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The particular study case in this thesis is the shock test performed on the LISA Pathfinder satellite conducted in a laboratory environment on a dedicated test bed: Vega Shock Test Apparatus (VESTA). This test is considered fully representative to study shock levels produced by fairing jettisoning event at Vega Launcher Vehicle, which induces high shock loads towards the satellite. In the frame of this thesis, some transient response analyses have been conducted in MSC Nastran, and a shock simulation tool for the VESTA test configuration has been developed. The simulation tool is based on Nastran Direct Transient Response Analysis solver (SOL 109), and is representative of the upper composite of Vega with the LISA Pathfinder coupled to it. Post-processing routines of transient response signals were conducted in Dynaworks which served to calculate Shock Response Spectra (SRS). The simulation tool is a model of forcing function parameters for transient analysis which adequately correlates with the shock real test data, in order to understand how the effect of shock generated by the launcher is seen in the satellite and its sub-systems. Since available computation resources are limited the parameters for analysis were optimised for computation time, file size, memory capacity,  and model complexity. The forcing function represents a release of the HSS clamp band which is responsible for fairing jettisoning, thus the parameters which were studied are mostly concerning the modelling of this event. Among many investigated, those which visibly improved SRS correlation are radial forcing function shape, implementation of axial impulse, clamp band loading geometry and refined loading scheme. Integration time step duration and analysis duration were also studied and found to improve correlation.  From each analysis, the qualifying shock environment was then derived by linear scaling in proportion of the applied preload, and considering a qualification margin of 3dB. Consecutive tracking of structural responses along shock propagation path exposed gradual changes in responses pattern and revealed an important property that a breathing mode (n = 0) at the base of a conical Adapter translates into an axial input to the spacecraft. The parametrisation itself was based on responses registered at interfaces located in near-field (where the clamp band is located and forcing function is applied) and medium-field with respect to the shock event location. Following shock propagation path, the final step was the analysis of shock responses inside the satellite located in a far-field region, which still revealed a very good correlation of results. Thus, it can be said that parametrisation process was adequate, and the developed shock simulation tool can be qualified. However, due to the nature of shock, the tool cannot fully replace VESTA laboratory test, but can support shock assessment process and preparation to such test. In the last part of the thesis, the implementation of some finite element model improvements is investigated. Majority of the panels in spacecraft interior exhibited shock over-prediction due to finite element model limitation. Equipment units modelled as lump masses rigidly attached with RBE2 elements to the panel surface are a source of such local over-predictions. Thus, some of the units were remodelled and transient responses were reinvestigated. It was found that remodelling with either solid elements, or lump mass connected to RBE3 element and reinforced by RBE2 element, can significantly improve local transient responses. This conclusion is in line with conclusions found in ECSS Shock Handbook.

Orientador: Percival Bueno de Araujo / Resumo: As perturbações ou variações de carga produzem oscilações eletromecânicas que devem ser amortecidas o mais rápido possível para garantir confiabilidade e estabilidade da rede. Neste trabalho apresenta-se uma análise do dispositivo FACTS Interline Power Flow Controller (IPFC) e o controlador Proporcional Integral (PI) no gerenciamento dos fluxos de potência e a influência dos Estabilizadores do Sistema de Potência (ESP) e do IPFC Power Oscillation Damping (POD) sobre a estabilidade do sistema elétrico de potência. Neste trabalho enfoca-se nos estudos de estabilidade a pequenas perturbações usando um Algoritmo Genético Adaptativo com Hiper-mutação (AGAH) para ajustar os parâmetros dos controladores suplementares de amortecimento, o Estabilizador de sistema de potência (ESPs) e o Power Oscillation Damping (POD) em forma coordenada. O AGAH tem como objetivo encontrar os parâmetros ótimos do controlador para melhorar o amortecimento fraco das oscilações de baixa frequência locais e inter-área. Neste trabalho representa-se o sistema de elétrico de potência com a inclusão do dispositivo Interline Power Flow Controller com o modelo de sensibilidade de corrente (MSC). Considera-se como sistema teste o sistema Simétrico de Duas Áreas e o sistema New England como o intuito de avaliar o algoritmo proposto. As simulações são feitas no ambiente do MatLab. Por fim, apresenta-se a comparação do algoritmo genético com o desempenho do algoritmo proposto. / Abstract: Small-magnitude disturbances happen to produce electro-mechanical oscillations which should be damped as quickly as possible to ensure reliability and stability of the network. This work presents an analysis of Interline Power Flow Controller (IPFC) FACTS device and PI controller to control and manage power flow and also how Power System Stabilizers and IPFC Power Oscillations Damping (POD) controller influence over an electric power system stability. This work focuses on small-signal stability studies using an Adaptive Genetic Algorithm with Hyper-mutation (AGAH) in order to tune controller parameters in a coordinated way ensuring proper damping. AGAH aims to find optimal controller parameters to enhance the poor damping of local and inter-area low frequency oscillations. This works represents the electric power system and Interline Power Flow Controller device by a current sensitivity model (CSM). This paper considers two areas 14 bus symmetrical power system and New England power system in order to assess proposed algorithm. Coding and Simulations take place in MatLab platform. AGAH and GA get compared by time convergence and performance. This paper shows AGAH is an interesting optimization technique which outweighs GA. / Mestre

Malaysia is a transition economic country that aims to be a developed country by 2020. In realising this mission (Vision 2020), the cluster concept has been an interest and adopted by the central authorities. There are few years ahead to reach the targeted year and it interest of this study to investigate the relevant development on its own engineered cluster of the Multimedia Super Corridor (MSC) that was put forward on the success of Silicon Valley in the US. This thesis focuses on the development of the MSC cluster in the Malaysia context. It examines and measures the state of the cluster, the role played by its core actors (from Triple Helix perspective) and their relationship in the MSC. The role of collaboration has been used to measure the relationship among actors with the key determinants of cluster formation. A mixed data collection method was used to answer the research question and objectives involved. A conceptual model for analysing the MSC cluster is proposed, bringing together insights from the literature on clusters, role of actors, collaborative relationship and the complex systems of innovation approach. This conceptual model uncover the weaknesses of social dimension (social infrastructure) in Porter’s diamond model and the general approach of Triple Helix model in the cluster development. The cluster lifecycle model is used to add the depth to the analysis on the condition of cluster development.

This Master Thesis is the research done in the country of Rwanda. The project leads to study the climate of this country in order to establish whether this climate could be used to produce energy from air and to implement the first wind turbine for serving the nation.   After an introduction about the historical background of wind power, the thesis work deals with assessment of wind energy potential of Rwanda in focusing of the most suitable place for wind power plants. The best location with annual mean wind speed, the rate of use of turbine with hub height for an annual production per year, the mean wind speeds for 6 sites of Rwanda based on ECMWF for climatic data for one year at relief of altitude of 100m and coordinates are reported too.   The result of energy produced and calculations were done based on power hitting wind turbine generator in order to calculate Kinetic energy and power available at the best location to the measurement over the period of 12 months, that could be hoped for long term.   With help of logarithmic law, where wind speed usually increases with increasing in elevation and the desired wind speeds at all 6 sites were used. The annual energy production was taken into account at the best site with desired wind speed at the initial cost of turbine as well as the cost of energy (COE).However, with comparison of the tariff of EWSA, the price of Wind designed in this Research per kWh is cheaper and suitable for people of Rwanda. / <p><em>Rwanda has considerable opportunities development energy from hydro sources, methane gas, solar and peat deposits. Most of these energy sources have not been fully exploited, such as solar, wind and geothermal. As such wood is still being the major source of energy for 94 per cent of the population and imported petroleum products consume more than 40 per cent of foreign exchange. Energy is a key component of the Rwandan economy. It is thus recognized that the current inadequate and expensive energy supply constitutes a limiting factor to sustainable development. Rwanda’s Vision 2020 emphasizes the need for economic growth, private investment and economic transformation supported by a reliable and affordable energy supply as a key factor for the development process. To achieve this transformation, the country will need to increase energy production and diversify into alternative energy sources. Rwandan nations don’t have small-scale solar, wind, and geothermal devices in operation providing energy to urban and rural areas. These types of energy production are especially useful in remote locations because of the excessive cost of transporting electricity from large-scale power plants. The application of renewable energy technology has the potential to alleviate many of the problems that face the people of Rwanda every day, especially if done so in a sustainable manner that prioritizes human rights.</em></p>