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How do we go from here? : the consumption of the car and the pursuit of a low carbon automobilityKershaw, J. E. January 2015 (has links)
Although the environmental imperative compels us to search for a low carbon system of mobility, contemporary society seemingly necessitates a low carbon automobility. The costs and impracticalities of low carbon vehicles are well documented, and although the cultural and semiotic nature of the car means that it has always been more than just a means of transport, less is known about how socio-cultural mores regarding the car might impact upon the transition to low carbon motoring. Because cars carry people, then they inevitably carry experiences and meanings too. However, a shift from conventional internal combustion-engined vehicles to more low carbon forms of propulsion, such as electric or hybrid vehicles, suggests that the nature – et ergo our experiences and perceptions – of the car will necessarily change. It is therefore desirable to investigate the contemporary ‘consumption’ of the car, not only as personal transport but also as status symbol, cultural artefact and experience, to assess how such a socio-cultural consumption might apply to low carbon vehicles and so ascertain the subsequent potential for a holistic low carbon automobility as part of a sustainable transport policy. A suite of methods was employed to investigate if or how contemporary automobilities can aspire to a low carbon automobility, or whether the everyday socio-cultural ‘consumption’ of the car might preclude a transition to low carbon vehicles. The notions of affect and/or non-representational theory were appropriated as a philosophical framework to look beyond a seemingly default postmodern ‘car-as-representation’ approach to the consumption of the car and so begin to explore a deeper, perhaps even subconscious, regard for the car. In addition, opinion was sought from stakeholders within the low carbon vehicle sector as to the technologies within, the prospects for, and the efficacy of, UK low carbon vehicle policy and its facilitation thereon, and also with a sample of EV drivers as to their experiences of electric cars. Responses to an initial online questionnaire appeared to deny any status or regard for the car beyond its utility. However, subsequent semi-structured interviews with motorists conducted (mostly) in their cars contradicted these findings, with a variety of expressed feelings – pride, empowerment, fortune – suggesting a deeper, subconscious regard for, reading of, and connection with, the car than is immediately apparent. Similarly, the utility of the electric car was transcended, this time by feelings of ‘greenness’ and ‘calm’ expressed by EV drivers. A stated amenability and aspiration by those interviewed for low carbon vehicles contrasted with an aspiration for sporty and prestige cars, suggesting an ingrained or innate idea as to what constitutes a truly desirable car. The more cultural facets of the car explored during focus group discussions established a connection between a car’s cultural representation and its meaning. Interviews with low carbon vehicle stakeholders suggest that while UK low carbon vehicle policy is broadly effective, is not as efficacious as it could be, in that itinerate market-led aspirations lack the fixity and certainty, in terms of both infrastructure and policy, that investors and consumers require, especially given a high entry price, the promise of lower running costs notwithstanding. In establishing where ‘here’ is regarding the consumption of the car and the implementation of a low carbon vehicle policy, this research provides a new perspective upon the appetite and potential for a transition to a future low carbon automobility, and shows the efficacy of appropriating the notions of affect and non-representational theory to a more holistic consumption of the car.
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The effect of niobium and vanadium on the microstructure of rapidly-cooled controlled-rolled, low carbon steelBayley, H. K. January 1979 (has links)
No description available.
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Transient fatigue crack growth in a structural steelDamri, Daniel January 1991 (has links)
No description available.
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Developing material selection strategies to improve the embodied impacts of buildingsWatson, Natasha January 2016 (has links)
The embodied environmental and socioeconomic impacts of building construction are rarely considered within industry. Renewable and certified resources will continue to provide a viable low impact supply chain for construction, yet the use of such low impact building materials (LIBM) remains a small proportion of the current market. Structural engineers should be encouraged to use LIBM and consider the impacts of building construction, and so the research aim was to create an informed and responsible approach for structural engineers to reduce the embodied impacts of their projects. The limited amount of academic literature on the consideration of embodied impacts within construction and the use of LIBM prompted a two-phase research methodology. The first Problem Exploration phase developed a rich understanding of the current context of embodied impacts within construction through an analysis of data gathered from an online questionnaire and semi-structured interviews. The findings identified three key aspects to consider when developing an Embodied Impact Reduction Approach (EIRA); the alignment of the project-life cycle with influence, the limitation of time and costs, and the importance of support and education within the approach created. The second Action phase developed EIRA using the findings and supplementary data gathered from focus groups, which highlighted that EIRA should be flexible so as to be relevant to the breadth of projects that BuroHappold Engineering, who partially sponsored the research, work on. EIRA runs parallel to the RIBA Plan of Work, adapting to the different objectives, level of detail and information available at each project stage. Three components were developed; the Material Design Sheets, Carbon Calculator, and the Option Appraisal Support Technique (tOAST). tOAST was implemented on five projects to test its applicability, which identified that greater understanding of embodied impacts plus their relative importance to each other is required. Another key issue was the availability of appropriate embodied environmental data.
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An environmental life cycle assessment of energy systems leading to a pathway for a low carbon economyKelly, Katharine Anne January 2013 (has links)
In 2008, the UK Government enforced the target to reduce the UK carbon account for the year 2050 to at least 80% less than the 1990 baseline. In order to meet this ambitious target it is widely thought that the UK energy future should be ‘electrified’ as a suite of low carbon generation technologies provide ever increasing proportions of electricity supply. This work has identified and investigated two technologies that could make significant contributions to low carbon power supply in the UK; that of industrial combined heat and power, CHP, and tidal power. Life cycle case studies were completed on an existing UK CHP plant and the Severn Barrage scheme as it was proposed until 2010. The Severn Barrage assessment has shown that the lifetime environmental impact is dominated by the operation stage. This is contrary to previously published studies, which have underestimated (Parsons Brinckerhoff Ltd; Black and Veatch Ltd; 2010)(Roberts 1982)(Spevack, Jones and Hammond 2011) or even ignored (Black & Veatch 2007)(Woollcombe-Adams, Watson and Shaw 2009)the contribution from this life stage. Furthermore, the results have demonstrated that the impact intensity of power from the Barrage is almost entirely reliant on that of the National Grid mix which provides the operational power required. It has been shown a large improvement to the impact of the operation stage can be made by removing the electricity demand for ‘flood pumping’. However, even without ‘flood pumping’, the impact of the power demand for plant operation will dominate. Hence the greatest improvements to the schemes lifetime impact can be made via the National Grid mix itself. The industrial CHP assessment has shown that there are large impact savings available from widespread implementation against the current and the baseline National Grid mixes. However, even if it is assumed that units are exclusively bio-gas fuelled, the carbon intensity of the power generated is very likely to exceed that of the low carbon Grid mix by 2050. The discussion shows that the interactive roles that these two technologies could play, with each other and the evolving Grid mix, on the pathway to 2050 is, however, more complex than simply considering the isolated impact intensity. The commissioning of the Severn Barrage could mark the point at which the carbon intensity of the National Grid falls below that of CHP. However because the carbon intensity of the plant is reliant on the national power supply, it is argued that further CHP implementation should only be stopped if there is a suitable low carbon and low impact alternative that can fill the capacity gap. This thesis concludes that to fear that today’s CHP schemes could represent a technology ‘lock-in’ in the long term future is to underestimate the role the technology has in the current and more short term future Grid mix. The work presented demonstrates the importance of life cycle thinking in the development of a low impact energy strategy. The discussion has also shown the importance of scenarios in assessing the requirements for such an ambitious change. The pursuit of change implies that the future is necessarily dynamic. The work has illustrated that scenario thinking allows exploration of potential strategy decisions and hence, is essential to having confidence in the decisions made.
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Deoxidation mechanisms in liquid steelKay, Helen January 1996 (has links)
Quantitative chemical and scanning electron microscopical techniques have been employed to investigate the deoxidation kinetics and changes in oxidation product morphology in low carbon steel melts. The techniques have been used to study the deoxidation processes associated with aluminium, titanium, silicon, zirconium and a calcium-aluminium alloy. After the addition of the deoxidant, the total oxygen concentrations of all melts rapidly decreased corresponding with a decrease in the size and number of inclusions observed. This continued to a plateau level of total oxygen concentration and mean inclusion diameter. Samples removed from the melts prior to deoxidation were found to contain globular MnO-FeO inclusions. It was discovered that the morphological sequence for single element deoxidants involved a progressive evolution from liquid globular to solid spherical inclusions followed by polyhedral, dendritic and coralline morphologies. Finally, sintered agglomerates were formed when inclusion clusters collapsed. The extent to which the oxidation products went down the sequence depended on: the dissolution characteristics of the deoxidant; the thermodynamic affinity of the deoxidant for oxygen in the melt; the inclusion/melt interfacial energy characteristics; the refractoriness of the oxidation products and intermediate compounds; and the degree of turbulence experienced by the melt. Explanations have been postulated which elucidate the behaviour of the different deoxidants, as not all displayed the whole morphological sequence. Silicon deoxidation produced spherical silicates, whereas the zirconia inclusions were either spherical or dendritic and the titanium oxidation products had spherical or polyhedral morphologies. Aluminium exhibited all morphologies in the sequence. Deoxidation with the calcium-aluminium alloy was found to have preceded by a two stage process. The initial stage was dominated by the formation of aluminium rich solid oxides followed by the progressive reduction by calcium, resulting in an adhesive liquid calcium-aluminate surface coating. The role of refractory crucible as a collecting surface for the capture and removal of deoxidation products from the melt was investigated, which confirmed that the inclusions were generally incorporated into the low melting point matrix phases. Turbulence also increased the probability that emergence would take place at these capture sites.
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Deformation and recrystallisation in low carbon steelsAlmojil, Marwan January 2010 (has links)
The annealing behaviour, including studies of recrystallisation kinetics and development of crystallographic texture, of two low carbon steels after different cold rolling reductions have been investigated using Optical Microscopy (OM), Electron Back-Scatter Diffraction (EBSD) and Transmission Electron Microscopy (TEM). The primary recrystallisation behaviour of 20, 50, 70 and 90% cold rolled Interstitial Free (IF) and High Strength Low Alloy (HSLA) steels was studied. The HSLA was initially processed to give a volume fraction of about 0.2 of fine pearlite colonies, which acted as mechanically hard particles. The presence of such particles on the HSLA steel significantly reduced the temperature needed for recrystallisation by enhancing the recrystallisation and acting as nucleation sites by the Particle Stimulated Nucleation (PSN) mechanism. The inhomogeneous deformation and the local orientation changes introduced in the neighbourhood of the carbide particles (i.e. the particle deformation zone) were observed using TEM and selected area electron diffraction. The JMAK model was used to analyse the recrystallisation kinetics of the two steels. The experimental data plotted according to the JMAK model could be represented by straight lines with a JMAK exponent n falling in the range from 1.4 to 2.0. The development of crystallographic textures after cold rolling reductions and subsequent recrystallisation has been investigated. The texture development is shown to be largely dependent on the rolling reduction. With increasing rolling reduction, the annealing texture show gradual intensification of α- and γ-fibre components. However, the intensity of both fibres is weaker in the HSLA steel. Despite the dominance of PSN in HSLA steel, the recrystallisation textures were similar to that of the rolling textures with weaker intensity of both fibres. To help clarify the reasons for that, in-situ EBSD experiments of recrystallising HSLA steel deformed to 50% and 70% have been carried out. It shows that the formation of the nucleus seems to occur within the deformation zones in regions away from the particle surface leading to recrystallisation textures similar to that of the rolling textures (i.e. both α- and γ-fibre exist). The validity of this assumption has been confirmed by the use of Monte Carlomodelling. This model was used to simulate, in general way, and study the phenomenon of PSN during the recrystallisation process. The simulation shows the discontinuous evolution of the subgrains in the deformation zone to form recrystallisation nuclei around the particle. It shows also the subsequent growth of these nuclei to consume the matrix region around the particle. The simulation results are shown to match with the experimentally observed features of the recrystallisation phenomena in low carbon steel containing coarse cementite particles.
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Facilitating Low-Carbon Living? A Comparison of Intervention Measures in Different Community-Based InitiativesSchäfer, Martina, Hielscher, Sabine, Haas, Willi, Hausknost, Daniel, Leitner, Michaela, Kunze, Iris, Mandl, Sylvia January 2018 (has links) (PDF)
The challenge of facilitating a shift towards sustainable housing, food and mobility has
been taken up by diverse community-based initiatives ranging from "top-down" approaches in
low-carbon municipalities to "bottom-up" approaches in intentional communities. This paper
compares intervention measures in four case study areas belonging to these two types, focusing
on their potential of re-configuring daily housing, food, and mobility practices. Taking up critics
on dominant intervention framings of diffusing low-carbon technical innovations and changing
individual behavior, we draw on social practice theory for the empirical analysis of four case studies.
Framing interventions in relation to re-configuring daily practices, the paper reveals differences
and weaknesses of current low-carbon measures of community-based initiatives in Germany and
Austria. Low-carbon municipalities mainly focus on introducing technologies and offering additional
infrastructure and information to promote low-carbon practices. They avoid interfering into residents¿
daily lives and do not restrict carbon-intensive practices. In contrast, intentional communities
base their interventions on the collective creation of shared visions, decisions, and rules and thus
provide social and material structures, which foster everyday low-carbon practices and discourage
carbon-intensive ones. The paper discusses the relevance of organizational and governance structures
for implementing different types of low-carbon measures and points to opportunities for broadening
current policy strategies.
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Travel and tourism (‘travelism’) in the low-carbon economy : the role of public policy in accelerating decarbonisation over the next four decadesVorster, Shaun 12 1900 (has links)
ENGLISH ABTRACT: This study considers the policy options for the accelerated decarbonisation of travel and tourism
(or ‘travelism’) over the next four decades. The concept of ‘travelism’ approaches aviation, travel
and tourism as an integrated value chain. The value chain’s carbon footprint and possible
mitigation options (or ‘wedges’) are analysed through the lenses of the three pillars of
sustainable development (i.e. social, environmental and economic values), which represent the
core of a conceptual model for green, low-carbon travelism growth. This model provides a
systems perspective on the ‘what’, ‘why’ and ‘how’ of the envisioned low-carbon transformation.
Travelism is both a vector and victim of climate change, and simultaneously makes a significant
economic and social contribution to society at large. ‘Doing nothing’ to face up to the challenges
of climate change is therefore not an option, nor is the ‘slowing down’ of travelism demand. Yet,
the approaching clash of trajectories between business-as-usual travelism growth and climate
stabilisation goals provides strong motivation for ‘decoupling’ (i.e. decarbonising travelism).
Travelism has to contribute its fair share to keeping global temperature increase to below 2 °C
above pre-industrial levels, while allowing development to proceed sustainably.
Consequently, mitigation ‘wedges’ are identified for three travelism sub-clusters with quantifiable
carbon footprints (i.e. accommodation, land transport and air transport). A combination of public
policy approaches (i.e. information-based, incentive-based and directive-based) are identified
that can help to overcome implementation barriers for those cost-efficient mitigation options with
significant carbon abatement potential and other sustainable-development co-benefits.
In the accommodation cluster, green building design, energy-efficiency measures and
renewable-energy deployment are priorities. In the land transport cluster, passenger modal
shifts, more efficient vehicles and low-carbon fuels as well as improved public transport in
‘green cities’ represent the most promising mitigation options. In both these clusters, integrated
planning and alignment with other policy domains, best-practice sharing, consumer education,
vertical supply chain partnerships and a mix of government incentives and regulatory standards
are required.
In the air transport cluster, mitigation options related to operational, infrastructural and
technology-driven efficiency improvements represent the ‘low-hanging fruit’ for the next two
decades. However, once this emissions reduction potential has been optimised, only two
(known) game changers remain: firstly, the development and commercialisation of secondgeneration
(i.e. sustainable) drop-in biofuels as substitute for high-carbon kerosene jet fuel, and,
secondly, the introduction of a market-based mechanism (MBM). Based on the analysis of the technical and financial feasibility, sustainability and scalability of
the biofuels mitigation wedge, it is concluded that there is no either/or choice between drop-in
biofuels and MBMs. A risk management approach requires pursuance of both. Creating a global
aviation biofuels industry will be no small endeavour, though. It will require a package of public
policies, funding and partnerships at various stages of the technology life cycle and throughout
a long value chain. Besides carbon abatement, local economic development and job creation
co-benefits in developing and emerging economies are also achievable. An MBM for aviation
emissions should ideally be designed as a global, ‘open’ emissions-trading scheme that (i)
provides a progressive price incentive for the uptake of sustainable biofuels as well as
pursuance of the other mitigation options, and (ii) creates flexibility for the aviation sector to
offset its unavoidable emissions with lower-cost emissions reductions from other economic
sectors.
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Flexible formwork for concrete structuresOrr, John January 2012 (has links)
Concrete, our most widely used construction material, is a fluid that offers the opportunity to economically create structures of almost any geometry. Yet this unique fluidity is seldom capitalised on, with concrete instead being cast into rigid prismatic moulds to create high material use structures with large carbon footprints. Our rate of concrete consumption means that cement manufacture alone is estimated to account for some 5% of global Carbon Dioxide emissions. This dissertation shows that by replacing conventional orthogonal moulds with a flexible system comprised primarily of high strength, low cost fabric sheets, the fluidity of concrete can be utilised to create structurally optimised concrete structures. Flexible formwork therefore has the potential to facilitate the change in design and construction philosophy that will be required for a move towards a less material intensive, more sustainable, construction industry. Optimisation and design processes developed in this thesis show that material savings of up to 40% are possible in flexibly formed concrete beams. Full scale structural testing of these processes is undertaken to verify the flexural and shear behaviours of non-prismatic elements. This is supported by further experimental and theoretical investigations into the durability of concrete cast in a permeable, flexible mould. Detailed analysis is provided alongside practical guidance for designers. Coupled with innovation in design and analysis techniques, flexible formwork is shown to provide a globally accessible method for the construction of low carbon, materially efficient and architecturally interesting concrete structures. Recognising the impact construction has on the environment, design philosophies centred around the need to put material where it is required are becoming increasingly desirable. This can now be achieved by replacing rigid formworks with systems comprised of flexible sheets of fabric. This is a step change in the way we think about our new concrete structures.
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