Experiencing OptiqueVQS: A Multi-paradigm and Ontology-based Visual Query System for End Users

This is author's post-print version, published version available on http://link.springer.com/article/10.1007%2Fs10209-015-0404-5Data access in an enterprise setting is a determining factor for value creation processes, such as sense-making, decision-making, and intelligence analysis. Particularly, in an enterprise setting, intuitive data access tools that directly engage domain experts with data could substantially increase competitiveness and profitability. In this respect, the use of ontologies as a natural communication medium between end users and computers has emerged as a prominent approach. To this end, this article introduces a novel ontology-based visual query system, named OptiqueVQS, for end users. OptiqueVQS is built on a powerful and scalable data access platform and has a user-centric design supported by a widget-based flexible and extensible architecture allowing multiple coordinated representation and interaction paradigms to be employed. The results of a usability experiment performed with non-expert users suggest that OptiqueVQS provides a decent level of expressivity and high usability and hence is quite promising

Why Jesus and Job spoke bad Welsh : the origin and distribution of V2 orders in Middle Welsh

This thesis covers a wide range of topics from historical to computational and corpus linguistics as well as synchronic and diachronic syntax and information structure. The latest insights in each of these sub-fields of linguistics are necessary to address what has been a vexed problem in the study of Middle Welsh for a long time. Middle Welsh word order is particularly puzzling, because there is a wide range of verb-second patterns and the distribution of those is not at all clear. Secondly, these so-called 'Abnormal Orders' are only found in the Middle Welsh period; Old and Modern Welsh mainly exhibit verb-initial patterns. Verb-second orders are shown to have developed from earlier patterns with hanging topics and focussed cleft constructions by carefully reconstructing their syntactic history in Old Welsh and related Celtic languages. A detailed analysis of a syntactically and pragmatically annotated corpus, built especially for this thesis, reveals that a combination of these features explains which word-order pattern appears in which particular context. From a diachronic syntactic point of view, Middle Welsh shares some crucial developments in the rise of V2 with Early Romance, but it differs in others.Descriptive and Comparative Linguistic

i3MAGE: Incremental, Interactive, Inter-Model Mapping Generation

Data integration is a highly important prerequisite for most enterprise data analyses. While hard in general, a particular concern is about human effort for designing a global integration schema, authoring queries against that schema, and creating mappings to connect data sources with the global schema. Ontology-based data integration (OBDI), which employs ontologies as a target model, reduces the effort for schema design and usage. On the other side, it requires mappings that are particularly difficult to create. Architects who work with OBDI hence need systems to support the process of mapping development. One key type of tooling to support mapping development is automatic or semi-automatic generation of mapping suggestions. While many such tools exist in the wider sphere of data integration, few are built to work in the case of OBDI, where the inter-model gap between relational input schemata and a target ontology has to be bridged. Among those that support OBDI at all, none so far are fully optimized for this specific case by performing a truly inter-model matching while also leveraging distinct but corresponding aspects of both models. We propose i3MAGE, an approach and a system for automatic and semi-automatic generation of mappings in OBDI. The system is built on generic inter-model matching, and it is optimized in various ways for matching relational source schemata to target ontology schemata. To be truly semi-automatic in every respect, i3MAGE works both incrementally, building mappings pay-as-you-go, and interactively in exchange with a human user. We introduce a specialized benchmark and evaluate i3MAGE against a number of other approaches. In addition, we provide examples, where i3MAGE can be deployed in holistic data integration environments

Reasoning with Contexts in Description Logics

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

Pseudo-contractions as Gentle Repairs

Updating a knowledge base to remove an unwanted consequence is a challenging task. Some of the original sentences must be either deleted or weakened in such a way that the sentence to be removed is no longer entailed by the resulting set. On the other hand, it is desirable that the existing knowledge be preserved as much as possible, minimising the loss of information. Several approaches to this problem can be found in the literature. In particular, when the knowledge is represented by an ontology, two different families of frameworks have been developed in the literature in the past decades with numerous ideas in common but with little interaction between the communities: applications of AGM-like Belief Change and justification-based Ontology Repair. In this paper, we investigate the relationship between pseudo-contraction operations and gentle repairs. Both aim to avoid the complete deletion of sentences when replacing them with weaker versions is enough to prevent the entailment of the unwanted formula. We show the correspondence between concepts on both sides and investigate under which conditions they are equivalent. Furthermore, we propose a unified notation for the two approaches, which might contribute to the integration of the two areas