The list of organization types in VIVO could be extended with :AdministrativeUnit as a sub-class of foaf:Organization. There are already a couple of universities like http://scholars.library.tamu.edu/vivo/display/n78eb517b or https://vivo.ufl.edu/organizations#http://vivo.ufl.edu/ontology/vivo-ufl/AdministrativeUnit%20 which have this class in their local ontology and use it. We also have a similar class in our local ontology. Since there is a need for this class at several institutions, it would be good to have this class in VIVO Core.
This is also issue https://github.com/openrif/vivo-isf-ontology/issues/756