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.

The AEC industry has long been in need of effective modes of information exchange and knowledge sharing, but their practice in the industry is still far from satisfactory. In order to maintain their competence in a highly competitive environment and a globalized market, many organizations in the AEC industry have aimed at a move towards the development of learning organizations. Knowledge management has been seen as an effective way to have every member of an organization engaged in learning at all levels. At the very centre of knowledge management and learning is knowledge sharing through effective communication. Unfortunately, however, there is a big gap in the AEC industry between existing practice and the ideal in this area. In order to effectively coordinate information and knowledge flow in the AEC industry, this present research has developed a framework for an information system – a Construction Information and Knowledge Protocol/Portal (CIKP) which integrates within it a publish/subscribe system, Semantic Web technology, and Social Web concepts. Publish/subscribe is an appropriate many-to-many, people-to-people communication paradigm for handling a highly fragmented industry such as construction. In order to enrich the expressiveness of publications and subscriptions, Semantic Web technology has been incorporated into this system through the development of ontologies as a formal and interoperable form of knowledge representation. This research first involved the development of a domain-level ontology (AR-Onto) to encapsulate knowledge about actors, roles, and their attributes in the AEC industry. AR-Onto was then extended and tailored to create an application-level ontology (CIKP-Onto) which has been used to support the semantics in the CIKP framework. Social Web concepts have been introduced to enrich the description of publications and subscriptions. Our aim has been to break down linear communication through social involvement and encourage a culture of sharing, and in the end, the CIKP framework has been developed to specify desired services in communicating information and knowledge, applicable technical approaches, and more importantly, the functions required to satisfy the needs of a variety of service scenarios.

Recently much research effort has been devoted to the discovery of relevant Web services. It is widely recognized that adding semantics to service description is the solution to this challenge. Web services with explicit semantic annotation are called Semantic Web Services (SWS). This research proposes an indexation and discovery architecture for SWS, together with a prototype application in the area of bioinformatics. In this approach, a SWS repository is created and maintained by crawling both ontology-oriented UDDI registries and Web sites that hosting SWS. For a given service request, the proposed system invokes the matching algorithm and a candidate set is returned with different degree of matching considered. This approach can add more flexibility to the current industry standards by offering more choices to both the service requesters and publishers. Also, the prototype developed in this research shows the value can be added by using SWS in application areas such as bioinformatics.

The AEC industry has long been in need of effective modes of information exchange and knowledge sharing, but their practice in the industry is still far from satisfactory. In order to maintain their competence in a highly competitive environment and a globalized market, many organizations in the AEC industry have aimed at a move towards the development of learning organizations. Knowledge management has been seen as an effective way to have every member of an organization engaged in learning at all levels. At the very centre of knowledge management and learning is knowledge sharing through effective communication. Unfortunately, however, there is a big gap in the AEC industry between existing practice and the ideal in this area. In order to effectively coordinate information and knowledge flow in the AEC industry, this present research has developed a framework for an information system – a Construction Information and Knowledge Protocol/Portal (CIKP) which integrates within it a publish/subscribe system, Semantic Web technology, and Social Web concepts. Publish/subscribe is an appropriate many-to-many, people-to-people communication paradigm for handling a highly fragmented industry such as construction. In order to enrich the expressiveness of publications and subscriptions, Semantic Web technology has been incorporated into this system through the development of ontologies as a formal and interoperable form of knowledge representation. This research first involved the development of a domain-level ontology (AR-Onto) to encapsulate knowledge about actors, roles, and their attributes in the AEC industry. AR-Onto was then extended and tailored to create an application-level ontology (CIKP-Onto) which has been used to support the semantics in the CIKP framework. Social Web concepts have been introduced to enrich the description of publications and subscriptions. Our aim has been to break down linear communication through social involvement and encourage a culture of sharing, and in the end, the CIKP framework has been developed to specify desired services in communicating information and knowledge, applicable technical approaches, and more importantly, the functions required to satisfy the needs of a variety of service scenarios.

No description available.

Die "Kontextsensitivität" genannte systematische Berücksichtigung von Umweltinformationen durch Anwendungssysteme kann als Querschnittsfunktion im betrieblichen Umfeld in vielen Bereichen einen Nutzen stiften. Wirklich praxistaugliche kontextsensitive Anwendungssysteme, die sich analog zu einem mitdenkenden menschlichen Assistenten harmonisch in die ablaufenden Vorgänge in der Realwelt einbringen, haben einen enormen Bedarf nach umfassenden, d.h. diverse Aspekte der Realwelt beschreibenden Kontextinformationen, die jedoch prinzipbedingt verteilt in verschiedenen Datenquellen, etwa Kontexterfassungssystemen, Endgeräten sowie prinzipiell auch in beliebigen anderen, z.T. bereits existierenden Anwendungen entstehen. Ziel dieser Arbeit ist die Verringerung der Komplexität des Beschaffungsvorganges von verteilten und heterogenen Kontextinformationen durch Bereitstellung einer einfach verwendbaren Methode zur Darstellung eines umfassenden, aus verteilten und heterogenen Datenquellen zusammengetragenen Kontextmodells. Im Besonderen werden durch diese Arbeit zwei Probleme addressiert, zum einen daß ein Konsument von umfassenden Kontextinformationen mehrere Datenquellen sowohl kennen und zugreifen können und zum anderen über die zwischen den einzelnen Kontextinformationen in verschiedenen Datenquellen existierenden, zunächst nicht modellierten semantischen Verbindungen Bescheid wissen muß. Das dazu entwickelte Kontextinformationsintegrations- und -darstellungsverfahren kombiniert daher ein die Beschaffung und Integration von Kontextinformationen aus diversen Datenquellen modellierendes Informationsintegrationsmodell mit einem Kontextdarstellungsmodell, welches die abzubildende Realweltdomäne basierend auf ontologischen Informationen durch in problemspezifischer Weise erweiterte Verfahren des Semantic Web in einer möglichst intuitiven, wiederverwendbaren und modularen Weise modelliert. Nach einer fundierten Anforderungsanalyse des entwickelten Prinzips wird dessen Verwendung und Nutzen basierend auf der Skizzierung der wichtigsten allgemeinen Verwendungsmöglichkeiten von Kontextinformationen im betrieblichen Umfeld anhand eines komplexen betrieblichen Anwendungsszenarios demonstriert. Dieses beinhaltet ein Nutzerprofil, das von diversen Anwendungen, u.a. einem kontextsensitiven KFZ-Navigationssystem, einer Restaurantsuchanwendung sowie einem Touristenführer verwendet wird. Probleme hinsichtlich des Datenschutzes, der Integration in existierende Umgebungen und Abläufe sowie der Skalierbarkeit und Leistungsfähigkeit des Verfahrens werden ebenfalls diskutiert. / Context-awareness, which is the systematic consideration of information from the environment of applications, can provide significant benefits in the area of business and technology. To be really useful, i.e. harmonically support real-world processes as human assistants do it, practical applications need a comprehensive and detailed contextual information base that describes all relevant aspects of the real world. As a matter of principle, comprehensive contextual information arises in many places and data sources, e.g. in context-aware infrastructures as well as in "normal" applications, which may have knowledge about the context based on their functionality to support a certain process in the real world. This thesis facilitates the use of contextual information by reducing the complexity of the procurement process of distributed and heterogenous contextual information. Particularly, it addresses the two problems that a consumer of comprehensive contextual information needs to be aware of and able to access several different data sources and must know how to combine the contextual information taken from different and isolated data sources into a meaningful representation of the context. Especially the latter information cannot be modelled using the current state of the art. These problems are addressed by the development of an integration and representation model for contextual information that allows to compose comprehensive context models using information inside distributed and heterogeneous data sources. This model combines an information integration model for distributed and heterogenous information (which consists of an access model for heterogeneous data sources, an integration model and an information relation model) with a representation model for context that formalizes the representation of the respective real world domain, i.e. of the real world objects and their semantic relations in an intuitive, reusable and modular way based on ontologies. The resulting model consists of five layers that represent different aspects of the information integration solution. The achievement of the objectives is rated based on a requirement analysis of the problem domain. The technical feasibility and usefulness of the model is demonstrated by the implementation of an engine to support the approach as well as a complex application scenario consisting of a user profile that integrates information from several data sources and a couple of context-aware applications, e.g. a context-aware navigation system, a restaurant finder application as well as an enhanced tourist guide that use the user profile. Problems regarding security and social effects, the integration of this solution into existing environments and infrastructures as well as technical issues like the scalability and performance of this model are discussed too.

Kerstin Zimmermann, DERI Innsbruck, stellte herkömmliche Portale vor sowie sog. „Ontologien“. Diese erwachsen aus den elementaren Fragen nach „What“ (topic), „Who“ (person), „When“ (time/event), „Where“ (location) und „How“ (meta). Entscheidend bei den Ontologien: Zur Erstellung ist einiger Aufwand notwendig, der aber sich in Mehrwert auszahlt. Mehr dazu unter http://sw-portal.deri.org/ontologies/swportal.html

Das Original-Dokument wurde in das Format pdf umgewandelt. Kerstin Zimmermann, DERI Innsbruck, stellte herkömmliche Portale vor sowie sog. „Ontologien“. Diese erwachsen aus den elementaren Fragen nach „What“ (topic), „Who“ (person), „When“ (time/event), „Where“ (location) und „How“ (meta). Entscheidend bei den Ontologien: Zur Erstellung ist einiger Aufwand notwendig, der aber sich in Mehrwert auszahlt. Mehr dazu unter http://sw-portal.deri.org/ontologies/swportal.html

Das kulturelle Gedächtnis speichert immer gewaltigere Mengen von Informationen und Daten. Doch nur ein verschwindend geringer Teil der Inhalte ist derzeit über digitale Kanäle recherchierbar und verfügbar. Die Projekte mediaglobe und yovisto ermöglichen, den wachsenden Bestand an audiovisuellen Dokumenten auffindbar und nutzbar zu machen und begleiten Medienarchive in die digitale Zukunft. mediaglobe hat das Ziel, durch automatisierte und semantische Verfahren audiovisuelle Dokumente zur deutschen Zeitgeschichte zu erschließen und verfügbar zu machen. Die Vision von mediaglobe ist ein web-basierter Zugang zu umfassenden digitalen AV-Inhalten in Medienarchiven. Dazu bietet mediaglobe zahlreiche automatisierte Verfahren zur Analyse von audiovisuellen Daten, wie z.B. strukturelle Analyse, Texterkennung im Video, Sprachanalyse oder Genreanalyse. Der Einsatz semantischer Technologien verknüpft die Ergebnisse der AV-Analyse und verbessert qualitativ und quantitativ die Ergebnisse der Multimedia-Suche. Ein Tool zum Rechtemanagement liefert Informationen über die Verfügbarkeit der Inhalte. Innovative und intuitiv bedienbare Benutzeroberflächen machen den Zugang zu kulturellem Erbe aktiv erlebbar. mediaglobe vereinigt die Projektpartner Hasso-Plattner Institut für Softwaresystemtechnik (HPI), Medien-Bildungsgesellschaft Babelsberg, FlowWorks und das Archiv der defa Spektrum. mediaglobe wird im Rahmen des Forschungsprogramms »THESEUS – Neue Technologien für das Internet der Dienste« durch das Bundesministerium für Wirtschaft und Technologie gefördert. Die Videosuchmaschine yovisto hingegen ist spezialisiert auf Aufzeichnungen akademischer Lehrveranstaltungen und implementiert explorative und semantische Suchstrategien. yovisto unterstützt einen mehrstufigen 'explorativen' Suchprozess, in dem der Suchende die Möglichkeit erhält, den Bestand des zugrundeliegenden Medienarchivs über vielfältige Pfade entsprechend seines jeweiligen Interesses zu erkunden, so dass am Ende dieses Suchprozesses Informationen entdeckt werden, von deren Existenz der Suchende bislang nichts wusste. Um dies zu ermöglichen vereinigt yovisto automatisierte semantische Medienanalyse mit benutzergenerierten Metadaten zur inhaltlichen Erschließung von AV-Daten und ermöglicht dadurch eine punktgenaue inhaltsbasierte Suche in Videoarchiven.

Semantic Web Services domain has gained special attention in academia and industry. It has been adopted as a promise to enable automation of all aspects of Web services provision and use, such as service creation, selection, discovery, composition, invocation. For that, the Semantic Web Services community has been devoted to creating tools and techniques that explore the semantic information of these services. However, the state of the art shows that the aplications based on Semantic Services have their own characteristics, interests and priorities. This diversity directly influences the choice of techniques and technologies for handling services, ie, a single tool can have satisfactory results in a particular application and is not appropriate for others. Moreover, these applications can evolve, which implies the need of changing these tools. Aiming to solve this problem, this work proposes an adaptive middleware for managing discovery and invocation of services capable of integrating different tools and techniques according to application needs. In order to validate the work, a case study with Semantic Web Services of education domain is presented, with this, it was noted that the proposed Middleware is efficient for performing the processes of discovery, composition and invocation of services in an adaptable manner. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os Serviços Web Semânticos têm ganhado uma atenção especial pela academia e indústria. Eles têm sido utilizados como uma promessa para possibilitar a automação de todos os aspectos da provisão e uso de Serviços Web, tais como criação, seleção, descoberta, composição e invocação de serviços. Para isso, a comunidade tem se dedicado a criação de ferramentas e técnicas para explorar as informações semânticas destes serviços. Entretanto, como apontado pela comunidade especializada no tema, aplicações baseadas em Serviços Semânticos possuem suas próprias características, interesses e prioridades. Esta diversidade influencia diretamente na escolha das técnicas e tecnologias utilizadas para manipulação de serviços, ou seja, uma mesma ferramenta pode ter resultados satisfatórios em uma determinada aplicação e não ser adequada para outras. Além disso, essas aplicações podem evoluir, o que implica na necessidade de mudança nestas ferramentas. Com o objetivo de contribuir na solução deste problema, propõe-se na pesquisa em pauta um Middleware adaptável para gerenciamento de descoberta e invocação de serviços capaz de integrar diferentes técnicas e ferramentas de acordo com as necessidades da aplicação. Como forma de avaliar o trabalho, realizou-se um estudo de caso envolvendo o uso de Serviços Web Semânticos no domínio de educação, com isso, verificou-se que o Middleware proposto se mostrou eficiente na realização dos processos de descoberta, composição e invocação de serviços de maneira adaptável.