22,377 research outputs found

    Uplift capacity of helical piles in thawing permafrost

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    This thesis focuses on the investigation of the effect of subsurface temperatures on the axial capacity of helical piles embedded in silty permafrost soils. The overall of goals of this thesis are (1) characterization of the impact of different environmental and loading conditions on the axial capacity of helical piles and (2) development of meaningful relationships on the physical processes in the subsurface, especially the interdependency of thermo-hydraulic behavior and the load-displacement behavior of piles. A balanced numerical and experimental campaign is carried out to understand the mechanisms that affect pile capacity with warming temperatures in a silt layer. A series of laboratory-scale pile experiments are performed, and the results are compared to predictions from theoretical methods. A numerical model is developed and validated against experimental results from the literature and is used to estimate load-displacement curves and uplift capacity of helical piles. The predictive numerical model is further used to probe more information about critical soil parameters that affect the capacity of piles in frozen soils. The laboratory-scale model consists of a double-helix helical pile embedded in an unsaturated Bonny silt layer inside a tank instrumented with an array of dielectric sensors to measure temperature, volumetric water content, and suction. The pile-soil system is frozen then thawed to different temperatures. Then, the pile is subjected to pull-out loading at constant displacement rates. The experimental program included seven tests performed at soil temperatures of -8˚C, -6˚C, -2˚C, -0.2˚C, and 17˚C. The experiment performed at -6˚C was repeated to investigate the impact of strain rate, and the experiment at 17˚C was repeated to understand the effect of thaw rate on pile axial capacity. The helical pile experiences brittle failures at displacements of about 0.5D for soil temperatures below -2˚C, where D is the helix diameter. Ductile behavior is evident when soil temperature is above -0.2˚C, as the peak load is reached at larger displacements of about 1D. Dielectric sensor measurements show that unfrozen water content decreases with temperature, with the most significant decrease occurring between 0 and -2˚C for the compacted silt. The axial capacity of helical piles increases linearly with decreasing temperatures below 0˚C, while it increases exponentially with decreasing degrees of saturation. For the experiments conducted at the same temperature but different strain rates, the slower pull-out rate results in higher axial capacity. Although the differences in pile capacity are very slight, this behavior is unexpected because viscous effects from the unfrozen water should increase the capacity at higher strain rates. Slight variations in temperature and unfrozen water content can explain this, indicating that those parameters may have a more significant effect on axial capacity. For the experiments conducted at the same strain rate but different thaw rates, the test with a faster thaw rate reaches a higher axial capacity. This may be due to more prevalent water migration in the test since slow thawing may lead to higher water contents at the center of the tank where the pile is located. Axial capacities from experiments are compared with predictions from theoretical helical pile capacity equations. Estimates of undrained shear strength from existing temperature correlations are employed in the theoretical calculations. It was concluded that predicted axial capacities show a good match with experimental results at temperatures below 0°C, but not for the fully thawed condition at room temperature. It is possible that for unfrozen soil, the undrained shear strength could not be predicted using the existing linear correlation since it is governed by other parameters, i.e., particle shape, pore size distribution, and water content, when ice is not present. The analyses and conclusions drawn from this study using the data sets from empirical observations, theoretical models, and numerical simulations will significantly contribute to design guidelines of helical piles installed in frozen soils and will be instrumental in adaptation strategies for sustainable development in cold regions.LimitedAuthor requested closed access (OA after 2yrs) in Vireo ETD syste

    Elite perceptions of the Victorian and Edwardian past in inter-war England

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    It is often argued by historians that members of the cultivated Elite after 1918 rejected the pre-war past. or at least subjected it to severe denigration. This thesis sets out to challenge such a view. Above all, it argues that inter-war critics of the Victorian and Edwardian past were unable to reject it even if that was what they felt inclined to do. This was because they were tied to those periods by the affective links of memory, family, and the continually unfolding consequences of the past in the present. Even the severest critics of the pre-war world, such as Lytton Strachey, were less frequently dismissive of history than ambivalent towards it. This ambivalence, it is argued, helped to keep the past alive and often to humanise it. The thesis also explores more positive estimation of Victorian and Edwardian history between the wars. It examines nostalgia for the past, as well as instances of continuity of practice and attitude. It explores the way in which inter-war society drew upon aspects of Victorian and Edwardian history both as illuminating parallels to contemporary affairs and to understand directly why the present was shaped as it was. Again, this testifies to the enduring power of the past after 1918. There are three parts to this thesis. Part One outlines the cultural context in which writers contemplated the Victorian and Edwardian past. Part Two explores some of the ways in which history was written about and used by inter-war society. Part Three examines the ways in which biographical depictions of eminent Victorians after 1918 encouraged emotional negotiation with the pas

    Modelling uncertainties for measurements of the H → γγ Channel with the ATLAS Detector at the LHC

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    The Higgs boson to diphoton (H → γγ) branching ratio is only 0.227 %, but this final state has yielded some of the most precise measurements of the particle. As measurements of the Higgs boson become increasingly precise, greater import is placed on the factors that constitute the uncertainty. Reducing the effects of these uncertainties requires an understanding of their causes. The research presented in this thesis aims to illuminate how uncertainties on simulation modelling are determined and proffers novel techniques in deriving them. The upgrade of the FastCaloSim tool is described, used for simulating events in the ATLAS calorimeter at a rate far exceeding the nominal detector simulation, Geant4. The integration of a method that allows the toolbox to emulate the accordion geometry of the liquid argon calorimeters is detailed. This tool allows for the production of larger samples while using significantly fewer computing resources. A measurement of the total Higgs boson production cross-section multiplied by the diphoton branching ratio (σ × Bγγ) is presented, where this value was determined to be (σ × Bγγ)obs = 127 ± 7 (stat.) ± 7 (syst.) fb, within agreement with the Standard Model prediction. The signal and background shape modelling is described, and the contribution of the background modelling uncertainty to the total uncertainty ranges from 18–2.4 %, depending on the Higgs boson production mechanism. A method for estimating the number of events in a Monte Carlo background sample required to model the shape is detailed. It was found that the size of the nominal γγ background events sample required a multiplicative increase by a factor of 3.60 to adequately model the background with a confidence level of 68 %, or a factor of 7.20 for a confidence level of 95 %. Based on this estimate, 0.5 billion additional simulated events were produced, substantially reducing the background modelling uncertainty. A technique is detailed for emulating the effects of Monte Carlo event generator differences using multivariate reweighting. The technique is used to estimate the event generator uncertainty on the signal modelling of tHqb events, improving the reliability of estimating the tHqb production cross-section. Then this multivariate reweighting technique is used to estimate the generator modelling uncertainties on background V γγ samples for the first time. The estimated uncertainties were found to be covered by the currently assumed background modelling uncertainty

    The Gradual Disappearance Of Financial Literacy In Today\u27s World. What Is Financial Literacy And Why Is It So Important? My Own Story Of Acquisition

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    There is a growing concern in this country that the middle class is disappearing and not in the way one would hope. Instead of families moving into a higher socio-economic class and being able to provide richer life experiences for themselves and their children, vast numbers are shifting to a lower socio-economic status level. The gap between the affluent and those barely eking out an existence is increasing at an alarming rate. This trend will directly affect who can successfully attend college and who will be available and capable to perform the blue-collar jobs that are vital to the continuation of our economy. Many of these jobs are becoming increasingly complex and sophisticated. While they may not require a college degree, they do require additional post-secondary training and expertise. Longer reaching concerns are that a dwindling middle class equates to a smaller tax base and contributes to a larger segment of the population that needs financial assistance. The productive management of money is part of a concept known as financial literacy. People that have money take this knowledge for granted. Somewhere along the line, whether it was at home, in school, or from personal experiences, successful people learned the value of earning money and using it thoughtfully and intentionally in order to achieve a future goal. No one disputes the fact that personal choices and discretion are parts of the picture. Imagine, however, that the environment in which you grew up did not contain earning possibilities. Perhaps you had to work without pay caring for your siblings, leaving no time to go out and earn your own money. Maybe your family was in the situation where everything that each family member earned was required to try to make ends meet. The result can be a feeling of ignorance and powerlessness around financial literacy and a lack of understanding the difference it could make in your life. This dissertation examines these issues. As a Scholarly Personal Narrative, it will also relate the story of my own journey of acquiring financial literacy and how that knowledge has affected my life. It concludes with a proposal that I created for teaching the concepts of financial literacy to underserved members of our society living at the lower socio-economic level. This education is important because understanding financial literacy can build self-confidence, empowerment, and purpose. This knowledge can also set an example that parents can pass on to their children and future generations. I believe this is one possible route toward breaking the cycle of poverty

    Strategies for Early Learners

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    Welcome to learning about how to effectively plan curriculum for young children. This textbook will address: • Developing curriculum through the planning cycle • Theories that inform what we know about how children learn and the best ways for teachers to support learning • The three components of developmentally appropriate practice • Importance and value of play and intentional teaching • Different models of curriculum • Process of lesson planning (documenting planned experiences for children) • Physical, temporal, and social environments that set the stage for children’s learning • Appropriate guidance techniques to support children’s behaviors as the self-regulation abilities mature. • Planning for preschool-aged children in specific domains including o Physical development o Language and literacy o Math o Science o Creative (the visual and performing arts) o Diversity (social science and history) o Health and safety • Making children’s learning visible through documentation and assessmenthttps://scholar.utc.edu/open-textbooks/1001/thumbnail.jp

    Metaphors of London fog, smoke and mist in Victorian and Edwardian Art and Literature

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    Julian Wolfreys has argued that after 1850 writers employed stock images of the city without allowing them to transform their texts. This thesis argues, on the contrary, that metaphorical uses of London fog were complex and subtle during the Victorian and Edwardian periods, at least until 1914. Fog represented, in particular, formlessness and the dissolution of boundaries. Examining the idea of fog in literature, verse, newspaper accounts and journal articles, as well as in the visual arts, as part of a common discourse about London and the state of its inhabitants, this thesis charts how the metaphorical appropriation of this idea changed over time. Four of Dickens's novels are used to track his use of fog as part of a discourse of the natural and unnatural in individual and society, identifying it with London in progressively more negative terms. Visual representations of fog by Constable, Turner, Whistler, Monet, Markino, O'Connor, Roberts and Wyllie and Coburn showed an increasing readiness to engage with this discourse. Social tensions in the city in the 1880s were articulated in art as well as in fiction. Authors like Hay and Barr showed the destruction of London by its fog because of its inhabitants' supposed degeneracy. As the social threat receded, apocalyptic scenarios gave way to a more optimistic view in the work of Owen and others. Henry James used fog as a metaphorical representation of the boundaries of gendered behaviour in public, and the problems faced by women who crossed them. The dissertation also examines fog and individual transgression, in novels and short stories by Lowndes, Stevenson, Conan Doyle and Joseph Conrad. After 1914, fog was no more than a crude signifier of Victorian London in literature, film and, later, television, deployed as a cliche instead of the subtle metaphorical idea discussed in this thesis

    Building body identities - exploring the world of female bodybuilders

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    This thesis explores how female bodybuilders seek to develop and maintain a viable sense of self despite being stigmatized by the gendered foundations of what Erving Goffman (1983) refers to as the 'interaction order'; the unavoidable presentational context in which identities are forged during the course of social life. Placed in the context of an overview of the historical treatment of women's bodies, and a concern with the development of bodybuilding as a specific form of body modification, the research draws upon a unique two year ethnographic study based in the South of England, complemented by interviews with twenty-six female bodybuilders, all of whom live in the U.K. By mapping these extraordinary women's lives, the research illuminates the pivotal spaces and essential lived experiences that make up the female bodybuilder. Whilst the women appear to be embarking on an 'empowering' radical body project for themselves, the consequences of their activity remains culturally ambivalent. This research exposes the 'Janus-faced' nature of female bodybuilding, exploring the ways in which the women negotiate, accommodate and resist pressures to engage in more orthodox and feminine activities and appearances

    Factors shaping future use and design of academic library space

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    COVID is having immediate and long-term impacts on the use of libraries. But these changes will probably not alter the importance of the academic library as a space. In the decade pre COVID libraries saw a growing number of visits, despite the increasing availability of material digitally. The first part of the paper offers an analysis of the factors driving this growth, such as changing pedagogies, diversification in the student body, new technologies plus tighter estates management. Barriers to change such as academic staff readiness, cost, and slow decision making are also presented. Then, the main body of the paper discusses emerging factors which are likely to further shape the use of library space, namely: concerns with student well-being; sustainability; equality, diversity and inclusion, and decolonisation; increasing co-design with students; and new technologies. A final model captures the inter-related factors shaping use and design of library space post COVID

    Supernatural crossing in Republican Chinese fiction, 1920s–1940s

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    This dissertation studies supernatural narratives in Chinese fiction from the mid-1920s to the 1940s. The literary works present phenomena or elements that are or appear to be supernatural, many of which remain marginal or overlooked in Sinophone and Anglophone academia. These sources are situated in the May Fourth/New Culture ideological context, where supernatural narratives had to make way for the progressive intellectuals’ literary realism and their allegorical application of supernatural motifs. In the face of realism, supernatural narratives paled, dismissed as impractical fantasies that distract one from facing and tackling real life. Nevertheless, I argue that the supernatural narratives do not probe into another mystical dimension that might co-exist alongside the empirical world. Rather, they imagine various cases of the characters’ crossing to voice their discontent with contemporary society or to reflect on the notion of reality. “Crossing” relates to characters’ acts or processes of trespassing the boundary that separates the supernatural from the conventional natural world, thus entailing encounters and interaction between the natural and the supernatural. The dissertation examines how crossing, as a narrative device, disturbs accustomed and mundane situations, releases hidden tensions, and discloses repressed truths in Republican fiction. There are five types of crossing in the supernatural narratives. Type 1 is the crossing into “haunted” houses. This includes (intangible) human agency crossing into domestic spaces and revealing secrets and truths concealed by the scary, feigned ‘haunting’, thus exposing the hidden evil and the other house occupiers’ silenced, suffocated state. Type 2 is men crossing into female ghosts’ apparitional residences. The female ghosts allude to heart-breaking, traumatic experiences in socio-historical reality, evoking sympathetic concern for suffering individuals who are caught in social upheavals. Type 3 is the crossing from reality into the characters’ delusional/hallucinatory realities. While they physically remain in the empirical world, the characters’ abnormal perceptions lead them to exclusive, delirious, and quasi-supernatural experiences of reality. Their crossings blur the concrete boundaries between the real and the unreal on the mental level: their abnormal perceptions construct a significant, meaningful reality for them, which may be as real as the commonly regarded objective reality. Type 4 is the crossing into the netherworld modelled on the real world in the authors’ observation and bears a spectrum of satirised objects of the Republican society. The last type is immortal visitors crossing into the human world. This type satirises humanity’s vices and destructive potential. The primary sources demonstrate their writers’ witty passion to play with super--natural notions and imagery (such as ghosts, demons, and immortals) and stitch them into vivid, engaging scenes using techniques such as the gothic, the grotesque, and the satirical, in order to evoke sentiments such as terror, horror, disgust, dis--orientation, or awe, all in service of their insights into realist issues. The works also creatively tailor traditional Chinese modes and motifs, which exemplifies the revival of Republican interest in traditional cultural heritage. The supernatural narratives may amaze or disturb the reader at first, but what is more shocking, unpleasantly nudging, or thought-provoking is the problematic society and people’s lives that the supernatural (misunderstandings) eventually reveals. They present a more compre--hensive treatment of reality than Republican literature with its revolutionary consciousness surrounding class struggle. The critical perspectives of the supernatural narratives include domestic space, unacknowledged history and marginal individuals, abnormal mentality, and pervasive weaknesses in humanity. The crossing and supernatural narratives function as a means of better understanding the lived reality. This study gathers diverse primary sources written by Republican writers from various educational and political backgrounds and interprets them from a rare perspective, thus filling a research gap. It promotes a fuller view of supernatural narratives in twentieth-century Chinese literature. In terms of reflecting the social and personal reality of the Republican era, the supernatural narratives supplement the realist fiction of the time
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