7,176 research outputs found

    Towards a real-time microscopic emissions model

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    This article presents a new approach to microscopic road traffic exhaust emission modelling. The model described uses data from the SCOOT demand-responsive traffic control system implemented in over 170 cities across the world. Estimates of vehicle speed and classification are made using data from inductive detector loops located on every SCOOT link. This data feeds into a microscopic traffic model to enable enhanced modelling of the driving modes of vehicles (acceleration, deceleration, idling and cruising). Estimates of carbon monoxide emissions are made by applying emission factors from an extensive literature review. A critical appraisal of the development and validation of the model is given before the model is applied to a study of the impact of high emitting vehicles. The article concludes with a discussion of the requirements for the future development and benefits of the application of such a model

    Measurement of Intraspinal Pressure After Spinal Cord Injury: Technical Note from the Injured Spinal Cord Pressure Evaluation Study.

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    Intracranial pressure (ICP) is routinely measured in patients with severe traumatic brain injury (TBI). We describe a novel technique that allowed us to monitor intraspinal pressure (ISP) at the injury site in 14 patients who had severe acute traumatic spinal cord injury (TSCI), analogous to monitoring ICP after brain injury. A Codman probe was inserted subdurally to measure the pressure of the injured spinal cord compressed against the surrounding dura. Our key finding is that it is feasible and safe to monitor ISP for up to a week in patients after TSCI, starting within 72 h of the injury. With practice, probe insertion and calibration take less than 10 min. The ISP signal characteristics after TSCI were similar to the ICP signal characteristics recorded after TBI. Importantly, there were no associated complications. Future studies are required to determine whether reducing ISP improves neurological outcome after severe TSCI

    Impact of Driving Cycles on Greenhouse Gas (GHG) Emissions, Global Warming Potential (GWP) and Fuel Economy for SI Car Real World Driving

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    The transport sector is one of the major contributors to greenhouse gas emissions. This study investigated three greenhouse gases emitted from road transport: CO2, N2O and CH4 emissions as a function of engine warm up and driving cycles. Five different urban driving cycles were developed and used including free flow driving and congested driving. An in-vehicle FTIR (Fourier Transform Inferred) emission measurement system was installed on a EURO2 emission compliant SI (Spark Ignition) car for emissions measurement at a rate of 0.5 HZ under real world urban driving conditions. This emission measurement system was calibrated on a standard CVS (Constant Volume Sampling) measurement system and showed excellent agreement on CO2 measurement with CVS results. The N2O and CH4 measurement was calibrated using calibration gas in lab. A MAX710 real time in-vehicle fuel consumption measurement system was installed in the test vehicle and real time fuel consumption was then obtained. The temperatures across the TWC (Three Way Catalyst) and engine out exhaust gas lambda were measured. The GHG (greenhouse gas) mass emissions and consequent GWP (Global Warming Potential) for different urban diving conditions were analyzed and presented. The results provided a better understanding of traffic related greenhouse gas emission profile in urban area and will contribute to the control of climate change

    Turbulence and particle acceleration in collisionless supernovae remnant shocks: II- Cosmic-ray transport

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    Supernovae remnant shock waves could be at the origin of cosmic rays up to energies in excess of the knee (E≃3⋅1015E\simeq3\cdot 10^{15} eV) if the magnetic field is efficiently amplified by the streaming of accelerated particles in the shock precursor. This paper follows up on a previous paper \citep{pell05} which derived the properties of the MHD turbulence so generated, in particular its anisotropic character, its amplitude and its spectrum. In the present paper, we calculate the diffusion coefficients, also accounting for compression through the shock, and show that the predicted three-dimensional turbulence spectrum k⊄S3d(k∄,k⊄)∝k∄−1k⊄−αk_\perp S_{3\rm d}(k_\parallel,k_\perp)\propto k_\parallel^{-1}k_\perp^{-\alpha} (with k∄k_\parallel and k⊄k_\perp the wavenumber components along and perpendicular to the shock normal) generally leads to Bohm diffusion in the parallel direction. However, if the anisotropy is constrained by a relation of the form k∄∝k⊄2/3k_\parallel \propto k_\perp^{2/3}, which arises when the turbulent energy cascade occurs at a constant rate independent of scale, then the diffusion coefficient loses its Bohm scaling and scales as in isotropic Kolmogorov turbulence. We show that these diffusion coefficients allow to account for X-ray observations of supernova remnants. This paper also calculates the modification of the Fermi cycle due to the energy lost by cosmic rays in generating upstream turbulence and the concomittant steepening of the energy spectrum. Finally we confirm that cosmic rays can produced an amplified turbulence in young SNr during their free expansion phase such that the maximal energy is close to the knee and the spectral index is close to 2.3 in the warm phase of the interstellar mediumComment: 13 pages, 4 figures, accepted for publication in Astronomy & Astrophysics main journa

    Traditional tales and imaginary contexts in primary design and technology: a case study

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    Working with contexts is a key component to design and technology activity and education. The most recent iteration of the national curriculum programme of study for design and technology, in England, sets out that children between the ages of 5 and 7 “should work in a range of relevant contexts” (DfE, 2013: 193); suggested contexts including “home and school, gardens and playgrounds, the local community, industry and the wider environment”. Whilst these are real world and familiar contexts, fictional contexts also provide opportunities for developing “creative spaces” in which to speculate and discuss. This intrinsic case study explores the work of two primary teachers’ development of a design and technology activity, where traditional tales provide the context. Children explore design problems and opportunities through the eyes of the Billy Goats Gruff, as they seek assistance to cross the river. Data was gathered through semi-structured interviews and document analysis of children’s design work. The case study reveals how multidisciplinary and imaginative approaches to teaching and learning in the primary classroom simulate and nurture design thinking, dialogue and critique

    Supporting campus based teaching with technology: web-based and groupware

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    This project explored the extent to which World Wide Web and groupware technologies (Lotus Notes was used in this project) could be used to improve support for teaching in a campus-based environment. The project was supported by the Teaching and Learning Quality Improvement Scheme (TLQIS) at the University of Salford and took place in the academic year 1997/98. Although concerned with the use of technologies, the emphasis of the project was placed onevaluation of the technologies in use in this particular context rather than their technical aspects per se. The impact of the use of technology is considered from the staff, student and organisational perspectives

    Coming Out, But Into What? Problematizing Discursive Variations of Revealing the Gay Self in the Workplace

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    There is a substantial mainstream literature on coming out in organizations, which investigates the positive effects for gay people of being out at work, but very few contributions that challenge the discourse of coming out. Taking as its starting point Butler's famous question ‘So we are out of the closet but into what?’, this paper problematizes coming out discourses in the workplace. We report on a study in which ten men were invited to talk about their coming out in the workplace. There were three main ways through which our participants constituted themselves as gay men when they talked about coming out: by defining themselves as, and admitting to, being gay; by introducing themselves as being in a gay relationship; and by adopting legitimate subject positions such as the Other, the different one, or the normal gay. Through our analysis, discussions and conclusions, we show how participants position themselves within different discursive variations, thus revealing the multiplicity of ‘the gay self’ and highlighting how coming out repeats and supports normative systems
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