The vision of the Social Semantic
Desktop defines 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 conceptualizations. Semantic Web languages and protocols are
used to formalize these conceptualizations and for coordinating local
and global information access. The Resource Description Framework
RDF serves as a common data representation format. We identified
several additional requirements for high-level knowledge representation
on the social semantic desktop. With a particular focus on addressing
certain limitations of RDF, we engineered a novel representational
language akin to RDF and the Web Ontology Language
OWL, plus a number of other high-level ontologies.
Together, they provide a means to build the semantic bridges necessary for data
exchange and application integration on distributed social semantic desktops.
Although initially designed to fulfill requirements for the
NEPOMUK project, these ontologies are useful for the semantic web community in
The specifications for the following published NEPOMUK Ontologies
are given below.
- NRL - NRL is NEPOMUK's Representational Language. Designed
on top of RDF, it addresses certain limitations on the part of RDF/S.
In particular it includes support for Named Graphs, which although
being a widely-popular notion, have not been supported by any
representational language so far. It is also based on a view
concept for the tailoring of ontologies. This view concept turned out
to be of additional value, as it also provides a mechanism to impose
different semantics on the same syntactical structure.
- NAO - The NEPOMUK Annotation Ontology is an ontology for annotation,
providing vocabulary which is commonly required to annotate resources
on the semantic desktop. NAO includes graph metadata vocabulary for describing,
or annotating, existing named graphs.
- NIE - The NEPOMUK
Information Element set of ontologies provide vocabulary for
elements which are commonly present on the semantic desktop. The
following documents collectively make up the complete
specifications for the Nepomuk Information Element Ontology
- NIE (core) - NEPOMUK Information Element Core Ontology
- NFO - NEPOMUK File Ontology
- NCO - NEPOMUK Contact Ontology
- NMO - NEPOMUK Message Ontology
- NCAL - NEPOMUK Calendar Ontology
- NEXIF - NEPOMUK EXIF Ontology
- NID3 - NEPOMUK ID3 Ontology
- PIMO - Personal Information Model ontology can be used to express Personal Information Models of individuals.
- TMO - Task Model Ontology can be used to describe personal tasks of individuals, as well known as to-do lists.
Contact & Feedback
The ontology maintainers collaborate using a sourceforge project, to contact
responsible ontology maintainers, read
Maintenance and download
The NEPOMUK ontologies are maintained by the
OSCA-Foundation and contributors from open source projects. This page and
the ontologies are kept in a
subversion repository here. You can download it using subversion clients.
Publications & Presentations
This is a list of publications by NEPOMUK researchers related to the Social Semantic Desktop Ontologies.
- Distributed Knowledge Representation on the Social Semantic
Desktop: Named Graphs, Views and Roles in NRL, by Michael Sintek,
Ludger van Elst, Simon Scerri and Siegfried Handschuh. European
Semantic Web Conference (ESWC07), Innsbruck, Austria. June 2007. [PDF] [Presentation]
- A Protégé Plug-in Development to Support the
NEPOMUK Representational Language, by Milena Caires, Simon Scerri,
Siegfried Handschuh, Michael Sintek, Ludger van Elst. 10th
International Protégé Conference, Budapest, Hungary. July
2007. [PDF] [Presentation]
The following are applications that handle or work with Social Semantic Desktop Ontologies.
The NRL Translator translates plain RDF/S as well as Protege RDF/S
(RDF/S XML serialization) into NRL (TriG or RDF/S XML serialization). Available as:
- Online Service [Link]
- A Downloadable Script
- Protégé NRL Exporter Plugin [Link]
Copyright © 2006-2008 Nepomuk Consortium®
Copyright © 2009 OSCAF and contributors
This work is made available under the terms of Nepomuk software license
and the OSCAF