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...

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.

INTRODUCTION To compose large scale software there has to be agreement about the terms, since our models depend on symbolic linkages among the components. In modestly-sized systems, we implicitely count on such an agreement. Within a specific domain terms are indeed likely to be consistemt, so that specifications can be developed from English (or other natural) language source documents. When combined with a coherent framework we have the underpinnings for a Domain-Specific-Software Architecture (DSSA). In this abstract we propose extending concepts used in object-based structural algebras and DSSA research to a knowledge-based algebra, suitable for composing larger systems that span multiple domains. The principal operations in the algebras are simple and provide for selection from the objects in the source domain space and placing them into new domains that represent the information needed for the composed results. 1. BACKGROUND Divide-and-conquer is an ess

In this paper, we describe an investigation into the reuse and application of an existing ontology for the purpose of specifying and formally developing software for aircraft design. Our goals were to clearly identify the processes involved in the task, and assess the cost-effectiveness of reuse. Our conclusions are that (re)using an ontology is far from an automated process, and instead requires significant effort from the knowledge engineer. We describe and illustrate some intrinsic properties of the ontology translation problem and argue that fully automatic translators are unlikely to be forthcoming in the foreseeable future. Despite the effort involved, our subjective conclusions are that in this case knowledge reuse was cost-effective, and that it would have taken significantly longer to design the knowledge content of this ontology from scratch in our application. Our preliminary results are promising for achieving larger-scale knowledge reuse in the future.

It is essential to reduce the cost of integrating information sources and to provide a path that allows for incremental integration that can be responsive to users' demands. This paper presents an approach to integrating disparate heterogeneous information sources that uses context logic. Our use of context logic reduces the up-front cost of integration, provides an incremental integration path, and allows semantic conflicts within a single information sources or between information sources to be expressed and resolved. Introduction The number of online network-accessible information sources grows daily. The information promises to provide tremendous value for individuals and corporations. The promise will remain unfulfilled, however, until it is possible to integrate and assimilate information from multiple heterogeneous sources. Because it is impossible to predict the users and patterns of usage in our changing information environment, information providers are not willing to pay a ...

The lack of methods for evaluating ontologies in laboratories can be an obstacle to their use in companies. This paper presents a set of emerging ideas in evaluation of ontologies useful for: (1) ontologies developers in the lab, as a foundation from which to perform technical evaluations; (2) end users of ontologies in companies, as a point of departure in the search for the best ontology for their systems; and (3) future research, as a basis upon which to perform progressive and disciplined investigations in this area. After briefly exploring some general questions such as: why, what, when, how and where to evaluate; who evaluates; and, what to evaluate against, we focus on the definition of a set of criteria useful in the evaluation process. Finally, we use some of these criteria in the evaluation of the Bibliographic-Data [5] ontology. 1. Introduction Several years ago, the idea of a knowledge factory emerged when several research groups [3, 7, 9] put their efforts in building ont...

We show how to deliver a sophisticated, yet intuitive, interactive application over the web using off-the-shelf web browsers as the interaction medium. This attracts a large user community, improves the rate of user acceptance, and avoids many of the pitfalls of software distribution. Web delivery imposes a novel set of constraints on user interface design. We outline the tradeoffs in this design space, motivate the choices necessary to deliver an application, and detail the lessons learned in the process. These issues are crucial because the growing popularity of the web guarantees that software delivery over the web will become ever more wide-spread. This application is publicly available at: http://wwwksl -svc.stanford.edu:5915/ Keywords Internet application, remote user interface, active document, CSCW, World Wide Web, Hypertext, HTML, HTTP, Java. 1. Introduction The recent explosion in the popularity of the world-wide web and its associated hypertext markup language (HTML) and...

Ontologies and problem-solving methods are promising candidates for reuse in Knowledge Engineering. Ontologies define domain knowledge at a generic level, while problem-solving methods specify generic reasoning knowledge. Both type of components can be viewed as complementary entities that can be used to configure new knowledge systems from existing, reusable components. In this paper, we give an overview of approaches for ontologies and problem-solving methods. 1 Introduction In 1991, the ARPA Knowledge Sharing Effort [NFF 91] envisioned a new way in which intelligent systems could be built. They proposed the following: "Building knowledgebased systems today usually entails constructing new knowledge bases from scratch. It could be done by assembling reusable components. Systems developers would then only need to worry about creating the specialized knowledge and reasoners new to the specific task of their system. This new system would interoperate with existing systems, us...

We describe an interlingua-based methodology for translating encoded knowledge and present a formalism for declaratively specifying vocabulary translations within a predicate logic interlingua. In this paper we (1) use the formalism to provide a semantics for translation, (2) show that the formalism enables translation to be done as deduction by a standard theorem prover, (3) describe a proof technique for determining whether a given set of rules for translating from one vocabulary to another is sufficient for performing that translation for any theory, and (4) describe techniques for precompiling translation rules that translate directly between two given vocabularies. Motivation Acquiring and representing knowledge is the key to building powerful intelligent systems. Unfortunately, knowledge base construction is difficult and time consuming. The development of most systems requires a new knowledge base to be constructed from scratch. As a result, most systems remain small to medium ...