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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.
81

Predictive Data-Derived Bayesian Statistic-Transport Model and Simulator of Sunken Oil Mass

Echavarria Gregory, Maria Angelica 18 August 2010 (has links)
Sunken oil is difficult to locate because remote sensing techniques cannot as yet provide views of sunken oil over large areas. Moreover, the oil may re-suspend and sink with changes in salinity, sediment load, and temperature, making deterministic fate models difficult to deploy and calibrate when even the presence of sunken oil is difficult to assess. For these reasons, together with the expense of field data collection, there is a need for a statistical technique integrating limited data collection with stochastic transport modeling. Predictive Bayesian modeling techniques have been developed and demonstrated for exploiting limited information for decision support in many other applications. These techniques brought to a multi-modal Lagrangian modeling framework, representing a near-real time approach to locating and tracking sunken oil driven by intrinsic physical properties of field data collected following a spill after oil has begun collecting on a relatively flat bay bottom. Methods include (1) development of the conceptual predictive Bayesian model and multi-modal Gaussian computational approach based on theory and literature review; (2) development of an object-oriented programming and combinatorial structure capable of managing data, integration and computation over an uncertain and highly dimensional parameter space; (3) creating a new bi-dimensional approach of the method of images to account for curved shoreline boundaries; (4) confirmation of model capability for locating sunken oil patches using available (partial) real field data and capability for temporal projections near curved boundaries using simulated field data; and (5) development of a stand-alone open-source computer application with graphical user interface capable of calibrating instantaneous oil spill scenarios, obtaining sets maps of relative probability profiles at different prediction times and user-selected geographic areas and resolution, and capable of performing post-processing tasks proper of a basic GIS-like software. The result is a predictive Bayesian multi-modal Gaussian model, SOSim (Sunken Oil Simulator) Version 1.0rc1, operational for use with limited, randomly-sampled, available subjective and numeric data on sunken oil concentrations and locations in relatively flat-bottomed bays. The SOSim model represents a new approach, coupling a Lagrangian modeling technique with predictive Bayesian capability for computing unconditional probabilities of mass as a function of space and time. The approach addresses the current need to rapidly deploy modeling capability without readily accessible information on ocean bottom currents. Contributions include (1) the development of the apparently first pollutant transport model for computing unconditional relative probabilities of pollutant location as a function of time based on limited available field data alone; (2) development of a numerical method of computing concentration profiles subject to curved, continuous or discontinuous boundary conditions; (3) development combinatorial algorithms to compute unconditional multimodal Gaussian probabilities not amenable to analytical or Markov-Chain Monte Carlo integration due to high dimensionality; and (4) the development of software modules, including a core module containing the developed Bayesian functions, a wrapping graphical user interface, a processing and operating interface, and the necessary programming components that lead to an open-source, stand-alone, executable computer application (SOSim - Sunken Oil Simulator). Extensions and refinements are recommended, including the addition of capability for accepting available information on bathymetry and maybe bottom currents as Bayesian prior information, the creation of capability of modeling continuous oil releases, and the extension to tracking of suspended oil (3-D).
82

86 Dagar 16 timmar 25 minuter : En kvantitativ innehållsanalys av nyhetsbevakningen kring oljeutsläppet i mexikanska golfen 2010 / 86 Days 16 hours 25 minutes : A quantitative content analysis of the news watch surrounding the Gulf of Mexico oil spill 2010

Ringefors, Fredrik, Andrén, Ulrika January 2011 (has links)
Purpose: When the Deepwater Horizon oilrig in the Gulf of Mexico faced disaster in late April 2010, news coverage immediately began of the disaster that would unfold. BP took the blame and its financial resources were strained as it struggled with stopping the oil leak, cleanup work as well as its PR image. While the US took many blows of the consequences to ecosystem and tourism, financial consequences swept across the world, mainly Britain, where BP had its headquarters.The event gives an excellent chance at comparing the media coverage from both the US and Britain. By studying The Daily Telegraph and The New York Times, we want to see both similarities and differences in the themes they focused on as well as seeing trends in the themes over time. Theories: The theory chapter is heavily based around the Agenda-setting theory in the media communication field. Methodology: A quantitative content analysis (QCA) of some 500 news articles in The Daily Telegraph and The New York Times from April 22 to July 15. The QCA was made to find the main theme of articles to give us data on how many articles of each theme, as well as their distribution over time. The collected data was ultimately made into diagrams. Conclusion: The two newspapers have a clear difference in that the New York Times have a more than twice the articles published compared to The Daily Telegraph. They do however both share some trends in the themes with some exceptions. Looking at the distribution of these themes within each newspaper, it’s clear that the British newspaper focused more heavily on BP while the American was focusing more heavily on consequences.
83

Valuing ecosystem services - linking ecology and policy

Noring, Maria January 2014 (has links)
Ecosystem services constitute a precondition for human welfare and survival. This concept has also become increasingly popular among both scientists and policymakers. Several initiatives have been taken to identify and value ecosystem services. Several services are threatened, and it has been concluded that in order to better manage ecosystem services they need to be further investigated and valued. By measuring them using a common metric—monetary value—they can be more easily compared and included in decision-making tools. This thesis contributes to this goal by presenting values for several ecosystem services and also including them in decision-making tools. Starting with a discussion of the concept of ecosystem services, this thesis aims to present values for certain ecosystem services and to illustrate the use of these values in systems-analysis tools such as cost-benefit analyses (CBA) and a weighting set. Links between ecology, economics and policy are discussed within a broader framework of ecosystem services. Five papers are included, in which two contingent valuation studies (CV) have been used to find values for different ecosystem services. One valuation study is focused on the effects from tributyltin (TBT) in Swedish marine waters. In addition, a quantitative assessment framework has been developed in order to simplify analysis of environmental status, progress in environmental surveillance and the relevance of different measures. It is suggested that the framework should also be used when assessing the impacts of other substances affecting the environment. The second valuation study investigates the risk of an oil spill in northern Norway. The results have been included in two CBAs and a weighting set. The first CBA compares costs for remediation of polluted sediments, caused by TBT, with the benefits of reducing TBT levels. The second CBA compares costs and benefits for reducing the probability of an oil spill. The weighting set includes monetary values on a number of impact categories where marine toxicity is based on the valuation study on TBT.  One study also examines the inclusion of environmental costs in life cycle costing (LCC) in different sectors in Sweden. Results show that respondents consider ecosystem values to be important. The values of Swedish marine waters and coastal areas outside Lofoten-Vesterålen in Norway have been identified and quantified in terms of biodiversity, habitat, recreation and scenery. In the Norwegian case, an ongoing debate on the issue of oil and gas exploration has had an impact on the number of protest bids found in the study. Based on the cost and benefits of limiting impacts on ecosystem services derived from the valuation studies, CBAs show that the suggested measures are most likely beneficial for society, and the results contribute to policy recommendations. A weighting set has been updated with new values through value transfer. The weighting set is compatible with LCA. The final study shows that companies and public organisations use environmental costs (internal and external) in a limited manner. In this thesis the ecosystem service concept is used both as an introduction and a guiding thread for the reader, as a way to frame the studies undertaken. The concept of ecosystem services can be useful, as it emphasises the importance of the services to humans. By finding and presenting values of ecosystem services, such services are more easily incorporated into decision-making. / <p>QC 20141121</p>
84

Parâmetros texturais de sedimentos para elaboração de Cartas de Sensibilidade Ambiental ao Derramamento de Óleo - Cartas SAO / Sediment Texture Parameters for Elaboration of Environmental Sensitivity Index Maps for Oil Spills. ESI maps

André Gianotti Stern 28 November 2007 (has links)
Derramamentos de petróleo geraram o aumento da atenção de órgãos governamentais e civis quanto a estudos e técnicas para minimizar os danos aos recursos ambientais e socioeconômicos causados por este tipo de acidente. O desenvolvimento de técnicas e os estudos relacionados à prevenção e resposta aos acidentes busca maior eficiência na resposta à contingência e à diminuição dos danos ambientais e socioeconômicos causados na área atingida. A Carta de Sensibilidade Ambiental ao Derramamento de Óleo (Carta SAO) é uma importante ferramenta para a diminuição de danos causados ao ambiente, para o planejamento ambiental na prevenção e na reposta a acidentes em locais de armazenamento e transporte de hidrocarbonetos, tais como dutos, ferrovias, rodovias, etc. Na Carta SAO, para áreas de exposição de sedimentos e rochas sedimentares, procura-se quantificar e qualificar uma determinada área que apresente vulnerabilidade e sensibilidade ao óleo, ou seja, estipular a área e as características intrínsecas do terreno que apresenta alguma probabilidade de ser atingido por óleo, considerando também atividades de resposta. As características dos sedimentos existentes em áreas vulneráveis permitem a determinação de sua sensibilidade, assim buscou-se estudar os parâmetros sedimentares mais influentes na determinação da sensibilidade ambiental do terreno, como a granulometria e seleção, os quais influenciam a porosidade e permeabilidade do terreno, e o cruzamento dessas informações com a declividade do terreno. A fim de testar a eficiência desses parâmetros, o estudo foi aplicado na Bacia do Ribeirão Tamanduá, na região de Cravinhos (SP), por ser interceptada pelo Duto OSBRA e a área de exposição dos arenitos da Formação Botucatu. / Oil spills have resulted in increased awareness among government and private agencies regarding studies and techniques to minimize damages caused by this type of accident to environmental and socio-economic resources. The development of techniques and the studies for prevention and response to accidents is intended to achieve greater effectiveness in dealing with this type of contingency and to decrease the environmental and socio-economic damage to the areas affected by oil spills. The Environmental Sensitivity Index Map for Oil Spills (ESI Map) is an important tool that helps to decrease the damage caused to the environment. It is also useful in planning prevention and responding to accidents in storage areas and in transporting hydrocarbons, in ducts, by rail, road, etc. The purpose of the ESI Map is to quantify and qualify certain areas of exposed sediments and sedimentary rocks that are vulnerable or present sensitivity to oil. In other words, stipulate the area and the intrinsic characteristics of the ground that may receive an oil spill, and considering the response actions. The characteristics of existing sediments in vulnerable areas allow the determination of the area\'s sensitivity. As a result, the study focused on the sedimentary parameters with greatest influence in determining the area\'s environmental sensitivity, such as granulometry and grain selection, which have an influence in the ground\'s porosity and permeability, and cross-referencing this information with the declivity of the ground. In order to test the efficiency of these parameters, the study was implemented in the Bacia do Ribeirão do Tamanduá, in the Cravinhos (SP) region, because it intercepts the OSBRA oil pipeline and an area with exposed sandstone from the Botucatu Formation.
85

The impact of an oil spill on artisanal fishermen in Baía de Guanabara and possibilities for a sustainable future

Peipke, Erica January 2006 (has links)
Brazil is a country with enormous social differences and, alongside the advancements of the industrialdevelopment and the creation of a modern society, a large part of the Brazilian population lives under fairly poor conditions, providing their subsistence by the practice of traditional knowledge; employing primitive tools and methods. One example is the sector of artisanal fishery, which at present accounts for about half of the active fishermen in Brazil (Ministério do Trabalho e Emprego, 2005). Even though these so called artisanal populations are not part of the industrialisation, they commonly suffer the consequences of the intense exploitation and unsustainable use of natural resources caused by the industrial development. The purpose of this report is to describe how the sustainability of the local artisanal fishermen population in Baía de Guanabara was affected by the oil spill at the Duque deCaxias refinery (REDUC) in January 2000. A further objective of the report is to answer how asustainable development of this population can be promoted in the future. In order to fulfil these objectives a field study was conducted in Baía de Guanabara, which included local fishermen fromfour different colonies and associations in the bay and key informants representing other stakeholders involved in the oil spill. In the report the impact of the accident on the artisanal fishermen population of Baía de Guanabara is described and several measures are discussed, which might be valuable inorder to promote a sustainable development of artisanal fishermen communities in the future. / www.ima.kth.se
86

A Temporal Analysis of a Deep-Pelagic Crustacean Assemblage (Decapoda: Caridea: Oplophoridae and Pandalidae) in the Gulf of Mexico After the Deepwater Horizon Oil Spill

Nichols, Devan 11 May 2018 (has links)
In 2010, the largest oil spill in U.S history occurred off the coast of Louisiana from April 20th to September 19th, when the well was declared officially sealed by the U.S Coast Guard, after releasing more than 4.4 million barrels of crude oil into the Gulf of Mexico (GOM) (McNutt et al., 2012). This spill was unique because it occurred in deep water approximately 1500 m below the ocean surface. Virtually nothing is known about the effects of oil spills on marine life in the deep sea, and there are limited data on mesopelagic and bathypelagic animals in the GOM before the Deepwater Horizon oil spill (DWHOS). The study presented here focuses on one of the most abundant and diverse groups of pelagic decapod crustaceans in the GOM – the family Oplophoridae and also includes one species from the family Pandalidae. Past studies on pelagic decapod crustaceans have been limited on both spatial and temporal scales. This study is unique because 1) it covers a large temporal range with data collected in 2011 and from 2015-2017, allowing for a more in-depth look at crustacean assemblage patterns, 2) it allows analysis of seasonality in reproduction, about which little is known for any deep-sea species, and 3) it assesses the potential effects of the Loop Current on species distribution and abundances, about which little is known. This information is important in understanding how the DWHOS may have affected the GOM ecosystem because pelagic decapod crustacean are intermediate components of the food web, and are in turn preyed upon by higher trophic levels. Unfortunately, there were little data on the mesopelagic ecosystem from this region before the spill, with the exception of a site in the eastern GOM (Standard Station, Hopkins et al., 1989; Hopkins et al., 1994). Therefore, these data, which incorporate samples taken one, five, six and seven years after the DWHOS, were analyzed with respect to year and season to determine if any trends were present. Results indicate that both biomass and abundance were significantly higher in 2011, than in subsequent years, indicating that the ecosystem has been declining since 2011. These two parameters were also lower in Loop Current water when compared to Common Water at all depths up to 1200 m, indicating that the Loop Current does have effects on deeper waters. The information obtained from this thesis will also act as a reference state for future studies in the GOM to monitor changes, or lack thereof, in the assemblage of deep-sea oplophorid and pandalid crustaceans.
87

Exploring the Presence of Oil Skimmers in the US: An Application of Geographic Information System for the Needs of the US Coast Guard's Marine Environmental Response.

Hoffer, Justin Eugene 07 May 2014 (has links)
No description available.
88

An Application of Geospatial Technology to Geographic Response Plans for Oil Spill Response Planning in the Western Basin of Lake Erie

Dean, David B. January 2009 (has links)
No description available.
89

The Vertical and Horizontal Distribution of Deep-Sea Crustaceans of the Order Euphausiacea (Malacostraca: Eucarida) from the northern Gulf of Mexico with notes on reproductive seasonality.

Fine, Charles Douglas 05 December 2016 (has links)
The vertical and horizontal distributions of Euphausiacea in the northern Gulf of Mexico, including the location of the Deepwater Horizon oil spill, were analyzed from 340 trawl samples collected between April-June, 2011. This study is the first comprehensive survey of euphausiid distributions from depths deeper than 1000 m in the Gulf of Mexico and included stratified sampling from five discrete depth ranges (0-200 m, 200-600 m, 600-1000 m, 1000-1200 m, and 1200-1500 m). In addition, this study encompasses the region heavily impacted by the Deepwater Horizon oil spill. Data presented here could potentially be used in ecosystem models investigating trophic effects of the spill because euphausiids are the preferred prey of a variety of higher trophic organisms. Lastly, these data represent the first quantification of euphausiid assemblages in this location after the Deepwater Horizon event and can serve as a basis of comparison against which to monitor recovery of the euphausiid assemblage after exposure to Deepwater Horizon hydrocarbons and dispersant in the water column.
90

Mapa de vulnerabilidade ambiental ao óleo e cartas SAO : trecho Praia Grande - Ilha Comprida, litoral paulista /

Romero, Ágata Fernandes. January 2009 (has links)
Conteúdo: v. 1 Texto - v. 2 Mapas / Resumo: Este trabalho apresenta Mapas de Vulnerabilidade Ambiental ao Óleo simulando um vazamento de óleo no fundeadouro do Porto de Santos, próximo ao litoral de Praia Grande. Foram também elaboradas Cartas de Sensibilidade Ambiental ao Óleo (SAO) para o trecho do litoral paulista entre os municípios de Praia Grande e Cananéia. A metodologia utilizada para elaboração das Cartas SAO é baseada nas normas do Ministério do Meio Ambiente e para a elaboração dos Mapas de Vulnerabilidade foi utilizado o modelo SIMAP, desenvolvido pela empresa ASA, capaz de representar a mancha de óleo na superfície do mar, na linha de costa e na coluna d'água. A área apresenta trechos com intenso uso turístico, principalmente nos meses de verão e áreas com ambientes naturais preservados, com destaque à presença do sistema estuarino-lagunar de Cananéia-Iguape e Unidades de Conservação, que conferem à área grande importância ecológica. As Carta SAO foram geradas nas escalas tática (1:150.000) e operacional (1:50.000 e 1:25.000) e os Mapas de Vulnerabilidade foram gerados em escalas entre 1:100.000 e 1:750.000, de forma a abranger toda a área da mancha de óleo. Os resultados confirmam a necessidade de avançar na abordagem da sensibilidade da costa ao óleo, incorporando às cartas SAO informações sobre a probabilidade das áreas serem atingidas, estimativas do tempo de contato na costa e informações sobre a área da mancha que tem potencial tóxico à biota. / Abstract: This paper shows the Environmental Vulnerability Maps a simulated oil spill in the anchorage of the Santos port, close to Praia Grande shore. ESI Maps for the São Paulo shore between the municipalities of Praia Grande and Cananéia were also built. The methodology used to build ESI Maps is based on the Ministry of the Environment rules and for the construction of the Vulnerability charts used the SIMAP model, developed by the ASA. This is capable of modeling the oil spill on the surface of the sea, in the coast line and in the water column. The whole area shows intense tourist use, especially during the summer and areas with preserved natural environments include the presence of the estuarine-lagoon system of Cananéia-Iguape and Conservation Units that give the area great ecological importance. ESI Maps were generated in the tatic range (1:150.000) and operational (1:50.000 and 1:25.000) and the vulnerability maps were generated using 1:100.000 and 1:750.000 scales, to cover the entire area of oil stain. The results confirm the sensitivity of the coast to oil, use of the information above has been incorporated in the ESI Maps to estimate shore contact lead time and of the oil spill and this toxicity potential on the environment. / Orientador: Paulina Setti Riedel / Coorientador: João Carlos Carvalho Milanelli / Banca: Eduardo Ayres Yassuda / Banca: Gabriel Henrique da Silva / Banca: Gilberto José Garcia / Banca: Iris Regina Fernandes Poffo / Doutor

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