4,686 research outputs found

    Prosodic transcription of Glasgow English: an evaluation study of GlaToBI

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    GlaToBI, a version of the ToBI prosodic transcription system which can be used to transcribe the intonation patterns of western Scottish (Glasgow) English, is currently under development. An assessment of GlaToBI, similar to the evaluation studies that were undertaken for the original ToBI system [7], and for GToBI, a version developed for German [4], has been carried out to test the new system 's reliability, learnability and comprehensiveness. The results of this study show that this adaptation of the ToBI system can be applied with the expected level of reliability to the transcription of Glasgow English. 1. INTRODUCTION Very little corpus based work has been done on the prosodic features of English dialects other than Standard American and southern British (Received Pronunciation). However, with the creation of databases such as the University of Edinburgh's HCRC Map Task corpus [1], the predominant dialect of which is western Scottish (Glasgow) English, the opportunity has arisen..

    Phenalene-phosphazene complexes: effect of exocyclic charge densities on the cyclotriphosphazene ring system

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    The synthesis and properties of a new series of 1,9-diamino-substituted phenalene complexes of the cyclotriphosphazene ring system is described. One of the compounds is shown to be amphoteric, and this behavior allows an examination of the response of the phosphazene linkage to variations in exocyclic charge density at the spiro center in a plane perpendicular to the cyclotriphosphazene ring system. ^(31)P NMR spectroscopy indicates that substituent lone pairs with this orientation are not effective in long-range delocalization within the phosphazene linkage (in accord with our theoretical model of spiro delocalization). An X-ray crystal structure of one compound (7) identifies the presence of clathrated molecules of chloroform together with doubly hydrogen-bonded pairs of the phenalene-phosphazene complexes in the lattice. Crystal data for 7 (C_(13)H_8Cl_4N_5P_3•CHCl_3): monoclinic space group P2_1/c, a = 12.401 (4) Å, b = 28.404 (6) Å, c = 12.962 (3) Å, β = 91.76 (2)°, V = 4564 (2) Å^3, Z = 8, R = 0.050 for 4525 reflections

    Noncooperatively Optimized Tolerance: Decentralized Strategic Optimization in Complex Systems

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    We introduce noncooperatively optimized tolerance (NOT), a generalization of highly optimized tolerance (HOT) that involves strategic (game theoretic) interactions between parties in a complex system. We illustrate our model in the forest fire (percolation) framework. As the number of players increases, our model retains features of HOT, such as robustness, high yield combined with high density, and self-dissimilar landscapes, but also develops features of self-organized criticality (SOC) when the number of players is large enough. For example, the forest landscape becomes increasingly homogeneous and protection from adverse events (lightning strikes) becomes less closely correlated with the spatial distribution of these events. While HOT is a special case of our model, the resemblance to SOC is only partial; for example, the distribution of cascades, while becoming increasingly heavy-tailed as the number of players increases, also deviates more significantly from a power law in this regime. Surprisingly, the system retains considerable robustness even as it becomes fractured, due in part to emergent cooperation between neighboring players. At the same time, increasing homogeneity promotes resilience against changes in the lightning distribution, giving rise to intermediate regimes where the system is robust to a particular distribution of adverse events, yet not very fragile to changes

    Spectroscopic study of unique line broadening and inversion in low-pressure microwave generated water plasmas

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    It was demonstrated that low pressure (~0.2 Torr) water vapor plasmas generated in a 10 mm inner diameter quartz tube with an Evenson microwave cavity show at least two features which are not explained by conventional plasma models. First, significant (> 0.25 nm) hydrogen Balmer_ line broadening, of constant width, up to 5 cm from the microwave coupler was recorded. Only hydrogen, and not oxygen, showed significant line broadening. This feature, observed previously in hydrogen-containing mixed gas plasmas generated with high voltage dc and rf discharges was explained by some researchers to result from acceleration of hydrogen ions near the cathode. This explanation cannot apply to the line broadening observed in the (electrodeless) microwave plasmas generated in this work, particularly at distances as great as 5 cm from the microwave coupler. Second, inversion of the line intensities of both the Lyman and Balmer series, again, at distances up to 5 cm from the coupler, were observed. The line inversion suggests the existence of a hitherto unknown source of pumping of the optical power in plasmas. Finally, it is notable that other aspects of the plasma including the OH* rotational temperature and low electron concentrations are quite typical of plasmas of this type.Comment: 27 pages, 7 figure

    Scalar Deformations of Schwarzschild Holes and Their Stability

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    We construct two solutions of the minimally coupled Einstein-scalar field equations, representing regular deformations of Schwarzschild black holes by a self-interacting, static, scalar field. One solution features an exponentially decaying scalar field and a triple-well interaction potential; the other one is completely analytic and sprouts Coulomb-like scalar hair. Both evade the no-hair theorem by having partially negative potential, in conflict with the dominant energy condition. The linear perturbation theory around such backgrounds is developed in general, and yields stability criteria in terms of effective potentials for an analog Schr\"odinger problem. We can test for more than half of the perturbation modes, and our solutions prove to be stable against those.Comment: 24 pp, 16 figs, Latex; version published in Int. J. Mod. Phys.

    Theorem-Proving Analysis of Digital Control Logic Interacting with Continuous Dynamics

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    AbstractThis work outlines an equation-based formulation of a digital control program and transducer interacting with a continuous physical process, and an approach using the Coq theorem prover for verifying the performance of the combined hybrid system. Considering thermal dynamics with linear dissipation for simplicity, we focus on a generalizable, physically consistent description of the interaction of the real-valued temperature and the digital program acting as a thermostat. Of interest in this work is the discovery and formal proof of bounds on the temperature, the degree of variation, and other performance characteristics. Our approach explicitly addresses the need to mathematically represent the decision problem inherent in an analog-to-digital converter, which for rare values can take an arbitrarily long time to produce a digital answer (the so-called Buridan's Principle); this constraint ineluctably manifests itself in the verification of thermostat performance. Furthermore, the temporal causality constraints in the thermal physics must be made explicit to obtain a consistent model for analysis. We discuss the significance of these findings toward the verification of digital control for more complex physical variables and fields

    Improving NDT with Automatic Test Case Generation

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    The model-driven development defi nes the software development process as a set of iterations to create models and a set of transformations to obtain new models. From this point of view, this paper presents the enhancement of a model- driven approach, called navigational development techniques (NDT), by means of new models and transformations in order to generate test cases. It also states some conclusions from the research work and practical cases in which this approach was used.Ministerio de Ciencia e Innovación TIN2010-20057-C03-02Ministerio de Ciencia e Innovación TIN 2010-12312-

    Comparative environmental assessment of two materials suited to central tower CSP technology

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    Compatibility of containment materials with molten salt thermal storage media is a significant technical challenge for Concentrating Solar Power plants. Metal alloys in contact with molten salt must have a specific behavior, mechanical properties and resistance to degradation processes that allow them to operate at temperatures above 500 °C, being both respectful to the environment. Firstly, this study presents two types of specific materials to operate at raised temperatures in Concentrating Solar Power plants, particularly the central tower technology. The materials are AISI 347H stainless steel and the Ni-based alloy HRSA INCONEL 617. Then, a Life Cycle Assessment shows the influence and contribution to different impact categories from the elements that compose both metals, demonstrating that materials that provide better mechanical properties could have environmental shortcomings. This paper aims to contribute to an improved understanding of the environmental implications of these materials and which is the best choice in terms of sustainability. The results showed better environmental behavior in the AISI 347H case against INCONEL 617.Publicad
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