No description available.

Aujourd'hui, l'électrification des véhicules constitue une des solutions mises en œuvre par les constructeurs automobiles dans la lutte contre les émissions de gaz polluants et pour la réduction des consommations. Comme le prix des aimants terres rares a fortement augmenté ces dernières années, les moteurs électriques sans aimants permanents sont attractifs, comme les moteurs asynchrones, synchrones à rotor bobiné, à réluctance variable (double saillance ou synchrone). Dans cette thèse, les machines asynchrones et synchrones à réluctance variable sont étudiées et comparées pour des véhicules électriques. Ces deux machines ont un coût faible et possèdent des structures de puissance et de contrôles similaires.Des modèles analytiques non linéaires de machines asynchrones et synchrones à réluctance variable sont établis et validés. En outre, leurs modèles économiques et mécaniques sont également mis en œuvre. Sur la base des modèles analytiques établis, la géométrie et les paramètres de commande des machines étudiées sont dimensionnés afin de réduire les pertes énergétiques durant des cycles de conduite. Une optimisation bi-objective est proposée afin de minimiser en même temps les pertes énergétiques et le coût du moteur. Enfin, les machines optimisées sont comparées, à l’aide de Fronts de Pareto, pour évaluer leurs performances électriques, énergétiques et économiques. / Today, the concerns of the energy crisis and the reduction of gas emissions stimulate the research in several electric vehicle domains. As the cost of rare earth magnetic materials has increased significantly in recent years, electrical motors without permanent magnets draw more attention, such as induction motors, wound-synchronous motors, switched reluctance motors, and synchronous reluctant motors. In this thesis, induction and synchronous reluctant machines are chosen to be studied for the electric vehicle traction application since they are low costly and fed up with similar power electronics and control strategies.Nonlinear analytical models of induction and synchronous reluctant machines are established and validated. Besides, economical and mechanical models are developed as well. Based on established analytical models, the geometry and the control parameters of these studied machines are calculated to define the total energy losses during the driving cycle. A bi-objective optimization is carried out to minimize total energy losses and motor costs. At last, the optimized machines are compared from their electric, energetic and economic performances, with the help of the Pareto Fronts obtained.

[pt] O teste de injetividade consiste em injetar uma fase, usualmente água, em um reservatório de óleo para coletar informações sobre ele. Conhecer os parâmetros do reservatório pode ser valioso para melhorar a produção de óleo. Muitos estudos têm sido apresentados a respeito do comportamento da pressão em reservatórios multicamadas sob escoamento de fluxo monofásico e, também, durante os testes de injetividade. No entanto, uma solução analítica para o comportamento da pressão em reservatórios de múltiplas camadas durante os testes de injetividade é bem conhecida apenas quando o fluxo cruzado de formação não é considerado. Portanto, o presente trabalho apresenta um modelo analítico no espaço de Laplace para reservatórios radialmente compostos multicamadas considerando o fluxo cruzado de formação sob fluxo monofásico e, então, para reservatórios multicamadas com fluxo cruzado de formação sob fluxo bifásico. A precisão da solução proposta foi verificada através da comparação com um simulador numérico de fluxo. Os resultados fornecidos pelo modelo analítico e pelos dados numéricos foram consistentemente semelhantes. Além disso, os dados obtidos pela solução analítica foram utilizados para estimar a permeabilidade equivalente do reservatório. Os valores calculados apresentaram uma aproximação satisfatória para todos os casos. / [en] The injectivity test consists of injecting a phase, usually water, into an oil reservoir in order to collect information about it. Knowing these reservoir s parameters can be valuable in order to improve oil production. Many studies have been presented regarding the behavior of pressure in multilayered reservoirs under single phase fluid flow and, also, during injectivity tests. However, an analytical solution for pressure behavior in multilayered reservoirs during injectivity tests is well known only when the formation crossflow is not considered. Therefore, the present work attempts to develop an analytical model in the Laplace space for multilayered radially composite reservoirs with formation crossflow under single phase fluid flow, and then, for multilayered reservoirs with formation crossflow under two phase fluid flow. The accuracy of the proposed solution was verified by comparison with a finite difference flow simulator. The results provided by the analytical model and by the numerical data were consistently similar. Furthermore, the data obtained by the analytical solution was used to estimate the reservoir s equivalent permeability. Calculated values presented a satisfactory accuracy for all cases.

Due to the increasing number of components involved in Radio Frequency design, integration and packaging become an important topic of developing power-efficient and cost-effective solutions. Furthermore, interconnections are a key factor in such a topic because they are heavily used in Radio Frequency engineering, especially in the Fifth Generation. Among the interconnections, bond wires are one of the most commonly used.In micro assembly design, it is crucial to understand and model the behavior of each component, including interconnections. Radio Frequency engineers usually use the bond wire models in the software directly without questioning if the model actually has the same behavior as the fabricated one. Therefore, how to accurately model and characterize the bond wires becomes valuable, and furthermore, how the physical dimensions affect the transmission performance. This Master’s thesis project aims to solve this problem by building simple models for single bond wire and double bond wires with coupling, and verifying them by electromagnetic simulation and measurement.The project has built bond wire models in Matlab and in electromagnetic simulators NI AWR and ANSYS HFSS. The actual test structures are also fabricated using the bonding machine, and measured by vector network analyzer. A sufficient amount of data has been collected from these sources and then analyzed. The proposed analytical model of bond wires is valid after comparing its results with those from simulation and measurement. In addition, the effect of the loop height and separation distance on the transmission performance is studied and has a well verified conclusion.This thesis work will be helpful to Radio Frequency engineers, who use bond wires in the micro assembly of their design. They would be able to characterize the bond wires more accurately and adjust the physical dimensions in order to achieve the desired performance. / På grund av det ökande antalet komponenter i radiofrekvensdesign, integration och förpackning blivit ett viktigt ämne för att utveckla energieffektiva och kostnadseffektiva lösningar. Sammankopplingar är en nyckelfaktor i ett sådant ämne, eftersom de är starkt används i radiofrekvensteknik. Bland dem, bondtrådar är en av de vanligaste.Det är viktigt att förstå och modellera beteendet hos varje komponent. Därför hur att noggrant modellera och karakterisera bondtrådarna blir ett värdefullt problem, och dessutom, hur de fysiska dimensionerna påverkar överföringsprestanda.Projektet har byggt bondtrådsmodeller i Matlab och i elektromagnetiska simulatorer NI AWR och ANSYS HFSS. De faktiska teststrukturerna tillverkas också med hjälp av bindningsmaskinen och mäts av vektornätverksanalysatorn. Den föreslagna analysmodellen för bindningstrådar är giltig efter att ha jämfört dess resultat med dem från simulering och mätning. Dessutom studeras effekten av slinghöjden och separationsavståndet på transmissionens prestanda och har en väl verifierad slutsats.

Since the field of computer networks has rapidly grown in the last two decades, congestion control of traffic loads within networks has become a high priority. Congestion occurs in network routers when the number of incoming packets exceeds the available network resources, such as buffer space and bandwidth allocation. This may result in a poor network performance with reference to average packet queueing delay, packet loss rate and throughput. To enhance the performance when the network becomes congested, several different active queue management (AQM) methods have been proposed and some of these are discussed in this thesis. Specifically, these AQM methods are surveyed in detail and their strengths and limitations are highlighted. A comparison is conducted between five known AQM methods, Random Early Detection (RED), Gentle Random Early Detection (GRED), Adaptive Random Early Detection (ARED), Dynamic Random Early Drop (DRED) and BLUE, based on several performance measures, including mean queue length, throughput, average queueing delay, overflow packet loss probability, packet dropping probability and the total of overflow loss and dropping probabilities for packets, with the aim of identifying which AQM method gives the most satisfactory results of the performance measures. This thesis presents a new AQM approach based on the RED algorithm that determines and controls the congested router buffers in an early stage. This approach is called Dynamic RED (REDD), which stabilises the average queue length between minimum and maximum threshold positions at a certain level called the target level to prevent building up the queues in the router buffers. A comparison is made between the proposed REDD, RED and ARED approaches regarding the above performance measures. Moreover, three methods based on RED and fuzzy logic are proposed to control the congested router buffers incipiently. These methods are named REDD1, REDD2, and REDD3 and their performances are also compared with RED using the above performance measures to identify which method achieves the most satisfactory results. Furthermore, a set of discrete-time queue analytical models are developed based on the following approaches: RED, GRED, DRED and BLUE, to detect the congestion at router buffers in an early stage. The proposed analytical models use the instantaneous queue length as a congestion measure to capture short term changes in the input and prevent packet loss due to overflow. The proposed analytical models are experimentally compared with their corresponding AQM simulations with reference to the above performance measures to identify which approach gives the most satisfactory results. The simulations for RED, GRED, ARED, DRED, BLUE, REDD, REDD1, REDD2 and REDD3 are run ten times, each time with a change of seed and the results of each run are used to obtain mean values, variance, standard deviation and 95% confidence intervals. The performance measures are calculated based on data collected only after the system has reached a steady state. After extensive experimentation, the results show that the proposed REDD, REDD1, REDD2 and REDD3 algorithms and some of the proposed analytical models such as DRED-Alpha, RED and GRED models offer somewhat better results of mean queue length and average queueing delay than these achieved by RED and its variants when the values of packet arrival probability are greater than the value of packet departure probability, i.e. in a congestion situation. This suggests that when traffic is largely of a non bursty nature, instantaneous queue length might be a better congestion measure to use rather than the average queue length as in the more traditional models.

При выборе программного обеспечения, применяемого в технологиях информационного моделирования в области строительства, следует учитывать немало факторов: как возможности программного комплекса в среде разработки, так и способность выполнять специализированные расчеты и анализ по данным проекта. В диссертации рассмотрены нюансы построения корректной архитектурной модели в ArchiCAD, исследованы методы ее экспорта в ЛИРА-САПР для расчета несущих конструкций из сборного железобетона, разработаны методические рекомендации по созданию архитектурной модели, которые позволяют избежать ошибок и трудностей при передачи на расчет, а также помогают оптимизировать работу Научно-проектной компании «АСПект». / At the stage of selecting information modeling software in the field of construction, many factors should be taken into account such as the capabilities of the software complex in the development environment, and the ability to perform specialized calculations and analysis according to project data. The dissertation considers the nuances of correct architectural model building in ArchiCAD, researches the methods of its export to LIRA-CAD for calculating load-bearing structures from precast reinforced concrete, developed methodological recommendations for creating an architectural model that avoid errors and difficulties in transferring to calculation, and also help optimize the work of the Scientific and Design Company "ASPekt."

The presence of vegetation in open channel flow has a significant influence on flow resistance, turbulence structures and sediment transport. This study will evaluate flow resistance and scale velocity profile in depth limited flow conditions, specifically investigating the impact of vegetation on the flow resistance under submerged flow conditions. The resistance induced by vegetation in open channel flows has been interpreted differently in literature, largely due to different definitions of friction factors or drag coefficients and the different Reynolds numbers. The methods utilized in this study are based on analytical and numerical models to investigate the effects of vegetation presence on flow resistance in open channel flows. The performing strategy approach was applied by three-dimensional computational fluid dynamics (CFD) simulations, using artificial cylinders for the velocity profile. This is to estimate the average flow velocity and resistance coefficients for flexible vegetation, which results in more accurate flow rate predictions, particularly for the case of low Reynolds number. This thesis shows different formulas from previous studies under certain conditions for a length scale metric, which normalises velocity profiles of depth limited open channel flows with submerged vegetation, using both calculated and simulated model work. It considers the submerged vegetation case in shallow flows, when the flow depth remains no greater than twice the vegetation height. The proposed scaling has been compared and developed upon work that have been influenced by logarithmic and power laws to present velocity profiles, in order to illustrate the variety of flow and vegetation configurations.

No description available.

В диссертации были изучены особенности использования методов машинного обучения в сфере страхования. Рассмотрены возможности архитектурного подхода в разработке модели машинного обучения. Осуществлен анализ тенденций цифровой трансформации сферы страхования. Осуществлена оценка результативности использования машинного обучения в страховании. Построена полная модель архитектуры ПАО СК «Росгосстрах». Разработана аналитическая модель машинного обучения в сфере тарификации страховой компании. На основе процессного подхода детально рассмотрены все фазы проекта по внедрению модели машинного обучения в деятельность страховой компании. Разработана и реализована имитационная модель управления проектом разработки и внедрения модели машинного обучения в деятельность страховой компании на основе различных сценарием. / The dissertation studied the features of using machine learning methods in the field of insurance. The possibilities of the architectural approach in the development of a machine learning model are considered. The analysis of trends in the digital transformation of the insurance industry has been carried out. The effectiveness of the use of machine learning in insurance has been evaluated. A complete model of the architecture of PJSC IC Rosgosstrakh was built. An analytical model of machine learning in the field of tariffing of an insurance company has been developed. Based on the process approach, all phases of the project to introduce a machine learning model into the activities of an insurance company are considered in detail. A simulation model for project management for the development and implementation of a machine learning model in the activities of an insurance company has been developed and implemented based on various scenarios.

[pt] A presente tese de doutorado tem como origem o projeto de pesquisa Aneel PD-0394-1905/2019, realizado a partir de uma colaboração entre Furnas e PUC-Rio. A principal meta desse grande projeto de pesquisa está no desenvolvimento do concreto reforçado com fibras visando sua aplicação em elementos estruturais que estão submetidos à fadiga na flexão ao longo de toda sua vida útil, como torres eólicas, pavimentos e elementos de pontes. Dessa maneira, ao longo de todo essa tese doutorado, a degradação mecânica do concreto reforçado com fibras sob fadiga é analisada em detalhe desde a escala da fibra em ensaios de arrancamento até a escala estrutural através de testes mecânicos de fadiga em larga escala. A primeira etapa desse estudo traz uma análise do comportamento à fadiga do concreto reforçado com fibras. A vida à fadiga desse material é estudada através de diferentes modelos estatísticos, que garantem avaliar a falha do material baseada em uma probabilidade falha. Já os ensaios de fadiga no arrancamento ajudam a explicar na escala interface fibra-matriz como ocorre a ruptura dos prismas sob carregamentos cíclicos. Uma segunda fase desse trabalho mostra a degradação mecânica de vigas armadas sob fadiga e o impacto da adição de fibras nos principais parâmetros de interesse. A adição do reforço fibroso é responsável por causar uma redistribuição de tensões na zona tracionada do elemento estrutural, diminuindo as deformações da armadura longitudinal e amenizando a degradação mecânica do concreto armado em termos de curvatura, deslocamento e rigidez. Além disso, a adição de fibras também é responsável por incrementar significativamente a aderência da barra de aço ao redor da matriz de concreto. Fator chave para explicar a melhora da resposta mecânica da estrutura sob fadiga e estudada nessa tese de doutorado através dos ensaios de arrancamento da barra aço. Por fim, uma nova solução analítica foi desenvolvida para avaliar a degradação mecânica dos prismas de concreto reforçado com fibras sob fadiga. As curvas analíticas propostas se adequaram de forma bem sucedida os resultados experimentais analisados nesse trabalho. A adição de fibras apresentou grande potencial visando uma diminuição da degradação mecânica das estruturas de concreto armado submetidas a carregamentos cíclicos. A redistribuição de tensões na zona tracionada devido às fibras promove uma maior rigidez da estrutura sob fadiga, uma melhora da aderência da armadura e uma maior capacidade de resistir aos ciclos de fadiga ao longo do tempo. Esse ganho mecânico com o reforço fibroso, portanto, pode garantir maior vida útil das estruturas em concreto armado. / [en] This doctoral thesis originates from the research project Aneel PD-0394- 1905/2019, carried out through a collaboration between Furnas and PUC-Rio. The main objective of this extensive research project is the development of fiber reinforced concrete for distinct structural application which are subjected to continuous flexural fatigue loading along their useful life, such wind tower endeavors, concrete pavements and bridge elements. The addition of fibers in the concrete mix has the potential to mitigate the mechanical deterioration along the continuous load cycles, enhancing, as a consequence, the durability and the fatigue life of the cited concrete structural elements. Throughout this doctoral thesis, the mechanical degradation of fiber reinforced concrete under fatigue is carefully analyzed, starting from the fiber scale with pull-out tests and going up to the structural scale through large-scale fatigue mechanical tests. The first stage of this study involves an analysis of the mechanical behavior of fiber reinforced concrete under fatigue loading. The material fatigue life is examined using different statistical models, which allow evaluating material failure based on a failure probability. Fatigue pull-out tests help explain, at the fiber-matrix interface scale, how the prisms rupture under cyclic loading. A second phase of this work demonstrates the mechanical degradation of reinforced structural beams under fatigue and the impact of fiber addition on key concerned parameters. The addition of fiber reinforcement causes a redistribution of stresses in the tension zone of the structural element, reducing the deformations of the longitudinal rebar and mitigating the mechanical degradation of reinforced concrete in terms of curvature, displacement and stiffness. Furthermore, fiber addition significantly improves the bond between the steel bar and the surrounding concrete matrix, a key factor in explaining the enhanced mechanical response of the structure under fatigue, as studied in this doctoral thesis through rebar pull-out tests. Finally, a new analytical solution was developed to assess the mechanical degradation of fiber reinforced concrete prisms under fatigue loads. The proposed analytical curves successfully fit the experimental results analyzed in this work. The addition of fibers showed great potential in reducing the mechanical degradation of reinforced concrete structures subjected to cyclic loading. The stress redistribution in the tension zone, caused by the fibers, promotes greater stiffness of the structure under fatigue, improves the bond with the reinforcement and enhances the ability to withstand fatigue cycles over time. Therefore, the observed enhancement of mechanical properties through fiber reinforcement can ensure a longer service life for reinforced concrete structures.