Les propriétés mécaniques des ciments hydratés nécessitent d'être optimisées suivant la nature des ciments produits. Parmi les facteurs d'optimisation, l'ajout de sulfate de calcium destiné à réguler la réactivité de l’aluminate tricalcique (C3A), en quantité et en qualité, dans le ciment est un paramètre primordial. Enjeu industriel majeur, cette notion d'Optimum de sulfatage mérite aujourd'hui du fait de l'avancement des connaissances sur les mécanismes d'hydratation de chacune des phases du ciment qu'une étude lui soit entièrement consacrée. La démarche adoptée pour répondre à cette problématique a été l’étude de système simple que l’on a compliqué petit à petit. L’évolution de l’hydratation du ciment, de la porosité et des propriétés mécaniques du ciment ont été déterminés à différentes échéances. Le premier système étudié était le mélange C3S/gypse, l'objectif était de déterminer s'il existait un effet optimal du sulfate de calcium sur l'hydratation et les résistances mécaniques du C3S tel que présenté dans la littérature [1]. Les résultats ont montré qu’il n’existait pas d’optimum de sulfatage dans le système C3S/gypse mais qu’il existait un effet spécifique du sulfate de calcium sur l’hydratation et les propriétés mécaniques du C3S. L’adsorption des sulfates à la surface des C-S-H serait à l’origine de la modification du processus de germination croissance des C-S-H qui aurait pour conséquence l’augmentation du degré d’hydratation du C3S et des résistances en compression. Le deuxième système étudié était le clinker biphasique C3S/C3A cobroyé avec du semi-hydrate et avec du gypse. Un optimum de sulfatage a bien été observé, cet optimum se décale avec le temps vers les fortes teneurs en sulfate comme dans les cimenteries. L’optimum de sulfatage a été constaté lorsque l’hydratation du C3S, pendant la période accélérée, a lieu simultanément ou légèrement avant le pic exothermique dû à la forte dissolution du C3A et à la précipitation d’Afm. Il a été montré que la présence d’AFm pendant la période accélérée de l’hydratation du C3S, serait à l’origine de la modification observée de la microstructure de la pâte de ciment : la porosité augmente avec l’ajout du sulfate de calcium mais l’assemblage des hydrates est plus dense / The mechanical properties of hydrated cements need to be optimized according to the nature of cement products. Among the factors of optimization, the addition of calcium sulphate intended to regulate the reactivity of tricalcium aluminate (C3A), in quantity and quality in cement is an essential parameter.The advancement of knowledge on the mechanisms of hydration of each cement phase allows a study devoted entirely to the concept of optimum of sulphate. We studied simple system that we complicated and we studied the evolution of hydration, porosity and mechanical properties of cement at different age. The first system studied was the mixture C3S/gypsum, the objective was to determine whether there was an optimal effect of calcium sulfate on hydration and mechanical strength of C3S as presented in the literature [1]. The results showed there was not optimum sulfate in the C3S/gypsum system but there was a specific effect of calcium sulfate on the hydration and the mechanical properties of C3S. The sulfate adsorption on the C-S-H surface is the cause of the change nucleation and growth process of C-S-H. This has resulted in increasing hydration degree of C3S and compressive strength. The second system studied was biphasic clinker C3S/C3A ground with hemi-hydrate and gypsum. An optimum sulfate has been observed, which move out with time to high rate of sulfate. The optimum sulfate was observed when the hydration of C3S, during the accelerated period, takes place simultaneously or slightly before the exothermic peak due to the high dissolution of C3A and precipitation of AFm. We showed the presence of AFm during the accelerated hydration of C3S, is the cause of the microstructure modification in the cement paste: the porosity increases with calcium sulfate addition but the hydrate assembly is more dense.

Cette thèse se compose de quatre essais théoriques, portant sur le capital humain et la croissance. L'objectif est de proposer de nouvelles approches afin de mieux identifier l'impact des politiques éducatives. Plus précisément, dans les chapitres un à trois, nos analyses sont menées dans un cadre à deux secteurs, dans la mesure où les différents secteurs qui composent une économie ne sont pas influencés de la même façon par l'éducation. Dans le quatrième chapitre nous nous intéressons aux enjeux politiques liés à la gestion des problèmes environnementaux en considérant le lien entre éducation et environnement. / This dissertation consists of four essays on human capital and growth. It aims at proposing approaches to better understand the influence of education policy. Specifically, we take into account sectoral properties, since education does not affect each sector in the same way. We also deal with the link between education and the environment, to address environmental challenges that are one of the major political issues.

This thesis contributes to the state of the art in integrated design of insect-scale piezoelectric actuated flapping wing vehicles through the development of novel theoretical models for flapping wing aerodynamics and piezoelectric actuator dynamics, and integration of these models into a closed form design process. A comprehensive literature review of available engineered designs of miniature rotary and flapping wing vehicles is provided. A novel taxonomy based on wing and actuator kinematics is proposed as an effective means of classifying the large variation of vehicle configurations currently under development. The most successful insect-scale vehicles developed to date have used piezoelectric actuation, system resonance for motion amplification, and passive wing pitching. A novel analytical treatment is proposed to quantify induced power losses in normal hover that accounts for the effects of non uniform downwash, wake periodicity and effective flapping disc area. Two different quasi-steady aerodynamic modelling approaches are undertaken, one based on blade element analysis and one based on lifting line theory. Both approaches are explicitly linked to the underlying flow physics and, unlike a number of competing approaches, do not require empirical data. Models have been successfully validated against experimental and numerical data from the literature. These models have allowed improved insight into the role of the wing leading-edge vortex in lift augmentation and quantification of the comparative contributions of induced and profile drag for insect-like wings in hover. Theoretical aerodynamic analysis has been used to identify a theoretical solution for the optimum planform for a flapping wing in terms of chord and twist as a function of span. It is shown that an untwisted elliptical planform minimises profile power, whereas a more highly tapered design such as that found on a hummingbird minimises induced power. Aero-optimum wing kinematics for hovering are also assessed. It is shown that for efficient flight the flapping velocity should be constant whereas for maximum effectiveness the flapping velocity should be sinusoidal. For both cases, the wing pitching at stroke reversal should be as rapid as possible. A dynamic electromechanical model of piezoelectric bending actuators has been developed and validated against data obtained from experiments undertaken as part of this thesis. An expression for the electromechanical coupling factor (EMCF) is extracted from the analytical model and is used to understand the influence of actuator design variables on actuator performance. It is found that the variation in EMCF with design variables is similar for both static and dynamic operation, however for light damping the dynamic EMCF will typically be an order of magnitude greater than for static operation. Theoretical contributions to aerodynamic and electromechanical modelling are integrated into a low order design method for propulsion system sizing. The method is unique in that aside from mass fraction estimation, the underlying models are fully physics based. The transparency of the design method provides the designer with clear insight into effects of changing core design variables such as the maximum flapping amplitude, wing mass, transmission ratio, piezoelectric characteristics on the overall design solution. Whilst the wing mass is only around 10% of the actuator mass, the effective wing mass is 16 times the effective actuator mass for a typical transmission ratio of 10 and hence the wing mass dominates the inertial contribution to the system dynamics. For optimum aerodynamic effectiveness and efficiency it is important to achieve high flapping amplitudes, however this is typically limited by the maximum allowable field strength of the piezoelectric material used in the actuator.

The optimum ordering strategies for the coded V-BLAST system with capacity achieving temporal codes on each stream are studied in this thesis. Mathematical representations of the optimum detection ordering strategies for the coded V-BLAST under instantaneous rate allocation (IRA), uniform power/rate allocation (URA), instantaneous power allocation(IPA) and instantaneous power/rate allocation (IPRA) are derived. For two transmit antennas, it is shown that the optimum detection strategies are based on the per-stream before-processing channel gains. Based on approximations of the per-stream capacity equation, closed-form expressions of the optimal ordering strategy under the IRA at low and high signal to noise ratio (SNR) are derived. Necessary optimality conditions under the IRA are given. Thresholds for the low, intermediate and high SNR regimes in the 2-Tx-antenna system under the IPRA are determined, and the SNR gain of the ordering is studied for each regime. Performances of simple suboptimal ordering strategies are analysed, some of which perform very close to the optimum one.

Automotive engines are becoming increasingly technically complex and associated legal emissions standards more restrictive, making the task of identifying optimum actuator settings to use significantly more difficult. Given these challenges, this research aims to develop a process for engine calibration optimisation by exploiting advanced mathematical methods. Validation of this work is based upon a case study describing a steady-state Diesel engine calibration problem. The calibration optimisation problem seeks an optimal combination of actuator settings that minimises fuel consumption, while simultaneously meeting or exceeding the legal emissions constraints over a specified drive cycle. As another engineering target, the engine control maps are required as smooth as possible. The Multidisciplinary Design Optimisation (MDO) Frameworks have been studied to develop the optimisation process for the steady state Diesel engine calibration optimisation problem. Two MDO strategies are proposed for formulating and addressing this optimisation problem, which are All At Once (AAO), Collaborative Optimisation. An innovative MDO formulation has been developed based on the Collaborative Optimisation application for Diesel engine calibration. Form the MDO implementations, the fuel consumption have been significantly improved, while keep the emission at same level compare with the bench mark solution provided by sponsoring company. More importantly, this research has shown the ability of MDO methodologies that manage and organize the Diesel engine calibration optimisation problem more effectively.

This paper estimates the determinants of exchange rate variability for 21 developed economies in 1980-1998. The results show that traditional criteria implied by the optimum currency area (OCA) theory, such as business cycle synchronisation, trade linkages and economy size, determine to a large extent bilateral exchange rate variability. Using the ordinary least squares estimation, we compute OCA indices for European economies vis-à-vis Germany and identify countries showing consistently large or little signs of convergence. We find that since 1998, most European developed economies have converged to Germany whether or not they are using the euro, suggesting that structural similarity is not driven solely by monetary integration. Our results from the model estimated by the generalized method of moments suggest that two additional criteria reflecting labour market flexibility and private credit growth are significant in explaining the exchange rate variability and lead to a ranking of countries different from the traditional approach. We find a positive relationship between the OCA indices and GDP decline during the economic crisis of 2008-09, which further supports the view that the OCA index is a useful indicator of the candidates' readiness to join the Euro Area. We apply the results to the...

Many regions of the world would like to replicate the financial and monetary integration of the European Monetary Union (EMU). Member countries of the Association of Southeast Asian Nations (ASEAN) have shown an interest in such an arrangement. ASEAN is a political, cultural, and economic association that includes Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam. Many of these nations are experiencing rapid economic development while others are still relatively poor and under developed. As such, they appear to be an unlikely group for currency unification. Older studies suggest that multiple currency union groupings may be possible in the short run that could be unified into a whole at an unspecified time in the future. The issue has been studied for some time and appeared defunct with the onset of the Asian Financial Crisis. More than a decade has passed and another more global financial crisis has ensued leaving many Asian countries in better shape than their highly developed trading partners in the west. This leads to the need for further examination of the possible unification of some or all ASEAN members into a Regional Currency Arrangement. This dissertation evaluates the readiness of the ASEAN nations for monetary union using data from the post Asian Financial Crisis period. Results of a formal G-PPP test show the area is an optimum currency area. Analysis of other criteria shows incredible diversity across the countries in the region that would make unification a challenge. Coordination of monetary policy would be most difficult given the variety of inflation rates and differences in depth of financial system development as explored in chapter 2. Trade has increased in the region leading to better linkages among economies but the data shows that reaching full integration of all countries by the 2020 deadline without disruptions in some economies may still be difficult.

Utmaningar i modern processortillverkning begränsar klockfrekvensen för enkeltrådiga applikationer, vilket har resulterat i utvecklingen av flerkärniga processorer. Dessa processorer tillåter flertrådig exekvering och ökar därmed prestandan. För att undersöka möjligheterna med parallell exekvering används en Fast Fourier Transform algoritm där trådprestanda mäts för olika skapade tester med varierande problemstorlekar. Dessa tester körs på tre testsystem och använder olika sökalgoritmer för att dynamiskt justera antalet trådar vid exekvering. Denna prestanda jämförs sedan med den högsta möjliga prestanda som kan fås genom Brute-Forcing. Testerna använder OpenMP-instruktioner för att specificera antalet trådar som finns tillgängliga för programexekvering. För mindre problemstorlekar resulterar färre antal trådar i högre prestanda. Motsatsen gäller för större problemstorlekar, där många trådar föredras istället. Denna rapport visar att användning av alla tillgängliga trådar för ett system inte är optimalt i alla lägen då det finns en tydlig koppling mellan problemstorlek och det optimala antalet trådar för maximal prestanda. Detta gäller för alla tre testsystem som omfattas av rapporten. Metodiken som har använts för att skapa testerna har gjort det möjligt att dynamiskt kunna justera antalet trådar vid exekvering. Rapporten visar också att dynamisk justering av antalet trådar inte passar för alla typer av applikationer. / As physical limitations limit the clock frequencies available for a single thread, processor vendors increasingly build multi-core systems with support for dividing processes across multiple threads for increased overall processing power. To examine parallelization capabilities, a fast fourier transform algorithm is used to benchmark parallel execution and compare brute-forced optimum with results from various search algorithms and scenarios across three different testbed systems. These algorithms use OpenMP instructions to directly specify number of threads available for program execution. For smaller problem sizes the tests heavily favour fewer threads, whereas the larger problems favour the native 'maximum' thread count. Several algorithms were used to compare ways of searching for the optimum thread values at runtime. We showed that running at maximum threads is not always the most optimum choice as there is a clear relationship between the problem size and the optimal thread-count in the experimental setup across all three machines. The methods used also made it possible to identify a way to dynamically adjust the thread-count during runtime of the benchmark, however it is not certain all applications would be suitable for this type of dynamic thread assignment

A avicultura brasileira assumiu nos últimos anos importante papel dentro do PIB nacional, e a produção de ovos dentro do setor vem tomando cada vez maior importância. No decorrer dos últimos anos vários avanços foram observados no que se refere ao melhoramento genético de poedeiras comerciais, no sentido de maiores produtividade e longevidade. Ambos parâmetros podem ser afetados pela atuação de radicais livres e nutrição adequada. Embora o organismo vivo apresente mecanismos fisiológicos que visam diminuir os danos causados por radicais livres, a suplementação destes pode promover benefícios, desde a reprodução da ave até o desempenho produtivo de poedeiras oriundas de matrizes suplementadas com substâncias antioxidantes, dentre elas a cantaxantina. Recentemente vários estudos têm sido feitos para a nutrição adequada das aves com utilização adequada de aminoácidos, energia, fontes minerais, enzimas, etc., para que atinjam o máximo potencial produtivo. Porém, os níveis vitamínicos têm sido pouco estudados, e normalmente com foco em frangos de corte e/ou níveis mínimos a serem trabalhados para que o animal não entre em deficiência, trabalhos com níveis vitamínicos visando produtividade máxima em poedeiras comerciais não foram encontrados na literatura pesquisada. O presente estudo teve como objetivo avaliar poedeiras comerciais modernas, da linhagem Hisex Brown, em duas situações: origem de matrizes suplementadas com cantaxantina e 25 hidroxicolecalciferol, e níveis vitamínicos altos contra níveis vitamínicos praticados comercialmente. O experimento foi inteiramente casualizado e ocorreu nas dependências da granja experimental da USP de Pirassununga. As aves foram alojadas com 1 dia de idade e mantidas até as 70 semanas, passando pelas fases de cria, recria e produção, em que tiveram os parâmetros zootécnicos observados e comparados. Como resultados, observou-se no trabalho quanto à suplementação das matrizes: melhor peso corporal aos 35 dias, e daí até o final da recria (p<0,05), não apresentando maiores consumos de ração em relação ao grupo controle. Na fase de produção observou-se melhor peso dos ovos e espessura da casca para o grupo tratado e maior resistência da casca para o grupo controle (p<0,05). Quanto aos níveis vitamínicos observou-se: vantagem em peso aos 35 dias, o que não se observou às 17 semanas, e observou-se menor conversão alimentar no grupo controle. Durante a fase de produção, o grupo tratado apresentou resultados melhores em peso de ovos e resistência da casca (p<0,05) / Brazilian poultry has been taken an important part on brazilian economy on the past few years, and the egg production has been taken an important part on brazilian poultry. During the last years, several improvements has been done on the way of better production and longer lifetime of the layers. Both parameters are influenced by free radicals action and the correct use of nutrition. Although life animals have system to avoid damages caused by free radicals, suplementation with antioxidants can bring them benefits, since the reproduction of the breeder, until the production of the layer provided from light breeders suplemented, one of these substances is cantaxantin. Recently, studies have been conduced to determine the appropriate levels of aminoacids, energy, minerals, enzymes, etc., everything to permit the animal, the maximum production. However, vitamin levels haven´t been studied that much, and normally, the goal of theses studies are broilers and/or the minimum necessary to don´t let animals be deficient. This study had the goal to evaluate layers of Hisex Brown lineage, on two situations: the suplementation of the light breeder with cantaxantin and 25 hidroxicolecalciferol, and optimum vitamin nutrition against the ones comercially used. The experiment was entirely randomized designed, and occurred on the experimental houses of USP of Pirrasununga. The day old pullet were housed and maintained there for 70th weeks old, going throw rearing and production period, on which had its parameteres evaluated. As the results, on the work with breeders suplementation better body weight at 35 days old, and than until the end of rearing period (p<0,05), without higher feed consumption then control group. On the production period it was observed higher egg weight and thickness of the shell (p<0,05) for the suplemented breeder group, but better shell resistance for the control group. For the work wtih optimum vitamin nutrition results it was observed improvement of body weight at 35 days old (p<0,05) on the OVN group, but it was not observed until the end of rearing period. During the production time it was not observed any improvement but the weight and resistance of eggs on OVN group (p<0,05)

Este trabalho apresenta uma metodologia de alocação de dispositivos de proteção e manobra ao longo de alimentadores primários de um sistema de distribuição de energia elétrica, de forma a otimizar a quantidade de consumidores afetados e da energia média não distribuída, na ocorrência de desligamentos provocados por uma falha. Na alocação dos dispositivos, utiliza-se um algoritmo matemático que considera vários parâmetros envolvidos no fenômeno, que explicam o mérito de cada alternativa possível, ponderando as variações de benefício. Além de indicar os locais adequados para instalação dos dispositivos de proteção e manobra, a metodologia proposta permite a elaboração de regras para auxiliar a priorização de ações de manutenção e para otimizar os investimentos em alimentadores. Outro resultado da pesquisa é a relocação de dispositivos de proteção e manobra existentes em alimentadores, considerando o seu reposicionamento para melhorar o desempenho em face de faltas que provocam interrupções e portanto diminuindo os indicadores FEC frequência média de interrupção de fornecimento e a END pela energia média não distribuída.Com o objetivo de comprovar a eficácia da metodologia proposta, desenvolveu-se uma ferramenta para sua operacionalização e posterior aplicação com sucesso, em um Estudo de Caso real de uma Concessionária brasileira. / This paper presents a methodology for allocation of protection and switching devices along primary feeders of a system for electricity distribution in order to optimize both the number of affected consumers and the average amount of energy that is not supplied, in case of interruptions caused by a failure. For the allocation of the devices it is used a mathematical algorithm that considers various parameters involved in the phenomenon, explaining the relevance of each possible alternative and pondering benefit variations. Besides indicating the adequate places to install the protection and switching devices, the proposed methodology allows elaborating roles that help taking prior actions to maintain and optimize the investments in feeders. Other aspect of the research is the relocation of protection and switching devices that exist in the feeders, considering their replacing in order to enhance the performance in the occurrence of failures that cause interruptions and so, reducing the FEC indicators supplying interruption medium frequency and the END (Energy not supplied). Aiming to prove the effectiveness of the proposed methodology, it was developed a tool for its operation and subsequent successful application in a study case, that represents a real situation of a Brazilian electrical power retailer company.