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Land Beneath the Water: Narratives of the Keowee-Toxaway Project in Appalachian South CarolinaGregory, Austin 01 May 2019 (has links) (PDF)
In 1965, Duke Power announced the construction of a series of dams along the Keowee and Little rivers in Oconee County, South Carolina. The dams would create water reservoirs for one of the largest hydro-electric and nuclear power facilities in the nation. The dominant narrative focuses on the recreational activities, power generation, and economic development facilitated by the creation of lakes Jocassee and Keowee. However, residents of the Keowee and Jocassee valleys had to be removed, a process that started years earlier when Duke Power began serious land purchasing efforts. This study focused on discovering diverse narratives from people that were displaced or otherwise affected by the lakes. In doing so, made comparisons with other projects on displaced populations in Appalachia, examined the beneficiaries of the project, the treatment of locals, and how Duke Power and local government presented the project through local media.
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[pt] ESTUDO DO COMPORTAMENTO DINÂMICO DE UMA FURADEIRA RADIAL DE BANCADA / [en] STUDY OF DYNAMIC PERFORMANCE OF A BENCH RADIAL DRILLEDIVAL PONCIANO DE CARVALHO 24 November 2011 (has links)
[pt] Este trabalho se propõe a estudar o comportamento de máquina operatriz sob condições reais de operação, tendo em vista sua estabilidade de funcionamento. É analisado o efeito da variação da força de corte sobre a estrutura elástica de uma Furadeira Radial de Bancada, através da interpretação da Curva de Ressonânica, do Lugar Geométrico de Resposta Harmônica e do Diagrana de Estabilidade. E este último indica as faixas de velocidade de operação onde não há risco de instabilidade, em função do diâmetro e do avanço da broca. No final, é apresentada uma proposta de Teste de Aceitação para Máquinas Operatrizes, englobando aspectos dinâmicos e construtivos. / [en] The behavior of a machine tool, under real cutting conditions, here is studied, mainly considering its
dynamic stability. The effect of the cutting force variation on the elastic structure of Radial Drilling Machine is analyzed by the Ressonance Curve, the Harmonic Response Locus and Stability Chart. This chart indicates the chatter-free rotational speed range, according to the tool diameter and infeed per revolution. An acceptance test for Machine Tools is proposed at the end, considering dynamic and constructive aspects.
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[pt] ALGUNS ASPECTOS SOBRE BOMBAS CENTRÍFUGAS RADIAIS / [en] SOME ASPECTS ABOUT RADIAL CENTRIFUGAL PUMPSNELSON MARTIN 02 August 2012 (has links)
[pt] Apresenta-se, neste estudo, quatro análises sobre bombas centrífugas radiais:
a) Determinação de curvas características teóricas;
b )Obtenção de curvas características de rotores usinados;
c) Influência do estreitamento do rotos nas curvas características
d) Efeitos da rugosidade do rotor nas curvas características experimentais.
Utilizando-se de dois modelos de bombas Dancor, determinaram-se curvas características nos planos vazão-altura manométrica, vazão –potência efetiva e vazão-rendimento.
Escolhendo-se os coeficientes, necessários ao calculo teórico de uma curva característica, dentro de critérios estabelecidos, consegue-se a aproximação entre as curvas teóricas e experimentais de uma bomba centrífuga radial.
Ao usinar-se o rotor de uma bomba, as curvas características para o novo diêmetro deixam de obedecer às leis de semelhança, pois há variação do rendimento, principalmente na zona de trabalho de bomba. Determinou-se curvas com redução de 3,7 por cento e 11,1 por cento do diâmetro do rotor normal.
Com o estreitamento do rotor há, na realidade, variações nos triângulos de velocidade, em virtude das perdas que acontecem na saída do rotor e, conseqüentemente, alterando as curvas características. Ensinando-se rotores com larguras 23 por cento menores do que o rotor normal.
A rugosidade também altera as curvas características deslocando o ponto máximo rendimento para a esquerda (menor vazão e menor altura manométrica), num rotor 60 por cento mais rugoso do que o normal. / [en] The present work deals with theoretical and experimental considerations abount radial centrifugal pumps. Four analysis are made. They are:
a) determination of theoretical characteristic curves;
b) determination of characteristic curves of impellers with reduced diametes;
c) influence of the narrowing of, impeller upon the characteristic experimental curves.
Curves were determined in the capacity-head, capacity-effective power and capacity-efficiency the utilization of two models of Dancor pumps.
Once the choice of the coeffcients needed for the theoretical calculation of a characteristic curve is made according to established of a characteristic curve is made according to establishe criteria, an approximation between the theorical and experimental curves a radical centrifugal pump is obtained.
The determination of curves with cuts with 3.7 per cent and 11.1 per cent of the full impeller has been made. IT has been observed that when a pump impeller is cut the characteristic curves for the new diameter do not follow any more the laws of similarity because the is a variation in the efficiency mainly in the work zone of the pump.
Assays have benn made with implellers that had widths 23 per cent less than the full ones. It has benn observed that with the narrowing of the impeller there are actually alterations in the triangles of velocity due to losses that occurin the exit of the impeller. On that acount. The characteristic are altered.
Assays have also benn made with an impeller with 60 per cent more rugosity than a full one. It has benn shown is this study that the increase in rugosity causes alterations in the characteristic curves by shifting the best point of effciency to the left (lower capacity and lower head).
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Home In DiasporaAydin, Paulina January 2020 (has links)
What happens when home moves and has to resettle somewhere else because of contemporary invocations of diaspora? In a series of meaningful displacements one might have multiple homes with different reasons for maintaining some form of attachment to each. Through a semi-structured approach, letting narratives unfold as they come up, I ask: What did you leave? What did you meet? What did you get and give? What could that be? An architectural alphabet evolves that tells stories, comes with things and moments but perhaps most important questions the habitual and the culturally specific. How can we understand what a home is if I do not ask what a home was, is for someone else or could be? And not only through the homes we idealize but through the displaced homes that actually have to meet ours. Could this alphabet be used to provoke the limited one we have today and help us towards the prospect of choice by imagining a future whereupon there could, or maybe simply should, be so many more? More to be used to rethink and deviate from a standard mark that negates a past for some and make the transition more than a continuum for others.
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Slope stability assessment through field monitoringWei, Yukun January 2018 (has links)
Deterministic methods have been used in geotechnical engineering for a long period, such as slope stability calculations. However, only applying deterministic methods is subjective and imperfect. There is a demand to develop a systematic methodology to link the assessed slope stability and field measurement data, which is also known as inverse analysis and forward calculation. Based on the Nya Slussen project, this thesis includes the development of a methodology, deterministic calculation for 4 cross sections using finite element program Plaxis 2D and probabilistic calculation for one section. Deterministic analyses showed satisfying results for all the studied cross sections since their factors of safety exceeded the minimum requirement. In probabilistic design, three parameters were found to have the most uncertainties through sensitivity analysis (undrained shear strength of clay, Young’s modulus of clay and friction angle of fill). Inverse analysis was done by testing different values of them in Plaxis and to try to match the displacement components provided by field measurement. After finding the best optimization for all the parameters, forward calculation gave a final factor of safety. It is suggested that both of the methods should be utilized together for better assessment.
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Probabilistic Fault Displacement Hazard Analysis for Reverse Faults and Surface Rupture Scale InvarianceRoss, Zachary E 01 March 2011 (has links) (PDF)
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A methodology is presented for evaluating the potential surface fault displacement on reverse faults in a probabilistic manner. This methodology follows the procedures put forth for Probabilistic Fault Displacement Hazard Analysis (PFDHA). Empirical probability distributions that are central to performing a PFDHA are derived from field investigations of reverse faulting events. Statistical analyses are used to test previously assumed properties of scale invariance with respect to magnitude for normalized displacement. It is found that normalized displacement is statistically invariant with respect to magnitude and focal mechanism, allowing for the combination of a large number of events into a single dataset for regression purposes. An empirical relationship is developed using this single dataset to be used as a fault displacement prediction equation. A PFDHA is conducted on the Los Osos fault zone in central California and a hazard curve for fault displacement is produced. A full sensitivity analysis is done using this fault as a reference, to test for the sources of variability in the PFDHA methodology. The influence of the major primary variables is quantified to provide a future direction for PFDHA.
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Silent Refuge? A Critical Democratic Exploration of Voice and Authorship among Resettled Iraqis in the United StatesKeyel, Jared Andrew 08 August 2019 (has links)
The 2003 United States (U.S.)-led invasion and occupation of Iraq caused hundreds of thousands of deaths and led to the displacement of millions of individuals in that country. Between March 20, 2003 and late 2017, more than 172,000 Iraqis left their country as refugees and resettled in the United States. This dissertation focuses on a small cohort of that population who resettled in various locations in the U.S. after 2003. This research contributes an empirical and theoretical exploration of the possibilities for political agency for resettled Iraqis in the United States. Grounded in literature suggesting those displaced commonly experience constrained agency framed as "silence/ing" and/or "voicelessness," I identify three requirements to democratic participation: sufficient time to exercise voice, adequate information and attenuating lingering suspicion of (authoritarian) government. Moreover, despite constraints, opportunities for engagement existed including discussion and dialogue; civil society volunteering; and activism. Drawing on 15 semi-structured qualitative interviews, this work first critically explores the American invasion of Iraq and the social and political breakdown that it triggered in that country. I argue that the conflict was an aggressive war and that, consequently, the United States should be held responsible for all of the harm it has caused to the people of Iraq. I describe the violence committed by the American military and I trace the connections between the erosion of interviewees' personal safety and their decisions to leave Iraq and resettle in the U.S. I contend that their various personal decisions to seek refuge were important agentic acts. I then delve into participants' post-resettlement opportunities for belonging in American society and analyze several ways that negative media and government discourses and policies concerning refugees, Arabs, and Muslims contributed to experiences of constraint, unease and precarity. I explore the importance of finding opportunities to engage in personal and cultural exchange with friends, neighbors and colleagues. Thereafter, I examine participants' experiences and understandings of democratic membership. Elaborating several critiques of American political institutions shared by the interviewees, I consider three requirements they identified to democratic participation: sufficient time, sufficient information to make informed decisions and the lingering effects of having lived under an authoritarian government in Iraq. Subsequently, I explore the multiple sites and modes of engagement and participation shared by participants, including dialogue, debate and discussion about the decisions that affect their lives as well as volunteering with community and nonprofit organizations focused on various types of activities, and activism in response to the Trump 2017 Travel Ban. I argue that broad social mobilization and public invocation of norms of welcoming and diversity by native-born Americans can be powerful tools to enlarge spaces for democratic agency for refugees otherwise targeted by discriminatory government actions. I then return to the question of "silence" in refuge that prompted this study and the importance of deliberate, daily interactions and exchange among newcomers and native-born Americans to expand spaces for resettled refugees to engage in American society. Thereafter, I examine the salience of local organizations and activities as sites of engagement and venues for expressions of agency for those I interviewed. I then outline possible directions for future research investigating the role(s) of refugee-led organizations in resettlement and community building. I close by describing the implications this work has for policy and activism. / Doctor of Philosophy / The 2003 United States (U.S.)-led invasion and occupation of Iraq caused hundreds of thousands of deaths and led to the displacement of millions of individuals in that country. Between March 20, 2003 and late 2017 more than 172,000 Iraqis left their country as refugees and resettled in the United States. This dissertation focuses on a small cohort of that population who resettled in various locations in the U.S. after 2003. This research contributes an exploration of the possibilities for political agency for resettled Iraqis in the United States. Grounded in literature suggesting those displaced commonly experience constrained agency framed as “silence/ing” and/or “voicelessness,” I identify three requirements to democratic participation: sufficient time, adequate information and attenuating lingering suspicion of (authoritarian) government. Moreover, despite constraints, opportunities for engagement existed including discussion and dialogue; civil society volunteering; and activism. Drawing on 15 qualitative interviews, this work first explores the American invasion of Iraq and the social and political breakdown in that country that it triggered. I argue that the conflict was an aggressive war and that, consequently, the United States should be held responsible for all of the harm it has caused to the people of Iraq. I describe the violence committed by the American military and I trace the connections between the erosion of interviewees’ personal safety and their decisions to leave Iraq and resettle in the U.S. I then delve into participants’ post-resettlement opportunities for belonging in American society and analyze several ways that negative media portrayals and government policies concerning refugees, Arabs, and Muslims shaped those resettled individuals’ life experiences. I explore the importance for interviewees of finding opportunities to engage in personal and cultural exchange with their friends, neighbors and colleagues. Thereafter, I examine participants’ experiences and understandings of democratic membership. I then consider three requirements interviewees identified to democratic participation: sufficient time, adequate information to make informed decisions and the lingering effects of having lived under an authoritarian government in Iraq. Subsequently, I describe the multiple sites and modes of engagement and participation shared by interviewees including dialogue, debate and discussion about the decisions that affect their lives, volunteering with community and nonprofit organizations and activism in response to the Trump 2017 Travel Ban. I argue that broad social mobilization and public invocation of norms of welcoming and diversity by native-born Americans can be powerful tools to enlarge participatory spaces for refugees. I then return to the question of silent refuge that prompted this study and the importance of deliberate, daily interactions and exchange among newcomers and native-born Americans to expand spaces for resettled refugees to engage in American society. Thereafter, I examine the importance of local organizations and activities for participants. I then outline possible directions for future research investigating the role(s) of refugee-led organizations in resettlement and community building. I close by describing the implications this work has for policy and activism.
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LANDLORDS, TENANTS, AND THE INFORMALITY OF THE PRIVATE PROVISION OF LOW-COST RENTAL UNITS: A CASE STUDY OF HAMILTON, ONTARIO / THE PRIVATE PROVISION OF LOW-COST RENTAL UNITS: A CASE STUDYKinsella, Kathleen January 2022 (has links)
Housing affordability is an enduring issue globally. Disproportionately affected by this trend are renters: those households who do not own their primary dwelling. Rather than being a transitionary phase – a stepping stone to homeownership – as in decades past; renting is becoming a permanent, and often financially draining, state for many households. Housing affordability is significant to the lives of renters, as renters overwhelmingly spend more of their income, as a proportion, on housing than homeowners do. In Canada, renters are not eligible for many wealth subsidies that homeowners enjoy (i.e., the exclusion of capital gains tax on the sale of primary residence), have less autonomy over their living space, and less security of tenure. These concerns, combined with aging multi-unit rental stock, disinvestment of governments from social housing funding, and a funneling of private funds towards condominium developments, has left those in the rental market with increasingly fewer housing options. This dissertation seeks to explore how households renting in the low-cost segment of the housing market gain access to housing and why they move. Special emphasis is placed on the nom-purpose built market, and a tool for better enumerating otherwise undocumented housing units is proposed. Findings suggest that previously undocumented, secondary units play a significant role in local housing markets, particularly within dense 19th century neighbourhoods with good access to amenities and transit. The dissertation also suggests that the social milieu of participants’ lives, including relationships with landlords and property managers, highly influences decisions to move. Lastly, the research finds that informal agreements, as well as units, characterizes entry and habitation of many units within the low-cost segment of the housing market. This dissertation contributes to the field of knowledge on residential mobility and housing geographies by exploring two primarily unexamined areas of local housing markets: informal units and informal agreements. / Thesis / Candidate in Philosophy / This dissertation examines the role of the private sector in housing individuals living in the low-cost segment of the rental market. Emphasis is placed on non-purpose built rentals and how they contribute to the larger function of local housing provision. Hamilton, Ontario is used as a case-study in all three papers that comprise the thesis. Findings are largely derived from a novel field enumeration technique and qualitative interviews with tenants. Taken together, results from the three papers indicate that the non-purpose built market plays a non-negligible role in providing affordable housing options to tenant households. The presented findings also suggest that amateur landlords and informal rental arrangements highly influence the form and function of low-cost rental units. Lastly, the papers suggest that highly mobile tenant populations are considerably affected by social milieu in the selection of housing units and intra-urban mobility decisions.
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Seismic Displacement Demands on Self-Centering Single-Degree-of-Freedom SystemsZhang, Changxuan 11 1900 (has links)
M.A.Sc. Thesis / Most conventional seismic design intends for key structural members to yield in order to limit seismic forces, leading to structural damage after a major earthquake. To minimize this structural damage, self-centering systems are being developed. But how to estimate the peak seismic displacement of a self-centering system remains a problem for practical design. This thesis addresses this need by presenting a parametric study on the seismic displacement demands of single-degree-of-freedom (SDOF) systems with flag-shaped hysteresis considering 13,440,000 nonlinear time history analyses. Ground motion records that represent seismic hazards in active seismic regions with stiff soil and rock site conditions are used. The influences of the four independent parameters that define a flag-shaped hysteresis are presented in terms of median displacement ratios, facilitating the design-level estimation of nonlinear displacement demands on self-centering systems from the spectra displacements of elastic systems. The influence of initial period on self-centering systems is similar to its influence on traditional systems with elastoplastic hysteresis, but a much lower linear limit can be adopted for self-centering systems while achieving acceptable peak displacements. Supplemental energy dissipation suppresses the peak displacement but additional energy dissipation becomes less effective as more is added. The effect of nonlinear stiffness is small as long as it is positive and close to zero, but a negative nonlinear stiffness can lead to unstable response. Self-centering systems located on rock sites usually have smaller displacement demands than those on stiff soil sites. When the damping ratio is increased or decreased, the displacement ratios do not necessarily decrease or increase consistently. A tangent stiffness proportional damping model is considered, leading to a significant increase in displacement demands but similar overall trends. Based on the observations, regression analysis is used to develop a simplified equation that approximates the median inelastic displacement ratios of self-centering systems for design. / Thesis / Master of Applied Science (MASc)
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The Spatial Theory of Linear Elastic Members by Direct Kinematic MethodSinha, Mithilesh Kumar 02 1900 (has links)
<p> In this work the direct, kinematic, small-displacement theory has been developed for the analysis of thin, elastic members which are curved and twisted in their natural configurations. Principles of continuum mechanics have been used to derive the equations of equilibrium. Throughout this investigation the three-dimensional aspect of the problem is preserved. Local kinematic compatibility of the displacement field has been investigated by the formal Saint-Venant's method. This development serves to substantiate the validity of the kinematic tridimensional approach. By the judicious neglection of small terms of higher order throughout this analysis, the basic system of equations arrived at by the author admit favourable comparison with the existing equations by other authors.</p> / Thesis / Master of Engineering (MEngr)
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