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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.
121

Análise da vulnerabilidade à erosão costeira no estado de Pernambuco através de indicadores ambientais e antrópicos

MENEZES, Athos Farias 23 March 2016 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-09-14T19:25:48Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Athos Farias Menezes 2016.pdf: 6385036 bytes, checksum: a2522df55623cf13d58d7d17b4302fb7 (MD5) / Made available in DSpace on 2016-09-14T19:25:48Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Athos Farias Menezes 2016.pdf: 6385036 bytes, checksum: a2522df55623cf13d58d7d17b4302fb7 (MD5) Previous issue date: 2016-03-23 / Facepe / A erosão costeira é um fenômeno natural encontrado em diversos ambientes litorâneos em todo o mundo. No entanto a ocupação antrópica desordenada pode potencializar o processo erosivo, como é o caso do litoral do estado de Pernambuco, onde 43,8% da população está localizada no ambiente litorâneo que se estende ao longo de 13 municípios. Observando esta problemática, o presente trabalho foi desenvolvido com o intuito de avaliara vulnerabilidade à erosão costeira através do processamento de imagens de satélite de alta resolução e sistemas de informações geográficas (SIG),a partir de indicadores ambientais e antrópicos. A presente pesquisa foi dividida em três etapas, a primeira visa caracterizar a vulnerabilidade à erosão costeira em escala local nas praias de Piedade (município de Jaboatão dos Guararapes) e Paiva (município do Cabo de Santo Agostinho), ressaltando as diferentes características atribuídas as mesmas. Na primeira praia destacou-se a intensa urbanização, com mais de 60% de interferência antrópica nos setores avaliados, enquanto a segunda se demonstrou conter um bom desenvolvimento de áreas vegetais preservadas mais de 55% do total analisado. Na segunda etapa, foi mostrado o uso dos geoindicadores em escala regional para todo o litoral pernambucano, destacando cenários de intensa vulnerabilidade nas cidades do núcleo metropolitano, enquanto em praias de baixa presença antrópica, como no setor sul, foram destacados baixos índices de vulnerabilidade, enquanto no setor norte foram atribuídos valores moderados. Na terceira etapa deste trabalho trabalho foi apresentado a utilização da interpretação de imagens de alta resolução espacial e métodos automáticos e semiautomáticos na identificação dos geoindicadores na Praia do Forte Orange (município da Ilha de Itamaracá) evidenciando feições sedimentares oriundas do Canal de Santa Cruz, mas com a presença de feições erosivas. De forma geral este trabalho visualiza destacar a importância de métodos alternativos na identificação de áreas com potenciais erosivos, a partir de dados orbitais que acarretarão em uma otimização do tempo para na tomada de decisões públicas acerca dos ambientes litorâneos. / The coastal erosion is a natural phenomenon found in many coastal environments worldwide. One of the causes of unorganized human occupation near coastal areas is erosion. An example of erosion caused by anthropogenic activities is found in the coastal areas of Pernambuco State, Brazil, where 43.8% of the state population live nearthe state’s coastal environments, extending over 13 cities. The current study is divided in three chapters and focuses on the coastal beaches vulnerability evaluation and identification of the vulnerability of coastal erosion caused by anthropogenic and environmental factors, using tools as high resolution satellite images and geographic information systems. First part aims to characterize the vulnerability of beaches to coastal erosion in a local scale.The areas of study are Piedade (city of Jaboatão dos Guararapes) and Paiva beaches (city of Cabo de Santo Agostinho) in Pernambuco State, Brazil, with geomorphological and dynamic characteristics variablity. Piedade beach has intensive urbanization, indicating more than 60% of anthropogenic interference in all evaluated sectors, while Paiya beachis covered by vegetation approximately 55% of total area. In second part, several geoindicators were analyzed in a regional scale along the Pernambuco’s coastline. Different scenarios of high vulnerability were examined in the cities of the metropolitan area, on beaches of low and high anthropogenic activities. The first results, showed low indication of vulnerability at the southen sectorcompared to the northen sector which showed moderate risk of erosion. Finally, in section three,high resolution satellite images were used to identify geoindicators by automaticand semi-automatic approaches in order to identify erosional features. In this chapter the study the Forte Orange beach (city of Ilha de Itamaraca) highlighting sedimentary features of the Canal de Santa Cruz and the presence of erosional features. This research highlights the importance of alternative identification methods for areas under potential erosion risk. The proposed methods in this study are very efficient and can produce accurate and fast results, which can be valuable to the public, environmental agencies, porotection and decision makers of coastal environments.
122

Medidas mitigadoras de ocorrência de movimentos de massa e plano de revegetação de uma encosta no município de São Sebastião/SP / Mitigating measures of occurence of mass movements and plan of vegetation renewal of a hillside in the municipality of São Sebastião/SP

Marco Antonio Alves Garcia 11 March 2005 (has links)
Este estudo foi realizado em uma clareira, um fragmento de Mata Atlântica de 4,8 hectares localizado no município de São Sebastião - SP, de propriedade da Universidade São Marcos, com o objetivo de fornecer subsídios sobre as atividades de sua recomposição vegetal, de modo que possa prevenir e/ou reduzir os riscos de escorregamentos na encosta. As metodologias disponíveis e mais adequadas para diagnóstico de áreas frágeis e com risco de escorregamento foram expressas em cartas geotécnicas. Outro aspecto metodológico que mereceu destaque refere-se à análise dos elementos (fisiográficos e antrópicos) que compõem o terreno analisado. Para a etapa de compartimentação do terreno existem duas abordagens básicas: a paramétrica e a fisiográfica. Na primeira foram feitas associações de temas representados em mapas específicos (por exemplo, mapas de relevo, geológico, geomorfológico). A abordagem fisiográfica foi avaliada quanto a suscetibilidade à ocorrência de movimentos de massa. A modelagem para o reflorestamento é o plantio heterogêneo, que consiste na prática de se plantar o conjunto de diferentes espécies numa mesma área, recriando condições, mais próximos possível da mata atual. Assim, foi realizado um levantamento fitossociológico no fragmento de entorno da clareira à fim de subsidiar a seleção de espécies para a recomposição vegetal. A seleção de espécies (50% de crescimento rápido) foi feita visando a interrupção do processo de erosão e, conseqüentemente, como medida de prevenção ao escorregamento da encosta. Com a proposta aqui realizada pretende-se ainda que, o modelo resulte como potencial de extrapolação para outras áreas de floresta ombrófila densa de encosta. / This study was carried out in an opening, a 4.8 hectares fragment of Mata Atlântica located in the municipality of São Sebastião-SP and owned by the University São Marcos, with the goal of providing subsidies about the vegetation renewal activities in such a way that the risk of hillside sliding can be avoided. The available and most appropriate methodologies for the diagnosis of fragile areas with a sliding risk were explained in the geotechnical charters. Another note-worthy methodological aspect is the analysis of the elements (physiographical and anthropic) which are part of the analyzed terrain. There are two basic approaches for the compartmentalization phase of the terrain: the parametric and the physiographic. In the first, the correspondence of topics represented in specific maps (for example, relief, geological and geomorphological maps) was made. The physiographic approach was evaluated for its susceptibility to the occurrence of mass movements. The modeling for the reforestation is heterogeneous planting, which consists in planting a set of different species in the same area, recreating conditions most like the current vegetation. Thus, a phytosociological survey was carried out in the fragment surrounding the opening in order to give subsidies for the selection of species for plant renewal. The species were selected (50% rapid growing species) with the goal of interrupting the erosion process and, as a result, as preventive measure against hillside sliding. The intention is this proposal can be has potential to be extrapolated to other dense ombrophylous forests in cliffs.
123

Asphalt Perpetual Pavement Design: Utilizing Existing Pavement Systems in Ohio

Jordan, Benjamin B. 13 June 2013 (has links)
No description available.
124

The Comparability of Happiness and Life Satisfaction: A Life Course Approach

Bardo, Anthony Richard 03 May 2010 (has links)
No description available.
125

A Geotechnical Investigation of the October 2011 Cedar City Landslide, Utah

Tizzano, Ashley S. 24 April 2014 (has links)
No description available.
126

Navigation in GPS Challenged Environments Based Upon Ranging Imagery

Markiel, JN M. 27 August 2012 (has links)
No description available.
127

Decision Tree for Ground Improvement in Transportation Applications

Yenco, Aileen C. January 2013 (has links)
No description available.
128

Experimental investigation of the sand-stabilization potential of a plant-derived bio-mass

Bartley, Paul Andrew January 1900 (has links)
Master of Science / Department of Civil Engineering / Dunja Peric / The main objective of this study was to experimentally investigate the Mohr-Coulomb strength parameters of masonry sand mixed with varying amounts of water and lignin. Lignin is a plant-derived biomass, which is a co-product of bio-fuel production. It exhibits binding qualities when mixed with water thus making it an ideal candidate for sustainable non-traditional sand stabilization. An experimental program was devised and carried out to quantify the compaction and early age stress-strain and dilatancy responses of sand-lignin mixes. The program included sieve analysis, Atterberg limit tests, standard Proctor tests, and direct shear tests. The experimental results were used to find the cohesion and the angle of internal friction of the tested material, therefore determining the influence of the amount of lignin and water on the strength of the samples. An extensive data analysis was subsequently completed to gain deeper understanding of the underlying strength gain mechanism. It was found that the normalized cohesion benefit due to lignin is controlled by two variables; water to lignin ratio and void ratio. The lignin and water create a paste, which provides particle bonding at the contacts of sand particles, thus increasing the stress-bearing cross sectional area. Increase in the portion of cross-sectional area occupied by water and lignin normalized by gravimetric lignin content, increases the normalized cohesion up to a point, while the cohesion per gravimetric lignin content decreases with the increasing area ratio. This in turn indicates that cohesion increases only up to 6% of lignin, beyond which it starts to decrease due to the presence of too much fine material within the pores. The presence of lignin in the pores consistently decreases the angle of internal friction. However, for all configurations with lignin tested herein, cohesion was larger than for dry sand, thus indicating strength benefits at low confining pressures or at normal stresses below the so-called limiting normal stress.
129

Diagnóstico do uso do solo na bacia hidrográfica do Ribeirão do Paraíso no município de São Manuel (SP), por meio de geotecnologias /

Pollo, Ronaldo Alberto, 1966- January 2013 (has links)
Orientador: Zacarias Xavier de Barros / Banca: Lincoln Gehring Cardoso / Banca: Sergio Lazaro de Lima / Resumo: O presente trabalho teve como objetivos principais avaliar num intervalo de 38 anos, por meio de fotografias aéreas referente ao ano de 1972 e imagem TM (Thematic Mapper) do satélite Landsat-5 de 2010, o uso e ocupação do solo, Áreas de Preservação Permanentes (APPs) e seus conflitos de uso, por meio de técnicas de geoprocessamento na bacia hidrográfica do ribeirão Paraíso, município de São Manuel - SP até sua jusante na divisa com o município de Areiópolis-SP. Essa bacia representa grande importância para São Manuel-SP, pois alguns de seus mananciais abastecem a área urbana do município, valendo salientar que uma de suas nascentes está próxima a um local que por muitos anos funcionou como depósito de lixo a céu aberto localizado no divisor de águas e o outro sendo utilizado ao seu redor por pastagem, com a presença de bovinos tendo acesso direto a nascente e este por sua vez está inserido na Área de Proteção Ambiental (APA) Perímetro Botucatu-SP, considerada uma área de recarga do Aquífero Guarani. O desenvolvimento da agricultura nos dias atuais enfrenta desafios, qual seja produzir mais alimentos sem causar impactos ao meio ambiente. Aliados a esta preocupação, as instituições de pesquisa tem buscado novas tecnologias que permitem a detecção e quantificação das ações antrópicas, possibilitando intervenções e minimizando os danos causados ao meio ambiente. Entre estas tecnologias podem ser citados os sistemas de informações geográficas, onde um grande volume de dados e informações armazenadas de uma região em diferentes épocas pode ser avaliado simultaneamente, sugerindo diversas abordagens sobre o planejamento do uso do solo. Os resultados do mapeamento das áreas de uso e ocupação do... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work aimed to analyze, in a 38-year interval, by means of 1972 air photographs and TP (Thematic Mapper) image from the Landsat-5 satellite in the year of 2010, the use and occupation of the land, Permanent Preservation Areas (APPs) and its conflicts of use, by means of techniques of geoprocessing in the Paraíso Stream Watershed, in the county of São Manuel-SP until its downstream in Areiópolis-SP. This watershed has great importance to São Manuel-SP, for some of its springs supply the urban area of the county, and it's important to accentuate that one of its springs is near a place that was used as an open dump for many years, it was located in the watershed and another one was located around it for pasture, with the presence of cattle with straight access to the watershed, which is inserted in the Environment Protection Area (APA) Botucatu Perimeter-SP, considered an area of recharge for the Guarani Aquifer. The development of agriculture, nowadays, faces some challenges, for example, producing more food without harming the environment. Allied to this concern, the research institutions have been looking for new technologies that allow us to detect and quantify anthropogenic actions, enabling interventions and minimizing the harm to the environment. Among these technologies, we can mention the geographic information systems, where a great data volume and stored information of a region in different epochs can be evaluated simultaneously, suggesting several approaches of the land use planning. The results of the mapping of the land using and occupying areas totalized nine sorts of use in 1972, and coffee cultivation represented the greatest occupation (37,94%) of the total of the area. The 2010 mapping resulted in twelve sorts... (Complete abstract click electronic access below) / Mestre
130

Time- stress-compressibility characteristics of cementitiously stabilized organic soils

Unknown Date (has links)
Effect of cementitious stabilization on the stress-compressibility characteristics of three different South Florida organic soils were evaluated in this study. The objectives of the research were to (l) determine if the secondary compression characteristics of organic soils and peats can be stabilized with (a) cement only, (b) binary blends of cement/slag (C-S), cement/gypsum (C-G), and cement/cement-kiln-dust (C-CKD) and (c) ternary blend of cement-slag-gypsum in equal proportions; (ll) quantify the effectiveness of cementitious stabilization by evaluating the time-stress-compressibility (t-log σ'v - e) relationship in terms of the Cα / Cc ratio; and (lll) provide some guidelines for selecting optimum dosage of cementitious materials in deep mixing methods when organic soils and peats are encountered. It was concluded that cementitious mixes containing various waste materials is effective in controlling the secondary compression behavior of organic soils, and therefore should be considered in deep mixing methods as a sustainable practice. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

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