Research on ontology is becoming increasingly widespread in the computer science community, and its importance is being recognized in a multiplicity of research fields and application areas, including knowledge engineering, database design and integration, information retrieval and extraction. We shall use the generic term information systems, in its broadest sense, to collectively refer to these application perspectives. We argue in this paper that so-called ontologies present their own methodological and architectural peculiarities: on the methodological side, their main peculiarity is the adoption of a highly interdisciplinary approach, while on the architectural side the most interesting aspect is the centrality of the role they can play in an information system, leading to the perspective of ontology-driven information systems.

Ontology mapping is seen as a solution provider in today's landscape of ontology research. As the number of ontologies that are made publicly available and accessible on the Web increases steadily, so does the need for applications to use them. A single ontology is no longer enough to support the tasks envisaged by a distributed environment like the Semantic Web. Multiple ontologies need to be accessed from several applications. Mapping could provide a common layer from which several ontologies could be accessed and hence could exchange information in semantically sound manners. Developing such mappings has been the focus of a variety of works originating from diverse communities over a number of years. In this article we comprehensively review and present these works. We also provide insights on the pragmatics of ontology mapping and elaborate on a theoretical approach for defining ontology mapping.

For 1 ontologies to be cost-effectively deployed, we require a clear understanding of the various ways that ontologies are being used today. To achieve this end, we present a framework for understanding and classifying ontology applications. We identify four main categories of ontology applications: 1) neutral authoring, 2) ontology as specification, 3) common access to information, and 4) ontology-based search. In each category, we identify specific ontology application scenarios. For each, we indicate their intended purpose, the role of the ontology, the supporting technologies, who the principal actors are and what they do. We illuminate the similarities and differences between scenarios. We draw on work from other communities, such as software developers and standards organizations. We use a relatively broad definition of `ontology', to show that much of the work being done by those communities may be viewed as practical applications of ontologies. The common thread is t...

With the grown availability of large and specialized online ontologies, the questions about the combined use of independently developed ontologies have become even more important. Although there is already a lot of research done in this area, there are still many open questions. In this paper we try to classify the problems that may arise into a common framework. We then use that framework to examine several projects that aim at some ontology combination task, thus sketching the state of the art. We conclude with an overview of the different approaches and some recommandations for future research. 1

The word integration has been used with different meanings in the ontology field. This article aims at clarifying the meaning of the word "integration" and presenting some of the relevant work done in integration. We identify three meanings of ontology "integration": when building a new ontology reusing (by assembling, extending, specializing or adapting) other ontologies already available; when building an ontology by merging several ontologies into a single one that unifies all of them; when building an application using one or more ontologies. We discuss the different meanings of "integration", identify the main characteristics of the three different processes and propose three words to distinguish among those meanings: integration, merge and use.

Currently, computers are changing from single, isolated devices into entry points to a worldwide network of information exchange and business transactions called the World Wide Web (WWW). For this reason, support in data, information, and knowledge exchange has become a key issue in current computer technology. The success of the WWW has made it increasingly difficult to find, access, present, and maintain the information required by a wide variety of users. In response to this problem, many new research initiatives and commercial enterprises have been set up to enrich available information with machine processable semantics. This semantic web will provide intelligent access to heterogeneous, distributed information, enabling software products (agents) to mediate between user needs and the information sources available. This paper summarizes ongoing research in the area of the semantic web, focusing especially on ontology technology.

Abstract: The development of new ontologies does not tap the full potential of existing knowledge sources and ongoing ontology engineering methodologies do not address ontology reuse to a satisfactory extent yet. In this paper we analyze the challenges related to the reuse process on the basis of two scenarios in the domains of eRecruitment and medicine, which aim at building domain ontologies by reusing existing knowledge sources.

One of the benefits of formally represented knowledge lies in its potential to be shared. Ontologies have been proposed as the ultimate solution to problems in knowledge sharing. However even when an agreed correspondence between ontologies is reached that is not the end of the problems in knowledge sharing. In this paper we explore a number of realistic knowledge-sharing situations and their related problems for which ontologies fall short in providing a solution. For each situation we propose and analyse alternative solutions.

Abstract. As more and more applications use ontology to represent semantic information, how to support ontology reuse is becoming more and more important. In the OWL Web Ontology Language, the main primitive for ontology reuse is owl:imports. However, this “copy-andpaste” approach suffers a number of problems. In this paper, we propose a new import primitive, called semantic import, to facilitate partial ontology reuse. The main contributions of this paper include the semantics of semantic import and reasoning support for TBox reasoning in simple ontology spaces, where an ontology semantically imports vocabulary from another ontology. The semantic import approach provides a brand new way for partial ontology reuse. 1

Ontology reuse is turning into an important research issue in the ontology field. Ontology reuse can be seen from two points of view: (1) assembling, extending, specializing, adapting other ontologies which are parts of the resulting ontology, or (2) merging different ontologies on the same or similar subject into a single one that unifies all of them. The first kind of reuse is named integration and is the central issue of this paper. In this article, we characterize the integration process, describe and discuss the activities that compose this process and propose an integration methodology. This integration methodology has successfully been applied to build two ontologies in different domains by reusing publicly available ontologies.