Frequently Asked Questions

The WissKI system is a set of modules which extends the Content Management System Drupal Version 6 by a virtual research environment. The dependencies for Drupal 6 are documented at the Drupal website ( Additionally, the WissKI system has as semantic backend a triplestore instead of Drupal’s database. The graphical text editor is a modular extension of the HTML editor TinyMCE.

To put it in a nutshell, the WissKI system has got the following dependencies:

  • Drupal version 6
  • Any XAMPP package with the following features or a manual installation of:
    • PHP 5.2/5.3
    • MySQL 4.1 or higher respectively alternative PostgreSQL 7.1, MariaDB, MSSQL or other supported database systems
    • Apache
  • ARC2 (ARC RDF Classes for PHP) triplestore ( and optional any SPARQL 1.1 compliant triplestore
  • TinyMCE 3

What programming languages, development environments, repositories are used? Of which amount is the code?

The WissKI software is programmed in PHP and JavaScript. As development environment you can use any PHP development environment (e. g. Eclipse As repositories there are GitHub ( respectively Drupal Git in use.

The code of the WissKI software currently amounts to ca. 40000 lines.

The code documentation is based on Doxygen and is continuously updated and extended. As a user documentation there is the website with detailed information about the software infrastructure inclusive Installation Guide. Furthermore, the theory and the used technology around WissKI are described. In the scope of the second project phase an advanced user portal with more tutorials and examples will be established.

In the scope of the current project the virtual research environment will be developed further based on the WissKI software and in cooperation with the partner institutions a competence center will be established. In this regard, the museums using WissKI (Germanisches Nationalmuseum, Zoologisches Forschungsmuseum Alexander Koenig) provided positions to guarantee the utilisability of the software. On this basis, even after the end of project the maintenance and support of the software are ensured. For long-term proposal and support of non-profit properties the association IGSD - Interessengemeinschaft für semantische Datenverarbeitung e.V. ( - was founded. There will be a spin-off to provide further services. Moreover, the WissKI software is Open Source. Therefore the source code can be completely reviewed and also edited by a third party. You can find the complete WissKI development on GitHub (

Users of single and individually adapted WissKI instances are primarily personally responsible for the maintenance of the instances. However, further future support can be managed with contractual agreements.

Adapting the WissKI modules after updating external basic modules is in the interest of all WissKI users and especially of the museums, and therefore prioritized.
For adapting to external third party modules the users are personally responsible. Additional services can be handled by contractual agreements.

During the installation of the WissKI system the ontology to be used is loaded dynamically. The administrator of the WissKI system is able to update the ontology at any time manually.
Maintenance and further development of the ECRM implementation is task of the competence center mentioned above.

The operator is personally responsible for the security of the operating system and installed server software like e. g. Apache, MySQL, Drupal.
Regarding WissKI, it is in the interest of the museums to provide for a running system so that WissKI security measures obtain top priority.

Being in the interest of the museums to provide for a running system security measures obtain top priority. Consequently, security holes will be eliminated promptly.

Currently, the basic system of the WissKI software is Drupal 6 which is still completely supported at the moment (see Nevertheless, we are already working on a prototype for a follow-up system based on Drupal 7 in the scope of the current second project phase.

The WissKI system stores its data selectively in a triplestore based on the Drupal data back end or in any SPARQL 1.1 endpoint. The physical data management is ceded to the user and at this point flexible.

Consumption of resources and time response of the WissKI system primarily depend on the underlying basic system Drupal and the used triplestore. Drupal demonstrates its power as content management system e. g. on the websites of the White House ( and MTV ( In the scope of the project Synat ( the Poznan Supercomputing and Networking Center integrates the data of the polish libraries, archives and museums into a SPARQL end point using the triplestore BigOWLIM which answers live despite this amount of data. Based on Drupal and by means of an appropriate data back end, e. g. BigOWLIM, WissKI is also applicable for great amounts of data.

The WissKI system consists of a set of modules which extends the Content Management System Drupal Version 6 by a virtual research environment. Respectively, the data and data acquisition forms are provided via the browser to the computer of the user. The WissKI system is not influenced by crashes of the user’s computer. In case of a server crash the current mechanisms based on Apache and MySQL provide data consistency.

According to the system configuration of the server the current recovery methods of the data base system respectively server system are used.

The user is responsible for the modelling of the custom-designed ontology. Generally, it is possible to handle additional services by contractual agreements.

The respective custom-designed ontology is a sub-ontology of the Erlangen CRM (ECRM). The custom-designed ontology specializes the concepts and properties of the Erlangen CRM, so that they are of use for the domain of the application.

The CIDOC CRM (ISO 21127) provides for all concepts and properties of the custom-designed ontology to be modelled as sub concepts and sub properties of the CIDOC CRM. Since the CIDOC CRM perceives itself as a top level ontology, there is wide scope left. In line with the custom-designed ontology, the user is able to decide by himself which concepts and properties he wants to model for the domain.
The WissKI software does not necessarily depend on the CIDOC CRM, however, the use of the ISO standard is recommended due to long term availability and security as well as data portability.

The user is responsible for controlling the consistency of the underlying custom-designed ontology. The consistency of the ISO standard is guaranteed by the CIDOC Special Interest Group (CIDOC SIG). For checking the consistency of the ECRM and the custom-designed ontology tools like e. g. Protégé ( can be applied.

Who can modify the ontology (Administration of user rights)? The ISO compliant version of the CIDOC CRM ontology can only be modified by the CIDOC SIG. Modifications of the ECRM are carried out via Open Source on GitHub ( Each user can make modifications of the custom-designed ontology by himself. The custom-designed ontology is reloaded via the administration interface of the WissKI system.

The WissKI software is able to import data via the ODBC interface of any SQL server. Furthermore, data can be loaded via the import interfaces of the triple store e. g. in OWL/RDF, RDF/XML, N-Triples, Turtle, SPARQL + SPOG, Legacy XML, HTML tag soup, RSS 2.0, Google Social Graph API, JSON (see The system is able to import normative data in SKOS format.
As export interfaces WissKI provides natively all export formats of the triple store, e. g. OWL/RDF, RDF/XML, N-Triples, Turtle, SPARQL + SPOG, Legacy XML, HTML tag soup, RSS 2.0, Google Social Graph API, JSON (see Additionally, data can be exported in Excel and via an OAI-PMH module in Dublin Core and LIDO. Normative data are exported in SKOS format.

External templates can be integrated via the custom-designed ontology. As vocabularies you can use any normative data like Name Authority Files or Getty TGN (subject to license) in SKOS format. These are manually synchronized by the user.

Large amounts of data can be imported via the ODBC interface and the triplestore interfaces and exported via the OAI-PMH module and the triplestore interfaces.

Basically, due to semantic modelling of data in the WissKI system it is generally non-essential to make modifications on large amounts of data sets, because each identity only exists once in the system. However, modifications on large amounts of data can be made via the triplestore by means of SPARQL.

The user inputs data via the current Web widgets. In forms the auto-complete function supports data input. The user is self-responsible for checking import data.

The text editor writes the data optionally into the Drupal database as well as into the triplestore.

The WissKI system integrates free text with structured data just like the known Wiki approach. Moreover, the WissKI System supports tagging entities in free text. Data storage of structured data and entities tagged in free text is kept consistent and saved into the triplestore. In this way, saving facts twice is avoided. Gathering structured data as well as tagging entities is supported by loaded normative data and vocabularies.