Thomas Riechert

OntoWiki – a tool for social, semantic collaboration

We present OntoWiki, a tool providing support for agile, distributed knowledge engineering scenarios. OntoWiki facilitates the visual presentation of a knowledge base as an information map, with different views on instance data. It enables intuitive authoring of semantic content, with an inline editing mode for editing RDF content, similar to WYSIWYG for text documents. It fosters social collaboration aspects by keeping track of changes, allowing to comment and discuss every single part of a knowledge base, enabling to rate and measure the popularity of content and honoring the activity of users. Ontowiki enhances the browsing and retrieval by offering semantic enhanced search strategies. All these techniques are applied with the ultimate goal of decreasing the entrance barrier for projects and domain experts to collaborate using semantic technologies. In the spirit of the Web 2.0 OntoWiki implements an ”architecture of participation” that allows users to add value to the application as they use it. It is available as open-source software and a demonstration platform can be accessed at http://3ba.se.

OntoWiki - An authoring, publication and visualization interface for the Data Web

OntoWiki is a front-end application for the Semantic Data Web, which was originally developed to support distributed knowledge engineering scenarios. Due to its extensibility it also serves as a development framework for knowledge intensive applications. On the surface, OntoWiki is a generic user interface for arbitrary RDF knowledge graphs. It supports the navigation through RDF knowledge bases using SPARQL-generated lists, tables and trees (e.g. class trees and taxonomies). All resources are automatically represented as hyperlinks and backlinks are created whenever feasible, thus enabling users to easily traverse entire knowledge graphs. Since all collections of resources displayed in OntoWiki are generated by SPARQL queries, they can be further refined by applying additional filters. In order to explore large datasets, a comprehensive statistical data management and visualization method was integrated. We render an architectural overview and explain the navigation, exploration and vi- sualization features provided for RDF based information and derived statistics. To showcase the versatility of OntoWiki and its various deployments in the Linked Data Web, we describe some large-scale use cases in the domains of enterprise data inte- gration, governmental data publication and digital humanities. This article is the first comprehensive presentation of OntoWiki summarizing the advancements after the initial publication in 2006 (4).

Knowledge engineering for historians on the example of the catalogus professorum lipsiensis

Although the Internet, as an ubiquitous medium for communication, publication and research, already significantly influenced the way historians work, the capabilities of the Web as a direct medium for collaboration in historic research are not much explored. We report about the application of an adaptive, semantics-based knowledge engineering approach for the development of a prosopographical knowledge base on the Web - the Catalogus Professorum Lipsiensis. In order to enable historians to collect, structure and publish prosopographical knowledge an ontology was developed and knowledge engineering facilities based on the semantic data wiki On to Wiki were implemented. The resulting knowledge base contains information about more than 14.000 entities and is tightly interlinked with the emerging Web of Data. For access and exploration by other historians a number of access interfaces were developed, such as a visual SPARQL query builder, a relationship finder and a Linked Data interface. The approach is transferable to other prosopographical research projects and historical research in general, thus improving the collaboration in historic research communities and facilitating the reusability of historic research results.

Leveraging semantic data Wikis for distributed requirements elicitation

Using Wikis for the collaborative creation of structured textual content has gained increasing importance in the past decade. As Wikis facilitate the involvement of large user groups to create content in an easy way, their application in large, spatially distributed software development efforts seems to be very promising. In this context, we present a classification of Wiki-based approaches to Requirements Engineering (RE) and discuss their suitability. Next, we introduce the ontology of an approach that aims at supporting the collaboration of stakeholders with regard to the RE process. This approach enables large stakeholder groups to elicit, semantically structure and classify requirements in the very early and creative RE phases. Instead of leveraging text-based Wikis, the approach is based on our semantic data Wiki OntoWiki, which focuses on the structuring and management of fine-grained data by employing Semantic Web technologies. OntoWiki enables the intuitive authoring of Knowledge Bases and facilitates the application of Knowledge Management methods.

Knowledge base shipping to the linked open data cloud

Popular knowledge bases that provide SPARQL endpoints for the web are usually experiencing a high number of requests, which often results in low availability of their interfaces. A common approach to counter the availability issue is to run a local mirror of the knowledge base. Running a SPARQL endpoint is currently a complex task which requires a lot of effort and technical support for domain experts who just want to use the SPARQL interface. With our approach of containerised knowledge base shipping we are introducing a simple to setup methodology for running a local mirror of an RDF knowledge base and SPARQL endpoint with interchangeable exploration components. The flexibility of the presented approach further helps maintaining the publication infrastructure for dataset projects. We are demonstrating and evaluating the presented methodology at the example of the dataset projects DBpedia, Catalogus Professorum Lipsiensium and Sächsisches Pfarrerbuch.