The Asset Description Metadata Schema was originally created under the EU's ISA Programme and was published on its Joinup platform.
The current Editor's Draft includes this description of ADMS (which is, of course, subject to change)
It is a vocabulary for describing so-called Semantic Assets, that is, things like standards, code lists and taxonomies. Although it has a lot in common with DCAT, notably the extensive use of Dublin Core, someone searching for a Semantic Asset is likely to have different needs, priorities and expectations than someone searching for a data set and these differences are reflected in ADMS. In particular, users seeking a Semantic Asset are likely to be searching for 'a document' — something they can open and read using familiar desktop software, as opposed to something that needs to be processed. Of course this is a very broad generalization. If a code list is published as a SKOS Concept scheme then it is both a Semantic Asset and a dataset and it can be argued that all Semantic Assets are datasets. Therefore the difference in user expectation is at the heart of what distinguishes ADMS from DCAT.
Joinup keeps a track of a list of implementations of ADMS on this page
The overlap between ADMS and DCAT is a key discussion point.
20 march 2013
I have created a new diagram for ADMS for discussion. It does away with RADion and is now very close to DCAT. So much so that it might be considered as a DCAT profile? Perhaps adms:SemanticAssetRepository etc. could be sub classes of their DCAT equivalents?
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