Дисертації з теми "Emissions intensity"
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1
McMullan, Beth Mary. "Investment Decisions Under An Emissions Intensity Target." Thesis, Curtin University, 2020. http://hdl.handle.net/20.500.11937/79729.
Повний текст джерелаАнотація:
This thesis reports the results of a controlled laboratory experiment to test the effect of emissions price certainty on firm investments in clean technology when a regulator has set an intensity target. As fixed prices are associated with emissions closer to predictions, policymakers concerned with meeting specific targets might be more inclined to use a tax. Alternatively, if lowering emissions is a greater priority, then the market mechanism may be favoured.
2
Andres, Delgado Lidia. "Greenhouse gas emissions and energy intensity of the transport sector." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/665197.
Повний текст джерелаАнотація:
Esta tesis analiza el tema del transporte y la presión medioambiental a través de tres variables relacionadas: las emisiones, la actividad y la intensidad energética del transporte. El Capítulo 2 analiza la importancia de la población, la actividad económica, el volumen de transporte y las características estructurales de la actividad de transporte —intensidad energética del transporte, participación de los diferentes modos de transporte y participación de las diferentes fuentes energéticas— como factores explicativos de las emisiones de GEI de la actividad de transporte en la Unión Europea-28 entre 1990-2014. El análisis se basa en el modelo STIRPAT, que se amplía para investigar el impacto en las emisiones del transporte de los cambios en dicha actividad y en los del conjunto de la economía. Utilizando técnicas econométricas de datos panel, se identifica la importancia de cada factor explicativo y el impacto de su cambio en las emisiones. El Capítulo 3 estudia el impacto del sector del subsistema de transporte y almacenamiento en las emisiones de GEI de la economía mediante el análisis de subsistemas basado en el modelo input-output de Ghosh. Esta nueva metodología tiene en cuenta toda la actividad del subsistema y no solo la actividad vinculada a su demanda final. Asimismo, las emisiones totales del subsistema se descomponen en cuatro componentes explicativos: el componente escala, el componente interno neto, el componente feed-back y el componente spillover, con el objetivo de conocer las interrelaciones en términos de emisiones entre los subsectores del subsistema y entre estos y la actividad del resto de sectores de la economía. La metodología se aplica empíricamente al sector del transporte y almacenamiento en España en 2014. El Capítulo 4 examina los factores que han influido en la tendencia de la intensidad energética del transporte de mercancías por carretera español durante el período 1996-2012. Se adapta la metodología ASIF con el fin de estudiar la intensidad energética y se completa el estudio con un análisis de descomposición LMDI. Además, el cambio en la intensidad energética se analiza cuantificando la contribución de cada mercancía transportada a través de la metodología de la atribución de cambios en los índices Divisia.
Los tres capítulos principales de esta tesis ofrecen varias contribuciones. El Capítulo 2 desarrolla metodológicamente el modelo STIRPAT al aplicar al estudio de las emisiones del transporte la participación de los diferentes modos de transporte y la participación de las diferentes fuentes de energía. En segundo lugar, contribuye a analizar empíricamente las emisiones de GEI del sector del transporte en la Unión Europea en el período 1990-2014. En tercer lugar, evalúa la efectividad potencial de las acciones promovidas en el Libro Blanco del Transporte de 2011. El Capítulo 3 desarrolla metodológicamente el modelo de subsistemas input-output desde la perspectiva de la oferta y este se amplía con el fin de estudiar el impacto medioambiental de sustancias contaminantes. En segundo lugar, ofrece una contribución empírica, ya que aplica el modelo al análisis de los efectos de la actividad del sector de transporte y almacenamiento en las emisiones de GEI de la economía en España en 2014. Finalmente, el Capítulo 4 adapta la metodología ASIF a fin de investigar la intensidad energética del transporte de mercancías por carretera y amplía el análisis mediante la descomposición LMDI. En segundo lugar, identifica el grado en que cada mercancía contribuye al cambio en la intensidad energética a través de la metodología de la atribución de cambios en los índices Divisia. En tercer lugar, investiga empíricamente la intensidad energética del transporte español de mercancías por carretera en el período 1996-2012.This dissertation analyses the topic of transport and environmental pressure through three closely related issues —transport GHG emissions, transport activity, and transport energy intensity. Chapter 2 analyses the importance of population, economic activity, transport volume, and structural characteristics of transport activity —in terms of transport energy intensity, of transport modes' share, and of energy sources’ mix— as driving factors of GHG emissions in transport activity in the European Union over the period 1990–2014. The analysis is based on the STIRPAT model, which is broadened to investigate in depth the impact on transport emissions of changes in the transport activity and in the whole economy. Using panel data econometric techniques, the significance of each factor and the impact of its change on emissions are identified. Chapter 3 studies the impact of the transport and storage subsystem sector on GHG emissions of the whole economy by using input–output subsystems analysis based on the Ghosh model. This new methodology that is developed in the chapter takes into account the whole activity of the subsystem and not only the activity linked to its final demand. Additionally, in the aim of learning the interrelations in terms of emissions between the subsectors of the subsystem and between them and the activity of the rest of the sectors of the economy, total emissions of the subsystem are decomposed into four explanatory components. These are scale component, net own internal component, feed-back component, and spillover component. The methodology is applied to the Spanish transportation and storage sector in 2014. Chapter 4 examines the factors that have influenced the energy intensity trend of the Spanish road freight transport of heavy goods vehicles over the period 1996–2012. The ASIF methodology is adapted to study it, and the chapter uses multiplicative LMDI decomposition analysis. Additionally, the change in energy intensity is analyzed in more depth by quantifying the role of each commodity transported using the methodology of the attribution of changes in Divisia indices. The three main chapters of this dissertation offer various contributions. Chapter 2 develops methodologically the STIRPAT model since it adds as driving factors of transport emissions the modal share and the energy consumption mix. Second, it empirically contributes to analyze the GHG emissions of the transport sector in the European Union in the period 1990–2014. Third, it evaluates the potential effectiveness of the actions promoted in the 2011 Transport White Paper. Chapter 3 develops methodologically an input–output subsystems model from the supply perspective and expands it in order to study the environmental impact of polluting substances. Second, it offers an empirical contribution, as it applies the preceding model with the purpose of studying the effects of the activity of the transportation and storage sector on GHG emissions of the whole economy in Spain in 2014. Finally, Chapter 4 adapts the ASIF methodology to energy intensity in the road freight transport and enhances it by applying decomposition analysis. Second, it identifies the degree to which each transported commodity has contributed to the change in energy intensity through the methodology of attribution of changes in Divisia indices. Four, it provides an empirical contribution through the analysis of energy intensity of Spanish road freight transport of heavy goods vehicles over the period 1996–2012.
3
Haukland, Eirik. "Trade and Environment: Emissions intensity of Norway's imports and exports." Thesis, Norwegian University of Science and Technology, Industrial Ecology Programme, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1416.
Повний текст джерелаАнотація:
An Environmental Input-Output Analysis (EIOA) have been performed in order to assess the importance of including foreign emission and economic data when estimating emissions attached to imports. The CO2, SOx and NOx emissions induced by total imports are calculated using both foreign and domestic inventory. The results show significantly higher emissions when using foreign data, especially for SOx.
Demand-specific emission intensities are established for both import and domestic production. A comparison of those for emissions of CO2, SOx and NOx indicates much higher values for the imports than for the domestic production.
In addition, analyses are conducted on a more detailed level, defined by the NACE-industry aggregation. Foreign inventory are used on the imports, and domestic inventory are used on the domestic production. The detailed demand-specific emission intensities show similar trends compared with the total results mentioned above. However, there are considerable differences between some of the NACE sectors.
Finally, a brief overview of the assumed emissions related to household consumption is performed. However, the analysis are not on such a detailed level that conclusions can be made.
4
Arvidsson, Martins Mikael. "Convergence of CO2 emissions in the Americas." Thesis, Jönköping University, IHH, Nationalekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-53137.
Повний текст джерелаАнотація:
Maintaining global warming to 2 degrees Celsius above pre-industrial levels is vital. Whether the convergence hypothesis holds for carbon dioxide emissions is important for policymakers facing this issue. This paper investigates the convergence behavior of carbon dioxide emissions for 39 countries in the Americas from 1960-2016. A linear regression test of convergence which looks for conditional sigma convergence is employed, and a clustering algorithm is used to identify convergence clubs. The results show evidence of convergence in the region for the long run. Convergence clubs are identified for the short run. The convergence clubs show some relation to spatial distribution and income level. Possible factors determining the formation of convergence clubs are investigated through logistic regression. Initial level of emissions and energy intensity were found to have the largest impact determining what convergence club a country belongs to. Per capita GDP, trade openness, and renewable energy were all found to be highly significant factors determining what convergence club a country belongs to as well. Different results were found for urbanization’s impact in determining the formation of convergence clubs. These findings show that policymakers should promote allocation schemes for carbon dioxide emissions. Policymakers should also aim to reduce carbon footprint based on the economy’s structural characteristics.
5
Ekman, Oskar. "Dynamic pricing and carbon intensity in demand response functions." Thesis, Linköpings universitet, Energisystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-109633.
Повний текст джерелаАнотація:
The European power sector is facing significant challenges related to investments in grid infrastructure and generation capacity. The continued deployment of intermittent renewables also puts pressure on current grid conditions. Smart grids is seen as a cost-efficient way to overcome these challenges through a more efficient use of current capacity. Demand response is a corner-stone in smart grid development, and is implemented to introduce flexibility on the demand side. Most demand response programs have used dynamic pricing to incentivize consumers to shift consumption from peak to off-peak hours. In Stockholm Royal Seaport, where a sustainable energy system is envisioned, it has been proposed that dynamic pricing should be complemented with an indicator depicting carbon intensity of purchased electricity. This indicator is based on average emissions, which is one of two fundamental perspectives on assessing environmental impacts of electricity consumption. The aim of this study was to evaluate whether the approach used to quantify carbon intensity in Stockholm Royal Seaport is appropriate in the context of demand response. To achieve this, a literature review has been conducted regarding potential benefits of demand response, power system dynamics and carbon dioxide allocation methods. A quantitative analysis has also been conducted, where the signal proposed for Stockholm Royal Seaport has been modeled under different timeframes. The results show that the CO2-signal in Stockholm Royal Seaport is constructed in such a way that it is largely affected by hydro generation, which in turn makes it correlate negatively with price. As a result, the CO2-signal would counteract many of the predicted long-term benefits of demand response. Furthermore it seems unlikely that the signal would result in significant short-term emission reductions, since hydro generally is used to balance supply and demand in the Swedish and Nordic systems. Based on the literature review, it was concluded that marginal emissions would be a more appropriate environmental indicator than average emissions. However, it remains a difficulty to construct a day-ahead control signal based on this perspective because of system complexity and lack of data. Historical marginal carbon intensity was nevertheless modeled in this study using a linear regression model. The results indicate that price itself might be a sufficient indicator of marginal emissions. Finally, a model for a signal based on prognoses of intermittent renewable generation is proposed, where the rationale is that consumers should decrease consumption during hours of low renewable generation. This signal was modeled using data on renewable generation from Denmark since corresponding data in Sweden is not yet available. Results show that it would be possible to construct a rather accurate control signal in this way. There are also reasons to believe that demand response based on this type of signal would result in long-term environmental benefits.Den europeiska energisektorn står inför stora utmaningar, bland annat i form av investeringsbehov i nätinfrastruktur och produktionskapacitet för att säkra framtida leveranssäkerhet. Den fortsatta utbyggnaden av intermittent förnybar kraftproduktion ställer också nya krav på nätet och på aktörernas flexibilitet. Smarta nät ses som ett kostnadseffektivt sätt för att övervinna dessa utmaningar genom en mer effektiv användning av nuvarande kapacitet. En viktig del i detta är efterfrågerespons, som syftar till att minska belastningen på nätet under höglasttimmar genom att i högre grad än tidigare involvera konsumenten. De flesta initiativ inom efterfrågerespons har använt dynamisk prissättning för att uppmuntra konsumenter att flytta konsumtion från höglast- till låglasttimmar. I Norra Djurgårdsstaden, där visionen är att bygga ett hållbart och mer flexibelt energisystem, har det föreslagits att dynamisk prissättning bör kompletteras med en indikator som visar den inköpta elens koldioxidintensitet. Denna indikator är baserad på medelel, vilket är ett av två fundamentala sätt att miljövärdera el. Syftet med denna studie var att utvärdera om den metod som används för att kvantifiera koldioxidintensiteten i Norra Djurgårdsstaden är lämplig i samband med efterfrågerespons. För att uppnå detta har en litteraturstudie genomförts gällande potentiella fördelar med efterfrågerespons, hur kraftsystemet fungerar samt olika metoder för att miljövärdera el. En kvantitativ analys har också genomförts, där CO2-signalen i Norra Djurgårdsstaden har modellerats utifrån olika tidsperspektiv. Resultaten visar att CO2-signalen i Norra Djurgårdsstaden är konstruerad på ett sådant sätt att den till stor del påverkas av vattenkraftens produktionsvariationer, vilket i sin tur gör att signalen generellt rör sig i motsatt riktning mot prissignalen. Resultatet av detta är att CO2-signalen motverkar många av de långsiktiga fördelarna med efterfrågestyrning. Dessutom ter det sig osannolikt att signalen skulle leda till signifikanta utsläppsminskningar på kort sikt, eftersom lasten i Sverige främst balanseras av variationer i vattenkraft. Utifrån litteraturstudien kan man dra slutsatsen att marginalelens koldioxidintensitet skulle vara en lämpligare miljöindikator än genomsnittliga utsläpp i samband med efterfrågestyrning. Det är dock svårt att i praktiken konstruera en styrsignal baserat på detta perspektiv på grund av systemets komplexitet och brist på data. Historiska marginella utsläpp modellerades emellertid med hjälp av linjär regression. Resultaten från detta indikerade att priset kan vara en tillräcklig indikator även för variationerna i koldioxidintensitet utifrån ett marginalperspektiv. Slutligen föreslås en modell för en signal baserad på dagenföreprognoser om intermittent förnybar produktion, där budskapet skulle vara att användaren minskar sin konsumtion under timmar med låg förnybar produktion. Denna signal modellerades med hjälp av uppgifter om förnybar produktion från Danmark eftersom motsvarande uppgifter om Svensk produktion inte finns tillgängliga ännu. Resultaten visar att det skulle vara möjligt att konstruera en relativt träffsäker styrsignal på detta sätt. Det finns också skäl att tro att efterfrågerespons baserat på denna typ av signal skulle leda till miljömässiga fördelar på längre sikt.
6
Reniers, Jorn. "Analysis of a real-time signal for greenhouse gas emissions of district heating consumption." Thesis, KTH, Industriell ekologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169508.
Повний текст джерелаАнотація:
The district heating system (DHS) of Stockholm is one of the largest systems in the world with a total yearly production of 10TWh of heat and 2TWh of electricity (through combined heat and power plants). Large amounts of greenhouse gasses (GHG) are emitted to produce this heat and electricity. Given the goal of the City of Stockholm to reduce the amount of GHG emissions to 3 ton per capita in 2015 and to keep reducing emissions at a similar rate after 2015, it is important to identify the potentials for further reductions. Numerous studies have been done on how the DHS can become more sustainable by installing new generation units. However, also the consumers have an influence on the DHS. After all, it are the consumers who decide when and how much heat or electricity they use. Most former studies and environmental guidelines for the DHS in Stockholm focussed on the producer side. This thesis looks at the consumer perspective of the (heat of the) district heating system. A real-time signal giving the greenhouse gas emissions of individual households is developed and its potential and challenges are discussed. With this signal, households that want to minimise their environmental impact have a tool to decrease their environmental impact by changing their consumption. This can be a first step to transform the DHS to a smart district heating system. First, generic models to calculate the dynamic greenhouse gas intensity of the heat production of district heating and to calculate the greenhouse gas emissions related to the heat consumption of households are suggested. Then the feedback signal with those real-time household emissions is calculated for representative households in Stockholm based on data of Stockholm’s DHS and data about hot tap water consumption in Sweden. Results indicate that variations in household level greenhouse gas emissions mostly reflect changes in consumption but can also result from changes by the producer. Intraday variations are mostly caused by changes in hot tap water consumption, while variations on a timescale of a few days are caused by changes in heating consumption (changing weather) and changes made by the producer (to use different fuels). Then several scenarios are calculated, each scenario looking at the actions a consumer can take to shift or reduce his/her consumption (decrease hot tap water usage, lower indoor temperature etc.). The real-time household emissions are calculated again to see if the signal gives the needed incentives (is the household rewarded for its effort? Does it get further incentives?). It was found that a strong time-incentive (to decrease consumption when it saves most emissions) is missing if the average perspective is used to calculate the emission intensity of the heat production. Also, the results confirmed the finding that the feedback signal might not reflect changes in consumption. Finally, challenges for the signal are discussed. One of the major hurdles is the fact that household consumption of heat (heating and hot tap water) can often not be measured on a household level. Thus, it has to be estimated but it seems very difficult to get this estimation accurate enough to give correct feedback to households, especially about the emissions saved by their efforts to reduce/shift their consumption. Secondly, the time resolution should be chosen well to still get accurate results but not make the signal to data-intensive. Finally, the result is heavily dependent on the chosen methodology (average or marginal perspective? Do you account for the electrical side of the DHS? How about the distribution losses? Etc.).
7
Zaidi, Syed Haider Ali. "Modelling and forecasting energy intensity, energy efficiency and CO₂ emissions for Pakistan." Thesis, University of Leicester, 2017. http://hdl.handle.net/2381/39346.
Повний текст джерелаАнотація:
The aim of this thesis is to examine the significant environmental issues, especially, Green House Gases (GHGs) emissions and specifically Carbon Dioxide (CO₂) emissions which are mainly caused by energy use. This thesis consists of three core chapters. Chapters 2 and 4 discuss how to stabilize and forecast CO₂ emissions for Pakistan while chapter 3 discusses the energy efficiency of Asian developing countries. Exogenous Technical Change (TC) and endogenous TC models are considered in the chapter 2 for the stabilization of CO₂ emissions. Specifically, the estimated results show that endogenous TC model (which is estimated by following the Kalman Filter (KF) technique) does a better job in comparison. The results also point out the existence of a trade-off between GDP growth and fuel prices. Inter-fuel substitutions are estimated using the Almost Ideal Demand System (AID). Results suggest that stabilization can be achieved just in short run but it needs too much time for the implementation in the long run plans. In chapter 3, a parametric Stochastic Frontier model Approach (SFA) is used for a panel of 19 countries including Pakistan over the period of 1980 to 2013. The individual and relative energy efficiency over time of all counties is estimated. The focus is to find either energy intensity a good indicator of energy efficiency or not. According to the estimated results, energy intensity is not a good indicator of energy efficiency but the energy efficiency estimated using SFA after controlling for some of the economic factors (fuel prices, population, income, etc.) it is. In chapter 4, the relationship between CO₂ emissions and income, and energy consumption and income are found to support the Environmental Kuznets Curve (EKC) hypothesis. Univariate (Grey Prediction Model (GM), Exponential Smoothing (ES), Holt-Winter (H-W)) and multivariate model solving techniques are used to predict CO₂ emissions and their forecasting abilities are compared. A new technique, Out Of Sample Grey Prediction (OOSGP), is introduced after providing a critique of the GP model to get better forecast results. The findings of this study provide a valuable reference with which Pakistan’s government could formulate measures to reduce CO₂ emissions by curbing the unnecessary consumption of energy.
8
Moutinho, Victor Manuel Ferreira. "Essays on the determinants of energy related CO2 emissions." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/15156.
Повний текст джерелаАнотація:
Doutoramento em Sistemas Energéticos e Alterações ClimáticasOverall, amongst the most mentioned factors for Greenhouse Gases (GHG) growth are the economic growth and the energy demand growth. To assess the determinants GHG emissions, this thesis proposed and developed a new analysis which links the emissions intensity to its main driving factors. In the first essay, we used the 'complete decomposition' technique to examine CO2 emissions intensity and its components, considering 36 economic sectors and the 1996-2009 periods in Portugal. The industry (in particular 5 industrial sectors) is contributing largely to the effects of variation of CO2 emissions intensity. We concluded, among others, the emissions intensity reacts more significantly to shocks in the weight of fossil fuels in total energy consumption compared to shocks in other variables. In the second essay, we conducted an analysis for 16 industrial sectors (Group A) and for the group of the 5 most polluting manufacturing sectors (Group B) based on the convergence examination for emissions intensity and its main drivers, as well as on an econometric analysis. We concluded that there is sigma convergence for all the effects with exception to the fossil fuel intensity, while gamma convergence was verified for all the effects, with exception of CO2 emissions by fossil fuel and fossil fuel intensity in Group B. From the econometric approach we concluded that the considered variables have a significant importance in explaining CO2 emissions and CO2 emissions intensity. In the third essay, the Tourism Industry in Portugal over 1996-2009 period was examined, specifically two groups of subsectors that affect the impacts on CO2 emissions intensity. The generalized variance decomposition and the impulse response functions pointed to sectors that affect tourism more directly, i. e. a bidirectional causality between the intensity of emissions and energy intensity. The effect of intensity of emissions is positive on energy intensity, and the effect of energy intensity on emissions intensity is negative. The percentage of fossil fuels used reacts positively to the economic structure and to carbon intensity, i. e., the more the economic importance of the sector, the more it uses fossil fuels, and when it raises its carbon intensity, in the future the use of fossil fuel may rise. On the other hand, positive shocks on energy intensity tend to reduce the percentage of fossil fuels used. In fourth essay, we conducted an analysis to identify the effects that contribute to the intensity of GHG emissions (EI) in agriculture as well as their development. With that aim, we used the 'complete decomposition' technique in the 1995-2008 periods, for a set of European countries. It is shown that the use of Nitrogen per cultivated area is an important factor of emissions and in those countries where labour productivity increases (the inverse of average labour productivity in agriculture decreases), emissions intensity tends to decrease. These results imply that the way to reduce emissions in agriculture would be to provide better training of agricultural workers to increase their productivity, which would lead to a less need for energy and use of Nitrogen. The purpose of the last essay is to examine the long and short-run causality of the share of renewable sources on the environmental relation CO2 per KWh electricity generation- real GDP for 20 European countries over the 2001-2010 periods. It is important to analyze how the percentage of renewable energy used for electricity production affects the relationship between economic growth and emissions from this sector. The study of these relationships is important from the point of view of environmental and energy policy as it gives us information on the costs in terms of economic growth, on the application of restrictive levels of emissions and also on the effects of the policies concerning the use of renewable energy in the electricity sector (see for instance European Commission Directive 2001/77/EC, [4]). For that purpose, in this study we use Cointegration Analysis on the set of cross-country panel data between CO2 emissions from electricity generation (CO2 kWh), economic growth (GDP) and the share of renewable energy for 20 European countries. We estimated the long–run equilibrium to validate the EKC with a new approach specification. Additionally, we have implemented the Innovative Accounting Approach (IAA) that includes Forecast Error Variance Decomposition and Impulse Response Functions (IRFs), applied to those variables. This can allow us, for example, to know (i) how CO2 kWh responds to an impulse in GDP and (ii) how CO2 kWh responds to an impulse in the share of renewable sources. The contributions of this thesis to the energy-related CO2 emissions at sectorial level are threefold: First, it provides a new econometric decomposition approach for analysing and developing CO2 emissions in collaboration with science societies that can serve as a starting point for future research approaches. Second, it presents a hybrid energy-economy mathematic and econometric model which relates CO2 emissions in Portugal based on economic theory. Third, it contributes to explain the change of CO2 emissions in important economic sectors in Europe, in particular in Portugal, taking normative considerations into account more openly and explicitly, with political implications at energy-environment level within the European commitment.
De uma forma geral, entre os fatores mais apontados para o crescimento das emissões de Gases de Efeito de Estufa (GEE), estão o crescimento económico e o crescimento das necessidades energéticas. Para identificar os determinantes das emissões de GEE, esta dissertação propôs e desenvolveu uma nova análise que liga a intensidade das emissões aos seus principais responsáveis. No primeiro ensaio, foi utilizada a técnica da ‘decomposição total’ para examinar a intensidade das emissões de CO2 e os seus componentes, considerando 36 setores económicos e o período entre 1996-2009 em Portugal. A indústria (em particular cinco setores industriais) contribui fortemente para os efeitos da variação da intensidade de CO2. Conclui-se, entre outros, que a intensidade das emissões reage mais significativamente a choques no peso dos combustíveis fósseis no consumo total da energia, comparativamente a choques em outras variáveis. No segundo ensaio, conduziu-se uma análise para 16 sectores industriais (Grupo A) e para o grupo dos cinco setores industriais mais poluentes (Grupo B), baseada no estudo da convergência para a intensidade das emissões e para os seus principais determinantes, bem como numa análise econométrica. Concluiu-se que existe convergência sigma para todos os efeitos, à exceção da intensidade dos combustíveis fósseis, enquanto a convergência gama se verificou para todos os efeitos com a exceção das emissões de CO2 por combustível fóssil e intensidade de combustível fóssil, no Grupo B. A partir da abordagem econométrica, concluiu-se que as variáveis consideradas têm uma importância significativa na explicação da intensidade das emissões de CO2. No terceiro ensaio foi analisada a indústria do turismo em Portugal durante o período de 1996-2009, em particular para dois grupos de subsetores que afetam a intensidade das emissões de CO2. A decomposição generalizada de variância e as funções de impulso-resposta apontaram uma causalidade bidirecional entre intensidade de emissões e intensidade de energia para setores que afetam o turismo mais diretamente. O efeito da intensidade de emissões é positivo na intensidade da energia e o efeito da intensidade da energia na intensidade das emissões é negativo. A percentagem de combustíveis fósseis utilizados reage positivamente à estrutura económica e à intensidade do carbono, isto é, quando um setor ganha importância económica, tende a usar mais combustível fóssil e quando aumenta a intensidade do carbono, no futuro, o uso de combustíveis fósseis pode aumentar. Por outro lado, choques positivos na intensidade de energia tendem a reduzir a percentagem de combustíveis fósseis utilizados. O objectivo do quarto ensaio é identificar os efeitos que contribuem para a intensidade dos gases de estufa na agricultura, bem como a sua evolução, Para isso, utilizou-se a técnica de ‘decomposição total’ no período 1995-2008 para um grupo de países europeus. Ficou demonstrado que o uso de nitrogénio por área cultivada é um fator importante nas emissões e naqueles países cuja produtividade do trabalho aumenta, a intensidade das emissões tende a aumentar. O resultado implica que o caminho para reduzir as emissões na agricultura pode passar por uma melhor formação dos trabalhadores ligados à agricultura para melhorar a sua produtividade, o que pode conduzir a uma menor necessidade e uso de nitrogénio. O objectivo do último ensaio é examinar a causalidade de longo e curto prazo da quota de fontes renováveis na relação ambiental entre o desenvolvimento económico (PIB) e as emissões de CO2 por KWh de eletricidade produzida num conjunto de 20 países Europeus no período de 2001-2010. Esta nova abordagem sugere que a quota de fontes renováveis na produção de eletricidade é um determinante importante para explicar as diferenças na relação Rendimento-emissões de CO2 por Kwh nos países Europeus e que as evidências empíricas suportam a relação ambiental da curva de Kuznets. As contribuições desta dissertação para os assuntos relacionados com as emissões de CO2 a um nível setorial são as seguintes: primeiro, oferece uma nova abordagem econométrica da decomposição para analisar a evolução das emissões de CO2 que pode servir como um ponto de partida para futuras investigações. Segundo, apresenta uma abordagem híbrida, juntando a matemática e a economia de energia e um modelo econométrico para relacionar as emissões de CO2 na Europa e, em particular, em Portugal com base em teorias económicas. Terceiro, contribui para explicar as mudanças nas emissões de CO2 em setores económicos importantes para Portugal, conjugando considerações normativas aberta e explicitamente, com implicações políticas no comprometimento europeu, ao nível energético-ambiental.
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Lueken, Roger Alan. "Reducing Carbon Intensity in Restructured Markets: Challenges and Potential Solutions." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/479.
Повний текст джерелаАнотація:
The U.S. electric power sector is in the early stages of transitioning from a reliance on carbon intensive generation sources to a system based on low-carbon sources. In this thesis, I present analyses of four different aspects of this transition, with an emphasis on the PJM Interconnection. The effects of bulk electricity storage on the PJM market I analyze the value of three storage technologies in the PJM day-ahead energy market, using a reduced-form unit commitment model with 2010 data. I find that large-scale storage would increase overall social welfare in PJM. However, the annualized capital costs of storage would exceed social welfare gains. Consumers would save up to $4 billion annually, largely at the expense of generator surplus. Storage modestly increases emissions of CO2 and other pollutants. The external costs and benefits of wind energy in PJM Large deployments of wind create external costs and benefits that are not fully captured in power purchase agreements. I find that wind’s external costs in the PJM market are uncertain but significant when compared to levelized PPA prices. Pollution reduction benefits are very uncertain but exceed external costs with high probability. The climate and health effects of a USA switch from coal to gas electricity generation I analyze the emission benefits created by a hypothetical scenario in which all U.S. coal plants are switched to natural gas plants in 2016. The net effect on warming is unclear; results are highly sensitive to the rate of fugitive methane emissions and the efficiency of replacement gas plants. However, the human health benefits of such a switch are substantial. The costs of building and operating new gas plants likely exceed the health benefits. Robust resource adequacy planning in the face of coal retirements Over the next decade, many U.S. coal-fired power plants are expected to retire, posing a challenge to system planners. I investigate the resource adequacy requirements of the PJM Interconnection, and how procuring less capacity may affect reliability. I find that PJM’s 2010 reserve margin of 20.5% was sufficient to achieve the stated reliability standard with 90% confidence. PJM could reduce reserve margins to 13% and still achieve levels of reliability accepted by other power systems.
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Moro, Alberto, and Laura Lonza. "Electricity carbon intensity in European Member States: Impacts on GHG emissions of electric vehicles." Elsevier, 2017. https://publish.fid-move.qucosa.de/id/qucosa%3A73241.
Повний текст джерелаАнотація:
The Well-To-Wheels (WTW) methodology is widely used for policy making in the transportation sector. In this paper updated WTW calculations are provided, relying on 2013 statistic data, for the carbon intensity (CI) of the European electricity mix; detail is provided for electricity consumed in each EU Member State (MS). An interesting aspect presented is the calculation of the GHG content of electricity traded between Countries, affecting the carbon intensity of the electricity consumed at national level. The amount and CI of imported electricity is a key aspect: a Country importing electricity from another Country with a lower CI of electricity will lower, after the trade, its electricity CI, while importing electricity from a Country with a higher CI will raise the CI of the importing Country. In average, the CI of electricity used in EU at low voltage in 2013 was 447 gCO2eq/kWh, which is the 17% less compared to 2009. Then, some examples of calculation of GHG emissions from the use of electric vehicles (EVs) compared to internal combustion engine vehicles are provided. The use of EVs instead of gasoline vehicles can save (about 60% of) GHG in all or in most of the EU MSs, depending on the estimated consumption of EVs. Compared with diesel, EVs show average GHG savings of around 50% and not savings at all in some EU MS.
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Zhang, Wenquan. "Understanding Energy and Carbon Intensities in China: Trends, Projections, and Uncertainties." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-177097.
Повний текст джерелаАнотація:
Two weeks before the Copenhagen summit on climate change, China officially made a pledge to cut its carbon intensity by 40 to 45 percent below 2005 level by 2020. The thesis has tried to look into the quality and quantity concern of this pledge made by the biggest CO2 emitter in the world. From the existing projections on China’s business as usual (BAU) scenarios to 2020, there are no unanimous conclusions showing whether there is additionality in China’s pledge to reduce 40-45% of its carbon intensity between 2005 and 2020. Further analysis on selected results, we have found scenarios of two frequently cited authorities, namely IEA and EIA are, to some extent, misinterpreted regarding their references/current policies scenarios. On the other hand, several more typical BAU scenarios, like Garnaut’s and ReMIND-R, predicted much lower than 40% reduction rate in the period of 2005-2020. China’s pledge seems achievable with certain extra effort, comparing with historical pathways of several OECD countries, including U.S., Japan, Germany, and Korea. The average period in these four countries to go through China’s abatement path is around 21 years. From a global prospect, China’s pledge is impressive but not enough to address the climate change issue. The biggest uncertainty inherited in the pledge is the uncertain peak year of absolute emissions. The critical movement beyond 2020 pledge is to peak its absolute CO2 emissions as early as possible. Such a challenging target shall be set as no later than 2030 according to our overviews on the related literature.
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Hanson, Lundström Elenor. "Kuznets in Sweden? : A study of the relationship between carbon dioxide emissions and income." Thesis, Jönköping University, JIBS, Economics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-7879.
Повний текст джерелаАнотація:
According to the Environmental Kuznets Curve (EKC), economic growth will eventually cause carbon dioxide emissions to decrease. Is this the case in Sweden? A time series covering the period 1800-1995 is used to analyze the relation between carbon dioxide emissions and income per capita in Sweden. The empirical results indicate that an EKC for carbon dioxide is highly likely to exist in Sweden for the examined period. To take the analysis further, a cross-section data set is employed to examine the relationship between carbon dioxide emissions, income per capita and 4 other potentially influential variables in 75 countries. Only carbon intensity of energy is significant for carbon dioxide emissions. This implies that the utilized energy source is of importance, and it is crucial to separate energy consumption from carbon dioxide emissions. Emissions is a matter of structural aspects such as the type of industry and production a country comprise, and what type of energy that is consumed; not merely the quantity of energy. Sweden has experienced a shift in production techniques and in energy supply, and the energy-efficiency has improved during the past 100 years. It is consequently plausible to believe that it is not a critical income per capita which decreases CO
2 emissions – it is the “right” energy sources, energy efficiency and improved technology.
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Agerhäll, Isabella, Malin Kindmark, and Cecilia Stern. "Towards Climate Neutral Facility Management : Improved Greenhouse Gas Emission Calculations for Ihus." Thesis, Uppsala universitet, Institutionen för samhällsbyggnad och industriell teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413768.
Повний текст джерелаАнотація:
Uppsala municipality has set a goal in line with the UN’s 2030 Agenda for sustainable development to be fossil-free by 2030. To achieve this a lot of local companies have signed the Uppsala Climate Protocol. One of these companies is the municipal facility management company AB Uppsala Kommun Industrihus, Ihus. This project aimed to help Ihus map their emissions connected to facility maintenance and management and to enable them to reach their goal of becoming climate neutral by 2030. The daily facility management was split up into the categories gardening, ventilation and installation, cleaning and facility work, materials and products, renovations, and painting. A sustainability spend analysis was performed on Ihus’ organisation and emissions per spent MSEK were calculated for each category by researching Ihus’ suppliers. By using those emission intensities, the two categories with the highest emissions could be identified as renovations and materials and products with intensities of 84.48 and 57.56 tonnes CO2e/MSEK, respectively. The remaining categories all had intensities below 3 tonnes CO2e/MSEK. Sensitivity analyses were performed on the results by tweaking the values of which the emissions were based on. The results showed that to lessen Ihus’ climate impact the areas of improvement are life cycle assessments for their facilities and overseeing transports.
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Chung, Whan-Sam. "Structural Analysis of Socio-Technical Impacts on Energy Use and Related Greenhouse Gas Emissions in Korea Based on Energy Input-Output Tables." Kyoto University, 2014. http://hdl.handle.net/2433/185184.
Повний текст джерела
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Weigel, Brent Anthony. "Development of a commercial building/site evaluation framework for minimizing energy consumption and greenhouse gas emissions of transportation and building systems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44735.
Повний текст джерелаАнотація:
In urbanized areas, building and transportation systems generally comprise the majority of greenhouse gas (GHG) emissions and energy consumption. Realization of global environmental sustainability depends upon efficiency improvements of building and transportation systems in the built environment. The selection of efficient buildings and locations can help to improve the efficient utilization of transportation and building systems. Green building design and rating frameworks provide some guidance and incentive for the development of more efficient building and transportation systems. However, current frameworks are based primarily on prescriptive, component standards, rather than performance-based, whole-building evaluations. This research develops a commercial building/site evaluation framework for the minimization of GHG emissions and energy consumption of transportation and building systems through building/site selection.
The framework examines, under uncertainty, multiple dimensions of building/site operation efficiencies: transportation access to/from a building site; heating, ventilation, air conditioning, and domestic hot water; interior and exterior lighting; occupant conveyances; and energy supply. With respect to transportation systems, the framework leverages regional travel demand model data to estimate the activity associated with home-based work and non-home-based work trips. A Monte Carlo simulation approach is used to quantify the dispersion in the estimated trip distances, travel times, and mode choice. The travel activity estimates are linked with a variety of existing calculation resources for quantifying energy consumption and GHG emissions. With respect to building systems, the framework utilizes a building energy simulation approach to estimate energy consumption and GHG emissions. The building system calculation procedures include a sensitivity analysis and Monte Carlo analysis to account for the impacts of input parameter uncertainty on estimated building performance. The framework incorporates a life cycle approach to performance evaluation, thereby incorporating functional units of building/site performance (e.g energy use intensity).
The evaluation framework is applied to four case studies of commercial office development in the Atlanta, GA metropolitan region that represent a potential range of building/site alternatives for a 100-employee firm in an urbanized area. The research results indicate that whole-building energy and GHG emissions are sensitive to building/site location, and that site-related transportation is the major determinant of performance. The framework and findings may be used to support the development of quantitative performance evaluations for building/site selection in green building rating systems and other efficiency incentive programs designed to encourage more efficient utilization and development of the built environment.
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Irffi, Guilherme Diniz. "Essays on the relationship between co2 emission and income global." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10159.
Повний текст джерелаАнотація:
Banco do Nordeste do BrasilThe company apparently always ignored (or did not spend enough attention) externalities of economic activity harmful to the environment and, consequently, is facing its possible effects in recent decades. Recently, now more conscious of their actions, their continued growth policies are usually formulated taking into account the growth the trade-off between economic growth and environmental preservation cluttered, given that "the agenda" is to combine increased income with sustainability and environmental preservation. Thus, this thesis investigated the relationship between CO2 emissions and economic activity, considering an overall look from the second half of the twentieth century. However, it is used as a motto the literature of economic growth by considering that the relationship above can be analyzed from the Environmental Kuznets Curve, the estimation of the trend of CO2 emission intensity and the analysis of convergence Emission CO2pc. According to the results achieved by three chapters, one can say that to reduce the level of CO2 emissions and mitigate the effects of global warming we need to establish a new regime of CO2 emission quotas with more countries than what has been agreed with the PQ and still contemplate developing countries like China, Ãndia, MÃxico and Ãfrica do Sul At the same time, we must establish a system of taxation for GHG emissions in order to achieve the desired goals of stabilizing and subsequently reduce the emission levels more easily. Moreover, it is necessary that quotas and taxation of CO2 emissions are set from the current level of emissions and the speed of convergence for clubs highest emission level. However, there must be differentiated quotas schemes for the rich countries and developing countries, so allow them to reach the income levels of rich countries. The differentiated regime is necessary because the effects of global warming on society in the XXI century and elevations are consequences of the gas atmosphere during the eighteenth and nineteenth centuries. Therefore, it is for developed countries to further reduce CO2 emissions, according to their historical emissions. However, less developed nations can not fail to participate in this system and also is a need to reconcile economic growth with environmental preservation in such a way to mitigate the effects of global warming on future generations. Another measure that tends to be efficient in combating global warming is to support the development of alternative energy sources with low emission intensity, so increasing the speed of convergence for economies with low GHG emissions. That is, we must achieve energy efficiency from the use of clean energy (less carbon-intensive) and, for that necessarily need to replace fossil fuels. Moreover, it is necessary to transfer technologies with low carbon emissions of developed countries to developing nations in order to generate a global welfare, since this measure tends to increase speed of convergence to a low- CO2 emissions.
As sociedades aparentemente sempre ignoraram (ou nÃo despenderam atenÃÃo suficiente) as externalidades da atividade econÃmica danosas ao meio ambiente e, como consequÃncia, vem enfrentando seus possÃveis efeitos nas Ãltimas dÃcadas. Recentemente, agora mais consciente de suas aÃÃes, suas polÃticas de continuidade do crescimento sÃo geralmente formuladas levando-se em consideraÃÃo o crescimento o trade-off entre crescimento econÃmico desordenado e preservaÃÃo ambiental, haja vista que âa ordem do diaâ à conciliar aumento da renda com sustentabilidade como a preservaÃÃo do meio ambiente. Neste sentido, esta Tese investigou a relaÃÃo entre as emissÃes de CO2 e a atividade econÃmica, considerando um aspecto global a partir da segunda metade do sÃculo XX. No entanto, utiliza-se como mote a literatura de crescimento econÃmico por considerar que a relaÃÃo supracitada pode ser analisada a partir da Curva de Kuznets Ambiental, da estimaÃÃo da tendÃncia da Intensidade de EmissÃo de CO2 e da anÃlise de ConvergÃncia de EmissÃo de CO2 per capita (CO2pc). De acordo com os resultados alcanÃados pelos trÃs capÃtulos, pode-se dizer que para reduzir o nÃvel de emissÃo de CO2 e mitigar os efeitos do aquecimento global à preciso estabelecer um novo regime de cotas emissÃo de CO2 com mais paÃses do que o que foi acordado com o Protocolo de Quioto e, ainda, contemplar os paÃses em desenvolvimento como China, Ãndia, MÃxico e Ãfrica do Sul. Ao mesmo tempo, à preciso estabelecer um sistema de tributaÃÃo para as emissÃes de gases de efeito estufa (GEE), a fim de permitir alcanÃar os objetivos de estabilizar e, posteriormente, reduzir os nÃveis de emissÃo de maneira mais fÃcil. AlÃm disso, à preciso que as cotas e a tributaÃÃo de emissÃo de CO2 sejam definidas a partir do nÃvel atual de emissÃo e da velocidade de convergÃncia para clubes de maior nÃvel de emissÃo. No entanto, deve haver regimes de cotas diferenciadas para os paÃses ricos e os paÃses em desenvolvimento, de tal maneira a permitir que estes alcancem os nÃveis de renda dos paÃses ricos. O regime diferenciado se faz necessÃrio porque os efeitos do aquecimento global sobre a sociedade nos sÃculo XX e XXI sÃo consequÃncias dos gases alÃados a atmosfera terrestre durante os sÃculos XVIII e XIX. Por isso, cabe aos paÃses desenvolvidos a maior reduÃÃo das emissÃes de CO2, em funÃÃo do seu histÃrico de emissÃo. Todavia, as naÃÃes menos desenvolvidas nÃo podem deixar de participar deste sistema e, ainda, à necessÃrio conciliar crescimento econÃmico com preservaÃÃo ambiental de tal forma a mitigar os efeitos do aquecimento global sobre as futuras geraÃÃes. Outra medida que tende a ser eficiente ao combate do aquecimento global à subsidiar o desenvolvimento de fontes alternativas de energia com baixa intensidade de emissÃo, de tal modo a aumentar a velocidade de convergÃncia para economias de baixa emissÃo de GEE. Ou seja, à preciso alcanÃar a eficiÃncia energÃtica a partir do consumo de energia limpa (menos intensiva em emissÃo de carbono) e, para isto, necessariamente, à preciso substituir os combustÃveis fÃsseis. AlÃm do mais, se faz necessÃrio a transferÃncia de tecnologias com baixa emissÃo de carbono dos paÃses desenvolvidos para as naÃÃes em desenvolvimento a fim de gerar um bem-estar global, uma vez que esta medida tende a aumentar velocidade de convergÃncia para uma economia de baixa emissÃo de CO2.
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Song, Jaemin. "Emission trading with absolute and intensity caps." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/85796.
Повний текст джерелаАнотація:
Thesis: S.M., Massachusetts Institute of Technology, Technology and Policy Program, 2005.Cataloged from PDF version of thesis.
Includes bibliographical references (page 66).
The Kyoto Protocol introduced emission trading to help reduce the cost of compliances for the Annex B countries that have absolute caps. However, we need to expand the emission trading to cover developing countries in order to achieve the maximum benefits from both higher environment quality and lower abatement cost. In this sense, the emission trading scheme at a global level in the future needs to consider the inclusion of countries with intensity caps as well as with absolute caps, since many countries, including developing countries and the United States, are interested in intensity caps. In this thesis, we aim to address the issue of two different emission cap-setting methods, absolute and intensity caps, under international emission trading; How would the changes in BAU emission levels and GDP affect the market-clearing price, total cost, and costs for the affected countries? What would be the differences in the price and costs when a country with an intensity cap is the trading partner instead of one with an absolute cap? A two-country mathematical model is developed to answer these questions. The model analysis shows that there are complex interactions among the elasticities of price and costs in response to the changes in emissions and GDP of the affected countries. For the same emission size countries, the BAU condition changes of a country have greater impacts on the own cost changes than the changes of the trading partner do. For the different size emission countries, the relative size of emissions of the countries is the key factor to determine the total cost and its distribution to each country. The changes of the bigger emission country tend to dominate the trading system in terms of price and costs. Generally, we can conclude that selection of proper caps should be made considering the relative size of emissions and commitment levels of the affected countries, their marginal coefficients and own characteristics of correlation between GDP and emissions.
by Jaemin Song.
S.M.
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Wei, Honghong. "Essays in energy, environmental and health economics." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/202081/1/Honghong_Wei_Thesis.pdf.
Повний текст джерелаАнотація:
This thesis comprises of three essays that explore issues related to energy economics, environmental economics and health economics. The first essay discusses the monetary policy response to commodity price shocks in the U.S., Canada and Mexico in the presence of NAFTA. The second essay investigates the relationship between carbon emissions and urbanization in different sectors across economies. The third essay studies the theoretical and empirical relationship between inequality aversion and public health expenditures. The common thread running through these essays is the use of cross-country analysis for deriving evidence-informed insights of relevance to policies in these domains.
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Khalid, Ashiq Hussain. "Development of phosphor thermometry systems for use in development gas turbine engines." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/development-of-phosphor-thermometry-systems-for-use-in-development-gas-turbine-engines(f01316f9-4622-4a6d-b2d0-611a9191b5eb).html.
Повний текст джерелаАнотація:
The pursuit for improved engine efficiency is driving the demand for accurate temperature measurement inside turbine engines. Accurate measurement can allow engines to be operated closer to their design limits to improve thermal efficiency. It can enable engineers to verify mechanical integrity, provide better prediction of component life, validate CFD and other design tools and aid the development for leaner more efficient engines. Unfortunately, experimentally measuring surface temperatures under harsh rotating conditions is challenging. This EngD study conducted by Ashiq Hussain Khalid at the University of Manchester and Rolls-Royce plc, reviews the rationale of using phosphor thermometry over existing methods, including thermocouples, pyrometry and thermal paints/melts, which lack detail, accuracy, or are too expensive for continuous testing. Although phosphor thermometry exhibits desirable characteristics, the high temperature and fast rotating engine environment presents some challenges that would need to be addressed before a successful measurement system can be implemented. Examples of such issues include: rising blackbody radiation, restricted optical access, fibre optic constraints and limited time period to collect data. These factors will impose measurement limits and greatly influence the design philosophy of the system, including phosphor choice, phosphor lifetime characteristics, bonding technique, excitation/detection methodologies and probe design. Taking these into consideration, the research focuses on the development of phosphor thermometry systems for use in development gas turbine engines, with measurement solutions for specific engine components. The high pressure turbine blade was given research priority. A number of phosphors including YAG:Tb, YAG:Tm. Y2O3:Eu and Mg3F2GeO4:Mn were investigated and characterised in terms of intensity and lifetime decay, with increasing temperature up to 1500oC. Spectral analysis and absolute intensity measurements established emission peaks and permitted comparative quantitative analysis to optimise system setup. The intensity of phosphor emission relative to Planck's blackbody radiation was also performed. YAG:Tm under 355nm illumination was found to exhibit the highest emission intensity at high temperatures, and because its spectral emission peak at 458nm was the lowest, its advantage in terms of blackbody radiation was further amplified. For rotating components, an upper temperature limit is reached based on the emission intensity at rising blackbody radiation levels and the system's ability to detect fast decays. A lower limit is reached based on the quenching temperature, probe design and rotational velocity. There are different methods to correct the distorted decay waveform as it traverses through the acceptance cone of the fibre. A phosphor selection criterion, taking into consideration these limitations, was successfully applied for various rotating engine components. The optical layout was setup and tested on stationary and rotating cases under laboratory conditions using similar design constraints, including fibre choice, maximum permissible lens size and target distances. A series of tests validated design methodologies and assumptions to enable testing on full scale rotating engine components. Mg3F2GeO4:Mn, using 355nm illumination, was found to be the most suitable phosphor for the HP drive cone. The estimated performance under the expected rotational speeds was found to be 624-812°C with a standard uncertainty of ±0.99%. YAG:Tm, illuminated with 355nm, was found to be the most promising phosphor for high pressure turbine blade measurements. The performance under the expected rotational speeds was found to be 1117-1375°C with a standard uncertainty of ±0.97%. This is better than other competing technologies that are currently available for temperature measurement of rotating turbine blades.
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Harper, Stuart Edward. "Single-dish intensity mapping with the QUIJOTE MFI and GBT." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/singledish-intensity-mapping-with-the-quijote-mfi-and-gbt(3bb4234f-46b7-4191-aec0-408345be1d97).html.
Повний текст джерелаАнотація:
Today, there are only a limited number of surveys of the sky at 1 to 20 GHz. These frequencies lie below the all-sky surveys of WMAP and Planck, but are critical in constraining the spectral slope of Galactic synchrotron emission. Knowledge of the large-scale spectral morphology of Galactic synchrotron emission is critical in the understanding of the interstellar medium and the weak signal from the polarised cosmic microwave background. Recently, ground based observations from S-PASS, C-BASS and the QUIJOTE Multifrequency Instrument (MFI) have been populating these missing frequencies. This thesis presents the first QUIJOTE MFI maps of the Northern sky in total intensity at 11, 13, 17 and 19 GHz, and the first single-dish mapping observations of Lynds dark cloud, LDN1622 at 5 and 13.7GHz. The observations from both instruments are used to probe the nature of spinning dust emission on degree and arcminute scales within the Galaxy. A full data reduction and calibration pipeline for QUIJOTE MFI time-ordered-data is described. The absolute flux density scale uncertainty of the MFI data is between 2 and 3 per cent. The pipeline characterises key properties of the MFI, such as the RFI sources, beams, bandpasses, 1/f noise and more. A key part of the pipeline was the development of an MPI ready Destriping map-maker and a maximum-likelihood map-maker. The map-making code can be applied to a range of different single-dish instruments and is used to reduce both the QUIJOTE MFI wide-survey maps of the Northern sky, and the GBT arcminute resolution raster observations of LDN 1622. A detailed discussion is given on the simulations used to test the integrity of the map-making implementation. Parametric model fitting to the SEDs of four spinning dust emission regions is performed. The MFI wide-survey maps are used in conjunction with existing multifrequency 1degree survey data. The addition of MFI maps is used to confirm the previously tentative spinning dust emission source LDN 1582/84. The mean peak frequency of spinning dust emission over the four spinning dust sources is found to be ⟨νsp⟩ = 27.2 +/- 0.7 GHz, and the mean ratio of the peak spinning dust brightness over the dust optical depth is ⟨Asp/τ250⟩ = 1.24 +/- 0.18 × 104 Jy/τ250. Spectral index maps are derived from the MFI wide-survey data in combination with 408 MHz and WMAP 23 GHz data. These maps are used to further quantify the ubiquity of spinning dust emission throughout the Galaxy. The results show that the median flux density spectral index within the inner Galactic disk for |b| < 2° is 0.24 +/- 0.07. This implies that at 23 GHz, spinning dust emission contributes 25 +/- 5 per cent of the total integrated emission within the inner disk of the Galaxy.
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Sue, Wing Ian, A. Denny Ellerman, and Jaemin Song. "Absolute vs. Intensity Limits for CO2 Emission Control: Performance Under Uncertainty." MIT Joint Program on the Science and Policy of Global Change, 2006. http://hdl.handle.net/1721.1/31204.
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We elucidate the differences between absolute and intensity-based limits of CO2 emission when there is uncertainty about the future. We demonstrate that the two limits are identical under certainty, and rigorously establish their relative attractiveness under two criteria: preservation of expectations—the minimization of the difference between the actual level and the initial expectation of abatement associated with a one-shot emission target, and temporal stability—the minimization of the variance of abatement due to fluctuations in emissions and GDP over time. Empirical tests of these theoretical propositions indicate that intensity caps are preferable for a broad range of emission reduction commitments. This finding is robust for developing countries, but is more equivocal for developed economies.Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).
ISW was supported by U.S. Department of Energy Office of Science (BER) Grant No. DE-FG02-02ER63484. ADE and JMS were supported by the MIT Joint Program on the Science and Policy of Global Change, funded through a government-industry partnership including U.S. Department of Energy Office of Science (BER) Grant No. DE-FG02-94ER61937, U.S. Environmental Protection Agency Cooperative Agreement No. XA-83042801-0, and a group of corporate sponsors from the U.S. and other countries.
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Yu, Chao. "An acoustic intensity-based method and its aeroacoustic applications." Diss., Connect to online resource - MSU authorized users, 2008.
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Gerlinger, Katrin. "Muster globaler anthropogener CO₂-Emissionen : sozio-ökonomische Determinanten und ihre Wirkung." Phd thesis, Universität Potsdam, 2004. http://opus.kobv.de/ubp/volltexte/2005/166/.
Повний текст джерелаАнотація:
Die wesentlichen sozio-ökonomischen Prozesse, die die vermehrten anthropogenen CO₂-Emissionen verursachen, können durch die Determinanten Bevölkerung, Wohlstand (Bruttoinlandsprodukt pro Kopf) und Technologie (Energie- und Kohlenstoffintensität) vereinfacht beschrieben werden. Der Einfluss dieser Determinanten auf die Emissionsänderungen ist nicht für alle Länder der Erde gleich.Zeitreihen der CO₂-Emissionen aus der Verbrennung fossiler Energieträger, der Bevölkerung, des Bruttoinlandsproduktes und des Primärenergieverbrauches von 121 Ländern bilden die Grundlage für das entwickelte statistische Verfahren zur schrittweisen Informationsverdichtung, mit dem der gesamte Datenraum zu 6 energiewirtschaftlichen Ländertypen schrittweise zusammengefasst wird.
Zur Beschreibung dieser Ländertypen wird mit Hilfe der Dekompositionsanalyse der Einfluss der Bevölkerungs-, der Wohlstands- und der Technologiekomponenten an den Emissionsänderungen quantifiziert. Die Ländertypen können vereinfacht als Repräsentanten unterschiedlicher Entwicklungsstufen und -richtungen angesehen werden. Sie bilden unter anderem eine Grundlage für die Weiterentwicklung und Kalibrierung regionalisierter makro-ökonomischer Modelle zu den sozio-ökonomischen Hintergründen der vermehrten anthropogenen CO₂-Emissionen.
The principal socio-economic processes that cause the increased anthropogenic emissions of carbon dioxide can be modeled by the variables population, affluence (gross domestic product per capita) and technology (energy intensity and carbon intensity). The impact of these variables on the changes of the CO₂ emissions is not the same for all countries of the earth.
Time series of carbon dioxide emissions from burning of fossil energies, population, gross domestic product and of primary energy supply of 121 countries were analyzed. A statistical method for the stepwise aggregation of these data into six classes of countries according to their energy use profile.
The impact of population, affluence and technology components on the changes of the emissions of carbon dioxide is quantified by decomposition analysis. The classes of countries according to their energy use profile can be regarded as representative of different states and of different paths of development. These classes are also a basis for the elaboration and calibration of regionalized macro economic models to analyze the socio economic determinants of the increased anthropogenic emissions of carbon dioxide.
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Kluge, Regine, Lidia Chavdarova, Martha Hoffmann, Carsten Kobe, Bogdan Malkowski, Françoise Montravers, Lars Kurch, et al. "Inter-reader reliability of early FDG-PET/CT response assessment using the Deauville Scale after 2 cycles of intensive chemotherapy (OEPA) in Hodgkin’s Lymphoma." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-204087.
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Purpose: The five point Deauville (D) scale is widely used to assess interim PET metabolic response to chemotherapy in Hodgkin lymphoma (HL) patients. An International Validation Study reported good concordance among reviewers in ABVD treated advanced stage HL patients for the binary discrimination between score D1,2,3 and score D4,5. Inter-reader reliability of the whole scale is not well characterised. Methods: Five international expert readers scored 100 interim PET/CT scans from paediatric HL patients. Scans were acquired in 51 European hospitals after two courses of OEPA chemotherapy
(according to the EuroNet-PHL-C1 study). Images were interpreted in direct comparison with staging PET/CTs. Results: The probability that two random readers concord on the five point D score of a random case
is only 42% (global kappa = 0.24). Aggregating to a three point scale D1,2 vs. D3 vs. D4,5 improves concordance to 60% (kappa = 0.34). Concordance if one of two readers assigns a given score is 70% for score D1,2 only 36% for score D3 and 64% for D4,5. Concordance
for the binary decisions D1,2 vs. D3,4,5 is 67% and 86% for D1,2,3 vs D4,5 (kappa = 0.36 resp. 0.56). If one reader assigns D1,2,3 concordance probability is 92%, but only 64% if D4,5 is called. Discrepancies occur mainly in mediastinum, neck and skeleton. Conclusion: Inter-reader reliability of the five point D-scale is poor in this interobserver analysis of paediatric patients who underwent OEPA. Inter-reader variability is maximal in cases assigned to D2 or D3. The binary distinction D1,2,3 versus D4,5 is the most reliable criterion for clinical decision making.
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Griffin, Paul. "Radical change in energy intensive UK industry." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665430.
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Managing energy demand is essential to energy security and climate change mitigation. The industrial sector accounts for over a fifth of UK primary energy demand and greenhouse gas emissions. Energy intensive industry is uniquely restricted in the way it uses energy and emits greenhouse gasses. In this thesis, the potential of radical measures to achieve significant energy demand reduction and emissions abatement in UK energy intensive industry is assessed. Adopted is a multidisciplinary approach combining thermodynamic and techno-economic analysis techniques. Bottom-up assessments are applied to key energy intensive sectors of industry to capture the diverse and interactive array of technological characteristics invisible from a top-down perspective. Detailed projection models are built to design and analyse technology roadmaps for the sectors out to 2050. In an illustrative roadmap assessment, the technological pathways of radical process transition and carbon sequestration were each shown to achieve about 80% abatement in 2050 from 1990 emissions levels. Radical process transition achieved greater abatement before 2030 and this was reflected in lower cumulative emissions over the full period. Higher risk is associated with carbon sequestration from its reliance on timely access to CO2 transport and storage technology to compensate for lower short-medium term abatement. Although, combining carbon sequestration with high levels of biomass combustion indicated the largest potential abatement to 2050. Abatement economics in the iron and steel sector are notably sensitive to resource costs and the carbon trading price. The carbon trading price influences relative production costs in favour of higher abating pathways, but increases absolute costs. This signals the need for supportive policy measures that accelerate technology development and deployment while mitigating the risk of the carbon trading price to competitiveness. Some carbon capture technologies reduce relative production cost even in the absence of a carbon price, but this excludes the cost of CO2 transport and storage. Meanwhile, radical process transition pathways have a higher dependence on the future prices of natural gas, electricity, and scrap. Future work should focus on expanding the economic appraisal to other sectors and to indirect costs, as well as incorporating wider material efficiency strategies and running different future scenarios.
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Lau, Yiu Hon. "Application of joint intensity algorithms to the registration of emission topography and anatomical images /." Electronic version, 2004. http://adt.lib.uts.edu.au/public/adt-NTSM20040901.094913/index.html.
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Alfredsson, Eva. "Green consumption energy use and carbon dioxide emission." Doctoral thesis, Umeå universitet, Kulturgeografi, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-80.
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The aim of this thesis is to explore the quantitative potential to reduce energy requirements and CO2 emissions through changed patterns of consumption, given unchanged levels of consumption expenditure. The thesis question is analysed using a systems analysis approach which in this case means that life cycle assessment data on energy requirements and CO2 emissions related to household consumption are combined with a financial and behavioural analysis to make sure that the budget constraint is kept and that both the first and second order effects of adopting a green consumption pattern are analysed. The budget constraints are kept using a general linear model. By using marginal propensities to spend to direct the reallocation of saved or deficit money calculated utility is maintained as far as possible. Further, investigations explore the impact of individual household demographic characteristics and geographic context on household consumption patterns, energy requirements and CO2 emissions. The key result of this thesis is that changed household behaviour, choosing “green“ products and energy efficient technology will not make a big difference. What can be achieved in the short time perspective by adopting an almost completely green consumption pattern and energy efficient technology is a reduction of energy requirements by around 8% and CO2 emissions by around 13%. With a longer time perspective and further technological change that provides additional possibilities to move consumption patterns in a greener direction, the effect on energy requirements and CO2 emissions is still fairly small. By 2020, the potential to reduce energy requirements is around 13% and CO2 emissions around 25%. In the most extreme scenario (2050), the scope for reducing energy requirements is 17% and for CO2 emissions 30%. All these reductions will be outpaced by growth in income almost as soon as they are implemented. Of policy relevance the results reveal that very limited impact can be expected by a policy relying on greener consumption patterns, whether adopted voluntarily or as a result of incentives such as tax changes. Such a policy cannot achieve more than a small and temporary reduction to growth in energy requirements and CO2 emissions. It is also shown that, prescribing specific consumption patterns as a means of reducing energy requirements and CO2 emissions has to be done with care. This is illustrated by one of the experiments in which adopting a partly green consumption pattern, a green diet, in fact increased total energy requirements and CO2 emissions. This, and the results of all the other experiments show the importance of applying a systems approach. It demonstrates that life cycle data alone are irrelevant for assessing the total effects of adopting green consumption patterns. Further research on the potential to reduce energy requirements and CO2 emissions thus primarily needs to better capture system wide effects rather than to improve on, and fine tune the measurement of the energy requirements and CO2 emissions related to individual products.
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Deutsch, Kerry Ann. "Behavior of the atomic oxygen 5577 Ångström emission intensity at mid-latitudes : a climatological view /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/6803.
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Tajudeen, Ibrahim. "Essays on energy efficiency and fuel subsidy reforms." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/essays-on-energy-efficiency-and-fuel-subsidy-reforms(3066138a-809f-4a4f-aeaf-a1e5f6087891).html.
Повний текст джерелаАнотація:
This thesis uses innovative approaches to analyse energy policy interventions aimed at enhancing the environmental sustainability of energy use as well as its consequential welfare implications. First, we examine the relationship between energy efficiency improvement and CO2 emissions at the macro level. We use the Index Decomposition Analysis to derive energy efficiency by separating out the impact of shifts in economic activity on energy intensity. We then employ econometric models to relate energy efficiency and CO2 emissions accounting for non-economic factors such as consumers lifestyle and attitudes. The applications for 13 OPEC and 30 OECD countries show that at the country-group and individual country level, increase in energy intensity for OPEC is associated with both deteriorations in energy efficiency and shifts towards energy-intensive activities. The model results suggest that the reduction in energy efficiency in general go in tandem with substantial increases in CO2 emissions. The decline in energy intensity for OECD can be attributed mainly to improvements in energy efficiency which is found to compensate for the impact on CO2 emissions of income changes. The results confirm the empirical relevance of energy efficiency improvements for the mitigation of CO2 emissions. The method developed in this chapter further enables the separate assessment of non-economic behavioural factors which according to the results exert a non-trivial influence on CO2 emissions. Secondly, having empirically confirmed the relationship between energy efficiency improvements and CO2 emission at the macro level in Chapter 2, we investigate potential underlying drivers of energy efficiency improvements taking into account potential asymmetric effects of energy price change in Chapter 3. This is crucial for designing effective and efficient policy measures that can promote energy efficiency. In addition to the Index Decomposition Analysis used to estimate the economy-wide energy efficiency in Chapter 2, we also use Stochastic Frontier Analysis and Data Envelop Analysis as alternative methods. The driving factors are examined using static and dynamic panel model methods that account for both observed and unobserved country heterogeneity. The application for 32 OECD countries shows that none of the three methods leads to correspondence in term of ranking between energy efficiency estimates and energy intensity at the country level corroborating the criticism that energy intensity is a poor proxy for energy efficiency. The panel-data regression results using the results of the three methods show similarities in the impacts of the determinants on the energy efficiency levels. Also, we find insignificant evidence of asymmetric effects of total energy price but there is proof of asymmetry using energy specific prices. Thirdly, in Chapter 4 we offer an improved understanding of the impacts to expect of abolishing fuel price subsidy on fuel consumption, and also of the welfare and distributional impacts at the household level. We develop a two-step approach for this purpose. Key aspect of the first step is a two-stage budgeting model to estimate various fuel types elasticities using micro-data. Relying on these estimates and the information on households expenditure shares for different commodities, the second step estimates the welfare (direct and indirect) and distributional impacts. The application for Nigeria emphasises the relevance of this approach. We find heterogeneous elasticities of fuel demand among household groups. The distributional impact of abolishing the kerosene subsidy shows a regressive welfare loss. Although we find a progressive loss for petrol, the loss gap between the low- and high-income groups is small relative to the loss gap from stopping kerosene subsidy, making the low-income groups to suffer a higher total welfare loss. Finally, from the highlighted results, we draw the following concluding remarks in chapter 5. Energy efficiency appears a key option to mitigate CO2 emissions but there is also a need for additional policies aiming for behavioural change; energy specific prices and allowing for asymmetry in analysing the changes in energy efficiency is more appropriate and informative in formulating reliable energy policies; the hypothesis that only the rich would be worse-off from fuel subsidy removal is rejected and the results further suggest that timing of the fuel subsidy removal would be crucial as a higher international oil price will lead to higher deregulated fuel price and consequently, larger welfare loss.
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Zlateva, Yana. "Investigation of Cherenkov emission with applications in dosimetry, image guidance and intensity modulation in radiation therapy." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121558.
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The aims of this work are to validate the potential application of Cherenkov emission (CE) in radiotherapy dosimetry, online imaging and beam modulation by analysis of its correlation with radiation dose and by a spectral shift to the near-infrared (NIR) window of biological tissue in order to maximize its detection. This work makes an original contribution to scientific knowledge by effectively correlating radiation dose and CE in two dimensions, using an optical fiber and grating spectrometer, without need for a computer-generated spatially variant conversion factor or a fluorescent dye, and by successfully shifting CE to the NIR in a tissue-simulating phantom with the use of quantum dots (QDs).Radiation dose was correlated with CE via both computer simulation and experimental measurements using clinical 6-18 MeV electron beams. A Monte Carlo (MC) CE simulator was designed using the Geant4 simulation toolkit. In order to maximize the signal, beam incidence angle was optimized through simulation and experiment and the feasibility of two-fiber detection was assessed. Phantoms used in the experiments were a water tank and a tissue-simulating phantom composed of water, Intralipid® and beef blood. The optical detection system consisted of a multi-mode step-index fiber optic cable (numerical aperture = 0.22 for dose versus Cherenkov studies), positioned out of the beam and connected to a single-channel diffraction grating spectrometer incorporating a front- or back-illuminated charge-coupled device (CCD). A cylindrical ionization chamber was used for dose measurements. CdSe/ZnS core-shell QDs, emitting at (650 ± 10) nm, were used to achieve a NIR shift of the CE signal.A preliminary software analysis indicated a strong correlation between radiation dose and CE with a Pearson correlation coefficient larger than 0.99. A beam incidence angle of 50° relative to the surface normal produced a CE maximum along the horizontal fiber. An angle of 47° (corresponding to more than 80% of the maximum signal) was adopted in order to maximize the scan depth by avoiding beam perturbation due to setup components and fiber protrusion into the field. Dose versus CE correlation was investigated via water phantom ion chamber scans along the beam central axis and optical fiber scans with the fiber tip positioned at the field edge. With all data sets normalized to 1, the effective point of measurement of the optical system for 18, 12 and 6 MeV clinical electron beams was found to be at depths of approximately 1.7, 0.8, and 0.1 cm, respectively, downstream from the fiber axis, with a Pearson correlation coefficient for all (simulated and experimental) data larger than 0.99. CE by an 18 MeV electron beam was successfully shifted towards 650 nm in water and in a tissue-simulating phantom. Smaller field sizes and larger QD depths resulted in a lower signal, though a shift was still apparent for a 1 cm depth of the QDs. Statistical data analysis indicated no noise bias and that radiation might have impacted the spectrometer electronics.The results of this work validate the potential for application of CE in radiotherapy dosimetry, online imaging and intensity modulation based on tumor microenvironment information, such as oxygenation, since CE is intrinsic to the beam, non-ionizing and can be detected outside the beam, and the QDs used for the experiments are photostable, tunable, and can be modified to incorporate molecular reporters. Future work involves the use of a multi-channel spectrometer for simultaneous collection of main, reference and background signals, incorporation of a lens or a single-mode fiber to reduce the sensitive volume, as well as development of better spectral data extraction techniques. It is expected that the proposed technique will be applicable to 3D dose mapping by means of diffuse optical tomography, online CE imaging and localization during radiotherapy, and beam modulation based on tumor microenvironment information.Les objectifs de cette étude sont de valider la potentielle application de l'émission Cherenkov (EC) pour la dosimétrie en radiothérapie, pour l'imagerie en temps réel et pour la modulation des faisceaux par l'analyse de sa corrélation avec la dose de rayonnement et par un décalage spectral vers la fenêtre infrarouge proche (FIP) des tissus biologiques afin de maximiser sa détection. Ce travail apporte une contribution originale aux travaux antérieurs en corrélant efficacement, d'une part, la dose de rayonnement et l'EC en 2 dimensions à l'aide d'une fibre optique et d'un spectromètre à réseau, et ce, sans l'aide d'un facteur de conversion variant spatialement et généré par ordinateur ou d'un colorant fluorescent, et d'autre part, en effectuant avec succès le déplacement de l'EC à la FIP dans un fantôme simulant les tissus biologiques grâce à l'utilisation de points quantiques (PQs).La dose de rayonnement a été corrélée avec l'EC à la fois par simulation informatique et par mesures expérimentales. Un simulateur Monte Carlo (MC) de l'EC a été conçu en utilisant la plateforme de simulation Geant4. Les fantômes utilisés dans les expériences consistaient d'un réservoir d'eau et d'un fantôme simulant les tissus biologiques composés d'eau, d'Intralipid® et de sang de boeuf. Le système de détection optique est composé d'un câble de fibre optique multi-mode à saut d'indice, placé hors du faisceau d'électron et relié à un spectromètre à réseau de diffraction à canal unique comprenant un dispositif à couplage de charge éclairé par l'avant ou l'arrière. Des points quantiques CdSe/ZnS, émettant à (650 ± 10) nm, ont été utilisés afin de réaliser un décalage de l'EC vers la FIP.Une analyse préliminaire a indiqué une forte corrélation entre la dose de rayonnement et de l'EC avec un coefficient de corrélation de Pearson supérieur à 0.99. La corrélation de la dose en fonction de l'EC a été étudiée via des scans de la chambre d'ionisation dans le fantôme d'eau le long de l'axe central du faisceau ainsi que par des scans de fibre optique avec la pointe de la fibre positionnée sur le bord du champ du faisceau. Après normalisation, le point effectif de mesure du système optique des faisceaux d'électrons cliniques de 18, 12 et 6 MeV, s'est révélé être situé à des profondeurs respectives de 1.7 cm, 0.8 cm et 0.1 cm, et ce, en aval de l'axe de la fibre, avec un coefficient de corrélation Pearson pour toutes les données de plus de 0.99. La fenêtre d'EC d'un faisceau d'électrons de 18 MeV a été décalée avec succès vers 650 nm dans le réservoir d'eau, confirmant sa capacité à stimuler la photoluminescence de CdSe/ZnS, et dans le fantôme simulant les tissus biologiques. La diminution de la taille des champs ainsi que l'augmentation de la profondeur des PQs ont eu pour effet de diminuer le signal, quoiqu'un décalage du signal était encore apparent à 1 cm de profondeur. L'analyse statistique des données nous a confirmé que le bruit n'a pas d'impact significatif sur le signal, mais que le rayonnement peut avoir un impact sur les composantes électroniques du spectromètre.Les résultats de ce travail confirment le potentiel d'application de l'EC pour la dosimétrie en radiothérapie, pour l'imagerie en temps réel et pour la modulation d'intensité des faisceaux en fonction des informations relatives au microenvironnement des tumeurs, comme l'oxygénation. En effet, l'EC est intrinsèque au faisceau d'électrons, est non-ionisante et peut être détectée en dehors du faisceau. De plus, les PQs utilisés dans nos expériences sont photostables et peuvent être modifiés afin d'intégrer des molécules pouvant nous informer sur la microbiologie des tumeurs. Il est prévu que la technique proposée sera applicable à la cartographie de dose en 3D au moyen de la tomographie optique diffuse, à l'imagerie par EC en temps réel et la localisation spatiale durant la radiothérapie, ainsi qu'à la modulation du faisceau en fonction du microenvironnement de la tumeur.
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Hung, Ching-Yi Emily. "Nation Energy System Patterns and Forecasting." Thesis, University of Canterbury. Electrical and Computer Engineering, 2009. http://hdl.handle.net/10092/3100.
Повний текст джерелаАнотація:
This thesis investigates the patterns of each type of energy consumption for fourteen countries, to study the link between energy consumption, economics and population. It was found that for all the countries studied, there is a decrease in energy consumption relative to economic growth. This shows that the world has become less energy based,
and is more efficient in using energy to produce economic wealth.
The carbon dioxide (CO₂) emissions for each fossil fuel type used for electricity generation in New Zealand: coal, gas and oil was also calculated. Gas is the main contributor of CO₂ by electricity generation for New Zealand. New Zealand's CO₂ emissions from electricity generation have nearly tripled in the last 12 years. Despite the environmental concerns of global warming and the Kyoto protocol, there has been a large increase in total CO₂ emitted. This increase has seen a replacement of gas by coal in order to continue to meet the electricity demand of the nation.
New Zealand has a small energy market relative to the global market. World energy market patterns show a recent history of oil declining, coal declining, gas increasing
and the significant presence of nuclear. Renewable energies are insignificant on the
world scene. These are marked contrasts to the New Zealand scene.
Of the renewable energy supply fuels, both hydro and geothermal have been in decline, from before deregulation. This trend will continue in the future if left to market forces.
Although renewable energy may be a solution to New Zealand's energy supply, the increase in market share of other renewable energies to date is limited. They are unlikely to be sufficient to cover New Zealand's energy demand in the near future. With
New Zealand being dependent on the world supply of oil, the expected depletion of the
Maui gas field, the low market share for renewable energy and rising concerns about pollution, the green house effects and global warming, nuclear power is considered an
option in New Zealand.
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Figueres, Fernando, and Elena Popova. "Environmental Kuznets Curve for Carbon Intensity : a Global Survey." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Nationalekonomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-15656.
Повний текст джерелаАнотація:
The Environmental Kuznets Curve is an inverted U-shaped relationship which demonstrates how environmental degradation increases as countries begin to develop and lowers as they become wealthier. The classical EKC measures the effects of GDP per capita (a country’s wealth) on pollu-tion. This paper is a study of the connection of a number of factors- GDP per capita, fossil fuels, al-ternative and nuclear energy, rural population and life expectancy at birth to the Environmental Kuznets Curve. Two econometric approaches are applied in order to test whether the variables have a more pronounced linear or quadratic form. Four income groups of countries are investigated in order to check if the state of development plays a crucial role in environmental deterioration. The results of the study point out that EKC does not apply for the chosen variables. From the regression for GDP, however, it can be concluded that EKC forms in 1990s.
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Tobiasson, John Robert. "Determining H2O Vapor Temperature and Concentration in Particle-Free and Particle-Laden Combustion Flows Using Spectral Line Emission Measurements." BYU ScholarsArchive, 2017. https://scholarsarchive.byu.edu/etd/6497.
Повний текст джерелаАнотація:
There is a growing need for the clean generation of electricity in the world, and increased efficiency is one way to achieve cleaner generation. Increased efficiency may be achieved through an improved understanding of the heat flux of participating media in combustion environments. Real-time in-situ optical measurements of gas temperature and concentrations in combustion environments is needed. Optical methods do not disturb the flow characteristics and are not subject to the temperature limitation of current methods. Simpler, less-costly optical measurements than current methods would increase the ability to apply them in more circumstances. This work explores the ability to simultaneously measure gas temperature and H2O concentration via integrated spectral intensity ratios in regions where H2O is the dominant participating gas. This work considered combustion flows with and without fuel and soot particles, and is an extension of work previously performed by Ellis et al. [1]. Five different combustion regimes were used to investigate the robustness of the infrared intensity integral method first presented by Ellis et al. [1]. These included Post-Flame Natural Gas (PFNG), Post-Flame Medium Wood (PFMW), Post-Flame Fine Wood (PFFW), In-Flame Natural Gas (IFNG), and In-Flame Fine Wood (IFFW). Optical spectra were collected as a function of path length for each regime. Methods for processing the spectra to obtain gas temperature, gas concentration, broadband temperature, and broadband emissivity were developed. A one-dimensional spectral intensity model that allowed for specular reflection, and investigated differences between measured and modeled spectral intensities was created. It was concluded that excellent agreement (within 2.5%) was achieved between optical and suction pyrometer gas temperatures as long as 1) the optical probe and cold target used were well-aligned 2) the path length was greater than 0.3 m and 3) the intensity from broadband emitters within the path was smaller than the gas intensity. Shorter path lengths between 0.15 – 0.3 m produced reasonable temperatures with 7 % error while path lengths of 0.05 m or less were as much as 15% in error or the signal would not effectively process. Water vapor concentration was less accurate being at best within 20% (relative) of expected values. The accurate determination of concentration requires first an accurate temperature concentration as well low broadband participation. Some optical concentrations were in error as much as 85%. The 1-D model was compared to the measurement and it was found that the model peaks were sharper and shifted 0.167 cm-1 compared to the measured data. The reason for the shift can be attributed to the uncertainty of the reference laser frequency used in the FTIR. No conclusion was found for the cause of the sharper peaks in the model. The integrated area of bands used to find temperature and concentration matched well between the model and measured spectrum being typically within 3%.
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Willaime, Julien Michel Yvon. "Use of intensity- and spatial-based image descriptors to characterise and quantify neoplastic lesions in positron emission tomography." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/18787.
Повний текст джерелаАнотація:
Intra-tumour biological heterogeneity is a characteristic shared by all cancers and is thought to contribute to treatment failure. Within-lesion spatial heterogeneity can be qualitatively visualised in Positron Emission Tomography (PET) imaging. Quantifying the variability of the biological processes and the complexity of the signal being measured in PET oncology is essential. The aim of this thesis was to develop and validate intensity- and spatial-based metrics to quantitatively account for the complexity of radiotracer uptake and to annotate intra-tumour PET heterogeneity. Texture analysis was employed to characterise the in vivo tumour heterogeneity of cell proliferation in breast tumours using 18F-fluorothymidine (18F-FLT) PET. The repeatability of the feature measurements was assessed in patients who had two PET scans prior to therapy. Associations between features at baseline and clinical response measured after three cycles of chemotherapy were explored. Associations between feature changes at one week after the start of chemotherapy and clinical response were also explored. Furthermore, the influence of analysis parameters and imaging protocols were studied. A subset of textural features produced reliable measurements and were associated with treatment response. A technique based on multifractal analysis was also developed for characterising the space-filling properties of an object of interest in PET imaging. The derived spatial index was further combined with intensity metrics and the technique was shown to correct for partial volume effects. The method was illustrated on mathematical objects, validated on test-retest 18F-FLT PET clinical data and applied to realistic PET simulations. This work contributes to the demonstration that intensity- and spatial-based image analysis methods can supplement existing methods in PET quantification studies. These techniques provide some improvements on existing methods to derive classical quantitative PET indices and permit extraction of additional information to further characterise patient populations in the clinical setting and in relation to therapy.
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Landmann, Tobias. "A case study for Skukuza estimating biophysical properties of fires using EOS-MODIS satellite data /." Doctoral thesis, [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970359403.
Повний текст джерела
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Tariq, Azeem. "Development and adaptation of water management systems to mitigate greenhouse gas emissions from intensive rice production." Thesis, Montpellier, SupAgro, 2018. http://www.theses.fr/2018NSAM0021.
Повний текст джерелаАнотація:
Pour répondre à la demande de la population croissante, la production de riz doit être augmentée de 40% d’ici 2030. Cependant cette production émet des gaz à effet serre (GES), tel que le méthane (CH4), qui contribue au réchauffement climatique. Les stratégies de gestion, telles que le drainage des sols et la gestion durable des résidus, sont essentielles pour diminuer les émissions de GES des rizières, mais cela entrent souvent en conflit avec les pratiques de gestion des riziculteurs. L'objectif de ce projet était d'étudier le potentiel d'atténuation des GES par des pratiques de drainage et de gestion des résidus et par l’identification des opportunités et les contraintes auxquelles sont confrontés les petits exploitants dans la mise en œuvre des pratiques. Le projet a été élaboré en utilisant une approche interdisciplinaire incluant mésocosme en chambre climatique, des campagnes sur le terrain et une enquête après des agriculteurs au Vietnam. La première étude sur le mésocosme a été menée pour identifier l'impact du drainage en début et mi-saison sur les émissions de CH4 et de N2O par des sols amendés avec des résidus frais et compostés à différents niveaux de sol C (article I). La deuxième étude sur le mésocosme incluait des résidus de riz enrichis en 13C pour comprendre l'effet de la pré-plantation, d’un drainage précoce et à mi-saison sur la contribution des résidus C aux émissions de CH4 (article III). Des expériences de terrain ont été menées pendant deux saisons (printemps et été) pour documenter l'effet de la pré-plantation, du drainage en début et à mi-saison sur les émissions de CH4 et de N2O par des sols modifiés par l’apport de résidus dans deux systèmes de gestion d’eau: un système efficace de gestion de l'eau et un système de contrôle d'eau conventionnel (article II). Trente-cinq petits producteurs de riz ont été interviewés pour évaluer la diversité des pratiques de gestion des terres dans la région et comprendre leurs pratiques de culture, leurs défis et leurs contraintes à l'échelle de la rizière. Quatre ateliers ont été menés avec des agriculteurs, des conseillers agricoles locaux et régionaux pour concevoir et évaluer les pratiques de production de riz adaptées au climat, basées sur la gestion de l'eau et des résidus (article IV). Les études de laboratoire et de terrain ont montré que les pratiques de drainage (pré-plantation et drainage précoce) pouvaient atténuer les émissions de GES sans compromettre le rendement du riz. Au laboratoire, le drainage avant plantation a considérablement réduit les émissions de CH4 de 70 à 80%, alors que sur le terrain, le drainage se montre moins efficace dans la réduction des émissions de CH4 en raison des activités opérées par les agriculteurs avant transplantion. Dans l’étude de terrain, le drainage précoce et en mi-saison a diminué les émissions de CH4 de 67% et 43% dans les systèmes comprenant une gestion de l’eau efficaces et inefficaces. Au laboratoire, l’addition d’un drainage en début et mi-saison a réduit les émissions de CH4 de 75 à 90%. Sur le terrain, le système efficace de contrôle de l'eau associé avec une bonne aération des sols a considérablement augmenté le potentiel de diminution du CH4 des sols drainés et modifiés par les résidus. L'étude isotopique a indiqué que l'aération des sols au stade précoce (pré-plantation ou début de saison) réduit les émissions de CH4 dérivés des résidus de 57 à 87%. Cependant, les résultats ont mis en évidence que l’amélioration des pratiques de drainage impactaient très peu les émissions de N2O. Les résultats de l'étude participative ont souligné l'importance d'impliquer les agriculteurs et les acteurs locaux dans la conception des systèmes d'atténuation des GES. Ces résultats ont mis en évidence les contraintes et les opportunités possibles pour la mise en œuvre réussie des stratégies d'atténuation des GES dans les rizières des petits exploitantsRice production needs to increase by 40% to meet the demand of the world’s growing population by 2030, yet rice production contribute to global warming with elevated GHG emissions, particularly of methane (CH4). Management strategies, such as drainage of paddy soils & sustainable residue management are essential in order to mitigate GHG emission from rice systems, but they often conflict with the practical management preferences of rice farmers. The objective of this project was to investigate the GHG mitigation potential of drainage practices and residue management techniques, and to identify the constraints and opportunities faced by smallholders in the implementation of mitigation practices under local conditions. The project was formulated using an interdisciplinary approach that included two mesocosm studies in growth chamber, two field campaigns and a field survey of farmers in Vietnam. First mesocosm study was conducted to verify the impact of early season drainage and midseason drainage on CH4 and N2O emissions from fresh and composted residue-amended soils at different soil C levels (Paper I). Then second mesocosm study was conducted using 13C-enriched rice residue to understand the effect of pre-planting, early-season and midseason drainage on the residue carbon contribution to CH4 emissions (Paper III). Field experiments based on farmers’ field conditions were conducted for two seasons (spring and summer) to document the effect of pre-planting, early-season and midseason drainage on CH4 and N2O emissions from residue-amended soils under two field water management systems: an efficient field water control system and a conventional, inefficient field water control system (Paper II). Thirty-five smallholder rice farmers were interviewed to capture the diversity of different land management practices in the area and understand their cropping practices, challenges and constraints faced at field scale. Four workshops were conducted with farmers, local agricultural advisors and regional stakeholders to design and assess the climate-smart rice production practices, based on water and residue management (Paper IV). The lab and field studies showed that drainage practices (pre-planting and early season drainage) had the potential to mitigate GHG emissions without compromising rice yield. Pre-planting drainage greatly reduced CH4 emissions in the lab experiment by 70-80%, while in field condition pre-planting drainage had less effect on CH4 emission reduction due to constraints with farmers’ field operations before transplanting. Early season drainage reduced CH4 emissions in both lab and field experiments. In field study, early plus midseason drainage lowered the CH4 emissions by 67% and 43% in the efficient and inefficient field water management systems respectively. In lab, early plus midseason drainage lowered CH4 emissions by 75-90 %. The efficient field water control system and good soil aeration significantly increased the CH4 mitigation potential of the drainage regimes from residue-amended soils. The isotopic study in lab indicated that soil aeration in the early stage (pre-planting or early season) reduced the residue-derived CH4 emissions by 57-87%. The results highlighted that the effects of improved drainage practices on N2O emissions were very low when considering the total GHG effects of CH4 and N2O. The results of the participatory study highlighted the importance of involving farmers and local stakeholders in the process of designing the mitigating systems. The active involvement of farmers and local stakeholders in the process of designing, testing and assessing the water management systems highlighted the constraints and feasible options for successful implementation of GHG mitigation strategies in smallholders’ rice fields
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Wijewardane, Samantha. "Assessment of Methods to Manipulate Thermal Emission and Evaluate the Quality of Thermal Radiation for Direct Energy Conversion." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4420.
Повний текст джерелаАнотація:
ABSTRACT
Control of spectral thermal emission from surfaces may be desirable in some energy related applications, such as nano-scale antenna energy conversion and thermophotovoltaic conversion. There are a number of methods, from commercially available paints to advanced surface gratings that can be used to modify the thermal emission from a surface. To find out the proper emission controlling technique for a given energy conversion method all the surface emission controlling methods are comprehensively reviewed regarding the emission control capabilities and the range of possible applications. Radiation with high degree of coherence can be emitted using advanced surface emission controlling techniques. The entropy of the thermal radiation, and therefore the exergy, is a function of the degree of coherence. A methodology is presented to calculate the exergy of partially coherent wave fields so that the radiation fields can be evaluated based on exergy. This exergy method is extended to develop a rigorous evaluation criterion for thermal emission controlling methods used in frequency dependent energy conversion applications. To demonstrate these developed criteria using actual data, a surface plasmon emitter is designed and fabricated. Also, possible ways of improving the emitter performance and the research needed to be carryout to fabricate cost effective emitters are described.
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Muller, Jesse Michael. "Improving fertiliser nitrogen recovery and mitigating nitrous oxide emissions from intensive vegetable cropping systems in South East Queensland." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/132721/1/Jesse_Muller_Thesis.pdf.
Повний текст джерелаАнотація:
This thesis is a study into the efficacy of cropping methods Australian vegetable growers can adopt to increase nitrogen fertiliser efficiency, reduce nitrogen fertiliser application rates and reduce nitrous oxide emissions. The experiment, conducted in the Lockyer Valley (South East Queensland, Australia) investigated the utilization of the DMPP and Piadin nitrification inhibitors to achieve these research objectives. Outcomes from this research will help growers to reduce nitrogen fertiliser application rates and reduce greenhouse gas emissions without reducing yields.
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Codruta, Maris Stefania. "Effect of nitrogen fertilization and water management of GHGs (N2O, CO2 and CH4) emissions from intensive Mediterranean agricultural systems." Doctoral thesis, Universitat de Lleida, 2015. http://hdl.handle.net/10803/365310.
Повний текст джерелаАнотація:
Els gasos amb efecte d'hivernacle (GEH) procedents de l'agricultura depenen de la gestió del reg i dels fertilitzants. L'objectiu d'aquesta tesi va ser identificar les principals estratègies per a mitigar els GEH i obtenir un rendiment màxim: (i) reg continu (CI)/intermitent (II) en un camp d'arròs; (ii) fertilització de fons amb gallinassa (CM), purí porcí (PS), urea (U) o sulfat d'amoni (AS) en un camp d'arròs; (iii) incorporació/eliminació de rostoll de panís amb diferents dosis de N mineral, i (iv) reg enterrat (SDI)/superficial por degoteig (DI) combinat amb N mineral aplicat via fertirrigació amb i sense DMPP en un cultiu súper-intensiu d'olivera.
El reg continu minimitza significativament les emissions dels camps d'arròs al mateix temps que garanteix un alt rendiment. L'aplicació de purí porcí en dosis agronòmiques determina alts rendiments i minimitza els GEH.
Respecte als GEH i al rendiment del panís, el tractament control va ser la millor opció, independentment de la gestió del rostoll. Així mateix, l'aplicació de DMPP + 50 kg N ha-1 + reg superficial per degoteig (DI) va ser la millor opció pel cultiu d'olivera súper-intensivaLos emisión de gases con efecto invernadero (GEI) procedentes de la agricultura depende de la gestión del riego y de los fertilizantes. El objetivo de esta tesis fue identificar las mejores estrategias -de entre las siguientes- para mitigar los GEI manteniendo un rendimiento máximo: (i) riego continuo (CI)/intermitente (II) en un arrozal, (ii) la fertilización de fondo con gallinaza (CM) , purín porcino (PS), urea (U) o sulfato amónico (AS) en un arrozal con AS en cobertera, (iii) la incorporación/eliminación del rastrojo con diferentes dosis de N mineral en el cultivo del maíz, (iv) el riego por goteo enterrado (SDI)/superficial (DI) en combinación con N mineral aplicado vía fertirrigación con y sin DMPP en un olivar súper-intensivo. El CI mitiga significativamente las emisiones del arrozal al tiempo que garantiza el rendimiento máximo. La aplicación de purín porcino a dosis agronómicas proporciona altos rendimientos y minimiza los GEI. Considerando las emisiones de GEI y el rendimiento del maíz, el tratamiento control fue la mejor opción, independientemente de la gestión del rastrojo. La aplicación de DMPP + 50 kg N ha-1 + DI fue la mejor opción para el cultivo súper-intensivo de olivo.
Greenhouse gases emissions from agriculture depend on irrigation and fertilisation management. The objective of this thesis was to identify the less emitting management strategies among the following, compatible with a feasible yield: (i) continuous (CI)/intermittent irrigation (II) on rice, (ii) background fertilization with chicken manure (CM), pig slurry (PS), urea (U) or ammonium sulphate (AS) and topdressing on rice, (iii) stover incorporation/removal with different doses of mineral N and, (iv) subsurface (SDI)/surface drip irrigation (DI) in combination with mineral N fertigation with and without DMPP on a super-intensive olive tree orchard. Continuous irrigation significantly mitigated emissions from paddy fields while ensuring the highest yield. Pig slurry application at agronomic doses allowed high yields and minimized emissions. Based on emissions and maize yield, the control treatment was the best option regardless of stover management. Applying DMPP with 50 kg N ha-1+ drip irrigation (DI) was the best option for the olive tree orchard.
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Brown, Darren. "Energy intensive and trade exposed (EITE) Portland cement manufacturing sector : developing policy and supporting mechanisms to minimize emissions leakage." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62118.
Повний текст джерелаАнотація:
Government intervention to limit and reduce nocuous air emissions from industrial applications
focuses on protecting human health and the environment. Unfortunately, energy intensive and
trade exposed (EITE) industries in developed countries are susceptible to competitive pressures
with their counterparts in jurisdictions that have relaxed compliance requirements, such as
emerging markets. Along with the loss of production to the emerging market, the associated air
emissions are also displaced. The goal of this research is to develop policy and supporting
mechanisms to minimize the leakage of air emissions from trade. The main objectives carried
out to support this goal included: identifying a surrogate EITE industry and establishing a
baseline air emissions inventory; comparing the environmental performance of the surrogate in
the developed and emerging market; and, evaluating policy options and supporting mechanisms. As an EITE industry the Portland cement manufacturing sector was identified as the industrial
surrogate. Life Cycle Impact Assessment (LCIA) methodology was applied to the cement
manufacturing sectors in China and Canada for comparative purposes. Nocuous air emissions of
oxides of nitrogen (NOx), sulphur dioxide (SO₂), particulate matter (PM) and carbon monoxide
(CO) were evaluated in terms of intensity per tonne of Portland cement, and, in respect of their
contribution to winter smog. In terms of impact to human respiratory health, using Disability
Adjusted Life Years (DALYs), Portland cement produced in China had more than twice the
impact of cement produced in Canada. Using the example of cement exported from China, policy options were devised to manage emissions leakage from Canada. These policy options investigated combinations of open, restricted and closed borders with direct, partial, and no support for domestic manufacturers. Analytic Hierarchy Process (AHP) in conjunction with the three actionable solidarities of Cultural Theory was applied. Results indicated a restricted border with partial support was most strongly favored, and, of the policy mechanisms reviewed, a verification process was supported. Under the Canadian Environmental Protection Act, 1999 (CEPA) an air quality agreement can be established to include this policy framework between China and Canada. The proposed approach for EITE cement industry can be extended to other industries and international trade.Applied Science, Faculty of
Engineering, School of (Okanagan)
Graduate
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Batalha, Camila Delveaux Araujo. "Grazing strategies, animal performance and environmental sustainability in intensive pasture-based milk production systems." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-15032019-125835/.
Повний текст джерелаАнотація:
In Brazilian livestock, and its diverse ways of production, the management of grazing animals is known as the lowest return on investment on land use opportunities. Nevertheless, among different types of milk production systems, it is noted that the use of pasture grazing is a common feature between them. Thus, to achieve profitability and maintain system sustainability, the identification of the most adequate and efficient pasture management practices, can maximize production per cow and production per unit area. The low efficiency of this method of production, also classifies the national livestock as the major source of environmental pollution due the emission of pollutants, such as greenhouse gases and nitrogen. The adoption of pasture management techniques respecting forage physiological limits and increasing digestibility of nutrients, can reduce the excretion of nutrients and the production of methane per kilo of milk produced on the environment. The objectives of this thesis were to investigate metabolic variables, greenhouse gas emissions and animal performance for dairy cows grazing elephant grass subjected to rotational stocking strategies. Chapter 1: In this study was to evaluate two strategies of grazing management: pre-grazing targets of 95% versus maximum canopy light interception (LI). In intensive pasture-based milk production systems, the management based on LI95% allows lactating cows to have access to pastures with lower proportion of stems, with higher proportions of young leaves better chemical composition and perform an efficient grazing with lower forage losses. Therefore, the LI95% pasture management strategy results in higher energy intake, higher milk production per cow, higher stocking rates of pasture and higher milk yield per area. Also, the strategy allows the decrease of methane emissions per net energy intake when comparing to management based on LIMax. However, dietary N use efficiency did not increase with this management practice. Chapter 2: The objective of the second study was to evaluate the effects of paddock allocation time (a.m. vs. p.m.) on milk production, ruminal variables and efficiency of N use of mid-lactation dairy cows. In intensive pasture-based milk production systems, allocating cows on new paddocks on p.m. time has no effect on forage intake and milk production of grazing mid-lactation cows. However, the higher content of nonstructural carbohydrate of forage from p.m. pastures increases the yield of microbial protein, decreases milk urea nitrogen and tends to increase the yields of milk protein and milk casein compared to a.m. pastures. Throughout this thesis there were an improvement on nutritive value of forage adopting LI95% as a pre- grazing target and forage grazed at p.m. Therefore, the time of allocation on paddock should be used along with LI95% as fine-tune in intensive pasture-based milk production systems.No Brasil, a produção animal em pastagens é reconhecida por ser uma atividade pouco competitiva frente a outras oportunidades de uso da terra. Embora sejam inúmeros os tipos de sistemas de produção de leite no Brasil, nota-se que a utilização de pastagens é característica comum. Assim, a identificação de práticas adequadas e eficientes de manejo do pastejo contribuirá com aumento da produção por vaca e por unidade de área, além de contribuir para a sustentabilidade do sistema. A baixa eficiência do uso dos recursos naturais tem classificado a pecuária nacional como uma importante fonte de poluição ambiental devido à emissão de poluentes, como gases de efeito estufa e excreção de nitrogênio. A adoção de técnicas de manejo de pastagens respeitando os limites fisiológicos da forrageira e aumentando sua digestibilidade, podem reduzir a produção de metano por quilo de leite produzido no ambiente e a excreção de nutrientes. Os objetivos desta tese foram investigar variáveis metabólicas e desempenho animal de vacas leiteiras em capim-elefante cv. cameroon submetido a estratégias de pastejo rotativo. Capítulo 1: Neste estudo foram avaliadas duas estratégias de manejo de pastejo: meta de pré-pastejo de 95% versus máxima interceptação luminosa (IL). Em sistemas intensivos de produção de leite à pasto, o manejo baseado no IL95% permite que vacas tenham acesso a pastos com maior relação folha: colmo, menores perdas de forragem, resultando em uma forragem com melhor composição química. Os animais pastejando forragem com IL95% tiveram maior consumo de matéria seca e energia, com maior produção de leite por vaca e taxa de lotação resultando em maior produção de leite por área. Além disso, a estratégia permite a diminuição das emissões de metano por consumo de energia líquida quando comparado a máxima IL. No entanto, a eficiência do uso de N não aumentou com essa prática de manejo. Capítulo 2: O objetivo do segundo estudo foi avaliar os efeitos do período de início pastejo (a.m. ou. p.m.) na produção de leite, variáveis ruminais e eficiência de uso de N de vacas leiteiras no terço médio da lactação. Em sistemas intensivos de produção de leite à pasto, o pastejo de novos piquetes no período da tarde não teve efeito sobre o consumo de forragem e produção de leite de vacas no terço médio da lactação. No entanto, o maior teor de carboidratos não fibrosos da forragem ao final do dia possibilitou o aumento da síntese de proteína microbiana, redução do nitrogênio uréico no leite e apresentou tendência para aumento da produção de proteína e caseína do leite em comparação à vacas que iniciaram o pastejo no período da manhã. Ao longo dos estudos desta tese houve uma melhora no valor nutritivo da forragem adotando IL95% e da forragem pastejada no período da tarde. Assim, o pastejo no período da tarde deve ser adotado juntamente com IL95% como ajuste fino em sistemas intensivos de produção de leite à base de pasto.
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Billstein, Tova. "On Conducting a Life Cycle Assessment of Network Traffic : A Qualitative Analysis of Current Challenges and Possible Solutions." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-297498.
Повний текст джерелаАнотація:
There is a growing demand for climate reporting of digital solutions and Internet services. However, the impacts of data transmission have historically been the least studied part of the ICT sector and in the few studies that exist, the magnitude of Internet energy intensity varies by a scale as large as 20,000. This indicates that the assessment of network traffic is a complex task, and there is currently no consensus of how to correctly assess it. In an attempt to guide process development within the area, this report sought to identify and address potential challenges with assessing the environmental impact of network traffic during its life cycle. This was completed through a combination of a literature review and semi-structured interviews with experts in the field. Several areas in the form of knowledge gaps, unsolved methodological issues, and areas in need of further development were identified and addressed. Eight key challenges were identified and relate to the areas of system boundaries, data collection methods, energy intensity metrics, transparency and data availability, age of data, allocation procedures, assumptions on inventory level, and impact categories. In an attempt to address said challenges, several suggestions on how to proceed were presented, as well as areas in need of further investigation. It was furthermore found that the sector should strive to agree upon a number of parameters of significance to enable future harmonized studies of the environmental impact of network traffic during its life cycle.Efterfrågan på klimatrapportering av digitala lösningar och Internettjänster ökar allt mer. Samtidigt är effekterna av datatrafik historiskt sett den minst studerade delen av IKT-sektorn, och i de få studier som finns varierar storleken på Internets energiintensitet med en skala på 20 000. Detta indikerar att bedömningen av nätverkstrafik är en komplex uppgift, och i nuläget saknas en konsensus kring hur det bäst kan mätas. I ett försök att vägleda processutveckling inom området försökte rapporten identifiera och analysera potentiella utmaningar som kan uppstå när man bedömer miljöpåverkan av nätverkstrafik under dess livscykel. Med en kombination av en litteraturstudie och halvstrukturerade kvalitativa forskningsintervjuer med experter inom forskningsområdet identifierades och behandlades ett flertal områden i form av kunskapsluckor, olösta metodologiska frågor och områden i behov av vidareutveckling. Resultatet visade att åtta utmaningar av hög relevans existerar inom områdena systemgränser, datainsamlingsmetoder, energiintensitetsmätvärden, transparens och datatillgänglighet, snabb teknikutveckling, allokering, antaganden och miljöpåverkningskategorier. I ett försök att ta itu med de nämnda utmaningarna presenterades ett flertal förslag till lösningar samt områden som behöver undersökas ytterligare i framtiden. Det konstaterades dessutom att sektorn behöver sträva efter att enas om ett antal parametrar av betydelse för att möjliggöra framtida harmoniserade studier av nätverkstrafikens miljöpåverkan under dess livscykel.
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Snyman, LW, Plessis M. Du, and H. Aharoni. "Injection-Avalanche-Based nþpn Silicon Complementary Metal Oxide–Semiconductor Light-Emitting Device (450 – 750 nm) with 2-Order-of-Magnitude Increase in Light Emission Intensity." Japanese Journal of Applied Physics, 2007. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000813.
Повний текст джерелаАнотація:
In this paper, we report on an increase in emission intensity of up to 10 nW/mm2 that has been realized with a new novel two
junction, diagonal avalanche control, and minority carrier injection silicon complementary metal–oxide–semiconductor
(CMOS) light emitting device (LED). The device utilizes a four-terminal configuration with two embedded shallow nþp
junctions in a p substrate. One junction is kept in deep-avalanche and light-emitting mode, while the other junction is forward
biased and minority carrier electrons are injected into the avalanching junction. The device has been realized using standard
0.35 mm CMOS design rules and fabrication technology and operates at 9V in the current range 0.1– 3 mA. The optical output
power is about one order of magnitude higher for previous single-junction nþp light-emitting devices while the emission
intensity is about two orders of magnitude higher than for single-junction devices. The optical output is about three orders of
magnitude higher than the low-frequency detectivity limit of silicon p–i–n detectors of comparable dimensions. The realized
characteristics may enable diverse optoelectronic applications in standard-CMOS-silicon-technology-based integrated
circuitry.
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Zhang, Jiao. "Map making from transit interferometers observations for 21cm Intensity Mapping experiments : Application to Tianlai and PAON-4." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS158/document.
Повний текст джерелаАнотація:
L'analyse des propriétés statistiques de la distribution de la matière dans le cosmos (Grandes Structures, LSS or Large Scale Structure) est l'une des principales sondes cosmologiques qui permettent l'étude du modèle standard cosmologique, en particulier les paramètres caractérisant la matière noire et l'énergie noire. Les Oscillations Acoustiques Baryoniques (BAO's) sont l'une des mesures qui peuvent être extraites de l'étude de la distribution de matière à grande échelle (LSS).L'observation de la distribution cosmique de la matière à partir de l'émission à 21 cm de l'hydrogène atomique neutre (HI) est une nouvelle méthode, complémentaire des relevés optiques pour cartographier la distribution de la matière dans le cosmos. La méthode de cartographie d'intensité (Intensity Mapping) a été proposée depuis moins d'une dizaine d'années comme une méthode efficace pour cartographier en trois dimensions l'émission radio à 21 cm. Elle n'implique en particulier pas la détection des objets individuels (galaxies), et peut donc être effectué avec des instruments plus modestes en taille que ceux comme SKA ou FAST qui sont conçus pour détecter les galaxies à 21 cm à des distances cosmologiques. Des interféromètres radio utilisant un ensemble de réflecteurs cylindriques ou paraboliques fixes, observant le ciel en mode transit sont adaptés à la cartographie d'intensité. Le mode d'observation spécifique de ce type de radio télescope en cartographie d'intensité est étudié dans le cadre de ce travail de thèse. On montre en particulier qu'une méthode spécifique de reconstruction des cartes du ciel à partir des visibilités peut être appliquée aux observations de ces interféromètres fonctionnant en mode transit. Cette méthode correspond à la décomposition en modes m des harmoniques sphériques et est très performante pour la reconstruction de grandes zones du ciel observées en mode transit. Un code de reconstruction fondé sur ce principe a été développé, ainsi que différents critères de comparaison des performances instrumentales, comme le lobe d'antenne synthétisé, le spectre de bruit sur les cartes reconstruites et la réponse globale de l'instrument dans le plan (l,m) des harmoniques sphériques. La méthode a été appliquée à différentes configurations des interféromètres composés de réflecteurs paraboliques ou cylindriques dans le cadre des projets PAON-4 et Tianlai. Outre l'optimisation des configurations des interféromètres Tianlai et PAON-4, le travail présenté inclut une première application de la méthode aux données PAON-4The analysis of the statistical properties of the distribution of matter in the cosmos (LSS or Large Scale Structure) is one of the main cosmological probes that allow the study of the cosmological standard model, in particular the parameters characterizing dark matter and dark energy. Baryonic Acoustic Oscillations (BAO's) are one of the measurements that can be extracted from the study of matter distribution in large-scale structure (LSS).The observation of the cosmic distribution of the matter from neutral atomic hydrogen (HI) 21 cm emission is a new method, complementary to the optical observation to map the distribution of matter in the cosmos. In the last decade, the Intensity Mapping method has been proposed as an effective method for mapping the 21cm radio emission in three dimensions. In particular, it does not require the detection of individual objects (galaxies), and can therefore be performed with instruments smaller in size than those such as SKA or FAST, which are designed to detect 21 cm galaxies at cosmological distances. A radio interferometer using a set of fixed cylindrical or parabolic reflectors observing the sky in transit mode are suitable instruments for intensity mapping surveys. The specific observational mode from this type of radio telescope by intensity mapping is studied in the context of this thesis. We show in particular that a specific sky maps reconstruction method from the visibilities can be applied to the observations of these interferometers operating in transit mode. This method corresponds to the m-modes decomposition of the spherical harmonics and is very efficient for the reconstruction of large sky areas observed in transit mode. A reconstruction code based on this principle has been developed, as well as different criteria for the comparison of instrumental performances, such as the synthesized antenna lobe, the noise spectrum of the reconstructed maps and the overall instrument response in the spherical harmonics (l,m) plane. The method has then been applied to different configurations of interferometers composed of parabolic or cylindrical reflectors in the PAON-4 and Tianlai projects. In addition to optimizing the Tianlai and PAON-4 interferometer configurations, the work presented here includes a first application of the method to the PAON-4 data
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Dimba, A. A. "A comparative study of emission bandshapes in alloy films of hydrogenated amorphous silicon with nitrogen or carbon and pl-efficiency dependence on excitation intensity and temperature." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266005.
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Piaget, Stève Marc. "Greenhouse gas intensity of South Africa's production and consumption : a study of the relationship between economic growth, income distribution and greenhouse gas emission in South Africa." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/5416.
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Sperlich, B., D. P. Born, K. Kaskinoro, K. K. Kalliokoski, and Marko Laaksonen. "Squeezing the Muscle : Compression Clothing and Muscle Metabolism during Recovery from High Intensity Exercise." Mittuniversitetet, Avdelningen för hälsovetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-18973.
Повний текст джерелаАнотація:
The purpose of this experiment was to investigate skeletal muscle blood flow and glucose uptake in m. biceps (BF) and m. quadriceps femoris (QF) 1) during recovery from high intensity cycle exercise, and 2) while wearing a compression short applying ~37 mmHg to the thigh muscles. Blood flow and glucose uptake were measured in the compressed and non-compressed leg of 6 healthy men by using positron emission tomography. At baseline blood flow in QF (P = 0.79) and BF (P = 0.90) did not differ between the compressed and the non-compressed leg. During recovery muscle blood flow was higher compared to baseline in both compressed (P<0.01) and non-compressed QF (P<0.001) but not in compressed (P = 0.41) and non-compressed BF (P = 0.05; effect size = 2.74). During recovery blood flow was lower in compressed QF (P<0.01) but not in BF (P = 0.26) compared to the non-compressed muscles. During baseline and recovery no differences in blood flow were detected between the superficial and deep parts of QF in both, compressed (baseline P = 0.79; recovery P = 0.68) and non-compressed leg (baseline P = 0.64; recovery P = 0.06). During recovery glucose uptake was higher in QF compared to BF in both conditions (P<0.01) with no difference between the compressed and non-compressed thigh. Glucose uptake was higher in the deep compared to the superficial parts of QF (compression leg P = 0.02). These results demonstrate that wearing compression shorts with ~37 mmHg of external pressure reduces blood flow both in the deep and superficial regions of muscle tissue during recovery from high intensity exercise but does not affect glucose uptake in BF and QF. © 2013 Sperlich et al.:doi 10.1371/journal.pone.0060923
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Baily, A. "Spatial and temporal variations in nitrous oxide emissions and groundwater nitrate, determined using stable isotope techniques, at an intensive dairy farm in south east Ireland." Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546006.
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Fikru, Mahelet Getachew. "Mergers and Acquisitions with a Flexible Policy Regime: Theoretical and Empirical Analysis." OpenSIUC, 2011. https://opensiuc.lib.siu.edu/dissertations/325.
Повний текст джерелаАнотація:
The research examines what drives Mergers and Acquisitions (M&As) using a theoretical and empirical approach. The theoretical part uses flexible optimal policies which adjust to changes in the market structure following a merger. The empirical part tests the major theoretical predictions to identify determinants of M&As in advanced economies. Chapters 1 and 2 consider M&As among firms in a pollution-intensive sector. Chapter 1 shows that identical polluting firms engage in M&As only if environmental policies are flexible. Chapter 2 shows that the flexibility of environmental policy increases the incentive to merge among heterogeneous firms. In addition, with flexible policy highly polluting firms have the highest incentive to merge than less polluting firms in a given sector. The empirical evidence suggests that the decision of manufacturing firms to engage in M&As is affected by environmental policy and firms may engage in merger deals in anticipation of a change in policy. Chapter 3 shows that with a flexible consumption tax firms in a bigger, more efficient country takeover firms in a smaller, less efficient country. The incentive to merge increases with the efficiency and market size of the host country. The empirical result obtained from 7 OECD countries shows that market size and firm efficiency play a major role in triggering international mergers.
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Bartsch, Jennifer Verfasser], and Tunga [Akademischer Betreuer] [Salthammer. "Sensorische Bewertung von Emissionen aus Konsumgütern und Bauprodukten mittels GC-Olfaktometrie, empfundener Intensität und Hedonik / Jennifer Bartsch ; Betreuer: Tunga Salthammer." Braunschweig : Technische Universität Braunschweig, 2017. http://d-nb.info/1175817856/34.
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