Below
Shitao Li:
OASIS TOSCA has provided the latest explaination for namespace convention last week. For your interesting, you can download the document with the below link for more details.
2017-11-02 - TOSCA Namespacing Explained - Draft.pptx (https://www.oasis-open.org/committees/document.php?document_id=61935&wg_abbrev=tosca)