How to integrate conservation data in the Linked Open Data Cloud

Ernesto William De Luca (

In conservation the documentation is an integral part of the restorers’ work to describe their restored objects. It is important and indispensable to understand the phases of conservation and to allow decision-making for conservation and conservation procedures. The information they contain about the conducted conservation procedures, as well as the methods and the materials used are an immeasurable store of knowledge for this discipline and build the basis of the knowledge used for the conservation of a given object.

Documentation is very time consuming; conservators have to categorize photos, give detailed description of the procedures and justify decisions about materials. Every conservator delivers his/her own documentation to the respective monument administrations that archive it in their shelves, without any possibility to access them digitally. In this case, the access to already conducted procedures, as well as the provision of the knowledge about the methods and materials used are very difficult, often almost impossible. At the moment, it is not possible to link different documentations that contain information about similar objects, methods or materials used in the same way. These properties are not recognizable, because of this missing link between them.

Ontologies and Cultural Heritage. Ontologies are the central components of semantic tools and have been present in the art and cultural area for some time. For instance, the CIDOC Conceptual Reference Model (CRM) supports the integration, communication and the exchange of differently structured information from the cultural heritage field. Meanwhile, there are some projects that already use these semantic technologies. A project of the British Museum (, allows the collection of all available data as Linked Open Data (LOD). Also, the currently implemented EU project Europeana ( focuses on the global accessibility of cultural information as LOD. According to the EU Commission, a prominent role for the future of the European knowledge and information society is played by sharing the electronic content. In 2009, the German Federal Government had decided to create a German Digital Library (Deutsche Digitale Bibliothek,, which should link numerous German cultural and scientific facilities and integrate them at European level in the Europeana.

The field of conservation is, in this context, still underrepresented. The only semantic contribution in this domain is the Australian project “The Twentieth Century in Paint” (, which investigates paint materials used in art works of the 20th Century in the Asian-Pacific region. One goal of the project is to develop a suitable ontology. This was developed for a specific sub- domain and can be reused, but represents only a very small area of conservation.

To develop a generic conservation ontology, we have to consider the numerous measures and materials, as well as the damage patterns and causes of loss, which can vary greatly depending on the materiality and exposure of the object to be restored. To achieve a high acceptance in the professional world, conservation experts must be involved in this development process. Ontologies in the field of conservation documentation have not yet been developed. This is a big gap in the research infrastructure of conservation and other fields of cultural heritage.

In cooperation with the Cologne Institute of Conservation Sciences (specifically with Prof. Dr. Peter Kozub), we developed a system ( that bases on an own ontology for conservation documentation that includes different semantic relations. The ontology is developed as a basis for semantic processing of documentation for conservators. The TripleStore is based on Erlangen CIDOC Conceptual Reference Model (CRM, and has been extended with VIAF ( and Geonames (

The resulting research is a joint effort of conservators, information and computer scientists in order to help conservators in organizing and retrieving their own documentation semantically. It aims to build on European initiatives and efforts that seek to free access of all cultural heritage information. The prior objective of this work is the preparation of data for the restorers that are automatically linked in the Linked Open Data Cloud. In this way, the access and reuse of scientific data on restoration is made possible not only for conservators, but also for architects, historians, archeologist and interested people.

In the final paper, we will present the system architecture and describe in more details how the ontology has been built. We will give some more concrete examples, in order to make clear how the system uses the information stored in the relational database and in the triple store. The described resources will be made available, as well as the classification of 539 material classes (related mostly to stone conservation).