How to Use Ontobroker- Demonstration-.pdf

- 1 - How to Use Ontobroker - Demonstration - Stefan Decker, Michael Erdmann, Dieter Fensel, Rudi Studer University of Karlsruhe, Institute AIFB, 76128 Karlsruhe, Germany Email: {decker, erdmann, fensel, studer}@aifb.uni-karlsruhe.de, http://www.aifb.uni-karlsruhe.de/WBS/broker Abstract. The World Wide Web (WWW) is currently one of the most important electronic information sources. However, its information retrieval mechanisms and the provided reasoning services are rather limited. Ontobroker consists of a number of languages and tools that enhance query access and inference service in the WWW. The paper provides a detailed description of how to use Ontobroker. 1 Introduction “Intelligence arises at the border between chaos and order” The World Wide Web (WWW) contains huge amounts of knowledge about almost all subjects you can think of. However, the capabilities for automated inferencing are rather limited, so we designed and implemented some tools necessary to enable the use of ontologies for enhancing the web. The broker architecture called Ontobroker [Ontobroker] consists of three core elements: a query interface for formulating queries, an inference engine used to derive answers, and a webcrawler used to collect the required knowledge from the web. This paper provides a manual for using Ontobroker. More details of the whole approach can be found in. [Fensel et al, 1998a][Fensel et al, 1998b]. This paper is organised as follows. In section 2, we demonstrate the client side of Ontobroker and show, how to pose queries with three different approaches: using predefined query schemes, the textual interface and a graphical interface. Section 3 shows the provider side: how to become a knowledge provider, and how to annotate HTMLs. Section 4 ends with some conclusions and future work. 2 Getting Started: the Client Side The Ontobroker query interface is attached to the WWW as a web page. For posing queries one has - 2 - to go to the start page provided by the URL http://w