122 research outputs found

    RELIABILITY OF DIFFERENT METHODS OF DETERMINING INDIVIDUAL INTER-STROKE INTERVALS IN SPRINT KAYAKING

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    The purpose of this study was to explore the reliability of methods for rapidly determining inter-stroke intervals (ISI) of individual kayakers. One participant performed two 150 m trials at a rate of 80 single-strokes/min. ISI were calculated using two criterion measures, visual identification of blade immersion (VID) and peaks in longitudinal acceleration of the kayak hull (ACC). These were compared to ISI from peak footrest force (FRP), initiation of footrest force (FRT), paddle Y axis rotational velocity (PAP) and paddle X axis acceleration (PAA). Least products regression analysis (LPR) revealed that FRP showed the highest reliability, with no fixed or proportional bias compared to VID or ACC. High ISI during the initial strokes influenced the results of the LPR, as such a framework for investigating the reliability of ISI using LPR is suggested where the initial strokes are removed prior to analysis

    Low-cost 3D printed 1  nm resolution smartphone sensor-based spectrometer: instrument design and application in ultraviolet spectroscopy.

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    We report on the development of a low-cost spectrometer, based on off-the-shelf optical components, a 3D printed housing, and a modified Raspberry Pi camera module. With a bandwidth and spectral resolution of ≈60  nm and 1 nm, respectively, this device was designed for ultraviolet (UV) remote sensing of atmospheric sulphur dioxide (SO2), ≈310  nm. To the best of our knowledge, this is the first report of both a UV spectrometer and a nanometer resolution spectrometer based on smartphone sensor technology. The device performance was assessed and validated by measuring column amounts of SO2 within quartz cells with a differential optical absorption spectroscopy processing routine. This system could easily be reconfigured to cover other UV-visible-near-infrared spectral regions, as well as alternate spectral ranges and/or linewidths. Hence, our intention is also to highlight how this framework could be applied to build bespoke, low-cost, spectrometers for a range of scientific applications

    Potential for improved radiation thermometry measurement uncertainty through implementing a primary scale in an industrial laboratory

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    A primary temperature scale requires realising a unit in terms of its definition. For high temperature radiation thermometry in terms of the International Temperature Scale of 1990 this means extrapolating from the signal measured at the freezing temperature of gold, silver or copper using Planck’s radiation law. The difficulty in doing this means that primary scales above 1000 °C require specialist equipment and careful characterisation in order to achieve the extrapolation with sufficient accuracy. As such, maintenance of the scale at high temperatures is usually only practicable for National Metrology Institutes, and calibration laboratories have to rely on a scale calibrated against transfer standards. At lower temperatures it is practicable for an industrial calibration laboratory to have its own primary temperature scale, which reduces the number of steps between the primary scale and end user. Proposed changes to the SI that will introduce internationally accepted high temperature reference standards might make it practicable to have a primary high temperature scale in a calibration laboratory. In this study such a scale was established by calibrating radiation thermometers directly to high temperature reference standards. The possible reduction in uncertainty to an end user as a result of the reduced calibration chain was evaluated

    Thermal Sensation in Older People with and without Dementia Living in Residential Care: New Assessment Approaches to Thermal Comfort Using Infrared Thermography

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    The temperature of the indoor environment is important for health and wellbeing, especially at the extremes of age. The study aim was to understand the relationship between self-reported thermal sensation and extremity skin temperature in care home residents with and without dementia. The Abbreviated Mental Test (AMT) was used to discriminate residents to two categories, those with, and those without, dementia. After residents settled and further explanation of the study given (approximately 15 min), measurements included: tympanic membrane temperature, thermal sensation rating and infrared thermal mapping of non-dominant hand and forearm. Sixty-nine afebrile adults (60–101 years of age) were studied in groups of two to five, in mean ambient temperatures of 21.4–26.6 °C (median 23.6 °C). Significant differences were observed between groups; thermal sensation rating (p = 0.02), tympanic temperature (p = 0.01), fingertip skin temperature (p = 0.01) and temperature gradients; fingertip-wrist p = 0.001 and fingertip-distal forearm, p = 0.001. Residents with dementia were in significantly lower air temperatures (p = 0.001). Although equal numbers of residents per group rated the environment as ‘neutral’ (comfortable), resident ratings for ‘cool/cold’ were more frequent amongst those with dementia compared with no dementia. In parallel, extremity (hand) thermograms revealed visual temperature demarcation, variously across fingertip, wrist, and forearm commensurate with peripheral vasoconstriction. Infrared thermography provided a quantitative and qualitative method to measure and observe hand skin temperature across multiple regions of interest alongside thermal sensation self-report. As an imaging modality, infrared thermography has potential as an additional assessment technology with clinical utility to identify vulnerable residents who may be unable to communicate verbally, or reliably, their satisfaction with indoor environmental conditions

    High-Resolution Hyperspectral Imaging Using Low-Cost Components: Application within Environmental Monitoring Scenarios

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    High-resolution hyperspectral imaging is becoming indispensable, enabling the precise detection of spectral variations across complex, spatially intricate targets. However, despite these significant benefits, currently available high-resolution set-ups are typically prohibitively expensive, significantly limiting their user base and accessibility. These limitations can have wider implications, limiting data collection opportunities, and therefore our knowledge, across a wide range of environments. In this article we introduce a low-cost alternative to the currently available instrumentation. This instrument provides hyperspectral datasets capable of resolving spectral variations in mm-scale targets, that cannot typically be resolved with many existing low-cost hyperspectral imaging alternatives. Instrument metrology is provided, and its efficacy is demonstrated within a mineralogy-based environmental monitoring application highlighting it as a valuable addition to the field of low-cost hyperspectral imaging

    Low-Cost Hyperspectral Imaging with A Smartphone.

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    Recent advances in smartphone technologies have opened the door to the development of accessible, highly portable sensing tools capable of accurate and reliable data collection in a range of environmental settings. In this article, we introduce a low-cost smartphone-based hyperspectral imaging system that can convert a standard smartphone camera into a visible wavelength hyperspectral sensor for ca. £100. To the best of our knowledge, this represents the first smartphone capable of hyperspectral data collection without the need for extensive post processing. The Hyperspectral Smartphone's abilities are tested in a variety of environmental applications and its capabilities directly compared to the laboratory-based analogue from our previous research, as well as the wider existing literature. The Hyperspectral Smartphone is capable of accurate, laboratory- and field-based hyperspectral data collection, demonstrating the significant promise of both this device and smartphone-based hyperspectral imaging as a whole

    A rapidly convecting lava lake at Masaya Volcano, Nicaragua

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    Lava lakes provide a rare opportunity to study conduit flow processes through direct observation of the exposed magma surface. The recent lava lake activity at Masaya volcano (Nicaragua), which commenced in 2015, displayed several unusual phenomena. We report on the dynamics of this rapidly convecting lake, which, to the best of our knowledge manifested the highest lava flow velocities ever reported for a lava lake: 13.7–16.4 m s−1, in addition to unusual fluid dynamic behavior involving alteration in surface flow direction. We studied this system with multiparametric and high time resolution remote sensing measurements, performed during June 2017, including ultraviolet camera observations of SO2 emission rates, near infrared thermal camera measurements and video analyses of the lake surface. Median SO2 emission rates of 3.1 (±0.8) and 3.7 (±0.9) kg s−1 were found, which are lower than previously published estimates, and could represent challenging remote sensing conditions or a waning in lava lake activity. Video analyses enabled characterization of frequent bursts of approximately hemispherical spherical-cap bubbles on the surface with diameters ranging 0.6–8.5 m (median of 2.6 m), and calculation of individual bubble masses, which contribute to active bubble bursting values estimated at 1.9 to 3.9 kg s−1. We show that only a small fraction, 7–17%, of total emission volumes are contributed by these bubbles, based on estimated emission rates of 22.5 and 26.9 kg s−1. Furthermore, periodicity analysis reveals regular 200–300 s oscillations in SO2 emissions. These are not shared by any of our other datasets and particularly during the contemporaenously acquried thermal data, hence, we tentatively assign an atmospheric causal generation mechanism, driven by atmospheric transport and turbulence phenomena, such as eddying. Overall, we highlight the uniquely high velocity and fluid dynamic behavior of Masaya lava lake

    Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

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    A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

    stairs and fire

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