PRESENCE: A human-inspired architecture for speech-based human-machine interaction

Recent years have seen steady improvements in the quality and performance of speech-based human-machine interaction driven by a significant convergence in the methods and techniques employed. However, the quantity of training data required to improve state-of-the-art systems seems to be growing exponentially and performance appears to be asymptotic to a level that may be inadequate for many real-world applications. This suggests that there may be a fundamental flaw in the underlying architecture of contemporary systems, as well as a failure to capitalize on the combinatorial properties of human spoken language. This paper addresses these issues and presents a novel architecture for speech-based human-machine interaction inspired by recent findings in the neurobiology of living systems. Called PRESENCE-"PREdictive SENsorimotor Control and Emulation" - this new architecture blurs the distinction between the core components of a traditional spoken language dialogue system and instead focuses on a recursive hierarchical feedback control structure. Cooperative and communicative behavior emerges as a by-product of an architecture that is founded on a model of interaction in which the system has in mind the needs and intentions of a user and a user has in mind the needs and intentions of the system

Beginning Scottish geography teachers' perceptions of education for sustainable development

At the start of the 21st century the global pace of change and challenge continues unabated (Cullingford and Gunn, 2005). Increasingly individuals need to be equipped with the skills to manage and navigate uncertain futures (Irving, 1999). The Scottish Government's [SG] ambitions are high: Our aim is that by 2014 people in Scotland will have developed the knowledge, understanding, skills and values to live more sustainable lives (Scottish Executive [SE], 2006). Cobb, Darling-Hammond and Murangi (1995) cited in Cobb (1999) refer to the pivotal role that education plays in relation to national development. Renewed government support for Education for Sustainable Development [ESD] has been evident in recent curriculum reform - The Executive will ensure that the new Curriculum for Excellence [CfE] integrates education for sustainable development across subject areas (Sustainable Development Education Liaison Group, 22-23rd August 2006). Few would query the importance and relevance of ESD, however, school approaches remain piece-meal and unco-ordinated (Sustainable Development Education Liaison Group [SDLG], 2006)

Computing phonological generalization over real speech exemplars

Though it has attracted growing attention from phonologists and phoneticians Exemplar Theory (e g Bybee 2001) has hitherto lacked an explicit production model that can apply to speech signals An adequate model must be able to generalize but this presents the problem of how to generate an output that generalizes over a collection of unique variable-length signals Rather than resorting to a priori phonological units such as phones we adopt a dynamic programming approach using an optimization criterion that is sensitive to the frequency of similar subsequences within other exemplars the Phonological Exemplar-Based Learning System We show that PEBLS displays pattern-entrenchment behaviour central to Exemplar Theory s account of phonologization (C) 2010 Elsevier Ltd All rights reserve

Effect of Notches on the Axial Fatigue Properties of Structural Steels

The effect of the stress concentration on the zero-to-tension axial fatigue strength of notched members of four structural steels has been studied. For each of the four steels a critical notch severity was found at which a transition in behavior takes place. When the theoretical stress concentration exceeds this critical value the fatigue strength increases instead of continuing to decrease as would normally be expected. The maximum effective stress concentration determined from these tests corresponds to a critical notch severity which is dependent on the material) the geometry of the specimen) and the cyclic conditions of stress. Microscopic examinations of the roots of the notched specimens which did not fail revealed cracking in most cases. Some of the cracks apparently were nonpropagating cracks but the test lives in most cases were insufficient to isolate such cracks positively as non-propagating. A study of other data on non-propagating cracks revealed that the laws governing their formation are not yet fully understood. However, there are indications that the increase in fatigue strength obtained above the critical notch severity is coincident with the formation of non~propagating cracks.The Engineering FoundationAmerican Iron and Steel InstituteChicago Bridge and Iron FoundationThe Welding Research Counci

Wind variability of B supergiants

We present the most suitable data sets available in the International Ultraviolet Explorer (IUE) archive for the study of time-dependent stellar winds in early B supergiants. The UV line profile variability in 11 B0 to B3 stars is analysed, compared and discussed, based on 16 separate data sets comprising over 600 homogeneously reduced high-resolution spectrograms. The targets include ``normal'' stars with moderate rotation rates and examples of rapid rotators. A gallery of grey-scale images (dynamic spectra) is presented, which demonstrates the richness and range of wind variability and highlights different structures in the winds of these stars. This work emphasises the suitability of B supergiants for wind studies, under-pinned by the fact that they exhibit unsaturated wind lines for a wide range of ionization. The wind activity of B supergiants is substantial and has highly varied characteristics. The variability evident in individual stars is classified and described in terms of discrete absorption components, spontaneous absorption, bowed structures, recurrence, and ionization variability and stratification. Similar structures can occur in stars of different fundamental parameters, but also different structures may occur in the same star at a given epoch. We discuss the physical phenomena that may be associated with the spectral signatures. The diversity of wind patterns evident likely reflects the role of stellar rotation and viewing angle in determining the observational characteristics of azimuthally extended structure rooted at the stellar surface. In addition, SEI line-synthesis modelling of the UV wind lines is used to provide further information about the state of the winds in our program stars. Typically the range, implied by the line profile variability, in the product of mass-loss rate and ion fraction (mdot q_i) is a factor of ~ 1.5, when integrated between 0.2 and 0.9 v_infty ; it can however be several times larger over localised velocity regions. At a given effective temperature the mean relative ion ratios can differ by a factor of 5. The general excess in predicted (forward-scattered) emission in the low velocity regime is discussed in terms of structured outflows. Mean ion fractions are estimated over the B0 to B1 spectral classes, and trends in the ionic ratios as a function of wind velocity are described. The low values obtained for the ion fractions of UV resonance lines may reflect the role of clumping in the wind

The origins of postmating reproductive isolation: testing hypotheses in the grasshopper Chorthippus parallelus

Although there are several well-established hypotheses for the origins of postmating isolation during allopatric divergence, there have been very few attempts, to determine their relative importance in nature. We have developed an approach based on knowledge of the differing evolutionary histories of populations within species that allows systematic comparison of the predictions of these hypotheses. In previous work, we have applied this methodology to mating signal variation and premating reproductive isolation between populations of the meadow grasshopper Chorthippus parallelus. Here we review the principles behind our approach and report a study measuring postmating isolation in the same set of populations. The populations have known and differing evolutionary histories and relationships resulting from the colonization of northern Europe following the last glaciation. We use a maximum-likelihood analysis to compare the observed pattern of postmating isolation with the predictions of the hypotheses that isolation primarily evolves either as a result of gradual accumulation of mutations in allopatry, or through processes associated with colonization, such as founder events., We also quantify the extent to which degree of postmating isolation can be predicted by genetic distance. Our results suggest that although there is only a weak correlation between genetic distance and postmating isolation, long periods of allopatry do lead to postmating isolation. In contrast to the pattern of premating isolation described in our previous study, colonization does not seem to be associated with increased postmating isolation

One-loop amplitudes for W+3 jet production in hadron collisions

We employ the recently developed method of generalized $D$-dimensional unitarity to compute one-loop virtual corrections to all scattering amplitudes relevant for the production of a $W$ boson in association with three jets in hadronic collisions, treating all quarks as massless.Comment: 26 pages, 5 figures, v2 to agree with published versio

Semi-Numerical Evaluation of One-Loop Corrections

We present a semi-numerical algorithm to calculate one-loop virtual corrections to scattering amplitudes. The divergences of the loop amplitudes are regulated using dimensional regularization. We treat in detail the case of amplitudes with up to five external legs and massless internal lines, although the method is more generally applicable. Tensor integrals are reduced to generalized scalar integrals, which in turn are reduced to a set of known basis integrals using recursion relations. The reduction algorithm is modified near exceptional configurations to ensure numerical stability. To test the procedure we apply these techniques to one-loop corrections to the Higgs to four quark process for which analytic results have recently become available.Comment: 33 pages, 10 figures, some typos fixed and references added, to appear in Phys. Rev. D. v3 corrects a typo in eq. A2