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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.
111

Avaliação dos indicadores de energia e emissões de GEE da gasolina e óleo diesel no Brasil através da análise de insumo - produto : Evaluation of energy and GHG emissions indicators of gasoline and diesel oil in Brazil by the input - output analysis / Evaluation of energy and GHG emissions indicators of gasoline and diesel oil in Brazil by the input - output analysis

Canto, Simone Tatiane do, 1981- 24 August 2018 (has links)
Orientadores: Marcelo Pereira da Cunha, Joaquim Eugênio Abel Seabra / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-24T19:54:08Z (GMT). No. of bitstreams: 1 Canto_SimoneTatianedo_M.pdf: 1446988 bytes, checksum: 3c884c3df852de562463eee9e45e87b2 (MD5) Previous issue date: 2014 / Resumo: Este trabalho tem como objetivo avaliar os indicadores de energia e emissões de gases de efeito estufa (GEE) na cadeia produtiva da gasolina e do óleo diesel mineral no Brasil, com uso do modelo de insumo-produto monetário e híbrido, de modo a realizar, também, uma comparação entre os seus resultados. O ano base utilizado foi de 2009, ano mais recente possível de estimar a matriz de insumo-produto a partir dos dados divulgados pelo Instituto Brasileiro de Geografia e Estatística (IBGE). Os modelos (monetário e híbrido) contêm 25 setores e 114 produtos; a técnica permite que sejam computados todos os efeitos diretos e indiretos envolvidos na cadeia produtiva dos setores avaliados. A base de dados usada consistiu, basicamente, nas tabelas de recursos e usos do IBGE (relativas ao ano de 2009), bem como na matriz consolidada relativa aos setores e produtos energéticos (também de 2009) do Balanço Energético Nacional (BEN), divulgado pela Empresa de Pesquisa Energética (EPE). Os resultados obtidos com os dois modelos foram muito próximos, tanto para a gasolina quanto para o óleo diesel; em geral, os efeitos indiretos capturados no modelo híbrido foram um pouco maiores dado o maior encadeamento entre os setores energéticos quando as transações setorias entre estas atividades são computadas em unidades físicas. Com o uso do modelo híbrido, os principais resultados obtidos são de 1,201 ktep e 1,202 ktep de energia incorporados em cada 1 ktep de gasolina e óleo diesel, respectivamente; com relação às emissões de GEE, os indicadores encontrados são de 75,32 gCO2eq/MJ para a gasolina e 86,91 gCO2eq/MJ para o óleo diesel / Abstract: The goal of this study is to evaluate energy and GHG emissions indicators for gasoline and diesel oil in Brazil; the methodology chosen was the Input-Output (IO) Analysis. For this purpose, an economic IO model and a hybrid IO model were made to provide a comparison between them. The analysis considers 2009 as base year, because this is the most recent year which is possible to estimate the Brazilian input-output matrix from official data when the project started. Both models (economic and hybrid) have 25 sectors and 114 commodities; the approach allows all direct and indirect effects through production chain to be estimated. The main data collected and used to build the models were the use and make matrices (provided by The Brazilian Institute of Geography and Statistics ¿ IBGE) and the consolidated matrix with energy flows for primary and secondary energy sources (provided by The Brazilian Energy Research Company ¿ EPE). The results obtained with both models are very similar, considering gasoline as well as diesel oil; in general, the indirect effects captured by the hybrid model are a little bit higher due to the stronger linkage among the energy sectors when the transactions through these activities are accounted in physic (energy) units. From hybrid model, the main results are 1,201 toe and 1,202 toe embodied energy for 1 toe of gasoline and diesel oil, respectively; with respect to GHG emissions, the indicators are 75.32 gCO2eq/MJ to gasoline and 86.91 gCO2eq/MJ to diesel oil / Mestrado / Planejamento de Sistemas Energeticos / Mestra em Planejamento de Sistemas Energéticos
112

Destruição criativa e progresso técnico agrícola = avaliação dos impactos econômicos dos inoculantes na cultura da soja / Creative destruction agricultural and technical progress : assessing the economic impacts of inoculants in soybean

Silva Junior, Jaim José da, 1983- 20 August 2018 (has links)
Orientador: José Maria Ferreira Jardim da Silveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Economia / Made available in DSpace on 2018-08-20T09:07:38Z (GMT). No. of bitstreams: 1 SilvaJunior_JaimJoseda_M.pdf: 2525719 bytes, checksum: d38aa205a46d664074614f1c0f151298 (MD5) Previous issue date: 2012 / Resumo: O objetivo geral deste estudo é discutir a inserção da biotecnologia moderna no sistema de produção agrícola, com foco na nutrição vegetal. Nas lavouras brasileiras de soja, a tecnologia da inoculação é capaz de suprir toda a demanda das plantas por nitrogênio através da fixação biológica do nutriente. Com isso, o uso dos inoculantes permite a substituição integral dos fertilizantes nitrogenados no cultivo da soja no Brasil e constitui um processo de destruição criativa. Com intuito de avaliar de forma empírica o impacto econômico deste processo é desenvolvido um modelo insumo produto a partir da matriz insumo produto da economia brasileira do ano de 2006. A despeito da fixação biológica de nitrogênio, o uso dos inoculantes resulta também no enriquecimento da matéria orgânica do solo, em melhorias no padrão de germinação das sementes, em maior adsorção de nutrientes e no controle de estresses hídricos e térmicos do solo. Em conjunto, tais fatores possibilitam a prática de atividades agrícolas mais sustentáveis, sem comprometer o nível de produção. Porém, não são capazes de impulsionar a difusão dos inoculantes. A incorporação destes benefícios proporcionados pela inoculação ao sistema agrícola requer a construção de mecanismos de avaliação dos impactos dos inoculantes que extrapolem o âmbito dos mecanismos de mercado. Para isso, com base nas abordagens sistêmicas da inovação, este trabalho propõe ações que visam o fortalecimento da trajetória tecnológica dos inoculantes. Em linha com os objetivos deste estudo, a institucionalização de políticas de incentivo à difusão da inoculação constitui uma "porta de saída" para os esforços das organizações públicas de pesquisa e desenvolvimento agrícola e, aumentam as possibilidades de inovação em demais produtos biotecnológicos via o acúmulo de conhecimento nesta área / Abstract: The aim of this thesis is to discuss the insertion of modern biotechnology in the agriculture production system, in particular the plant nutrition. In the Brazilian soybean cultivation, the inoculation technology can supply all the nitrogen that plants need via the biological fixation of nutrients. Thus, the inoculation can replaces all the nitrogen fertilizers in soybean production representing a process of creative destruction. Seeking to empirically assess the economic impact of this process, an input-output model using the data from input-output matrix for the Brazil economy in 2006, is developed. In spite of nitrogen biological fixation, the inoculation also results in soil organic matter enrichment, better patterns of seed germination, great nutrients absorption and control of soil hydric and temperature stresses.Jointly, these factors contribute for more sustainable agricultures practices, without decreasing the production output. However, they cannot boost the diffusion of inoculation technology. To agriculture benefits from the adoption of inoculation technology it is necessary to build an evaluation mechanism that goes beyond the market mechanisms. Based on the systemic approaches innovation, this thesis recommends policies for strengthening the inoculation technology trajectory. In accordance with the proposal of this study, the institutionalization of policies that incentive the diffusion of inoculation technology represent a "way" to transform the efforts of public Research and Development centers in new products and process for agriculture. Additionally, it also increases the chance of innovation for other biotechnology products and processes via the learning by doing process / Mestrado / Ciências Economicas / Mestre em Ciências Econômicas
113

ON EFFICIENT AUTOMATED METHODS FOR SIMULATION OUTPUT DATA ANALYSIS

Brozovic, Martin January 2014 (has links)
With the increase in computing power and software engineering in the past years computer based stochastic discrete-event simulations have become very commonly used tool to evaluate performance of various, complex stochastic systems (such as telecommunication networks). It is used if analytical methods are too complex to solve, or cannot be used at all. Stochastic simulation has also become a tool, which is often used instead of experimentation in order to save money and time by the researchers. In this thesis, we focus on the statistical correctness of the final estimated results in the context of steady-state simulations performed for the mean analysis of performance measures of stable stochastic processes. Due to various approximations the final experimental coverage can differ greatly from the assumed theoretical level, where the final confidence intervals cover the theoretical mean at much lower frequency than it was expected by the preset theoretical confidence level. We present the results of coverage analysis for the methods of dynamic partially-overlapping batch means, spectral analysis and mean squared error optimal dynamic partially-overlapping batch means. The results show that the variants of dynamic partially-overlapping batch means, that we propose as their modification under Akaroa2, perform acceptably well for the queueing processes, but perform very badly for auto-regressive process. We compare the results of modified mean squared error optimal dynamic partially-overlapping batch means method to the spectral analysis and show that the methods perform equally well. / +420 723 771 283
114

Managing human-induced material use : adding cyclic inter-sectoral flows to Physical Input-Output Tables to analyse the environmental impact of economic activity

Altimiras-Martin, Aleix January 2016 (has links)
Current human activity is degrading the environment and depleting biotic and abiotic resources at unheard-of rates, inducing global environmental change and jeopardising the development of humankind. The structure of human activity determines which resources are extracted, how they are transformed and where and how they are emitted back to the environment. Thus, the structure of human activity ultimately determines the human-Earth System interaction and human-induced environmental degradation. Several theories and empirical findings suggest that a cyclic structure would lower the resource requirements and emissions of the economic system, decoupling production and consumption from their environmental impacts. However, the cyclic structure has not been fully characterised nor related to the resource requirements or emission generation estimates of environmental impacts as calculated through models representing the physical structure of the economic system. This thesis is interested in developing tools to analyse the physical structure of the economic system and, ultimately, to develop a method to identify its cyclic structure and relate it to the environmental impact induced by economic activity. Using this new knowledge, it might be possible to reduce the environmental impact of the economy by altering its physical structure. In chapter 3, the different methods to calculate the emissions and resources associated to a given final demand of physical input-output tables are reviewed because they gather different results; it is argued that only two are valid. Surprisingly, these two methods reveal different physical structures; these are explored using a backward linkage analysis and their differences explained. It is found that only one method is appropriate to analyse the physical structure of the economic system and this method is in fact a new input-output model capable of tracing by-products as final outputs. Also, since traditional input-output structural analyses provide aggregate measures, a visual representation of input-output tables enabling researchers to perform disaggregated structural analyses and identify intersectoral patterns is developed. In chapter 4, a method to derive the full cyclic structure of the economic system is developed using network analysis within the Input-Output framework; it identifies the intersectoral cycles and the resources and emissions associated to cycling. It is shown that cyclic flows maximise the system throughput but lower the resource efficiency of the system vis-à-vis the system outputs. It is demonstrated that 1) the complete structure is composed of a cyclic-acyclic and a direct-indirect sub-structure, challenging the common understanding of the functioning of the structure, and 2) cycling is composed of pre-consumer cycling, post-consumer cycling, re-cycling and trans-cycling. In chapter 5, a set of indicators are developed to capture the weight and emissions associated to each sub-structure and the sub-structures are related to the economy's resource efficiency and emissions. In chapter 6, it is illustrated how to use the concepts, indicators and methods developed in previous chapters to identify strategies to improve the resource efficiency of the economy by altering its structure. Finally, in chapter 7, it is suggested to refine the definition of recycling to integrate the different systemic effects of pre-consumer and post-consumer cycling and it is argued that the ideal structure of a circular, close-loop economy should minimise its pre-consumer cycling in favour of more efficient acyclic flows while maximising its post-consumer cycling.
115

THE COMPETITIVE POSITION OF TURKEY WITH RESPECT TO THE EU AND CHINA: AN INSTITUTIONAL AND INPUT-OUTPUT ANALYSIS / EUと中国に対するトルコの競争的地位:制度的分析と産業連関分析

Emre, Ünal 23 September 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(経済学) / 甲第19950号 / 経博第537号 / 新制||経||278(附属図書館) / 33046 / 京都大学大学院経済学研究科経済学専攻 / (主査)教授 宇仁 宏幸, 准教授 矢野 剛, 准教授 COLPAN Meziyet Asli / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DGAM
116

Liens inter-industriels et connexions inter-urbaines dans trois agglomerations importantes du Québec

Robin, Roland. January 1975 (has links)
No description available.
117

Life Cycle Sustainability Assessment Framework For The U.S. Built Environment

Kucukvar, Murat 01 January 2013 (has links)
The overall goals of this dissertation are to investigate the sustainability of the built environment, holistically, by assessing its Triple Bottom Line (TBL): environmental, economic, and social impacts, as well as propose cost-effective, socially acceptable, and environmentally benign policies using several decision support models. This research is anticipated to transform life cycle assessment (LCA) of the built environment by using a TBL framework, integrated with economic input-output analysis, simulation, and multicriteria optimization tools. The major objectives of the outlined research are to (1) build a system-based TBL sustainability assessment framework for the sustainable built environment, by (a) advancing a national TBL-LCA model which is not available for the United States of America; (b) extending the integrated sustainability framework through environmental, economic, and social sustainability indicators; and (2) develop a systembased analysis toolbox for sustainable decisions including Monte Carlo simulation and multi-criteria compromise programming. When analyzing the total sustainability impacts by each U.S. construction sector, “Residential Permanent Single and Multi-Family Structures" and "Other Non-residential Structures" are found to have the highest environmental, economic, and social impacts compared to other construction sectors. The analysis results also show that indirect suppliers of construction sectors have the largest sustainability impacts compared to onsite activities. For example, for all U.S. construction sectors, on-site construction processes are found to be responsible for less than 5 % of total water consumption, whereas about 95 iv % of total water use can be attributed to indirect suppliers. In addition, Scope 3 emissions are responsible for the highest carbon emissions compared to Scope 1 and 2. Therefore, using narrowly defined system boundaries by ignoring supply chain-related impacts can result in underestimation of TBL sustainability impacts of the U.S. construction industry. Residential buildings have higher shares in the most of the sustainability impact categories compared to other construction sectors. Analysis results revealed that construction phase, electricity use, and commuting played important role in much of the sustainability impact categories. Natural gas and electricity consumption accounted for 72% and 78% of the total energy consumed in the U.S. residential buildings. Also, the electricity use was the most dominant component of the environmental impacts with more than 50% of greenhouse gases emitted and energy used through all life stages. Furthermore, electricity generation was responsible for 60% of the total water withdrawal of residential buildings, which was even greater than the direct water consumption in residential buildings. In addition, construction phase had the largest share in income category with 60% of the total income generated through residential building’s life cycle. Residential construction sector and its supply chain were responsible for 36% of the import, 40% of the gross operating surplus, and 50% of the gross domestic product. The most sensitive parameters were construction activities and its multiplier in most the sustainability impact categories. v In addition, several emerging pavement types are analyzed using a hybrid TBL-LCA framework. Warm-mix Asphalts (WMAs) did not perform better in terms of environmental impacts compared to Hot-mix Asphalt (HMA). Asphamin® WMA was found to have the highest environmental and socio-economic impacts compared to other pavement types. Material extractions and processing phase had the highest contribution to all environmental impact indicators that shows the importance of cleaner production strategies for pavement materials. Based on stochastic compromise programming results, in a balanced weighting situation, Sasobit® WMA had the highest percentage of allocation (61%), while only socio-economic aspects matter, Asphamin® WMA had the largest share (57%) among the WMA and HMA mixtures. The optimization results also supported the significance of an increased WMA use in the United States for sustainable pavement construction. Consequently, the outcomes of this dissertation will advance the state of the art in built environment sustainability research by investigating novel efficient methodologies capable of offering optimized policy recommendations by taking the TBL impacts of supply chain into account. It is expected that the results of this research would facilitate better sustainability decisions in the adoption of system-based TBL thinking in the construction field.
118

Achieving carbon emission reduction by efficient re-allocation of production : A product-by-industry analysis of the technical coefficients of Sweden 2016

Hagberg, Loke January 2023 (has links)
The Paris Agreement has stipulated global lowering of carbon emission to reach the 1.5°C target by 2030. The Intergovernmental Panel on Climate Change has suggested several scenarios with rapid innovation and downscaling of energy usage. Against this background, this thesis analyzes the productive capacity of Sweden to reach the corresponding carbon emission target. A product-byindustry input-output-model of the economy to study different re-allocations of production is used. The effect of these re-allocations on the output as well as carbon dioxide emissions from domestic production are considered. Linear optimization is used to achieve efficient re-allocations. Two scenarios are considered: one called the “basic case”, and one called the “efficient export case”. The basic case uniformly rescales the output. The efficient export case internalizes the export and allows it to be uniformly rescaled by the optimization up to trade balance as well. The data is from 2016 as it is the latest data with the necessary information. The result for the basic case shows that the 1.5°C target in 2016 can be reached without downscaling the output. The total employment shrinks by 2%, while some sectors of the economy are significantly changed. The result of the efficient export case has a similar result while total employment shrinks by 11%. The basic case releases 2% less than the reported carbon emissions, and the efficient export case 24% less where the efficient export case downscales the gross domestic product with 13%. The dynamics of innovation, negative impacts on production, and population growth are not accounted for in these estimates. Further studies need to internalize more constraints and develop more detailed models to provide more accurate policy guidance.
119

Advances in simulation: validity and efficiency

Lee, Judy S. 08 June 2015 (has links)
In this thesis, we present and analyze three algorithms that are designed to make computer simulation more efficient, valid, and/or applicable. The first algorithm uses simulation cloning to enhance efficiency in transient simulation. Traditional simulation cloning is a technique that shares some parts of the simulation results when simulating different scenarios. We apply this idea to transient simulation, where multiple replications are required to achieve statistical validity. Computational savings are achieved by sharing some parts of the simulation results among several replications. We improve the algorithm by inducing negative correlation to compensate for the (undesirable) positive correlation introduced by sharing some parts of the simulation. Then we identify how many replications should share the same data, and provide numerical results to analyze the performance of our approach. The second algorithm chooses a set of best systems when there are multiple candidate systems and multiple objectives. We provide three different formulations of correct selection of the Pareto optimal set, where a system is Pareto optimal if it is not inferior in all objectives compared to other competing systems. Then we present our Pareto selection algorithm and prove its validity for all three formulations. Finally, we provide numerical results aimed at understanding how well our algorithm performs in various settings. Finally, we discuss the estimation of input distributions when theoretical distributions do not provide a good fit to existing data. Our approach is to use a quasi-empirical distribution, which is a mixture of an empirical distribution and a distribution for the right tail. We describe an existing approach that involves an exponential tail distribution, and adapt the approach to incorporate a Pareto tail distribution and to use a different cutoff point between the empirical and tail distributions. Then, to measure the impact, we simulate a stable M/G/1 queue with a known inter-arrival and unknown service time distributions, and estimate the mean and tail probabilities of the waiting time in queue using the different approaches. The results suggest that if we know that the system is stable, and suspect that the tail of the service time distribution is not exponential, then a quasi-empirical distribution with a Pareto tail works well, but with a lower bound imposed on the tail index.
120

Využiteľnosť input-output analýzy na hodnotenie fiškálnej politiky / The Strengths and Limitations of Input-Output Analysis in Evaluating Fiscal Policy

Líšková, Lenka January 2015 (has links)
"The Strengths and Limitations of Input-Output Analysis in Evaluating Fiscal Policy" by Bc. Lenka Liskova Abstract: The thesis addresses the recent debates on suitable macroeconomic policy and calls for an alternative evaluation and forecasting method of economic impact, by assessing the applicability of Leontief's input- output model. We concentrate on providing an insight into the entire process of input-output analysis, which yields computation of simple input-output multipliers - output, gross value added and income multi- pliers. Thanks to the ability to capture linkages in the economy, com- puted multipliers are used as a tool to evaluate the effects of vehicle scrappage schemes and ICT infrastructure investment subsidies applied within a sample of diverse developed countries - Australia, Germany, Japan, UK and USA. We also aim to provide a sufficient explanation of the input-output model and a computation manual based on the example of the Leontief open model and calculation of simple multipli- ers. In our research, we numerically evaluate the effects of fiscal stim- ulus measures in the automobile industry and ICT sector and provide their comparison among 5 countries with different industry structures. Most importantly, the thesis provides a suggestion for policy makers to consider applying input-output...

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