Análisis en sistemas eléctricos en microsatélites. Desarrollo de módulos para una Concurrent Design Facility (CDF) para desarrollo y análisis de misiones espaciales = Analysis of microsatellites power subsystems (battery testing). Development and programming of a new Orbit Design Module for a space mission Concurrent Design Facility (CDF)

El objetivo de este trabajo de fin de grado es la exposición de los resultados y conclusiones, fruto de las tareas desarrolladas durante las practicas curriculares en el Instituto Universitario de Microgravedad “Ignacio Da Riva” (IDR/UPM) el presente curso académico. La estructura del trabajo se compone de dos bloques diferenciados entre sí: el seguimiento de una batería y el desarrollo de un módulo para una CDF.

Environmental analysis of a Concentrated Solar Power (CSP) plant hybridised with different fossil and renewable fuels

The environmental performance of a 50 MW parabolic trough Concentrated Solar Power (CSP) plant hybridised with different fuels was determined using a Life Cycle Assessment methodology. Six different scenarios were investigated, half of which involved hybridisation with fossil fuels (natural gas, coal and fuel oil), and the other three involved hybridisation with renewable fuels (wheat straw, wood pellets and biogas). Each scenario was compared to a solar-only operation. Nine different environmental categories as well as the Cumulative Energy Demand and the Energy Payback Time (EPT) were evaluated using Simapro software for 1 MWh of electricity produced. The results indicate a worse environmental performance for a CSP plant producing 12% of the electricity from fuel than in a solar-only operation for every indicator, except for the eutrophication and toxicity categories, whose results for the natural gas scenario are slightly better. In the climate change category, the results ranged between 26.9 and 187 kg CO2 eq/MWh, where a solar-only operation had the best results and coal hybridisation had the worst. Considering a weighted single score indicator, the environmental impact of the renewable fuels scenarios is approximately half of those considered in fossil fuels, with the straw scenario showing the best results, and the coal scenario the worstones. EPT for solar-only mode is 1.44 years, while hybridisation scenarios EPT vary in a range of 1.72 -1.83 years for straw and pellets respectively. The fuels with more embodied energy are biomethane and wood pellets.

Hybridizing concentrated solar power (CSP) with biogas and biomethane as an alternative to natural gas: Analysis of environmental performance using LCA

Concentrating Solar Power (CSP) plants typically incorporate one or various auxiliary boilers operating in parallel to the solar field to facilitate start up operations, provide system stability, avoid freezing of heat transfer fluid (HTF) and increase generation capacity. The environmental performance of these plants is highly influenced by the energy input and the type of auxiliary fuel, which in most cases is natural gas (NG). Replacing the NG with biogas or biomethane (BM) in commercial CSP installations is being considered as a means to produce electricity that is fully renewable and free from fossil inputs. Despite their renewable nature, the use of these biofuels also generates environmental impacts that need to be adequately identified and quantified. This paper investigates the environmental performance of a commercial wet-cooled parabolic trough 50 MWe CSP plant in Spain operating according to two strategies: solar-only, with minimum technically viable energy non-solar contribution; and hybrid operation, where 12 % of the electricity derives from auxiliary fuels (as permitted by Spanish legislation). The analysis was based on standard Life Cycle Assessment (LCA) methodology (ISO 14040-14040). The technical viability and the environmental profile of operating the CSP plant with different auxiliary fuels was evaluated, including: NG; biogas from an adjacent plant; and BM withdrawn from the gas network. The effect of using different substrates (biowaste, sewage sludge, grass and a mix of biowaste with animal manure) for the production of the biofuels was also investigated. The results showed that NG is responsible for most of the environmental damage associated with the operation of the plant in hybrid mode. Replacing NG with biogas resulted in a significant improvement of the environmental performance of the installation, primarily due to reduced impact in the following categories: natural land transformation, depletion of fossil resources, and climate change. However, despite the renewable nature of the biofuels, other environmental categories like human toxicity, eutrophication, acidification and marine ecotoxicity scored higher when using biogas and BM.

Methodology for Dynamic Stability and Robustness Analysis of Commercial-Power-Module-Based DC-Distributed Systems

El propósito de esta tesis es presentar una metodología para realizar análisis de la dinámica en pequeña señal y el comportamiento de sistemas de alimentación distribuidos de corriente continua (CC), formados por módulos comerciales. Para ello se hace uso de un método sencillo que indica los márgenes de estabilidad menos conservadores posibles mediante un solo número. Este índice es calculado en cada una de las interfaces que componen el sistema y puede usarse para obtener un índice global que indica la estabilidad del sistema global. De esta manera se posibilita la comparación de sistemas de alimentación distribuidos en términos de robustez. La interconexión de convertidores CC-CC entre ellos y con los filtros EMI necesarios puede originar interacciones no deseadas que dan lugar a la degradación del comportamiento de los convertidores, haciendo el sistema más propenso a inestabilidades. Esta diferencia en el comportamiento se debe a interacciones entre las impedancias de los diversos elementos del sistema. En la mayoría de los casos, los sistemas de alimentación distribuida están formados por módulos comerciales cuya estructura interna es desconocida. Por ello los análisis presentados en esta tesis se basan en medidas de la respuesta en frecuencia del convertidor que pueden realizarse desde los terminales de entrada y salida del mismo. Utilizando las medidas de las impedancias de entrada y salida de los elementos del sistema, se puede construir una función de sensibilidad que proporciona los márgenes de estabilidad de las diferentes interfaces. En esta tesis se utiliza el concepto del valor máximo de la función de sensibilidad (MPC por sus siglas en inglés) para indicar los márgenes de estabilidad como un único número. Una vez que la estabilidad de todas las interfaces del sistema se han evaluado individualmente, los índices obtenidos pueden combinarse para obtener un único número con el que comparar la estabilidad de diferentes sistemas. Igualmente se han analizado las posibles interacciones en la entrada y la salida de los convertidores CC-CC, obteniéndose expresiones analíticas con las que describir en detalle los acoplamientos generados en el sistema. Los estudios analíticos realizados se han validado experimentalmente a lo largo de la tesis. El análisis presentado en esta tesis se culmina con la obtención de un índice que condensa los márgenes de estabilidad menos conservativos. También se demuestra que la robustez del sistema está asegurada si las impedancias utilizadas en la función de sensibilidad se obtienen justamente en la entrada o la salida del subsistema que está siendo analizado. Por otra parte, la tesis presenta un conjunto de parámetros internos asimilados a impedancias, junto con sus expresiones analíticas, que permiten una explicación detallada de las interacciones en el sistema. Dichas expresiones analíticas pueden obtenerse bien mediante las funciones de transferencia analíticas si se conoce la estructura interna, o utilizando medidas en frecuencia o identificación de las mismas a través de la respuesta temporal del convertidor. De acuerdo a las metodologías presentadas en esta tesis se puede predecir la estabilidad y el comportamiento de sistemas compuestos básicamente por convertidores CC-CC y filtros, cuya estructura interna es desconocida. La predicción se basa en un índice que condensa la información de los márgenes de estabilidad y que permite la obtención de un indicador de la estabilidad global de todo el sistema, permitiendo la comparación de la estabilidad de diferentes arquitecturas de sistemas de alimentación distribuidos. ABSTRACT The purpose of this thesis is to present dynamic small-signal stability and performance analysis methodology for dc-distributed systems consisting of commercial power modules. Furthermore, the objective is to introduce simple method to state the least conservative margins for robust stability as a single number. In addition, an index characterizing the overall system stability is obtained, based on which different dc-distributed systems can be compared in terms of robustness. The interconnected systems are prone to impedance-based interactions which might lead to transient-performance degradation or even instability. These systems typically are constructed using commercial converters with unknown internal structure. Therefore, the analysis presented throughout this thesis is based on frequency responses measurable from the input and output terminals. The stability margins are stated utilizing a concept of maximum peak criteria, derived from the behavior of impedance-based sensitivity function that provides a single number to state robust stability. Using this concept, the stability information at every system interface is combined to a meaningful number to state the average robustness of the system. In addition, theoretical formulas are extracted to assess source and load side interactions in order to describe detailed couplings within the system. The presented theoretical analysis methodologies are experimentally validated throughout the thesis. In this thesis, according to the presented analysis, the least conservative stability margins are provided as a single number guaranteeing robustness. It is also shown that within the interconnected system the robust stability is ensured only if the impedance-based minor-loop gain is determined at the very input or output of each subsystem. Moreover, a complete set of impedance-type internal parameters as well as the formulas according to which the interaction sensitivity can be fully explained and analyzed, is provided. The given formulation can be utilized equally either based on measured frequency responses, time-domain identified internal parameters or extracted analytic transfer functions. Based on the analysis methodologies presented in this thesis, the stability and performance of interconnected systems consisting of converters with unknown internal structure, can be predicted. Moreover, the provided concept to assess the least conservative stability margins enables to obtain an index to state the overall robust stability of distributed power architecture and thus to compare different systems in terms of stability.

Higher education scholarships as a soft power tool: an analysis of its role in the EU and Singapore. EU Centre Singapore Working Paper No. 23, March 2015

The European Union and Singapore are vastly different entities, each with its own regional and global priorities and policies. Both actors employ a range of tools and instruments to aid in their foreign policy objectives, including in the projection of their soft power. It is worth analysing and comparing the specific instruments of these two actors’ soft power strategies, including but not limited to their stated objectives and perceived effectiveness. This paper will compare the role of higher education and scholarships in diffusing soft power through a comparative case study of the Erasmus Mundus scholarship program and the Singapore Scholarship administered by the Ministry of Foreign Affairs. It will look at the ways in which these programs have shaped the standing of the actors in diffusing their norms and objectives in the regional and international arena. A comparative analysis of these programs will hopefully provide some insight into the proximity between foreign policy-making and higher education internationalisation. This paper will begin with an overview of the aforementioned programs and related schemes, before dissecting and comparing the intent and the policy-making processes behind these, and concludes with a discussion on the present and future role of higher education as a strategic soft power tool.

The power of language and the language of power in M. T. Anderson’s Feed and Gary Stheyngart’s Super Sad True Love Story. A comparative analysis

The aim of my dissertation is to analyze how selected elements of language are addressed in two contemporary dystopias, Feed by M. T. Anderson (2002) and Super Sad True Love Story by Gary Shteyngart (2010). I chose these two novels because language plays a key role in both of them: both are primarily focused on the pervasiveness of technology, and on how the use/abuse of technology affects language in all its forms. In particular, I examine four key aspects of language: books, literacy, diary writing, as well as oral language. In order to analyze how the aforementioned elements of language are dealt with in Feed and Super Sad True Love Story, I consider how the same aspects of language are presented in a sample of classical dystopias selected as benchmarks: We by Yevgeny Zamyatin (1921), Brave New World by Aldous Huxley (1932), Animal Farm (1945) and Nineteen Eighty-Four (1949) by George Orwell, Fahrenheit 451 by Ray Bradbury (1952), and The Handmaid's Tale by Margaret Atwood (1986). In this way, I look at how language, books, literacy, and diaries are dealt with in Anderson’s Feed and in Shteyngart’s Super Sad True Love Story, both in comparison with the classical dystopias as well as with one another. This allows for an analysis of the similarities, as well as the differences, between the two novels. The comparative analysis carried out also takes into account the fact that the two contemporary dystopias have different target audiences: one is for young adults (Feed), whereas the other is for adults (Super Sad True Love Story). Consequently, I also consider whether further differences related to target readers affect differences in how language is dealt with. Preliminary findings indicate that, despite their different target audiences, the linguistic elements considered are addressed in the two novels in similar ways.

Spectral analysis of seabed elevation from the Danish Wadden Sea

Bedforms both reflect and influence shallow water hydrodynamics and sediment dynamics. A correct characterization of their spatial distribution and dimensions is required for the understanding, assessment and prediction of numerous coastal processes. A method to parameterize geometrical characteristics using two-dimensional (2D) spectral analysis is presented and tested on seabed elevation data from the Knudedyb tidal inlet in the Danish Wadden Sea, where large compound bedforms are found. The bathymetric data were divided into 20x20 m areas on which a 2D spectral analysis was applied. The most energetic peak of the 2D spectrum was found and its energy, frequency and direction were calculated. A power-law was fitted to the average of slices taken through the 2D spectrum; its slope and y-intercept were calculated. Using these results the test area was morphologically classified into 4 distinct morphological regions. The most energetic peak and the slope and intercept of the power-law showed high values above the crest of the primary bedforms and scour holes, low values in areas without bedforms, and intermediate values in areas with secondary bedforms. The secondary bedform dimensions and orientations were calculated. An area of 700x700 m was used to determine the characteristics of the primary bedforms. However, they were less distinctively characterized compared to the secondary bedforms due to relatively large variations in their orientations and wavelengths. The method is thus appropriate for morphological classification of the seabed and for bedform characterization, being most efficient in areas characterized by bedforms with regular dimensions and directions.

Analysis of a power failure incident for the preliminary conceptual design of the small pressurized water reactor /

"Contract No. AT(40-1)-2589."

Analysis of probability distributions and power spectra of time histories of maneuvering flight.

"Bureau of Naval Weapons Contract Noa(s) 60-6114-c."

Ameren Illinois Power Company workforce adequacy analysis report /

"December 2008"--Colophon.

The power of deception unveiled, and the man of sin revealed, in an analysis of the book of Revelations. To which is prefixed An essay on the system of man.

Edited by Joseph Churchman.

The works of William Ellery Channing, D.D. : including his Analysis of the character of Napoleon Bonaparte, Thoughts on power and greatness, Remarks on the character of Milton, Sermons, and two pieces never heretofore published in this country.

Mode of access: Internet.

An analysis of trade union power : structure and conduct of the American labor movement /

Typescript.

Supplement to An analysis of the constitution of the East-India company: and of the laws passed by Parliament for the government of their affairs, athome and abroad. To which is prefixed, a brief history of the company, and of the rise and progress of the British power in India /

Mode of access: Internet.