How fluent is the fluent speech of people who stutter? A new approach to measuring kinematics with ultrasound

AM deposited 2020-06-22We present a new approach to the investigation of dynamic ultrasound tongue imaging (UTI) data, applied here to analyse the subtle aspects of the fluency of people who stutter (PWS). Fluent productions of CV syllables (C = /k/; V = /, i, /) from three PWS and three control speakers (PNS) were analysed for duration and peak velocity relative to articulatory movement towards (onset) and away from (offset) the consonantal closure. The objective was to apply a replicable methodology for kinematic investigation to speech of PWS in order to test Wingate's Fault-Line hypothesis. As was hypothesised, results show comparable onset behaviours for both groups. Regarding offsets, groups differ in peak velocity. Results suggest that PWS do not struggle initiating consonantal closure (onset). In transition from consonantal closure into the vowel, however, groups appear to employ different strategies expressed in increased variation (PNS) versus decreased mean peak velocity (PWS).casl30pub4219pub3-

Multi-step ultraviolet index forecasting using long short-term memory networks

The ultraviolet index is an international standard metric for measuring the strength of the ultraviolet radiation reaching Earth’s surface at a particular time, at a particular place. Major health problems may arise from an overexposure to such radiation, including skin cancer or premature ageing, just to name a few. Hence, the goal of this work is to make use of Deep Learning models to forecast the ultraviolet index at a certain area for future timesteps. With the problem framed as a time series one, candidate models are based on Recurring Neural Networks, a particular class of Artificial Neural Networks that have been shown to produce promising results when handling time series. In particular, candidate models implement Long Short-Term Memory networks, with the models’ input ranging from uni to multi-variate. The used dataset was collected by the authors of this work. On the other hand, the models’ output follows a recursive multi-step approach to forecast several future timesteps. The obtained results strengthen the use of Long Short-Term Memory networks to handle time series problems, with the best candidate model achieving high performance and accuracy for ultraviolet index forecasting.This work has been supported by FCT - Fundação para a Ciência e a Tecnologia within the R&D Units project scope UIDB/00319/2020 and DSAIPA/AI/0099/2019. The work of Bruno Fernandes is also supported by a Portuguese doctoral grant, SFRH/BD/130125/2017, issued by FCT in Portugal

Matched-accent processing: Bulgarian-English bilinguals do not have a processing advantage with Bulgarian-accented English over native English speech

James Scobbie - ORCID: 0000-0003-4509-6782 https://orcid.org/0000-0003-4509-6782Robin Lickley - ORCID: 0000-0003-2583-5461 https://orcid.org/0000-0003-2583-5461The Interlanguage Intelligibility Benefit hypothesis (ISIB) for Talkers suggests that there is a potential benefit when listening to one’s second language when it is produced in the accent of one’s first language (matched-accent processing). This study explores ISIB, considering listener proficiency. According to second language learning theories, the listener’s second language proficiency determines the extent to which they rely on their first language phonetics, hence the magnitude of ISIB may be affected by listener proficiency. The accuracy and reaction times of Bulgarian-English bilinguals living in the UK were recorded in a lexical decision task. The English stimuli were produced by native English speakers and Bulgarian-English bilinguals. Listeners responded more slowly and less accurately to the matched-accent stimuli than the native English stimuli. In addition, they adapted their reaction times faster to new speakers with a native English accent compared to a Bulgarian accent. However, the listeners with the lowest English proficiency had no advantage in reaction times and accuracy for either accent. The results offer mixed support for ISIB for Talkers and are consistent with second language learning theories, according to which listeners rely less on their native language phonology when their proficiency in the second language has increased.This study was funded by the full-time doctoral bursary of Queen Margaret University.https://www.journal-labphon.org/inpressinpres

Articulatory evidence for feedback and competition in speech production.

We report an experimental investigation of slips of the tongue using a Word Order Competition (WOC) paradigm in which context (entirely non-lexical, mixed) and competitor (whether a possible phoneme substitution would result in a word or not) were crossed. Our primary analysis uses electropalatographic (EPG) records to measure articulatory variation, and reveals that the articulation of onset phonemes is affected by two factors. First, onsets with real word competitors are articulated more similarly to the competitor onset than when the competitor would result in a non-word. Second, onsets produced in a non-lexical context vary more from the intended onset than when the context contains real words. We propose an account for these findings that incorporates feedback between phonological and lexical representations in a cascading model of speech production, and argue that measuring articulatory variation can improve our understanding of the cognitive processes involved in speech productio

Water Body Temperature Model for Assessing Climate Change Impacts on Thermal Cooling

We develop and test a physically based semi-Lagrangian water body temperature model to apply climatological data and thermal pollution from river-based power plants to historical river flow data in order to better understand climate change impacts on surface water temperature and thermal power plant withdrawal allowances. The model is built for rapid assessment and use in Integrated Assessment Models. We first test the standalone model on a 190km river reach, the Delaware River, where we have detailed flow and temperature data. An R2 of 0.88 is obtained on hourly data for this initial test. Next, we integrate the standalone temperature model into a series of models—rainfall-runoff model, water demand model, water resource management model, and power plant uptake and release model—for the contiguous USA (CONUS), with about 19,000 segments total. With this system in place, we then validate the standalone water temperature model within the system for 16 river stations throughout the CONUS, where we have measured daily temperature data. The model performs reasonably well with a median R2 of 0.88. A variety of climate and emissions scenarios are then applied to the model to test regions of higher vulnerability to river temperature environmental violations, making use of output from two GCMs and six emissions scenarios focusing on projections out to 2050. We find that the two GCMs project significantly different impacts to water temperature, driven largely by the resulting changes in streamflow from the two models. We also find significantly different impacts on the withdrawal allowed by thermal power plants due to environmental regulations. Potential impacts on generation are between +3% and -4% by 2050 for the unconstrained emissions case and +3.5% to -2% for the stringent GHG mitigation policy (where 1% is equivalent to 32 TWh, or about 3 billion USD/year using 2005 electricity prices). We also find that once-through cooling plants are most vulnerable to climate change impacts, with summer impacts ranging from -0.8% to -6% for the unconstrained emissions case and +2.1% to -3.7% for the stringent GHG emissions case

Bulgarian vowel reduction in unstressed position : an ultrasound and acoustic investigation

Vowel reduction in Contemporary Standard Bulgarian (CSB) has been variously claimed to involve raising, no change or lowering of the high vowels /iəu/. There is a general agreement that the low vowels /ɛaɔ/ are raised when unstressed. This paper directly measures tongue height using Ultrasound Tongue Imaging (UTI) and relates this measure to the acoustic correlate F1 at vowel midpoint. The six vowels of CSB were paired with respect to frontness (/ɛ, i/, /a, ə/, /ɔ, u/), and the overlap in height of the unstressed lower vowel in each pair was assessed relative to (a) its stressed counterpart and (b) the stressed and (c) unstressed realisations of the lower vowel. There was no evidence of the higher unstressed vowel in each pair being different from its stressed counterpart. The articulatory and acoustic results are not completely aligned, but both diverge from the traditional model of vowel reduction in CSB

Filled pauses in Hungarian: Their phonetic form and function

Filled pauses are natural occurrences in spontaneous speech and they may turn up at any level of the speech planning process and in a number of functions. The aim of this paper is to find out whether the diverse functions of filled pauses correlate with diverse articulations resulting in diverse acoustic structures. Spontaneous narratives are used as research material. The duration of the filled pauses and the frequency values of their first two formants are analyzed. The most frequent form, schwa, shows function-dependent realizations as confirmed by the durational values and by the second formant values of these vowel-like sounds

Persistent acceleration in global sea-level rise since the 1960s

Previous studies reconstructed twentieth-century global mean sea level (GMSL) from sparse tide-gauge records to understand whether the recent high rates obtained from satellite altimetry are part of a longer-term acceleration. However, these analyses used techniques that can only accurately capture either the trend or the variability in GMSL, but not both. Here we present an improved hybrid sea-level reconstruction during 1900–2015 that combines previous techniques at time scales where they perform best. We find a persistent acceleration in GMSL since the 1960s and demonstrate that this is largely (~76%) associated with sea-level changes in the Indo-Pacific and South Atlantic. We show that the initiation of the acceleration in the 1960s is tightly linked to an intensification and a basin-scale equatorward shift of Southern Hemispheric westerlies, leading to increased ocean heat uptake, and hence greater rates of GMSL rise, through changes in the circulation of the Southern Ocean