Дисертації: "Energy indices"

1

Hanegan, Andrew Aaron. "Industrial energy use indices." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85849.

Анотація:

Energy use index (EUI) is an important measure of energy use which normalizes energy use by dividing by building area. Energy use indices and associated coefficients of variation are computed for major industry categories for electricity and natural gas use in small and medium-sized plants in the U.S. The data is very scattered with the coefficients of variation (CoV) often exceeding the average EUI for an energy type. The combined CoV from all of the industries considered, which accounts for 8,200 plants from all areas of the continental U.S., is 290%. This paper discusses EUIs and their variations based on electricity and natural gas consumption. Data from milder climates appears more scattered than that from colder climates. For example, the ratio of the average of coefficient of variations for all industry types in warm versus cold regions of the U.S. varies from 1.1 to 1.7 depending on the energy sources considered. The large data scatter indicates that predictions of energy use obtained by multiplying standard EUI data by plant area may be inaccurate and are less accurate in warmer than colder climates (warmer and colder are determined by annual average temperature weather data). Data scatter may have several explanations, including climate, plant area accounting, the influence of low cost energy and low cost buildings used in the south of the U.S. This analysis uses electricity and natural gas energy consumption and area data of manufacturing plants available in the U.S. Department of Energy's national Industrial Assessment Center (IAC) database. The data there come from Industrial Assessment Centers which employ university engineering students, faculty and staff to perform energy assessments for small to medium-sized manufacturing plants. The nation-wide IAC program is sponsored by the U.S. Department of Energy. A collection of six general energy saving recommendations were also written with Texas manufacturing plants in mind. These are meant to provide an easily accessible starting point for facilities that wish to reduce costs and energy consumption, and are based on common recommendations from the Texas A&M University IAC program.

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2

Hoi, Loison. "Inflationary spectral indices and potential reconstruction." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99185.

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The Inflationary power spectrum plays an important role in modern cosmology. In this thesis, we studied both the experimental and theoretical aspects of the inflationary spectral index. By exploring the recent WMAP data, we found that the evidence for the running of the spectral index mainly comes from multipoles near l = 40. This fact allows a partial running spectrum to give as good a fit as the WMAP running spectrum. We gave some simple formulae for the inflationary spectral indices based on the Hamilton-Jacobi formulation of inflation. These simple formulae agree with the exact solutions in some special cases. The Hamilton-Jacobi formulation of inflation was also applied to reconstruct inflaton potentials from a given power spectrum. A simple and accurate reconstruction formulation was presented. All analytic potentials giving a constant spectral index are derived, which show that a nearly scale-invariant spectrum can give rise to slow-roll inflation during 60 e-foldings within sub-Planckian inflaton field values and a potential energy V1/4 ~ 1015GeV. Potentials for large running of the spectral index and large tensor-to-scalar ratio were also constructed, which need super-Planckian field values and require that the slow-roll approximation breaks down before reaching 60 e-foldings. We have shown that for the cosmologically interesting scales, a renormalizable potential fits the reconstructed potential for a large running spectrum very well. Our reconstruction formulation also produces a self-consistent tensor spectrum once a scalar spectrum and the tensor-to-scalar ratio are given. Higher order corrections to the slow-roll approximation are also considered. We showed that they can be incorporated straightforwardly into our formulae for spectral indices and the reconstruction formalism.

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3

Annelin, Alice. "Comparing the Volatility of Socially Responsible Investments, Renewable Energy Funds and Conventional Indices." Thesis, Umeå universitet, Företagsekonomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-91029.

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A growing concern among investors for social responsibility in relation to the business world and its effect on the environment, society, and government has increased and therefore different types of stock indices and funds that incorporate socially responsible ideals have been developed. However, a literature review revealed that there does not seem to be much information about the volatility of Green Funds or Socially Responsible Investments (SRI). Volatility is an important part of understanding the financial markets and is used by many to understand asset allocation, risk management, option pricing and many other functions. Therefore, the purpose of this thesis is to investigate the volatility performance of SRIs, REFs and Conventional Indices by using different models CAPM, SR, JA and EGARCH, and monthly and daily data from the US, UK, Japan and Eurozone financial markets to compare results. This thesis has been conducted by following an objective ontological and positivist epistemological position, because the data used for analysis in this thesis is independent from the author and has studied what actually exists, not what the author seeks to interpret. The research approach is functionalist, because this thesis sought to explain how the investments function in relation to volatility comparisons in different financial markets and if this volatility can be predicted through a framework of rules designed by previous researchers. The design is a deductive study of quantitative, longitudinal, secondary data, because hypotheses are derived from theory to test the volatility of time series data between the year 2007 and 2012 through empirical evidence. Statistical evidence was found to suggest that the EGARCH model for volatility measurement is the best fit to model volatility and daily data can give more information and better consistency between results. SRIs were found to be less volatile than CIs in all financial markets; REFs were found more volatile than CIs in the US and Eurozone markets but not in the UK and Japan markets; REFs were found to be more volatile than SRIs in all markets except the UK; REFs were also found to be more volatile than SRIs and CIs during a recession in all markets except the UK. Evidence also indicated that the correlations between REFs and SRIs in the US and Eurozone were significant, but not significant in the UK and Japan market samples. The correlations were low between the UK and Japan SRIs, Japan and Eurozone SRIs and Japan SRI and Eurozone REF, which suggest that an investor may consider to diversify between these investments. However, all other statistically significant correlations between financial markets were high and could consequentially deliver poor long term investment performance.

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4

Adderly, Shawn. "Reviewing Power Outage Trends, Electric Reliability Indices and Smart Grid Funding." ScholarWorks @ UVM, 2016. http://scholarworks.uvm.edu/graddis/531.

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As our electric power distribution infrastructure has aged, considerable investment has been applied to modernizing the electrical power grid through weatherization and in deployment of real-time monitoring systems. A key question is whether or not these investments are reducing the number and duration of power outages, leading to improved reliability. Statistical methods are applied to analyze electrical disturbance data (from the Department of Energy, DOE) and reliability index data (from state utility public service commission regulators) to detect signs of improvement. The number of installed smart meters provided by several utilities is used to determine whether the number of smart meters correlate with a reduction in outage frequency. Indication emerged that the number of power outages may be decreasing over time. The magnitude of power loss has decreased from 2003 to 2007, and behaves cyclically from 2008 to 2014, with a few outlier points in both groups. The duration also appears to be decreasing between 2003-2014. Large blackout events exceeding 5 GW continue to be rare, and certain power outage events are seasonally dependent. There was a linear relationship between the number of customers and the magnitude of a power outage event. However, no relationship was found between the magnitude of power outages and time to restore power. The frequency of outages maybe decreasing as the number of installed smart meters has increased. Recommendations for inclusion of additional metrics, changes to formatting and semantics of datasets currently provided by federal and state regulators are made to help aid researchers in performing more effective analysis. Confounding variables and lack of information that has made the analysis diffcult is also discussed.

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5

Yokoyama, Yoshihiro. "Postmortem Changes in High-Energy Phosphate Compounds and Chemical Indices for Assessing Freshness of Fish and Shellfish." Kyoto University, 1995. http://hdl.handle.net/2433/160858.

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Анотація:

本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである
Kyoto University (京都大学)
0048
新制・論文博士
博士(農学)
乙第8893号
論農博第1976号
新制||農||700(附属図書館)
学位論文||H7||N2810(農学部図書室)
UT51-95-D486
(主査)教授坂口守彦, 教授石田祐三郎, 教授田中克
学位規則第4条第2項該当

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6

Тихенко, C. В. "Применение эколого-экономических показателей в управлении и планировании развития топливно-энергетического комплекса". Thesis, Суми, 1993. http://essuir.sumdu.edu.ua/handle/123456789/60660.

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Анотація:

Применение эколого-экономических показателей в управлении и планировании развития топливно-энергетического комплекса
Application of environmental and economic indicators in the management and planning of the development of the fuel and energy complex

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7

Gomes, Leonardo Alonso. "Metodo baseado em logica nebulosa para alocação de geradores distribuidos sob a optica do perfil de tensão." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/258798.

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Анотація:

Orientadores: Carlos Alberto Favarin Murari, Ahda Pionkoski Grilo Pavani
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: Nesta dissertação é proposta uma metodologia baseada em lógica nebulosa para a obtenção de um índice que classifica as barras mais propícias para a instalação de geradores distribuídos em uma rede de distribuição de energia elétrica. A metodologia foi desenvolvida levando em consideração a dificuldade em se manter um perfil de tensão adequado e, dessa forma, tende a contemplar com os maiores valores de índices, as barras nas quais a conexão de geradores tende a melhorar o perfil de tensão da rede. Outro aspecto considerado no desenvolvimento da metodologia foi o de minimizar as perdas de potência ativa na rede elétrica. De forma geral, a obtenção do índice consiste em associar graus de pertinências para as variáveis magnitude da tensão e potência ativa da carga em cada uma das barras e, a partir de regras nebulosas, definir um valor numérico para o índice. Uma das vantagens dessa metodologia é que tais variáveis podem ser classificadas em conjuntos nebulosos, os quais traduzem lingüisticamente os conhecimentos humanos e, assim, pode-se mais facilmente utilizar a experiência humana adquirida na operação de uma rede de distribuição para a definição das regras nebulosas para a obtenção dos índices a serem empregados na alocação dos geradores. E ao ser comparada a técnicas tradicionais de análise, tem-se uma significativa vantagem que consiste em não necessitar de execuções consecutivas de fluxos de potência, sendo necessário apenas a obtenção do estado de operação da rede através de um único fluxo de potência no caso base.
Abstract: This work consists in proposing a methodology based on Fuzzy Logic to obtain an index, which classifies the buses more suitable to install a distributed generator in an electric power distribution system. Themethodologywas developed taking into consideration the difficulty tomaintain a suitable voltage profile in distribution systems, so the methodology results in large, index values for the buses in which the installation of generators results in a more suitable voltage profile. Another aspect included in the methodology is the minimization of the real power losses. Applying a set of fuzzy rules, the index is calculated by setting membership values to the bus 'voltage' and 'load real power'. The advantages of this methodology are that the classification of the variables into fuzzy sets, which allow the linguistic translation of the system operator knowledge and so his experience of operating the system can be employed in the process of allocating distributed generators in the system and when compared to traditional techniques of analysis, does not need of consecutive runs of power flows, it is necessary only to obtain the state operating of the network through only one power flow in base case.
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica

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8

Sonono, Masimba Energy. "Applications of conic finance on the South African financial markets /| by Masimba Energy Sonono." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9206.

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Conic finance is a brand new quantitative finance theory. The thesis is on the applications of conic finance on South African Financial Markets. Conic finance gives a new perspective on the way people should perceive financial markets. Particularly in incomplete markets, where there are non-unique prices and the residual risk is rampant, conic finance plays a crucial role in providing prices that are acceptable at a stress level. The theory assumes that price depends on the direction of trade and there are two prices, one for buying from the market called the ask price and one for selling to the market called the bid price. The bid-ask spread reects the substantial cost of the unhedgeable risk that is present in the market. The hypothesis being considered in this thesis is whether conic finance can reduce the residual risk? Conic finance models bid-ask prices of cashows by applying the theory of acceptability indices to cashows. The theory of acceptability combines elements of arbitrage pricing theory and expected utility theory. Combining the two theories, set of arbitrage opportunities are extended to the set of all opportunities that a wide range of market participants are prepared to accept. The preferences of the market participants are captured by utility functions. The utility functions lead to the concepts of acceptance sets and the associated coherent risk measures. The acceptance sets (market preferences) are modeled using sets of probability measures. The set accepted by all market participants is the intersection of all the sets, which is convex. The size of this set is characterized by an index of acceptabilty. This index of acceptability allows one to speak of cashows acceptable at a level, known as the stress level. The relevant set of probability measures that can value the cashows properly is found through the use of distortion functions. In the first chapter, we introduce the theory of conic finance and build a foundation that leads to the problem and objectives of the thesis. In chapter two, we build on the foundation built in the previous chapter, and we explain in depth the theory of acceptability indices and coherent risk measures. A brief discussion on coherent risk measures is done here since the theory of acceptability indices builds on coherent risk measures. It is also in this chapter, that some new acceptability indices are introduced. In chapter three, focus is shifted to mathematical tools for financial applications. The chapter can be seen as a prerequisite as it bridges the gap from mathematical tools in complete markets to incomplete markets, which is the market that conic finance theory is trying to exploit. As the chapter ends, models used for continuous time modeling and simulations of stochastic processes are presented. In chapter four, the attention is focussed on the numerical methods that are relevant to the thesis. Details on obtaining parameters using the maximum likelihood method and calibrating the parameters to market prices are presented. Next, option pricing by Fourier transform methods is detailed. Finally a discussion on the bid-ask formulas relevant to the thesis is done. Most of the numerical implementations were carried out in Matlab. Chapter five gives an introduction to the world of option trading strategies. Some illustrations are used to try and explain the option trading strategies. Explanations of the possible scenarios at the expiration date for the different option strategies are also included. Chapter six is the appex of the thesis, where results from possible real market scenarios are presented and discussed. Only numerical results were reported on in the thesis. Empirical experiments could not be done due to limitations of availabilty of real market data. The findings from the numerical experiments showed that the spreads from conic finance are reduced. This results in reduced residual risk and reduced low cost of entering into the trading strategies. The thesis ends with formal discussions of the findings in the thesis and some possible directions for further research in chapter seven.
Thesis (MSc (Risk Analysis))--North-West University, Potchefstroom Campus, 2013.

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9

Pomeroy, Stephanie K. "Effect of dietary lysine and genetics on indices of energy and protein metabolism in rainbow trout and alterations in the mitochondrial proteome in broilers fed a lysine-deficient diet." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=6035.

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Анотація:

Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains viii, 89 p. : ill. Includes abstract. Includes bibliographical references (p. 67-73).

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10

Varella, Fabiana Karla de Oliveira Martins. "Estimativa do indice de nacionalização dos sistemas fotovoltaicos no Brasil." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263003.

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Orientadores: Carla Kazue Nakao Cavaliero, Ennio Peres da Silva
Tese (doutorado) -Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: A Lei nº 10.438/02 estabeleceu o Programa de Incentivo às Fontes Alternativas de Energia Elétrica - PROINFA, único programa nacional a estimular as fontes renováveis alternativas, com o intuito de aumentar a participação da energia elétrica produzida por empreendimentos a partir das fontes eólica, pequenas centrais hidrelétricas - PCHs e biomassa no sistema interligado nacional. Posteriormente, o PROINFA foi revisado pela Lei nº 10.762/03 e alterou em sua regulamentação a obrigatoriedade de um índice mínimo de nacionalização de serviços e equipamentos, que em sua primeira etapa passou a corresponder a 60% do custo total da construção dos projetos contemplados. A energia solar fotovoltaica não foi contemplada pelo Programa, e o objetivo desta tese é estimar o índice de nacionalização para cada um dos três sistemas fotovoltaicos selecionados para estudo (sistema de bombeamento de água, sistema de eletrificação rural e sistema conectado à rede elétrica). Para elaboração desse cálculo foi efetuada uma adaptação da metodologia utilizada pelo PROINFA e considerados somente os custos dos principais equipamentos e não dos serviços. Os resultados obtidos permitiram concluir que os sistemas de bombeamento de água e de eletrificação rural são sistemas que 5% e 35%, respectivamente, dos seus equipamentos já são disponibilizados pela indústria nacional. mesmo não ocorre com os sistemas fotovoltaicos conectados à rede elétrica, que atualmente tem 100% dos seus principais equipamentos importados
Abstract: The Law nº 10.438/02 established the Program of Incentives for Alternative Electric Power Sources - PROINFA, which is the only national program aimed to foster alternative renewable energy sources and to increase the share of electric energy production from enterprises based on wind power, small hydropower plants and biomass in the interconnected national power grid. PROINFA was later modified by the Law nº 10.762/03 which revised the regulation imposing a minimum nationalization index of services and equipment that in its first stage corresponded to 60% of the total cost of the selected projects. Solar photovoltaic power was not included in PROINFA and because of that the objective of this thesis is to estimate the nationalization index of each of the following photovoltaic systems selected for the study: water pumping PV system, rural electrification PV system and grid-connected PV system. In order to carry out the calculations, the methodology used at PROINFA was adapted and only the costs of the key equipment, not the services, were considered. The results led to the conclusion that the water pumping and the rural electrification systems are those in which 5% and 35%, respectively, equipment is already made available by the national industry. The same is not verified for the grid-connected PV systems in which 100% of the key equipment is imported
Doutorado
Doutor em Planejamento de Sistemas Energéticos

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11

Camilleri, James. "India's energy security : understanding its strategic condition." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186862.

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This thesis considers India's pursuit of energy security. Defining energy security within traditional parameters of supply, delivery, diversification of fuels and suppliers, and affordable prices; the work considers India's energy security condition by surveying the core energy sectors including coal, oil and gas, hydroelectricity, nuclear power and renewables. India's pursuit of energy security is then disaggregated into domestic and international arenas and both are analysed in turn. Considerable attention is paid to the international dimension where India's quest to acquire energy resources is contextualised within bilateral relations with specific countries. What the proceeding analysis makes clear is that the international arena offers considerable opportunities, but also constraints on, the realisation of greater energy security. Chapter one analyses global trends in the main energy sectors of coal, oil, natural gas, hydroelectricity, nuclear power and renewables. Historically, the fortunes of the global energy sectors have mirrored trends in the global economy. Since 2008, most of the world's major industrialised economies have experienced negative or greatly reduced levels of growth. This is primarily due to the proliferation of vast quantities of debt that have capsized several financial institutions and are adversely affecting the liquidity and solvency of many developed governments. The global energy sectors have also been deeply affected by the economic downturn with access to funds for the development of new infrastructure squeezed. The recent poor economic growth of these countries has further accentuated the downward trend they have experienced in energy consumption. Nevertheless, many parts of the developing world, including India, have only been marginally affected by the global economic downturn and continue to develop rapidly. Consequentially most of the growth in demand for energy is coming from developing countries, particularly India. Although there are slight variations depending on sector, this dual trend of stagnation in the developed world and rapid growth in the developing is one ofthe recurring themes in the global energy markets. It is within this context that the second chapter considers India's energy security condition. Detailed analysis of the coal, oil, gas, hydroelectric and renewable sectors demonstrate succinctly that India is experiencing considerable growing pains. While several challenges are unique to each sector the chapter also identifies several systemic problems, including insufficient supply, rampant demand, a tendency to import.

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12

Murray, Caitlin Lenore. "India's nuclear power program : a study of India's unique approach to nuclear energy." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/41594.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Nuclear Science and Engineering, 2006.
Includes bibliographical references (p. 53-57).
India is in the middle of the biggest expansion of nuclear power in its history, adding 20 GWe in the next 14 years in the form of pressure water reactors and fast breeder reactors. At the same time, the United States is overturning decades of policy in order to resume the export of nuclear materials to India, opening up the possibility of private investors in the Indian nuclear industry for the first time. This is a period of progress and turmoil in India's nuclear power program. This thesis seeks to describe and analyze India's nuclear prospects and to qualitatively assess the system's strengths and weaknesses. Using the inception of the country's nuclear power program as a starting point, this thesis will trace India's nuclear lineage to the present. In the process, it will evaluate what makes the Indian program unique, and why it may not be ideal for India that the United States is finally renewing its offers of a cooperative nuclear alliance.
by Caitlin Lenore Murray.
S.B.

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13

Rajashekaran, Dhruv. "Is Pursuing Nuclear Energy in India's Strategic Interest?" Thesis, Webster University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1526151.

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As a developing country with the second largest population in the world, India's energy needs will continue to grow steadily in the coming decades. A significant proportion of India's oil, coal and natural gas are imported because of a dearth of indigenous energy resources. This creates a situation of energy dependence and is a potential national security issue. As a result, the government is embarking on an ambitious plan to have nuclear power generate 25% of electricity in 2050 – up from 3.7% in 2012. The aim is to be running on thorium fast-breeder reactors, that are currently in development, by that time. India's vast reserves of thorium would mean that this would improve energy security, while also improving access to energy for the large part of its population that remains without it.

However, nuclear energy is controversial. Issues of safety and viability must be addressed adequately if nuclear energy is to be pursued. Civil-society concerns about the displacement of people and the degradation or changes in environment around plants and its consequences must also be appropriately addressed. The aim of this paper is to ascertain if it is indeed in India's strategic interest to invest in nuclear energy. Within a theoretical framework of energy security the paper will seek to identify what changes should be made in the sector to guide and manage the process of expanding nuclear-power generation is also important if prescribing this course of action.

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14

Sales, José Nélio de Sousa. "Efeito da dieta com alta energia nos parâmetros metabólicos, endócrinos e reprodutivos de vacas Bos indicus e Bos taurus." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-10102012-155605/.

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Анотація:

Avaliou-se o efeito da dieta com diferentes níveis de energia [mantença (M) e alta energia (1,7M)] nos parâmetros metabólicos, endócrinos e reprodutivos de vacas não lactantes Bos indicus (14 Gir) e Bos taurus (14 HPB) submetidas aspiração folicular (OPU) seguida de produção in vitro de embriões. Os animais foram distribuídos aleatoriamente de acordo com a raça e a dieta. As doadoras foram mantidas em sistema Tie stall e as dietas foram fornecidas duas vezes ao dia (8:00 e 16:00 h). Os animais receberam dieta M por uhm período de adaptação de 21 dias. Após esse período, os grupos experimentais foram submetidos a nove punções foliculares com intervalos de 14 dias. Para realização da OPU, no D0 as doadoras foram sincronizadas com 2 mg de benzoato de estradiol e um implante auricular de norgestomet. No D5, as OPUs foram realizadas. Não houve interação entre as espécies e níveis de energia na dieta para as variáveis estudadas. Não foram observadas diferenças quali-quantitativa dos oócitos entre as dietas. Porém, houve diferença na quantidade e qualidade oocitária entre as espécies estudadas. Vacas Bos indicus apresentaram maior quantidade de estruturas recuperadas e melhor qualidade oocitária que as doadoras Bos taurus. Semelhantemente aos resultados da qualidade e quantidade oocitária, a produção in vitro de embriões também não diferiu entre as dietas e verificou-se maior produção in vitro de embriões em vacas Bos indicus. No entanto, foi observado que o excesso de energia reduziu a produção in vitro de embriões após 60 dias de fornecimento da dieta somente em vacas Bos indicus. Verificou-se menor abundância de transcritos para os genes IGF2R e HSP70.1 em oócitos de vacas alimentadas com alta energia na dieta. Além disso, observou-se que vacas da raça Gir apresentaram maior abundância de transcritos para os genes GLUT1 e IGF1R. Vacas alimentadas com excesso de energia na dieta apresentaram maiores concentrações séricas e no fluido folicular de glicose e colesterol e maiores níveis de AGNE no líquido folicular. Porém, a concentração de nitrogênio ureico no soro e no fluido folicular foi maior nas vacas que receberam dieta de mantença. Quanto ao grupo genético, observou-se que vacas Bos indicus apresentavam maiores concentrações de glicose, colesterol, AGNE e nitrogênio ureico, tanto no líquido folicular quanto no soro. Além disso, as concentrações de insulina e IGF1 no líquido folicular foram maiores nas vacas do Grupo alta energia Bos indicus . Por fim, observou-se quadro de hiperinsulinemia (Gir [insulina] > 51,9 μUI/ml e HPB [insulina] >17,2 μUI/ml) em 60% das vacas Bos indicus que receberam alta energia na dieta. Conclui-se que o aumento de energia na dieta não interferiu na quantidade e qualidade (avaliada visualmente) de oócitos. No entanto, o excesso de energia reduziu a produção in vitro de embriões em vacas Bos indicus após 60 dias de fornecimento da dieta. Além disso, vacas Bos indicus apresentaram melhor qualidade e maior quantidade de oócitos viáveis e produção in vitro de embriões que as doadoras Bos taurus.
The effect of different energy levels in diet [maintenance (M) and high energy (1.7M)] was evaluated on metabolic, endocrine and reproductive parameters of non lactating Bos indicus (n=14) and Bos taurus (n=14) cows submitted to ultrasound guided ovum pick up (OPU) followed by in vitro embryo production. Cows were randomly assigned, according to their breed and diet. The oocyte donors were housed in Tie Stall System and the diets were given twice daily (8:00 AM e 4:00 PM). During 21 days prior to the beginning of experiment, animals were fed with the maintenance diet for their adaptation. After this period, the experimental groups were submitted to nine OPU procedures, fourteen days apart each. To synchronize the donors, cows received 2mg of estradiol benzoate on day 0 (D0) and one norgestomet auricular implant. The OPU were performed on D5. There were no interaction between breeds and energy level in diet for the evaluated variables. No qualitative or quantitative differences were in oocytes between the two diets. However, there was difference in oocyte number and quality between breeds. Bos indicus cows showed higher number of recovered structures and better oocyte quality when compared to Bos taurus donors. Similar to what was found in oocyte quality and number, the in vitro embryo production also did not differ between diets and it was observed that Bos indicus cows had higher production of embryos. However, we verified that the energy surplus reduced in vitro embryo production in Bos indicus cows after 60 days of high energy diet. It was also possible to observe lower oocytes transcripts abundance for IGF2R and HSP70.1 genes of cows fed with high energy diet. Moreover, Gir cows showed higher transcript abundance for GLUT1 and IGF1R genes. Cows fed with excess of energy in diet presented higher serum and follicular fluid concentrations of glucose and cholesterol and increased NEFA levels in follicular fluid. However, the ureic nitrogen concentration was higher in cows which received maintenance diet. When comparing the two genetic groups, it was observed that Bos indicus cows presented higher concentrations of glucose, cholesterol, NEFA and ureic nitrogen both in follicular fluid and in blood. Furthermore, cows that presented decreased blastocyst rate (high energy - Bos indicus) exhibited high follicular fluid concentrations of insulin and IGF1. Finally, it was observed that 60% of Bos indicus cows fed with high energy diet presented yperinsulinemia (Gir [insulin] > 51.9 μUI/ml and HPB [insulin] >17.2 μUI/ml). In conclusion, increasing energy in diet did not interfere in oocyte number and quality (visual evaluation). However, the energy surplus reduced the in vitro embryo production in Bos indicus cows after 60 days of diet. Moreover, Bos indicus cows showed better oocyte quality, higher number of viable oocytes and increased in vitro embryo production than Bos taurus donors.

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15

Simpson, Lori Allison. "The suitability of coal gasification in India's energy sector." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/38569.

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Анотація:

Thesis (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division, Technology and Policy Program, 2006.
Includes bibliographical references (p. 83-86).
Integrated Gasification Combined Cycle (IGCC), an advanced coal-based power generation technology, may be an important technology to help India meet its future power needs. It has the potential to provide higher generating efficiency, can be adapted to efficiently burn India's high-ash coal, and has the potential to do so with greatly reduced emissions and offers the longer term potential to assist India to manage its C02 emissions. Efficient gasification technology also offers India the potential to produce a variety of fuels, particularly transportation fuels, and chemicals. These potential benefits would be useful in a country that has coal shortages, runs inefficient power plants, and imports the majority of its transportation fuels. Driven by these potential benefits the Central Government-owned power generating equipment manufacturing company (BHEL) is developing a fluid-bed gasifier designed for Indian coals, but has not yet demonstrated it at a size larger than 6 MW. Outside of BHEL, there are many factors holding this technology back. First, the technology is projected to be more expensive than pulverized coal (PC) power generation. In the Indian environment, the capital costs are estimated to be 1.5 times higher, and the levelized cost of electricity is estimated to be 33 % higher than for PC power generation.
(cont.) Further, there are other technology options, such as super-critical pulverized coal technology, which are cheaper, more proven, and can provide immediate higher generating efficiency. The first supercritical PC plant is currently being built in India. To overcome these barriers will take further research and development, as well as demonstration at a commercial scale. This all needs to occur at a greater speed and with a greater urgency than is now apparent. The demonstration and commercialization will require significant subsidies, which may come in different forms. The Central Government may wish to subsidize the technology development for the pollution control benefits that it offers and do so via its linkages to BHEL. Foreign governments and institutions may choose to subsidize the costs for the carbon dioxide reduction credits that it can produce. In the end, the challenges facing IGCC in India are great. The cost and generating efficiency will have to at least rival those for other advanced coal technologies, and coal production and mining policies will have to be effectively enacted to increase the supply of coal available for new coal plants.
by Lori Allison Simpson.
S.M.

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16

Cipriano, Rafael Silva. "Influência da adição de gordura protegida na dieta de novilhas Nelore (Bos taurus indicus) no estabelecimento da puberdade e da ciclicidade pós-parto." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-02092016-155300/.

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O presente trabalho teve como objetivo verificar se o fornecimento de gordura protegida após à desmama interfere no desenvolvimento folicular e na idade à primeira ovulação em novilhas Nelore (Bos taurus indicus). E também se os ácidos graxos de cadeia longa no terço final da gestação interferem no desenvolvimento folicular e antecipa a ciclicidade no período pós-parto de primíparas com escore corporal de 2,5. No primeiro utilizamos 30 novilhas Nelore com peso 167kg, separadas em 3 grupos: Grupo Controle (GC, n=10) recebeu 500g de milho/animal/dia. Grupo Gordura (GG, n=10) recebeu 200g de gordura protegida/animal/dia. Grupo Energia (GE, n=10) recebeu 500g de milho e 200g de Megalac-E®/animal/dia. Foi realizado exame ultrassonográfico dos ovários e colhidas amostras de sangue para quantificação de FSH, LH, leptina e progesterona. Durante o tratamento o peso não variou entre os grupos, o peso vivo aumentou ao longo do tempo (p=0,0001). Após a mudança na dieta, os animais dos grupos que receberam gordura apresentaram menor (p=0,019) número de folículos que os animais do GC. Durante o período dos tratamentos nutricionais o GG apresentou maior (p=0,05) número de picos de LH que o GE e o GC foi intermediário. O GC apresentou maior área de secreção de FSH (p=0,03) quando comparado ao GG e o GE foi intermediário. O GC apresentou maior área de concentração e valor máximo máxima de FSH (p=0,06) aos 14 meses. Dentro de cada grupo, todos apresentaram menor área total de secreção de leptina antes do tratamento comparado ao período pós tratamento. Após o período de tratamento, o GE apresentou maior valor máximo máxima de leptina (p=0,08) que o GC e o GG valor intermediário. A gordura diminuiu o número de folículos, aumentou a freqüência de pulsos de LH, diminuiu a secreção de FSH durante o começo da suplementação. A dieta com a soma das energias diminuiu a área de secreção de LH e aumentou a valor máximo máxima de concentração de leptina. No segundo experimento utilizamos 19 animais, com 24 a 27 meses de idade e peso de 366kg. Os tratamentos nutricionais foram realizados de 50 a 60 dias antes do parto previsto. As novilhas foram divididas em dois grupos: grupo Controle (GC, n=9) sem adição de gordura na ração (250 g de milho/novilha/dia) e grupo Gordura (GG, n=10) com gordura na ração (100g Megalac-E®/novilha/dia). Os animais foram mantidos em um escore corporal de 3,5 no período pré-parto, e diminuíram e foram mantidos com 2,5 até os noventa dias após parto. O GC obteve maior ganho médio diário dos 91 aos 119 dias pós-parto (p=0,011) comparado ao GG.O peso à ovulação foi maior no GC que no GG (p=0,03). O diâmetro do maior folículo não diferiu (p=0,31) entre o GC e GG durante o pós-parto. O diâmetro do segundo maior folículo foi maior no GC (p=0,028) que no GG. Houve um aumento no diâmetro do maior folículo no GC (p=0,05) e uma tendência no GG. Os dois grupos apresentaram aumento na concentração de LH com o passar dos intervalos (GC p<0,0001, GG p=0,0024). Entre o 15° e 30° dia pós-parto foi o período que apresentou menor área total de concentração de LH (p<0,0001) comparado aos demais intervalos dentro de cada grupo (p=0,85). GC e GG tiveram maior valor máximo de LH no intervalo de 75 a 90 dias (p=0,03 e p=0,04) quando comparado com os intervalos de 15 a 30 e de 30 a 45 dias pós-parto (p=0,97). Não houve diferença no peso vivo ao nascimento das bezerras do GC (34,3±2,58kg, p=0,18) comparado as do GG no período pré-parto (31,75±4,62 kg). As bezerras nascidas de vacas do GC obtiveram maior ganho médio diário nos primeiros 30 dias pós-parto (p=0,05) comparadas às bezerras do GG. Não houve diferença no ganho de peso por mamada das bezerras entre os GC e GG no período pós-parto, aos 20 dias (p=0,30), aos 46 dias (p=0,46), aos 81 dias (p=0,63) e aos 108 dias (p=0,66). Animais tratados com gordura no pré-parto apresentam um maior tempo para a primeira ovulação, menor quantidade de folículos secundários, acompanhada de menor peso vivo e menor ganho de peso no final do pós-parto
This study evaluated whether protected fat supply after weaning will interfere on follicular development and age at first ovulation in Nelore heifers (Bos taurus indicus) and if fat in the final third of pregnancy increases the preovulatory follicle diameter and number of follicles, changing the cyclicity in postpartum primiparous with a body score of 2.5. For this two experiments were developed, at first 30 contemporary Nellore heifers with of 167 kg life weight were used. The animals were sorted into 3 groups: Control group (CG, n=10), 500g of corn/animal/day. Fat group (GG, n=10), 200g of Megalac-E®/animal/day. Energy group (EG, n=10), 500g of corn plus 200g Megalac-E®/animal/day. Ovaries ultrasonography was performed to characterize the diameter and number of follicles. Blood samples were collected and radioimmunoassay was performed to quantify LH, FSH, progesterone and leptin. Either during nutritional treatment (p=0.32) or after (p=0.34) there was no difference in life weight between groups, but weight increased over time (p=0.0001). Heifers that received fat had lower (p=0.02) number of follicles than the control group. During nutritional treatments Fat group had higher (p=0.05) number of LH peaks than the Energy group and Control group showed intermediate number of LH peaks. The GC showed greater FSH concentration area (p=0.03) compared to GG and GE was intermediate. The GC had higher FSH concentration area (p=0.06) and maximum valor máximo (p=0.08), than GG and GE had intermediate values at 14 months. All groups exhibited lower leptin total concentration area before compared to after nutritional treatments. After the treatment period, the GE had higher leptin maximum value (p=0.08) than control group and GG intermediate. Fat supply decreased the number of follicles, increased LH pulses frequency, decreased FSH concentration at the supplementation beggining. Energy energy diet anticipated age at puberty, decreased LH concentration area and increased leptin concentration maximum value. For the second experiment 19 animals between 24 and 27 months of age and 366kg live weight were used, fixed time artificial insemination was performed (TAI). The dietary treatments were performed during 60 days before the estimated partum. The heifers were sorted in: Control (CG, n = 9) with no added fat (250 g of corn/heifer/day) and fat group (GG, n = 10) with 100 g Megalac-E®/heifer/day. The animals were maintained in a 3.5 BSC (1 to 5) during pre-partum, and decreased and maintained with 2.5 BSC until 90 days after calving. The GC had a higher average daily weight gain from 91 to 119 days postpartum (p=0.011) compared to GG. The weight at ovulation was higher in GC (p=0.03) than GG. Largest follicle diameter did not differ (p=0.31) between the CG and GG during the postpartum period. Second largest follicle diameter was greater in the GC (p=0.028) than in GG. There was an increase in the largest follicle diameter in CG (p=0.05) and a tendency in GG during the experimental period. Both groups showed an increase in LH concentration over the intervals (p<0.0001; p=0.0024). Between the 15th and 30th day postpartum there was the lowest LH concentration total area (p<0.0001) compared to other intervals within each group. LH maximum value was greater (p=0.03 and p=0.04) between 75 to 90 days compared to 15-30 and 30-45 days postpartum. There was no difference in calves birth weight between GC and GG (p=0.18). Calves born from GC cows had greater average daily weight gain in the first 30 days (p=0.05) than calves from GG. There was no difference in weight gain after 15 min suckling between GC and GG calves at 20, 46 days, 81 and at 108 days. Heifers treated with fat in pre-partum have an increased time to first ovulation, fewer secondary follicles, accompanied by a lower body weight and less weight gain in the end of postpartum

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17

Carvalho, Marina Vieira de. "Efeito do Fornecimento Crônico de Leptina e da Nutrição na Maturação Sexual de Novilhas Zebuínas (Bos taurus indicus)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-23032011-162453/.

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O objetivo deste estudo foi avaliar o fornecimento crônico de leptina recombinante ovina (oLeptina) e do nível de energia da dieta na idade, peso vivo (PV), escore de condição corporal (ECC) e composição corporal à puberdade, assim como avaliar seus efeitos no desenvolvimento dos folículos ovarianos e no consumo de matéria seca (CMS). Foram utilizadas 36 novilhas da raça Nelore, com média de 18 a 20 meses de idade, 276,1 ± 17,9 kg PV e ECC de 4,7 ± 0,46, distribuídas aleatoriamente em três tratamentos: A) Dieta de alta energia; B) Dieta de baixa energia, BL) Dieta de baixa energia com administração subcutânea de oLeptina. Os animais foram alojados de 2 baias coletivas de acordo com a dieta oferecida. As dietas foram formuladas para promover um ganho de peso médio diário (GMD) de 0,3 kg PV/dia e 1,0 kg PV/dia. O controle de consumo foi feito através da pesagem diária das sobras e manutenção dessas entre 5 e 10% do total oferecido. Os animais foram pesados e tiveram o ECC avaliado duas vezes por semana, para acompanhamento do GMD. Foi administrado 12 g de óxido de cromo/animal/dia por deglutição forçada por 10 dias, com coleta de amostras de fezes, dieta e sobras nos últimos 5 dias, para estimativa do consumo individual de MS e energia, através da determinação do cromo nas fezes e do FDNi nas fezes, dietas e sobras. O grupo BL recebeu 4,8 µg de oLeptina/kg PV, via subcutânea, duas vezes ao dia (6:00 e 18:00 horas) por 56 dias, enquanto os grupos A e B receberam 2 ml de solução salina. O diâmetro máximo do folículo dominante (FD) e a presença de corpo lúteo (CL) foram avaliados através de ultrassonografia transretal duas vezes por semana, até o momento da puberdade. No momento da ultrassonografia, foram coletadas amostras de sangue, por punção da veia jugular, para dosagem da concentração sérica de progesterona. A idade à puberdade foi considerada como a idade na primeira detecção de um CL, confirmado como sendo funcional por dosagem de progesterona acima de 1 ng/ml. Após a confirmação da puberdade os animais foram abatidos para estimativa da composição corporal, através da determinação do teor de água em cortes da 9a-10a-11a costelas. O maior teor de energia na dieta reduziu a idade e aumentou o ECC à puberdade (P<0,05). A leptina não teve efeito na idade, PV ou ECC à puberdade (P>0,05). Tanto o maior consumo de energia quanto a leptina aumentaram a velocidade de crescimento e determinaram maior diâmetro médio do FD (P<0,05), entretanto a velocidade de crescimento do FD do grupo BL voltou a diminuir, igualando-se à do grupo BL, após cerca de 30 dias de tratamento, comportando-se de forma quadrática à análise de regressão. O maior consumo de energia determinou maior teor de extrato etéreo e menores teores de proteína, matéria seca e matéria mineral no corpo vazio, além de maior espessura de gordura subcutânea e área de olho de lombo na carcaça (P<0,05). A aplicação de leptina não alterou a composição corporal das novilhas à puberdade (P>0,05). Não houve diferença no CMS (kg MS/dia) entre os grupos, entretanto o grupo A teve menor CMS em % PV, além de maior consumo de energia digestível, metabolizável e líquida para ganho (P<0,05). A leptina não reduziu o CMS das novilhas (P>0,05) tanto em kg MS/dia quanto em % PV. A energia acelera a obtenção da puberdade e altera a composição corporal à puberdade de novilhas zebuínas. A aplicação de leptina não acelerou a obtenção da puberdade de novilhas zebuínas em baixo consumo de energia, mas aumentou temporariamente a taxa de crescimento folicular desses animais.
This study was carried out to evaluate the effects of chronic administration of recombinant ovine leptin (oLeptin) and the energy level of the diet on age, body weight (BW), body condition score (BCS) and body composition at puberty, as well as to evaluate its effects on dominant follicle (DF) development and dry matter (DM) intake. Thirty six Nellore heifers, 18 to 20 months old, with 276.1 ± 17.9 kg BW and BCS of 4.7 ± 0.46 were randomly distributed into three treatments: H) High energy diet; L) Low energy diet; LL) Low energy diet with subcutaneous administration of oLeptin. Heifers were housed in two collective pens according to the diet offered. Diets were formulated to promote an average daily gain (ADG) of 0.3 kg BW/day and 1.0 kg BW/day. Intake was controlled daily by weighting the orts and keeping it between 5 and 10% of the total offered. Heifers were weighed and had their BCS was evaluated twice weekly, in order to control the ADG. Heifers received 12 g of chromic oxide/animal/day by forced swallowing for 10 days, while feces, diet and orts were sampled in the last 5 days, in order to estimate individual DM and energy intake, which was done by feces determination of chromic oxide, and diet and, feces and orts determination of iNDF. The LL group received 4.8 µg oLeptina/kg BW, subcutaneously, twice a day (at 06:00 and 18:00), for 56 days, while H and L groups received 2 ml of saline solution. Maximum DF diameter and presence of corpus luteum (CL) were evaluated twice weekly by transrectal ultrasound, until heifers achieved puberty. At the time of ultrasound evaluation, blood was sampled by jugular venipuncture for serum progesterone determination. Age at puberty was considered as age at first detection of a CL confirmed to be functional by serum progesterone above 1 ng/ml. After puberty confirmation heifers were slaughtered for body composition estimation, which was done by water determination on 9a-10a-11a rib cuts. High energy intake reduced age and enhanced BCS at puberty (P<0.05). Leptin administration did not affect age, BW or BCS at puberty (P>0.05). The high energy intake as well as leptin administration accelerated the DF growth and determined greater DF diameter (P<0.05), however the rate of growth on the LL group decreased after around 30 days of treatment equaling the rate of growth of the L group, and behaving in a quadratic manner at regression analysis. High energy intake enhanced ether extract and lowered protein and minerals proportion on empty body (P<0.05). It also enhanced carcass subcutaneous fat and the longissimus muscle area (P<0.05). Leptin administration did not alter the body composition of heifers at puberty (P>0.05). There was no difference on DM intake (kg DM/day) between groups, however the H group had higher DM intake in terms of % BW, as well as higher intake of digestible, metabolizable and net energy for gain (P<0.05). Leptin did not reduce DM intake neither in terms of kg BW/day nor % BW (P>0.05). Energy intake accelerates the onset of puberty and alters body composition at puberty of zebu heifers. Leptin administration did not accelerate puberty onset of zebu heifers receiving low energy diet, but temporarily enhanced the follicular growth rate of these animals.

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18

Chopra, Dhruv M. "An Assessment of the Use of Coal in India's Energy Future." Scholarship @ Claremont, 2013. http://scholarship.claremont.edu/cmc_theses/601.

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India is the largest democracy in the world and is likely to supersede China with the biggest population in the near future. While India has emerged as one of the fastest growing economies in the world over the last decade, sustaining this rapid growth will be largely dependent upon the extent to which the country is able to meet its rising energy demand. India has been dependent upon coal for its power generation due to its relative abundance and economic sense in comparison to other resources. However, continuing to rely on coal to meet its energy needs is likely to be problematic given the already increasing shortfall between energy demand and supply in addition to issues surrounding the extraction of domestic coal. This thesis will explore these issues, evaluate the extent to which India can continue to rely on coal to meet its energy needs and identify other possible avenues through which the country can meet its rising energy demand in a more sustainable manner economically and environmentally.

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19

Deb, Nikhilendu. "Risk Society, Nuclear Energy, and India's Response to the Fukushima Meltdown." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1430743239.

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20

Mehra, Amaani. "Is India's Push for Renewables a Shove to its Impoverished Communities?" Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/scripps_theses/1335.

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India has ambitious targets to develop extensive renewable energy infrastructure by 2022. These targets are driven by the country’s pressing environmental and demographic concerns. While the development of such infrastructure can have many benefits, the costs of are often disproportionately borne by some of the most impoverished groups due to land acquisition and displacement. Land acquisition often occurs in rural areas, where the majority of the population are farmers or tribal groups. While there are laws to protect the rights of these groups, the effectiveness of these laws is often undermined by state governments that prioritize investment. Looking at the development of solar, wind, and small hydropower, the various impacts on rural communities are evident. Without adequate compensation for the loss of land and the suffering caused by displacement, these groups can often be left worse off than before. Government support needs to be carried out in a way that encourages maximum deployment, while also enforcing regulations that protect the rights of rural communities.

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21

Pavani, Claudio Damasceno. "Potencial biotecnológico do metagenoma de rúmen bovino da raça nelore (Bos tauros indicus), visando à desconstrução da biomassa vegetal /." Jaboticabal, 2017. http://hdl.handle.net/11449/151118.

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Orientador: Jackson Antonio Marcondes Souza
Banca: Manoel Victor Franco Lemos
Banca: Maria de lourdes Teixeira de Moraes Polizeli
Banca: María Eugenia Guazzaroni
Banca: Alessandro de Mello Varani
Resumo: A comunidade mundial busca pela obtenção de biocombustível celulósico, embora ainda seja um grande desafio a desconstrução do arranjo lignocelulósico para obtenção de açúcares livres de forma eficiente e economicamente viável. A fim de superar tais desafios, avanços conquistados pela metagenômica ressaltam sua aplicação como alternativa para compreender e desvendar o grande potencial metabólico presente nos ambientes, buscando encontrar em tais ambientes novas enzimas que atuem de forma eficiente na desconstrução do material lignocelulósico. Neste trabalho utilizou-se, a abordagem metagenômica para caracterização de genes com potencial para degradar biomassa vegetal e também para avaliação da diversidade taxonômica do ambiente ruminal bovino (Cow_1), bem como comparar os dados coletados com outros metagenomas disponíveis. Amostras de conteúdo ruminal de três bovinos machos da raça Nelore foram coletadas para a obtenção da amostra de DNA metagenômico, que posteriormente foi sequenciada pelo sequenciador HiScan SQ (Illumina). Foram obtidas aproximadamente 63 milhões de sequências (Cow _1), 2 x 100 pb. Dentre os 26 filos encontrados o filo Bacteroidetes foi o mais abundante, seguido de Firmicutes e Proteobacteria. Para a anotação gênica foi utilizado os bancos de dados Pfam, GO, KEGG e CAZy. Foram associadas ORFs relacionadas a 86 famílias de Glycoside Hydrolases (GHs), 52 famílias de Carbohydrate-Binding Modules (CBMs), 4 famílias de Auxiliary Activities (AAs), 16 famílias de C... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The world community search to obtain cellulosic biofuel; however the deconstruction of the lignocellulosic arrangement to obtain free sugars in an efficient and economically viable way is still a great challenge. Advances achieved through the metagenomic emphasize its application as an alternative to unfold the great metabolic potential present in the environments in order to overcome such challenges. Thus, a metagenomic approach was used to characterize genes with potential to degrade plant biomass and to evaluate the taxonomic diversity of the Nelore bovine ruminal environment. Samples were collected from three bovine males to obtain the DNA sample, which were sequentially sequenced by the HiScan SQ (Illumina) sequencer. About 63 million sequences, 2 x 100 bp, were obtained. Among the 26 phyla found, Bacteroidetes was the most abundant, followed by Firmicutes and Proteobacteria. For gene annotation was used the Pfam, GO, KEGG and CAZy databases. A total of 86 families of Glycoside Hydrolases (GHs), 52 families of Carbohydrate Binding Modules (CBMs), 4 families of Auxiliary Activities (AAs), 16 Esterase Carbohydrate (CEs), 55 GlycosylTransferases (GTs) Polysaccharide Lyases (PLs), 1 S-homology homology (SLH) domain and 1 family of cohesin and dockerine was associated. these genes are related to the formation of the enzymatic complex for deconstruction of plant biomass (cellulosome). The cow_1 metagenome presented a greater number of genes related to deconstruction of plant b... (Complete abstract click electronic access below)
Doutor

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Ferreira, Adriana Scheffer Quintela. "Estudo de indices de proximidade ao limite de estabilidade de tensão e aplicação na seleção de contingencias." [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/260125.

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Orientador: Carlos Alberto de Castro Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
Made available in DSpace on 2018-08-02T10:31:52Z (GMT). No. of bitstreams: 1 Ferreira_AdrianaSchefferQuintela_M.pdf: 36386637 bytes, checksum: 5b79e904173826d897c65c9512aaf197 (MD5) Previous issue date: 2002
Mestrado

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Bayerová, Zuzana. "Surovinová a energetická závislost čínské a indické ekonomiky." Master's thesis, Vysoká škola ekonomická v Praze, 2010. http://www.nusl.cz/ntk/nusl-71820.

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The aim of the diploma thesis is to analyze People's Republic of China and India from the point of view of their mineral and energy dependence, where mineral means the necessity to import raw materials for the industry, while energy corresponds to imports of energy resources, namely coal, oil and natural gas. The secondary aim is so called 3C-Analysis (Comparison, Competition, Cooperation), which compares these two economies and evaluates their mutual relationships. The thesis is divided into three main parts - China, India, 3C-Analysis. The subchapters focuse on partial analysis, which are the definition of strategic minerals based on the key industrial branches, the determination of causes of mineral resources dependence and problems outcoming from current structure of energy imports, as well as the analysis and evaluation of the steps leading to the dependence elimination. The text also contains information about the situation in industrial and energy sector of both countries and basic data of raw materials production, reserves, consumption and imports.

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Saussay, Aurélien. "Three essays on energy prices and the energy transition." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEH156.

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Cette thèse tire parti de la remarquable volatilité des prix de l'énergie, tant temporelle que géographique, au cours des deux dernières décennies pour identifier les impacts de l'augmentation du prix des énergies fossiles sur les agents économiques. L'une des principales sources de cette volatilité, la révolution des gaz de schistes aux Etats-Unis, est tout d’abord examinée, avant d'analyser deux sujets de politiques économiques en lien avec la mise en place de la taxation du carbone : le risque de relocalisation de l'investissement industriel résultant d'une dégradation de la compétitivité, et les impacts redistributifs de l'augmentation des prix de l'essence pour les ménages.Le premier chapitre réalise une analyse statistique détaillée d'une base de données originale de 40 000 puits de gaz de schistes américains afin de calibrer un modèle technico-économique de la profitabilité de l'extraction du gaz de schistes, et conclut que la révolution des gaz de schistes n'est pas reproductible en Europe continentale. Le second chapitre combine une base de données de 70 000 transactions de fusions et acquisitions industrielles recouvrant 41 pays sur une période de 20 ans avec un indice des prix de l'énergie industriels, pour identifier l'impact des prix relatifs de l'énergie sur la localisation de l'investissement industriel. Les résultats impliquent que les firmes tendent à entreprendre plus d'investissements transfrontaliers lorsque les prix domestiques de l'énergie augmentent relativement aux prix étrangers, ce qui confirme l’hypothèse de Pollution Haven. Des simulations contrefactuelles démontrent toutefois que la magnitude de cet effet reste limitée. Le troisième chapitre introduit un modèle dynamique simple de la consommation d'essence des ménages, appliquant le cadre des habitudes rationnelles à la représentation de la dimension intertemporelle de la demande d'essence. Ce modèle est ensuite estimé sur un micropanel de ménages issu du PSID entre 1999 et 2015, en combinaison avec des prix localisés de l'essence. Ces estimations démontrent que la consommation d'essence des ménages est sujette à la formation d'habitude et aux anticipations, et résultent en une élasticité de long terme de -0,88. Des micro-simulations complémentaires suggèrent également l'existence d'interactions entre l'hétérogénéité des comportements dynamiques et la régressivité de l'augmentation du prix de l'essence.Les résultats de cette thèse renforcent la nécessité des politiques économiques compensatoires visant à améliorer l'acceptabilité de la taxation du carbone par les agents économiques, et fournit des outils qui peuvent contribuer à leur conception et leur calibration
This thesis takes advantage of the remarkable volatility of energy prices across both time and space over the past two decades to identify the impacts of increased fossil fuel energy prices on economic agents. It first examines one of the main sources of this renewed energy price volatility, the U.S. shale gas revolution, before turning to the analysis of two policy issues related to the implementation of carbon pricing: the risk of industrial investment relocation as a consequence of degraded competitiveness, and the distributional impacts of increased gasoline prices for households. The first chapter performs a detailed statistical analysis of an original dataset of 40,000 U.S. shale gas wells to calibrate a techno-economic model of shale gas extraction profitability, and finds that the shale gas revolution is not transferrable to continental Europe. The second chapter combines a database of 70,000 industrial M&A transactions covering 20 years and 41 countries with a sectoral industrial energy price index to identify the impact of relative energy prices on industrial investment location. Findings imply that firms tend to engage in more cross-border investments when their domestic energy prices increase in relative terms against foreign prices, which broadly supports the pollution haven hypothesis. Counterfactual policy simulations show that this effect is limited though. The third chapter develops a simple dynamic model of household gasoline consumption, using the rational habits framework to capture the intertemporal dimension of gasoline demand. This model is then estimated on PSID household-level data between 1999 and 2015 using localized gasoline prices. Estimation results show that households exhibit habits formation and forward-looking behavior in their gasoline consumption, and find a -0.88 long term price elasticity. Micro-simulations also find suggestive evidence of interactions between dynamic heterogeneity and the regressivity of gasoline price increases. The findings of this thesis strengthen the case for compensatory policies aimed at improving carbon pricing acceptance by economic agents, and provide tools that can contribute to their design and calibration

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Walker, Robin J. "Awakening tiger India's quest for expanded influence in the world." Thesis, Monterey, Calif. : Naval Postgraduate School, 2008. http://bosun.nps.edu/uhtbin/hyperion-image.exe/08Mar%5FWalker%5FRobin.pdf.

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Анотація:

Thesis (M.A. in Security Studies (South Asia))--Naval Postgraduate School, March 2008.
Thesis Advisor(s): Knopf, Jeffrey W. ; Lavoy, Peter R. "March 2008." Description based on title screen as viewed on May 16, 2008. Includes bibliographical references (p. 91-103). Also available in print.

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Pareja, Fernández Pablo Andrés. "Desarrollo de Indices de Desempeño del Consumo Energético y de Agua Sanitaria en Edificios de Oficinas de Santiago." Tesis, Universidad de Chile, 2007. http://repositorio.uchile.cl/handle/2250/104768.

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El presente informe analiza globalmente el estado actual de los edificios de oficina de Santiago para aportar en materia de eficiencia energética en el desarrollo de futuras políticas públicas, plantear soluciones a los problemas que afectan a este tipo de construcciones y ser una pauta para su diseño. Para efectos de este trabajo se eligió una zona térmica y un tipo de edificios en particular; sin embargo, se desarrolló una metodología que puede ser usada en otros tipos de edificios o de otras zonas geográficas del país. En una primera parte del informe se repasan los distintos tipos de energías existentes y sus diferencias, se definen las condiciones de confort dentro de una oficina, cómo se abordan éstas en los distintos aspectos y cuáles son las variables que la definen. Luego, mediante indicadores se estudian los consumos energéticos y de agua potable en una muestra de edificios de oficina. Después se analiza la distribución de los consumos y se examina la incidencia de los gastos de estos suministros en los costos totales de la oficina. Por último se calculan las emisiones de CO2 emitidas al medio ambiente por el funcionamiento de éstas. Los principales índices son los siguientes: —Consumo anual de electricidad: 95,4 kWh/m2 —Consumo anual de gas natural: 34,6 kWh/m2 —Consumo anual de agua potable: 1,43 m3 /m2 Finalmente se concluye que las emisiones de CO2 son más de 50 kg/m2 de oficina y que estas emisiones ocurren tanto dentro de la oficina como en los centros de conversión de energía. Además los costos anuales en energía y agua potable son del orden de 10150 $/m2, lo que corresponde al 9% aproximado del arriendo de las oficinas.

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Arias, Cazco Diego Anibal. "Indice de detección de problemas de estabilidad de tensión en base a WAMS." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/111991.

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Magíster en Ciencias de la Ingeniería, Mención Eléctrica
En la actualidad los sistemas eléctricos de potencia a menudo operan bajo condiciones de estrés, para satisfacer una demanda que es cada vez mayor, con una expansión de la red de transmisión relativamente limitada. Esto genera la necesidad de utilizar nuevos recursos de equipos, metodologías de análisis y herramientas computacionales para hacer frente a esta situación. En particular, la estabilidad de tensión ocupa un lugar preponderante dentro de los nuevos fenómenos que ponen en riesgo la seguridad del sistema, por ello reviste gran importancia el uso de indicadores que alerten de manera temprana sobre la posible ocurrencia de fenómenos que pudieran derivar en un colapso de tensión en la red. En este campo uno de los avances más promisorios es el uso de mediciones sincronizadas entregadas por los llamados Sistemas de Medición de Área Amplia (Wide Area Measurement Systems, WAMS en inglés), quienes obtienen la información de entrada para los indicadores de estabilidad de tensión en base a PMU (Phasor Measurement Unit). Al revisar el estado del arte en relación a estos índices de detección de estabilidad de tensión en tiempo real, se constata que la mayoría de los estudios e investigaciones evalúan los márgenes de estabilidad de tensión en el punto crítico (punta de la curva nariz), es decir, detectando la distancia al punto teórico de máxima transferencia de potencia del sistema. Este tipo de métodos, pueden llevar a análisis imprecisos ya que en el punto de máxima transferencia los niveles de tensión llegan a valores muy inferiores a los límites operacionales reales por lo que en la práctica se podría llegar a una situación de colapso de tensión sin ser detectado por esos indicadores. Por otra parte, para tener un análisis completo no basta con determinar la máxima trasferencia de potencia por el sistema de transmisión, sino que se debe verificar que el sistema tenga además los medios para proveer la cantidad de reactivos que dicha transferencia y carga requieren. Considerando que la estimación de estado en base a mediciones sincronizadas está disponible, este trabajo de investigación se dirige hacia el desarrollo de una mejora en la línea de índices de estabilidad de tensión usando dichas mediciones. Se propone un indicador llamado VSI-OC (Voltage Stability Index under Operational Conditions), el cual considera límites reales de operación y una evaluación de las reservas de reactivos del sistema. El indicador se obtiene de un problema de optimización propuesto, en el cual, se define el máximo incremento de carga en la barra como función objetivo, tomando como restricciones de igualdad las ecuaciones de flujo de potencia, y como restricciones de desigualdad los límites de reactivos de generación. Especialmente, el indicador considera límites de tensión de acuerdo a exigencias operativas, es decir, los estipulados en las respectivas normas técnicas. Para validar el método propuesto, se aplica a una simulación en un modelo del SIC de 114 barras, en el cual, se prueba el desempeño del índice propuesto bajo diferentes escenarios con el objeto de abordar un amplio espectro de estados de operación. Los índices cuantifican la seguridad del sistema en una escala de 0 a 1 , en donde, un valor cercano a 1 indica que la barra de carga dispone de un buen margen de estabilidad y un valor cercano a 0 indica que la barra esta cerca a violar los límites operacionales del sistema. Los resultados indican que el método cumple con el objetivo propuesto, permitiendo monitorear adecuadamente la proximidad de eventos que pueden derivar en un colapso de tensión. El índice VSI-OC da señales de alerta con mayor anticipación que los índices convencionales. De esta manera, el operador puede realizar una asignación de recursos de potencia reactiva en forma óptima y tomar las acciones de control necesarias para mantener el sistema en condiciones de operación normal, permitiendo una operación segura. Como trabajo futuro se propone extender la investigación a aplicaciones en tiempo real en base a WAMS, y enfrentar los mayores retos en el desarrollo de estas tecnologías, tales como manejo de congestiones en la red, control de flujos en tiempo real, control y protección en sistemas de área amplia (WAMPAC en inglés).

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Amazirh, Abdelhakim. "Monitoring crops water needs at high spatio-temporal resolution by synergy of optical/thermal and radar observations." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30101.

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L'optimisation de la gestion de l'eau en agriculture est essentielle dans les zones semi-arides afin de préserver les ressources en eau qui sont déjà faibles et erratiques dues à des actions humaines et au changement climatique. Cette thèse vise à utiliser la synergie des observations de télédétection multispectrales (données radar, optiques et thermiques) pour un suivi à haute résolution spatio-temporelle des besoins en eau des cultures. Dans ce contexte, différentes approches utilisant divers capteurs (Landsat-7/8, Sentinel-1 et MODIS) ont été developpées pour apporter une information sur l'humidité du sol (SM) et le stress hydrique des cultures à une échelle spatio-temporelle pertinente pour la gestion de l'irrigation. Ce travail va parfaitement dans le sens des objectifs du projet REC "Root zone soil moisture Estimates at the daily and agricultural parcel scales for Crop irrigation management and water use impact: a multi-sensor remote sensing approach" (http://rec.isardsat.com/) qui visent à estimer l'humidité du sol dans la zone racinaire (RZSM) afin d'optimiser la gestion de l'eau d'irrigation. Des approches innovantes et prometteuses sont mises en place pour estimer l'évapotranspiration (ET), RZSM, la température de surface du sol (LST) et le stress hydrique de la végétation à travers des indices de SM dérivés des observations multispectrales à haute résolution spatio-temporelle. Les méthodologies proposées reposent sur des méthodes basées sur l'imagerie, la modélisation du transfert radiatif et la modélisation du bilan hydrique et d'énergie et sont appliquées dans une région à climat semi-aride (centre du Maroc). Dans le cadre de ma thèse, trois axes ont été explorés. Dans le premier axe, un indice de RZSM dérivé de LST-Landsat est utilisé pour estimer l'ET sur des parcelles de blé et des sols nus. L'estimation par modélisation de ET a été explorée en utilisant l'équation de Penman-monteith modifiée obtenue en introduisant une relation empirique simple entre la résistance de surface (rc) et l'indice de RZSM. Ce dernier est estimé à partir de la température de surface (LST) dérivée de Landsat, combinée avec les températures extrêmes (en conditions humides et sèches) simulée par un modèle de bilan d'énergie de surface piloté par le forçage météorologique et la fraction de couverture végétale dérivée de Landsat. La méthode utilisée est calibrée et validée sur deux parcelles de blé situées dans la même zone près de Marrakech au Maroc. Dans l'axe suivant, une méthode permettant de récupérer la SM de la surface (0-5 cm) à une résolution spatiale et temporelle élevée est développée à partir d'une synergie entre données radar (Sentinel-1) et thermique (Landsat) et en utilisant un modèle de bilan d'énergie du sol. L'approche développée a été validée sur des parcelles agricoles en sol nu et elle donne une estimation précise de la SM avec une différence quadratique moyenne en comparant à la SM in situ, égale à 0,03 m3 m-3. Dans le dernier axe, une nouvelle méthode est développée pour désagréger la MODIS LST de 1 km à 100 m de résolution en intégrant le SM proche de la surface dérivée des données radar Sentinel-1 et l'indice de végétation optique dérivé des observations Landsat. Le nouvel algorithme, qui inclut la rétrodiffusion S-1 en tant qu'entrée dans la désagrégation, produit des résultats plus stables et robustes au cours de l'année sélectionnée. Dont, 3,35 °C était le RMSE le plus bas et 0,75 le coefficient de corrélation le plus élevé évalués en utilisant le nouvel algorithme
Optimizing water management in agriculture is essential over semi-arid areas in order to preserve water resources which are already low and erratic due to human actions and climate change. This thesis aims to use the synergy of multispectral remote sensing observations (radar, optical and thermal data) for high spatio-temporal resolution monitoring of crops water needs. In this context, different approaches using various sensors (Landsat-7/8, Sentinel-1 and MODIS) have been developed to provide information on the crop Soil Moisture (SM) and water stress at a spatio-temporal scale relevant to irrigation management. This work fits well the REC "Root zone soil moisture Estimates at the daily and agricultural parcel scales for Crop irrigation management and water use impact: a multi-sensor remote sensing approach" (http://rec.isardsat.com/) project objectives, which aim to estimate the Root Zone Soil Moisture (RZSM) for optimizing the management of irrigation water. Innovative and promising approaches are set up to estimate evapotranspiration (ET), RZSM, land surface temperature (LST) and vegetation water stress through SM indices derived from multispectral observations with high spatio-temporal resolution. The proposed methodologies rely on image-based methods, radiative transfer modelling and water and energy balance modelling and are applied in a semi-arid climate region (central Morocco). In the frame of my PhD thesis, three axes have been investigated. In the first axis, a Landsat LST-derived RZSM index is used to estimate the ET over wheat parcels and bare soil. The ET modelling estimation is explored using a modified Penman-Monteith equation obtained by introducing a simple empirical relationship between surface resistance (rc) and a RZSM index. The later is estimated from Landsat-derived land surface temperature (LST) combined with the LST endmembers (in wet and dry conditions) simulated by a surface energy balance model driven by meteorological forcing and Landsat-derived fractional vegetation cover. The investigated method is calibrated and validated over two wheat parcels located in the same area near Marrakech City in Morocco. In the next axis, a method to retrieve near surface (0-5 cm) SM at high spatial and temporal resolution is developed from a synergy between radar (Sentinel-1) and thermal (Landsat) data and by using a soil energy balance model. The developed approach is validated over bare soil agricultural fields and gives an accurate estimates of near surface SM with a root mean square difference compared to in situ SM equal to 0.03 m3 m-3. In the final axis a new method is developed to disaggregate the 1 km resolution MODIS LST at 100 m resolution by integrating the near surface SM derived from Sentinel-1 radar data and the optical-vegetation index derived from Landsat observations. The new algorithm including the S-1 backscatter as input to the disaggregation, produces more stable and robust results during the selected year. Where, 3.35 °C and 0.75 were the lowest RMSE and the highest correlation coefficient assessed using the new algorithm

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Ягуп, Катерина Валеріївна. "Покращання енергетичних показників електротехнічних систем із застосуванням пошукової оптимізації на комп'ютерних моделях". Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/35541.

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Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.09.03 – електротехнічні комплекси та системи. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. Розглядаються методи оптимізації режимів систем електропостачання з несиметричними і нелінійними навантаженнями з метою підвищення енергетичних показників і розрахунку симетро-компенсуючих пристроїв. Обґрунтовано необхідність і можливість застосування комп'ютерних засобів, розроблено узагальнені алгоритми реалізації пошукової оптимізації. Розроблені методи успішно застосовані для оптимізації режимів в трипровідних і чотирипровідних системах, в тому числі в системах з взаємно-зв'язаними індуктивностями, в системах залізничного електропостачання, в системі з нейтралером, в системах живлення асинхронних двигунів, освітлювальних приладів високого тиску, в системах з силовими активними фільтрами, а також для випадків кількох навантажень з урахуванням вкладу кожного з них в зниження енергетичних показників системи.
Thesis for a Doctor’s degree in Engineering Science by specialty 05.09.03 – Electrical Engineering Complexes and Systems. – National Technical University "Kharkov Polytechnic Institute", Kharkiv, 2018. The dissertation is devoted to the development and research of optimization methods of power supply systems modes in electrotechnical systems with asymmetric and nonlinear loads in order to increase the energy indices and calculate the parameters of symmetry-compensating devices using mathematical and computer models, and using search engine optimization implemented with the use of modern software of computer mathematics. The necessity and the possibility of using computer tools for solving set tasks are substantiated. The generalized algorithms for implementing search engine optimization using modern software packages are developed. The possibilities of applying different optimization criteria for solving the problems of increasing the energy indices of power supply systems with asymmetric and nonlinear loads are shown. The properties of the search engine optimization system have been found to extrude the inappropriate element of the synthesized device, as well as the possibility of releasing the optimization variables by increasing their amount, which allows us to get ahead of a faster locating of the local minimum and then recalculate the parameters corresponding to the global minimum are shown. The developed method of search optimization using the models of power supply systems has been successfully applied for optimization of regimes and synthesis of symmetry-compensating devices in three-phase three-wire and four-wire systems of power supply. The possibilities of using the optimization tools for Mathcad and Matlab software packages are considered, in particular, using zero-order methods that do not require the calculation of derivatives, such as the deformed polyhedron method and the conjugate gradient method. The algorithm of load equivalence is proposed, with the help of which the symmetrical and asymmetric parts of the load are allocated. After this, the parameters of the balancing device are determined with sufficient accuracy by means of the Steinmetz and Kennely formulas. The method of currents direct symmetric component rotation with the preservation of symmetry and the mode of full reactive power compensation is proposed. For four-wire systems, the use of a generalized reactive element in a symmetry-compensating device is proposed, which accelerates the process of achieving the optimal solution. The method of determining the optimal mode based on the decomposition of the power supply system, which improves the convergence of the solution processes, is developed. Systems of power supply containing inductively coupled elements are considered. The calculation of the symmetry-compensating device of the traction system of the alternating current railway power supply is considered. A four-wire system with a neutralizer was studied, with the help of search engine optimization the parameters of the symmetry-compensating device were determined which allows to balance and counterbalance such a system. The possibilities of optimization of the regime in the power system of asynchronous motors, including the asymmetry of the supply network, are shown. Compensation of reactive power allows here to reduce the consumed currents and increase the efficiency of the system. To find the optimal modes of systems with an arc discharge, visual models have been developed that are adapted for use with the SimPowerSystem library elements. With the help of these models, the possibilities of increasing the power indices of arc discharge power supply systems, including high-pressure lighting devices, are investigated. It was shown that the optimization of the power factor alone, calculated with the help of the pro-posed methods, leads to decrease in the current consumed by the fundamental harmonic, which substantially reduces the losses in the transmission lines. For a thyristor compensator with single-stage switching, the advantage of symmetric control is proven, which greatly improves the spectrum of harmonics of supply currents. The use of the search optimization method to increase the power factor is shown without the use of traditional rather complicated control systems by power active filters. Comparison signals are used as control signals, synchronized with the phase voltages of the supply system. The amplitudes of these signals are accepted as optimization variables, and the optimization criterion is determined by the balance of active power in the system, which is characterized by the stabilization of the periodic voltage on the storage capacitor of the power active filter. The problems of synthesis of symmetric-compensating devices for several asymmet-rical loads in parallel and cascade connection are considered. The task is to determine the parameters of the symmetric-compensating devices for each of the loads separately, and the contribution to the creation of asymmetry and the generation of reactive power of each connected load must be taken into account. This problem is solved by the method of search optimization, and it is shown that, in forming the objective function, currents in the feeders, supplying energy from the point of connection of the load to the network to the common point of connection of the load and the symmetric-compensating device. It is effective to use the developed decomposition method, which makes it possible to simplify and accelerate the determination of the optimal regime of the system under study, taking into account the contribution of each load to the reduction of the energy parameters of the system as a whole. The case is also analyzed when two loads consisting of both unbalanced linear and nonlinear loads are simultaneously connected to the network. Optimization of the regime with increasing power factor is achieved by using a parallel power active filter with control over the proposed optimization algorithm. Methods and algorithms of search optimization developed for the purposes of increasing the energy indicators of power supply systems with asymmetric and nonlinear consumers developed and presented in the thesis work are characterized by high accuracy, the maximum possible use of computer technology, low computer time and the possibility of complete automation of design and research procedures in solving theoretical and practical tasks related to increasing energy performance and quality of electrical energy in power supply systems.

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Ягуп, Катерина Валеріївна. "Покращання енергетичних показників електротехнічних систем із застосуванням пошукової оптимізації на комп'ютерних моделях". Thesis, Харківський національний університет міського господарства ім. О. М. Бекетова, 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/35543.

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Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.09.03 – електротехнічні комплекси та системи. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. Розглядаються методи оптимізації режимів систем електропостачання з несиметричними і нелінійними навантаженнями з метою підвищення енергетичних показників і розрахунку симетро-компенсуючих пристроїв. Обґрунтовано необхідність і можливість застосування комп'ютерних засобів, розроблено узагальнені алгоритми реалізації пошукової оптимізації. Розроблені методи успішно застосовані для оптимізації режимів в трипровідних і чотирипровідних системах, в тому числі в системах з взаємно-зв'язаними індуктивностями, в системах залізничного електропостачання, в системі з нейтралером, в системах живлення асинхронних двигунів, освітлювальних приладів високого тиску, в системах з силовими активними фільтрами, а також для випадків кількох навантажень з урахуванням вкладу кожного з них в зниження енергетичних показників системи.
Thesis for a Doctor’s degree in Engineering Science by specialty 05.09.03 – Electrical Engineering Complexes and Systems. – National Technical University "Kharkov Polytechnic Institute", Kharkiv, 2018. The dissertation is devoted to the development and research of optimization methods of power supply systems modes in electrotechnical systems with asymmetric and nonlinear loads in order to increase the energy indices and calculate the parameters of symmetry-compensating devices using mathematical and computer models, and using search engine optimization implemented with the use of modern software of computer mathematics. The necessity and the possibility of using computer tools for solving set tasks are substantiated. The generalized algorithms for implementing search engine optimization using modern software packages are developed. The possibilities of applying different optimization criteria for solving the problems of increasing the energy indices of power supply systems with asymmetric and nonlinear loads are shown. The properties of the search engine optimization system have been found to extrude the inappropriate element of the synthesized device, as well as the possibility of releasing the optimization variables by increasing their amount, which allows us to get ahead of a faster locating of the local minimum and then recalculate the parameters corresponding to the global minimum are shown. The developed method of search optimization using the models of power supply systems has been successfully applied for optimization of regimes and synthesis of symmetry-compensating devices in three-phase three-wire and four-wire systems of power supply. The possibilities of using the optimization tools for Mathcad and Matlab software packages are considered, in particular, using zero-order methods that do not require the calculation of derivatives, such as the deformed polyhedron method and the conjugate gradient method. The algorithm of load equivalence is proposed, with the help of which the symmetrical and asymmetric parts of the load are allocated. After this, the parameters of the balancing device are determined with sufficient accuracy by means of the Steinmetz and Kennely formulas. The method of currents direct symmetric component rotation with the preservation of symmetry and the mode of full reactive power compensation is proposed. For four-wire systems, the use of a generalized reactive element in a symmetry-compensating device is proposed, which accelerates the process of achieving the optimal solution. The method of determining the optimal mode based on the decomposition of the power supply system, which improves the convergence of the solution processes, is developed. Systems of power supply containing inductively coupled elements are considered. The calculation of the symmetry-compensating device of the traction system of the alternating current railway power supply is considered. A four-wire system with a neutralizer was studied, with the help of search engine optimization the parameters of the symmetry-compensating device were determined which allows to balance and counterbalance such a system. The possibilities of optimization of the regime in the power system of asynchronous motors, including the asymmetry of the supply network, are shown. Compensation of reactive power allows here to reduce the consumed currents and increase the efficiency of the system. To find the optimal modes of systems with an arc discharge, visual models have been developed that are adapted for use with the SimPowerSystem library elements. With the help of these models, the possibilities of increasing the power indices of arc discharge power supply systems, including high-pressure lighting devices, are investigated. It was shown that the optimization of the power factor alone, calculated with the help of the pro-posed methods, leads to decrease in the current consumed by the fundamental harmonic, which substantially reduces the losses in the transmission lines. For a thyristor compensator with single-stage switching, the advantage of symmetric control is proven, which greatly improves the spectrum of harmonics of supply currents. The use of the search optimization method to increase the power factor is shown without the use of traditional rather complicated control systems by power active filters. Comparison signals are used as control signals, synchronized with the phase voltages of the supply system. The amplitudes of these signals are accepted as optimization variables, and the optimization criterion is determined by the balance of active power in the system, which is characterized by the stabilization of the periodic voltage on the storage capacitor of the power active filter. The problems of synthesis of symmetric-compensating devices for several asymmet-rical loads in parallel and cascade connection are considered. The task is to determine the parameters of the symmetric-compensating devices for each of the loads separately, and the contribution to the creation of asymmetry and the generation of reactive power of each connected load must be taken into account. This problem is solved by the method of search optimization, and it is shown that, in forming the objective function, currents in the feeders, supplying energy from the point of connection of the load to the network to the common point of connection of the load and the symmetric-compensating device. It is effective to use the developed decomposition method, which makes it possible to simplify and accelerate the determination of the optimal regime of the system under study, taking into account the contribution of each load to the reduction of the energy parameters of the system as a whole. The case is also analyzed when two loads consisting of both unbalanced linear and nonlinear loads are simultaneously connected to the network. Optimization of the regime with increasing power factor is achieved by using a parallel power active filter with control over the proposed optimization algorithm. Methods and algorithms of search optimization developed for the purposes of increasing the energy indicators of power supply systems with asymmetric and nonlinear consumers developed and presented in the thesis work are characterized by high accuracy, the maximum possible use of computer technology, low computer time and the possibility of complete automation of design and research procedures in solving theoretical and practical tasks related to increasing energy performance and quality of electrical energy in power supply systems.

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Aranha, Neto Edison Antonio Cardoso. "Alocação de chaves automatizadas em redes de distribuição utilizando múltiplos critérios." Florianópolis, SC, 2006. http://repositorio.ufsc.br/xmlui/handle/123456789/89441.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Elétrica.
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O presente trabalho tem como objetivo o desenvolvimento de uma metodologia para a alocação de chaves automatizadas em redes de distribuição, utilizando ferramentas de otimização multicritério para atender a diferentes políticas de desempenho. Devido à complexidade do problema, a metodologia foi divida em três partes, denominadas de módulos. O primeiro módulo a ser executado é o Modulo de Reconfiguração, cuja função principal é estabelecer os pontos candidatos à alocação de uma chave automatizada. A seguir, o Módulo de Confiabilidade calcula para estes pontos o impacto nos índices de confiabilidade causados pela alocação de uma chave. O terceiro e último módulo, o Módulo Multicritério, é responsável pelo cálculo da ordem de mérito (hierarquização) das posições candidatas a receberem uma chave, de acordo com as preferências do decisor. A metodologia para alocação de chaves automatizadas foi aplicada em um sistema teste composto por três alimentadores obtidos na literatura internacional e em um sistema composto por dois alimentadores baseados em dados de consumidores e cargas reais e também nas configurações e registros de falhas, manobras e manutenção de uma concessionária brasileira. Os resultados obtidos demonstram a viabilidade da metodologia desenvolvida e mostram os ganhos introduzidos ao sistema com a alocação de chaves automatizadas.

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Кольсун, В. А. "Способи поліпшення енергетичних показників систем живлення енергоємних установок з регульованим електроприводом". Дисертація, Видавництво НГУ, 2010. http://ir.nmu.org.ua/handle/123456789/120.

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Анотація:

Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.09.03 – Електротехнічні комплекси та системи. – Національний гірничий університет, Дніпропетровськ, 2010.
Диссертация на соискание ученой степени кандидата технических наук по специальности 05.09.03 – Электротехнические комплексы и системы. – Национальный горный университет, Днепропетровск, 2010
The thesis for a candidate’s degree by specialty 05.09.03 – Electrotechnical complexes and systems. – National Mining University, Dnipropetrovsk, 2010
Дисертація присвячена поліпшенню показників якості електроенергії в системах живлення енергоємних установок з регульованим електроприводом. В роботі розроблені теоретичні основи аналізу, розрахунку та прогнозування показників енергоспоживання в умовах нестабільності навантажень та створення на цій основі високоефективних систем живлення енергоємних установок з регульованим електроприводом. Отримані залежності зміни енергетичних показників з урахуванням характеру навантаження установок. На основі критичного аналізу відомих методів розрахунку і оцінки режимів взаємовпливу та складності їх практичного використання в системах живлення енергоємних установок з перетворювальними пристроями, обґрунтовано новий підхід математичного моделювання вказаних режимів і створено уніфікований алгоритм автоматизованих багатоваріантних розрахунків. Алгоритм передбачає визначення гармонік струму і напруги в загальній мережі живлення групи приймачів з регульованим електроприводом, а також провалу фазної (лінійної) напруги для всіх варіантів комутації. Проведені експериментальні дослідження та здійснена практична реалізація систем і пристроїв розрахунку енергетики розглянутих систем живлення
Диссертационная работа посвящена улучшению энергетических показателей в системах питания энергоемких установок с регулируемым электроприводом за счет активного контроля и влияния на их формирование с использованием компенсационных свойств непосредственно преобразователей. В работе разработаны теоретические основы анализа, расчета и прогнозирования показателей энергопотребления в условиях нестабильности нагрузок и создания высокоэффективных систем питания энергоемкими установками и комплексами с регулируемым электроприводом. Получены зависимости изменения энергетических показателей с учетом характера нагрузок установок (основное внимание уделено таким установкам, как турбомеханизмы – на примерах турбокомпрессоров, и механизмам циклического действия – на примерах прокатного стана, главного электропривода блюминга). В работе предложены энергетические модели, показывающие энергетическую связь между объектами электропотребления и объектами электроснабжения в системах питания энергоемкими установками с регулируемым электроприводом, которые адекватно отображают формирование энергобаланса в сложных системах в направлении «нагрузка-преобразователь-сеть». Анализ, расчеты и прогнозирование показателей энергоэффективности осуществляются структурно-аналитическим моделированием, включающее использование энергетических моделей и элементов дискретного гармонического синтеза. Повышение энергетической эффективности систем питания энергоемких установок с регулируемым электроприводом осуществляется комплексным подходом с приоритетом компенсации неактивных составляющих на технологических уровнях с использованием компенсирующих способностей непосредственно преобразовательными устройствами в цепях питания и управления, а компенсацию остаточного уровня внешними компенсаторами. Проведены исследования неустановившихся режимов преобразователей регулируемых электроприводов энергоемких установок. Показано, что определение энергетических характеристик установок с преобразовательными установками и нестабильными нагрузками связано со специфическими условиями формирования составляющих мощности и гармоник тока на интервалах изменений нагрузки. Доказано, что указанные составляющие мощности пропорционально зависят от скорости изменения нагрузки (тока) и угла управления. На основании критического анализа известных методов расчета и оценки режимов взаимовлияния и электромагнитной совместимости и сложности их практического использования в системах питания с преобразовательными установками, обосновано новый подход математического моделирования указанных режимов, основанный на решении дифференциальных уравнений за специальной схемой вычисления производных и созданный унифицированный алгоритм автоматизированных многовариантных расчетов. Алгоритм вычисляет гармоники тока и напряжения в общей сети питания группы приемников с преобразовательными устройствами, а также провала фазного (линейного) напряжения для всех вариантов коммутации (учитывая также совпадение коммутаций N-го количества преобразователей). Проведены экспериментальные исследования и выполнена практическая реализация систем и устройств расчета энергетики рассмотренных систем
The thesis is devoted to improving power indices in power-consuming industries by means of model problem solution and power processes calculation of different electric drive systems. Theoretical fundamentals of power indices analysis, calculation and prediction under instability conditions are developed. High-performance group electrical drive systems are founded by means these fundamentals. Main power dependences were taken into account plants loading. New mathematical modeling approaches are grounded on the base of known calculation methods analysis and estimation of inter-influence conditions and electromagnetic compatibility and differential equations calculation by mean special elaborated method of solving derivative. It is developed the uniform algorithm of automatic poly-variant solving. The algorithm makes provision for determining current and voltage harmonics of net which supply converters group. Phase and linear voltage drops for different events may be calculated by mean the algorithm. Experimental researches are lead. Practical achievement of this systems and registration devices of such systems are made

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Haouas, Nabiha. "Wind energy analysis and change point analysis." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22554.

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L’énergie éolienne, l’une des énergies renouvelables les plus compétitives, est considérée comme une solution qui remédie aux inconvénients de l’énergie fossile. Pour une meilleure gestion et exploitation de cette énergie, des prévisions de sa production s’avèrent nécessaires. Les méthodes de prévisions utilisées dans la littérature permettent uniquement une prévision de la moyenne annuelle de cette production. Certains travaux récents proposent l’utilisation du Théorème Central Limite (TCL), sous des hypothèses non classiques, pour l’estimation de la production annuelle moyenne de l’énergie éolienne ainsi que sa variance pour une seule turbine. Nous proposons dans cette thèse une extension de ces travaux à un parc éolien par relaxation de l’hypothèse de stationnarité la vitesse du vent et la production d’énergie, en supposant que ces dernières sont saisonnières. Sous cette hypothèse la qualité de la prévision annuelle s’améliore considérablement. Nous proposons aussi de prévoir la production d’énergie éolienne au cours des quatre saisons de l’année. L’utilisation du modèle fractal, nous permet de trouver une division ”naturelle” de la série de la vitesse du vent afin d’affiner l’estimation de la production éolienne en détectant les points de ruptures. Dans les deux derniers chapitres, nous donnons des outils statistiques de la détection des points de ruptures et d’estimation des modèles fractals
The wind energy, one of the most competitive renewable energies, is considered as a solution which remedies the inconveniences of the fossil energy. For a better management and an exploitation of this energy, forecasts of its production turn out to be necessary. The methods of forecasts used in the literature allow only a forecast of the annual mean of this production. Certain recent works propose the use of the Central Limit Theorem (CLT), under not classic hypotheses, for the estimation of the mean annual production of the wind energy as well as its variance for a single turbine. We propose in this thesis, an extension of these works in a wind farm by relaxation of the hypothesis of stationarity the wind speed and the power production, supposing that the latter are seasonal. Under this hypothesis the quality of the annual forecast improves considerably. We also suggest planning the wind power production during four seasons of the year. The use of the fractal model, allows us to find a "natural" division of the series of the wind speed to refine the estimation of the wind production by detecting abrupt change points. Statistical tools of the change points detection and the estimation of fractal models are presented in the last two chapters

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Pinson, Laura. "Analyse et représentation des épisodes de caniculaires en zones urbaines denses : de la durée à la conception d'un indice de dangerosité." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1061/document.

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Le GIEC (groupe d’expert Intergouvernemental sur l’Evolution du Climat) dans leur 4 ème rapport souligne que les villes européennes seront impactées par des épisodes caniculaires plus fréquents et plus intenses dû aux modifications climatiques ayant lieu au cours du XXI ème siècle. La ville, espace climatique particulier, sensiblement plus chaud que son espace environnant amplifie le phénomène de l’îlot de chaleur urbain (ICU). Pour la ville de Paris, les îlots de chaleur urbains peuvent dépasser de 8 à 10°C les températures relevées quelques kilomètres plus loin. Cet effet est d’autant plus néfaste lors de période caniculaire comme a connu la France en 2003, 2006, 2010 ou bien même en 2015. La connaissance sur le phénomène de la canicule nécessite de mettre en relation des données autant spatiales que temporelles afin de définir des zones à risques .Pour pouvoir simuler une canicule, le modèle SURFEX-TEB, conçu par Météo-France, CNRS, a été choisi. Il permet d’estimer la température en ville à partir de conditions climatiques des plus hautes atmosphères. Ces prévisions sont importantes notamment en période de canicule où les écarts de température entre la ville et sa banlieue peuvent dépasser 8C°. Le risque caniculaire, induit par les ICU, est complexe à appréhender et à représenter.Pour caractériser, appréhender et représenter la canicule, avec l’aide du modèle SURFEX-TEB, nous avons effectué une assimilation avec des mesures réalisées pendant la canicule de 2015 sur Paris. Cette assimilation met en évidence par exemple les phénomènes d’accumulation et l’impact des configurations des appartements sur les températures intérieures et extérieures. Nos différentes configurations ont permis de confirmer l’importance de considérer les températures intérieures lors de périodes caniculaires.Ce travail de recherche propose donc un éclairage spécifique et technique de la représentation des canicules. Son objectif est une meilleure représentation des canicules et l’estimation de leur dangerosité en fonction de la durée du phénomène, de son intensité et des caractéristiques urbaines et humaines. Des cartes décrivant la canicule et sa dangerosité sont mises en valeur grâce à l’élaboration d’un site web grand public.Les résultats de cette recherche soulèvent une interrogation sur les seuils de canicule. Ils soulignent l’importance d’introduire un seuil de canicule intérieur et démontrent le rôle de la configuration urbaine et en particulier des types d’habitation pour mieux prendre en compte la dangerosité des canicules et espérer mieux atténuer leurs effets
The IPCC (Intergovernmental Panel on Climate Change) in its 4th report underlines that the European cities will be impacted by more frequent and more intense scorching episodes due to the climatic modifications taking place during the XXIth century. Peculiar climatic areas, significantly hotter than their surroundings, cities amplify the phenomenon of the urban heat island (UHI). In the example of Paris, the urban islands of heat can exceed by 8°C to 10°C the temperatures measured a few kilometers away. This effect is all the more fatal as heat wave periods become more and more regular (2003, 2006, 2010, 2015). The knowledge on the heat wave phenomenon requires to put in relation spatial and temporal data so as to define high-risk areas.To be able to simulate a heat wave, the SURFEX-TEB model, designed by Météo-France, and CNRS, was chosen. It allows to estimate the temperature in town from weather conditions of the highest atmospheres. These forecasts are particularly important in heat wave periods where temperature differences between cities and suburban areas can exceed 8°C. The heat wave risk, resulting from the UHI, is complex to both understand and represent.To characterize, understand and represent the heat wave by the means of the SURFEX-TEB model, we made a data fusion with measures realized during the 2015 heat wave in Paris. This assimilation highlights, for instance, the accumulation phenomena and the impact of the apartments configuration on the inside and outside temperatures. Our various configurations allowed to confirm the importance of taking into account the internal temperatures during heat waves periods.This research thus proposes a specific and technical perspective of the heat waves representation. Its objectives are a better representation of heat waves and a sharper estimation of their dangerousness according to the phenomenon duration, its intensity and the urban and human features. Maps describing the heat wave and its dangerousness are highlighted thanks to the elaboration of a public Web site.The results of this research rise an interrogation on the thresholds of heat wave. They underline the importance to introduce an internal threshold of heat wave and demonstrate the role of the urban configuration, particularly the types of house. This should contribute to better take into account the dangerousness of heat waves and to improve the mitigation of their effects

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Nema, Otavio Marcos Scarpa. "Indice de proximidade ao colapso de Tensão baseado nas perdas de potencia ativa : investigação do potencial de utilização na analise de segurança em tempo real de sistemas eletricos." [s.n.], 1996. http://repositorio.unicamp.br/jspui/handle/REPOSIP/262008.

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Orientador: Carlos Alberto de Castro Jr
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: Neste trabalho propõe-se a utilização de um índice baseado nas perdas de potência ativa para a identificação de barras/áreas sujeitas ao colapso de tensão. O cálculo deste índice exige um esforço computacional equivalente a uma iteração de um fluxo de carga sendo, portanto, apropriado para aplicação na operação em tempo real de redes elétricas. O índice foi comparado com outros propostos na literatura e os resultados foram satisfatórios. Verifica-se o caráter adaptativo da determinação das áreas sujeitas ao colapso em função das mudanças nas condições de operação da rede. Mostra-se que o índice pode auxiliar o operador da rede na determinação de ações de controle visando a diminuição do risco de colapso. Finalmente, discute-se o potencial de utilização do índice na classificação de contingências com relação ao colapso de tensão na análise de segurança em tempo real de redes elétricas
Abstract: This work proposes the utilization of an index based on system power losses to identify buses/areas subjected to volt age collapse. The computation of this index requires the equivalent to one iteration of a power flow, being appropriate for the real time operation of power systems. The comparison of this index with others cited in the literature provided satisfactory results. The adaptive characteristics of the index as the power system operating conditions change are shown. It is also shown that the index can be an important aid to the operator in determining control actions aiming at decreasing the risk of volt age collapse. Finally it is discussed the utilization of the index to the contingency classification with respect the volt age collapse in the real time security analysis of power systems
Mestrado
Mestre em Engenharia Elétrica

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Ramos, José Ezequiel. "Universalização da energia elétrica através da tecnologia cabos pára-raios energizados (PRE)." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/86/86131/tde-22082010-114031/.

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A universalização da energia elétrica, como uma das principais políticas públicas de inclusão social, tem como desafio a escolha de alternativas tecnológicas capazes de conciliar os aspectos de viabilidade técnica e econômica. A Tecnologia cabos para-raios energizados (PRE), objeto de estudo desta tese, se insere neste contexto. Assim, este trabalho consiste na análise de viabilidade do PRE no esquema trifásico, cuja instalação é associada à linha de transmissão 230 kV do sistema de transmissão de Rondônia. São analisados os aspectos de seu desempenho técnico, operacional e econômico. No aspecto técnico é analisado o desempenho do sistema de aterramento quanto à resistência de terra, tensões de toque e de passo, além de análise da queda de tensão, desequilíbrio de tensão e capacidade de carregamento da instalação. A abordagem técnica é aprofundada após análise do desempenho operacional avaliado a partir da classificação das interrupções verificadas em mais de 180 meses de operação do Sistema PRE Rondônia. Em decorrência dessa avaliação, são obtidos índices operacionais de continuidade, analisados comparativamente em relação a outras alternativas tecnológicas, visando analisar a viabilidade da Tecnologia PRE. Uma das constatações resultantes da análise das causas das interrupções indica um elevado impacto das descargas atmosféricas no desempenho do PRE. Este aspecto é extensivamente analisado quanto aos efeitos das descargas diretas e indiretas sobre a instalação, partindo-se de medições de campo nos contrapesos das torres, medições de resistividade do solo e ensaios na cadeia de isoladores do PRE. Simulações são realizadas utilizando-se os programas computacionais ATPDraw, ERM e CDEGS para análise das tensões resultantes de descargas diretas, tensões induzidas por descargas indiretas e cálculo de resistência de terra, respectivamente. São investigados os efeitos de parâmetros importantes no desempenho do sistema frente a descargas atmosféricas e comparados os números de interrupções estimadas e verificadas em campo, partindo-se de um roteiro metodológico minuciosamente detalhado, a fim de permitir a repetição dos procedimentos em situações semelhantes às analisadas neste trabalho. Após uma análise comparativa do desempenho do sistema PRE em relação a outras alternativas convencionais, são estabelecidos índices de referência para o desempenho operacional da Tecnologia PRE e desenvolvida uma análise econômica da implantação dessa tecnologia em Rondônia.
As one of the major public policies of social inclusion, the universalization of electric energy services has as a challenge to choose appropriate technological solutions that combine technical and economic aspects. The energized shield wire line technology (SWL), subject of this thesis, is in this context. This study aims at evaluating the viability of the SWL technology (three-phase scheme) installed on a 230 kV transmission line in the State of Rondônia. The analysis covers its technical, operational, and economic performance. The former aspect considers the performance of the grounding system regarding the ground resistance and step and touch voltages, analysis of voltage drop, voltage unbalance and the load capacity of the installation. The technical issue is deeply held after the analysis of the system operational performance in Rondônia based on the classification of outages considering a period greater than 180 months. The operational indices that result from this evaluation are compared to those corresponding to other technology alternatives in order to evaluate the viability of SWL technology. The analysis of the causes of interruptions reveals that lightning has a significant impact on the SWL performance. Thus, an extensive analysis is carried out regarding the effects of direct and indirect strokes on the SWL, including field measurements (soil resistivity and tower footing resistance) and laboratory tests (determination of the positive and negative critical flashover overvoltages of insulator strings). Simulations are performed using computer programs of proved validity (ATPDraw, ERM, and CDEGS) for the analysis of lightning overvoltages resulting from direct and indirect strokes and for the calculation of ground resistance. The effects of important parameters on the system lightning performance are investigated and the estimated and observed frequencies of interruptions are compared. The applied methodological procedure is described in detail, to allow the method to be used in other cases similar to the situations examined on this study. After a comparative analysis of the performance of the SWL with respect to other conventional alternatives, reference indices for the operational performance of SWL Technology are set and an economic analysis of the SWL technology in Rondônia is carried out.

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Calleja, Gómez Héctor Manuel, de Lira Diana Carolina Sánchez, and González Martha Elva Agustina Campuzano. "RELACIÓN ENTRE CIRCUNFERENCIA ABDOMINAL E ÍNDICE DE MASA CORPORAL CON LOS NIVELES DE COLESTEROL TOTAL Y TRIGLICÉRIDOS EN LOS PACIENTES QUE ACUDEN AL CENTRO DE SALUD RURAL DISPERSO SANTA MARÍA LA ASUNCIÓN DE ENERO A DICIEMBRE 2012." Tesis de Licenciatura, Medicina-Quimica, 2013. http://ri.uaemex.mx/handle/123456789/14192.

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La obesidad y la dislipidemia son los principales factores de riesgo cardiovascular que presenta la población mexicana debido a una evidente predisposición genética y estilo de vida occidentalizado con dietas inadecuadas y sedentarismo. La prevalencia de estas entidades nosológicas va en aumento y se prevé continuarán incrementándose de no aplicar las medidas de salubridad necesarias para combatir esta epidemia. Objetivo: Conocer la relación existente entre la circunferencia abdominal y el índice de masa corporal con los niveles séricos de colesterol total y triglicéridos. Materia y Métodos: Estudio de corte transversal analítico que incluyó a 174 individuos, hombres y mujeres, entre 20 a 80 años. Se obtuvieron sus medidas antropométricas y niveles séricos de colesterol total y triglicéridos. Se uso una base de datos en el programa Excel XP y analizaron dichos datos con el programa SPSS 18. Resultados: La edad promedio fue de 39.85 años; 102 (58.62%) correspondían al sexo femenino. La prevalencia de hipertrigliceridemia fue de 43.10%, hipercolesterolemia 8.05%, obesidad central el 78.16% y sobrepeso/obesidad por índice de masa corporal el 77.57%. De los sujetos con circunferencia abdominal aumentada el 74.26% presentó algún tipo de dislipidemia, y el 53.44% presentó obesidad central asociada a hipertrigliceridemia. De los sujetos con índice de masa corporal mayor a 25 kg/m2 el 68.88% presentan hipertrigliceridemia. Conclusiones: La circunferencia abdominal aumentada presenta una importante asociación estadísticamente significativa con la hipertrigliceridemia (p=.007), al igual que el índice de masa corporal presenta una asociación estadísticamente significativa con la hipertrigliceridemia (p=.042); y tienen una alta prevalencia en la población estudiada.

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Wagner, Franziska [Verfasser]. "Genomic-morphological analysis of the rat and mouse habenulae uncovers a high molecular heterogeneity and indicates involvement in the regulation of feeding and energy balance / Franziska Wagner." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2017. http://d-nb.info/1126504181/34.

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Patiño, Pascumal Lourdes Isabel. "Estructura productiva, eficiencia energética y emisiones de CO2 en Colombia." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/400393.

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Esta tesis tiene como objetivo determinar y cuantificar la interrelación entre el consumo de energía, la actividad económica y las emisiones de CO2 en Colombia, en tres capítulos auto contenidos. En el primer capítulo, se analizan los factores determinantes de las emisiones de CO2 y la eficiencia energética durante el período 1971-2010. Para este propósito, se desarrollan dos descomposiciones utilizando el método del Índice Logarítmico Medio de Divisia: la primera, relacionada con las emisiones de CO2 basada en la identidad Kaya, y la segunda relacionada con el consumo de energía primaria por unidad de actividad económica, medida a nivel sectorial. Los resultados muestran que la intensidad energética es el principal factor que explica la disminución de las emisiones de CO2 y la mejora de la eficiencia energética. Los sectores que presentan las mayores reducciones en la intensidad energética son: el sector transporte y el sector industrial. En el último sector, el cambio estructural es favorable a la eficiencia energética. En el capítulo dos, se analiza la relación entre los dos indicadores de presión ambiental (emisiones de CO2 per cápita y el consumo de energía per cápita) y otras variables (como el PIB per cápita y la composición de la energía). También se examina la validez de la hipótesis de la curva de Kuznets ambiental (EKC) para estas presiones ambientales, y se estima la elasticidad ingreso de las emisiones de CO2 y la energía usando un método de simulación. Para lograr estos propósitos, se estiman dos modelos dinámicos de ajuste parcial, uno para las emisiones de CO2 y otro para la energía, ambos para el período 1971-2011. Los resultados sugieren la existencia de un EKC, con los puntos de inflexión de la energía en 2006 y las emisiones de CO2 en el año 2011. Estos patrones apuntan a una posible desvinculación del crecimiento económico y la presión del medio ambiente. Los resultados muestran que, los cambios en la composición de las fuentes de energía aumentan el ahorro de energía y la reducción de las emisiones de CO2. La elasticidad ingreso de energía y las emisiones, a lo largo del período presenta tendencia descendente, y cae a cero en el punto de inflexión de la EKC. En el tercer capítulo, se determinan los sectores clave del consumo de energía primaria, y se realiza un análisis de cambio estructural del consumo de energía primaria considerando los sectores económicos de Colombia, durante el período 1996-2010. Esto se logra, usando un modelo input-output con un enfoque de demanda, y otro enfoque alternativo, del uso de energía. El primer enfoque, muestra que el descenso en el consumo de energía primaria, se explica mejor por la tecnología, mientras que su incremento se explica por los cambios en los niveles de demanda. El segundo enfoque, reitera la importancia del cambio técnico en la reducción del consumo de energía, mientras que la demanda y el uso de la tecnología, dan cuenta del aumento en el consumo de energía. Las elasticidades sectoriales estimadas muestran que los sectores clave para el desarrollo de una política de conservación energética son: el transporte terrestre y los servicios.
This thesis aims to determine and quantify the relationship between energy consumption, economic activity and CO2 emissions in Colombia in three self-contained chapters. In chapter one, factors explaining trends in CO2 emissions and energy efficiency for the period 1971 to 2010 are analysed. For this purpose, two decompositions are developed using the Logarithmic Mean Divisia Index: one for CO2 emissions based on the Kaya identity, and another for primary energy consumption per unit of output or activity, measured at the sectorial level. Results show that energy intensity is the main factor explaining the decline in CO2 emissions and improvement in energy efficiency. Transport and manufacturing are the sectors with the largest reductions in energy intensity. Structural change in the latter sector also helps to improve energy efficiency. In chapter two, the relationship between two environmental pressure indicators (CO2 emissions per capita and per capita energy consumption) and other variables (such as per capita GDP and the composition of the energy) is analyzed. Moreover, the validity of the environmental Kuznets curve hypothesis (EKC) is tested for these environmental pressures. A simulation method is used to estimate the income elasticity of energy and CO2 emissions. For these purposes, two partial adjustment dynamic models are estimated for CO2 emissions and energy for the period 1971-2011. Results suggest the existence of an EKC, with turning points for energy in 2006 and for CO2 emissions in 2011. These patterns point to a possible de-linking of economic growth and environmental pressure. The result reveals that changes in the composition of energy sources has increased energy savings and reduced CO2 emissions. Throughout the period, the income elasticity of energy and emissions presents a downward trend and fall to zero at the turning point of the EKC. Chapter three, determines key sectors of primary energy consumption and analyses structural change in primary energy consumption in Colombian all sectors from 1995 to 2010. This is done using an input-output model applying demand and use of energy approaches. The first approach shows that technology best explains the decline in energy consumption, while its subsequent increase is explained by rises in demand. The second approach reiterates the importance of technical change in the reduction of energy consumption, while demand and the use of technology accounts for the increase in energy use. Estimated sectoral elasticities show that land transport and services are key sectors on which energy conservation policies should focus.

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Recuay, Arana Patricia Marleni. "El indice tobillo braquial y su asociación con el riesgo cardiovascular y la clasificación Wagner en pacientes diabéticos tipo 2, Hospital Nacional Guillermo Almenara Irigoyen : enero-marzo 2007." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2007. https://hdl.handle.net/20.500.12672/2514.

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Objetivo: Determinar la frecuencia de anormalidades del índice tobillo braquial (ITB) y su grado de asociación entre con el riesgo cardiovascular Framingham y la clasificación Wagner en los pacientes diabético tipo 2 de la Unidad de Pie diabético del Hospital Nacional Guillermo Almenara Irigoyen (HNGAI) durante el periodo Enero-Marzo 2007. Material y métodos: Se intervinieron prospectivamente todos los pacientes diabéticos tipo 2 que ingresaron a la Unidad de Pie Diabético del HNGAI durante periodo Enero-Marzo 2007 y se determinó la frecuencia de anormalidades del ITB así como la asociación entre el ITB, el riesgo cardiovascular Framingham (Riesgo FRAM) y la clasificación Wagner, calculándose sus respectivos índices de correlación (r de Pearson y rho de Spearman, según correspondan) y sus respectivos valores de p.
Objective: To determine the frequency of abnormalitys of the ankle-brachial index (ABI) and its degree of association between with the Framingham cardiovascular risk and the Wagner classification at the diabetic type 2 patients of the Diabetic Foot Unit of the Hospital Nacional Guillermo Almenara Irigoyen (HNGAI) during the January-March 2007 period. Method: All the referred diabetic type 2 patients to the HNGAI-Diabetic Foot Unit during January-March 2007 period were prospective intervened and the ABI abnormalitys frequency was determined as well as the association between the ABI, the Framingham cardiovascular risk (FRAM-risk) and the Wagner classification, calculating its respective correlation coefficients (r of Pearson and rho of Spearman, like its correspond) and its respective p values.
Tesis de segunda especialidad

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Salvi, Nicola. "Soluzioni impiantistiche plug-play per la riqualificazione energetica di edifici esistenti con addizioni volumetriche esterne." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

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L'obiettivo della Tesi di Laurea si inserisce tra quelli del progetto europeo ProGETonE, in particolar modo la riqualificazione energetica attraverso l'inserimento di impianti performanti e l'uso di fonti di energia rinnovabile al fine di ridurre al massimo i consumi energetici, fino ad arrivare ad avere un edificio NZEB. L'oggetto di intervento della Tesi di Laurea è un complesso residenziale in Provincia di Reggio Emilia di 13 appartamenti di edilizia popolare, nel quale è previsto un incremento di volumetria al fine di aumentarne il valore. É previsto inoltre l'inserimento di un isolamento a cappotto sulle pareti esterne esistenti e la sostituzione degli infissi. La tesi di Laurea parte da queste ipotesi progettuali e ha come fine quello di proporre diverse soluzioni impiantistiche di fattibilità, al fine di ottenere un miglioramento energetico. Nello stato di fatto è presente un impianto termico centralizzato per il riscaldamento degli ambienti e per la produzione di acqua calda sanitaria, con un generatore di calore alimentato a metano; non è presente nessuna forma di impianto di raffrescamento. Vengono proposte tre soluzioni che vanno ad evidenziare modalità diverse di intervento su un edificio esistente, ma in tutti i casi si ottiene un miglioramento in termini di riscaldamento invernale, raffrescamento estivo e qualità dell'aria interna all'abitazione. Per tutte tre le soluzioni è previsto l'inserimento di fonti di energia rinnovabile, ovvero pannelli fotovoltaici da collocarsi nel tetto; Il fine di questa tesi è quello di proporre soluzioni impiantistiche per il miglioramento energetico, i risultati sono stati valutati tramite simulazioni energetiche con il software EdilClima e confrontate con quelle svolte sullo stato di fatto e post intervento.

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Alcantara, Michael Steinhorst. "Biodigestão anaeróbia de cama de aviário com recirculação de digestato." Universidade Estadual do Oeste do Parana, 2016. http://tede.unioeste.br:8080/tede/handle/tede/247.

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Poultry farming has increased and so does the amount of residues from producing areas with poultry litter and dead broilers, consequently, there is a major environmental problem for the poultry industry. Poultry litter, rich in organic matter, commonly applied on soil without treatment, acidifies it by releasing hydrogen ions since it stabilizes organic matter and also because it is a nitrogen fertilizer. Therefore, other applications for poultry litter are needed and should be studied, as for example, its use for power generation by anaerobic digestion. This process is attractive for the sector by treating waste and generating biogas that may replace the energy used in poultry. There is, however, an environmental restriction to this system because it requires a large amount of water to hydrolyze poultry litter. Therefore, this study has evaluated the anaerobic digestion of poultry litter in a digester built with glass fiber boxes whose total volume was 40.0 m3. There was a system of effluent reuse from the digester to dilute its next feeding and reduce water consumption during this process. The effluent was reused with its recirculation at the feeding moment with a motor pump, in a semi-continuous system (once a day). The anaerobic digestion has been stabilized at the organic feeding charges of 0.5 and 1.0 kg total volatile solids by m3 digester, so, the evaluations 1 and 2 were created, respectively. There was a hydraulic retention time of 10 days for both evaluations. The stabilization process occurred by Shewhart charts while the process analysis occurred by the process capacity and operational energy viability of the system indexes. At the evaluation number 2, the process was capable and viable for power operations, whose energy production as methane was 4.41 times superior to the electric energy consumed on operations of the treating system, 0.0182 m3 methane kg-1 VTS-1added. The produced effluent was not characterized as an adequate biofertilizer for crop yield because it showed small amounts of nutrients content. On the other hand, the sludge is available as organic manure since a great amount of nutrients has sedimented on the bottom of the digester. At the final period, after evaluation number 2, the digester and motor pump did not present any adequate feeding flux due to the large content of solids in the effluent; so, it was not possible to operate the digester. However, pH (close to 7.00) and the ratio between volatile acidity and total alkalinity of the effluent (below 0.3) at the final period indicated that anaerobic digestion showed some potential to be continued. This fact highlights the importance of other studies about dilution of poultry litter mechanism on the effluent of digester
O crescimento da produção de frangos tem concentrado resíduos nas regiões produtoras, cama de aviário e aves mortas, gerando um grande problema ambiental para a indústria avícola. A cama de aviário, rica em matéria orgânica, comumente aplicada no solo sem tratamento, acidifica o mesmo por liberar íons de hidrogênio ao estabilizar sua matéria orgânica e por ser um fertilizante nitrogenado. Portanto, outras aplicações para a cama de aviário são necessárias e devem ser estudadas, como o seu uso para geração de energia pela biodigestão anaeróbia. Este processo é um atrativo para o setor por tratar o resíduo e gerar biogás que pode substituir a energia usada na criação dos frangos. Existe, porém, um entrave ambiental neste sistema por necessitar de grande quantidade de água para hidrolisar a cama de aviário. Por isso, esse trabalho avaliou a biodigestão anaeróbia da cama de aviário em um biodigestor construído com caixas de fibra de vidro no volume total de 40 m3 com sistema de reutilização do digestato do biodigestor na diluição da próxima alimentação, para reduzir o consumo de água no processo. O digestato foi reutilizado pela recirculação do mesmo no momento da alimentação do biodigestor com uma motobomba, em sistema semi-contínuo (uma vez ao dia). A biodigestão anaeróbia foi estabilizada nas cargas orgânicas de alimentação de 0,5 e 1,0 kg sólidos totais voláteis por m3 de biodigestor, para a construção das avaliações 1 e 2, respectivamente. O tempo de retenção hidráulica foi de 10 dias para as duas avaliações. A estabilização procedeu-se pelo gráfico de Shewhart e a análise do processo pelo índice de capacidade do processo e pelo índice de viabilidade energética operacional do sistema. Na avaliação 2, o processo se apresentou como capaz e viável nas operações energéticas, com produção de energia na forma de metano 4,41 vezes maior que a energia elétrica gasta nas operações do sistema de tratamento, sendo 0,0182 m3 metano kg-1 STV-1adicionados. O digestato produzido não se caracterizou como biofertilizante adequado para as culturas por ter pequeno teor de nutrientes. Porém, o lodo é aplicável como adubo orgânico devido à grande parte dos nutrientes ter sedimentado no biodigestor. No período final, após a avaliação 2, o biodigestor e a motobomba não apresentaram mais fluxo de alimentação devido à quantidade de sólidos no digestato e por este motivo, não se conseguiu mais operar o biodigestor. No entanto, o pH (próximo a 7,00) e a relação entre a acidez volátil e a alcalinidade total do digestato (abaixo de 0,3) no período final indicavam que a biodigestão anaeróbia tinha potencial para ser continuada. Tal fato ressalta a importância de outros estudos sobre mecanismos de diluição da cama de aviário no afluente do biodigestor.

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Sallaz-Damaz, Yoann. "Un imageur Cherenkov pour la mesure de charge des éléments du rayonnement cosmique nucléaire." Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00350021.

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Un imageur Cherenkov, CherCam (CHERenkov CAMera), a été développé et construit pour être intégré à l'expérience CREAM (Cosmic-Ray Energetic and Mass) embarquée en ballon. Cette instrument doit permettre de mesure le charge du rayonnement cosmique nucléaire allant du protron au fer dans une gamme d'énergie s'étendant de 1E10 à 1E15 eV.
La thèse s'est principalement orienté sur le développement de CherCam par la création d'une simulation et de la caractérisation du plan radiateur en aérogel de silice. Mais elle s'est aussi largement étendu sur les aspects technique par la construction du détecteur et ses différents tests, ainsi que par le développement des logiciel d'étalonnage et d'analyse.

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Possagnolo, Leonardo Henrique Faria Macedo. "Planejamento da expansão de sistemas de distribuição de energia elétrica considerando restauração do fornecimento /." Ilha Solteira, 2019. http://hdl.handle.net/11449/181600.

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Orientador: Rubén Augusto Romero Lázaro
Resumo: A grande maioria dos sistemas de distribuição de energia elétrica opera de forma radial. Isso significa que cada carga é alimentada por apenas uma subestação por meio de um único caminho. Entretanto, as redes de distribuição apresentam estrutura malhada, de forma que, caso uma contingência ocorra, o restabelecimento do fornecimento possa ser realizado para o maior número possível de consumidores. Os trabalhos que lidam com o problema de planejamento da expansão de sistemas de distribuição, no entanto, geralmente consideram a expansão do sistema para apenas uma topologia radial, sem levar em conta aspectos da restauração do fornecimento para melhoria dos índices de confiabilidade. Nesse contexto, este trabalho aborda o planejamento de sistemas de distribuição considerando aspectos econômicos e de confiabilidade, de forma a incluir a restauração do fornecimento no problema de planejamento da expansão. Na formulação do problema considera-se a expansão de novas subestações, o reforço de subestações existentes, a construção de novos alimentadores em novos caminhos, a troca de condutores existentes e a alocação de geradores distribuídos, além de expansão multiestágio e restauração do fornecimento para melhoria dos índices de confiabilidade. Dois métodos alternativos são propostos para resolver o problema descrito: o primeiro considera modelos matemáticos com diversos graus de precisão, para serem resolvidos por métodos exatos, e o segundo é uma meta-heurística de busca e vizinhança... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The vast majority of electricity distribution systems are operated radially. This means that each load is supplied by only one substation through a single path. However, distribution networks have a meshed structure so that, in the case of a contingency, the supply is restored to as many customers as possible. The works that deal with the distribution systems expansion planning problem, however, generally consider the expansion of the system for only one radial topology, disregarding the restoration aspects to improve reliability indices. In this context, this work deals with the planning of distribution systems considering economic and reliability aspects, to include the service restoration in the planning problem. In the formulation of the problem, it is considered the expansion of new substations, the reinforcement of existing substations, the construction of new feeders in new paths, the exchange of existing conductors, and the allocation of distribution generation, besides multistage expansion and service restoration to improve the reliability indices of the system. Two alternative methods are proposed to solve the described problem: the first one considers relaxed or approximated mathematical models to be solved by exact methods, and the second one is a variable neighborhood search metaheuristic, which solves the complete model for the problem approximately, without guarantee of optimality. The initial solution of the metaheuristic is generated by a strategy that constr... (Complete abstract click electronic access below)
Doutor

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Dortel, Emmanuelle. "Croissance de l'albacore (Thunnus albacares) de l'Océan Indien : de la modélisation statistique à la modélisation bio-énergétique." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20035/document.

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Depuis le début des années 1960, la croissance de l'albacore fait l'objet d'une attention particulière tant dans le domaine de la recherche que pour la gestion des pêcheries. Dans l'océan Indien, la gestion du stock d'albacores, sous la juridiction le Commission Thonière de l'Océan Indien (CTOI), souffre de nombreuses incertitudes associées à la courbe de croissance actuellement considérée. En particulier, des lacunes subsistent dans notre connaissance des processus biologiques et écologiques élémentaires régulant la croissance. Leur connaissance est pourtant fondamentale pour comprendre la productivité des stocks et leur capacité de résistance à la pression de pêche et aux changements océanographiques en cours. À travers la modélisation, cette étude se propose d'améliorer les connaissances actuelles sur la croissance de la population d'albacore de l'océan Indien et de renforcer ainsi les avis scientifiques sur l'état du stock. Alors que la plupart des études sur la croissance de l'albacore s'appuient sur une seule source de données, nous avons mis en œuvre un modèle hiérarchique Bayésien qui exploite diverses sources d'informations sur la croissance, i.e. des estimations d'âge obtenues par otolithométrie, des analyses de progressions modales et les taux de croissance individuels issus du marquage-recapture, et intègre explicitement des connaissances d'experts et les incertitudes associées à chaque source de données ainsi qu'au processus de modélisation. En particulier, le modèle de croissance a été couplé un à modèle d'erreurs dans les estimations d'âge par otolithométrie apportant une amélioration significative des estimations d'âge et des paramètres de croissance en résultant et permettant une meilleure évaluation de la fiabilité des estimations. Les courbes de croissances obtenues constituent une avancée majeure dans la représentation du patron de croissance actuellement utilisé dans les évaluations de stock d'albacore. Elles démontrent que l'albacore présente une croissance en phases, caractérisée par une forte accélération en fin de phase juvénile. Cependant, elles n'apportent aucune information sur les mécanismes biologiques et écologiques à l'origine de ces phases de croissance. Afin de mieux comprendre les facteurs impliqués dans l'accélération de la croissance, nous avons mis en œuvre un modèle bio-énergétique s'appuyant sur les principes de la théorie des bilans dynamiques d'énergie (DEB). Deux hypothèses apparaissant comme les plus pertinentes ont été testées : (i) une faible disponibilité alimentaire liée à une forte compétition inter et intra-spécifique chez les jeunes albacores formant des bancs et (ii) un changement dans le régime alimentaire des adultes s'accompagnant de la consommation de proies plus énergétiques. Il apparait que ces deux hypothèses sont susceptibles d'expliquer, au moins partiellement, l'accélération de la croissance
Since the early 1960s, the growth of yellowfin has been enjoyed a particular attention both in the research field and for fisheries management. In the Indian Ocean, the management of yellowfin stock, under the jurisdiction of the Indian Ocean Tuna Commission (IOTC), suffers from much uncertainty associated with the growth curve currently considered. In particular, there remain gaps in our knowledge of basic biological and ecological processes regulating growth. Their knowledge is however vital for understanding the stocks productivity and their resilience abilities to fishing pressure and oceanographic changes underway.Through modelling, this study aims to improve current knowledge on the growth of yellowfin population of the Indian Ocean and thus strengthen the scientific advice on the stock status. Whilst most studies on yellowfin growth only rely on one data source, we implemented a hierarchical Bayesian model that exploits various information sources on growth, i.e. direct age estimates obtained through otolith readings, analyzes of modal progressions and individual growth rates derived from mark-recapture experiments, and takes explicitely into account the expert knowledge and the errors associated with each dataset and the growth modelling process. In particular, the growth model was coupled with an ageing error model from repeated otolith readings which significantly improves the age estimates as well as the resulting growth estimates and allows a better assessment of the estimates reliability. The growth curves obtained constitute a major improvement of the growth pattern currently used in the yellowfin stock assessment. They demonstrates that yellowfin exhibits a two-stanzas growth, characterized by a sharp acceleration at the end of juvenile stage. However, they do not provide information on the biological and ecological mechanisms that lie behind the growth acceleration.For a better understanding of factors involved in the acceleration of growth, we implemented a bioenergetic model relying on the principles of Dynamic Energy Budget theory (DEB). Two major assumptions were investigated : (i) a low food availability during juvenile stage in relation with high intra and inter-specific competition and (ii) changes in food diet characterized by the consumption of more energetic prey in older yellowfin. It appears that these two assumption may partially explain the growth acceleration

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Borghi, Nicola. "Una nuova stima del parametro di Hubble a z ∼ 0.7 attraverso i cronometri cosmici." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/21447/.

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In questo lavoro di Tesi, è stata studiata una sonda cosmologica alternativa, i cronometri cosmici, per porre vincoli sul tasso di espansione dell'Universo a partire dai dati della survey LEGA-C. Il metodo dei cronometri cosmici consente di ottenere una misura diretta del parametro di Hubble H(z) studiando l'età differenziale di popolazioni omogenee di galassie, senza bisogno di dover assumere alcun modello cosmologico. Questo metodo viene implementato, per la prima volta in letteratura, attraverso lo studio degli indici spettrali di galassie passive individuali sfruttando l'ottima risoluzione R∼3500 e rapporto segnale-rumore S/N∼20 degli spettri della Data Release 2 della survey LEGA-C. 350 galassie massive e passive sono state estratte dal campione parente incrociando criteri spettro-fotometrici per massimizzarne la purezza. Tramite il metodo degli indici spettrali si estraggono età, metallicità stellare e arricchimento α delle popolazioni stellari di ogni singola galassia del campione. La combinazione di indici utilizzata (HδA, Ca4227, G4300, HγA, HγF, Fe4383, Fe4531, C4668) è stata scelta in seguito a un'analisi estensiva volta a massimizzare la robustezza dei risultati. Si derivano età di galassie comprese tra 2.5 e 5 Gyr, in ottimo accordo con l'età dell'Universo per una cosmologia ΛCDM standard. Inoltre, [Z/H] e [α/Fe] sono in accordo con i valori misurati nell'Universo locale e consistenti con un'evoluzione puramente passiva. Attraverso la relazione età-redshift mediana sono stati esplorati vincoli ai parametri cosmologici, ottenendo, per un universo ΛCDM piatto, una stima indipendente della costante di Hubble, H0=70.0^+28.7_-18.5 km/s/Mpc. Applicando il metodo dei cronometri cosmici, è stata derivata una nuova misura del parametro di Hubble, H(z=0.72) = 96.1 ± 35.1 km/s/Mpc, per la prima volta ottenuta tramite il metodo degli indici di assorbimento. Verifiche svolte con altre combinazioni di indici confermano l'attendibilità di questo risultato.

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Erdozia, Perez de Heredia Agurtzane, and Alessandro Ferraris. "Benefit and value of Li-Ion batteries in combination with largescale IRES : The case of solar PV in India and wind power in Sweden." Thesis, KTH, Elkraftteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214392.

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Li-ion batteries have demonstrated to be a very flexible source with energystorage capability. Due to their scalability and wide range of power and energydensities, they are suitable for several applications. Li-ion storage cantherefore provide different services, the remuneration of which depends onthe electricity market of the country. In this work, two different case studiesof combination of Li-ion batteries with large-scale renewable power plantshave been investigated: batteries with solar PV in India and with wind powerin Sweden. Simulation models have been developed to assess the operationand profitability potential of different services in these two case studies. Themodels have been built using control algorithms, linear optimization (LP) andstochastic programming techniques. The results show that the use of batteriesfor solar power output smoothing under a power purchase agreement canbe a profitable business case in India. Moreover, batteries providing primaryfrequency regulation (FCR-N) in Sweden show to have a positive economicvalue. System breakeven costs to make the stacking of wind power productionimbalance compensation and FCR-N services profitable have been found,which based on conservative price expectations should be achieved by 2022.
Li-ion batterier har visat sig vara en mycket effektiv källa för lagring av energi.Tack vare deras skalbarhet och det breda utbudet av kraft och energidensiteterhar de flera användningsområden. Li-ion batterier kan därför användas föratt tillhandahålla olika typer av tjänster vars ekonomiska ersättning beror avlandets elmarknad. Detta arbete undersöker två fallstudier av Li-ion batterieri kombination med storskaliga kraftverk som drivs av förnybara energikällor:batterier i kombination med solkraft i Indien och vindkraft i Sverige. Simuleringsmodellerhar utvecklats för att undersöka driften och lönsamhetspotentialenför olika tjänster i de två fallstudierna. Modellerna baserar sig påkontrollalgoritmer, linjär optimering och stokastisk programmeringsteknik.Resultaten visar att användningen av batterier för utjämning av solenergi enligtett kraftköpavtal kan vara lönsamma i Indien. Dessutom har användningenav batterier för primärreglering (FCR-N) visat sig ha ett positivt ekonomisktvärde i Sverige. Breakeven kostnaderna för att göra kombinationen av vindkraftsproduktionensbalanskompensering och FCR-N tjänster lönsamma harhittats, vilket ska uppnås senast år 2022 baserat på en konservativ prisprognos.

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BONNEFOY, Olivier. "Influence des cristaux d'hydrates de gaz ou de glace sur la perméabilité d'un milieu poreux." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2005. http://tel.archives-ouvertes.fr/tel-00009658.

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Анотація:

La première partie est une étude bibiographique. Nous étudions les conditions thermodynamiques de stabilité des hydrates dans un milieu bulk et la composition des phases solide et liquide. Nous décrivons ensuite les écoulements dans les milieux poreux. Enfin, nous fusionnons les deux approches en étudiant l'influence du confinement sur la stabilité des hydrates. Un champ offshore (Blake Ridge) et un champ on-shore (Mallik) sont décrits dans le détail. Ce dernier servira de base aux simulations numériques ultérieures.

La deuxième partie est consacrée aux expériences. Leur but est de mesurer la perméabilité d'un sédiment contenant des cristaux. Pour nous rapprocher des conditions géologiques naturelles, les cristaux sont réalisés en l'absence de phase gazeuse. Il s'avère que les hydrates se forment de manière très hétérogène dans le milieu poreux et ceci rend les mesures non représentatives. Nous pensons que ce résultat est général et qu'à l'échelle de temps du laboratoire, la formation d'hydrates de gaz répartis uniformément dans un milieu poreux est très difficile. Pour contourner cette difficulté, nous montrons de manière théorique que les cristaux de glace ont un comportement analogue aux cristaux d'hydrate (du point de vue des forces de Van der Waals qui gouvernent l'agglomération). Ceci nous permet de calculer la constante de Hamaker des hydrates. La deuxième série d'expériences s'intéresse donc à la perméabilité d'un milieu poreux non consolidé et sous contrainte dont les pores sont occupés par des cristaux de glace. Deux populations de grains de silice sont utilisées pour former le milieu poreux : 3 mm et 200 microns. Avec les gros grains, les résultats font apparaître deux seuils : pour des saturations plus faibles que le seuil inférieur, la présence des cristaux n'affecte pas la perméabilité. Pour des saturations plus grandes que le seul supérieur, la perméabilité est quasiment nulle (phénomène de percolation). Entre les deux, la perméabilité décroît exponentiellement en fonction de la saturation. Avec les grains fins, la perméabilité décroît avec la même vitesse.

La dernière partie est une étude numérique sur le champ Mallik. Après avoir posé les équations décrivant les transferts massiques et de chaleur dans l'espace et au cours du temps, nous étudions un cas limite unidimensionnel. Ceci nous permet de voir l'influence de la courbe 'Perméabilité = f(saturation)' obtenue expérimentalement sur la quantité de gaz produite. Le code proposé permet également d'évaluer différents scénarios de production, dont la dépressurisation assistée par formation de glace.

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Peikriszwili, Tartaruga Marcus. "L'influence allométrique dans les relations entre économie de course, rendement mécanique et performance chez des athlètes de longue distance : efficience métabolique et prédiction de la performance en course a pied de longue distance." Phd thesis, Université Nice Sophia Antipolis, 2013. http://tel.archives-ouvertes.fr/tel-00926761.

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Анотація:

Le but de cette thèse était d'analyser la relation entre l'économie de course à pied (ECO) et l'efficiencemécanique (Eff) dans la performance des coureurs spécialistes en moyenne et longue distance, utilisantdes modèles allométriques. Basé dans les résultats de trois études originales, nous avons conclu quel'échelle allométrique peut améliorer la relation entre ECO et performance dans la course à pied demoyenne et longue distance, principalement en coureurs amateurs, pour raison morpho-fonctionnelles.Également, pour cette même population, des travaux mécaniques, principalement le externe, peut êtreconsidérées comme prédicteurs de la performance de la course à pied de sujets spécialistes en longuedistance, et un exposant allométrique peut améliorer cette prédiction. En ce qui concerne à l'Eff, lesrésultats ont montré que cette variable est, aussi, une important variable de prédiction de laperformance. Toutefois, quand appliqué des exposant allométriques, il n'y avait aucune améliorationdans cette prédiction, principalement en coureurs de haut niveau. Les résultats ont montré, aussi, quepour le calcul de l'Eff, la contribution de la dépense énergétique anaérobie est important, parce que,contrairement, les résultats peuvent être surestimés. En général, lorsque l'objectif est prédit laperformance des coureurs amateurs de moyenne ou de longue distance, à travers des puissancesmétaboliques ou mécaniques, est suggéré d'adopter un exposant allométrique spécifique du groupeétudié. Toutefois, lorsque cette prédiction est réalisée avec la utilisation de l'Eff en un groupe decoureurs de haut niveau, l'échelle allométrique n'est pas indiquée.

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Butarbutar, Sofia Loren. "Monte Carlo simulation of the radiolysis of water by fast neutrons at elevated temperatures up to 350°C." Mémoire, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/5887.

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Анотація:

Résumé : Le contrôle de la chimie de l'eau dans un réacteur nucléaire refroidi à l'eau nécessite une compréhension détaillée des effets de la radiolysede l'eau afin de limiter la corrosion et la dégradation des matériaux par oxydation générée par les produits de cette radiolyse. Toutefois, la mesure directe de la chimie dans le cœur des réacteurs est extrêmement difficile, sinon impossible, en raison des conditions extrêmes de haute température et haute pression, et les champs d’irradiation mixtes neutrons/γ, qui ne sont pas compatibles avec l'instrumentation chimique normale. Pour ces raisons,des modèles théoriques et des simulations sur ordinateur sont essentielles pour la prédiction de la chimie sous rayonnement de l'eau de refroidissement dans le cœur et son impact sur les matériaux. Dans ce travail, des simulations Monte Carlo ont été utilisées pour calculer les rendements des principales espèces (e[indice supérieur -][indice inférieur aq], H[indice supérieur •], H[indice inférieur 2], [indice supérieur •]OH et H[indice inférieur 2]O[indice inférieur 2]) formées lors de la radiolyse de l’eau liquide neutre par des neutrons mono-énergétiques de 2 MeV à des températures entre 25 et 350 °C. Le choix des neutrons de 2 MeV comme énergie d'intérêt est représentatif du flux de neutrons rapides dans un réacteur. Pour l'eau légère, la contribution la plus significative à la radiolyse vient des quatre premières collisions des neutrons qui produisent, dans la majorité des cas, des protons avec des énergies de recul de ~1.264, 0.465, 0.171 et 0.063 MeV et des transferts d’énergie linéique (TEL) moyens respectivement de ~22, 43, 69et 76 keV/[micro]m. Par ailleurs, nous avons négligé les effets des radiations dus aux ions de recul de l’oxygène. Les rendements moyens finaux peuvent alors être estimés comme étant la somme des rendements résultant de l’action de ces protons après pondérations en fonction de l’énergie déposée. Les rendements ont été calculés à 10[indice supérieur -7], 10[indice supérieur -6] et 10[indice supérieur -5] s. Les valeurs obtenues sont en accord avec les données expérimentales disponibles. En comparant nos résultats avec les données obtenues pour les rayonnements à faible TEL (rayons γ de [indice supérieur 60]Co ou électrons rapides), nos rendements calculés pour les neutrons rapides ont montré une dépendance en température essentiellement similaire, mais avec des valeurs plus faibles pour les rendements en radicaux libres et des valeurs plus élevées pour les rendements moléculaires. Nous avons également utilisé les simulations Monte Carlo pour étudier l'existence de la chute rapide de la constante de vitesse de réaction de l'électron hydraté (e[indice supérieur -][indice inférieur aq]) sur lui-même – l’une des principales sources de formation de H[indice inférieur 2] – au-dessus de 150 °C. Cette dépendance en température a été observée expérimentalement en milieu alcalin par divers auteurs, mais jamais en milieu neutre. Lorsque cette baisse de la constante de vitesse d’auto-réaction de e[indice supérieur -][indice inférieur aq] est incluse dans nos codes de simulation, tant pour des rayonnements de bas TEL (grappes isolés) que de haut TEL (trajectoires cylindriques), g(H[indice inférieur 2]) montre une discontinuité marquée à la baisse à ~150°C, ce qui n'est pas observée expérimentalement. Les conséquences de la présence de cette discontinuité dans le rendement en H[indice inférieur 2] pour les rayonnements à bas et haut TEL sont discutées. Enfin, nous avons tenté d’expliquer l'augmentation – considérée comme anormale – du rendement en H[indice inférieur 2] en fonction de la température au-dessus de 200 °C par l’intervention de la réaction des atomes H[indice supérieur •] avec l'eau, préalablement proposée par Swiatła-Wojcik et Buxton en 2005. La constante de vitesse de cette réaction est toujours controversée. // Abstract : Controlling the water chemistry in a water-cooled nuclear power reactor requires understanding and mitigating the effects of water radiolysis to limit the corrosion and degradation of materials by oxidizing radiolysis products. However, direct measurement of the chemistry in reactor cores is extremely difficult due to the extreme conditions of high temperature, pressure, and mixed neutron/γ-radiation fields, which are not compatible with normal chemical instrumentation. For these reasons, theoretical models and computer simulations are essential for predicting the detailed radiation chemistry of the cooling water in the core and the impact on materials. Monte Carlo simulations were used to calculate the yields for the primary species (e[superscript -][subscript aq], H[superscript •], H[subscript 2], [superscript •]OH, and H[subscript 2]O[subscript 2]) formed from the radiolysis of neutral liquid water by mono-energetic 2-MeV neutrons and the mechanisms involved at temperatures between 25 and 350 °C. In this work, we chose 2-MeV neutron as our energy of interest since it is known as representative of a fast neutron flux in a nuclear reactor. For light water, for that chosen energy, the most significant contribution to the radiolysis comes from the first four neutron collisions that generate mostly ejected protons with energies of ~1.264, 0.465, 0.171, and 0.063 MeV, which had, at 25 °C, mean linear energy transfers (LETs) of ~22, 43, 69, and 76 keV/[micro]m, respectively. In this work, we simply neglected the radiation effects due to oxygen ion recoils. The average final fast neutron yields could be estimated as the sum of the yields for these protons after allowance was made for the appropriate weightings (by using the Eq (2) in Chapter 4) according to their deposited energy. Yields were calculated at 10[superscript -7], 10[superscript -6] and 10[superscript -5] s. Our computed yield agreed reasonably well with the available experimental data. By comparing our results with data obtained for low-LET radiation ([superscript 60]Co γ-rays or fast electrons), our computed yields for fast neutron radiation showed essentially similar temperature dependences over the range of temperature studied, but with lower values for yields of free radicals and higher values for molecular yields. In this work, we also used our Monte Carlo simulation to investigate the existence of drop of hydrated electron (e[superscript -][subscript aq]) self-reaction rate constant at 150 °C. One of the main sources of H[subscript 2] formation is the self-reaction of hydrated electrons. The temperature dependence of the rate constant of this reaction (k[subscript 1]), measured under alkaline conditions, reveals that the rate constant drops abruptly above ~150 °C. However, when this drop in the e[superscript -][subscript aq] self-reaction rate constant is included in our code for low (isolated spurs) and high (cylindrical tracks) linear energy transfer (LET), g(H[subscript 2]) shows a marked downward discontinuity at ~150 °C which is not observed experimentally. The consequences of the presence of this discontinuity in H[subscript 2] yield for both low and high LET radiation are discussed. Another reaction that might explain the anomalous increasing of H[subscript 2] yield with temperature is the reaction of H[superscript •] atoms with water previously proposed by Swiatla-Wojcik and Buxton (2005) whose rate constant is still in controversial.

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