Here you have access to a list of Models that have been shared by users of S3DB. You can either share/download the N3 files, which will have IDs associated with them, of the XML files, which will give you templates for the data models. Feel free to explore the Map of each model before importing.
Files without IDs
If you download a file without IDs, this means that you will import only the template for the Project, but will not replicate the actual project itself. This means that the unique identifiers will not be replicated. This is the more convinient option when you just want a template from which to strat creating your ontology.
Import these files using the button that says "Import from XML" in the Project's main page: