2,117 research outputs found
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Incremental profile ring rolling with axial and circumferential constraints
© 2017 If profile ring rolling could be achieved without part-specific tooling, significant savings in material, energy and downstream processing could be realised. One approach, ‘incremental ring rolling’ previously suffered difficulties controlling material flow, resulting in multiple form errors. Inspired by studying an expert using a potter's wheel, two additions to this process are proposed; the use of axial and circumferential constraints. A 12-axis ring rolling machine has been built to demonstrate these process enhancements, producing metal rings up to 1 m in diameter. The production of both rectangular and L-shape rings is examined, showing significant improvements in ring cross-sectional form and circularity.The first author was supported by an EPSRC I-Case Studentship (12220703), with Primetals Technologies Ltd. Prof. Allwood was supported by EPSRC grant EP/K018108/1
Viability and performance of demountable composite connectors
AbstractMaterial production, and associated carbon emissions, could be reduced by reusing products instead of landfilling or recycling them. Steel beams are well suited to reuse, but are difficult to reuse when connected compositely to concrete slabs using welded studs. A demountable connection would allow composite performance but also permit reuse of both components at end-of-life. Three composite beams, of 2m, 10m and 5m length, are constructed using M20 bolts as demountable shear connectors. The beams are tested in three-, six- and four-point bending, respectively. The former two are loaded to service, unloaded, demounted and reassembled; all three are tested to failure. The results show that all three have higher strengths than predicted using Eurocode 4. The longer specimens have performance similar to previously published comparable welded-connector composite beam results. This suggests that demountable composite beams can be safely used and practically reused, thus reducing carbon emissions
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Implementing material efficiency in practice: A case study to improve the material utilisation of automotive sheet metal components
© 2019 There is an opportunity to reduce the amount of sheet metal currently used to manufacture automotive components, despite the available cost and CO2 savings, the automotive industry has not realised the full potential of these saving opportunities. To understand why, a practical case study was set up with an automotive manufacturer. A cross-functional team was established with the scope to make changes to five components using a structured design process to improve material efficiency. The trial identified realistic opportunities to improve material utilisation by 20%pts, and save £9million and 5 kilotonnes of CO2 annually. The greatest saving opportunities were found early in the product development cycle, before the production method is determined by component geometry. Of these, 3%pts were actually implemented on the production vehicle, saving £1.8million and 1.5 kilotonnes of CO2 annually. The case study identified significant barriers to implementing material efficiency strategies in an industrial setting. To overcome these barriers material utilisation should be considered early in the product design process and high in the vehicle platform hierarchy. As a result of this investigation, new business processes are being generated to support design for material utilisation at the automotive manufacturer. This case study approach should be considered to increase implementation for other aspects of material demand reduction.EP/N02351X/
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Controls on development and diversity of Early Archean stromatolites
The ≈3,450-million-year-old Strelley Pool Formation in Western Australia contains a reef-like assembly of laminated sedimentary accretion structures (stromatolites) that have macroscale characteristics suggestive of biological influence. However, direct microscale evidence of biology—namely, organic microbial remains or biosedimentary fabrics—has to date eluded discovery in the extensively-recrystallized rocks. Recently-identified outcrops with relatively good textural preservation record microscale evidence of primary sedimentary processes, including some that indicate probable microbial mat formation. Furthermore, we find relict fabrics and organic layers that covary with stromatolite morphology, linking morphologic diversity to changes in sedimentation, seafloor mineral precipitation, and inferred microbial mat development. Thus, the most direct and compelling signatures of life in the Strelley Pool Formation are those observed at the microscopic scale. By examining spatiotemporal changes in microscale characteristics it is possible not only to recognize the presence of probable microbial mats during stromatolite development, but also to infer aspects of the biological inputs to stromatolite morphogenesis. The persistence of an inferred biological signal through changing environmental circumstances and stromatolite types indicates that benthic microbial populations adapted to shifting environmental conditions in early oceans
Modelling the embodied carbon cost of UK domestic building construction: Today to 2050
The construction of new domestic properties contributes 2% of UK territorial greenhouse gas (GHG) emissions. The UK government aims to increase construction of new homes in England by almost a third, to 300,000 per year by the mid-2020s, whilst simultaneously reducing emissions in line with its net zero 2050 commitment. In this paper, for the first time, the upfront embodied carbon cost of constructing domestic properties in the UK by 2050 is quantified. A bottom-up analysis modelling seven domestic building typologies was used, with the material use for each based on current UK practice. Possible interventions to reduce the embodied carbon cost are then analysed. The results show that maintaining today's levels of construction will use the remaining 2050 carbon budget apportioned to house building (160 MtCO 2e) by 2036, and cause a substantial increase in domestic floor area per capita. However, construction could reduce and cease entirely by 2035 without reducing today's living floor area per capita (37.5 m 2), resulting in a substantially reduced cumulative embodied carbon of 88 MtCO 2e by 2050. Increasing living floor area per capita to the EU average of 40.5 m 2, can be achieved within the carbon budget and with zero emissions by 2050. In contrast, increasing house building to government targets will result in double the cumulative emissions than the budget allows. A number of carbon reduction interventions were then investigated. It was found that of to 75% embodied carbon savings can be achieved by simultaneously changing the typology share, increasing material efficiency, increasing conversion from non-residential buildings and increasing the use of timber for structural purposes.</p
Annex 1 - Glossary
This glossary defines some specific terms as the Lead Authors intend them to be interpreted in the context of this report
Study of diffusion weighted MRI as a predictive biomarker of response during radiotherapy for high and intermediate risk squamous cell cancer of the oropharynx: The MeRInO study
Introduction and background:
A significant proportion of patients with intermediate and high risk squamous cell cancer of the oropharynx (OPSCC) continue to relapse locally despite radical chemoradiotherapy (CRT). The toxicity of the current combination of intensified dose per fraction radiotherapy and platinum based chemotherapy limits further uniform intensification. If a predictive biomarker for outcomes from CRT can be identified during treatment then individualised and adaptive treatment strategies may be employed.
Methods/design:
The MeRInO study is a prospective observational imaging study of patients with intermediate and high risk, locally advanced OPSCC receiving radical RT or concurrent CRT Patients undergo diffusion weighted MRI prior to treatment (MRI_1) and during the third week of RT (MRI_2). Apparent diffusion coefficient (ADC) measurements will be made on each scan for previously specified target lesions (primary and lymph nodes) and change in ADC calculated. Patients will be followed up and disease status for each target lesion noted. The primary aim of the MeRInO study is to determine the threshold change in ADC from baseline to week 3 of RT that may identify the sub-group of non-responders during treatment.
Discussion:
The use of DW-MRI as a predictive biomarker during RT for SCC H&N is in its infancy but studies to date have found that response to treatment may indeed be predicted by comparison of DW-MRI carried out before and during treatment. However, previous studies have included all sub-sites and biological sub-types. Establishing ADC thresholds that predict for local failure is an essential step towards using DW-MRI to improve the therapeutic ratio in treating SCC H&N. This would be done most robustly in a specific H&N sub-site and in sub-types with similar biological behaviour. The MeRInO study will help establish these thresholds in OPSCC
Quality of life in children with primary antibody deficiency.
Primary antibody deficiency disorders (PADs) can have an excellent outlook if diagnosed early and treated appropriately, but require lifelong treatment with immunoglobulin replacement. Some carry risks of inflammatory complications even with optimal treatment. Quality of life (QoL) and the psychological impact of PADs has been relatively little studied, particularly in children. The purpose of this study was to evaluate QoL and psychological impact in a large group of children affected by a range of PADs, as well as a group with transient hypogammaglobulinemia of infancy (THI). Both parental and, where appropriate, child ratings, were collected using standardised questionnaires (PedsQL and SDQ). Higher rates of psychological difficulties, particularly emotional and peer-relationship difficulties were found in children with PAD when compared with healthy controls. Quality of life was poorer than in healthy controls, and also worse than in children affected by diabetes mellitus. Variations in QoL and the degree of psychological difficulties were found between specific diagnostic groups, with children affected by THI being amongst those with the lowest scores for QoL. Further studies are needed to corroborate and extend these findings, but this study confirms previous findings that primary antibody deficiency has a significant impact on quality of life and psychological well-being, and additionally suggests that the impact varies according to severity of the underlying condition. For those with significant difficulties psychological intervention at an early stage may be beneficial
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