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Writing the Ethics of Water in Michael Ondaatje, Thomas King, and Anne MichaelsGallant, Laura 02 September 2010 (has links)
In July 2010, the United Nations declared access to water and sanitation a human
right. Certainly a success for water rights advocates worldwide, this resolution also poses
a number of questions, such as how to find and distribute this water on a planet that is
running out of fresh water (Barlow et al, Blue Gold xi). With this question in mind, this
thesis looks at the treatment of water management projects in Michael Ondaatje’s In the
Skin of a Lion (1987), Thomas King’s Green Grass, Running Water (1993), and Anne
Michaels’ The Winter Vault (2009). More specifically, it examines the ways competing
visions of the common good and of what development should (and should not) look like
are imbricated therein. In so doing, my discussion focuses on the inextricability of social
justice from water justice and it suggests that narrative can play a key role in connecting
the two.
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Design of a Dynamic Boom Suspension System in a Hybrid Wheel LoaderAyoub, Ayoub, Berg, Carl Martin January 2018 (has links)
Wheel loaders are under the influence of low frequency vibrations that may be harmful for the health of the operator, and for the productivity of the machine. The strong vibrations can significantly impact the operation of the machine since they are not equipped with wheel suspension systems and due to their work environment in rough terrains with uneven surfaces. The risk of spilling or dropping the load is also increased and they can introduce higher mechanical stress that can wear out parts faster. The focus of this thesis work is to develop an approach for damping these vibrations dynamically by improving the functionality of the electrohydraulic system in Volvo's prototype wheel loader LX1. The dynamic damping system controls the cylinder of the lift framework to make it behave as a damper. The system utilizes the lift cylinder pressure and piston position as feedback to adjust the oil flow in the cylinder using the proposed control system. Results indicate that the proposed technique is capable of attenuation that is comparable with the existing boom suspension system based on accumulators through simulations and experimental tests.
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DiagnÃstico de Aspectos Socioambientais da Microbacia do AÃude do Arriba - Forquilha - CE / Diagnosis of environmental aspects of the watershed of Arribita - Forquilha/CEDeborah de Andrade AragÃo 27 May 2011 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / The circunstances provoked by droughts on the semi-arid of the northeastern region of Brazil, assumed along the history, a unavoidable character that led to the adoption of politics related to the construction of hydric reservoirs as an attempt to mitigate the effects of drought. However, the construction of a great number of reservoirs, done in a random way, without observing its framing to the conditions of the hydric dynamics as well as its yours support capacity, allied to an ocupation, motivated by the offer of water, ended up inserting itself in the context of socioenvironmental problematic. The analysis of the decision process in allocating different uses for water involves several dificulties which characterizes the present context. Among the most important are the necessary interdisciplinar approach to the subject matter, the subjectivity of the agents involved in the process of water management, the randomness of the hydrologic events, the uncertainty of the economic, social and environmental processes, the difficulties in measuring such variables as social well-being and environmental protection and others as cultural and aesthetics, besides the traditional problem of measuring economic efficiency. This dissertation presents, examines and compare some techniques of socioenvironmental analysis as important support tools for decision-making in water management. Therefore, the integration of hydric resources management through the institution of hydric basins as an unit of management should consider as prioritary manner, the question of damming as concern to the northeastern hydric resources, in special, the ones of small size, that support directly the local communities and which are more seriously affected by the degradation generated by antropic actions as well as inadequate use. / As circunstÃncias provocadas pelas secas no semi-Ãrido nordestino assumiram, ao longo da histÃria, um carÃter inevitÃvel que levou a doÃÃo de uma polÃtica voltada para a construÃÃo de reservatÃrios hÃdricos na tentativa de mitigar os efeitos da estiagem. No entanto, a construÃÃo de um grande nÃmero de reservatÃrios elaborada de maneira aleatÃria, sem observar seu enquadramento nas condiÃÃes na dinÃmica hÃdrica nem em sua capacidade de suporte, aliada a uma ocupaÃÃo motivada pela oferta de Ãgua acabaram por se inserir no contexto de problemÃtica socioambiental. O uso mÃltiplo das Ãguas, o carÃter multidisciplinar e subjetivo dos agentes envolvidos no processo, a aleatoriedade dos eventos hidrolÃgicos, a incerteza dos processos econÃmicos, sociais e ambientais, a necessÃria consideraÃÃo de aspectos de difÃcil mensuraÃÃo, como o bem estar social, a preservaÃÃo do ambiente e as questÃes culturais e estÃticas, alÃm da tradicional eficiÃncia econÃmica, caracterizam o contexto presente. Este trabalho apresenta, descreve e compara algumas tÃcnicas de anÃlise socioambiental como importante meio de apoio à tomada de decisÃes diante dos problemas de gestÃo das Ãguas. Portanto, a integraÃÃo do gerenciamento dos recursos hÃdricos atravÃs da instituiÃÃo das bacias hidrogrÃficas como unidade de gestÃo deve considerar de maneira prioritÃria a questÃo da aÃudagem no que diz respeito aos recursos hÃdricos nordestinos, em especial os de pequeno porte que servem de maneira mais direta Ãs comunidades locais e sÃo mais gravemente afetados pela degradaÃÃo gerada pelas aÃÃes antrÃpicas e o uso inadequado.
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Assessment of Model Forecast Temperature Bias During Cold Air Damming in the Central Appalachian MountainsLindeman, Suzanna Alison 06 June 2018 (has links)
Cold-air damming (CAD) is a prevalent Mid-Atlantic United States weather phenomenon that occurs when cold, dense air is dammed alongside the eastern slopes of the Appalachian Mountains. Lower-than-normal maximum temperatures, increased and prolonged cloud cover, and precipitation that produces hazardous impacts are common features of this weather event, which are well known for presenting difficulties to both human forecasters and weather prediction models. This study explores CAD events between 2007 and 2016 archived in a Blacksburg National Weather Service ‘bust’ database – instances when forecasters erred by at least 8°F (4.4°C) on either maximum or minimum daily air temperature. The database includes the temperature error within Model Output Statistics (MOS) guidance in association with these forecast ‘busts.’ During the 10-year study period, MOS guidance produced warm-biased maximum temperatures and cold-biased minimum temperatures for most of the problematic CAD events, suggesting MOS guidance tended to underestimate the strength of CAD in these cases, seeming to struggle with weaker CAD events. During CAD erosion, MOS tended to prematurely erode CAD scenarios at night and predicted them to persist for too long during the day. Hourly surface meteorological and synoptic atmosphere composites during these ‘busted’ CAD events failed to reveal obvious differences from what is expected for central Appalachian CAD. However, a comparison to well-forecast classic cold-season CAD events suggest that busted cases of this same type of CAD may be drier than is typical. As the atmospheric patterns associated with busted CAD events are typical of the phenomenon, but a bit weaker or more marginal, forecast errors appear to stem from subtle model errors rather than forecaster error. It is possible that the models may inadequately characterize low-level moisture, but further research is needed to isolate the source of model forecast error. Nonetheless, the results of this research serve as guidance for operational forecasters as they consider model guidance during weak CAD events. / Master of Science / Cold-air damming (CAD) is a common weather pattern that affects the Blue Ridge Mountain region of the eastern United States, in which cold air at the atmosphere’s surface is directed from the Northeast and is dammed against the eastern Appalachian Mountains. This weather event causes lower-than-normal temperatures over the region and is often characterized by prolonged cloudy skies and precipitation. CAD is very difficult for forecasters to accurately predict, as they rely on weather forecast models that often simulate these situations poorly. CAD also strains emergency managers who rely on accurate forecasts to support public safety during CAD. This study explores CAD events between 2007 and 2016 archived in a Blacksburg National Weather Service ‘bust’ database – instances when forecasters erred by at least 8°F (4.4°C) on either maximum or minimum daily air temperature. The database includes the temperature error within Model Output Statistics (MOS) guidance in association with these forecast ‘busts.’ During the 10-year study period, MOS guidance forecasted maximum temperatures too high and minimum temperatures too low for most of the problematic CAD events, suggesting MOS guidance tended to underestimate the strength of CAD in these cases, seeming to struggle with weaker CAD events. During instances where CAD dissolved from the Appalachians, MOS tended to prematurely erode CAD scenarios at night and predicted them to persist for too long during the day. Hourly surface meteorological and synoptic atmosphere composites during these ‘busted’ CAD events failed to reveal obvious differences from what is expected for central Appalachian CAD. However, a comparison to well-forecast classic cold-season CAD events suggest that busted cases of this same type of CAD may be drier than is typical. As the atmospheric patterns associated with busted CAD events are typical of the phenomenon, but a bit weaker or more marginal, forecast errors appear to stem from subtle model errors rather than forecaster error. It is possible that the models may inadequately characterize low-level moisture, but further research is needed to isolate the source of model forecast error. Nonetheless, the results of this research serve as guidance for operational forecasters as they consider model guidance during weak CAD events.
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Diagnóstico de Aspectos Socioambientais da Microbacia do Açude do Arriba - Forquilha - CE / Diagnosis of environmental aspects of the watershed of Arribita - Forquilha/CEAragão, Deborah de Andrade January 2011 (has links)
Aragão, Deborah de Andrade Aragão. Diagnóstico de Aspectos Socioambientais da Microbacia do Açude do Arriba - Forquilha - CE. 2011. 165 f. : Tese (doutorado) - Universidade Federal do Ceará, Pró-Reitoria de pesquisa e Pós-Graduação, Programa Regional de Pós-Graduação em Desenvolvimento e Meio Ambiente - PRODEMA, Fortaleza-CE, 2011 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-13T14:52:21Z
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Previous issue date: 2011 / The circunstances provoked by droughts on the semi-arid of the northeastern region of Brazil, assumed along the history, a unavoidable character that led to the adoption of politics related to the construction of hydric reservoirs as an attempt to mitigate the effects of drought. However, the construction of a great number of reservoirs, done in a random way, without observing its framing to the conditions of the hydric dynamics as well as its yours support capacity, allied to an ocupation, motivated by the offer of water, ended up inserting itself in the context of socioenvironmental problematic. The analysis of the decision process in allocating different uses for water involves several dificulties which characterizes the present context. Among the most important are the necessary interdisciplinar approach to the subject matter, the subjectivity of the agents involved in the process of water management, the randomness of the hydrologic events, the uncertainty of the economic, social and environmental processes, the difficulties in measuring such variables as social well-being and environmental protection and others as cultural and aesthetics, besides the traditional problem of measuring economic efficiency. This dissertation presents, examines and compare some techniques of socioenvironmental analysis as important support tools for decision-making in water management. Therefore, the integration of hydric resources management through the institution of hydric basins as an unit of management should consider as prioritary manner, the question of damming as concern to the northeastern hydric resources, in special, the ones of small size, that support directly the local communities and which are more seriously affected by the degradation generated by antropic actions as well as inadequate use. / As circunstâncias provocadas pelas secas no semi-árido nordestino assumiram, ao longo da história, um caráter inevitável que levou a doção de uma política voltada para a construção de reservatórios hídricos na tentativa de mitigar os efeitos da estiagem. No entanto, a construção de um grande número de reservatórios elaborada de maneira aleatória, sem observar seu enquadramento nas condições na dinâmica hídrica nem em sua capacidade de suporte, aliada a uma ocupação motivada pela oferta de água acabaram por se inserir no contexto de problemática socioambiental. O uso múltiplo das águas, o caráter multidisciplinar e subjetivo dos agentes envolvidos no processo, a aleatoriedade dos eventos hidrológicos, a incerteza dos processos econômicos, sociais e ambientais, a necessária consideração de aspectos de difícil mensuração, como o bem estar social, a preservação do ambiente e as questões culturais e estéticas, além da tradicional eficiência econômica, caracterizam o contexto presente. Este trabalho apresenta, descreve e compara algumas técnicas de análise socioambiental como importante meio de apoio à tomada de decisões diante dos problemas de gestão das águas. Portanto, a integração do gerenciamento dos recursos hídricos através da instituição das bacias hidrográficas como unidade de gestão deve considerar de maneira prioritária a questão da açudagem no que diz respeito aos recursos hídricos nordestinos, em especial os de pequeno porte que servem de maneira mais direta às comunidades locais e são mais gravemente afetados pela degradação gerada pelas ações antrópicas e o uso inadequado.
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Padrões estruturais de florestas montanas sob influência de um empreendimento hidrelétrico no sul do BrasilUrruth, Leonardo Marques 23 August 2011 (has links)
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Previous issue date: 2011 / Nenhuma / Fatores topográficos afetam as comunidades vegetais em diferentes escalas espaciais agindo como filtros para a distribuição e abundância das espécies. Essa influência é proeminente em ecossistemas montanos. No sul do Brasil as encostas íngremes dos rios da bacia hidrográfica do rio Pelotas abrigam importantes remanescentes florestais montanos, apesar da pressão antrópica histórica exercida pela extração madeireira, agropecuária, silvicultura e nas últimas décadas, principalmente pela exploração hidrelétrica. O represamento de rios é um dos mais proeminentes impactos aos ecossistemas de água doce, com reflexos sobre a vegetação ripária. A construção de reservatórios hidrelétricos em rios montanos com vales estreitos como aqueles da bacia hidrográfica do rio Pelotas causa a elevação artificial do nível e do lençol freático podendo afetar a vegetação ripária situada acima do novo nível dos rios. Portanto são esperadas diferenças estruturais entre florestas de encosta que margeiam reservatórios hidrelétricos e áreas controle. Este estudo foi desenvolvido em florestas de encosta de três tributários do rio Pelotas, em Campo Belo do Sul, SC. Foram instaladas 90 unidades amostrais (0,9 ha) em encostas que margeiam o reservatório da UHE Barra Grande e em encostas controle. Foram amostradas todas as árvores e arbustos vivos com DAP ≥ 5 cm. O desenho amostral permitiu comparar a heterogeneidade topográfica, a estrutura florestal e a composição de espécies (separadamente) entre rios, e em cada um deles o tratamento efeito da barragem através de análises de variância uni e multivariadas. Também foi utilizada uma análise de espécies indicadoras para determinar as espécies mais afins a cada encosta. A riqueza de espécies foi comparada por meio de curvas de rarefação baseadas na amostra. Neste trabalho foi utilizado o conceito de número efetivo de espécies (diversidade verdadeira) para calcular a diversidade de árvores. Foram amostradas 1233 árvores de 87 espécies e 40 famílias. As análises estatísticas revelaram heterogeneidade topográfica entre as encostas, que se refletiu na estrutura florestal e na composição de espécies. Essas diferenças também foram observadas em cada um dos rios para o tratamento efeito da barragem. Riqueza e diversidade de espécies se mostraram relativamente homogêneas. Os resultados corroboram o papel da heterogeneidade ambiental na estruturação das comunidades. As diferenças estruturais e em composição de espécies observadas para o tratamento efeito da barragem sugerem efeitos sobre a vegetação. Por outro lado, múltiplos fatores podem ter relações causais com essas diferenças, e, portanto, são necessários estudos complementares. / Plant communities are affected by topography in different spatial scales, acting as an environmental filter to species distribution and abundance. This influence is prominent in montane ecosystems. In southern Brazil, steep slopes of the Pelotas river watershed has important montane forest remnants, despite the pressure exerted by anthropic historical logging, agriculture, forestry, and in recent decades, hydroelectric exploitation. The damming of rivers is one of the most prominent impacts on freshwater ecosystems, with impacts on the riparian vegetation. The hydroelectric reservoir construction in a montane river with narrow valleys like those of the Pelotas river watershed causes the artificial increase of river water level and the groundwater affecting the riparian vegetation located above the new level of rivers. So, are expected structural differences between slope forest bordering Barra Grande hydroelectric reservoir and control areas. This study was carried out in slope forests of the three tributaries of Pelotas river in Campo Belo do Sul, SC. Were installed 90 sample plots (0.9 ha) on slope forests bordering the reservoir and control areas. We sampled all trees and shrubs alive with DBH ≥ 5 cm. The sample design allowed us to compare topography, forest structure and species composition (separately) between rivers, and the effect of the dam treatment through univariate and multivariate analysis of variance. It was also used an indicator species analysis to determine indicator species to each slope. Species richness was compared using rarefaction curves based on the sample. In this study we used the concept of effective number of species (true diversity) to calculate trees diversity. We sampled 1233 trees of 87 species and 40 families. Statistical analysis revealed topographic heterogeneity among the slopes, which was reflected in forest structure and species composition. These differences were also observed in each of the rivers for the effect of the dam treatment. Richness and true diversity proved relatively homogeneous. Our results support the role of environmental heterogeneity on forest communities. The forest structure and species composition differences observed for the effect of the dam treatment suggest effects on vegetation. On the other hand, multiple factors may have causal relationships with these differences, and therefore further studies are needed.
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Artificial reservoirs affect tree functional components of tropical dry forestsNascimento, Diego Raymundo 16 February 2017 (has links)
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Previous issue date: 2017-02-16 / A construção de barragens é uma das principais formas em que o ser humano altera
os ecossistemas. Entender como reservatórios advindos da barragem afetam florestas tropicais
secas é essencial, uma vez que essas florestas estão localizadas em áreas de alto impacto de
barragens no mundo. Nosso objetivo foi avaliar até que ponto reservatórios podem afetar
mudanças na estrutura, diversidade taxonômica e componentes da diversidade funcional de
florestas secas após 10 anos da construção de uma barragem. Em fragmentos de florestas
tropicais secas nós apresentamos dados de dinâmica temporal de 120 parcelas permanentes
que estavam longe (>700 m) do curso de água antes do represamento, e agora estão na borda
(0 to 60 m) do reservatório. Parcelas mais próximas ao reservatório apresentaram um maior
aumento na diversidade funcional, mas não apresentaram relações significativas na
diversidade taxonômica. Parcelas próximas ao reservatório também apresentaram uma maior
diminuição em densidade de madeira (relacionado com alta disponibilidade de água) e uma
maior diminuição em área foliar específica e maior aumento de indivíduos com folhas
compostas (possivelmente relacionado à maior disponibilidade de luz, criada pela borda do
reservatório). Nossos resultados sugerem que reservatórios podem alterar a funcionalidade de
florestas tropicais secas ao longo do tempo e evidencia a importância de mais estudos que
relacionem essas mudanças com processos demográficos. / Reservoir construction is one of the main ways humans alter ecosystems by
damming rivers. Understanding how reservoir dams affect forests is essential once they are
usually in the highest impact areas of the world. We aimed to evaluate to what extent an
artificial reservoir affected changes in the structure, species diversity and components of
functional diversity of a tropical dry forest after 10 years of the dam construction. In the
patches of the tropical dry forest we present dynamic data of 120 permanent plots that were
far (> 700 m) from the watercourse before damming and are now on the edge of it (0 to 60 m).
We evaluated how changes in community structure, taxonomy diversity and functional
components were related with distance of the reservoir shorelines. Plots closer to the reservoir
showed higher increase in functional diversity but do not showed significant relationships
with taxonomy diversity. Plots closer to the reservoir also showed higher decrease in wood
density (related to high water availability), higher decrease in specific leaf area, and increase
in compoundness (possible due to increase in light incidence due to reservoir edge). Our
results suggest that reservoirs can alter functionality of tropical dry forests over time and
highlight the importance of more studies relating these changes with demographic process.
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