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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Perfil da atividade de ectonucleotidases em plaquetas e agregação plaquetária em pacientes com lúpus eritematosos sistêmico / Profilet of the ectonucleotidase activity and platelets agreggation in systemic erythematosus lupus patients

Rosa, Cíntia Saydelles da 28 May 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Systemic Lupus Erythematosus (SLE) is a chronic inflammatory disease that affects mostly women in reproductive age and sometimes cause permanent damage. The development of cardiovascular disease, especially atherosclerosis, is the leading cause of death in SLE. However, its etiology and relationship with the development of atherosclerosis remain unknown. Several studies have shown that platelets have relevant properties to thrombogenesis, such as the release of ADP, a molecule capable of inducing platelet aggregation. Adenosine, derived from the hydrolysis of ATP and ADP, in turn has antiagreggant properties. The control of extracellular levels theses molecules and subsequent purinergic signaling induced by them is carried out by enzymes NTPDase, E-NPP, 5'-nucleotidase and ADA. Therefore, the objective of this study was to evaluate the activity of these ectonucleotidases in platelets and platelet aggregation profile in patients with LES. An increase in the activity of the enzymes NTPDase, E-NPP, 5'-nucleotidase and ADA was observed in platelets of patients with lupus compared with control subjects. No difference on platelet aggregation of patients with lupus was observed when compared to control. The increase in activity of E-NTPDase, E-NPP and 5'-nucleotidase seems to be a compensatory organic response against the pathological condition, to generate higher concentration of adenosine. But the ADA activity also is increased in platelets of patients with SLE and may decrease the concentration of adenosine, which favors prothrombotics process. Thus, the results suggest that the ectoenzymes may be involved in the modulation of atherosclerotic processes that occur in SLE. / O lúpus Eritematoso Sistêmico é uma doença crônica, inflamatória e sistêmica, que afeta principalmente mulheres em idade reprodutiva e desencadeia danos permanentes na maioria dos casos. O desenvolvimento de doenças cardiovasculares, especialmente aterosclerose, é a principal causa de morte em pacientes lúpicos. Entretanto sua etiologia e relação com o desenvolvimento de aterosclerose permanecem desconhecidos. Vários estudos demonstraram que as plaquetas apresentam propriedades relevantes na trombogênese, como a liberação de ADP, uma molécula capaz de induzir a agregação plaquetária. A adenosina, proveniente da hidrólise do ATP e ADP, por sua vez apresenta propriedades antiagregantes. O controle dos níveis extracelulares destas moléculas e a consequente sinalização purinérgica por elas induzidas é realizado pelas enzimas NTPDase, E-NPP, 5'-nucleotidase e ADA. Sendo assim, o objetivo deste trabalho foi avaliar a atividade destas ectonucleotidases em plaquetas bem como o perfil da agregação plaquetária em pacientes lúpicos. Um aumento na atividade das enzimas NTPDase, E-NPP, 5'-nucleotidase e ADA foi observado em plaquetas de pacientes com LES, quando comparado com sujeitos controles. Nenhuma diferença no perfil de agregação plaquetária de pacientes lúpicas foi observada, quando comparado ao controle. O aumento na atividade da NTPDase, da E-NPP e da 5'-nucleotidase parece ser uma resposta compensatória orgânica frente ao estado patológico para gerar maior concentração de adenosina. Porém a atividade da ADA também encontra-se aumentada em plaquetas de pacientes com diagnóstico de LES, podendo diminuir a concentração de adenosina, o que favorece estágios prótrombóticos. Desse modo, os resultados encontrados sugerem que as ectoenzimas podem estar envolvidas na modulação dos processos ateroscleróticos que ocorrem no LES.
32

The Nernst-Planck-Poisson Reactive Transport Model for Concrete Carbonation and Chloride Diffusion in Carbonated and Non-carbonated Concrete

Alsheet, Feras January 2020 (has links)
The intrusion of chlorides and carbon dioxide into a reinforced concrete (RC) structure can initiate corrosion of the reinforcing steel, which, due to its expansive nature, can damage the structure and adversely affects its serviceability and safety. Corrosion will initiate if at the steel surface the concrete free chloride concentration exceeds a defined limit, or its pH falls below a critical level. Hence, determination of the time to reaching these critical limits is key to the assessment of RC structures durability and service life. Due to the ionic nature of the chlorides and the bicarbonate anion (HCO3-) formed by the CO2 in the multi-ionic pore solution, the transport of both species is driven by Fickian diffusion combined with electromigration and ionic activity, which can be mathematically expressed by the Nernst-Planck-Poisson (NPP) equations. For a complete representation of the phenomenon, however, the NPP equations must be supplemented by the relevant chemical equilibrium equations to ensure chemical balance among the various species within the concrete pore solution. The combination of NPP with the chemical equilibrium equations is often termed the NPP reactive transport model. In this study, such a model is developed, coded into the MATLAB platform, validated by available experimental data, and applied to analyze the time-dependent concrete carbonation and the movement of chlorides in carbonated and non-carbonated concrete. The results of these analyses can be used to predict the time to corrosion initiation. The transient one-dimensional governing equations of NPP are numerically solved using the Galerkin’s finite element formulation in space and the backward (implicit) Euler scheme in the time domain. The associated system of chemical equilibrium equations accounts for the key homogeneous and heterogeneous chemical reactions that take place in the concrete during carbonation and chlorides transport. At each stage of the analysis, the effects of these reactions on the changes in the pore solution chemical composition, pH, cement chloride binding capacity, concrete porosity, and the hydrated cement solids volumetric ratio are determined. The study demonstrates that given accurate input data, the presently developed NPP reactive transport model can accurately simulate the complex transport processes of chlorides and CO2 in concrete as a reactive porous medium, and the ensuing physical and chemical changes that occur due to the reaction of these species with the pore solution and the other cement hydration products. This conclusion is supported by the good agreement between results of the current analyses with the corresponding available experimental data from physical tests involving carbonation, and chloride diffusion in non-carbonated and carbonated concrete. / Thesis / Doctor of Philosophy (PhD)
33

Modeling and Assessment of Emergency Mitigation Preparedness & Vulnerability for External Events in Nuclear Power Plants / Assi _ Ahmad _ Final Submission 2014 _ M.A.Sc.

Assi, Ahmad 11 1900 (has links)
Thesis Abstract Current Nuclear Power Plant (NPP) design does not account for Beyond Design Basis Events (BDBEs) and thus lack the provisions to effectively mitigates complete loss of AC power and total loss of heat sink. Furthermore, parametric models used in PRA studies to assess Nuclear Power Plant’s safety risk for BDBE and External Events (EE) have significant limitations and proved ineffective to provide solutions on how to mitigate in BDBE or EEs situations. The Fukushima accident is a good example where PRA assessments did not provide the necessary means to cool or contain the reactors effectively. In this thesis, Emergency Mitigation Preparedness (EMP) model and assessment is proposed. The EMP model is objective and practical in evaluating NPP’s mitigation readiness in BDBE and EEs situations and provide a practical NPP Vulnerability indicator gauge which can potentially be used in risk-informed decisions. This will aid further in the NPP to improve in areas of emergency planning, enhance site and reactor design and improve workers safety and readiness to execute effective mitigation procedures and emergency plans. / Thesis / Master of Engineering (ME)
34

Experimental and Analytical strategies to assess the seismic performance of auxiliary power systems in critical infrastructure

Ghith, Ahmed January 2020 (has links)
The performance of nonstructural components in critical infrastructure, such as nuclear power plants (NPPs), has been primarily based on experience and historical data. This topic has been attracting increased interest from researchers following the Fukushima Daiichi nuclear disaster in 2011. This disaster demonstrated the importance of using batteries in NPPs as an auxiliary power system, where such systems can provide the necessary power to mitigate the risk of serious accidents. However, little research has been conducted on such nonstructural components to evaluate their performance following the post- Fukushima safety requirements, recommended by several nuclear regulators worldwide [e.g., Nuclear Regulatory Commission (NRC), and Nuclear Safety Commission (NSC)]. To address this research gap, this dissertation investigates the lateral performance of an auxiliary battery power system (ABPS) similar to those currently existing/operational in NPPs in Canada. The ABPS was experimentally tested under displacement-controlled quasi-static cyclic fully-reversed loading that simulates lateral seismic demands. Due to the presence of sliding batteries, the ABPS was then tested dynamically under increased ground motion levels on a shake table. The experimental results demonstrated that the design guidelines and fragility curves currently assigned to battery rack systems in the FEMA P58 prestandards do not encompass all possible failure mechanisms. A 3D numerical model was also developed using OpenSees software. The model was validated using the experimental results. The model results showed that the lateral performance of ABPS with different configurations (i.e. different lengths, tiers, and seismic categories) is influenced by the capacity of the L-shaped connection between the side rails and the end rail. However, the model was not able to predict all the damage states from the dynamic experimental tests, since the rocking/sliding/impact behavior of the batteries is a highly complex nonlinear problem by nature and beyond the scope of this study. The model presented is limited to the assessment of the lateral performance of different ABPS statically. This dissertation demonstrated the difference between the observed behavior of laboratory-controlled lateral performance tests of ABPSs operational/existing in NPPs and the behavior of ABPSs found in the literature that relied on limited historical and experience data. Finally, this dissertation laid the foundations for the need to further investigate the behavior of other safety-related components in NPPs and assess their compliance with new post-Fukushima design requirements. / Thesis / Doctor of Philosophy (PhD)
35

Elevation Effects on Key Processes of Carbon Cycling in South Ecuadorian Mountain Forests / Der Einfluss der Meereshöhe auf Schlüsselprozesse des Kohlenstoffkreislaufs in Südecuadorianischen Bergregenwäldern

Moser, Gerald 24 January 2008 (has links)
No description available.
36

Nitrogen Uptake by Vegetation in the Wakkerstroom Wetland, South Africa

Dufbäck, Emma January 2019 (has links)
The lack of proper wastewater treatment inhibits the social and economic development in many communities. The South African town Wakkerstroom is an example where wastewater is first treated before it is released. Due to the lack of technical expertise and funding to manage the sewage disposal system, a large part of the wastewater goes directly, without any treatment, into a stream feeding the Wakkerstroom wetland. The wetland purifies the wastewater and provides clean water downstream, thus is indispensable for its detoxification capacity. One relatively cheap method to determine the absorption capacity of a wetland with respect to nitrogen loading is to investigate the nitrogen uptake by the wetland vegetation. In this study, the nitrogen uptake of the vegetation in the Wakkerstroom wetland during the growing seasons between the years 2000-2018 was investigated by using harvested biomass and its nitrogen content as a proxy. The interannual variability of Net Primary Production (NPP) was calculated using a Light Use Efficiency (LUE) model for the period 2000-2018. The NPP derived with LUE-modelling was compared to NPP based on an end-of season harvest of biomass in March 2019. The nitrogen content and carbon and nitrogen (C:N) ratio were determined in the harvested biomass by carbon and nitrogen content analysis. The annual nitrogen uptake of the growing seasons between the years 2000-2018 was subsequently determined by multiplying the calculated NPP by the fraction of nitrogen found in the harvested material. The NPPtot based on harvested biomass (NPPharvest) towards the end of the growing season 2018/2019 was estimated to be 2.01 kg‧m-2‧season-1. The NPPtot calculated from LUE modelling (NPPLUE) varied between 0.49-1.64 kg‧m-2 for the growing seasons between 2000-2018. NPPharvest was between 1.2-4 times higher compared to NPPLUE, probably due to overestimation of NPPharvest because of biomass sampling of more than one-year production, or underestimation of NPPLUE due to a low maximum radiation conversion efficiency factor, εmax. The community mean nitrogen (N) content found in the biomass harvested aboveground was 1.29 % for the Phragmites community and 1.00 % for the Typha community. The nitrogen uptake of the vegetation was estimated to vary between 6.10-20.5 g N∙m-2 per growing season between the years 2000-2018. / Bristen på adekvata reningstekniker för att behandla avloppsvatten hämmar den sociala och ekonomiska utvecklingen i många samhällen. Den sydafrikanska staden Wakkerstroom är ett exempel där avloppsvatten först renas innan det släpps ut. På grund av brisen på teknisk kompetens och finansiering att hantera reningsverket som avlägsnar avloppsvatten så läcker en stor del av det orenade avloppsvattnet ut i en våtmark i Wakkerstroom via en närliggande å. Våtmarken är av regional betydelse för sin reningskapacitet då den renar avloppsvattnet och förser användare nedströms med rent vatten. En viktig aspekt för att bestämma en våtmarks reningskapacitet med avseende på kväve (N) är att undersöka växternas kväveupptag i våtmarken. Kväveupptaget hos växterna i våtmarken i Wakkerstroom under växtsäsongerna mellan år 2000–2018 undersöktes genom att använda skördad biomassa och dess kväveinnehåll som proxy. Den årliga variabiliteten hos nettoprimärproduktionen (NPP) beräknades genom att använda en LUE (Light Use Efficiency)-modell för perioden 2000-2018. NPP framtaget med LUE-modellering jämfördes med NPP baserat på biomassa skördad i slutet av växtsäsongen i mars 2019. Kväveinnehållet och kol-kväve (C:N) kvoten bestämdes hos den skördade biomassan genom en kol- och kväveanalys. Det årliga kväveupptaget under växtsäsongerna mellan 2000–2018 togs därefter fram genom att multiplicera beräknad NPP med kvävefraktionen erhållen från den skördade biomassan. NPPtot framtaget med biomassa skördad i slutet av växtsäsongen 2018/2019 (NPPbiomassa) uppskattades vara 2,01 kg‧m-2‧säsong-1. NPPtot beräknat med LUE-modellering (NPPLUE) varierade mellan 0,49–1,64 kg‧m-2 under växtsäsongerna mellan år 2000–2018. NPPbiomassa var 1,2–4 gånger högre i jämförelse med NPPLUE, vilket troligtvis berodde på att NPPbiomassa överskattades på grund av att mer än en årsproduktion av biomassa skördades, eller för att NPPLUE underskattades på grund av ett för lågt värde på den maximala effektivitetsfaktorn εmax valdes. Medelvärdet för kväveinnehållet erhållen i biomassan skördad ovanför vattennivån var 1,29 % för Phragmites-samhället och 1,00 % för Typha-samhället. Kväveupptaget hos växterna varierade mellan 6,10–20,5 g N∙m-2 per växtsäsong mellan år 2000–2018.
37

應用Landsat影像於都市碳吸存效益之分析 / Application of Landsat Image in Urban Carbon Sequestration Analysis

蔡榮恩, Tsai, Jung En Unknown Date (has links)
自工業革命後,隨著科技的進步,人口、經濟、醫療技術皆快速發展,也因人類需求的增加而大量燃燒化石燃料,大規模的砍伐熱帶雨林,導致大氣中二氧化碳大量增加,進而衍生溫室效應的發生,甚至造成全球氣候變遷。 在全球暖化的狀態下,聯合國氣候變化綱要公約與京都議定書中都明確肯定森林可固定主要溫室氣體二氧化碳,由於森林具備吸收和儲存二氧化碳的能力,其對於生態系統中的碳循環功能扮演重要的角色。若能有效監控森林資源,便能管理溫室氣體,且能提出有效的控管方式。 而本研究將應用遙測技術於碳吸存與環境變化的監測,透過美國大地衛星影像(Landsat)進行不同時期與區域之碳吸存的評估,與以往研究之最大差異為可進行大尺度與多時期的碳吸存評估,並且達到經濟、準確、有效提升效率之目標。 本研究根據光能利用率(Light use efficiency)為基礎模型,計算2005-2010之植生淨初級生產量(Net Primary Productivity, NPP),且配合不同的研究區域:台北、高雄,進一步探討不同的氣候條件與土地利用的條件下,其差異性對於NPP之影響。 成果顯示,在不同環境條件下碳吸存能力受到氣候條件影響最大,且在資料具有缺漏狀態下,依然能反映不同區域之趨勢,雖無法有效評估年總量,但仍可供評估區域性碳吸存能力之趨勢。 / Since the industrial revolution, with the rapid progress of science and technology, population, economy, and medical technology also grow rapidly. Because of increased human demand, coupled with burning lots of fossil fuels, and large-scale felling of tropical rain forests, which result in a significant increase in atmospheric carbon dioxide, and then trigger the greenhouse effect to occur, hence causing global climate change. Under the global warming condition, the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol (KC) both clearly affirmed that forests can fix the main greenhouse gas—carbon dioxide. Because forests have the ability to absorb and store carbon dioxide, they plan an important role in carbon cycle function for ecosystem. If we can effectively monitor forest resources, we will be able to manage greenhouse gases, and can come up with effective control methods. In the present study, we will use remote sensing technology to monitor carbon sequestration and environmental changes. Using Landsat images, we assessed carbon sequestration of different time periods and areas. The biggest difference between this study and previous researches is that large-scale and multi-temporal carbon sequestration assessment can be done, and the goals of economic, accurate, and increasing efficiency can be achieved. In this study, the Net Primary Productivity (NPP) of 2005-2010 was calculated based on the light use efficiency model. By comparing the results of different research areas—Taipei and Kaohsiung, the effects of different climatic conditions and land use conditions on NPP was investigated. The results show that, under different environmental conditions, the carbon sequestration capacity is affected the most by climatic conditions. Furthermore, in the absence of data, it still can reflect the trend of different regions. Although not being able to effectively assess the total amount of a year, it still can be used to assess the trend of regional carbon sequestration capacity.
38

Late Quaternary Vegetation History And Climate Change In The Gobi Desert, South Mongolia / Spätquartäre Vegetationsgeschichte und Klimaveränderungen in der Wüste Gobi, südliche Mongolei

Murad, Waheed 28 June 2011 (has links)
No description available.
39

Aplicação da manutenção centrada em confiabilidade (RCM) na otimização do programa de manutenção de centrais termonucleares / Application of reliability-centred mainteinance in optimization of the nuclear power plants preventive maintenance program

Quintella, Luciano Confort [UNESP] 04 July 2016 (has links)
Submitted by LUCIANO CONFORT QUINTELLA null (l_quintella@yahoo.com.br) on 2016-08-16T18:29:05Z No. of bitstreams: 1 UNESP-FEG - Dissertação de Mestrado - APLICAÇÃO DA MANUTENÇÃO CENTRADA EM CONFIABILIDADE NA OTIMIZAÇÃO DO PROGRAMA DE MANUTENÇÃO DE CENTRAIS TERMONUCLEARES - Luciano C Quintella_Rev167 - REVISÃO FINAL.pdf: 5630978 bytes, checksum: 6d3c05b844c7ac7c30dd808f1c82303b (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: O arquivo submetido não contém o certificado de aprovação assinado. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija esta informação e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2016-08-17T14:39:55Z (GMT) / Submitted by LUCIANO CONFORT QUINTELLA null (l_quintella@yahoo.com.br) on 2016-09-07T00:13:03Z No. of bitstreams: 1 UNESP-FEG - Dissertação de Mestrado - APLICAÇÃO DA MANUTENÇÃO CENTRADA EM CONFIABILIDADE NA OTIMIZAÇÃO DO PROGRAMA DE MANUTENÇÃO DE CENTRAIS TERMONUCLEARES - Luciano C Quintella_Rev168 - REVISÃO FINAL.pdf: 4453734 bytes, checksum: b3c4369bb61bf3c735292c7280dfc961 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-12T16:47:20Z (GMT) No. of bitstreams: 1 quintella_lc_me_bauru.pdf: 4453734 bytes, checksum: b3c4369bb61bf3c735292c7280dfc961 (MD5) / Made available in DSpace on 2016-09-12T16:47:20Z (GMT). No. of bitstreams: 1 quintella_lc_me_bauru.pdf: 4453734 bytes, checksum: b3c4369bb61bf3c735292c7280dfc961 (MD5) Previous issue date: 2016-07-04 / A função manutenção vem sendo considerada como fator estratégico para as empresas, pois através do alinhamento de suas políticas corporativas e integração de seus programas de gestão de ativos, de riscos e de ciclo de vida de suas unidades de negócios, as empresas vêm buscando a constante redução de custos e a melhoria de seus resultados operacionais. E, assim, obtendo maior competitividade. A Manutenção Centrada em Confiabilidade (RCM) é um método já bem disseminado por todo o mundo e que, ao longo dos anos, vem promovendo estes diferenciais estratégicos através de preceitos que possibilitam a elaboração de Programas de Manutenção Preventiva de custo-eficaz, através de um método para a definição de políticas de manutenção mais adequadas, com o foco na manutenção da função dos ativos em seu contexto operacional. Ao longo dos anos, o método RCM vem sendo aplicado em inúmeros estudos de casos em diferentes empresas de diversos seguimentos, onde podem ser observadas novas adaptações ou simplificações do método RCM clássico. Estas adaptações buscam uma maior adequação as particularidades destas empresas e/ou um retorno mais rápido de resultados. O setor nuclear de geração de energia foi um dos pioneiros na adoção e disseminação do RCM, e vem desenvolvendo processos simplificados de aplicação do RCM, como o “Streamlinned RCM” e o “método PMO” (Otimização do Programa de Manutenção, do inglês: Preventive Maintenance Optimization). Estes estudos mostram que o método PMO apresenta uma maior flexibilidade, o que permite a adoção de diferentes estratégias de aplicação que, por sua vez, têm trazido resultados expressivos para as empresas, através da otimização dos Programas de Manutenção já existentes. Com base na literatura, neste trabalho são abordadas questões referentes ao RCM e sua contextualização na área nuclear, estudos sobre os métodos simplificados do RCM e o desenvolvimento do método PMO. Por fim, é realizada uma aplicação prática do método PMO sobre os sistemas relacionados e subsistemas do Sistema de Remoção de Calor Residual (JN), mais especificamente, sobre as Bombas de injeção de segurança do Sistema de Injeção de Alta Pressão (JND) da Usina Nuclear Angra 2. Através dos resultados obtidos com esta aplicação, pretende-se otimizar o Programa de Manutenção da Planta (PMP) referente a estes equipamentos e, assim, validar o método PMO como ferramenta para a melhoria contínua do Programa de Gestão de Ativos e Ciclo de Vida da Usina Nuclear Angra 2. / Corporations tend to consider maintenance work a strategic element. It is through maintenance—especially the alignment between corporate policies and integration of their programs to manage assets, risks, and life cycles of business units—that corporations try to continuously improve their results, reduce their operational costs, and, therefore, increase their competitiveness. Reliability Centered Maintenance (RCM) is a popular method across the world; it has been promoting competitiveness through concepts that allow the design of cost-effective Preventive Maintenance Programs These programs are effective because they entail appropriate maintenance policies that are focused on the preservation of the assets functions in their operational context and on the formation of technical knowledge basis supported by hard data. Throughout the years, RCM has been applied in numerous case studies and in different companies engaged in a variety of market segments. Such diversity in the application of RCM allowed us to observe new adaptations and variations of the classic method. Such adaptations aim to better respond to specific operational contexts in and within production units, as well as achieve faster results. The nuclear power sector has pioneered regarding the adoption and dissemination of RCM; it has been developing simplified versions of RCM, such as the “Streamlined RCM” and the PMO (Preventive Maintenance Optimization). These studies demonstrate that the PMO presents enhanced flexibility, which allows the adoption of different strategies; such enhanced flexibility brings expressive results to corporations as pre-existing maintenance programs are optimized. Based on the currently available literature, this dissertation addresses numerous questions regarding RCM and its application to nuclear power segments. It also addresses studies about simplified versions of RCM and the development of the PMO method. The discussion is supplemented with a practical application of the PMO method regarding auxiliary systems and sub-systems of Removal of Residual Heat System (JN), especially those regarding the security injection pumps of the High Pressure Injection System (JND) at Angra II Nuclear Plant. Through the results obtained from this application, it is possible to optimize the Maintenance Program of these equipments, and therefore, validate the PMO method as a tool of continuous improvement of the Assets and Life Cycle Program of Angra II.
40

Environmental Justice Issues in Communities Hosting US Nuclear Power Plants

January 2014 (has links)
abstract: This study explores the potential risks associated with the 65 U.S.-based commercial nuclear power plants (NPPs) and the distribution of those risks among the populations of both their respective host communities and of the communities located in outlying areas. First, I examine the relevant environmental justice issues. I start by examining the racial/ethnic composition of the host community populations, as well as the disparities in socio-economic status that exist, if any, between the host communities and communities located in outlying areas. Second, I estimate the statistical associations that exist, if any, between a population's distance from a NPP and several independent variables. I conduct multivariate ordinary least square (OLS) regression analyses and spatial autocorrelation regression (SAR) analyses at the national, regional and individual-NPP levels. Third, I construct a NPP potential risk index (NPP PRI) that defines four discrete risk categories--namely, very high risk, high risk, moderate risk, and low risk. The NPP PRI allows me then to estimate the demographic characteristics of the populations exposed to each so-defined level of risk. Fourth, using the Palo Verde NPP as the subject, I simulate a scenario in which a NPP experiences a core-damage accident. I use the RASCAL 4.3 software to simulate the path of dispersion of the resultant radioactive plume, and to investigate the statistical associations that exist, if any, between the dispersed radioactive plume and the demographic characteristics of the populations located within the plume's footprint. This study utilizes distributive justice theories to understand the distribution of the potential risks associated with NPPs, many of which are unpredictable, irreversible and inescapable. I employ an approach that takes into account multiple stakeholders in order to provide avenues for all parties to express concerns, and to ensure the relevance and actionability of any resulting policy recommendations. / Dissertation/Thesis / Ph.D. Environmental Social Science 2014

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