Semantic interoperability is essential on the Semantic Web to enable different information systems to exchange data. Ontology matching has been recognised as a means to achieve semantic interoperability on the Web by identifying similar information in heterogeneous ontologies. Existing ontology matching approaches have two major limitations. The first limitation relates to similarity metrics, which provide a pessimistic value when considering complex objects such as strings and conceptual entities. The second limitation relates to the role of description logic reasoning. In particular, most approaches disregard implicit information about entities as a source of background knowledge. In this thesis, we first present a new similarity function, called the degree of commonality coefficient, to compute the overlap between two sets based on the similarity between their elements. The results of our evaluations show that the degree of commonality performs better than traditional set similarity metrics in the ontology matching task. Secondly, we have developed the Knowledge Organisation System Implicit Mapping (KOSIMap) framework, which differs from existing approaches by using description logic reasoning (i) to extract implicit information as background knowledge for every entity, and (ii) to remove inappropriate correspondences from an alignment. The results of our evaluation show that the use of Description Logic in the ontology matching task can increase coverage. We identify people interested in ontology matching and reasoning techniques as the target audience of this work

Schlagwörter wie „information overload“, „digital natives“ oder „digital immigrants“ prägen die heutige Informations- und Wissensgesellschaft. Zahlreiche wissenschaftliche Untersuchungen belegen zudem nachdrücklich, dass die technische Entwicklung in den nächsten Jahren noch rasanter fortschreitet als man es jemals vermuten durfte. Internet- Kommunikationsangeboten kommt bereits jetzt eine außergewöhnliche Bedeutung zu - mit steigender Tendenz. Außerdem werden Kommunikationsservices wie Web 2.0-Anwendungen als ein zunehmend wichtiger Faktor von Internetnutzung unterstrichen und der aktuelle Trend zur persönlichen Vernetzung über das Internet stets hervorgehoben. Die Bedeutung der Kernnutzungen des Internets als Inhaltsquelle und Kommunikationsform wird demnach auch weiterhin zunehmen. Diesem Trend müssen sich auch Klassifikationssysteme stellen. Die RVK hat mit dem im Oktober 2009 lancierten Web-Portal einen ersten Schritt in Richtung Vernetzung getan. Die bisher auf verschiedenen Internetseiten disparat untergebrachten Informationen zur RVK sowie die Datenbanken zur RVK sind nunmehr unter einer Oberfläche vereint, miteinander verknüpft und mit Elementen sozialer Software (RVK-Wiki zur größeren Transparenz bei Abstimmungsvorgängen) angereichert. Im Kontext des derzeit ebenfalls als beliebtes Schlagwort thematisierten Semantic Web ist das Portal der RVK ein Paradigmenwechsel in der langen Geschichte der RVK: Das gesamte Wissen zur RVK wird entsprechend seiner Bedeutung konzeptionell verbunden und bereits weitgehend maschinenlesbar (beispielsweise bezogen auf die Suchfunktion in der Datenbank RVK-Online) offeriert. Wissensmanagement sowie die Verbesserung der Qualität der umfangreichen Informationen zur RVK auf semantischer Ebene sind sehr verbessert worden, verbunden mit dem RVK-Wiki könnte man gar von einem ersten Impuls in Richtung Web 3.0 für die RVK sprechen. Auch die hierarchische Struktur der RVK trägt wesentlich zum Semantic Web bei, da in einer Klassifikation gerade hierarchische Strukturen zur „Ordnung“ des im Überfluss vorhandenen implizierten Wissens beitragen. Wesentlich ist demnach die Definition der Relationen im Web (und somit der entsprechenden Ontologien und Entitäten), um der Quantität der Angebote im World Wide Web auch entsprechend qualitativ hochwertige Services mit bibliothekarischem Mehrwert entgegenzusetzen. Für das Datenmodell des Semantic Web ist somit die Bereitstellung von nachhaltigen Normdaten wie es für die RVK ja angedacht - respektive fast umgesetzt ist – notwendig.

Thesis (M.C.S.)--Miami University, Dept. of Computer Science and Systems Analysis, 2009. / Title from first page of PDF document. Includes bibliographical references (p. 122-123).

Thèse (M.Inf.) -- Université du Québec à Chicoutimi, programme extensionné de l'Université du Québec à Montréal, 2004. / Bibliogr.: f. [109]-117. Document électronique également accessible en format PDF. CaQCU

Orientador: Claudia Maria Bauzer Medeiros / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-15T00:34:29Z (GMT). No. of bitstreams: 1 Vilar_BrunoSiqueiraCamposMendonca_M.pdf: 1763680 bytes, checksum: 5a3ddb611bfab6ec3f16246598a66a5b (MD5) Previous issue date: 2009 / Resumo: Sistemas de informação de biodiversidade lidam com um conjunto heterogêneo de informações providas por diferentes grupos de pesquisa. A diversificação pode ocorrer com relação 'as espécies estudadas, 'a estruturação das informações coletadas, ao local de estudo, metodologias de trabalho ou objetivos dos pesquisadores, dentre outros fatores. Esta heterogeneidade de dados, usuários e procedimentos dificulta o reuso e o compartilhamento de informações. Este trabalho contribui para diminuir tal obstáculo, melhorando o processo de consulta 'as informações em sistemas de biodiversidade. Para tanto, propõe um mecanismo de expansão de consultas que pré-processa uma consulta de usuário (cientista) agregando informações adicionais, provenientes de ontologias, para aproximar o resultado da intenção do usuário. Este mecanismo é baseado em serviços Web e foi implementado e testado usados dados e casos de uso reais. / Abstract: Biodiversity information systems need and manage heterogeneous information provided by different research groups. Heterogeneity occur with respect to the species studied, the structure of the information gathered, the region of study, the work methodologies, or the vocabularies and objectives of the researchers, among other factors. This heterogeneity of data, users and procedures hampers information sharing and reuse. This work contributes to reduce this obstacle, improving the query processing mechanisms in biodiversity systems. Its main interpretation is a query expansion mechanism that pre-processes a user (scientist) query aggregating additional information from ontologies, thereby approximating query results to what is intended by the user. This mechanism is based on Web services and was implemented and tested using real case studies. / Mestrado / Banco de Dados / Mestre em Ciência da Computação

This dissertation describes a research study conducted to determine the benefits and use of ontology technologies to support a simulation environment that evaluates countermeasures employed to protect military aircraft. Within the military, aircraft represent a significant investment and these valuable assets need to be protected against various threats, such as man-portable air-defence systems. To counter attacks from these threats, countermeasures are deployed, developed and evaluated by utilising modelling and simulation techniques. The system described in this research simulates real world scenarios of aircraft, missiles and countermeasures in order to assist in the evaluation of infra-red countermeasures against missiles in specified scenarios. Traditional ontology has its origin in philosophy, describing what exists and how objects relate to each other. The use of formal ontologies in Computer Science have brought new possibilities for modelling and representation of information and knowledge in several domains. These advantages also apply to military information systems where ontologies support the complex nature of military information. After considering ontologies and their advantages against the requirements for enhancements of the simulation system, an ontology was constructed by following a formal development methodology. Design research, combined with the adaptive methodology of development, was conducted in a unique way, therefore contributing to establish design research as a formal research methodology. The ontology was constructed to capture the knowledge of the simulation system environment and the use of it supports the functions of the simulation system in the domain. The research study contributes to better communication among people involved in the simulation studies, accomplished by a shared vocabulary and a knowledge base for the domain. These contributions affirmed that ontologies can be successfully use to support military simulation systems / Computing / M. Tech. (Information Technology)

M. Tech. (Information Technology, Department of Information and Communications Technology, Faculty of Applied an Computer Sciences), Vaal University of Technolog / One of the main research topics in Semantic Web is the semantic extraction of knowledge stored in relational databases through ontologies. This is because ontologies are core components of the Semantic Web. Therefore, several tools, algorithms and frameworks are being developed to enable the automatic conversion of relational databases into ontologies. Ontologies produced with these tools, algorithms and frameworks needs to be valid and competent for them to be useful in Semantic Web applications within the target knowledge domains. However, the main challenges are that many existing automatic ontology construction tools, algorithms, and frameworks fail to address the issue of ontology verification and ontology competency evaluation. This study investigates possible solutions to these challenges. The study began with a literature review in the semantic web field. The review let to the conceptualisation of a framework for semantic knowledge extraction to deal with the abovementioned challenges. The proposed framework had to be evaluated in a real life knowledge domain. Therefore, a knowledge domain was chosen as a case study. The data was collected and the business rules of the domain analysed to develop a relational data model. The data model was further implemented into a test relational database using Oracle RDBMS. Thereafter, Protégé plugins were applied to automatically construct ontologies from the relational database. The resulting ontologies are further validated to match their structures against existing conceptual database-to-ontology mapping principles. The matching results show the performance and accuracy of Protégé plugins in automatically converting relational databases into ontologies. Finally, the study evaluated the resulting ontologies against the requirements of the knowledge domain. The requirements of the domain are modelled with competency questions (CQs) and mapped to the ontology using SPARQL queries design, execution and analysis against users’ views of CQs answers. Experiments show that, although users have different views of the answers to CQs, the execution of the SPARQL translations of CQs against the ontology does produce outputs instances that satisfy users’ expectations. This indicates that Protégé plugins generated ontology from relational database embodies domain and semantic features to be useful in Semantic Web applications.

Thesis (M.C.S.)--Miami University, Dept. of Computer Science and Systems Analysis, 2007. / Title from first page of PDF document. Includes bibliographical references (p. 86-88).

Thesis (M.S.)--Mississippi State University. Department of Computer Science and Engineering. / Title from title screen. Includes bibliographical references.

Orientador: Cláudia Maria Bauzer Medeiros / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-18T07:07:49Z (GMT). No. of bitstreams: 1 Fedel_GabrieldeSouza_M.pdf: 14390093 bytes, checksum: 63058da33a22121e927f1cdbaff297d3 (MD5) Previous issue date: 2011 / Resumo: A pesquisa em computação aplicada à biodiversidade apresenta muitos desafios, que vão desde o grande volume de dados altamente heterogêneos até a variedade de tipos de usuários. Isto gera a necessidade de ferramentas versáteis de recuperação. As ferramentas disponíveis ainda são limitadas e normalmente só consideram dados textuais, deixando de explorar a potencialidade da busca por dados de outra natureza, como imagens ou sons. Esta dissertação analisa os problemas de realizar consultas multimodais a partir de predicados que envolvem texto e imagem para o domínio de biodiversidade, especificando e implementando um conjunto de ferramentas para processar tais consultas. As contribuições do trabalho, validado com dados reais, incluem a construção de uma ontologia taxonômica associada a nomes vulgares e a possibilidade de apoiar dois perfis de usuários (especialistas e leigos). Estas características estendem o escopo da consultas atualmente disponíveis em sistemas de biodiversidade. Este trabalho está inserido no projeto Bio-CORE, uma parceria entre pesquisadores de computação e biologia para criar ferramentas computacionais para dar apoio à pesquisa em biodiversidade / Abstract: Research on Computing applied to biodiversity present several challenges, ranging from the massive volumes of highly heterogeneous data to the variety in user profiles. This kind of scenario requires versatile data retrieval and management tools. Available tools are still limited. Most often, they only consider textual data and do not take advantage of the multiple data types available, such as images or sounds. This dissertation discusses issues concerning multimodal queries that involve both text and images as search parameters, for the domanin of biodiversity. It presents the specification and implementation of a set of tools to process such queries, which were validate with real data from Unicamp's Zoology Museum. The aim contributions also include the construction of a taxonomic ontology that includes species common names, and support to both researchers and non-experts in queries. Such features extend the scop of queries available in biodiversity information systems. This research is associated with the Biocore project, jointly conducted by researchers in computing and biology, to design and develop computational tools to support research in biodiversity / Mestrado / Banco de Dados / Mestre em Ciência da Computação