The OSCAF ontologies derive from the contributions to a number of large-scale efforts, starting with the European project NEPOMUK (2006-2008), continuing with their adoption (and extension) by the KDE community (2009-2013), and their further extension by a second European project Digital.Me (2010-2013).
NOTE: Specifications of all OSCAF ontologies and their versions are maintained. Accessing the specifications of an ontology below will lead you to the latest version, but earlier versions are accessible. Each version is persisted separately, and is marked by one or more of the NEPOMUK, KDE or Digital.Me logos (as shown at the top of this page) to denote the context of that version's application
The NEPOMUK project sought to realise a Social Semantic Desktop. This vision proposed a user's personal information environment as a source and end-point of the Semantic Web: Knowledge workers comprehensively express their information and data with respect to their own conceptualisations. Semantic Web languages and protocols are used to formalize these conceptualisations and for coordinating local and global information access. The Resource Description Framework RDF serves as a common data representation format. Nepomuk identified several additional requirements for high-level knowledge representation on the social semantic desktop. With a particular focus on addressing certain limitations of RDF, a novel representational language akin to RDF and the Web Ontology Language OWL was engineered. Various other high-level ontologies were then provided, covering several aspects of concepts and information elements a desktop user frequently encounters. Together, they provide a means to build the semantic bridges necessary for data exchange and application integration on distributed social semantic desktops.
Although designed to fulfill requirements for NEPOMUK, the first set of OSCAF ontologies were applied by other parties and communities. In particular, the KDE community used and further developed the ontologies for the classification, organisation and presentation of data. KDE-Nepomuk was not provided as an application, but as a component which can be used by developers within applications. Four new ontologies (NSO, NMM, NUAO, NDO) were introduced to OSCAF during these developments.
After 2009, reacting to a popular shift to an ubiquitous personal workspace brought on by an increase in smart and mobile devices, OSCAF ontologies were this time extended to move away from the desktop as the singular personal data source. The Digital.Me project introduced the concept of a personal information sphere, referring to multiple devices (including personal computers, tablets and smartphones) and also remote Web services and online accounts as holders of personal information. In view of the need to integrate and better manage this distributed personal data, a number of extensions to existing ontologies, plus a number of new ontologies have been submitted and published by OSCAF. These include coverage not only of new and yet 'traditional' personal information that is of direct interest to the user (DLPO - for online item sharing), on more than one device (DDO) and online accounts (DAO), but also of context/presence-related information (DCON, DPO), privacy preferences, user histories (DUHO) as well as ontologies for the personalisation and customisation of entire systems and automised events (DRMO).
The specifications for published OSCAF Ontologies can be accessed below. In order to orient the readers with the purpose and relationships between the ontologies, we depict the ontologies in a top-down pyramid structure. NRL extends RDF/S. In the upper-level layer, NAO provides for generic annotation, whereas the rest of the ontologies are more domain-oriented. The NIE Ontology Framework consists of several sub-ontologies. The PIMO Ontology deals with objects that are handled directly by the user. This is denoted by the white-edged inset pyramid. Lower-level ontologies are not provided by OSCAF. However, there have been a number of such ontologies based on the OSCAF ontologies, to target specific domain knowledge.