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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Corporate social responsibility of African and Middle East mobile operators towards climate change and the potential impact of its carbon footprint

Biewenga, Reiner 08 1900 (has links)
Research report, presented to the SBL Unisa, Midrand. / The current and future anticipated changes in the earth’s climate are a concern that has captured business’s and governments’ global attention. Climate change and its potential impacts cannot be ignored as there is ample evidence that global warming is indeed the result of anthropogenic greenhouse gas emissions. The mobile operator in Africa and the Middle East (ME) operates on continents and in parts of the world, predicted by scientists as the most vulnerable to the effects of climate change. The mobile operator in Africa and the Middle East is moreover an emitter of significant amounts of CO2 and this exacerbates the serious environmental climate change problem that humankind faces. This research paper addresses the Corporate Social Responsibility of African and Middle East (ME) mobile operators, and its Carbon Footprint. The main objectives of the research are to identify strategic risks and opportunities and the implications for the mobile operator and to determine its Greenhouse Gas emissions. The performance against targets and plans to reduce GHG emissions are also reviewed. The research is based on the questionnaire of the Carbon Disclosure Project (CDP) initiative. A shortened and modified version of the CDP was designed and emailed to two major mobile telecom operators both operating in Africa and the Middle East. It is postulated that the telecommunications industry is at an inflection point where significant changes must take place in the way energy requirements are managed. This in turn could have a positive effect on reducing its carbon footprint, benefit corporate reputation and at the same time earn “green miles” in the subscriber’s minds. The research reached the main conclusion that the mobile operators’ investigated do not yet have strategies, systems and reporting in place to be counted as “good corporate citizens” concerning their environmental responsibility. The research further concluded that a proactive strategic intent is a necessity to achieve this goal. In short: The Corporate Social Responsibility of African and Middle East mobile operators indeed has a positive effect on its Carbon Footprint.
32

Contribuição da produção confinada de suínos na emissão de amônia e gases de efeito estufa mediante avaliação das metodologias continua e simplificada / Contribution of swine confined production in ammonia emissions and greenhouse effect gases through evaluation of continuous and simplified methodologies

Pecoraro, César Augusto 04 February 2015 (has links)
O impacto ambiental gerado pelas atividades pecuárias sobre o meio ambiente desperta cada vez mais atenção para estudos de avaliação do potencial poluidor das atividades. Essas atividades contribuem significativamente para as emissões de amônia e gases de efeito estufa. A amônia por sua vez contribui para a eutrofização e acidificação dos ecossistemas. Gases de efeito estufa (GEE), incluindo o dióxido de carbono (CO2), metano (CH4), óxido nitroso (N2O) e vapor de H2O são considerados os principais gases responsáveis pelo mecanismo de aquecimento global e as alterações climáticas. Atualmente, a carne suína é a mais consumida no mundo, estima-se que seu consumo aumentará nos próximos anos e, para atender esta demanda, os sistemas produtivos de suínos deverão ampliar sua capacidade produtiva para abastecer o mercado consumidor crescente. A avaliação ambiental dos sistemas de produção de suínos torna-se essencial para garantir a sustentabilidade do setor. Assim, pelo exposto, essa pesquisa tem como objetivo caracterizar as emissões de amônia e gases de efeito estufa em uma unidade de produção de suínos na fase fisiológica de crescimento e terminação utilizando duas metodologias: a contínua e a simplificada. Além disso, pretendemos verificar os resultados obtidos pelas duas metodologias por meio do balanço de nutrientes: este permite avaliar a coerência dos dados obtidos pelas duas metodologias. E por fim, correlacionar as emissões gasosas à variável climática temperatura. O estudo foi desenvolvido em uma granja comercial, no município de Concórdia - SC. A mensuração dos gases foi realizada segundo as recomendações das metodologias: contínua e simplificada. As concentrações dos gases no ar foram mensuradas pelo analisador de gás (INNOVA 1412). As emissões gasosas médias foram calculadas considerando a taxa de ventilação e as diferenças de concentração de gases entre o ar interior e exterior da instalação. O fluxo de emissão obtido pela metodologia simplificada em [g. suíno-1. hora-1] foram 2,689 para o CO2, 0,30 para o N2O, 4,39 para o CH4, 13,55 para o NH3 e 3,273 para água. O fluxo obtido para a metodologia contínua em [g. suíno-1. hora-1] foi de 574 para CO2, 0,67 para o N2O, 19,50 para o CH4, 5,84 para o NH3 e 7,239 para vapor de água. Em comparação ao balanço de massa, a metodologia simplificada apresentou maior coerência em relação aos dados obtidos. / The environmental impact caused by the livestock activities is increasing the number of researches about it, taking into consideration the pollution effects in the environment. The agricultural activities have a great contribution to ammonia\'s and greenhouse gases\' emissions. Ammonia contributes to eutrophication and acidification of ecosystems. Greenhouse gases (GEE), including CO2, CH4, N2O and vapour of H2O are considered the main responsible gases for the global warming and the climate changes. Nowadays, the pig flash is the most consumed one worldwide and this consume tends to continue increasing in the next years. In order to attend this request, the swine production systems must extend their productive capacity to supply the consumer market. The environmental evaluation of swine production systems has been considered essential to guarantee the sustainability of this sector. Taking into consideration this situation, this research aims at characterizing the ammonia\'s and greenhouse gases\' emissions in one swine production installation in the growth physiological stage and in the terminating stage, basing ourselves in two methodologies: the continuous and the simplified ones. Furthermore, we aim at verifying the obtained results by these two methodologies, through nutrient balance: this one enables to evaluate the data\'s consistency using both methodologies. And finally, we objective to correlate the gas emissions to the temperature (climatic variable). This research was developed in commercial farm in Concórdia - SC. The gas mensuration was accomplished by the two cited methodologies: the continuous and the simplified. The concentrations of gases in the air were measured by the gas analyzer (INNOVA 1412). The average gas emissions were estimated, taking into consideration the ventilation rate and the concentration differences of gases between the interior and exterior part of the installation. The emission flow obtained by the simplified methodology in [g. swine-1. hour-1] was 2,689 to CO2, 0,30 to N2O, 4,39 to CH4, 13,55 to NH3 and 3,273 to water. The emission flow obtained by the continuous methodology in [g. swine-1. hour-1] was 574 to CO2, 0,67 to N2O, 19,50 to CH4, 5,84 to NH3 and 7,239 to water vapor. Comparing theses values to the mass balance, the simplified methodology presented a greater consistency in relation to the obtained data.
33

Redução dos impactos ambientais causados por emissões de gases no transporte marítimo. / Reduction of the environmental impacts caused by the maritime transport.

Montoya Cisneros, Juan Carlos 07 November 2011 (has links)
O transporte marítimo depende essencialmente da energia dos derivados do petróleo e, em conseqüência, produz emissões de CO2, SOX, NOX e material particulado entre outros. Hoje o transporte aquaviário responde por aproximadamente 4,5% das emissões de carbono, 4% das emissões de óxidos de enxofre e 7% das emissões de oxido de nitrogênio. Se a expansão desse modal de transporte se mantiver nos próximos anos, como se tem previsto, a sua participação na emissão destes tipos de poluentes deve aumentar e, certamente, haverá pressões da sociedade para introdução de medidas que contenham esse aumento. Pode-se afirmar que os poluentes gerados pelo Transporte Marítimo são resultado de deficiência em projeto de navios e de seus sistemas, de uma má gestão operacional, e inclusive da ausência de medidas de regulamentação mais rigorosas. O estudo se concentra em estudar dois destes pontos. O primeiro se refere ao desenvolvimento do projeto do navio e da instalação propulsora com a preocupação de reduzir o consumo de energia. Isso implica em alterações nos projetos e seus sistemas de propulsão, tirando melhor proveito da tecnologia disponível no mercado, bem como análise da viabilidade de uso de fontes alternativas de energia. O segundo ponto se refere ao processo de gestão operacional, com ênfase na redução da emissão de poluentes. Serão examinados exemplos práticos que sustentem as reduções e benefícios, por exemplo, a redução de velocidade do navio. Por ultimo foram expostas as alternativas que o autor considera as mais promissoras para atingir o objetivo pretendido. São selecionadas as melhores opções que contribuem para a redução das emissões de gases, entre as medidas tecnológicas, operacionais e de dimensionamento de frota. Algumas destas alternativas podem ser aplicadas aos navios existentes, enquanto que outras só podem ser aplicadas no projeto de navios novos. / The shipping depends on the energy of oil products, which produce emissions of CO2, SOX, NOX and particulate matter. Today, the water transport accounts for approximately 4.5% of carbon emissions, 4% of sulfur oxides emissions and 7% of nitrogen oxide emissions. If the expansion of this mode of transport is maintained in the coming years, as has been predicted, its participation in the emission of these types of pollutants must increase, and certainly there will be pressure from society for introducing measures to contain its increase. It can be argued that pollutants generated by the Maritime Transport are the result of deficiency in the design of ships and theirs systems, deficient operational management, and even the absence of more stringent regulatory measures. The study focuses on the study of these two points. The first refers to the development of Ship design and propulsion plant with a view to reducing energy consumption. This implies changes in design and propulsion systems, making best use of available technology, as well as the evaluation of viability in the use of sources of alternative energy. The second point refers to the process of operational management, with emphasis on reducing of emissions. Practical examples are examined to support and benefit the reductions of emissions, for example, the reduction of ship speed. Finally is exposed the alternatives that the author considers the most promising to achieve the desired goal. The best options are selected to reducing greenhouse gas emissions between technological measures, operational and fleet sizing. Some of these alternatives can be applied to existing ships, while others may only be applied in the design of new ships.
34

An experimental study of ethanol-diesel dual-fuel combustion for high efficiency and clean heavy-duty engines

Bernardes Pedrozo, Vinícius January 2017 (has links)
Higher atmospheric concentration of greenhouse gases (GHG) such as carbon dioxide and methane has contributed to an increase in Earth's mean surface air temperature and caused climate changes. This largely reflects the increase in global energy consumption, which is heavily dependent on oil, natural gas, and coal. If not controlled, the combustion of these fossil fuels can also produce high levels of nitrogen oxides (NOx) and soot emissions, which adversely affect the air quality. New and extremely challenging fuel efficiency and exhaust emissions regulations are driving the development and optimisation of powertrain technologies as well as the use of low carbon fuels to cost-effectively meet stringent requirements and minimise the transport sector's GHG emissions. In this framework, the dual-fuel combustion has been shown as an effective means to maximise the utilisation of renewable liquid fuels such as ethanol in conventional diesel engines while reducing the levels of NOx and soot emissions. This research has developed strategies to optimise the use of ethanol as a substitute for diesel fuel and improve the effectiveness of dual-fuel combustion in terms of emissions, efficiency, and engine operational cost. Experimental investigations were performed on a single cylinder heavy-duty diesel engine equipped with a high pressure common rail injection system, cooled external exhaust gas recirculation, and a variable valve actuation system. A port fuel injection system was designed and installed, enabling dual-fuel operation with ethanol energy fractions up to 0.83. At low engine loads, in-cylinder control strategies such as the use of a higher residual gas fraction via an intake valve re-opening increased the combustion efficiency (from 87.7% to 95.9%) and the exhaust gas temperature (from 468 K to 531 K). A trade-off between operational cost and NOx reduction capability was assessed at medium loads, where the dual-fuel engine performance was less likely to be affected by combustion inefficiencies and in-cylinder pressure limitations. At high load conditions, a Miller cycle strategy via late intake valve closing decreased the in-cylinder gas temperature during the compression stroke, delaying the autoignition of the ethanol fuel and reducing the levels of in-cylinder pressure rise rate. This allowed for the use of high ethanol energy fractions of up to 0.79. Finally, the overall benefits and limitations of optimised ethanol-diesel dual-fuel combustion were compared against those of conventional diesel combustion. Higher net indicated efficiency (by up to 4.4%) combined with reductions in NOx (by up to 90%) and GHG (by up to 57%) emissions can help generate a viable business case of dual-fuel combustion as a technology for future high efficiency and clean heavy-duty engines.
35

Cobenefits of Global and Domestic Greenhouse Gas Emissions for Air Quality and Human Health

West, Jason, Zhang, Yuqiang, Smith, Steven, Silva, Raquel, Bowden, Jared, Naik, Vaishali, Li, Ying, Gilfillan, Dennis, Adelman, Zachariah, Fry, Meredith, Anenberg, Susan, Horowitz, Larry, Lamarque, Jean-Francois 01 April 2017 (has links)
Abstract available in the Lancet.
36

Co-Benefits of Global and Domestic Greenhouse Gas Emissions for Air Quality and Human Health

West, Jason, Zhang, Yuquiang, Smith, Steven, Silva, Raquel, Bowden, Jared, Naik, Vaishali, Li, Ying, Gilfillan, Dennis, Adelman, Zachariah, Fry, Meredith, Anenberg, Susan, Horowitz, Larry, Lamarque, Jean-Francois 01 October 2017 (has links)
No description available.
37

City of San Luis Obispo: Community and Municipal Operations 2005 Baseline Greenhouse Gas Emissions Inventory

Chiapella, Geoffrey M. 01 March 2010 (has links)
The passage of AB 32 in 2006 initiated the need for city planners in California to consider the quantification of greenhouse gas emissions at the community level in order to develop policies and programs to reduce emissions in the future. Although local jurisdictions are not required to quantify and report emissions at this time, the AB 32 Climate Change Scoping Plan recommended a reduction goal for local governments of 15 percent below today’s levels by 2020 to ensure consistent reduction goals at the state and local levels. ICLEI-Local Governments for Sustainability initiated the Cities for Climate Protection (CCP) campaign in 1993, which provides a framework for local governments to develop a baseline emissions inventory and identify reduction measures as part of a climate action plan. This inventory is developed under the framework of the CCP campaign. A review of the current practice of local greenhouse gas emissions inventories in California identified significant consistencies across jurisdictions in the overall framework of community and municipal emissions inventories– due largely to the framework provided by the CCP campaign. However, data sources used and methods of measurement vary greatly among local inventories, which limit the ability to compare results. This highlights the need for a standard reporting protocol for community inventories. This baseline emissions inventory document provides the technical information necessary for the city to set reduction goals and facilitates the development of the climate action plan outlining policies and programs that when implemented would reach those goals.
38

THE REGIONAL GREENHOUSE GAS INITIATIVE AND U.S. ENERGY MARKETS

Lee, Kangil 01 May 2014 (has links)
The dynamic mutual relationship between the Regional Greenhouse Gas Initiative (RGGI) carbon permit price and energy prices in the U.S. is examined. Results show that the RGGI and electricity markets are not closely linked, although the carbon permit price is usually closely interrelated with energy prices. The loose relationship between the RGGI and electricity markets can be explained by the recent low carbon credit demand which stems from the low greenhouse gas (GHG) emissions existent in the particular area covered by the RGGI. The low GHG emissions result from fuel switching due to recent low natural gas prices. Unlike the European Union Emissions Trading Scheme, natural gas is the key driver of the RGGI system.
39

An integrated approach to modelling urban water systems

Flower, David Jonathan Mark January 2009 (has links)
The energy consumption and greenhouse gas (GHG) emissions associated with urban water systems have come under scrutiny in recent times, as a result of increasing interest in climate change, to which urban water systems are particularly vulnerable. The approach most commonly taken previously to modelling these results has been to consider various urban water system components in great detail, but in isolation from the rest of the system. This piecewise approach is suboptimal, since it systematically fails to reveal the relative importance of the energy consumption and GHG emissions associated with each system component in the context of the entire urban water system. Hence, it was determined that a new approach to modelling the energy consumption and GHG emissions associated with urban water systems was necessary. It was further determined that the value derived from such a model would be greatly enhanced if it could also model the water consumption and wastewater generation associated with each system component, such that integrated policies could be developed, aimed at minimising water consumption, wastewater generation, energy consumption and GHG emissions concurrently. Hence, the following research question was posed: How should the relationships between the water consumption, wastewater generation, energy consumption and GHG emissions associated with the operation of urban water systems be modelled such that the impact of various changes to the system configuration made at different spatial scales can be determined within the context of the entire system? In this research project, life cycle assessment ideas were employed to develop such a new modelling methodology. Initially, the approach was developed at the building-scale, such that the end uses of water present in a selected building and any associated appliances could be modelled, along with the fraction of the citywide water supply and wastewater systems directly associated with providing services to that building. This vast breadth of scope was delivered by considering only the operational life cycle stage of each urban water system component, excluding both the pre- and post-operational life cycle stages of the associated infrastructure. The value of this pilot model was illustrated by several case studies, focused on residential buildings connected to the centralised water supply and wastewater systems in Melbourne, Australia. Later, the approach was extended to the city-scale by using probabilistic distributions of each input parameter, such that all of the end uses of water present in a city, and all of the associated building-scale appliances could be modelled, along with the associated complete water supply and wastewater systems. The value of this city-scale model was illustrated by applying it to model a hypothetical case study city, resembling Melbourne, Australia in many ways. Due to a lack of data, this application was limited to the residential sector of the case study city, along with the fraction of the citywide water supply and wastewater systems directly associated with providing services to that sector. The results generated by the pilot and city-scale models showed that the new modelling methodology could be employed at a wide range of scales to assess the relative importance of each modelled urban water system component in terms of the specified results. Importantly, the high resolution of those results enabled the identification of the underlying causes of the relative importance of each urban water system component, such that efficient and effective approaches to reducing each result for each system component could be developed. Interestingly, for the specific case studies investigated, it was revealed that some commonly neglected system components were actually extremely important, such as domestic hot water services, a trend found to be largely driven by hot water consumption in showers.
40

Classification Of Ethanol Consumers and Willingness to Pay for Reductions in Greenhouse Gas Emissions Through Purchases of E85

Marra, Adrienne Elizabeth 01 August 2010 (has links)
In recent years, the issues of energy dependency and renewable energy options have gained recognition with not only policy-makers but also mainstream consumers. Understanding consumer beliefs and preferences related to these issues is therefore relevant as innovative renewable energy markets have the potential to change conventional consumer purchasing decisions. This paper investigates the beliefs and behaviors of U.S. consumers related to E85 ethanol from corn and cellulosic feedstocks. Four distinct market segments are created so that the ethanol market can be investigated more in-depth. Overall familiarity with ethanol as an alternative fuel is high; however, individual segments vary on beliefs related to corn and cellulosic ethanol, purchasing Flex-Fuel Vehicles, general concern for the environment, and many other factors. In order to successfully market ethanol to a diverse market, the preferences, beliefs and behaviors of these four distinct segments should be taken into account. While environmental concern has waxed and waned over time, issues like as climate change have come to the forefront of both domestic and international discussion and policy. The role of greenhouse gas emissions in contributing to climate change has been acknowledged. As a major source of emissions, transportation fuels are an obvious source of potential reductions in greenhouse gas emissions. This study segments consumers into four distinct market segments and uses a contingent choice method to determine willingness to pay for reductions in greenhouse gas emissions through purchases of E85 ethanol blends. Overall, willingness to pay is estimated at about 0.18 cents per gallon for each percentage in emissions reductions when compared with gasoline containing no ethanol (E0). Willingness to pay for emissions reductions varies in significance and degree across the four market segments. The diversity between the four segments implies that marketing plans should take into account the heterogeneity of consumers and make efforts to account for their varied needs and preferences.

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