Analysis on Partial Relationship in LOD

Relationships play a key role in Semantic Web to connect the dots between entities (concepts or instances) in a way that enables to absorb the real sense of the entities. Some interesting relationships would give proof for the existence of subject and object in triples which in tern can be defined as evidential relationships. Identifying evidential relationships will yield solutions to some existing inference problems and open doors for new applications and research. Part_of relationships are identified as a special kind of an evidential relationship out of membership, causality and etc. Linked Open data as a global data space would provide a good platform to explore these relationships and solve interesting inference problems. But this is not trivial because LOD does not have a rich schema in terms of the data sets and also the existing work with respect to schema mapping in LOD is limited to concepts and not relationships. This project is based on finding a novel approach to identify partial relationships which is the superset of part_of relationships from LOD instance data by conducting a proper analysis of the data patterns in instance data. Ultimately this approach would provide a way to enhance the shallow schemas in LOD which in tern would be helpful in schema matching in LOD. We apply the determined approach to the DBpedia data set in order to identify the partial relationships in DBpedia

Combining Geospatial and Temporal Ontologies

Publicly available ontologies are growing in number at present. These ontologies describe entities in a domain and the relations among these entities. This thesis describes a method to automatically combine a pair of orthogonal ontologies using cross products. A geospatial ontology and a temporal ontology are combined in this work. Computing the cross product of the geospatial and the temporal ontologies gives a complete set of pairwise combination of terms from the two ontologies. This method offers researchers the benefit of using ontologies that are already existing and available rather than building new ontologies for areas outside their scope of expertise. The resulting framework describes a geospatial domain over all possible temporal granularities or levels, allowing one domain to be understood from the perspective of another domain. Further queries on the framework help a user to make higher order inferences about a domain. In this work, Protege, an open source ontology editor and a knowledge base tool, is used to model ontologies. Protege supports the creation, visualization and manipulation of ontologies in various formats including XML (Extensible Markup Language). Use of standard and extensible languages like XML allows sharing of data across different information systems, and thus supports reuse of these ontologies. Both the geospatial ontology and the temporal ontology are represented in Protege. This thesis demonstrates the usefulness of this integrated spatio-temporal framework for reasoning about geospatial domains. SQL queries can be applied to the cross product to return to the user different kinds of information about their domain. For example, a geospatial term Library can be combined with all terms from the temporal ontology to consider Library over all possible kinds of times, including those that might have been overlooked during previous analyses. Visualizations of cross product spaces using Graphviz provides a means for displaying the geospatial-temporal terms as well as the different relations that link these terms. This visualization step also highlights the structure of the cross product for users. In order to generate a more tractable cross product for analysis purposes, methods for filtering terms from the cross product are also introduced. Filtering results in a more focused understanding of the spatio-temporal framework

An intelligent system for facility management

A software system has been developed that monitors and interprets temporally changing (internal) building environments and generates related knowledge that can assist in facility management (FM) decision making. The use of the multi agent paradigm renders a system that delivers demonstrable rationality and is robust within the dynamic environment that it operates. Agent behaviour directed at working toward goals is rendered intelligent with semantic web technologies. The capture of semantics though formal expression to model the environment, adds a richness that the agents exploit to intelligently determine behaviours to satisfy goals that are flexible and adaptable. The agent goals are to generate knowledge about building space usage as well as environmental conditions by elaborating and combining near real time sensor data and information from conventional building models. Additionally further inferences are facilitated including those about wasted resources such as unnecessary lighting and heating for example. In contrast, current FM tools, lacking automatic synchronisation with the domain and rich semantic modelling, are limited to the simpler querying of manually maintained models.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

An intelligent system for facility management

A software system has been developed that monitors and interprets temporally changing (internal) building environments and generates related knowledge that can assist in facility management (FM) decision making. The use of the multi agent paradigm renders a system that delivers demonstrable rationality and is robust within the dynamic environment that it operates. Agent behaviour directed at working toward goals is rendered intelligent with semantic web technologies. The capture of semantics though formal expression to model the environment, adds a richness that the agents exploit to intelligently determine behaviours to satisfy goals that are flexible and adaptable. The agent goals are to generate knowledge about building space usage as well as environmental conditions by elaborating and combining near real time sensor data and information from conventional building models. Additionally further inferences are facilitated including those about wasted resources such as unnecessary lighting and heating for example. In contrast, current FM tools, lacking automatic synchronisation with the domain and rich semantic modelling, are limited to the simpler querying of manually maintained models

An infrastructure for context-dependent RDF data replication on mobile devices

Der im Rahmen dieser Arbeit vorgestellte Ansatz beschreibt die Erstellung einer technischen Infrastruktur, die selektiv RDF-Daten in Abhängigkeit der Informationsbedürfnisse und den unterschiedlichen Kontexten mobiler Nutzer auf ein mobiles Endgerät repliziert und diese somit in intelligenter Art und Weise unterstützt. Eine Zusammenführung kontextspezifischer Konzepte und semantischer Technologien stellt einen wesentlichen Bestandteil zur Verbesserung der mobilen Informationssuche dar und erhöht gleichzeitig die Präzision mobiler Informationsgewinnungsprozesse. Trotz des vorhandenen Potentials einer proaktiven, kontextabhängigen Replizierung von RDF-Daten, gestaltet sich die Verarbeitung auf mobilen Endgeräten schwierig. Die Gründe dafür liegen in den technischen und netzwerkspezifischen Beschränkungen, in der fehlenden Verarbeitungs- und Verwaltungsfunktionalität von ontologiebasierten Beschreibungsverfahren sowie in der Unzulänglichkeit bestehender Replikationsansätze, sich an verändernde Informationsbedürfnisse sowie an unterschiedliche technische, umgebungsspezifische und infrastrukturbezogene Eigenheiten anzupassen. Verstärkt wird diese Problematik durch das Fehlen ausdrucksstarker Beschreibungsverfahren zur Repräsentation kontextspezifischer Daten. Existierende Ansätze leiden dementsprechend unter der Verwendung proprietärer Datenformate, dem Einsatz serverabhängiger Applikationsinfrastrukturen sowie dem Unvermögen, kontextspezifische Daten auszutauschen. Dies äußert sich in Studien, welche die Berücksichtigung der Informationsbedürfnisse mobiler Nutzer als unzureichend einstuft und einen Großteil der benötigten Informationen als kontextrelevant auszeichnet. Obgleich Fortschritte bei der Adaption von semantischen Technologien und Beschreibungsverfahren zur kontextabhängigen Verarbeitung zu erkennen sind, bleibt eine auf semantische Technologien basierende, proaktive Replizierung von RDF-Daten auf mobile Endgeräte ein offenes Forschungsfeld. Die vorliegende Arbeit diskutiert Möglichkeiten zur Erweiterung der mobilen, kontextspezifischen Datenverarbeitung durch semantische Technologien und beinhaltet eine vergleichende Studie zur Leistungsfähigkeit aktueller mobiler RDF-Frameworks. Kernpunkt ist die formale Beschreibung eines abstrakten Modells zur effizienten Akquise, Repräsentation, Verwaltung und Verarbeitung von Kontextinformationen unter Berücksichtigung der technischen Gegebenheiten mobiler Informationssysteme. Ergänzt wird es durch die formale Spezifikation eines nebenläufigen, transaktionsbasierten Verarbeitungsmodells, welches Vollständigkeits- und Konsistenzbedingungen auf Daten- und Prozessebene berücksichtigt. Der praktische Nutzen des vorliegenden Ansatzes wird anhand typischer Informationsbedürfnisse eines Wissensarbeiters demonstriert. Der Ansatz reduziert Abhängigkeiten zu externen Systemen und ermöglicht Nutzern, unabhängig von zeitlichen, örtlichen und netzwerkspezifischen Gegebenheiten, auf die für sie relevanten Daten zuzugreifen und diese zu verarbeiten. Durch die lokale Verarbeitung kontextbezogener Daten wird sowohl die Privatssphäre des Nutzers gewahrt als auch sicherheitsrelevanten Aspekten Rechnung getragen.This work describes an infrastructure for the selective RDF data replication to mobile devices while considering current and future information needs of mobile users and the different contexts they are operating in. It presents a novel approach in synthesizing context-aware computing concepts with semantic technologies and distributed transaction management concepts for intelligently assisting mobile users while enhancing mobile information seeking behavior and increasing the precision of mobile information retrieval processes. Despite the huge potential of a proactive, context-dependent replication of RDF data, such data can not be efficiently processed on mobile devices due to (i) technical limitations and network-related constraints, (ii) missing processing and management capabilities of ontology-based description frameworks, (iii) the inability of traditional data replication strategies to adapt to changing user information needs and to consider technical, environmental, and infrastructural restrictions of mobile operating systems, and (iv) the dynamic and emergent nature of context, which requires flexible and extensible description frameworks that allow for elaborating on the semantics of contextual constellations as well as on the relationships that exist between them. As a consequence, existing approaches suffer from the deployment of proprietary data formats, server-dependent application infrastructures, and the inability to share and exchange contextual information across system borders. Moreover, results of recently conducted studies reveal that mobile users find their information needs inadequately addressed, where a large share can be attributed as context or context-relevant. Although progress has been made in applying semantic technologies, concepts, and languages to the domain of context-aware computing, a synthesis of those fields for the proactive provision of RDF data replicas on mobile devices remains an open research issue. This work discusses possible fields where context-aware computing can be enhanced using technologies, languages, and concepts from the Semantic Web and contains a comparative study about the performance of current mobile RDF frameworks in replication-specific tasks. The main contribution of this thesis is a formal description of an abstract model that allows for an efficient acquisition, representation, management, and processing of contextual information while taking into account the peculiarities and operating environments of mobile information systems. It is complemented by a formal specification of a concurrently operating transaction-based processing model that considers completeness and consistency requirements on data and process level. We demonstrate the practicability of the presented approach trough a prototypical implementation of context and data providers that satisfy typical information needs of a mobile knowledge worker. As a consequence, dependencies to external systems are reduced and users are equipped with relevant information that adheres to their information needs anywhere and at any time, independent of any network-related constraints. Since context-relevant data are processed directly on a mobile device, security and privacy issues are preserved

Ontology Alignment for Real-World Applications

this paper, we represent the ontologies as trees. The vertices of the trees correspond to concepts in the ontology. Throughout the examples, the left tree represents the global ontology and the right tree represents the local ontolog