Introduction

The AEGIS platform allows the creation of extended metadata in the form of Linked Data for each of the entities project, dataset and file. The metadata can be used for rich semantic queries and within the AEGIS tools. The metadata is stored in a triplestore and can be accessed via SPARQL or a RESTful API.

• SPARQL: https://platform.aegis-bigdata.eu/hopsworks-api/virtuoso/sparql/
• RESTful API: https://platform.aegis-bigdata.eu/hopsworks-api/aegis-metadata/

Metadata for Projects

• Metadata for a project can be added by clicking on "Extended Metadata" in the main menu of the project:

• After saving a shortcut to the metadata as JSON-LD is available by clicking on the RDF icon:

Metadata for Datasets

• Metadata for a dataset can be added by right-clicking on the dataset and selecting "Extended Metadata":

• Multiple properties for describing the data are available:

• After saving the metadata can be accessed by a single-click on a dataset:

• Title and description of the metadata are getting automatically machine-translated. By changing the language of the platform the corresponding translations are displayed:

Metadata for Files

• Metadata for a file can be added by right-clicking on the file and selecting "Extended Metadata":

• Note: Some properties can be auto-completed. This is done with the help of the LinDa vocabulary management:

• A detailed description of the file can be added:

• The resulting Linked Data looks for example like this:

Additional Information

• Some extended metadata are also added to the search index of the platform and can be accessed there:

• The SPARQL interface allows detailed queries, e.g. return the title of datasets in English:

• The result of the example: