List<HNode> sortedLeafHNodes = new ArrayList<HNode>();
worksheet.getHeaders().getSortedLeafHNodes(sortedLeafHNodes);
OntModel autoOntology = ModelFactory.createOntologyModel( OntModelSpec.OWL_MEM );
String ns = Namespaces.KARMA;
autoOntology.setNsPrefix("karma", ns);
OntClass topClass = autoOntology.createClass( ns + worksheet.getTitle().replaceAll(" ", "_")); // replace blank spaces with undrscore
for (HNode hNode : sortedLeafHNodes){
DatatypeProperty dp = autoOntology.createDatatypeProperty(ns+hNode.getColumnName().trim().replaceAll(" ", "_"));
dp.addDomain(topClass);
dp.addRange(XSD.xstring);
}