SDL and the semantic web initiave
The development of the Semantic Web (SW) in an Organization requires not only the development of specific technologies of the SW layers stack, but also the adoption of specific technical policies, by the hosting Organization:
- The definition of the structural composition of the SDL's digital resources
- The definition of an identifiers system for identifying the SDL's resources with "good URI"s.
- The definition of a profile, the SDL MODS profile. for descriptive metadata based on Metadata Object Descriptive Schema(MODS) an XML standard
Starting from the SDL MODS elements and vocabularies defined in the profile, has been defined the SDL semantic model for descriptive metadata as conceptual reference model for the future implementation of the SW technologies, in the SDL knowledge domain.
The SW is a set of layered technologies that allow to give substance to the Tim Berners-Lee's vision.
The data, matching the requirements of the following four rules (Berners-Lee, 2006), can be considered Linked Data:
- Use URIs as names for things
- Use HTTP URIs so that people can look up those names
- When someone looks up a URI, provide useful information, using the standards (RDF*, SPARQL)
- Include links to other URIs, so that they can discover more things
The SDL has taken the W3C Best Practices for Publishing Linked Data into account. Hereafter, the best practices are summarized, followed by the current status of the SDL:
| W3C Best Practices' steps | Local status |
|---|---|
| PREPARE STAKEHOLDERS: | stakeholders of SDL'resources are informed when they provide digital objects to the SDL. |
| SELECT A DATASET | at this time Sapienza's libraries dataset is already accessible over the web, and is used for the SDL's digital resources. |
| MODEL THE DATA - Modeling LD involves representing data objects and how they are related in an application-independent way. | the SDL digital resources were modelled for the Web and looking after their Semantic Web re-use. |
| SPECIFY AN APPROPRIATE LICENSE | all descriptive metadata of SDL digital resources openly published in the current version(2013) are under the Creative Commons Attribuzione 3.0 Italia (CC BY 3.0 IT). |
| GOOD URIs FOR Linked Data | currently used for the content pages of SDL's resources, and the SDL local controlled vocabularies. |
| USE STANDARD VOCABULARIES | whenever possible we have used existing vocabularies and we have developed local vocabularies when at the best of our effort we couldn't find exhaustive similar vocabularies. Currently they are provided as RDF data dump at sbs.uniroma1.it/vocabulary. |
| CONVERT DATA - Convert data to a LD representation. This is typically done by script or other automated processes. | currently we use an automatic mapping for serializing MODS XML the provision of related RDF data is under development. |
| PROVIDE MACHINE ACCESS TO DATA | at this moment all SDL digital resources are indexed by search engines and accessed by HTTP URIs. |
| ANNOUNCE NEW DATA SETS - Remember to announce new data sets on an authoritative domain. | once the development and test is completed, it will be announced. |
| RECOGNIZE THE SOCIAL CONTRACT - Recognize your responsibility in maintaining data once it is published. | to be defined. |