Core
IEEE LOM and Dublin Core were well adopted at the start of the project. DC is for content in general while LOM is designed for educational content. The major need was to be able to transform metadata instances from one format into another. While solutions for mapping the default specifications existed, good solutions were lacking for specific application profiles of IEEE LOM and DC.
The LRE metadata application profile implemented by the ASPECT partners combined IMS ILOX with LOM.
VDEX, ZTHES, SKOS
At the start of the project, ZThes and VDEX had a wide adoption. SKOS had currently the best approach to the mapping of vocabularies. Hence, it was thought that transformers between the formats should be offered to the wider audience of vocabulary developers. However, this was not seen as sufficient. All too often it is the case that Application Profile developers invent vocabularies again and again. Apart from being inefficient, it harms the semantic interoperability of different application profiles. Given this situation, it was thought that adoption could be best supported by providing a registry for vocabularies and mappings between vocabularies that allows for uploading and downloading in different formats.
ASPECT has adopted VDEX, ZTHES and SKOS as input and output formats of the Vocabulary Bank for Education (part of the LRE Service Centre provided by ASPECT). The XML bindings developed by ASPECT rely on external controlled vocabularies stored in these formats. ASPECT has also developed validation tools that take advantages of these external vocabularies.
SQI, SPI, SRU/SRW, OAI-PMH
At the start of the project, SRU/SRW were well adopted in the library world. SQI had a good adoption in the European Learning Technology world and many MoEs had adopted it for exchanging LOM instances in the LRE. SQI had been developed in order to support more advanced features such as asynchronous communication and different query languages in federated LOR networks. The project started with the belief that SQI could be profiled to support SRU/SRW such that both specifications could be used in a federated search scenario. OAI-PMH was well adopted also in the European LT world. As it was dealing with a different scenario (harvesting), it was thought that it could co-exist with the other specifications. SPI was at the specification stage. It was work planned under a CEN/ISSS contract.
ASPECT efforts have concentrated on the use of OAI-PMH as the main way to feed the LRE with metadata. All the ASPECT content providers have adopted this protocol. In addition, ASPECT has contributed to the development of the SPI specification and tested it as a way to push metadata in a repository towards other stakeholders, as opposed to OAI-PMH that is used by other stakeholders to pull metadata out of a repository.
CQL, PLQL, LRE-QL
At the start of the project, these were all abstract query languages that operated on a conceptual model instead of, for instance, relational tables. They had been developed by different parties involved in federating LO repositories and were used to interrogate metadata following the IEEE LOM. It was thought that it would be better to have a single well thought through query language.
ASPECT work on query languages was limited. This reflects the preference given to metadata harvesting over federated searches to build federations of learning object repositories. ASPECT’s main contribution in this field is the LODE context set that makes it possible to simplify the expression of educationally meaningful queries in both CQL and PLQL.
SCORM, IMS Common Cartridge, IMS Content packaging
In Europe at the start of the project SCORM had been well adopted in training military personnel and to a large extent by commercial publishers, also especially for training purposes. However, the adoption in the school sector was limited. Cited barriers included the limited pedagogical models (primarily instructional design) that SCORM supports, as well as the steep learning curve demanded if users wished to repurpose a SCO, a situation that occurs much more frequently in the school sector.
ASPECT has contributed to the development of the IMS Common Cartridge specification. It encompasses Content Packaging, Question & Test Interoperability (QTI) and IEEE LOM. Icodeon, an ASPECT partner and a member of IMS, made available a Common Cartridge RESTful Web Services Platform that was used by project partners.
ASPECT did not address the barriers to SCORM take-up, as this would have involved a long-term effort within the Learning Technology research and pedagogical communities. However, ASPECT helped content providers to use SCORM as well as to apply Common Cartridge to learning resources and tested both specifications with teachers in a small-scale pilot involving 40 teachers in four countries. This findings from this practical experimentation go some way towards confirming the view that SCORM is more suitable for self-paced learning while Common Cartridge may be more appropriate for blended learning scenarios (i.e., mixing traditional teaching in the class-room with e-learning). However, given the limited size of this experiment, these initial results need to be confirmed by larger and more wide-ranging study that is beyond the scope of the project.
At the start of the project, IMS-QTI was reasonably well adopted and worked well for what it was supposed to do. While the consortium recognized at the start of the project that the educational world needed more advanced specifications to fully support assessment, this was not retained as an ASPECT objective.
ASPECT helped content providers to use IMS-QTI mainly both as a stand-alone specification and as part of the IMS Common Cartridge specification.