Abstract not found

. This paper discusses technology to support the use of UML for representing ontologies and domain knowledge in the Semantic Web. Two mappings have been defined and implemented using XSLT to produce Java classes and an RDF schema from an ontology represented as a UML class diagram and encoded using XMI. A Java application can encode domain knowledge as an object diagram realised as a network of instances of the generated classes. Support is provided for marshalling and unmarshalling this object-oriented knowledge to and from an RDF/XML serialisation. The paper also proposes an extension to RDF allowing the identification of property-- resource pairs in a model for which `closed world' reasoning cannot be used due to incomplete knowledge. 1

One of the basic problems in the development of techniques for the semantic web is the integration of ontologies. In this paper we deal with a situation where we have various local ontologies, developed independently from each other, and we are required to build an integrated, global ontology as a mean for extracting information from the local ones. In this context, the problem of how to specify the mapping between the global ontology and the local ontologies is a fundamental one, and its solution is essential for establishing an ontology of integration. Description Logics (DLs) are an ideal candidate to formalize ontologies, due to their ability to express complex relationships between concepts. We argue, however, that, for capturing the mapping between different ontologies, the direct use of a DL, even a very expressive one, is not sufficient, and it is necessary to resort to more flexible mechanisms based on the notion of query. Also, we elaborate on the observation that, in the semantic web, the case of mutually inconsistent local ontologies will be very common, and we present the basic ideas in order to extend the integration framework with suitable nonmonotonic features for dealing with this case.

Currently computers are changing from single isolated devices to entry points into a worldwide network of information exchange and business transactions. Therefore, support in the exchange of data, information, and knowledge is becoming the key issue in computer technology today. Ontologies provide a shared and common understanding of a domain that can be communicated between people and across application systems. Ontologies will play a major role in supporting information exchange processes in various areas. A prerequisite for such a role is the development of a joint standard for specifying and exchanging Ontologies well-integrated with existing web standards. This paper deals with precisely this necessity. We will present OIL which is a proposal for such a standard enabling the semantic web, i.e. information with machine processable semantics. It is based on existing proposals such as OKBC, XOL and RDFS, and enriches them with necessary features for expressing rich ontologies. The paper presents the motivation, underlying rationale, modeling primitives, syntax, semantics, tool environment, and applications of OIL.

Abstract not found

The understanding of Semantic Web documents is built upon ontologies that define concepts and relationships of data. Hence, the correctness of ontologies is vital. Ontology reasoners such as RACER and FaCT have been developed to reason ontologies with a high degree of automation. However, complex ontology-related properties may not be expressible within the current web ontology languages, consequently they may not be checkable by RACER and FaCT. We propose to use the software engineering techniques and tools, i.e., Z/EVES and Alloy Analyzer, to complement the ontology tools for checking Semantic Web documents. In this approach, Z/EVES is first applied to remove trivial syntax and type errors of the ontologies. Next, RACER is used to identify any ontological inconsistencies, whose origins can be traced by Alloy Analyzer. Finally Z/EVES is used again to express complex ontology-related properties and reveal errors beyond the modeling capabilities of the current web ontology languages. We have successfully applied this approach to checking a set of military plan ontologies.

In this paper we discuss the problem of document integration for business-to-business e-commerce. We present the infrastructure of the business documentation from the integration perspective and identify the integration subtasks. For each subtask we discuss the arising problems, and available technologies able to solve them.

Abstract not found

In developmental biology ontologies are used amongst other things to describe the anatomy of different species in meaningful ways. These ontologies developed inde-pendently for different species. An interesting task is now to establish homology links across these different species to use the knowledge of one organism for other ones. In this MSc project I developed and implemented an application that displays two on-tologies simultaneously and enables biologists to make homology links across species. Two different visualisation techniques have been developed and implemented to eval-uate how different perspectives of the ontology can help in exploring ontologies and support the biologist in making homology links. An evaluation has shown the potential of the different visualisations of the applica-tion and the functionality in achieving its supposed purpose. i Acknowledgements First of all I want to thank my supervisor Stuart Aitken and my co-superviser Bonnie

. Currently computers are changing from single isolated devices to entry points into a worldwide network of information exchange and business transactions called the World Wide Web (WWW). Therefore support in the exchange of data, information, and knowledge is becoming the key issue in current computer technology. Ontologies provide a shared and common understanding of a domain that can be communicated between people and application systems. Therefore, they may play a major role in supporting information exchange processes in various areas. However, in order to develop their full power, the representation languages for ontologies must be applicable to existing data exchange standards in the World Wide Web. Therefore, we will compare ontology representation languages with document structure techniques (schemata) on the web. We will do this by giving a detailed comparison of OIL, a proposal for expressing ontologies in the Web, with XML Schema, a proposed standard for describing the stru...