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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.
721

Collaborative learning and the mitigation of UK ammonia emissions

Howard, Ethan January 2017 (has links)
This is a study on the conditions of collaborative learning in the context of UK ammonia emissions. By conducting an extensive review of over 40 scientific articles, this study identifies and synthesizes a list of nine conditions deemed necessary for successful collaborative learning processes and explores their extent and overall influence between three stakeholders involved in UK ammonia emissions. Hybrid focus group/key informant interviews provided the data for this exploration. This study suggests that the extent of these 9 conditions are present enough between the three stakeholders to initiate a collaborative learning process. By conducting further studies with a wider field of stakeholders, a collaborative learning process could identify possible ways to mitigate UK ammonia emissions.
722

A performance-oriented account of money awards for breach of contract

Winterton, David Michael January 2011 (has links)
It is generally accepted that the award of contract damages in English law is governed by the expectation principle. This principle provides that following an actual or anticipated breach of contract the innocent party is entitled to be put into the position that he or she would have occupied had the contract been performed. There is significant ambiguity over what ‘position’ means in this context. The conventional understanding of the expectation principle is that it stipulates the appropriate measure of loss for an award of compensation. This thesis challenges this understanding and proposes a new performance-oriented account of awards given in accordance with the expectation principle. The thesis is in two parts. Part I outlines and challenges the orthodox understanding of awards given in accordance with the expectation principle. Chapter One outlines the orthodox account, and explains the traditional interpretation of loss in this context. Chapter Two mounts a doctrinal challenge to the orthodox account, demonstrating the existence of many awards for breach of contract that do not reflect the actual loss suffered by the innocent party. Chapter Three highlights the conceptual difficulty of the orthodox account and outlines the problems with conventional terminology, proposing stable definitions for important legal concepts. Part II advances an alternative account of contract damages that draws a distinction between two different kinds of money awards. The first is an award substituting for performance. The second is an award compensating for loss. Chapter Four outlines the account’s foundations by defending the existence of the right to performance and the existence of the proposed distinction. Chapter Five explains the quantification and restriction of money awards substituting for performance. Chapter Six explains the nature of money awards compensating for loss. Finally, Chapter Seven defends English law’s preference for awarding monetary substitutes for performance rather than ordering specific performance.
723

A Data Fusion Framework for Floodplain Analysis using GIS and Remotely Sensed Data

Necsoiu, Dorel Marius 08 1900 (has links)
Throughout history floods have been part of the human experience. They are recurring phenomena that form a necessary and enduring feature of all river basin and lowland coastal systems. In an average year, they benefit millions of people who depend on them. In the more developed countries, major floods can be the largest cause of economic losses from natural disasters, and are also a major cause of disaster-related deaths in the less developed countries. Flood disaster mitigation research was conducted to determine how remotely sensed data can effectively be used to produce accurate flood plain maps (FPMs), and to identify/quantify the sources of error associated with such data. Differences were analyzed between flood maps produced by an automated remote sensing analysis tailored to the available satellite remote sensing datasets (rFPM), the 100-year flooded areas "predicted" by the Flood Insurance Rate Maps, and FPMs based on DEM and hydrological data (aFPM). Landuse/landcover was also examined to determine its influence on rFPM errors. These errors were identified and the results were integrated in a GIS to minimize landuse / landcover effects. Two substantial flood events were analyzed. These events were selected because of their similar characteristics (i.e., the existence of FIRM or Q3 data; flood data which included flood peaks, rating curves, and flood profiles; and DEM and remote sensing imagery.) Automatic feature extraction was determined to be an important component for successful flood analysis. A process network, in conjunction with domain specific information, was used to map raw remotely sensed data onto a representation that is more compatible with a GIS data model. From a practical point of view, rFPM provides a way to automatically match existing data models to the type of remote sensing data available for each event under investigation. Overall, results showed how remote sensing could contribute to the complex problem of flood management by providing an efficient way to revise the National Flood Insurance Program maps.
724

How Are American Cities Planning for Climate Change? An Evaluation of Climate Action Planning in Chicago, IL and Portland, OR

Jones, Nicolette 15 December 2012 (has links)
Contending with a changing climate presents a necessary push for planning. Although climate change is considered a global environmental problem requiring a global commitment and trans-national action, more and more, policymakers are recognizing the vital need for action at the local level. In the US, especially in the absence of national climate legislation, many local governments have begun developing strategic plans, or climate action plans (CAPs), to address adapting to impacts of climate change and mitigating greenhouse gas emissions. This thesis involves case studies of Portland, OR and Chicago, IL, cities with recently adopted CAPs and with considerable recognition in the field. The analysis involves an evaluation each city’s CAP and an evaluation of its implementation. The studies help elicit an understanding of the measures cites are employing to mitigate climate change and determine ways the planning profession can better assist communities in climate policy development and its prompt implementation.
725

The Privatization of Hazard Mitigation: A Case Study of the Creation and Implementation of a Federal Program

Jerolleman, Alessandra 06 August 2013 (has links)
This dissertation explores the role of the private and public sectors in hazard mitigation, an important part of the Federal Emergency Management Agency’s (FEMA’s) performance requirements from the Stafford Act. Hazard mitigation is the effort to reduce societal impacts from natural disasters by reducing their risk to people, property and infrastructure; before hazards occur. The goal of the work is to contribute to the literature examining the national trend towards privatization and reliance on the free market economy for the provision of government social services, through such public management movements as the “New Public Management” (NPM) of the 1980s and the general efficiency movement that encompasses a greater market orientation in public government and an increase in the use of private sector contractors as an alternative to public provision (Boston 1996). The primary question which this dissertation seeks to answer is: How has the provision of hazard mitigation services by the private sector come to be the norm and what have been the consequences. Due to the broad nature of the question and the lack of previous research, this dissertation will utilize a mixed methods approach with the goal of gaining a broad understanding of the privatization of the hazard mitigation sector in its various manifestations. The approach consists of one case study, broken down into two time periods: hazard mitigation prior to the passage of the Disaster Mitigation Act of 2000, and hazard mitigation following the Disaster Mitigation Act of 2000. The case study is based primarily upon a series of interviews and includes several imbedded cases. They will be contextualized within an overall description of hazard mitigation focusing on the history and the context of the relevant federal legislation.
726

Streamflow extremes and climate variability in Southeastern United States

Unknown Date (has links)
Trends in streamflow extremes at a regional scale linked to the possible influences of four major oceanic-atmospheric oscillations are analyzed in this study. Oscillations considered include: El Niño Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), Atlantic Multidecadal Oscillation (AMO), and North Atlantic Oscillation (NAO). The main emphasis is low flows in the South-Atlantic Gulf region of the United States. Several standard drought indices of low flow extremes during two different phases (warm/positive and cool/negative) of these oscillations are evaluated. Long-term streamflow data at 43 USGS sites in the region from the Hydro-Climatic Data Network that are least affected by anthropogenic influences are used for analysis. Results show that for ENSO, low flow indices were more likely to occur during La Niña phase; however, longer deficits were more likely during El Niño phase. Results also show that for PDO (AMO), all (most) low flow indices occur during the cool (warm) phase. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection
727

Biodiversity and Business : Multiple Case-Studies on Biodiversity Strategy in Sweden

Goaied, Amna, Sjöland, Christian January 2019 (has links)
Biodiversity loss has been stated as one of the greatest risks for the future society according to the World Economic Forum (2018, p. 5). A million species is risking extinction due to current societies’ practices according to a report published during the conduction of this study(Brondizio et al., 2019, p. 3). This situation of biodiversity has led an increasing amount of countries to enforce legislation which requires companies that work with land development to comply with no net loss goal. In Sweden, no such legislation existed with regards to biodiversity. Against this background, a group of seven companies in Sweden voluntarily chose to strive toward the goal of biodiversity net gain. According to BNG strategy, a company does not only avoid, minimise, restore and offset to reach the point where zero net loss of biodiversity is achieved, but goes farther to create a net gain. As it is not sufficient for companies to stop emissions in order to halt the loss of biodiversity, BNG practices can help mend and even reverse the negative impacts until a gain of biodiversity is attained. A greater understanding of the opportunities that companies can benefit from implementing BNG helps spread this practice across industries. No previous research within the business literature explains companies’ voluntary initiatives to embrace BNG. Therefore, this explorative study suggested the research question of what the drivers are encouraging companies to voluntarily work towards achieving biodiversity-net-gain in Sweden. Due to the lack of previous research about companies’ drivers to engage with BNG, our theoretical framework was found based on the drivers from business case for sustainability and CSR approaches as a factor to generate change. To be able to answer the research question, it was necessary to establish what BNG is and how it has developed from the concept of ecosystem services. Having an interpretivistic standpoint, this study was completed according to an inductive and deductive approach. This was in order to facilitate the exploratory nature that our qualitative and comparative study. We conducted a multiple-case study through semi-structured interviews with seven large companies in the context of Sweden. These businesses are considered as the most ambitious in working towards BNG’s goal. The findings from the primary data was complemented by secondary data about the companies, the status of current legislation in Sweden and the sustainability status in Sweden. As a result of this thesis, we found that cost and cost reduction, risk and risk reduction, sales and profit margin, reputation and brand value, attractiveness as employer, innovative capabilities, stakeholders and health and well-being of future society to all be drivers for BNG. By applying our theoretical framework in the Swedish context, the seven companies were identified to engage in a proactive corporate biodiversity behaviour. Business cases for biodiversity were identified in some of the companies.
728

Mudanças climáticas e seus impactos na produtividade da cultura de milho e estratégias de manejo para minimização de perdas em diferentes regiões brasileiras / Climate change and its impacts on maize yield and crop management strategies to minimize yield losses in different Brazilian regions

Bender, Fabiani Denise 01 August 2017 (has links)
O clima é um dos fatores ambientais que impõe os maiores riscos para a atividade agrícola, sendo responsável pelas oscilações e frustrações das safras no Brasil. Em cenário de mudanças climáticas, os atuais níveis de produtividade do milho de 1ª e de 2ª safra deverão ser alterados. Para se avaliar tais impactos, os modelos de simulação de culturas possibilitam estimar o crescimento, o desenvolvimento fenológico e a produtividade das culturas sob ampla gama de condições ambientais e de manejo, sendo, portanto, ferramentas eficientes para esse tipo de estudo. Considerando os possíveis impactos das mudanças climáticas na produtividade da cultura do milho, o presente estudo teve por objetivos: i) realizar preenchimento de falhas em séries de dados meteorológicos e, gerar séries sob projeções futuras do clima a curto (2010- 2039), médio (2040-2069) e longo (2070-2099) prazos, para os cenários de emissão intermediária (RCP4.5) e de alta emissão (RCP8.5); ii) calibrar e validar os modelos DSSAT/CERES-Maize e MONICA para simular a produtividade do milho de 1ª e de 2ª safra, e analisar a sensibilidade desses modelos, identificando os fatores de maior influência na produtividade do milho; iii) aplicar o modelo DSSAT/CERES-Maize, para determinar a produtividade do milho de 1ª e de 2ª safra, em condições de clima atual e futuro, e avaliar possíveis estratégias de manejo, de forma individual e combinada, como épocas de semeadura, ciclo da cultivar, irrigação e adubação nitrogenada, para minimização dos possíveis impactos. Para o preenchimento de falhas em séries de dados meteorológicos, o método de Bristow- Campbell (estimação da radiação solar), e a base em ponto de grade XAVIER foram as que apresentaram melhor desempenho. As projeções de clima futuro evidenciaram condições de clima mais quente, com redução no total acumulado de chuva nas regiões Norte-Nordeste e aumento no Sul do país, e as regiões Sudeste e Centro-Oeste configurando como áreas de transição. Os modelos DSSAT/CERES-Maize e MONICA apresentaram índice de desempenho (c) muito bom para ambas as safras, na estimação da produtividade do milho, com EAM inferior a 450 e 350 kg ha-1 na 1ª e na 2ª safra, respectivamente. Para as estimativas por conjunto, os valores de c foram avaliados como ótimos para as duas safras, com EAM caindo para 276 e 194 kg ha-1, na 1ª e na 2ª safra, respectivamente. Ambos os modelos mostraram sensibilidade às alterações climáticas e de adubação, porém com o modelo DSSAT/CERES-Maize se mostrando mais adequado para estudos de impactos de mudanças climáticas na cultura do milho. As simulações sob clima futuro com o modelo DSSAT/CERES-Maize, mostraram perdas de produtividade em relação aos atuais níveis, variando de 41 a 63% para milho da 1ª safra, e de 58 a 65% para o milho da 2ª safra, com as estratégias de manejo quanto a data de semeadura, ciclo da cultivar, irrigação e adubação nitrogenada mostrando redução das perdas e até mesmo ganhos de produtividade quando adotadas em condições de clima futuro. / Climate is one of the major environmental factors that impose the greatest risks for the agricultural activity, being responsible for the oscillations and frustrations of the crops in Brazil. In a scenario of climate change, the current yield levels of maize growing in-season and offseason should be impacted. In order to evaluate such impacts, crop simulation models allow estimating the growth, phenological development and yield under a wide range of environmental and crop management conditions, being efficient tools for applying to this kind of study. Considering the possible impacts of climate change on maize crop yield, the present study had as objectives: i) to fill gaps in meteorological data series and to generate series under future climate projections in the short (2010-2039), medium (2040-2069) and long (2070-2099) terms periods, for the intermediate emission (RCP4.5) and high emission (RCP8.5) scenarios; ii) to calibrate and validate the DSSAT/CERES-Maize and MONICA models to simulate inseason and off-season maize yield and to analyze the sensitivity of these models, identifying the factors that have the major influence on yield; (iii) to apply the DSSAT/CERES-Maize model to determine maize yield in the in-season and off-season, under current and future climate conditions, and evaluate possible crop management strategies, individually and in combination, such as sowing dates, crop cycle, irrigation and nitrogen fertilization, to minimize possible negative impacts. In order to fill the gaps in meteorological data series, the Bristow- Campbell method (for solar radiation estimation) and the XAVIER daily gridded database were the ones that presented the best performance. The projections of future climate showed warmer climate conditions, with a reduction in the rainfall amounts in the North-Northeast and an increase in the South of the country, with the Southeast and Center-West regions representing transition areas. Both DSSAT/CERES-Maize and MONICA models showed very good performance index (c) in the estimation of maize yield for both seasons, with MAE lower than 450 and 350 kg ha-1 during the in-season and off-season, respectively. For the ensemble estimation, the estimation improve, with optimal performance index, with MAE falling to 276 and 194 kg ha-1, for in-season and off-season maize growing, respectively. Both models showed sensitivity to climate change and fertilization, but with the DSSAT/CERES-Maize model being more suitable for studies of climate change impacts on maize crop. The simulations under future climate with DSSAT/CERES-Maize model showed a yield loss in relation to current levels, ranging from 41 to 63% for in-season, and from 58 to 65% for off-season, with management strategies regarding sowing date, cultivar cycle, irrigation and nitrogen fertilization, showing reduction of losses and even yield gains when adopted in the future climate conditions.
729

Estudo da utilização de microalgas e cianobactérias para a captura de dióxido de carbono e produção de matérias-primas de interesse industrial. / Study on the use of microalgae and cyanobacteria for the fixation of carbon dioxide and production of raw materials for industrial applications.

Cruz, Rui Vogt Alves da 08 November 2011 (has links)
O uso de microalgas e cianobactérias para a produção de biocombustíveis e outros produtos e matérias-primas de interesse comercial tem sido amplamente divulgado como uma tecnologia sustentável bastante promissora, em função das elevadas produtividades areais, potencial para fixação de CO2, uso de terras não adequadas para cultivo e possibilidade de utilizar fontes alternativas de nutrientes, tais como água salobra ou efluentes agroindustriais. A produção comercial de cianobactérias em tanques abertos em formato de pista foi estudada combinando-se a modelagem matemática do crescimento nos tanques com a avaliação técnica, econômica e de sustentabilidade do processo. Construiu-se um macromodelo para a simulação dos tanques, que permitiu determinar o impacto de variáveis ambientais como, por exemplo, temperatura e luminosidade, e otimizar condições de operação e coleta. A análise econômica detalhada demonstrou o impacto dos custos de capital, operação e consumo de energia pelo processo, também destacando a importância da receita de produtos de alto valor agregado para a viabilidade do sistema, com base na tecnologia atual. Os valores de transformidade e índices de sustentabilidade e carga ambiental, obtidos através da análise emergética, são comparáveis com outros processos para obtenção de biocombustíveis de segunda geração, mas os elevados custos de construção e operação e grande consumo de energia nas etapas de coleta e extração representam ainda grandes desafios à sua sustentabilidade. A análise de sensibilidade para as principais variáveis de processo e estudos de caso para melhorias e modelos de negócio alternativos permitiram priorizar áreas para pesquisa futura com base no impacto econômico e ambiental. / The use of microalgae and cyanobacteria for the production of biofuels and other substances of commercial interest has been widely advertised as an extremely promising sustainable technology, due to the high areal productivity, potential for fixation of CO2, possibility of using non-arable land and alternative sources of nutrients such as brackish water and agricultural and industrial effluents. The commercial production of cyanobacteria in open raceway ponds was studied through the combination of a mathematical model for the algal growth with technical, economical and sustainability evaluations. A macromodel was developed to simulate the ponds, and it was used to assess the impact of environmental variables, such as light and temperature, and to optimize the process conditions for operation and harvesting. A detailed economic analysis demonstrated the impact of capital, operation costs and energy consumption, also highlighting the importance of revenue from high value products to process viability, considering the current technology. The transformity, emergy sustainability and environmental loading indices obtained by emergy analysis are comparable to other second generation biofuels, but the high construction and operation costs and energy consumption by the harvesting and extraction steps still represent major challenges to sustainability. The sensitivity analysis and evaluation of both technology improvements and alternative business models enabled the prioritization of future research areas, based on economic and environmental impact.
730

Framework para modelagem e verificação formal de programas de controle de sistemas instrumentados de segurança. / A framework for modeling and formal verification of safety instrumented systems control programs.

Ferrarezi, Rodrigo César 09 December 2014 (has links)
Devido à alta complexidade dos Sistemas Produtivos, o projeto de sistemas de controle adequados às exigências normativas vinculadas aos processos industriais que são executados, e seu impacto no ser humano e no ambiente demandam a necessidade do desenvolvimento de soluções de controle que sejam seguras e estáveis no sentido de não causar interrupções no processo produtivo e danos ao ser humano e ao meio. Uma abordagem para o desenvolvimento de sistemas que contemplem estes requisitos baseia-se no conceito de Sistemas Instrumentados de Segurança e na aplicação das normas IEC 61508 e IEC 61511. Entretanto, assim como o desenvolvimento de qualquer software, os programas de controle de SIS também estão sujeitos a erros de especificação e projeto, mesmo quando o desenvolvimento é feito conforme os critérios normatizados. Além dos erros de projeto, também deve ser levado em consideração que as camadas de prevenção e mitigação especificadas nas normas podem ser desenvolvidas separadamente e dessa forma podem ocorrer comportamentos não previstos ou indesejáveis quando da operação conjunta delas. Uma das formas para uma melhoria na confiabilidade desses programas e que também é um requerimento pertinente ao ciclo de desenvolvimento de um SIS - de acordo com as normas de segurança IEC 61508 e IEC 61511 - é a aplicação de técnicas de verificação formal dos modelos desses programas de controle bem como o uso de um ambiente unificado para modelagem desses sistemas de controle, onde suas interações possam ser mais bem compreendidas. Atualmente, umas das técnicas mais proeminentes para a verificação de sistemas é o Model Checking, que realiza uma busca exaustiva no espaço de estados de um sistema dirigido por eventos, verificando as propriedades especificadas a partir de proposições estabelecidas em lógica temporal. Para esse trabalho é utilizada a lógica TCTL devido a sua capacidade de expressar propriedades em domínio temporal denso. Como ferramenta computacional será usado o ambiente GHENeSys, que propicia um ambiente unificado para modelagem, simulação e verificação dos sistemas por conjugar os benefícios de rede de Petri para modelagem e as técnicas de Model Checking para verificação de modelos. / Due to the high complexity of the actual Productive Systems, the design of suitable control systems according to the applicable industrial standards, and the possible negative impacts on the human being, on the environment and on equipment, the development of control solutions that are be both secure and stable as some systems have to operate nonstop is much demanded. One approach for the development systems with such requirements is the use of Safety Instrumented Systems complying with the standards IEC 61508 and IEC 61511. However, as on the development of any kind of software, SIS control programs are also prone to specification and design errors, even when the control programs are developed according to the applicable standards. Besides design errors, must be taken into consideration the fact that the SIS prevention and mitigation layers, as prescribed on the standards, can be developed individually and thus presenting unanticipated or undesirable behaviors when operating together. One way to improve the reliability of these control programs, which is also required by the safety standards IEC 61508 and IEC 61511 as part of the SIS development cycle, is the application of formal verification techniques on the control software models. Another way is to use a unified approach for modeling these control systems, and thus having the opportunity to understand their interactions better. Currently, one of the most prominent techniques for the verification of systems is the Model Checking. Such technique performs an exhaustive search in the space state of an event driven system, verifying the properties specified as established propositions in temporal logic. On this work, the TCTL logic is used due its ability to express properties in the dense time domain. As computational tool will be used GHENeSys environment, as it provides a unified environment for modeling, simulating and the verification of systems, which enjoys the benefits of modelling through Petri Nets and Model Checking techniques for formal verification.

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