In 2018, the shipping industry accounted for 2.89% of worldwide greenhouse gas (GHG) emissions, with carbon dioxide (CO2) being the most significant GHG affecting global warming (IMO, 2020). This research aims to introduce a method for selecting propellers at the early design stage to lower CO2 emissions from ships.Traditionally, propeller design assumes that a ship travels in a straight line at a constant speed. However, real-sea conditions involve environmental forces and ship maneuvering, requiring frequent adjustments in speed and direction. These adjustments affect the flow angle and velocity at the propeller, causing it to operate outside its design point and, as a result, reducing its efficiency.To tackle this issue, a MATLAB-based simulation program was developed. Which predicts ship maneuvering motions in 4 degrees of freedom (DOF)—surge, sway, yaw, and roll—using the MMG model. The program applies wave and wind forces, calculates ship motion responses in each iteration, and employs two controllers to manage the rudder and propeller speed, ensuring the ship stays on course and arrives on time.The optimization process is iterative, using simulation outcomes to determine propeller speed, thrust, drift angle, etc., and then selecting an optimized propeller with the program's optimization tool that is more adequate for the operational condition.Building on Trodden's (2014) work, this approach improves maneuvering simulations' accuracy by incorporating ship rolling motion, more realistic wave modeling, and more accurate hydrodynamic coefficients. This offers a closer representation of operational conditions.Case studies comparing this method with the traditional approach to propeller selection have shown the simulation program's precision and its effectiveness in improving propeller open water efficiency by 1.65% and reducing CO2 emissions by 1.47% for a Pure Car Carrier (PCC) ship. The results of the research showed a promising potential for the program to predict ship maneuvering motions in real-sea conditions and optimize the propeller. / År 2018 stod sjöfartsindustrin för 2,89 % av de globala utsläppen av växthusgaser (GHG), där koldioxid (CO2) är den mest betydande växthusgasen som påverkar den globala uppvärmningen (IMO, 2020). Denna forskning syftar till att introducera en metod för val av propellrar i det tidiga designskedet för att sänka CO2-utsläppen från fartyg.Traditionellt antar propellerdesignen att ett fartyg reser i rakt linje med konstant hastighet. Men verkliga sjöförhållanden involverar miljöpåverkan och fartygsmanövreringar, vilket kräver frekventa justeringar av hastighet och riktning. Dessa justeringar påverkar flödesvinkeln och hastigheten vid propellern, vilket gör att den opererar utanför sin designpunkt och som ett resultat minskar dess effektivitet. För att ta itu med denna fråga utvecklades ett MATLAB-baserat simuleringsprogram. Programmet förutsäger fartygsmanövreringsrörelser i 4 frihetsgrader (DOF) - surge, sway, yaw och roll - med användning av MMG-modellen. Programmet tillämpar våg- och vindkrafter, beräknar fartygsrörelsesvar i varje iteration och använder två kontrollanter för att hantera rodret och propellerhastigheten, vilket säkerställer att fartyget håller kursen och ankommer i tid.Optimeringsprocessen är iterativ, använder simuleringsresultat för att bestämma propellerhastighet, dragkraft, drifvinkel osv., och väljer sedan en optimerad propeller med programmets optimeringsverktyg som är mer lämplig för driftsförhållandet. Genom att bygga vidare på Troddens (2014) arbete förbättrar denna metod noggrannheten i manövreringssimuleringar genom att inkludera fartygets rullningsrörelse, mer realistisk vågmodellering och mer exakta hydrodynamiska koefficienter. Detta erbjuder en närmare representation av driftsförhållanden.Fallstudier som jämför denna metod med det traditionella tillvägagångssättet för val av propeller har visat simuleringsprogrammets precision och dess effektivitet i att förbättra propellerns öppenvatteneffektivitet med 1,65 % och minska CO2-utsläppen med 1,47 % för ett Pure Car Carrier (PCC) -fartyg. Forskningens resultat visade en lovande potential för programmet att förutsäga fartygsmanövreringsrörelser under verkliga sjöförhållanden och optimera propellern.

[pt] A busca por maior eficiência, sistemas confiáveis e redução da pegada de carbono é uma tendência na indústria de Petróleo e Gás (OeG). A Completação Inteligente de Poços (IWC) tornou-se amplamente adotada, e a Válvula de Controlede Influxo/Intervalo (ICV) desempenha um papel significativo no controle da vazão de produção e injeção. A eletrificação dos ativos de OeG, incluindo as ferramentas de IWC, oferece um benefício duplo de aumento dos fatores de recuperação e alinhamento com os esforços globais de descarbonização. Para desenvolver uma ICV Elétrica, é necessário projetar um atuador eletromecânico capaz de operar sob condições desafiadoras e limitações de energia elétrica. Esta dissertação apresenta o projeto e os testes de um atuador eletromecânico em um protótipo de ICV Elétrica em escala real. O desempenho do atuador foi avaliado por meio de uma combinação de modelagem matemática e testes empíricos sob várias condições operacionais, incluindo alta e baixa temperaturas e pressões diferenciais. Os principais resultados desta pesquisa demonstraram que o modelo matemático apoiou efetivamente o design do atuador, com os resultados calculados alinhando-se com os testes funcionais em temperatura ambiente e pressão diferencial zero. / [en] The seek for higher efficiency, reliable systems, and carbon footprint reduction is a trend in the Oil and Gas (OandG) industry. Intelligent Well Completion (IWC) has become a widely adopted and the Inflow/Interval Control Valve (ICV) plays a significant role in controlling production and injection flow rates. Electrification of OandG assets, including the IWC tools, offers a dual benefit of increased recovery factors and alignment with global decarbonization efforts. To develop an Electric ICV, the design of an electromechanical actuator capable of operating under challenging conditions and electrical power limitations is required. This dissertation presents the design and testing of an electromechanical actuator in a full-scale prototype Electric ICV. The actuator s performance was assessed through a combination of mathematical modeling and empirical testing under various operational conditions, including high and low temperatures and differential pressures. Key findings from this research demonstrated that the mathematical model effectively supported the actuator s design, with calculated results aligning closely with functional tests at room temperature and zero differential pressure.

The effectiveness of South Africa's policy framework towards attracting FDI has been questionable. Determined to redress the instabilities created by the apartheid regime, the Government of National Unity (GNU) commissioned the Macroeconomic and Research Group (MERG), and charged it to devise appropriate policy reforms and intervention mechanism to address the shortcomings. This research critically interrogates the effectiveness of government's policy reforms towards attracting FDI, especially the impacts of the Reconstruction and Development Programme (RDP), the Growth, Employment and Redistribution (GEAR) initiative and the Accelerated and Shared Growth Initiative of South Africa (ASGISA). This research concludes that the policy determinants for inflow FDI have been self-defeating. Also, it was found that necessary reforms would have to be conducted to correct some of the shortcomings of the macroeconomic policies, as a way of creating an environment that is capable of attracting greenfield investments (FDI) to South Africa. / Business Management / M. Com. (Business Management)

Des bâtiments de grande hauteur sont construits avec un poids et un amortissement structurel de plus en plus faibles en lien avec l'évolution des techniques de construction et des matériaux. La connaissance des charges de vent dynamiques est un enjeu important pour la conception des grands bâtiments afin de garantir leur sécurité structurelle. L'objectif de cette thèse est d’évaluer la capacité de la simulation numérique des grandes échelles (LES) à prédire les charges de vent sur les structures et d’étudier l'influence des conditions d’entrée d’une simulation LES sur ces charges. Des expériences ont été menées à échelle réduite dans la soufflerie atmosphérique NSA du CSTB afin de documenter l’écoulement atmosphérique modélisé, de caractériser son interaction avec un bâtiment et les charges de vent statiques et dynamiques résultantes. Le sillage du bâtiment a été caractérisé grâce à des mesures PIV. Les efforts globaux et les pressions locales ont été mesurés par une balance et des prises de pression à haute fréquence. Ces expériences en soufflerie ont permis de développer un générateur de conditions amont (GCA) pour la simulation LES, visant à reproduire les principales caractéristiques de la turbulence dans la couche limite. La base de données constituée a également permis de qualifier les résultats des simulations LES réalisées avec le code OpenFOAM dans la configuration de l’expérience. L’utilisation du nouveau GCA et d’un générateur dégradé qui ne respecte pas toutes les caractéristiques de l'écoulement a permis de montrer la nécessité de bien reproduire les caractéristiques du vent incident pour accéder aux charges dynamiques sur le bâtiment. / High-rise buildings are built with increasingly low weight and structural damping in relation to the evolution of construction techniques and materials. The understanding of dynamic wind loads is an important issue for the design of high-rise buildings in order to guarantee their structural safety. The objective of the present work is to assess the ability of large eddy simulation (LES) to predict wind loads on structures and to investigate the influence of the inflow boundary conditions of a LES simulation on these loads. Experiments were carried out at a small scale in the NSA atmospheric wind tunnel of CSTB to document the modeled atmospheric boundary layer, to characterize its interaction with a building and the resulting static and dynamic wind loads. The wake flow around the building has been characterized by PIV measurements. Global and local wind loads were measured by a high frequency force balance and high frequency pressure taps. These wind tunnel experiments allowed for the development of an inflow turbulence generator for the LES simulation,which was aimed at reproducing the main characteristics of turbulence in the boundary layer. The database also made it possible to assess the quality of the results of the LES simulations carried out with the OpenFOAM code in the same configuration as the experiment. The use of both the new turbulence generator and a degraded one that does not account for all the characteristics of the flow has made it possible to show the necessity to reproduce the characteristics of the upstream wind flow in order to access the dynamic wind loads on the building.

A Constituição Federal de 1988 conferiu aos Municípios e ao Distrito Federal a competência para instituir o imposto sobre serviços de qualquer natureza definidos em lei complementar, com exceção dos serviços de transporte interestadual e intermunicipal e dos serviços de comunicação, que são tributados pelos Estados por meio do ICMS. Um dos pontos principais do exercício daquela competência está na delimitação da base de cálculo do ISS, por se tratar do elemento que indicará o montante da riqueza que o contribuinte obteve com a prestação do serviço e sobre o qual o ISS será calculado. É necessário, então, que a base de cálculo definida na lei municipal para a cobrança do ISS tenha estreita relação com o fato jurídico prestar serviço de qualquer natureza, pois é somente a riqueza decorrente dessa materialidade que poderá ser atingida pelo ISS. Sendo assim, caso um Município preveja, em lei própria, que os valores que não foram recebidos pelo prestador como remuneração pelo serviço executado em favor do tomador também devem compor a base de cálculo do ISS, a cobrança desse imposto que se baseie nessa lei será inconstitucional, pois atingirá valores que não revelam capacidade contributiva do prestador do serviço. Considerando-se que a Lei Complementar n.º 116/2003, ao exercer a função de lei complementar nacional prescritora de normas gerais em matéria de cobrança de ISS, estabelece que a sua base de cálculo deve ser o preço do serviço, torna-se necessário verificar quais são os limites semânticos que podem ser atribuídos a essa expressão para que o ISS não seja calculado sobre valores que não representem receita decorrente da prestação de serviço. Para tal análise, primeiramente serão apresentados os critérios que compõem a regra-matriz de incidência do ISS, de tal forma que seja possível demonstrar a relação intrínseca que cada um deles estabelece com a materialidade tributável por meio desse imposto. Relação essa que se destaca no estudo da base de cálculo como critério quantitativo daquela regra-matriz, posto que deve compreender apenas os valores recebidos pelo prestador como remuneração pelo serviço prestado. E para diferenciar esses valores daqueles que são recebidos pelo prestador do serviço do seu tomador como reembolso de despesas, serão propostos alguns critérios objetivos que devem ser aplicados na análise de cada uma das despesas envolvidas em uma prestação do serviço para que se determinem se os valores que serão empregados no seu custeio devem ou não compor a base de cálculo do ISS. Além disso, também serão propostos critérios para diferenciar os valores recebidos pelo prestador que são incorporados ao seu patrimônio daqueles que apenas transitam temporariamente por ele e identificar quais deles sofrerão a incidência do ISS. Por fim, será também analisada a necessidade de prescrição de critérios para o rateio do preço cobrado pela execução concomitante de uma prestação de serviço em estabelecimentos localizados em Municípios diferentes, de tal forma que todos esses Municípios possam definir uma base de cálculo constitucional para a apuração do ISS que cada um tem competência para cobrar sobre esse fato jurídico tributário. / The Federal Constitution of 1988 attributed to municipalities and the Federal District the competence to institute tax on services of any nature (ISS) as defined in a supplementary law, with exception to interstate and intermunicipal transportation services and services of communication, taxed by the States ICMS. One of the main points of municipalities competence refers to the assessment of the ISS tax base, by the designation of which value obtained by the taxpayer through the service rendered is subjected to taxation. The tax base defined by the municipal law to charge the ISS should be strictly related to the legal fact of providing service of any nature. Only the value obtained through this materiality is subjected to the ISS. In case a particular municipal legislation anticipates the addition to the ISS tax base of values received by the provider other than the compensation for the service rendered in favor of a client, the charging of the tax based on this law will be unconstitutional, since it deals with values over the taxpayers contributive capacity. While performing the function of prescribing national general norms related to ISS charging, Supplementary Law 116/2003 establishes that the tax base should be the price of service. It becomes necessary to verify the semantic limits that may be attributed to the expression price of service to avoid the calculation of ISS on values that do not represent the service compensation. For such analysis, this thesis presents, first, the criteria that form the rule array of ISS incidence, demonstrating the intrinsic relation of each one of the criterion with the taxable materiality. This relation stands out in the study of the tax base as a quantitative criterion of the rule array of ISS incidence, since it should encompass only the values received by the provider as compensation for the service rendered. To differentiate these values from those received by the service provider from the client as reimbursement of expenses, this thesis proposes objective criteria to analyze each expenditure involved in a service provision, in order to determine whether the values applied to its costing should form the ISS tax base. This thesis also proposes criteria to differentiate values received that are definitely incorporated to the providers patrimony from those that are temporary. These criteria also identify which of these values could be subjected to the ISS. Finally, this thesis analyses the prescription of criteria to the assessment of the price charged for service simultaneously provided at facilities located at different municipalities, making it possible for all these municipalities to define a constitutional tax base to assess the ISS each one has the competence to charge.

The effectiveness of South Africa's policy framework towards attracting FDI has been questionable. Determined to redress the instabilities created by the apartheid regime, the Government of National Unity (GNU) commissioned the Macroeconomic and Research Group (MERG), and charged it to devise appropriate policy reforms and intervention mechanism to address the shortcomings. This research critically interrogates the effectiveness of government's policy reforms towards attracting FDI, especially the impacts of the Reconstruction and Development Programme (RDP), the Growth, Employment and Redistribution (GEAR) initiative and the Accelerated and Shared Growth Initiative of South Africa (ASGISA). This research concludes that the policy determinants for inflow FDI have been self-defeating. Also, it was found that necessary reforms would have to be conducted to correct some of the shortcomings of the macroeconomic policies, as a way of creating an environment that is capable of attracting greenfield investments (FDI) to South Africa. / Business Management / M. Com. (Business Management)

Lors du développement d’un nouvel avion, l’estimation des échanges d’énergie entre l’air ambiant et les parois est une donnée cruciale pour la conception aérothermique. Cette conception repose de plus en plus sur des simulations numériques mais certains phénomènes d’aérothermique externe, comme le jet débouchant du système de dégivrage des nacelles moteur, montrent les limites des modèles RANS classiques. La simulation des grandes échelles (LES) se révèle bien adaptée à ce type de phénomène mais se heurte à un coût de calcul extrêmement élevé pour ces écoulements pariétaux à très grand nombre de Reynolds. Pour lever cette limitation, cette thèse propose l’étude de deux briques fondamentales : la LES avec loi de paroi (WMLES) conjuguée à l’injection d’une couche limite turbulente à l’entrée du domaine. Pour une meilleure compréhension et une utilisation fiable de l’approche loi de paroi, on se concentre tout d’abord sur les sources d’erreur qui lui sont associées. Après les avoir identifiées, on propose une correction de l’erreur de sous-maille ainsi qu’une loi de paroi adaptée aux écoulements compressibles. Grâce à ces deux éléments, on obtient une estimation correcte du flux de chaleur pariétal sur des simulations WMLES de canal plan supersonique sur parois froides. Puis, pour préparer la transition vers des applications plus industrielles, on introduit un schéma numérique plus dissipatif ce qui nous permet d’étudier l’influence de la méthode numérique sur l’approche loi de paroi. Dans une seconde partie dédiée à l’injection de couche limite pour la WMLES, on sélectionne une méthode basée sur l’injection de perturbations combinée à un terme de contrôle volumique. On montre que des simulations WMLES utilisant cette méthode d’injection permettent d’établir une couche limite turbulente réaliste à une courte distance en aval du plan d’entrée, à la fois sur une plaque plane mais également sur un écoulement de jet débouchant à la géométrie plus complexe, représentative d’un cas avion. / During the design of a new aircraft, the prediction of energy exchanged between the ambient air and the aircraft walls is crucial regarding aerothermal design. Numerical simulations plays a role of increasing importance in this design. However classical RANS models reach their limits on some external aerothermal flows, like the jet-in-cross-flow from the anti-icing system oh the engine nacelles. The large eddy simulation (LES) is well suited to this kind of flow but faces an extremely large computational cost for such high Reynolds number wall-bounded flows. To remove this limitation, we propose two building blocks: the Wall Modeled LES (WMLES) combined with a turbulent inflow generation. For a better understanding and a reliable use of the WMLES, we first focus on the sources of error related to this approach. We propose a correction to the subgrid-scale error as well as a wall model suitable for compressible and anisothermal flows. Thanks to these two elements, we correctly predict the wall heat flux in WMLES computations of a supersonic isothermal-wall channel flow. Then, to allow the computation of more industrial flows, we introduce some numerical dissipation and study its effect on the wall modeling approach. The last part is dedicated to turbulent inflow generation for WMLES. We select a method based on synthetic perturbation combined with a dynamic control term. We validate this method on WMLES computations of a flat plate turbulent boundary layer and a hot jet-in-cross-flow representative of an industrial configuration. In both cases, we show that a realistic turbulent boundary layer is generated at a small distance downstream from the inlet plane.

Made available in DSpace on 2016-06-02T20:00:16Z (GMT). No. of bitstreams: 1 DissAVF.pdf: 3142723 bytes, checksum: d32fec625d6a407ea812f6bfdadc0c46 (MD5) Previous issue date: 2006-02-28 / The main purpose of this work was to identify and to estimate the rainfall derived infiltration and inflow (IADP) into the sewer in a small city and to do an analysis of their influence on this collection system. This work was composed by field measurements on the sewage flowrate output and volume arriving to the Sewage Pumping Plant Station, simultaneously to the collection and measurement of rainfall on the corresponding same urban watershed area of the Borborema, in São Paulo State. The existing methodologies were divided in the follow steps: choosing and characterization of the working field; data collection of the sewage volume and flowrate; collection of the rainfall data; choosing and characterization of the data collected; employment of existing models and methodologies useful to the present available data, in order to derive the underground water infiltration rate and the overflow occurring in the sewage colletion network. The volumetric and percentile IADP were quantified. The constant unitary rate (TUC) was also estimated, by several ways. The results allowed obtaining mathematical formulations to derive the IADP and TUC of the Borborema s sewage network. Such mathematical formulations are suitable to be applied in urban areas of cities of a similar to that of Borborema. It was estimated that the IADP can generate flowrates 2,5 times greater than the sewage flows in dry weather and infiltration rates in the sewage network similar to those adopted for system design. The work allowed to estimate how complex are the infiltration and inflow of stormwater in the sewer network. The methodologies applied were quite simple and may be easily applied in other cities. / O objetivo precípuo desta pesquisa foi identificar e estimar a infiltração e o afluxo devidos da precipitação (IADP) na rede de esgoto sanitário em município de pequeno porte e efetuar uma análise da sua influência no sistema de esgotamento sanitário. Este trabalho foi realizado através da medição em campo de vazão e volume de esgoto sanitário a montante da EEE Estação Elevatória de Esgoto, simultaneamente com a coleta e medição da chuva precipitada na correspondente área urbanizada da bacia hidrográfica da cidade de Borborema/SP. As metodologias empregadas foram divididas nas seguintes fases: escolha e caracterização do local da pesquisa; coleta de dados de vazão e volume dos efluentes de esgotos sanitários e coleta de dados de precipitação de chuva no local do estudo; seleção e caracterização dos dados coletados; aplicação das metodologias e modelagens existentes possíveis de aplicar em função dos dados disponíveis, para a obtenção da taxa de infiltração das águas subterrâneas e da sobrecarga na rede de esgoto sanitário. Quantificou-se o IADP volumétrica e percentualmente. Calculou-se também a taxa unitária constante (TUC), sob diferentes formatos. Os resultados desta pesquisa permitiram a obtenção de equações matemáticas para avaliação da IADP e da TUC do sistema de esgoto da cidade de Borborema que possivelmente poderão ser aplicadas em áreas urbanizadas de outras cidades do mesmo porte. Estimou-se que a IADP pode gerar volumes 2,5 vezes maiores que o volume de esgotos em tempo seco, bem como taxas de infiltração na rede coletora próximas àquelas adotadas para cálculo da rede. O trabalho possibilitou avaliar quão complexos são a infiltração e o afluxo de águas de chuva na rede de esgoto sanitário. Os métodos empregados, tanto de coleta quanto de modelagem, foram muito simples e podem ser aplicados em outras cidades com certa facilidade.

This diploma´s thesis is focusing on financial management of the construction order. First part of diploma´s thesis is dealing with financial management, financial analysis and management options. The practical part discusses financial plan, economic results and financial analysis of particular construction orders, which are evaluated within one year. The objective of the thesis aims to analyze impacts on the operating economy and evaluate construction contract in context of a construction company. The result is to evaluate financial analyses of construction orders and company´s too.

The thesis is divided into literary research and practical part (own measurement). The content of the literary research is a description of the flow over thin-plate rectangular weir. The practical part is focused on a description of the model, measuring equipment and measurement. The results are evaluation of lower and upper surface of nappe, determination of discharge coefficient, coefficient of relative length of shaft, limit value of relative length of shaft for uninfluenced shape of nappe.