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

Jahresbericht der Research Academy Leipzig 2007

Jahresbericht der Research Academy Leipzig 2007:Inhalt - Die Research Academy Leipzig - Rede zum einjährigen Jubiläum der Gründung der Research Academy Leipzig - Die Vorteile von Promotionsschulen Eine Betreuerperspektive - Fächerübergreifende Qualifikationsmaßnahmen: Die Veranstaltungen der Research Academy Leipzig 2007 - Präsentation in der Öffentlichkeit - Kleinkindbetreuung für Kinder der Doktorandinnen und Doktoranden - Das Graduiertenzentrum Mathematik/Informatik und Naturwissenschaften - Graduiertenschule Leipzig School of Natural Sciences – Building with Molecules and Nano-objects BuildMoNa - Deutsch-Französisches Doktorandenkollegium Statistical Physics of Complex Systems - International Max Planck Research School Mathematics in the Sciences - International Research Training Group Diffusion in Porous Materials - Graduiertenkolleg Analysis, Geometrie und ihre Verbindung zu den Naturwissenschaften - Graduiertenkolleg Wissensrepräsentation - Graduiertenkolleg Mechanistische und Anwendungsaspekte nichtkonventioneller Oxidationsreaktionen - Internationales Promotionsprogramm Forschung in Grenzgebieten der Chemie - Das Graduiertenzentrum Lebenswissenschaften - Graduiertenkolleg Interdisziplinäre Ansätze in den Neurowissenschaften InterNeuro - Graduiertenkolleg Funktion von Aufmerksamkeit bei kognitiven Prozessen - Internationales Promotionsprogramm Von der Signalverarbeitung zum Verhalten IPP Signal - International Max Planck Research School The Leipzig School of Human Origins - MD-PhD-Programm der Universität Leipzig - Graduiertenkolleg Universalität und Diversität: Sprachliche Strukturen und Prozesse - Das Graduiertenzentrum Geistes- und Sozialwissenschaften - Internationales Promotionsprogramm Transnationalisierung und Regionalisierung vom 18. Jahrhundert bis zur Gegenwart - Graduiertenkolleg Bruchzonen der Globalisierung - Deutsch als Fremdsprache Transcultural German Studies - Kultureller Austausch Altertumswissenschaftliche, historische und ethnologische Perspektiven - Praktiken gesellschaftlicher Raumproduktionen in Europa Geographische, historische und soziologische Perspektiven - Bildnachweise - Impressu

Explanation and diagnosis services for unsatisfiability and inconsistency in description logics

Description Logics (DLs) are a family of knowledge representation formalisms with formal semantics and well understood computational complexities. In recent years, they have found applications in many domains, including domain modeling, software engineering, configuration, and the Semantic Web. DLs have deeply influenced the design and standardization of the Web Ontology Language OWL. The acceptance of OWL as a web standard has reciprocally resulted in the widespread use of DL ontologies on the web. As more applications emerge with increasing complexity, non-standard reasoning services, such as explanation and diagnosis, have become important capabilities that a DL reasoner should provide. For example, unsatisfiability and inconsistency may arise in an ontology due to unintentional design defects or changes in the ontology evolution process. Without explanations, searching for the cause is like looking for a needle in a haystack. It is, therefore, surprising that most of the existing DL reasoners do not provide explanation services; they provide "Yes/No" answers to satisfiability or consistency queries without giving any reasons. This thesis presents our solution for providing explanation and diagnosis services for DL reasoners. We firstly propose a framework based on resolution to explain inconsistency and unsatisfiability in Description Logic. A sound and complete algorithm is developed to generate explanations for the DL language [Special characters omitted.] ALCHI based on the unsatisfiability and inconsistency patterns in [Special characters omitted.] ALCHI . We also develop a technique based on Shapley values to measure inconsistencies in ontologies for diagnosis purposes. This measure is used to identify which axioms in an input ontology or which parts of these axioms need to be repaired in order to make the input consistent. We also investigate optimization techniques to compute the inconsistency measures based on particular properties of DLs. Based on the above theoretical foundations, a running prototype system is implemented to evaluate the practicability of the proposed services. Our preliminary empirical results show that the resolution based explanation framework and the diagnosis procedure based on inconsistency measures can be applied in the real world application

Polynomial-Time Reasoning Support for Design and Maintenance of Large-Scale Biomedical Ontologies

Description Logics (DLs) belong to a successful family of knowledge representation formalisms with two key assets: formally well-defined semantics which allows to represent knowledge in an unambiguous way and automated reasoning which allows to infer implicit knowledge from the one given explicitly. This thesis investigates various reasoning techniques for tractable DLs in the EL family which have been implemented in the CEL system. It suggests that the use of the lightweight DLs, in which reasoning is tractable, is beneficial for ontology design and maintenance both in terms of expressivity and scalability. The claim is supported by a case study on the renown medical ontology SNOMED CT and extensive empirical evaluation on several large-scale biomedical ontologies

Tools for linguistic variation

Índice / Index / Sommaire:- Introducción a los problemas y métodos según los principios de la Escuela Dialectométrica de Salzburgo (con ejemplos sacados del “Atlante Italo-Svizzero”, AIS) (Hans Goebl).- Some further dialectometrical stops (John Nerbonne, Jelena Prokic, Martijn Wieling and Charlotte Gooskens).- Tools for dialect syntax: the case of CORDIAL-SIN (an annotated corpus of Portuguese dialects) (Ernestina Carrilho).- Le projet Vivaldi: présentation d’un atlas linguistique parlant virtual (Roland Bauer).- Le Thesaurus Occitan: une base de données multimedia consacrée aux dialectes occitans (Guylaine Brun-Trigaud).- The Thesaurus Occitan: a multimedia database dedicated to Occitan dialects; presentation of its morphosyntax module (Pierre-Aurélien Georges).- New methods for the study of grammatical variation and the Audible Corpus of Spoken Rural Spanish (Inés Fernández Ordóñez).- The application of speech synthesis and speech recognition techniques in dialectal studies (María Pilar Perea).- Relevancia del análisis lingüístico en el tratamiento cuantitativo de la variación dialectal (Esteve Clua).- El procesamiento informático de los materiales del Atlas Lingüístico de la Península Ibérica de Tomás Navarro Tomás (Pilar García Mouton).- Un retrato del artículo vasco en el año 1895 mediante el programa VDM (Ekaitz Santazilia).- Technology for prosodic variation (Gotzon Aurrekoetxea and Aitor Iglesias)

News Networks in Early Modern Europe

News Networks in Early Modern Europe attempts to redraw the history of European news communication in the 16th and 17th centuries. News is defined partly by movement and circulation, yet histories of news have been written overwhelmingly within national contexts. This volume of essays explores the notion that early modern European news, in all its manifestations – manuscript, print, and oral – is fundamentally transnational. These 37 essays investigate the language, infrastructure, and circulation of news across Europe. They range from the 15th to the 18th centuries, and from the Ottoman Empire to the Americas, focussing on the mechanisms of transmission, the organisation of networks, the spread of forms and modes of news communication, and the effects of their translation into new locales and languages