This is the target for the CellML 1.1 namespace prefix. Currently there is nothing useful here. As the specification is developed, documentation on each of the elements and attributes in the CellML namespace will be added.
In the meantime, why not have a poke around the CellML website at
Note that a namespace URI provides a unique identifier for a particular dictionary of CellML elements. It need not link to a schema or DTD.
