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Orientador: Celso Eduardo Tuna / Resumo: Com a criação de combustíveis alternativos para a redução de emissões de CO2 no setor aeronáutico, torna-se necessária a determinação de suas propriedades de segurança e, entre elas destacam-se os limites de inflamabilidade. O combustível alternativo aeronáutico, que é utilizado neste trabalho, é o farnesano, fabricado a partir da cana de açúcar, por um processo que transforma açúcar em hidrocarboneto, pela empresa Amyris, localizada em São Paulo, Brasil. O objetivo dessa dissertação é determinar experimentalmente os limites de inflamabilidade, inferior (LII) e superior (LSI) do farnesano, QAV e misturas de 10% (F10) e 50 % (F50) em massa de farnesano com o QAV a pressões reduzidas em ar. Utiliza-se uma bancada experimental, que segue a norma americana ASTM E681, para a determinação dos limites de inflamabilidade, em que se utiliza o critério visual de propagação de chama e um recipiente de vidro borosilicatado de 20,716 L. Primeiramente são determinados os limites de inflamabilidade dos combustíveis para a pressão de 101,3 kPa em temperaturas entre 140 e 220°C, comparando-se os resultados com os valores teóricos disponíveis na literatura para a validação do procedimento experimental. Em segundo lugar, são determinados os limites de inflamabilidade das amostras a pressões reduzidas como 80, 60, 40 e 20 kPa em temperaturas entre 140 e 200°C. Foram realizados, no total 636 testes para determinação dos limites de inflamabilidade, sendo a duração média, para cada teste de 20 minu... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The creation of alternative fuels to reduce CO2 emissions from the aeronautical sector needs determination of their safety properties, among which are flammability limits. farnesane is the alternative aviation fuel used in here, which has been produced from sugar cane through a conversion process known as direct sugar to hydrocarbon (DSHC) created by a company called Amyris, which is located in São Paulo, Brazil. Thereby, it is aimed to experimentally determine the flammability limits, lower (LFL) and upper (UFL) of farnesane, Jet fuel and mixtures of 10% (F10) and 50% (F50) in mass of farnesane at reduced pressures with air. For such a purpose, an experimental bench was built in accordance with American standard ASTM E681 to determine the lower flammability limits, in which flame propagation was analyzed visually through a 20.716 L borosilicate glass flask. The Flammability Limits of the fuels were initially determined at a pressure of 101.3 kPa and temperatures ranging between 140 and 220 ° C, whose results were compared with theoretical values found in literature in order to validate the experimental procedure. Afterwards, the Flammability Limits of samples were determined at reduced pressures, i.e. 80, 60, 40 and 20 kPa, and temperatures ranging between 140 and 200 ° C. 636 tests were performed altogether, the average time of each test was 20 minutes. Finally, prediction equations of flammability limits, were presented as a function of temperature / Mestre

Desenvolvemos uma estratégia natural e acessível aos estudantes do Ensino Médio para o cálculo de áreas planas sem as ferramentas mais avançadas do Cálculo Diferencial e Integral. / We developed a natural strategy, achievable by high school students, for the computation of area of limited regions of the cartesian plane, without making use of more advanced resources of Differential and Integral Calculus.

Made available in DSpace on 2016-03-15T19:34:16Z (GMT). No. of bitstreams: 1 Ana Paula Cordeiro Duarte.pdf: 1288409 bytes, checksum: d923d06618c082ca62d8fa3f216f68dc (MD5) Previous issue date: 2015-02-10 / This research deals with the limits of the powers of the National Electric Energy Agency ANEEL as authority regulator, in view of the possibility of existence of conflict or divergent decisions on the grounds of the tasks conferred to ANEEL, the other public entities of Public Administration Public indirect and direct. For this purpose, sought to analyze the reasons for the emergence of regulation in Brazil, the rise of regulatory agencies and the purpose for which these ones were created and their development. It also sought to understand the functions performed by regulatory agencies in the exercise of their activities and structure of the electricity sector and the consequent adjustment of the sector and creation of ANEEL, as well as the functions, key activities and assignments of that entity. Finally, a few assignments were analyzed by ANEEL, whose limits are questioned in order to be assignments similar to other ones, which could generate a conflict or divergent decisions on the exercise of the activities and performance of these ones. / A presente pesquisa trata dos limites das atribuições da Agência Nacional de Energia Elétrica ANEEL como ente regulador, tendo em vista a possibilidade de existência de conflito ou decisões divergentes em razão das atribuições conferidas à ANEEL, a outros entes públicos da Administração Pública Indireta e à Administração Pública Direta. Para tanto, buscou-se analisar as razões para o surgimento da regulação no Brasil, o surgimento das agências reguladoras e os objetivo pelos quais referidos entes foram criados e o seu desenvolvimento. Buscou-se, ainda, entender as funções desempenhadas pelas agências reguladoras no exercício de suas atividades e a estruturação do setor elétrico com a consequente regulação do setor e criação da ANEEL, bem como as funções, principais atividades e as atribuições do referido ente. Por fim, foram analisadas algumas atribuições da ANEEL, cujos limites são questionados, tendo em vista serem atribuições similares a de outros entes, o que poderia gerar ou não um conflito ou decisões divergentes no exercício das atividades e atuação desses entes.

Dans cette thèse, nous nous intéressons à l’analyse mathématique théorique et numérique des équations deNavier-Stokes compressibles en régime barotrope. La plupart des travaux présentés ici combinent desméthodes d’analyse des équations aux dérivées partielles et des méthodes d’analyse numérique afin de clarifierla notion de solution faible ainsi que les mécanismes de convergence de méthodes numériques approximant cessolutions faibles. En effet les équations de Navier-Stokes compressibles sont fortement non linéaires et leuranalyse mathématique repose nécessairement sur la structure de ces équations. Plus précisément, nousprouvons dans la partie théorique l’existence de solutions faibles pour un modèle d’écoulement compressibled’entropie variable où l’entropie du système est transportée. Nous utilisons les méthodes classiques permettantde prouver l’existence de solutions faibles aux équations de Navier-Stokes compressibles en regime barotrope.Nous étudions aussi dans cette partie la réduction de dimension 3D/2D dans les équations de Navier-Stokescompressibles en utilisant la méthode d’énergie relative. Dans la partie numérique nous nous intéressons auxestimations d’erreur inconditionnelles pour des schémas numériques approximant les solutions faibles deséquations de Navier-Stokes compressibles. Ces estimations d’erreur sont obtenues à l’aide d’une versiondiscrète de l’énergie relative satisfaite par les solutions discrètes de ces schémas. Ces estimations d’erreur sontobtenues pour un schéma numérique académique de type volumes finis/éléments finis ainsi que pour le schémanumérique Marker-and-Cell. Nous prouvons aussi que le schéma Marker-and-Cell est inconditionnellement etuniformément asymptotiquement stable en régime bas Mach. Ces résultats constituent les premiers résultatsd’estimations d’erreur inconditionnelles pour des schémas numériques pour les équations de Navier-Stokescompressibles en régime barorope. / In this thesis, we deal with mathematical and numerical analysis of compressible Navier-Stokes equations inbarotropic regime. Most of these works presented here combine mathematical analysis of partial differentialequations and numerical methods with aim to shred more light on the construction of weak solutions on oneside and on the convergence mechanisms of numerical methods approximating these weak solutions on theother side. Indeed, the compressible Navier-Stokes equations are strongly nonlinear and their mathematicalanalysis necessarily relies on the structure of equations. More precisely, we prove in the theorical part theexistence of weak solutions for a model a flow of compressible viscous fluid with variable entropy where theentropy is transported. We use the classical techniques to prove the existence of weak solutions for thecompressible Navier-Stokes equations in barotropic regime. We also investigate the 3D/2D dimensionreduction in the compressible Navier-Stokes equations using the relative energy method. In the numerical wedeal with unconditionally error estimates for numerical schemes approximating weak solutions of thecompressible Navier-Stokes equations. These error estimates are obtained by using the discrete version of therelative energy method. These error estimates are obtained for a academic finite volume/finite element schemeand for the Marker-and-Cell scheme. We also prove that the Marker-and-cell scheme is unconditionally anduniformly asymptotically stable at the Low Mach number regime. These are the first results onunconditionally error estimates for numerical schemes approximating the compressible Navier-Stokesequations in barotropic regime.

This dissertation investigates food safety regulations and international trade of agricultural products dividing into three aspects: the signalling effect from U.S. strict food safety regulations on U.S. vegetable exports, political determinants of sanitary and photosanitary non-tariff barriers, and the impact of trade barriers on employment in developing countries. In chapter 2, we investigate the impact of high U.S. maximum residue limit (MRL) standards on U.S vegetable exports to 102 countries utilizing the hierarchical model. MRL, which is one of non-tariff barriers with respect to food safety, is applied to home and foreign countries at the same time. Thus, firms in countries with higher food safety standards are expected to have a competitive advantage from the ‘signalling effect’. The results show that high MRL standards in the U.S. have a positive impact on U.S. vegetable exports, indicating the ‘signalling effect’ from the strict U.S. domestic MRL standards. The results provide policy makers with insights into how strict food safety regulations of the home country can be considered as a catalyst for increasing competitiveness in international markets. In chapter 3, we examine the political determinants of SPS notifications using a nonlinear threshold model with possible threshold variables (GDP per capita and tariff rate). This article finds no threshold values in both variables of GDP per capita and tariff rate. Our results also show that GDP per capita has a positive relationship with SPS notifications that are one of proxy variables for food quality. That implies the importance of quality competition in agriculture and food sectors. Our finding also represents no significant effect of tariff on SPS notifications. This indicates that a law of constant protection, presenting an inverse relationship between tariff and non-tariff barriers, is not satisfied in the agricultural and food sectors. In chapter 4, we investigate the impact of tariff and SPS barriers on food manufacturers’ skilled and unskilled employment in developing countries utilizing a structural equation model. Results show that both tariff and SPS barriers have a positive effect on unskilled labor employment in developing countries, while trade barriers are not associated with skilled labor employment. This implies that Hecksher-Ohlin theory, presenting labor abundant countries have a comparative advantage in labor-intensive industries such as food, explains well our results since developing countries are abundant in low-skilled labor. We also find that the age of food firm in developing countries is positively related to skilled employment; however, no relationship with unskilled employment. This implies that older food firms change their production process from labor intensive to capital or machine intensive.

This dissertation aims to determine what should be the appropriate base ethical limits of health care markets in the United States. I argue that because we do not value health care goods and services as commodities, treating them as commodities available for market sale can only be ethical when health care markets accord with at least the principles of honesty, respect for autonomy, and increased access to essential health care goods and services. I begin by establishing the theoretical foundation of my argument by expositing three theories of commodification and ethical markets that critically examine the relationship of goods to the market. Each theory shows how commodification often fails to account for the non-market value(s) we attribute to many goods. I then apply these theories to health care goods and services to show how they are not properly valued merely as commodities, and to lay the foundation of my argument regarding the ethical limits of health care markets. I then argue why honesty, respect for autonomy, and increased access to essential health care goods and services should be considered the base ethical limits of health care markets by examining how each ideally applies to both health care and the market. Lastly, I apply my argument to two health care markets: the pharmaceutical industry and a possible legal organ market. For the former, I show how many of the practices of the pharmaceutical industry violate what I argue should be the base ethical limits of health care markets. For the latter, I show the extent to which a legal organ market in the United States could or would violate these limits.

The object of this dissertation is to describe the opinions about the limits of natural science in their social and cultural context There exist two antagonistic positions to this matter restrictionism and expansionism. Restrictionism assumes that the natural sciences have no influence on metaphysics. Expansionism, on die other hand, argues that the natural sciences can legitimise the positions of beliefs and values. During the 1870b a restrictionist attitude on scientific knowledge established itself among influential German and British scientists. Emil Du Bois-Reymond, Rudolf Virchow, Hermann von Helmholtz and Thomas Henry Huxley were some of the famous scientists who rejected attempts to adduce science in religious and metaphysical matter. This restrictionism was rejected by other scientists and philosophers who believed that the modern natural sciences constituted a complete Weltanschauung, hostile to obsolete Christianity and philosophy. The thesis primarily deals with the debate on the limits of scientific knowledge in Sweden. We follow the development of the discussion from the 1870's to the years after the First World War. At the end of the 19th century Swedish scientists freed themselves from dominant natural philosophy and natural theology. Restrictionism was later on supported, in different ways, by recognized scientists, theologians, conservative critics, and philosophers. At the turn of the centuiy the restrictionist view of science was turned against metaphysical materialism, monism, naturalism, and an emergent, radical counter-culture. The controversies continued as long as the mechanical world picture dominated the natural sciences. With social and cultural changes, and the new physics of Rutherford, Einstein, Bohr, and Heisenberg, the debate slowly faded. / digitalisering@umu

Reliable results are crucial when working with medical decision support systems. A decision support system should be reliable but also be interpretable, i.e. able to show how it has inferred its conclusions. In this thesis, the preprocessing perceptron is presented as a simple but effective and efficient analysis method to consider when creating medical decision support systems. The preprocessing perceptron has the simplicity of a perceptron combined with a performance comparable to the multi-layer perceptron. The research in this thesis has been conducted within the fields of medical informatics and intelligent computing. The original idea of the production line as a tool for a domain expert to extract information, build decision support systems and integrate them in the existing system is described. In the introductory part of the thesis, an introduction to feed-forward neural networks and fuzzy logic is given as a background to work with the preprocessing perceptron. Input to a decision support system is crucial and it is described how to gather a data set, decide how many and what kind of inputs to use. Outliers, errors and missing data are covered as well as normalising of the input. Training is done in a backpropagation-like manner where the division of the data set into a training and a test set can be done in several different ways just as the training itself can have variations. Three major groups of methods to estimate the discriminance effect of the preprocessing perceptron are described and a discussion of the trade-off between complexity and approximation strength are included. Five papers are presented in this thesis. Case studies are shown where the preprocessing perceptron is compared to multi-layer perceptrons, statistical approaches and other mathematical models. The model is extended to a generalised preprocessing perceptron and the performance of this new model is compared to the traditional feed-forward neural networks. Results concerning the preprocessing layer and its connection to multivariate decision limits are included. The well-known ROC curve is described and introduced fully into the field of computer science as well as the improved curve, the QROC curve. Finally a tutorial to the program trainGPP is presented. It describes how to work with the preprocessing perceptron from the moment when a data file is provided to the moment when a new decision support system is built.

Invasive non-indigenous species are among the principle drivers of global change, altering nutrient cycles, changing disturbance regimes, and generally threatening biodiversity. Climate change is widely expected to exacerbate invasions by relaxing abiotic barriers, such as low temperature, but the mechanistic evidence supporting this is limited. Here, I evaluate the hypothesis that low temperatures determine the northern range limit of kudzu (Pueraria montana var. lobata), an invasive Asiatic vine in North America, by assessing freezing and chilling tolerance of kudzu plants in winter, spring, summer, and fall. Kudzu was widely planted throughout the southeastern U.S. in the early 20th Century to prevent erosion. It is winter-deciduous and reproduces primarily from buds on stem nodes. In the last 40 years, kudzu has migrated northward in concert with a northward shift in the -20oC minimum winter temperature isocline, indicating that less severe winter cold is permitting northward migration. Freezing mortality during winter does not explain this correlation. Electrolyte leakage assays demonstrate that above- and belowground kudzu stems can survive to -27oC and -17oC. Insulation provided by soil and snow protects belowground stems from lethal temperatures to well north of kudzu's current range limit. Severe spring chill stops growth and photosynthesis and causes some shoot mortality, but both growth and photosynthesis recover quickly following the chill. Summer growth rates are rapid (up to 22 cm/d), responding within hours to temperature changes, and are unimpaired by nighttime lows. Photosynthesis is reduced at cool temperatures, but on cool days, kudzu leaves tend to be warmer than air temperature, so photosynthesis rates generally remain close to optimal values. In autumn, growth stops below 15oC, but leaves are retained and maintain modest photosynthetic competence until killed by frost in November. In colder climates that occur far north of kudzu's current range, reductions in the length and quality of the growing season could accumulate over time to reduce kudzu's success. There is, however, no strong evidence that low temperatures in any season will prevent kudzu from migrating throughout southern Ontario, making kudzu a good candidate for invasive species regulations.