3,190 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..

    Beyond technology and finance: pay-as-you-go sustainable energy access and theories of social change

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    Two-thirds of people in sub-Saharan Africa lack access to electricity, a precursor of poverty reduction and development. The international community has ambitious commitments in this regard, e.g. the UN's Sustainable Energy for All by 2030. But scholarship has not kept up with policy ambitions. This paper operationalises a sociotechnical transitions perspective to analyse for the first time the potential of new, mobileenabled, pay-as-you-go approaches to financing sustainable energy access, focussing on a case study of pay-as-you-go approaches to financing solar home systems in Kenya. The analysis calls into question the adequacy of the dominant, two-dimensional treatment of sustainable energy access in the literature as a purely financial/technology, economics/ engineering problem (which ignores sociocultural and political considerations) and demonstrates the value of a new research agenda that explicitly attends to theories of social change – even when, as in this paper, the focus is purely on finance. The paper demonstrates that sociocultural considerations cut across the literature's traditional two-dimensional analytic categories (technology and finance) and are material to the likely success of any technological or financial intervention. It also demonstrates that the alignment of new payas- you-go finance approaches with existing sociocultural practices of paying for energy can explain their early success and likely longevity relative to traditional finance approaches

    Cross-level Validation of Topological Quantum Circuits

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    Quantum computing promises a new approach to solving difficult computational problems, and the quest of building a quantum computer has started. While the first attempts on construction were succesful, scalability has never been achieved, due to the inherent fragile nature of the quantum bits (qubits). From the multitude of approaches to achieve scalability topological quantum computing (TQC) is the most promising one, by being based on an flexible approach to error-correction and making use of the straightforward measurement-based computing technique. TQC circuits are defined within a large, uniform, 3-dimensional lattice of physical qubits produced by the hardware and the physical volume of this lattice directly relates to the resources required for computation. Circuit optimization may result in non-intuitive mismatches between circuit specification and implementation. In this paper we introduce the first method for cross-level validation of TQC circuits. The specification of the circuit is expressed based on the stabilizer formalism, and the stabilizer table is checked by mapping the topology on the physical qubit level, followed by quantum circuit simulation. Simulation results show that cross-level validation of error-corrected circuits is feasible.Comment: 12 Pages, 5 Figures. Comments Welcome. RC2014, Springer Lecture Notes on Computer Science (LNCS) 8507, pp. 189-200. Springer International Publishing, Switzerland (2014), Y. Shigeru and M.Shin-ichi (Eds.

    Electrophoretic mobility of a charged colloidal particle: A computer simulation study

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    We study the mobility of a charged colloidal particle in a constant homogeneous electric field by means of computer simulations. The simulation method combines a lattice Boltzmann scheme for the fluid with standard Langevin dynamics for the colloidal particle, which is built up from a net of bonded particles forming the surface of the colloid. The coupling between the two subsystems is introduced via friction forces. In addition explicit counterions, also coupled to the fluid, are present. We observe a non-monotonous dependence of the electrophoretic mobility on the bare colloidal charge. At low surface charge density we observe a linear increase of the mobility with bare charge, whereas at higher charges, where more than half of the ions are co-moving with the colloid, the mobility decreases with increasing bare charge.Comment: 15 pages, 8 figure

    Fluctuating lattice Boltzmann

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    The lattice Boltzmann algorithm efficiently simulates the Navier Stokes equation of isothermal fluid flow, but ignores thermal fluctuations of the fluid, important in mesoscopic flows. We show how to adapt the algorithm to include noise, satisfying a fluctuation-dissipation theorem (FDT) directly at lattice level: this gives correct fluctuations for mass and momentum densities, and for stresses, at all wavevectors kk. Unlike previous work, which recovers FDT only as k0k\to 0, our algorithm offers full statistical mechanical consistency in mesoscale simulations of, e.g., fluctuating colloidal hydrodynamics.Comment: 7 pages, 3 figures, to appear in Europhysics Letter

    Transport Phenomena and Structuring in Shear Flow of Suspensions near Solid Walls

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    In this paper we apply the lattice-Boltzmann method and an extension to particle suspensions as introduced by Ladd et al. to study transport phenomena and structuring effects of particles suspended in a fluid near sheared solid walls. We find that a particle free region arises near walls, which has a width depending on the shear rate and the particle concentration. The wall causes the formation of parallel particle layers at low concentrations, where the number of particles per layer decreases with increasing distance to the wall.Comment: 14 pages, 14 figure

    Observations and radiative transfer modelling of a massive dense cold core in G333

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    Cold massive cores are one of the earliest manifestations of high mass star formation. Following the detection of SiO emission from G333.125-0.562, a cold massive core, further investigations of the physics, chemistry and dynamics of this object has been carried out. Mopra and NANTEN2 molecular line profile observations, Australia Telescope Compact Array (ATCA) line and continuum emission maps, and Spitzer 24 and 70 \mum images were obtained. These new data further constrain the properties of this prime example of the very early stages of high mass star formation. A model for the source was constructed and compared directly with the molecular line data using a 3D molecular line transfer code - MOLLIE. The ATCA data reveal that G333.125-0.562 is composed of two sources. One of the sources is responsible for the previously detected molecular outflow and is detected in the Spitzer 24 and 70 \mum band data. Turbulent velocity widths are lower than other more active regions of G333 which reflects the younger evolutionary stage and/or lower mass of this core. The molecular line modelling requires abundances of the CO isotopes that strongly imply heavy depletion due to freeze-out of this species onto dust grains. The principal cloud is cold, moderately turbulent and possesses an outflow which indicates the presence of a central driving source. The secondary source could be an even less evolved object as no apparent associations with continuum emissions at (far-)infrared wavelengths.Comment: 10 pages, accepted to MNRA

    The 40 and 50 GHz propagation experiments at the Rutherford Appleton Laboratory, UK, using the ITALSAT beacons

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    This paper describes the current experimental program and future plans for the reception of transmissions from the 18.7, 39.6, and 49.5 GHz beacons from the ITALSAT satellite by the Radio Communications Research Unit at Rutherford Appleton Laboratory, UK. The Radio Communications Research Unit, which has had considerable experience in developing experimental millimetric equipment for propagation studies, has initiated the development of a single-channel receiver and a triple-channel receiver to measure propagation effects at 49.5 GHz and 39.6 GHz respectively. The initial location of the receivers will be at Chilbolton, Hampshire, UK

    Screened and Unscreened Phases in Sedimenting Suspensions

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    A coarse-grained stochastic hydrodynamical description of velocity and concentration fluctuations in steadily sedimenting suspensions is constructed, and analyzed using self-consistent and renormalization group methods. We find that there exists a dynamical, non-equilibrium phase transition from an "unscreened" phase in which we recover the Caflisch-Luke (R.E. Caflisch and J.H.C. Luke, Phys. Fluids 28, 759 (1985)) divergence of the velocity variance to a "screened" phase where the velocity fluctuations have a finite correlation length growing as ϕ1/3\phi^{-1/3} where ϕ\phi is the particle volume fraction, in agreement with Segr\`e et. al. (Phys. Rev. Lett. 79, 2574 (1997)) and the velocity variance is independent of system size. Detailed predictions are made for the correlation function in both phases and at the transition.Comment: 4 pages, revtex 1 figur
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