CCA-adding enzymes synthesize and maintain the C-C-A sequence at the tRNA 3'-end, generating the attachment site for amino acids. While tRNAs are the most prominent substrates for this polymerase, CCA additions on non-tRNA transcripts are described as well. To identify general features for substrate requirement, a pool of randomized transcripts was incubated with the human CCA-adding enzyme. Most of the RNAs accepted for CCA addition carry an acceptor stem-like terminal structure, consistent with tRNA as the main substrate group for this enzyme. While these RNAs show no sequence conservation, the position upstream of the CCA end was in most cases represented by an adenosine residue. In tRNA, this position is described as discriminator base, an important identity element for correct aminoacylation. Mutational analysis of the impact of the discriminator identity on CCA addition revealed that purine bases (with a preference for adenosine) are strongly favoured over pyrimidines. Furthermore, depending on the tRNA context, a cytosine discriminator can cause a dramatic number of misincorporations during CCA addition. The data correlate with a high frequency of adenosine residues at the discriminator position observed in vivo. Originally identified as a prominent identity element for aminoacylation, this position represents a likewise important element for efficient and accurate CCA addition.

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Scania is a Swedish automotive manufacturer for heavy vehicles and engines. It also offers transport solutions and long term commitment for customers. In today's Scania, a modular system provides a huge variety of specifications to meet varying dramatic needs for different customers. In order to be able to meet the diverse requirements of customers, modular approach with the support of reusable components is used to increase the efficiency of designing different products. To customize both product development and product design, computer aided design(CAD) is used to support the process of design and design documentation. "CATIA" is a multi-platform CAD software and "ENOVIA" is a product modeling product offers product database management for virtual model design into CATIA, both "CATIA" and "ENOVIA" are developed by the French company Dassault Systemes are chosen by Scania to support its product development. The modular system approach requires the system support for product structure, which is managed by a mainframe called SPECTRA. The thesis project is mainly about system designing a new module which takes the responsibility for exchanging information between SPECTRA and ENOVIA. In more detail, the new component is to perform a mapping of data in SPECTRA format into a format which ENOVIA can import. The mapping module has several interfaces with other applications in the system. JavaMigrator provides the environment to import data from the mainframe and transfer the data into the module and finally output the expected data format into ENOVIA. To achieve this purpose, several possible solutions were proposed and several methods were tried. Since an in-house developed CAA-module is highly preferred by Scania, the new mapping component will finally be designed into two separate modules, the first part converts the XML extracted from SPECTRA into an intermediate format and the second part is designed to convert the intermediate file into the expected target file. The intermediate file is required, since the format is independent of changes in both SPECTRA and ENOVIA. Furthermore, it is flexible and less complex to maintain than direct mapping from exported XML to ENOVIA. The report focuses on five parts, background, project specification, methodology, implementation, result and future work.

Regulation in its generic sense has existed for a very long time in different forms, with different aims and different problems of accountability, but the study of competition regulation by a Government agency has perhaps become fashionable only in recent years. This thesis consists of two leading themes. First, it will contend that, whilst the market system has been seriously underestimated as a social institution to the extent that it should be left to operate and organise itself where that is possible, it is at the same time not always self-regulating. Residual intervention by the State or its agencies will remain necessary in strategic cases, either to protect individual autonomy and choice, or to correct failures of the market system. The question is simply more or less regulation. Secondly, and on that premise, competition regulation must be distinguished into economic regulation and antitrust regulation because the relationship between them is inversely proportional: the more intense economic regulation is, the less important antitrust regulation becomes. By implication then, economic liberalisation or deregulation must be accompanied by a robust framework of antitrust regulation to ensure that the conditions of sustainable competition are not threatened by anti-competitive practices. Conditions of sustainable competition are thus critical for market contestability. For many years, domestic and international airline competition has been the subject of comprehensive regulation. With the passage of time, however, the thinking has changed and, no doubt, liberal policies and practices will continue to find expression in future political and economic sentiments. The responsibility for regulating airlines in the United Kingdom falls on the Civil Aviation Authority, which has played a formidable role in transforming the policy of heavy regulation into minimal regulation, although much of that regulatory landscape has now been altered with the advent of the Single European Aviation Market. The experiences of, both, the CAA and the new SEATNI provide an illuminating account of the evolutionary process of regulating airline competition, that from economic to antitrust regulation.

Made available in DSpace on 2018-08-01T23:58:47Z (GMT). No. of bitstreams: 1 tese_10450_DISSERTAÇÃO FELIPE ZANELLATO COELHO COMPLETA PDF.pdf: 5435895 bytes, checksum: 0407e27924b1cfbdf97715466ba0e4d6 (MD5) Previous issue date: 2016-09-05 / A incorporação de resíduos e subprodutos industriais nos traços de concreto é uma solução para minimizar os impactos causados pelos processos produtivos dos materiais que o compõem. Vários estudos avaliam o desempenho técnico da incorporação de resíduos e subprodutos industriais nos traços de concreto, porém para decidir qual mistura apresenta a menor carga ambiental é necessário fazer uma análise completa de todo seu ciclo de vida. A avaliação do ciclo de vida (ACV) é uma metodologia para avaliar os potenciais impactos ambientais e os recursos utilizados ao longo do ciclo de vida de um produto. Portanto, o objetivo desta dissertação consiste no desenvolvimento de uma ACV comparativa para analisar 162 traços de Concretos Autoadensáveis (CAA) com altas proporções de incorporação de resíduos e subprodutos industriais em um cenário na cidade de Berkeley, Califórnia-EUA. A pesquisa aponta quantitativamente quais os traços que apresentam o melhor desempenho ambiental no cenário proposto. Os traços foram extraídos de 15 artigos científicos que comprovaram a viabilidade técnica dos concretos analisados. Os CAA's estão sendo cada vez mais utilizados para a construção de elementos de concreto complexos altamente reforçados e para estruturas de concreto maciço, como barragens e fundação que necessitam de misturas com maior fluidez. Para avaliar o desempenho ambiental dos CAA's os traços foram separados em 3 classes de resistência e analisados com o Software SIMAPRO, método de avaliação de impacto IMPACT 2002+, banco de dados ECOINVENT e unidade funcional de 1 m3. A ACV realizada desconsiderando as fases de pós-fabricação, ou seja, o limite do sistema é "cradle-to-gate". Os resultados mostram que as categorias de danos mais afetadas foram a Saúde Humana, Mudanças climáticas e os Recursos Energéticos por consequência das altas emissões de partículas respiratórias inorgânicas, emissão de GEE's e o consumo de energia não renovável respectivamente. O traço de menor impacto por categoria apresenta índices de emissões de partículas respiratórias inorgânicas, emissão de GEE's e o consumo de energia não renovável menor que o traço de maior impacto nas proporções de 57%, 65%, 55% respectivamente na classe 1A, 55%, 78%, 55% respectivamente na classe 1B e 49%, 78%, 51% respectivamente na classe 2. Em resumo, os ecoconcretos apresentam ganhos ambientais significativos que podem ajudar a minimizar o aquecimento global, reduzir o esgotamento dos recursos naturais e promover a construção verde.

The noise generated by jet engines represents a significant environmental concern that still needs to be addressed. Accurate and efficient numerical predictions are a key step towards reducing jet noise. The current standard in highidelity prediction of jet noise is large eddy simulation (LES), which resolves the large turbulent scales responsible for the low and medium frequency noise and models the smallest turbulent scales that correspond to the high frequency noise. While LES requires significant computational resources to produce an accurate solution, it fails to resolve the noise in the high frequency range, which cannot be simply ignored. To circumvent this, in this dissertation the Coupled LES-Synthetic Turbulent method (CLST) was developed to model the missing frequencies that relate to un-resolved sub-grid scale fluctuations in the flow. The CLST method combines the resolved, large-scale turbulent fluctuations from very large eddy simulations (VLES) with modeled, small-scale fluctuations from a synthetic turbulence model. The noise field is predicted using a formulation of the linearized Euler equations (LEE), where the acoustic waves are generated by source terms from the combined fluctuations of the VLES and the synthetic fields. This research investigates both a Fourier mode-based stochastic turbulence model and a synthetic eddy-based turbulence model in the CLST framework. The Fourier mode-based method is computationally less expensive than the synthetic eddy method but does not account for sweeping. Sweeping and straining of the synthetic fluctuations by large flow scales from VLES are accounted for in the synthetic eddy method. The two models are tested on a Mach 0.9 jet at a moderately-high Reynolds number and at a low Reynolds number. The CLST method is an efficient and viable alternative to high resolution LES or DNS because it can resolve the high frequency range in the acoustic noise spectrum at a reasonable expense.

Le bruit généré par l'impact du sillage de la soufflante avec les aubes du redresseur est une source prédominante des turboréacteurs en conditions d'approche, et la composante à large bande contribue fortement au niveau sonore global. Une méthode numérique basée sur un code CAA résolvant les équations d Euler est développée dans cette thèse afin d'estimer le bruit d'interaction entre un sillage turbulent et un aubage de géométrie quelconque. Le sillage amont est modélisé à l'aide d'une méthode stochastique supposant un spectre de turbulence homogène isotrope et une représentation spatiale simplifiée du champ de vitesse. Ces fluctuations de vitesse sont injectées dans le code CAA via des conditions aux limites adéquates. La méthode ainsi mise en place est validée dans un premier temps sur des cas d'interaction avec une plaque plane en comparant les résultats numériques aux solutions du modèle d'Amiet. Un chaınage avec une méthode intégrale est aussi réalisé pour estimer le rayonnement acoustique. La méthode numérique est ensuite mise en œuvre pour simuler la réponse acoustique d'un profil isolé avec un bord d'attaque ondulé conçu et testé dans la soufflerie de l'ISVR dans le cadre du projet européen FLOCON. Enfin, la méthodologie est étendue à des configurations de grilles d'aubes annulaires en conduit. Après une étape de validation sur des cas monofréquentiels issus d'un benchmark CAA, des simulations large bande sont réalisées, tout d'abord sur une configuration de grille d'aubes sans incidence (écoulement axial uniforme) testée en soufflerie au LMFA, puis sur une configuration plus complexe de grille d'aubes non chargée en écoulement tournant proposée par Atassi / Noise generation due to the rotor wakes impinging the stator vanes is a dominant turbofan source at approach conditions, and the broadband noise component is significantly contributing to the overall level. A numerical method based on a CAA code solving the Euler equations is developped in this thesis in order to simulate the interaction noise between a turbulent wake and a vane row without geometry restrictions. The upstream turbulent flow is synthesized using a stochastic approach by considering an homogeneous isotropic turbulence spectrum model and a simplified spatial representation of the velocity field. These velocity gusts are injected in the CAA code by implementing a suited boundary condition. The present methodology is first va- lidated against turbulence-flat plate interaction cases, by comparing the numerical predictions to Amiet model solutions. A chaining with an integral formulation is also performed to assess the acoustic far-field. Then, the method is used to estimate the acoustic response of an isolated airfoil with a wavy leading egde, designed and tested in ISVR wind tunnel in the framework of European FLOCON project. Finally, the computations are extended to ducted annular grid configurations. After a validation step on single-frequency cases described in a CAA benchmark, broadband noise simulations are performed, firstly on a flat-plate annular grid in a uniform axial flow tested in the LMFA wind tunnel, and then on a more complex configuration related to an unloaded grid in a swirling mean flow proposed by Atassi

Le présent travail a consisté à évaluer, améliorer et valider plus avant une méthode de couplage faible CFD/CAA, notamment relativement à son application à des problèmes réalistes de bruit avion. Entre autres choses, il a été ici montré dans quelle mesure une telle méthode hybride peut effectivement (i) s’accommoder des contraintes inhérentes aux applications réalistes, (ii) sans être menacée par certains de ses inévitables effets de bord (tels que la dégradation du signal auxquelles sont soumises les données CFD, lorsqu’elles sont traitées ou exploitées acoustiquement). / The present work consisted in improving, assessing and validating further the CFD/CAA surface weak coupling methodology, with respect to its application to realistic problems of aircraft noise. In particular, it was here shown how far such hybrid methodology could (i) cope with all stringent constraints that are dictated by real-life applications, (ii) without being jeopardized by some of the unavoidable side-effects (such as the signal degradation to which CFD data are subjected, when processed or being then acoustically exploited).

CCA-adding enzymes synthesize and maintain the C-C-A sequence at the tRNA 3''-end, generating the attachment site for amino acids. While tRNAs are the most prominent substrates for this polymerase, CCA additions on non-tRNA transcripts are described as well. To identify general features for substrate requirement, a pool of randomized transcripts was incubated with the human CCA-adding enzyme. Most of the RNAs accepted for CCA addition carry an acceptor stem-like terminal structure, consistent with tRNA as the main substrate group for this enzyme. While these RNAs show no sequence conservation, the position upstream of the CCA end was in most cases represented by an adenosine residue. In tRNA, this position is described as discriminator base, an important identity element for correct aminoacylation. Mutational analysis of the impact of the discriminator identity on CCA addition revealed that purine bases (with a preference for adenosine) are strongly favoured over pyrimidines. Furthermore, depending on the tRNA context, a cytosine discriminator can cause a dramatic number of misincorporations during CCA addition. The data correlate with a high frequency of adenosine residues at the discriminator position observed in vivo. Originally identified as a prominent identity element for aminoacylation, this position represents a likewise important element for efficient and accurate CCA addition.

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents a progress report on Global Air Traffic Management (GATM) avionic system test activities at the Air Force Flight Test Center. In many parts of the world today the continuing growth of commercial air traffic is running up against limits brought on by overuse of aviation resources. Air corridors in Europe and on transoceanic air routes are operating at maximum capacity. Civil Aviation Authorities (CAAs) are working these challenges on two levels—near-term incremental improvements and long-term visionary changes. Each country has a CAA; ours being the Federal Aviation Administration (FAA). Near-term solutions focus on better utilization of resources such as air space and frequency spectrum and improved performance of air traffic control facilities. Long-term visionary changes, such as free flight, could fundamentally change the current civil aviation business process model. CAA policies and standards are driving near-term improvements and migration toward long-term objectives. This initiative is referred as Communication Navigation Surveillance/Air Traffic Management (CNS/ATM). Implementation of the U.S. military’s vision, Global Reach/Global Power, requires the ability to rapidly deploy armed forces to major regional conflicts anywhere in the world, and to sustain these forces for as long as it takes to resolve these conflicts. To achieve this goal and accomplish rapid deployments while at the same time minimizing costs, the Air Force has adopted a solution that makes extensive use of CNS/ATM. The Air Force calls its initiative Global Air Traffic Management (GATM). Air Force aircraft equipped with GATM avionics will be able to use CNS/ATM capabilities such as reduced vertical separation minimum (RVSM), 8.33 kHz data links, automatic dependent surveillance - broadcast (ADS-B), and global communication networks. These capabilities make possible improved flight safety, lower fuel costs, and quicker turn times. The Air Force Flight Test Center supports the GATM initiative by providing Air Traffic Control (ATC) Communications Test Facilities and Avionic System Test (ACTFAST) capabilities to support aircraft modification programs.