During the Smart Appliances project we created a reference ontology for the smart appliances domain, called "Smart Appliances REFerence ontology (SAREF)":
We also created ontologies for each semantic asset in the short list (see ontologies below). These ontologies are expressed in RDF/OWL and serialized in Turtle (therefore, the file extension .ttl), which is a compact syntax alternative to RDF/XML. These ontologies can be opened with any ontology editor, such as TopBraid Composer, Protégé and NeOn. Each ontology has a subpage that contains its description and a URL that points to the file in which the ontology is specified.