Newqkb is an abbreviation of "New Quaestor Knowledge base".
This node is always available in the Knowledge Browser when you are Knowledge Engineer. It is the standard empty knowledge base you can start adding knowledge to if you have the proper user rights. Moreover, it will always contain the class node "Quaestor parameters" for all standard Quaestor parameters. Furthermore, it will always contain the QKnowledgebaseVersion parameter.