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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.
151

Desenvolvimento de métodos analíticos para a determinação de metais traço em vegetais da família Solanaceae por espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos.

Siqueira, Marianna Pozzatti Martins de January 2017 (has links)
Neste trabalho foram desenvolvidos quatro métodos analíticos para a determinação de cádmio, cromo, cobre, níquel e ferro em vegetais da família Solanaceae, cultivados pelos métodos convencional e orgânico de produção, obtidos em feiras e mercados da cidade de Porto Alegre, Brasil. Estes vegetais são muito consumidos devido a grande quantidade de nutrientes, no entanto, podem ser contaminados por elementos potencialmente tóxicos, por meio da exposição a poluição, uso de pesticidas, fertilizantes e água contaminada. As determinações foram conduzidas pela técnica de espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos. Para Cd, Cr e Cu foram desenvolvidos três métodos independentes. No caso da determinação de Ni e Fe foi realizada análise simultânea, empregando linhas analíticas alternativas. Temperaturas de pirólise e atomização foram otimizadas para todos os elementos analisados, visando sinais analíticos com elevada sensibilidade e livres de interferências. Os métodos otimizados foram aplicados em amostras de pimentão, batata, tomate, berinjela, pimenta e physalis. Várias amostras apresentaram concentrações superiores aos limites máximos estabelecidos por legislações específicas. Os métodos propostos envolveram mínimo preparo de amostra, reduzindo riscos de contaminação, tempo analítico e custos, além de demonstrarem-se simples, precisos, rápidos e sensíveis. / In this work, four methods have been developed for the determination of cadmium, chromium, copper, nickel and iron in vegetables of the Solanaceae family, cultivated in conventional and organic farming systems, obtained from local markets and local farms, located in the city of Porto Alegre, Brazil. These vegetables are much appreciate due to the large amount of nutrients present in it. However, vegetables can be contaminated by potentially toxic elements, through the exposure to pollution, use of pesticide, fertilizers and contaminated water. The assays were carried out using a high-resolution continuum source graphite furnace atomic absorption spectrometer and direct solid sample analysis. Cd, Cr and Cu had their methods individually developed. In the case of the determination of Ni and Fe, it was applied simultaneous analysis, employing alternative analytical lines. Pyrolysis and atomization temperatures were optimized for all target elements, aiming for analytical signals with high sensitivity and free from interferences. The optimized methods were applied in samples of bell peppers, potato, tomato, eggplant, pepper and physalis. Several samples presented concentrations above the maximum permitted by specific legislation. The proposed methods were accurate, simple, fast and sensitive; moreover, a minimum sample preparation was necessary, reducing contamination, analytical time and costs.
152

Capturing Appalachia : visualizing coal, culture, and ecology

McClanahan, Bill January 2017 (has links)
Capturing Appalachia: Visualizing Coal, Culture and Ecology, draws on extensive ethnographic, archival, and ecographic research conducted across Appalachia between 2014-2016 to develop an empirically informed sociological image of the interactions between culture, geography, and industry. Of particular interest are the ways that extractive cultures in Appalachia are constructed and communicated, and so the project includes archival work researching historical images as well as fieldwork focused on the production of images. Drawing on the traditions of cultural and ‘green’ criminologies, geography, and critical ecotheory, concluding that the cultural, political, and ecological worlds of Appalachia exist in a dialectical relationship with one another, and that at the center of each is an intense cultural relationship with the region’s historic and contemporary capture (cultural, economic, and ecological) by resource extraction. These dialectical relationships are made clear in the visuality of Appalachia, with paradigms frequently challenged by the production of countervisual narratives in productions spanning photography, literature, cinema, and media. The project constitutes the first extensive empirical application of the suggestions of an emergent green-cultural criminology. This research contributes significantly to the existing theoretical literature on extractive cultures through the development and application of the concept of ‘capture’, which is employed in throughout and which constitutes a central concept the project. The concept of ‘regulatory capture’ informs much of the existing sociological literature on harmful industry. Expanding on the concept of ‘capture’, I consider the capture of Appalachian economies by a single industry (economic capture), the capture of cultural production by the dominant industry (cultural capture), the legal capture of material landscapes by industry (ecological capture), the visual-mechanical capture of images of ecology and culture (photographic capture), and finally, the capture of ecology and people by an emerging industry of incarceration (carceral capture).
153

The 'return' of British-born Cypriots to Cyprus : a narrative ethnography

Teerling, Janine C. J. January 2011 (has links)
My thesis is the product of an in-depth qualitative study of the ‘return' of British-born Cypriots to Cyprus. By specifically focusing on the second generation, my thesis seeks to rectify the lacuna in research on the second generation's connections to the ethnic homeland, capitalising on these migrants' positionalities with respect to questions of home and belonging. The thesis consists of eight chapters: Chapter 1 introduces the context in which the research was conducted; Chapter 2 provides the historical and geographical background for the Cypriot migration experience; Chapter 3 presents the methodological and ethical context in which my research was conducted; Chapters, 4, 5, 6 are the main empirical chapters, discussing the British-born Greek-Cypriot returnees' experiences, motives and viewpoints, from childhood memories to today's adult experiences; Chapter 7 provides an additional comparative angle through the inclusion of a subsample of British-born Turkish Cypriots; and finally, Chapter 8, my concluding chapter, revisits the research questions, draws comparisons with other empirical studies on second-generation return, and re-evaluates my methodological framework. Through the voices and life-narratives of second-generation British-Cypriot ‘return' migrants – following a biographical timeline – the multifaceted perspectives in which notions of ‘return', ‘home' and ‘belonging' can be viewed and experienced in a migratory context are revealed. My study shows the complexities and ambivalences involved when exploring ideas of ‘identity' and ‘return', views of ‘home', and feelings of ‘belonging' in the ancestral homeland – demonstrating how boundaries of such notions are blurred, eroded and re-established by a new generation of migrants, reflecting their time, experiences, choices and ideologies. My findings deconstruct the meaning of ‘return', move beyond the primordial cultural confines of notions of ‘belonging', and challenge the simple dichotomy of ‘home' versus ‘away', revealing new similarities (and differences) beyond such predefined labels and categories, which form the building blocks for new, contemporary, ways and spaces of belonging.
154

O sentido da ontologia do espaço para a dissolução da dicotomia geografia física geografia humana: estudo sobre o caso da geografia crítica brasileira a partir do pensamento de Martin Heidegger

Calçavara, Reginaldo Alex 26 August 2013 (has links)
Made available in DSpace on 2016-12-23T14:20:37Z (GMT). No. of bitstreams: 1 Reginaldo Alex Calcavara.pdf: 2029583 bytes, checksum: 1eb772d96a68609843a4414a83ede253 (MD5) Previous issue date: 2013-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A pesquisa articula os temas da ontologia do espaço e a dicotomia entre a Geografia Física e a Geografia Humana no âmbito do movimento de renovação crítica da geografia brasileira. Busca demonstrar que há um nexo entre a posição assumida por esta vertente da geografia brasileira frente à referida dicotomia e a reflexão ontológica acerca do objeto da disciplina, diretamente influenciada pelo pensamento marxista. Indica como campo alternativo de reflexão ontológica a abordagem do filósofo alemão Martin Heidegger em torno da questão do ser, destacando, dentro da amplitude e centralidade deste assunto na obra do referido filósofo, a perspectiva da questão da técnica que, redimensionando a noção de produção, permitiria oferecer um horizonte alternativo para a ontologia na geografia capaz, sugere-se, de abrir a questão do ser enquanto questão a ser pensada / The study articulates the themes of ontology of space and the dichotomy between Physical Geography and Human Geography in the renewal movement critical of Brazilian geography. Seeks to demonstrate that there is a link between, on the one hand, the position taken by this part of Brazilian geography forward that dichotomy, and on the other hand, the ontological reflection about the object of discipline, directly influenced by Marxism. Indicates how alternative field of ontological thinking approach of the German philosopher Martin Heidegger on the question of being, especially within the scope and centrality of this issue in the work of that philosopher s perspective the question of technique, redefining the notion of production, would provide a horizon alternative ontology in geography capable, it is suggested, opening the question of being as a question to be thought
155

Tenure and vulnerability : the effects of changes to tenure security on the identity and social relationships of the urban poor

Patel, Kamna January 2012 (has links)
Directed by the Millennium Development Goal to improve the lives of at least 100 million ‘slum’ dwellers by 2020, national governments and development agencies are driving policy to upgrade and formalise informal settlements. This study is an investigation into the effects of in situ upgrade and formalisation on the vulnerability and resilience of the urban poor in Durban, South Africa. The study examines the relationships between tenure and vulnerability by identifying and exploring how changes to tenure security, introduced through the upgrade process, affect individuals’ exposure to risk and ability to cope, and the ways in which identity and social relations influence those effects. The data are drawn from twenty-four ethnographies of residents living in three low income settlements in/around Durban each at different stages in the upgrade process. The findings of the study show that many residents are better off following an upgrade – ownership claims are better protected, they are more comfortable in their homes and able to improve livelihoods. However, these security and resilience gains are undermined by the high levels of crime and violence that continue post-upgrade and affect the desirability of a location and the ability of people to live there. Furthermore, the manner in which the process is implemented reconfigures local power relations, without meaningfully altering them; thus continuing to tie residents’ wellbeing to social rules administered by informal institutions. These findings challenge conceptualisations of ‘tenure security’ and the conventional orthodoxy of upgrading.
156

Polybrominated diphenyl ethers (PBDEs) in indoor and outdoor environments

Muenhor, Dudsadee January 2011 (has links)
PBDEs were detected in all air and dust samples. The PBDE congener profile in both outdoor and indoor air samples from Thai e-waste storage facilities and homes was dominated by BDE-47 and 99, whilst the predominant BFRs in all dust samples from Thai e-waste storage facilities were BDE-209, BDE-208, BDE-207, BDE-206, BDE-197, BDE-183, BDE-99, BDE-47 and DBDPE. Furthermore, BDEs 99 and 47 were the most abundant congeners in all dust samples from Thai houses and cars and UK homes. Under realistic high-end scenarios of occupational exposure to BDE-99 via dust ingestion, workers in Thai e-waste storage facilities were exposed above a recently-published Health Based Limit Value for this congener. For non-occupational exposure, under a high-end exposure scenario, the exposure to BDE-99 of such Thai children via dust ingestion is either very close to or in exceedance of the HBLV. PBDE levels in most of the areas monitored within the same rooms were not statistically significantly different. Similarly, concentrations of PBDEs in the majority of rooms within the same houses were not statistically significantly different between rooms. Possible dilution of PBDE levels in dust with increasing dust loadings has been identified in a small number of rooms.
157

An Evaluation Of Clustering And Districting Models For Household Socio-economic Indicators In Address-based Population Register System

Ozcan Yavuzoglu, Seyma 01 December 2009 (has links) (PDF)
Census operations are very important events in the history of a nation. These operations cover every bit of land and property of the country and its citizens. Census data is also known as demographic data providing valuable information to various users, particularly planners to know the trends in the key areas. Since 2006, Turkey aims to produce this census data not as &ldquo / de-facto&rdquo / (static) but as &ldquo / de-jure&rdquo / (real-time) by the new Address Based Register Information System (ABPRS). Besides, by this new register based census, personal information is matched with their address information and censuses gained a spatial dimension. Data obtained from this kind of a system can be a great input for the creation of &ldquo / small statistical areas (SSAs)&rdquo / which can compose of street blocks or any other small geographical unit to which social data can be referenced and to establish a complete census geography for Turkey. Because, statistics on large administrative units are only necessary for policy design only at an extremely abstracted level of analysis which is far from &quot / real&quot / problems as experienced by individuals. In this thesis, it is aimed to employ some spatial clustering and districting methodologies to automatically produce SSAs which are basically built upon the ABPRS data that is geo-referenced with the aid of geographical information systems (GIS) and thus help improving the census geography concept which is limited with only higher level administrative boundaries in Turkey. In order to have a clear idea of what strategy to choose for its realization, small area identification criteria and methodologies are searched by looking into the United Nations&rsquo / recommendations and by taking some national and international applications into consideration. In addition, spatial clustering methods are examined for obtaining SSAs which fulfills these criteria in an automated fashion. Simulated annealing on k-means clustering, only k-means clustering and simulated annealing on k-means clustering of Self-Organizing Map (SOM) unified distances are deemed as suitable methods. Then these methods are implemented on parcel and block datasets having either raw data or socio-economic status (SES) indices in nine neighborhoods of Ke&ccedil / i&ouml / ren whose graphical and non-graphical raw data are manipulated, geo-referenced and combined in common basemaps. Consequently, simulated annealing refinement on k-means clustering of SOM u-distances is selected as the optimum method for constructing SSAs for all datasets after making a comparative quality assessment study which allows us to see how much each method obeyed the basic criteria of small area identification while creating SSA layers.
158

Pleins étiquetages et configurations équilibrées : aspects topologiques de l'Optimisation Combinatoire

Meunier, Frédéric 15 July 2006 (has links) (PDF)
Cette thèse traite principalement des contreparties combinatoires et constructives de certains théorèmes d'optimisation combinatoire qui font appel à des outils de topologie algébrique. Des généralisations des lemmes de Sperner et des formules combinatoires de Ky Fan sont proposées, ainsi que des applications à la coloration des graphes de Kneser et au célèbre problème du partage équitable du collier. Un problème d'ordonnancement lié à ce dernier problème est également abordé. Enfin, le dernier chapitre contient des résultats nouveaux pour les sigma-jeux (jeux de lampes) sur la grille.
159

Developing an enriched natural language grammar for prosodically-improved concent-to-speech synthesis

Marais, Laurette 04 1900 (has links)
The need for interacting with machines using spoken natural language is growing, along with the expectation that synthetic speech in this context sound natural. Such interaction includes answering questions, where prosody plays an important role in producing natural English synthetic speech by communicating the information structure of utterances. CCG is a theoretical framework that exploits the notion that, in English, information structure, prosodic structure and syntactic structure are isomorphic. This provides a way to convert a semantic representation of an utterance into a prosodically natural spoken utterance. GF is a framework for writing grammars, where abstract tree structures capture the semantic structure and concrete grammars render these structures in linearised strings. This research combines these frameworks to develop a system that converts semantic representations of utterances into linearised strings of natural language that are marked up to inform the prosody-generating component of a speech synthesis system. / Computing / M. Sc. (Computing)
160

Desenvolvimento de métodos analíticos para a determinação de metais traço em vegetais da família Solanaceae por espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos.

Siqueira, Marianna Pozzatti Martins de January 2017 (has links)
Neste trabalho foram desenvolvidos quatro métodos analíticos para a determinação de cádmio, cromo, cobre, níquel e ferro em vegetais da família Solanaceae, cultivados pelos métodos convencional e orgânico de produção, obtidos em feiras e mercados da cidade de Porto Alegre, Brasil. Estes vegetais são muito consumidos devido a grande quantidade de nutrientes, no entanto, podem ser contaminados por elementos potencialmente tóxicos, por meio da exposição a poluição, uso de pesticidas, fertilizantes e água contaminada. As determinações foram conduzidas pela técnica de espectrometria de absorção atômica de alta resolução com fonte contínua em forno de grafite por análise direta de sólidos. Para Cd, Cr e Cu foram desenvolvidos três métodos independentes. No caso da determinação de Ni e Fe foi realizada análise simultânea, empregando linhas analíticas alternativas. Temperaturas de pirólise e atomização foram otimizadas para todos os elementos analisados, visando sinais analíticos com elevada sensibilidade e livres de interferências. Os métodos otimizados foram aplicados em amostras de pimentão, batata, tomate, berinjela, pimenta e physalis. Várias amostras apresentaram concentrações superiores aos limites máximos estabelecidos por legislações específicas. Os métodos propostos envolveram mínimo preparo de amostra, reduzindo riscos de contaminação, tempo analítico e custos, além de demonstrarem-se simples, precisos, rápidos e sensíveis. / In this work, four methods have been developed for the determination of cadmium, chromium, copper, nickel and iron in vegetables of the Solanaceae family, cultivated in conventional and organic farming systems, obtained from local markets and local farms, located in the city of Porto Alegre, Brazil. These vegetables are much appreciate due to the large amount of nutrients present in it. However, vegetables can be contaminated by potentially toxic elements, through the exposure to pollution, use of pesticide, fertilizers and contaminated water. The assays were carried out using a high-resolution continuum source graphite furnace atomic absorption spectrometer and direct solid sample analysis. Cd, Cr and Cu had their methods individually developed. In the case of the determination of Ni and Fe, it was applied simultaneous analysis, employing alternative analytical lines. Pyrolysis and atomization temperatures were optimized for all target elements, aiming for analytical signals with high sensitivity and free from interferences. The optimized methods were applied in samples of bell peppers, potato, tomato, eggplant, pepper and physalis. Several samples presented concentrations above the maximum permitted by specific legislation. The proposed methods were accurate, simple, fast and sensitive; moreover, a minimum sample preparation was necessary, reducing contamination, analytical time and costs.

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