A Language for Inconsistency-Tolerant Ontology Mapping

Ontology alignment plays a key role in enabling interoperability among various data sources present in the web. The nature of the world is such, that the same concepts differ in meaning, often so slightly, which makes it difficult to relate these concepts. It is the omni-present heterogeneity that is at the core of the web. The research work presented in this dissertation, is driven by the goal of providing a robust ontology alignment language for the semantic web, as we show that description logics based alignment languages are not suitable for aligning ontologies. The adoption of the semantic web technologies has been consistently on the rise over the past decade, and it continues to show promise. The core component of the semantic web is the set of knowledge representation languages -- mainly the W3C (World Wide Web Consortium) standards Web Ontology Language (OWL), Resource Description Framework (RDF), and Rule Interchange Format (RIF). While these languages have been designed in order to be suitable for the openness and extensibility of the web, they lack certain features which we try to address in this dissertation. One such missing component is the lack of non-monotonic features, in the knowledge representation languages, that enable us to perform common sense reasoning. For example, OWL supports the open world assumption (OWA), which means that knowledge about everything is assumed to be possibly incomplete at any point of time. However, experience has shown that there are situations that require us to assume that certain parts of the knowledge base are complete. Employing the Closed World Assumption (CWA) helps us achieve this. Circumscription is a very well-known approach towards CWA, which provides closed world semantics by employing the idea of minimal models with respect to certain predicates which are closed. We provide the formal semantics of the notion of Grounded Circumscription, which is an extension of circumscription with desirable properties like decidability. We also provide a tableaux calculus to reason over knowledge bases under the notion of grounded circumscription. Another form of common sense logic, is default logic. Default logic provides a way to specify rules that, by default, hold in most cases but not necessarily in all cases. The classic example of such a rule is: If something is a bird then it flies. The power of defaults comes from the ability of the logic to handle exceptions to the default rules. For example, a bird will be assumed to fly by default unless it is an exception, i.e. it belongs to a class of birds that do not fly, like penguins. Interestingly, this property of defaults can be utilized to create mappings between concepts of different ontologies (knowledge bases). We provide a new semantics for the integration of defaults in description logics and show that it improves upon previously known results in literature. In this study, we give various examples to show the utility and advantages of using a default logic based ontology alignment language. We provide the semantics and decidability results of a default based mapping language for tractable fragments of description logics (or OWL). Furthermore, we provide a proof of concept system and qualitative analysis of the results obtained from the system when compared to that of traditional mapping repair techniques

Rule-Based Intelligence on the Semantic Web: Implications for Military Capabilities

Rules are a key element of the Semantic Web vision, promising to provide a foundation for reasoning capabilities that underpin the intelligent manipulation and exploitation of information content. Although ontologies provide the basis for some forms of reasoning, it is unlikely that ontologies, by themselves, will support the range of knowledge-based services that are likely to be required on the Semantic Web. As such, it is important to consider the contribution that rule-based systems can make to the realization of advanced machine intelligence on the Semantic Web. This report aims to review the current state-of-the-art with respect to semantic rule-based technologies. It provides an overview of the rules, rule languages and rule engines that are currently available to support ontology-based reasoning, and it discusses some of the limitations of these technologies in terms of their inability to cope with uncertain or imprecise data and their poor performance in some reasoning contexts. This report also describes the contribution of reasoning systems to military capabilities, and suggests that current technological shortcomings pose a significant barrier to the widespread adoption of reasoning systems within the defence community. Some solutions to these shortcomings are presented and a timescale for technology adoption within the military domain is proposed. It is suggested that application areas such as semantic integration, semantic interoperability, data fusion and situation awareness provide the best opportunities for technology adoption within the 2015 timeframe. Other capabilities, such as decision support and the emulation of human-style reasoning capabilities are seen to depend on the resolution of significant challenges that may hinder attempts at technology adoption and exploitation within the 2020 timeframe

Reasoning with Contexts in Description Logics

Harmelen, F.A.H. van [Promotor]Schlobach, K.S. [Copromotor

GQ-BPAOntoSOA: A goal- and object- based semantic framework for deriving software services from an organisation’s goals and riva business process architecture

Understanding a business organisation is a primary activity that is required for deriving service-oriented systems that assist in carrying out the business activities of an organisation. Business IT alignment is one of the hot topics that concerns with aligning business needs and system needs in order to keep a business organisation competitive in a market. One example in this area is the BPAOntoSOA framework that aligned business process architecture and the service-oriented model of computing. The BPAOntoSOA framework is a semantically enriched framework for deriving service oriented architecture candidate software services from a Riva-based business process architecture. The BPAOntoSOA framework was recently proposed in order to align the candidate software services to the business processes presented in a Riva business process architecture. The activities of the BPAOntoSOA framework are structured into two-semantic-based layers that are formed in a top-down manner. The top layer, the BPAOnt ontology instantiation layer, concerned with conceptualising the Riva business process architecture and the associated business process models. The bottom layer, which is the software service identification layer, concerned with the semantic identification of the service-oriented architecture candidate software services and their associated capabilities. In this layer, RPA clusters were used to describe the derived candidate software service. Ontologies were used in order to support addressing the semantic representation. However, the BPAOntoSOA framework has two limitations. First, the derived candidate software services are identified without considering the business goals. Second, the desired quality of service requirements that constrain the functionality of the software services are absent. This research is concerned with resolving these two limitations within the BPAOntoSOA framework. In this research, the original BPAOntoSOA framework has been extended into the GQ-BPAOntoSOA framework. A new semantic-based layer has been added into the two original layers. The new layer is concerned with conceptualising the goal- and quality- oriented models in order to address their absence in the original BPAOntoSOA framework. The new layer is called the GQOnt ontology instantiation layer. This extension has highlighted the need for aligning the models within the original BPAOnt intonation layer with the ones in the new layer. This is because the BPAOnt was the base for the identification of the candidate software services and capabilities. Therefore, a novel alignment approach has been proposed in order to address this need. Also, the original service identification approach is refined in order to adapt with the integration of goals and quality requirements.The GQ-BPAOntoSOA framework, which is a goal-based and quality-linked extended BPAOntoSOA framework, has been evaluated using the Cancer Care Registration process. This is the same case study used in the evaluation of the BPAOntoSOA framework. And this is required in order to investigate the implication of integrating goals and quality requirements into the pre-existing BPAOntoSOA framework-driven candidate software services. This has shown that: (1) the GQOnt ontology does not only contribute to the extension of the BPAOntoSOA framework, yet it also contributes to providing a semantic representation of a business strategy view for an organisation. The GQOnt ontology acts as an independent repository of knowledge in order to have an early agreement between stakeholders with regard to business goals and quality requirements. The semantic representation could be reused for different purposes with respect to the needs. (2) the alignment approach has bridged the gap between goal-oriented models and Riva-based business process architectures. (3) the Riva business process architecture modelling method and business process models have been enriched with the integration of goals and quality requirements in order to provide a rich representation of business process architecture and process models that reflect an important information for the given organisation. (4) The service identification approach used in the original BPAOntoSOA framework has been enriched with goals and quality requirements. This has affected the identification of candidate software services (clusters) and their capabilities. Also, the derived candidate software services have conformed to service-oriented architecture principles. Accordingly, This research has bridged the gap between the BPAOntoSOA framework and the business goals and quality requirements. This is anticipated to lead to highly consistent, correct and complete software service specifications

Effecting strategic change:The work of strategic champions in shaping narrative infrastructure

Organisations are under pressure to expand the boundaries of strategic management to better account for socio-ecological dependencies, and to shape the principles that guide decision-making accordingly. Prior research on strategic change focusses on the role of leadership to sensegive, and the response of organisational members. Within a strategy-asnarrative perspective, narrative infrastructure has been identified as a valuable but underexplored theory to explain how narrative guides the decisions and actions of organisational members and how leaders use narrative infrastructure to sensegive strategic change to the organisation. Yet, we know less on how narrative infrastructure is shifted, and the work of others than leaders to do this. I undertake a grounded study of how strategic champions (individuals working to influence strategic issues) support leadership in initiating and adopting a shift in narrative infrastructure. My analysis reveals that strategic champions undertake six different stages of narrative work: prompting, enrolling, underpinning, reinforcing, reconstituting and revisiting. Across these stages, strategic champions draw on discursive competences to sensegive the new master story to both leaders, and the organisation more broadly. I make two contributions to the research conversation on narrative within strategy-aspractice. First, I extend the metaphor of narrative infrastructure as a set of rails that guide decision-making, and present a more fulsome picture of narrative infrastructure as a rail network - made up of several master stories which may have different, and at times competing, organisational or institutional logics underpinning them. Second, I identify the work of strategic champions to support leadership in prompting, initiating and revisiting a shift in the narrative infrastructure of an organisation, and demonstrate how they build master story legitimacy, understanding and ownership. My thesis also lends insights to practice, identifying the tactics employed and competences to be developed by strategic champions undertaking to expand the boundaries of strategic management and shift the principles that guide decision-making in their organisations

Generic adaptation framework for unifying adaptive web-based systems

The Generic Adaptation Framework (GAF) research project first and foremost creates a common formal framework for describing current and future adaptive hypermedia (AHS) and adaptive webbased systems in general. It provides a commonly agreed upon taxonomy and a reference model that encompasses the most general architectures of the present and future, including conventional AHS, and different types of personalization-enabling systems and applications such as recommender systems (RS) personalized web search, semantic web enabled applications used in personalized information delivery, adaptive e-Learning applications and many more. At the same time GAF is trying to bring together two (seemingly not intersecting) views on the adaptation: a classical pre-authored type, with conventional domain and overlay user models and data-driven adaptation which includes a set of data mining, machine learning and information retrieval tools. To bring these research fields together we conducted a number GAF compliance studies including RS, AHS, and other applications combining adaptation, recommendation and search. We also performed a number of real systems’ case-studies to prove the point and perform a detailed analysis and evaluation of the framework. Secondly it introduces a number of new ideas in the field of AH, such as the Generic Adaptation Process (GAP) which aligns with a layered (data-oriented) architecture and serves as a reference adaptation process. This also helps to understand the compliance features mentioned earlier. Besides that GAF deals with important and novel aspects of adaptation enabling and leveraging technologies such as provenance and versioning. The existence of such a reference basis should stimulate AHS research and enable researchers to demonstrate ideas for new adaptation methods much more quickly than if they had to start from scratch. GAF will thus help bootstrap any adaptive web-based system research, design, analysis and evaluation