19 research outputs found

    Proceedings of the 11th Workshop on Nonmonotonic Reasoning

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    These are the proceedings of the 11th Nonmonotonic Reasoning Workshop. The aim of this series is to bring together active researchers in the broad area of nonmonotonic reasoning, including belief revision, reasoning about actions, planning, logic programming, argumentation, causality, probabilistic and possibilistic approaches to KR, and other related topics. As part of the program of the 11th workshop, we have assessed the status of the field and discussed issues such as: Significant recent achievements in the theory and automation of NMR; Critical short and long term goals for NMR; Emerging new research directions in NMR; Practical applications of NMR; Significance of NMR to knowledge representation and AI in general

    Pattern recognition beyond classification: An abductive framework for time series interpretation

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    Time series interpretation aims to provide an explanation of what is observed in terms of its underlying processes. The present work is based on the assumption that the common classification-based approaches to time series interpretation suffer from a set of inherent weaknesses, whose ultimate cause lies in the monotonic nature of the deductive reasoning paradigm. In this thesis we propose a new approach to this problem, based on the initial hypothesis that abductive reasoning properly accounts for the human ability to identify and characterize the patterns appearing in a time series. The result of this interpretation is a set of conjectures in the form of observations, organized into an abstraction hierarchy and explaining what has been observed. A knowledge-based framework and a set of algorithms for the interpretation task are provided, implementing a hypothesize-and-test cycle guided by an attentional mechanism. As a representative application domain, interpretation of the electrocardiogram allows us to highlight the strengths of the present approach in comparison with traditional classification-based approaches

    Diagnóstico de fallos en sistemas industriales basado en razonamiento borroso y posibilístico

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    Esta tesis aborda el diagnóstico de fallos en sistemas industriales por técnicas de Inteligencia Artificial, tratando en particular el razonamiento borroso y posibilístico. Inicialmente, se presentan los problemas a resolver en el diagnóstico de sistemas y después se plantean estrategias para abordarlos a partir de diferentes técnicas de Inteligencia Artificial, en donde destacamos los métodos relacionales borrosos que serán la base para nuestra aportación principal. También se han estudiado los sistemas expertos basados en lógica borrosa y que usan tablas de decisión, los sistemas expertos que combinan lógica borrosa con probabilidad y los sistemas de diagnóstico basados en redes Bayesianas. Se experimenta con varias técnicas de diagnóstico descritas en el estado del arte, haciendo combinaciones entre ellas. Una vez experimentadas y evaluadas las anteriores técnicas, vistos los inconvenientes que surgían, se decidió implementar una nueva metodología que diera una mejor solución al problema del diagnóstico. Esta metodología es el diagnóstico posibilístico borroso visto como un problema de optimización lineal. La metodología convierte los enunciados lingüísticos, que componen una base de reglas de un sistema experto borroso, en un conjunto de ecuaciones lineales a través de técnicas relacionales. Luego, estas ecuaciones se utilizan con algoritmos de programación lineal. Algunas modificaciones requieren programación cuadrática. Los resultados obtenidos en esta última aportación en una aplicación de análisis de aceites fueron satisfactorios, presentando al usuario una salida de diagnóstico fácil de interpretar, suficientemente exacta y teniendo en cuenta la incertidumbre en reglas y medidas.Ramírez Valenzuela, JC. (2007). Diagnóstico de fallos en sistemas industriales basado en razonamiento borroso y posibilístico [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1922Palanci

    Becoming (Un)Stable: Twenty Years of Financial Stability Governance at the Bank of England

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    This thesis is the first critical social scientific study of a central bank’s financial stability agenda, in this case the Bank of England. The study is broadly situated in a trajectory of research into geographies of money and finance that is concerned with global financial processes, opening up the black box of institutional practices and the interaction between discourse and the economy. More specifically, the thesis contributes a Deleuzian cultural economy and three key concepts as a means for interrogating the financial stability practices of the central bank in question: assemblage, performativity and (in)stability. The methodology of the thesis has involved creating a financial stability archive from some 2000 documents, texts and videos publically available on the Bank of England website. Texts within this archive were read in a consistent and rigorous way, drawing on a grounded theory approach that was ‘somewhere between abduction and deduction’ (Crang 2003: 132). And, finally, the empirical contribution of the thesis is concerned with financial stability techniques and develops across five chapters concerned, respectively, with press conferences, credit derivatives, Value-at Risk, stress testing and confidence

    The 1995 Goddard Conference on Space Applications of Artificial Intelligence and Emerging Information Technologies

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    This publication comprises the papers presented at the 1995 Goddard Conference on Space Applications of Artificial Intelligence and Emerging Information Technologies held at the NASA/Goddard Space Flight Center, Greenbelt, Maryland, on May 9-11, 1995. The purpose of this annual conference is to provide a forum in which current research and development directed at space applications of artificial intelligence can be presented and discussed

    31th International Conference on Information Modelling and Knowledge Bases

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    Information modelling is becoming more and more important topic for researchers, designers, and users of information systems.The amount and complexity of information itself, the number of abstractionlevels of information, and the size of databases and knowledge bases arecontinuously growing. Conceptual modelling is one of the sub-areas ofinformation modelling. The aim of this conference is to bring together experts from different areas of computer science and other disciplines, who have a common interest in understanding and solving problems on information modelling and knowledge bases, as well as applying the results of research to practice. We also aim to recognize and study new areas on modelling and knowledge bases to which more attention should be paid. Therefore philosophy and logic, cognitive science, knowledge management, linguistics and management science are relevant areas, too. In the conference, there will be three categories of presentations, i.e. full papers, short papers and position papers

    Compositional Ecological Modelling via Dynamic Constraint Satisfaction with Order-of-Magnitude Preferences

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    Centre for Intelligent Systems and their ApplicationsCompositional modelling is one of the most important knowledge-based approaches to automating domain model construction. However, its use has been limited to physical systems due to the specific presumptions made by existing techniques. Based on a critical survey of existing compositional modellers, the strengths and limitations of compositional modelling for its application in the ecological domain are identified and addressed. The thesis presents an approach for effectively building and (re-)using repositories of models of ecological systems, although the underlying methods are domainindependent. It works by translating the compositional modelling problem into a dynamic constraint satisfaction problem (DCSP). This enables the user of the compositional modeller to specify requirements to the model selection process and to find an appropriate model by the use of efficient DCSP solution techniques. In addition to hard dynamic constraints over the modelling choices, the ecologist/ user of the automated modeller may also have a set of preferences over these options. Because ecological models are typically gross abstractions of very complex and yet only partially understood systems, information on which modelling approach is better is limited, and opinions differ between ecologists. As existing preference calculi are not designed for reasoning with such information, a calculus of partially ordered preferences, rooted in order-of-magnitude reasoning, is also devised within this dissertation. The combination of the dynamic constraint satisfaction problem derived from compositional modelling with the preferences provided by the user, forms a novel type of constraint satisfaction problem: a dynamic preference constraint satisfaction problem (DPCSP). In this thesis, four algorithms to solve such DPCSPs are presented and experimental results on their performance discussed. The resulting algorithms to translate a compositional modelling problem into a DCSP, the order-of-magnitude preference calculus and one of the DPCSP solution algorithms constitute an automated compositional modeller. Its suitability for ecological model construction is demonstrated by applications to two sample domains: a set of small population dynamics models and a large model on Mediterranean vegetation growth. The corresponding knowledge bases and how they are used as part of compositional ecological modelling are explained in detail

    Pseudo-contractions as Gentle Repairs

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    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

    Proceedings of The Multi-Agent Logics, Languages, and Organisations Federated Workshops (MALLOW 2010)

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    http://ceur-ws.org/Vol-627/allproceedings.pdfInternational audienceMALLOW-2010 is a third edition of a series initiated in 2007 in Durham, and pursued in 2009 in Turin. The objective, as initially stated, is to "provide a venue where: the cost of participation was minimum; participants were able to attend various workshops, so fostering collaboration and cross-fertilization; there was a friendly atmosphere and plenty of time for networking, by maximizing the time participants spent together"
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