209 research outputs found

    Foundational Challenges in Automated Data and Ontology Cleaning in the Semantic Web

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    The application of automated reasoning systems to data cleaning in the Semantic Web raises many challenges on the foundational basis of cleaning agent design. The authors discuss some of them. They finally argue that logic trust in the Semantic Web can only be achieved if it is based on certified reasoning.Junta de Andalucía TIC-13

    Formally Verified Tableau-Based Reasoners for a Description Logic

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    Description Logics are a family of logics used to represent and reason about conceptual and terminological knowledge. One of the most basic description logics is ALC , used as a basis from which to obtain others. Description logics are particularly important to provide a logical basis for the web ontology languages (such as OWL) used in the Semantic Web. In order to increase the reliability of the Semantic Web, formal methods can be applied, and in particular formal verification of its reasoning services can be carried out. In this paper, we present the formal verification of a tableau-based satisfiability algorithm for the logic ALC . The verification has been completed in several stages. First, we develop an abstract formalization of satisfiability-checking of ALC -concepts. Secondly, we define and formally verify a tableau-based algorithm in which the order of rule application and branch selection can be flexibly specified, using a methodology of refinements to transfer the main properties from the ALC abstract formalization. Finally, we obtain verified and executable reasoners from the algorithm via a process of instantiation.Ministerio de Ciencia e Innovación TIN2009-09492Junta de Andalucía TIC-0606

    Psychological, pain, and disability factors influencing the perception of improvement/recovery from physiotherapy in patients with chronic musculoskeletal pain: a cross-sectional study

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    13 p.Objectives: The aim of this study was to identify the possible relationships between psychological, pain, and disability variables with respect to the perception of change/recovery from physiotherapy in patients with chronic musculoskeletal pain (CMP). Methods: A cross-sectional observational study was performed with 150 patients. All patients completed a series of self-administered questionnaires and a series of self-reports to quantify the perception of change with respect to the physiotherapy they underwent, the level of disability and pain intensity, the level of fear of movement, the level of catastrophism, the degree of self-efficacy, the level of therapeutic alliance and their adherence to the physiotherapy. Results: The strongest correlations were between the subjective perception of change and the number of sessions, treatment beliefs, self-efficacy, pain intensity, collaboration, and bonding. The linear regression model showed that the number of sessions, treatment beliefs, self-efficacy, compliance, pain intensity, and bonding were predictors of subjective perception of improvement, with 50% of the variance. Conclusions: Treatment beliefs, therapeutic alliance, degree of self-efficacy, and pain intensity have been shown to be predictors of a subjective perception of improvement in patients with CMP. In turn, multimodal treatments had the greatest positive impact on the subjective perception of improvement

    A Formally Verified Prover for the ALC Description Logic

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    The Ontology Web Language (OWL) is a language used for the Semantic Web. OWL is based on Description Logics (DLs), a family of logical formalisms for representing and reasoning about conceptual and terminological knowledge. Among these, the logic ALC is a ground DL used in many practical cases. Moreover, the Semantic Web appears as a new field for the application of formal methods, that could be used to increase its reliability. A starting point could be the formal verification of satisfiability provers for DLs. In this paper, we present the PVS specification of a prover for ALC , as well as the proofs of its termination, soundness and completeness. We also present the formalization of the well–foundedness of the multiset relation induced by a well–founded relation. This result has been used to prove the termination and the completeness of the ALC prover.Ministerio de Educación y Ciencia TIN2004–0388

    Inner wall filler as a singular and significant source of indoor radon pollution in heritage buildings: An exhalation method-based approach

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    Abstract The presence of radon in buildings is a matter of growing concern in the industry. A further layer of complexity is present in heritage buildings, where sources of exhalation other than those observed in more modern conventional buildings may render diagnosis and intervention even more difficult. This study explored the high exhalation rates originating in the inner fillers in thick elements such as bearing walls and structural floors and vaults characterising historic construction. They were found to be close to the values observed in soils and one to two orders of magnitude greater (range: 32.5 mBq/m2·s to 149.7 mBq/m2·s) than found in the construction materials themselves, such as granite. The radon emitted into building interiors by those members exhibited more or less uniform concentration profiles on all storeys, irrespective of elevation and consequently distance form the soil. Further to the results delivered by an accumulative model, the only explanation for the empirical findings is that the inner filler in structural members sources a substantial fraction of the high exhalation rates. That would open a new exploratory pathway for remedies that should necessarily address all emissions, rather than deeming the soil as the sole or primary source of radon gas. The issue is broached in this article on the grounds of a case study of the Tower of Hercules at Corunna, Spain, a building dating from Roman times and presently used as a museum and monument open to the public

    Evaluation of dihydroquercetin-3-O-glucoside from Malbec grapes as copigment of malvidin-3-O-glucoside

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    [EN] Malbec is a wine grape variety of great phenolic potential characterized for its high levels of anthocyanins and dihydroflavonols. To evaluate the possible implication of dihydroflavonols in the expression of red wine color through reactions of copigmentation or condensation, assays were carried out in wine model systems with different malvidin-3-O-glucoside:dihydroquercetin-3-O-glucoside molar ratios. The addition of increasing levels of dihydroquercetin-3-O-glucoside to a constant malvidin-3-O-glucoside concentration resulted in a hyperchromic effect associated with a darkening of the anthocyanin solutions, greater quantity of color and visual saturation, perceptible to the human eye. Copigmentation and thermodynamic measurements showed that dihydroquercetin-3-O-glucoside can act as an anthocyanin copigment, similar to other usual wine components like flavanols or phenolic acids, although apparently less efficient than flavonols. The high levels of dihydroflavonols existing in Malbec wines in relation to other non-anthocyanin phenolics should make this family of compounds particularly important to explain the color expression in Malbec young red wines

    Economic Effect of Dust Particles on Photovoltaic Plant Production

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    The performance of photovoltaic panels decreases depending on the different factors to which they are subjected daily. One of the phenomena that most affects their energy production is dust deposition. This is particularly acute in desert climates, where the level of solar radiation is extreme. In this work, the effect of dust soiling is examined on the electricity generation of an experimental photovoltaic pilot plant, installed at the Solar Energy Research Center (CIESOL) at the University of Almería. An average reduction of 5% of the power of a photovoltaic plant due to dust contamination has been obtained, this data being used to simulate the economic effect in plants of 9 kWp and 1 and 50 MWp. The economic losses have been calculated, and are capable of being higher than 150,000 €/year in industrial plants of 50 MWp. A cleaning strategy has also been presented, which represents a substantial economic outlay over the years of plant operation

    Search for vector-boson resonances decaying to a top quark and bottom quark in the lepton plus jets final state in pp collisions at √s = 13 TeV with the ATLAS detector

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    A search for new charged massive gauge bosons, W', is performed with the ATLAS detector at the LHC. Data were collected in proton–proton collisions at a center-of-mass energy of √s = 13 TeV and correspond to an integrated luminosity of 36.1 fb−1. This analysis searches for W' bosons in the W' → t ̄ b decay channel in final states with an electron or muon plus jets. The search covers resonance masses between 0.5 and 5.0 TeV and considers right-handed W' bosons. No significant deviation from the Standard Model (SM) expectation is observed and upper limits are set on the W' → t ̄ b cross section times branching ratio and the W' boson effective couplings as a function of the W' boson mass. For right-handed W' bosons with coupling to the SM particles equal to the SM weak coupling constant, masses below 3.15 TeV are excluded at the 95% confidence level. This search is also combined with a previously published ATLAS result for W' → t ̄ b in the fully hadronic final state. Using the combined searches, right-handed W bosons with masses below 3.25 TeV are excluded at the 95% confidence level.Facultad de Ciencias Exacta

    Search for vector-boson resonances decaying to a top quark and bottom quark in the lepton plus jets final state in pp collisions at √s = 13 TeV with the ATLAS detector

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    A search for new charged massive gauge bosons, W', is performed with the ATLAS detector at the LHC. Data were collected in proton–proton collisions at a center-of-mass energy of √s = 13 TeV and correspond to an integrated luminosity of 36.1 fb−1. This analysis searches for W' bosons in the W' → t ̄ b decay channel in final states with an electron or muon plus jets. The search covers resonance masses between 0.5 and 5.0 TeV and considers right-handed W' bosons. No significant deviation from the Standard Model (SM) expectation is observed and upper limits are set on the W' → t ̄ b cross section times branching ratio and the W' boson effective couplings as a function of the W' boson mass. For right-handed W' bosons with coupling to the SM particles equal to the SM weak coupling constant, masses below 3.15 TeV are excluded at the 95% confidence level. This search is also combined with a previously published ATLAS result for W' → t ̄ b in the fully hadronic final state. Using the combined searches, right-handed W bosons with masses below 3.25 TeV are excluded at the 95% confidence level.Facultad de Ciencias Exacta
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