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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.
181

Arsenic Contamination in Groundwater in Vietnam: An Overview and Analysis of the Historical, Cultural, Economic, and Political Parameters in the Success of Various Mitigation Options

Ly, Thuy M 01 May 2012 (has links)
Although arsenic is naturally present in the environment, 99% of human exposure to arsenic is through ingestion. Throughout history, arsenic is known as “the king of poisons”; it is mutagenic, carcinogenic, and teratogenic. Even in smaller concentrations, it accumulates in the body and takes decades before any physical symptoms of arsenic poisoning shows. According to the World Health Organization (WHO), the safe concentration of arsenic in drinking water is 10 µg/L. However, this limit is often times ignored until it is decades too late and people begin showing symptoms of having been poisoned. This is the current situation for Vietnam, whose legal arsenic concentration limit is 50 µg/L, five times higher than the WHO guidelines. Groundwater in Vietnam was already naturally high in arsenic due to arsenic-rich soils releasing arsenic into groundwater. Then, in the past half century, with the use of arsenic-laden herbicides dispersed during the Vietnam War and subsequent industrial developments, the levels of bio-available arsenicals has dangerously spiked. With the proliferation of government-subsidized shallow tube-wells in the past two decades, shallow groundwater has become the primary source for drinking and irrigation water in Vietnam. This is a frightening trend, because this groundwater has arsenic concentrations up to 3050 µg/L, primarily in the +3 and +5 oxidation states, the most readily available oxidation states for bioaccumulation. This thesis argues that measures must be taken immediately to remedy the high concentration of arsenic in groundwater, which in Vietnam is the primary and, in some cases, the sole source of water for domestic consumption and agricultural production. Although there are numerous technologies available for treating arsenic in groundwater, not all of them are suited for Vietnam. By analyzing the historical, cultural, economic, and political parameters of Vietnam, several optimal treatments of groundwater for drinking water emerged as most recommended, a classification that is based on their local suitability, social acceptability, financial feasibility, and governmental support. Further research on irrigation water treatment is proposed due to the need for sustainable crop production, the safe ingestion of rice and vegetables, and the continued growth of Vietnam’s economy, which is heavily dependent on agriculture.
182

NATURAL PHENOMENA AS POTENTIAL INFLUENCE ON SOCIAL AND POLITICAL BEHAVIOR: THE EARTH’S MAGNETIC FIELD

East, Jackie R 01 January 2014 (has links)
Researchers use natural phenomena in a number of disciplines to help explain human behavioral outcomes. Research regarding the potential effects of magnetic fields on animal and human behavior indicates that fields could influence outcomes of interest to social scientists. Tests so far have been limited in scope. This work is a preliminary evaluation of whether the earth’s magnetic field influences human behavior it examines the baseline relationship exhibited between geomagnetic readings and a host of social and political outcomes. The emphasis on breadth of topical coverage in these statistical trials, rather than on depth of development for any one model, means that evidence is only suggestive – but geomagnetic readings frequently covary with social and political variables in a fashion that seems inexplicable in the absence of a causal relationship. The pattern often holds up in more-elaborate statistical models. Analysis provides compelling evidence that geomagnetic variables furnish valuable information to models. Many researchers are already aware of potential causal mechanisms that link human behavior to geomagnetic levels and this evidence provides a compelling case for continuing to develop the line of research with in-depth, focused analysis.
183

Território em mutação: a implantação de central geradora eólica em Sergipe

Costa, Vanessa Santos 15 August 2013 (has links)
The energetic sector is one of the areas that more contribute for the increase of the environment degradation, mainly concerning to burning of fossil fuel since they are extreme polluters. This way, the preoccupation with the environment made man to turn to nature searching for in its elements energetic alternatives that could be able to provide energy to sustain his social and technologic development. In this context, we focused our analyse on one of the energetic alternatives that comes from replaceable and natural resources, the eolian energy, since it is a new clear source of energy that aims at reducing these problems. In Sergipe State, with the purpose of contributing for the environment preservation and increasing the energetic matrix of our country, it has being implanted, in the county of Barra dos Coqueiros its first eolian central generator. This project brings the installation of 23 windmills and they will have the capability of producing 35, 6 MW of energy. This location was chosen due to the environment conditions, as the climate and alleviation that are favorable to the project development. Thus, this present study refers to the analyze of the first wind farm implanted in the State and it aimed at learning the general perception of the social authors involved in the process, such as the surrounding population, the government and the responsible enterprise. The methodology began by the bibliographic surveys and visitation in both public and private agencies, field work with application of questionnaires and interviews, during the period of April and July, 2012. With this study it could be observed that the arrival of this enterprise provoked changes in the location landscapes caused by the windmill installations as well as daily life changing of the surrounding people. We searched to comprehend the perception of the main three segments involved referring to eolian energy as a sustainable energy source as well as the conformation of new territories. Government agencies and the involved enterprises in the wind farm implantation translate preocupation with the observance of the legislation, but, specially, with the participation in the magnification and diversification of the energetic matrix of both the State and Country. The majority of the surrounding inhabitants and the head office residents of the county, in turn, show themselves inadvertent or ignore that it does not mean only. a landscape change, but a production of a territory that will affect the neighbor relationship, the access, the values of the real estates, ultimately, the material and symbolic basis that until now remained in their quotidian. / O setor energetico e uma das areas que mais contribui para o aumento da degradacao ambiental, principalmente no que diz respeito a queima de combustiveis fosseis por serem extremamente poluentes. Desse modo a preocupacao com o meio ambiente fez com que o homem se voltasse para a natureza buscando nos seus elementos as alternativas energeticas capazes de fornecerem energia para sustentar o seu desenvolvimento social e tecnologico. Nesse contexto, focamos nossa analise numa das alternativas energeticas que provem dos recursos naturais renovaveis, a energia eolica, pois e uma nova fonte limpa de energia que visa diminuir esses problemas. No Estado de Sergipe, com intuito de contribuir para a preservacao do meio ambiente e aumentar a matriz energetica do pais, vem sendo implantada, no municipio de Barra dos Coqueiros sua primeira central geradora eolica. Esse projeto traz a instalacao de 23 aerogeradores e tera capacidade de produzir 35,6 MW de energia. A escolha por essa localidade foi devido as condicoes ambientais, como clima e relevo que sao favoraveis para o desenvolvimento do projeto. Assim, o presente estudo refere-se a analise do primeiro parque eolico implantado no Estado e teve como objetivo geral apreender a percepcao dos atores sociais envolvidos no processo, tais como populacao de entorno, governo e empresa responsavel pelo empreendimento. A metodologia principiou pelos levantamentos bibliograficos e visita em orgaos publicos e privados, trabalho de campo com aplicacao de questionarios e entrevistas, no periodo de abril a julho de 2012. Com esse estudo pode-se observar que a chegada desse empreendimento ocasionou transformacoes na paisagem da localidade advindas pela instalacao dos aerogeradores bem como mudancas no cotidiano da populacao de entorno. Procuramos apreender a percepcao dos tres principais segmentos envolvidos no que se refere a energia eolica como fonte energetica sustentavel assim como a conformacao de novos territorios. Os orgaos de governo e as empresas envolvidas na implantacao do parque eolico traduzem preocupacoes com o cumprimento da legislacao, mas, sobretudo, com a participacao na ampliacao e diversificacao da matriz energetica do Estado e do pais. Ja os moradores dos arredores e da sede do municipio, em sua maioria, apresentam-se alheios ou ignoram que nao se trata de apenas. uma transformacao da paisagem, mas da producao de um territorio que afetara as relacoes de vizinhanca, o acesso, o valor dos imoveis, enfim, a base material e simbolica que ate entao prevalecia em seus cotidianos.
184

Bolivia's Coca Headache: The Agroyungas Program, Inflation, Campesinos, Coca and Capitalism In Bolivia

Roberts, John D 01 January 2010 (has links) (PDF)
Bolivia in the 1980s was wracked by monetary inflation approaching levels of the German Weimar Republic. Immediately following this time of great financial crisis in Bolivia, the U.N. founded a project through the U.N.D.P. to encourage peasant farmers in Bolivia to switch from growing coca (the plant used manufacture cocaine) to growing other cash crops for market. This crop substitution and development program, called the Agroyungas Project, lasted from 1985 to 1991 and is the focus of this study. While many U.N. pundits and journalists considered the program’s initial small successes promising, it has been considered since its conclusion to be a failure. The program was poorly conceived, poorly funded and poorly executed from the start. So one question remains: why was the Agroyungas Project a failure? Additionally, was the project simply a way to steer Bolivians away from the illicit coca/cocaine economy? While on the surface this might appear to be the case, one must probe the complex situations in Bolivia deeply to uncover the true missteps behind this U.N. program. By looking at the evidence, it is apparent that crop substitution programs like the Agroyungas Project failed for a variety of reasons. Besides poor planning and execution of project plans, the project’s developers, planners and workers simply did not understand Bolivian indigenous culture and Bolivian history. However, the project was not doomed to fail. The lack of knowledge and understanding of indigenous Bolivian realities, Bolivian geography and Bolivian history directly led to the failures of the Agroyungas Project.
185

Modeling Spatial Distributions of Tidal Marsh Blue Carbon using Morphometric Parameters from Lidar

Turek, Bonnie 05 April 2023 (has links) (PDF)
Tidal marshes serve as important “blue carbon” ecosystems that accrete large amounts of carbon with limited area. While much attention has been paid to the spatial variability of sedimentation within salt marshes, less work has been done to characterize spatial variability in marsh carbon density. Driven by tidal inundation, surface topography, and sediment supply, soil properties in marshes vary spatially with several parameters, including marsh platform elevation and proximity to the marsh edge and tidal creek network. We used lidar to extract these morphometric parameters from tidal marshes to map soil organic carbon (SOC) at the meter scale. Fixed volume soil samples were collected at four northeast U.S. tidal marshes with distinctive morphologies to aid in building our predictive models. Tidal creek networks were delineated from 1-m resolution topo-bathy lidar data using a semi-automated workflow in GIS. Sample distance to tidal creeks and flow distance to the marsh edge were then determined. Log-linear multivariate regression models were developed to predict soil organic content, bulk density, and carbon density as a function of these predictive metrics at each site and across sites. Results show that modeling salt marsh soil characteristics with morphometric inputs works best in marshes with simple, single creek morphologies. Distance from tidal creeks was the most significant model predictor. Addition of distance to the inlet and tidal range as regional metrics significantly improves cross-site modeling. Our process-based approach results in predicted total marsh carbon stocks comparable to previous studies but provides trade-offs to existing simplistic carbon mapping methods. Further, we provide motivation to continue rigorous mapping of soil carbon at fine spatial resolutions and to use these results to guide salt marsh restoration projects and aid in the development of carbon markets.
186

Comparative Analysis of Maori of Aotearoa and James Bay Cree of Eeyou Istechee Cultural Heritage Values and Political Histories of Land Tenure Systems

Schaeffer, Erin 01 January 2012 (has links) (PDF)
This thesis relies on an interdisciplinary framework to conduct an investigation of seminal national policies and planning processes in New Zealand and Quebec Province, Canada related to sovereignty, indigenous land rights, and customary land tenure systems. Theoretical frameworks for this research include a comparative analysis of European legislative systems and traditional planning frameworks in relation to indigenous governance systems and land tenure systems for the Maori (NZ) and James Bay Cree (QC). Through interviews and experiential knowledge I will document tools and techniques that these indigenous communities use to navigate complex cross-cultural policy and planning processes for their own advocacy of cultural heritage values. From the Maori perspective, cultural heritage values include the concept and principles of kaitikatanga. James Bay Cree cultural heritage values include the concept and guiding principles embedded in Eeyou Iyihtiwin. These cultural heritage values represent abstract concepts and guiding principles that are embedded in and gain meaning from local context, cultural knowledge and customary traditions. The Maori and James Bay Cree share a similar orientation to the meaning and importance of land. Together these indigenous communities view land as the foundation for collective and individual identity and cultural traditions. From this perspective and meaning of land, the Maori and James Bay Cree recognize that people are a part of a greater interconnected system that spans across physical and metaphysical spaces. In practice, native or customary land tenure systems are based on cultural heritage values that support a spirit of reciprocity with an underlying expectation that a balanced system will provide for all life. This analysis may provide a new cross-cultural framework for policy and planning processes to provide opportunities for fair negotiation of sustainable land tenure systems and natural resource management.
187

Prioritising indigenous representations of geopower : the case of Tulita, Northwest Territories, Canada

Perombelon, Brice Désiré Jude January 2018 (has links)
Recent calls from progressive, subaltern and postcolonial geopoliticians to move geopolitical scholarship away from its Western ontological bases have argued that more ethnographic studies centred on peripheral and dispossessed geographies need to be undertaken in order to integrate peripheralised agents and agencies in dominant ontologies of geopolitics. This thesis follows these calls. Through empirical data collected during a period of five months of fieldwork undertaken between October 2014 and March 2015, it investigates the ways through which an Indigenous community of the Canadian Arctic, Tulita (located in the Northwest Territories' Sahtu region) represents geopower. It suggests a semiotic reading of these representations in order to take the agency of other-than/more-than-human beings into account. In doing so, it identifies the ontological bases through which geopolitics can be indigenised. Drawing from Dene animist ontologies, it indeed introduces the notion of a place-contingent speculative geopolitics. Two overarching argumentative lines are pursued. First, this thesis contends that geopower operates through metamorphic refashionings of the material forms of, and signs associated with, space and place. Second, it infers from this that through this transformational process, geopower is able to create the conditions for alienating but also transcending experiences and meanings of place to emerge. It argues that this movement between conflictual and progressive understandings is dialectical in nature. In addition to its conceptual suggestions, this thesis makes three empirical contributions. First, it confirms that settler geopolitical narratives of sovereignty assertion in the North cannot be disentangled from capitalist and industrial political-economic processes. Second, it shows that these processes, and the geopolitical visions that subtend them, are materialised in space via the extension of the urban fabric into Indigenous lands. Third, it demonstrates that by assembling space ontologically in particular ways, geopower establishes (and entrenches) a geopolitical distinction between living/sovereign (or governmentalised) spaces and nonliving/bare spaces (or spaces of nothingness).
188

Situated Architecture in the Digital Age: Adaptation of a Textile Mill in Holyoke, Massachusetts

Brooks, Dorcas A 01 January 2011 (has links) (PDF)
The City of Holyoke, Massachusetts is one of many aging, industrial cities striving to revitalize its economy based on the promise of increased digital connectivity and clean energy resources. But how do you renovate 19th century mills to meet the demands of the information age? This architectural study explores the potential impact of sensing technologies and information networks on the definition and function of buildings in the 21st century. It explores the changes that have taken place in industrial architecture since 1850 and argues for an architecture that supports local relationships and environmental awareness. The author explores the industrial history of Holyoke, appraises emerging uses of sensing technologies and presents a thorough narrative of her site analysis and conceptual design of a digital fabrication and incubation center within an existing textile mill.

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