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Dhavale, Tushar. "Low power laser sintering of iron powder". Thesis, University of the West of England, Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.522529.
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Stone, Michael H., William A. Sands, G. G. Sands, K. C. Pierce i Michael W. Ramsey. "Power and Power Potentiation among Strength Power Athletes". Digital Commons @ East Tennessee State University, 2007. https://dc.etsu.edu/etsu-works/4502.
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Costa, Fernando Manuel Alves Mendonça Pinto da. "Entre o Poder e a Lei. As Constituições Portuguesas de 1933 e 1976". Doctoral thesis, Instituto Superior de Ciências Sociais e Políticas, 2021. http://hdl.handle.net/10400.5/21613.
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Tese de Doutoramento em Ciência PolíticaO poder é um conceito central em Ciência Política. A sua relação com a lei, nomeadamente com a lei máxima, a constituição, é muito próxima. Não é por acaso que, durante muito tempo, Ciência Política, Direito Constitucional e Direito Político se confundiam. Se alguns autores vêem as constituições como o “estatuto do político”, o importante é entender que elas são construídas por poderes presentes em determinado momento histórico-social-político. Será fundamental percorrer os caminhos que nos levam do poder para a lei, indicando-se a feitura das duas últimas constituições portuguesas, como trilho dessa descoberta. Parte-se do tripé conceitos-contextos-ideias e assim, coletando os conceitos de diversos investigadores e ideias chave, como poder, lei, constituição e outras, é fulcral uma contextualização dos “momentos constitucionais” de um ponto de vista social, geopolítico, económico e, evidentemente, histórico. Apetrechados dos conceitos e enquadrados pelos contextos, chegamos às ideias, que nos podem permitir entender o percurso do poder para a lei e, talvez, desenhar novos conceitos que ilustrem melhor este caminho. Se as constituições manifestam no seu articulado, os poderes presentes na sociedade, elas não o fazem de uma forma direta mas através de um processo bastante complexo. As ideias congeminam os poderes e digladiam-se para se afirmarem, mas as vencedoras são já o resultado como que de uma miscigenação, que irá produzir a lei. É assim que poderemos afirmar que a lei não resulta apenas do poder dominante, mas é decorrente de um cadinho de ideias, vencedoras, vencidas e ainda em maturação. Todos os poderes influenciam a formulação das constituições, leis máximas das sociedades, muitas vezes para além da vontade dos seus redatores. As constituições não constituem uma sociedade, mas, de alguma forma, relatam-na explícita e implicitamente, pela tradução dos diversos poderes.
Power is a central concept in Political Science. Its relationship with the law, namely with the maximum law, the constitution, is very close. It is not by chance that, for a long time, Political Science, Constitutional Right and Political Right were confused. If some authors see constitutions as the “statute of the politician», what is important to understand is that they are built by existing powers in a certain historical-social-political moment. It will be fundamental to walk the paths that lead us from power to the law, pointing the execution of the last two Portuguese constitutions, as a trail of this discovery. Starting with the tripod: concepts-contexts-ideas, collecting the concepts of several researchers, and key ideas such as power, law, constitution, and others, it is crucial to contextualize the “constitutional moments” from a social, geopolitical, economic and, of course, historical point of view. Equipped with concepts and framed by contexts, we come to ideas, which can allow us to understand the path of the power to the law and, perhaps, design new concepts that better illustrate this path. If the constitutions manifest in their articles, the existing powers in society, it is not done in a simple way but through a very complex process. The ideas combine the powers and fight each other to assert themselves, but the winners are already the result of a miscegenation that will produce the law. That is how we can affirm that the law is not just the result of dominant power but is the result of a melting pot of ideas: winning ones, losing others and, still in maturation others. All powers influence the formulation of constitutions, the maximum laws of societies, often beyond the will of their editors. Constitutions do not constitute a society but, somehow, they report it explicitly and implicitly, through the translation of the different powers.
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Stone, Michael H., William A. Sands, Kyle C. Pierce, Michael W. Ramsey i G. Gregory Haff. "Power and Power Potentiation among Strength-Power Athletes: Preliminary Study". Digital Commons @ East Tennessee State University, 2008. https://dc.etsu.edu/etsu-works/4138.
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Purpose: To assess the effects of manipulating the loading of successive sets of midthigh clean pulls on the potentiation capabilities of 7 international-level US weightlifters (4 men, 3 women).
Methods: Isometric and dynamic peak-force characteristics were measured with a force plate at 500 Hz. Velocity during dynamic pulls was measured using 2 potentiometers that were suspended from the top of the right and left sides of the testing system and attached to both ends of the bar. Five dynamic-performance trials were used (in the following order) as the potentiation protocol: women at 60, 80, 100, 120, and 80 kg and men at 60, 140, 180, 220, and 140 kg. Trials 2 vs 5 were specifically analyzed to assess potentiation capabilities. Isometric midthigh pulls were assessed for peak force and rate of force development. Dynamic lifts were assessed for peak force (PF), peak velocity (PV), peak power (PP), and rate of force development (RFD).
Results: Although all values (PF, PV, PP, and RFD) were higher postpotentiation, the only statistically higher value was found for PV (ICCα = .95, P = .011, η2 = .69).
Conclusions: Results suggest that manipulating set-loading configuration can result in a potentiation effect when heavily loaded sets are followed by a lighter set. This potentiation effect was primarily characterized by an increase in the PV in elite weightlifters.
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SZANIECKI, BARBARA PECCEI. "POLITICAL POSTER: POWER AND POTENTIAL POWER". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2005. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=7141@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROA iconografia de Luís XIV foi um exemplo de representação da soberania onde a separação espacial e o acabamento perfeito das figuras refletia a organização social e política que a produzia. Contudo, fora da Igreja e do Estado, desenvolveram-se ao longo da modernidade, expressões estéticas opostas à representação do poder transcendental. Ao final do reinado de Luís XIV, surgiu um discurso histórico-político que, após revelar as múltiplas nações que lutam sob o Estado, autodialetizou-se quando, ao reivindicar uma função totalizadora, o Terceiro Estado retomou, de certa maneira, a tese monárquica onde a nação residia inteiramente na pessoa do rei. Esse movimento explicaria uma certa continuidade do discurso visual do poder - dos portraits monárquicos aos republicanos - por um lado e, por outro, a multiplicidade das formas de resistência: os cartazes políticos de maio de 68 foram a expressão das diversas nações contestadoras dos poderes e saberes constituídos daquele momento, manifestando o desejo de proximidade social e de renovação política através de elementos próximos da estética carnavalesca. Na transição contemporânea de uma soberania moderna para uma soberania imperial, a crise político-estético entre transcendência e imanência perdura. Por um lado, monarquia e aristocracia imperial apresentam a unidade transcendental através de recursos estéticos semelhantes. Por outro, no terceiro nível do Império, encontramos expressões estéticas que se afastam radicalmente das representações do poder e que denominamos manifestações de potência a partir da definição sociológica, política e ontológica de multidão.
Louis XIV´s iconography was an example of sovereignty representation in which the spatial separation and the perfect finishing of figures reflected the social and political organization that produced it. However, outside the Church and the State, aesthetic expressions opposed to transcendental representation were developed all along modern times. At the end of Louis XIV´s reign arose a historical-political discourse that, after revealing the multiple nations which fought under the State, dialectized itself when the Thiers- États, in the process of claiming a totalizing function, resumed to a certain extent the monarchic thesis in which the nation dwells entirely in the person of the king. This movement would explain on the one hand, a certain continuity of the visual discourse of power - from the monarchic to the republican portraits - and, on the other hand, the multiplicity forms of resistance: the May 1968 political posters were the expression of the diverse nations, contestant of the powers and knowledge constituted at that moment, and displayed the desire of social proximity and political renewal, through elements close to the aesthetic of Carnival. In the contemporary transition from a modern sovereignty to an imperial one, a politicalaesthetic crisis between transcendentalism and immanentism subsists. On the one hand, monarchy and imperial aristocracy introduce the transcendental unity through similar aesthetic resources. On the other hand, in the Empire third level, we find aesthetic expresions which fundamentally deviate from the representations of power and which we designate display of potential power from the sociological, political and ontological definition of multitude.
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MIRIGALDI, ALESSANDRO. "Power scaling of high power lasersystems". Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2966325.
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Falik, Adam. "Power". ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/1310.
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Liu, Ning. "Our Power over Our Power : A paradigm shift in thederegulated power market". Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-235464.
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A higher share of renewable energy in power generation is one of most ambitious goals for sustainable development under the increasing pressure of climate change. On the deregulated electricity market in Sweden, the consumers are able to choose their electricity from a specific supplier and a specific energy source, which gives them the opportunity to execute their consumer power to have positive impacts on increasing energy efficiency and renewable electricity generation by stopping buying electricity produced from fossil fuels. A new paradigm is thus proposed in this paper which provides a new perspective on purchase of the product electricity. The new paradigm makes electricity a specified product for a specific customer, the electricity audited is never mixed with that not audited, because all electricity which is audited can be traced. The aim of this study is to provide a greater understanding of the new paradigm on the deregulated electricity market. By conducting a willingness to pay survey and several deep interviews, it analyzed the main factors hindering the customers’understanding of the new market dynamics in terms of active choice in ‘green’ electricity and stopping buying fossil electricity. The results and discussions show that the new paradigm could facilitate shedding light on some important implications for strategic decision making in power companies, for policy-makers as well as customers.
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Rothkegel, Lisa. "The power of power : regime dynamics and the Southern African power pool". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79984.
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Thesis (MA)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Electricity is the key to economic growth and numerous aspects of human development. Africa’s installed generation capacity is dire, alongside it being the biggest funding backlog the power sector. There is however hope with the projection that to date, only 7% of this power potential has been harnessed. The increased acknowledgement of the importance of electricity for states to improve along with the knowledge that the capacity is there, has driven states within Southern Africa, to engage in increased and committed cooperation with one another. Within the greater vision of regional integration of the Regional Economic Communities (RECs) in Africa, energy was one of the first formal cooperative arrangements of the Southern African Development Community (SADC), which is the region this study will be focusing on. The form of electricity cooperation adopted was that of the Southern African Power Pool (SAPP), which is geared at increasing cross-border electricity trade and ensuring secure and reliable supply to its members. The study investigates the formation of an electricity regime within Southern Africa, by using the Southern African Power Pool as a case study. In order to properly assess the development of the SAPP, regime theory will be used. An analytical framework, derived from different studies around regime theory has been constructed. This framework assists in the analysis of the formation and evolution of the SAPP, which facilitates the assessment of the type of regime which has emerged, and guides a sound analysis around the degree of the electricity regimes effectiveness. Given the process of formation and characteristics underlying the SAPP, it has been found that it falls within the category of a negotiated regime. The analytical framework provided clear guidelines in assessing the degree of effectiveness regarding the case study at hand. After an analysis of the historical and organisational functioning of the regime - it can be argued that the SAPP is a stable and effective regime, at least on paper. It however faces various challenges, which have constrained its efficient functioning. It is concluded that members of the regime are committed to the SAPP’s continued development despite the problems identified.
AFRIKAANSE OPSOMMING: Elektrisiteit is die sleutel tot ekonomiese groei en baie ander aspekte van menslike ontwikkeling. Afrika se geïnstalleerde opwekkingskapasiteit is net so nypend soos die feit dat dit die grootste befondsing agterstand in die kragvoorsiening sektor is. Daar is egter hoop met die projeksie dat, tot op datum, slegs 7% van hierdie kragpotensiaal benut word. Die toenemende erkenning van die belang van elektrisiteit vir state om vooruit te gaan, gepaard met die wete dat die kapasiteit beskikbaar is, het state binne suider Afrika gedryf om hulle tot toenemende en volgehoue samewerking met mekaar te verbind. Binne die groter visie vir streeksintegrasie van die Streek se Ekonomiese Gemeenskappe (SEG) [Regional Economic Communities (REC)] in Afrika, was energie een van die eerste formele korporatiewe akkoorde van die Suider Afrikaanse Ontwikkelings Gemeenskap (SAOG) [Southern African Development Community (SADC)], wat die streek is waarop hierdie studie sal fokus. Die vorm wat elektrisiteit samewerking aangeneem het, was die Suider Afrika Krag Poel (SAKP) [Southern African Power Pool (SAPP)], wat aangepas is om elektrisiteithandel oor grense heen te bevorder en veilige, asook betroubare lewering aan die lede te verseker. Hierdie studie ondersoek die totstandkoming van ’n elektrisiteit ‘regime’ binne suider Afrika deur die SAKP as ’n gevalle studie te gebruik. Om die ontwikkeling van die SAKP behoorlikte asesseer, sal die regime teorie gebruik word. ’n Analitiese raamwerk, wat afgelei is van verskeie studies met betrekking tot regime teorie, is dus saamgestel. Hierdie raamwerk help met die analise van die totstandkoming en evolusie van die SAKP wat die asessering van die tipe regime, wat ontstaan het, vergemaklik en dit rig ook ‘n streng analise met betrekking tot die graad van effektiwiteit van die elektrisiteit regimes. Gegewe die proses van totstankoming en die eienskappe onderliggend aan die SAKP, is daar bevind dat dit binne die kategorie van ’n onderhandelde regime val (negotiated regime). Die analitiese raamwerk het duidelike riglyne voorsien om die effektiwiteitsgraad, met betrekking tot die gevallestudie, te assesseer. Na ’n analise van die historiese en organisatoriese funksionering van die regime – kan mens aanvoer dat die SAKP, ten minste op skrif, ’n stabiele en effektiewe regime is. Dit staar egter verskeie struikelblokke in die gesig, wat die effektiewe funksionering beperk. Daar kan egter afgelei word dat die lede van die regime toegewyd is tot die volgehoue ontwikkeling van die SAKP, ten spyte van die probleme wat geïdentifiseer is.
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Mir, Cantarellas Antonio. "Competitive power control of distributed power plants". Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/552958.
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Nowadays, the electrical energy sector is currently found in a dramatic changing paradigm, which moves towards an increasing trend in generating power at distribution levels, where electricity is typically consumed, by means of non-conventional/renewable based generation units. These new generation technologies, termed as distributed generation, not only offers a non-pollutant, cheap and efficient source of energy to cover increasing demand, but also enhance the reliability of supply to critical loads and reduce the need for additional grid reinforcements. Aside of the technical benefits provided, distributed generation will massively integrate renewable energy resources, with new type of loads and end-user actors, such as prosumers, demand responsive loads, or electric vehicles. Where these actors will actively participate in energy and auxiliary service markets, depending on their available or constrained energy needs. For this reason, the work presented in this Thesis deals with designing and implementing advanced hierarchical control solutions to renewable-based power plants with the purpose of achieving advanced grid conection performance while reaching maximum economic benefits from its optimum real-time operation. Initially, an extensive analysis on the main renewable-based power plant hierarchical control solutions currently on the shelf, is performed. This study not only covered the specific case of renewable-based power plants, but also advanced microgrid and smart grid control solutions. Once the main renewable-based power plant hierarchical solutions were analized, a novel Hierarchical Distributed Control Structure (HDCS) is proposed for increased management of renewable-based active distributed plants. This hierarchical control structure comprises all possible functional levels from the higher long-term economic scheduling layer, to the instantaneous supervisory control of the resource, emphasizing the entire operation and control functionalities needed for increasing the integration of active distributed power plants. In order to achieve real-time control capabilities in active distribution systems, the present thesis introduces a novel power sharing control strategy, based on the competitive operation of multiple active participating agents (distributed generators, demand response and energy storage systems) through the implementation of market rules. Such control capabilities are satisfied by applying a price control signal over the entire grid control architecture, being the final-end participating agent, the responsible entity in charge of deciding its own generation/demand involvement based on its marginal or affordable electricity costs. In addition, it reduces the information volume to be transmitted and processing requirements, as the higher control levels do not need to have knowledge on the detailed distribution system topology and contributing actors. In order to have a meaningful evaluation of the proposed competitive control capabilities, a wave power plant application has been selected, which constitutes a challenging scenario for the controller itself to achieve advanced real-time control capabilities in such an oscillating renewable energy resource. In order to suitably characterize the wave energy resource profile resulting from maximum energy absorption, this Thesis introduce a novel adaptive vector controller, which maximizes the energy extraction from the resource regardless of the dominant irregular wave frequency characteristics. For the specific wave power plant application considered, the competitive control does not only ensures real-time optimum resource allocation for satisfying a given production objective, but also provides optimum long term operation of the system. As a result, overall plant costs reductions can be achieved under the competitive operation, since the plant scheduled energy is satisfied by making use of the generation units with cheaper cumulative operation costsActualmente, el sector eléctrico se encuentra inmerso en un profundo proceso de restructuración, donde de cada vez más se tiende a generar energía a nivel de distribución, mediante el uso de generación no convencional/renovable. Estas nuevas tecnologías de generación, referidas como generación distribuida, no proporcionan unicamente una fuente de energía no-contaminante, barata y eficiente para cubrir el incremento de demanda, sinó que también pueden proporcionar seguridad de suministro a cargas críticas, así como reducir la necesidad de expansiones futuras de red. Además de las capacidades técnicas proporcionadas, la generación distribuida hará posible la integración masiva de sistemas de generación renovable, con nuevos tipos de cargas y usuarios finales, como prosumidores, cargas regulables, o vehiculos eléctricos, donde todos estos usuarios participaran activamente en mercados de energía y servicios auxiliares, dependiendo de sus requisitos de uso de energía. Por lo tanto, el trabajo realizado en esta tesis se centra en el diseño e implementación de soluciones jerárquicas de control avanzado en plantas de generación renovable, con el objetivo de obtener un comportamiento harmonioso de intercacción con la red, mientras la operación de la planta maximiza los beneficios derivados de su operación en tiempo real. Inicialmente, se ha llevado a cabo una revisión extensa sobre los sistemas de control jerárquico comunmente implementados en plantas de generación renovable, en microredes y en redes inteligentes. Una vez revisados los principales sistemas de control jerárquico en este tipo de aplicaciones, se propone un una novedosa estructura de control, que cubre todos los niveles de control posibles, desde el más alto nivel de gestión económica, hasta el control detallado del recurso de generación. Para lograr capacidades de control en tiempo real en sistemas activos de distribución, la presente tesis propone una nueva estrategia de control de reparto de potencia, basada en la operación competitiva de múltiples agentes participantes activos (generadores distribuidos, respuesta de demanda y sistemas de almacenamiento de energía) mediante la implementación de reglas del mercado. Dichas capacidades de control se satisfacen aplicando una señal de precio a lo largo de toda la arquitectura de control, siendo el agente de final, el ente responsable de decidir su propia participación en la generación/demanda en función de sus propios costes de electricidad marginales o asumibles. Además, reduce el volumen de información a transmitir y los requisitos de procesamiento de datos, ya que los niveles de control más altos no necesitan tener conocimiento sobre la topología del sistema de distribución detallado ni de la contribución de los actores adyacentes. Para llevar a cabo una evaluación significativa de las capacidades del controlador competitivo propuesto, se ha seleccionado una planta de generación undimotriz, como escenario más desfavorable, ya que el controlador debe asegurar un control estable de la potencia inyectada en un escenario altamente oscilante. Con el fin de caracterizar adecuadamente el perfil de recursos de energía de las olas resultante de la máxima absorción de energía, esta Tesis introduce un nuevo controlador de vector adaptativo, que maximiza la extracción de energía del recurso independientemente de las características dominantes de frecuencia de onda irregular. Para la aplicación de la planta de energía de onda específica considerada, el control competitivo no solo garantiza la asignación óptima de recursos en tiempo real para satisfacer un objetivo de producción dado, sino que también proporciona una operación óptima del sistema a largo plazo. Como resultado, se pueden lograr reducciones generales de los costos de la planta en el marco de la operación competitiva, ya que la energía programada de la planta se satisface haciendo uso de las unidad
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Navarrete, Pablo-Romero Javier. "Power Quality for Distributed Wind Power Generation". Thesis, KTH, Elektroteknisk teori och konstruktion, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-105221.
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Wind power often is a source of voltage fluctuations and possible voltage issues are raised when considering interconnecting wind turbines to an electric grid. Also, the power electronics introduced in the wind turbines might insert more fluctuations and different PQ problems. Distributed generation seems to be a good option in order to try to mitigate these problems. The first goal of the work is to create a model of a small electric grid, using MATLAB/Simulink. The models aims to simulate various DFIG wind turbines coupled to the grid in different conditions of location and wind. Then, the main objective is to analyze the PQ in the grid with this type of turbine. For this, once the simulations have been done, the results obtained have allowed calculating different indices to study PQ in the model. Afterwards, a comparison of those indices in the different conditions is made.StandUp
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Forestiere, Giuseppe. "Ultra-low power circuits for power management". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-143812.
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Recent developments in energy harvesting techniques allowed implementation of completely autonomous biosensor nodes. However, an energy harvesting device generally demands a customized power management unit (PMU) in order to provide the adequate voltage supply for the biosensor. One of the key blocks within this PMU is a regulation DC-DC converter. In this Master Thesis, the most relevant switched-capacitor DC-DC converter topologies that are suitable for biosensors are compared. The topology that can achieve the best efficiency and has the minimum area is chosen and designed. In order to maintain the supply voltage of the biosensor constant when the input voltage and the output current vary, a traditional Pulse-Frequency-Modulation (PFM) control is employed. An ultra-low-power PFM control circuit is designed to operate in weak inversion region. The post-layout simulations show that the designed DC-DC converter can provide an output voltage of 900mV when the output current varies between 5μA and 40μA. Additionally, the post layout simulations of the entire system, which includes the DC-DC converter and PFM control, show that the selected topology can achieve 87% peak efficiency, when the control losses are included. The main advantages of the proposed topology are its smaller chip area and its high efficiency during processing ultra-low power levels.
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Morales, Ana. "Impact of decentralized power on power systems". Doctoral thesis, Universite Libre de Bruxelles, 2006. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210841.
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Wind generation is one of the most successful sources of renewable energy for the production of electrical energy. Wind power offers relatively high capacities, with generation costs that are becoming competitive with conventional energy sources. However, a major problem to its effective use as a power source is the fact that it is both intermittent and diffuse as wind speed is highly variable and site-specific. This is translated in large voltage and frequency excursions and dynamically unstable situations when fast wind power changes. Very high wind speeds will result in sudden loss of wind generator production. The requirement to ensure that sufficient spinning reserve capacity exists within the system to compensate for sudden loss of generation becomes crucial. From the utilities operators’point of view, the primary objective is the security of the system, followed by the quality of the supplied power.In order to guard the system security and quality of supply and retain acceptable levels, a maximum allowed wind power penetration (wind margin) is normally assumed by the operators. Very conservative methods are used to assess the impact of wind power and the consequences turn to under-exploitation of the wind power potential in a given region. This thesis presents the study of actual methods of wind power assessment, divided into three parts:
1. Part I: Impact on the Security of Power Systems
2. Part II: Impact on the Power Quality
3. Part III: Impact on the Dynamic Security of Power Systems
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
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Fadda, Mario. "Aspects of power domains and power locales". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=24001.
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Several equivalent approaches to power domains are presented: the naturality of this concept for denotational semantics is stressed and its modal interpretation is explained. We show how to solve equations involving power domains and apply the theory to an equation that leads to a characterization of bisimulations. Power locales are introduced, as the analogue of both power domains and power spaces. We study the monads defined by the power locales, their algebras and the points of the power locales.
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Suwanapingkarl, Pasist. "Power quality analysis of future power networks". Thesis, Northumbria University, 2012. http://nrl.northumbria.ac.uk/12625/.
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Pesoti, Paulo Murinelli. "Power system restorations assisted by wind power". Thesis, University of Strathclyde, 2018. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=30465.
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This thesis investigates power systems restoration procedure and the possibility of using wind power to assist restorations. Three main factors motivate this approach: the sharp growth on wind power production during recent years, the absence of wind power on restoration procedures, and recent blackouts cases which stability issues delayed the restoration procedure. Stability studies are the base of this investigation, where a series of tools are proposed and developed due to the disparate condition of a restoration procedure. The first tool is a power flow routine, where stochastic simulations address wind speed's randomness. This computational program calculates indexes of collapse for voltage stability. This computational routine also encompasses a methodology built from an energy function tool for visualizing power systems' vulnerable and robust areas. This thesis applies the tool for restoration analysis, where its validation has been published on an academic journal. This thesis also proposes a novel methodology for visualizing the robustness areas, which uses the energy function output to form a graphical representation as the system diagram's background. This thesis designs procedures and controllers for the dynamic simulation analysis. The first is the definition of a procedure used to simulate the synchronization of wind farms during restorations. This procedure aims to mitigate impacts caused by wind farms on power systems, where two loop controls achieve the desired response. Finally, one can find an initialization procedure for wind turbines, regarding restoration conditions. The robustness areas tool validation shows that one can achieve positive results on angular stability by reinforcing vulnerable areas. The guidelines proposed by the robustness areas tool test the Brazilian system operator's restoration procedure. A number of analysis and simulations assess the proposed approach efficiency. The IEEE 30 bus system, which is a benchmark for stability studies, shows the impact of wind power on restorations. Part of the Brazilian power system addresses the proposed methodology on a real case scenario. Finally, this thesis presents a list of recommendations, which intends to guide future works to include wind power on restorations and to extend the proposed approach to other power systems.
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Dancy, Abram P. (Abram Paul). "Power supplies for ultra low power applications". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10069.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (p. 101-103).
by Abram P. Dancy.
M.Eng.
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Sun, Yuhao. "Power optimised narrowband power-line communication systems". Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648110.
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Snyder, Rebecca. "The Power of Architecture: Architecture of Power". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397477684.
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Solhall, Axel, i Edvin Guéry. "Coordination of Wind Power and Hydro Power". Thesis, KTH, Industriell ekologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210740.
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The goal of this project was to calculate how much wind power could be balanced with hydro power in our designated area consisting of five hydro power stations, four villages which consume power, possible locations for wind power and one connection to the national grid. To achieve this a simulation model was constructed in the GAMS software with the goal of achieving the maximum profit from the hydro power plants by considering electricity prices, inflow of water, the physical construction of the power plants and the time of year. When this was achieved, restriction for the maximum transmission load on the power grid was added as well as local wind power production as to simulate the implementation of new power sources on an old system and power grid. This would result in a maximum income in SEK as well as the most wind power which could be maintained and balanced by the designated system. This project shows how to find the optimal way to use hydro power and wind power as well as how the integration between different sources of electricity production could work, which is vital for a future powered by renewable energy and will help towards lowering emissions.
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Eireiner, Matthias. "Power supply integrity in low power designs". Aachen Shaker, 2009. http://d-nb.info/99845642X/04.
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PIUMATTI, DAVIDE. "Reliability in Power Electronics and Power Systems". Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2918006.
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Ülker, Muhammed Akif. "Balancing of Wind Power : Optimization of power systems which include wind power systems". Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1335.
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In the future, renewable energy share, especially wind power share, in electricity generation is expected to increase. Due to nature of the wind, wind power generation pattern includes uncertainties which affects the energy prices in the electricity markets. New simulations are needed for efficient planning process for the resources in the power systems to address the uncertainties in demand, generation, legal, economical and technical limitations. In this study, the aspects of planning process for wind power generation is described and some example scenarios are implemented with the help of MATLAB software.
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Fan, Philex Ming-Yan. "Power management and power conditioning integrated circuits for near-field wireless power transfer". Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/290143.
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Near-field wireless power transfer (WPT) technology facilitates the energy autonomy of heterogeneous systems, significantly augmenting complementary metal-oxide-semiconductor field-effect-transistor (CMOS) technology. In low-power wearable devices, existing power conditioning integrated circuits do not maximize the power factor (PF) for rectification and power conversion efficiency (PCE) due to multiple conversion. Additionally, there is no core power management for the entire power flow. The majority of the research focuses on active rectifiers, which reduce the turn-on voltage for rectification. Certain studies target the output voltage regulation via feedback to the transmitter or direct battery charging without power maximization. Firstly, this study investigates a high-power factor WPT front-end circuit that is namely the mono-periodic switching rectifier (MPSR) and implemented in a 0.18µm 1.8V/5V CMOS process. Integrated phase synchronizers are used to align the waveshape of a wirelessly-coupled sinusoidal voltage source in a receiving coil to the corresponding conducting current. Using this approach, the PF can be increased from roughly 0.6 to unity without requiring any wireless or wired feedback to the transmitter. The proposed MPSR can also provide AC-DC rectification, and step up and down the sinusoidal voltage source's peak amplitude using a pulse-width modulator. Measured voltage conversion ratios range between 0.73X and 2X, and the PF can be boosted up to unity. Secondly, the wireless power system-on-chip (WPower-SoC) is proposed and implemented in a 0.18µm 1.8V/3.3V CMOS process. The WPower-SoC integrating power management can provide rectification, output voltage regulation, and battery charging. Additionally, the implementation of feedforward envelope detection (FED) can reduce the variation in a wireless power link and improve load transient responses. Simulated results demonstrate that 5% of the output voltage regulation is improved when an output load changes. Moreover, the FED reduces approximately 40% of the transient response time. Overshoot and undershoot voltages are decreased by 23% and 26.5%, respectively. The measured output voltage regulates at 3.42V and can supply output power up to 342mW. A temperature sensor as part of the power management core remains active when the WPT receivers enter sleep mode to prolong the battery usage time. In the final part of this study, a nano-watt high-accuracy temperature sensing core is implemented in a 0.18µm 1.8V/3.3V CMOS process that can self-compensate the temperature shift without the need for additional compensating techniques that consume extra power.
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Granlund, Robert. "Russan Power Projection and Power Ministries : A Study in Russian Power Ministry Influence". Thesis, Försvarshögskolan, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-3975.
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Severino, Krisvanbaelen Alexandra dos Santos. "A importância do poder na criação do GATT : a influência do poder estatal nas negociações do acordo". Master's thesis, Instituto Superior de Economia e Gestão, 2012. http://hdl.handle.net/10400.5/4995.
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Mestrado em Desenvolvimento e Cooperação InternacionalRESUMO: O GATT 1947 foi um acordo de redução tarifária celebrado por 23 países em Genebra. A forma como o poder estatal influenciou a sua forma pode ser observada através do processo de negociações que levaram ao acordo. O processo de negociações foi logo condicionado pelo poder na medida em que os EUA, a maior potência ocidental, iniciou negociações com o Reino Unido. O interesse de ambos os países determinou quem podia participar das negociações de Genebra. Mostrando isso como os actores mais poderosos estabeleceram os parâmetros da negociação do acordo. O poder também pode ser observado efectivamente nas negociações de Genebra através do “bargaining power” dos diferentes países e a capacidade que eles tiveram de representar os seus interesses no acordo. Porém, também aqui os EUA assumiram centralidade na medida em que os outros negociaram tendo como referência os seus interesses.
The GATT 1947 was an agreement for tariff reductions celebrated between 23 countries in Geneva. The way that state power affected its design can be observed through the negotiation process that led to the agreement. The negotiation process was conditioned by power right away in the sense that the United States, the biggest power in the western world, initiated negotiations with the United Kingdom. The interest of both these countries (and the countries of interest to them) determined who could participate in the Geneva negotiations. This shows how the most powerful actors established the parameters of the negotiation of the agreement. Power can also be observed effectively in the Geneva negotiations by the bargaining power of the different countries and how they were able to represent their interests in the agreement. However, in this too the US took center stage in the sense that the others bargained in reference to this country’s interests.
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Cable, Kasey Elizabeth. "The War Powers Resolution: Reassessing the Constitutional Balance of Power". DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/224.
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This thesis is an analysis of the War Powers Resolution of 1973 and the impact it held on the role of Congress and the President in entering war. More specifically, this thesis takes a look at President Richard M. Nixon’s influence on the 93rd Congress’s decision to pass the War Powers Resolution after multiple failed attempts at similar legislation. Through a major domestic policy blunder, the Watergate break-in, and a foreign policy disaster, the on-going war in Vietnam, opposition to Nixon’s presidential conduct united both the House and the Senate and resulted in legislation that would attempt to restore the Constitutional balance of power.
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Li, Yiyang. "Novel power converter topologies to interface solar power to power grid with battery backup". Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/23269.
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The main aim of this thesis is to develop a solar energy system for domestic utilities, using a bi-directional DC-DC boost converter with a battery storage system in it. Topologies of the converters employed in the existing system are not efficient, especially in high power applications because of complicated structures with many power devices. In order to step up the DC voltage of the solar panel to a value suitable for AC power conversion, the DC-DC converter topologies has used either multiple stages of voltage amplification or complicated structures with many power devices as the voltage gain offered by the standard boost converter is not adequate enough. This has led to the use of complicated switching control methods. As a result of such power converters with low power density, the cost of the system is also high with relatively low efficiency. The above-mentioned shortcomings have led researchers to investigate new topologies of converters and efficient control methods. The thesis investigates the existing topologies of DC-DC boost converters pointing out advantages and disadvantages and presents ten new topologies that are superior to existing ones. Detailed analysis of converters is presented, and the mathematical model is developed to determine the voltage gain as a function of duty cycle. The presented converter topologies are also designed, and prototypes fabricated in the laboratory. The fabricated converters are tested experimentally using Arduino micro-controller. Programs are developed to control the converters in different modes of operation and the performance curves are generated. The experimental results support the theoretical model developed and the obtained results are presented in the thesis. A bi-directional DC-AC converter topology is also developed to interface the solar panel to the AC grid. The developed topology makes use of one of the DC-DC converter topologies presented and offers battery backup facility in it. This system can be controlled to store power either from AC grid or from the solar panel and can power the AC load or inject power to the grid. Appropriate control methods are developed for the bi-directional converter system and extensive simulation studies are conducted using MATLAB/Simulink to demonstrate the operation of the system in different modes of operation and simulation results are also presented. The converter system has also been fabricated and tested with solar panels. The test results of different modes of operation are also presented. Finally, the authors’ viewpoint in the development of power electronics in solar application is presented.
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Yu, Jung-Min. "Political economy of power liberalization and power transformation". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 270 p, 2010. http://proquest.umi.com/pqdweb?did=1997524051&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Thesis (Ph.D.)--University of Delaware, 2009.Principal faculty advisors: Young-Doo Wang, School of Urban Affairs & Public Policy; and John Byrne, Center for Energy and Environmental Policy. Includes bibliographical references.
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Lyon, Robert Allen. "Prime power for shipboard high-average power FELs". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA293718.
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Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering) Naval Postgraduate School, December 1994.Thesis advisor(s): Robert W. Ashton, Robert L. Armstead, W.B. Colson. "December 1994." Includes bibliographical references. Also available online.
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Montenegro, León Alejandro. "Advanced power electronic for wind-power generation buffering". [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010112.
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Yousefzadeh, Vahid. "Digitally controlled power converters for RF power amplifiers". Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219220.
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Cvetkovic, Milos. "Power-Electronics-Enabled Transient Stabilization of Power Systems". Research Showcase @ CMU, 2013. http://repository.cmu.edu/dissertations/344.
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Transient stability of electric energy grids is defined as the ability of the power system to remain in synchronism during large disturbances. If the grid is not equipped with controllers capable of transiently stabilizing system dynamics, large disturbances could cause protection to trigger disconnecting the equipment and leading further to cascading system-wide blackouts. Today’s practice of tuning controllers generally does not guarantee a transiently stable response because it does not use a model for representing system-wide dynamic interactions. To overcome this problem, in this thesis we propose a new systems modeling and control design for provable transient stabilization of power systems against a given set of disturbances. Of particular interest are fast power-electronically-controlled Flexible Alternating Current Transmission System (FACTS) devices which have become a new major option for achieving transient stabilization. The first major contribution of this thesis is a framework for modeling of general interconnected power systems for very fast transient stabilization using FACTS devices. We recognize that a dynamic model for transient stabilization of power systems has to capture fast electromagnetic dynamics of the transmission grid and FACTS, in addition to the commonly-modeled generator dynamics. To meet this need, a nonlinear dynamic model of general interconnected electric power systems is derived using time-varying phasors associated with states of all dynamic components. The second major contribution of this thesis is a two-level approach to modeling and control which exploits the unique network structure and enables preserving only relevant dynamics in the nonlinear system model. This approach is fundamentally based on separating: a) internal dynamics model for ensuring stable local response of components; b) system-level model in terms of interaction variables for ensuring stability of the system when the components are interconnected. The two levels can be controlled separately which minimizes the need for communication between controllers. Both distributed and cooperative ectropy-based controllers are proposed to control the interaction-level of system dynamics. Proof of concept simulations are presented to illustrate and compare the promising performance of the derived controllers. Some of the most advanced FACTS industry installations are modeled and further generalized using our approach.
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El-Damak, Dina Reda. "Power management circuits for ultra-low power systems". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99821.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 137-145).
Power management circuits perform a wide range of vital tasks for electronic systems including DC-DC conversion, energy harvesting, battery charging and protection as well as dynamic voltage scaling. The impact of the efficiency of the power management circuits is highly profound for ultra-low power systems such as implantable, ingestible or wearable devices. Typically the size of the system for such applications does not allow the integration of a large energy storage device. Therefore, extreme energy efficiency of the power management circuits is critical for extended operation time. In addition, flexibility and small form factor are desirable to conform to the human body and reduce the system's over all size. Thus, this thesis presents highly efficient and miniature power converters for multiple applications using architecture and circuit level optimization as well as emerging technologies. The first part presents a power management IC (PMIC) featuring an integrated reconfigurable switched capacitor DC-DC converter using on-chip ferroelectric caps in 130 nm CMOS process. Digital pulse frequency modulation and gain selection circuits allow for efficient output voltage regulation. The converter utilizes four gain settings (1, 2/3, 1/2, 1/3) to support an output voltage of 0.4 V to 1.1 V from 1.5 V input while delivering load current of 20 [mu]A to 1 mA. The PMIC occupies 0.366 mm² and achieves a peak efficiency of 93% including the control circuit overhead at a load current of 500 [mu]A. The second part presents a solar energy harvesting system with 3.2 nW overall quiescent power. The chip integrates self-startup, battery management, supplies 1 V regulated rail with a single inductor and supports power range of 10 nW to 1 [mu]W. The control circuit is designed in an asynchronous fashion that scales the effective switching frequency of the converter with the level of the power transferred. The ontime of the converter switches adapts dynamically to the input and output voltages for peak-current control and zero-current switching. The system has been implemented in 180 nm CMOS process. For input power of 500 nW, the proposed system achieves an efficiency of 82%, including the control circuit overhead, while charging a battery at 3 V from 0.5 V input. The third part focuses on developing an energy harvesting system for an ingestible device using gastric acid. An integrated switched capacitor DC-DC converter is designed to efficiently power sensors and RF transmitter with a 2.5 V regulated voltage rail. A reconfigurable Dickson topology with four gain settings (3, 4, 6, 10) is used to support a wide input voltage range from 0.3 V to 1.1 V. The converter is designed in 65 nm CMOS process and achieves a peak efficiency of 80% in simulation for output power of 2 [mu]W. The last part focuses on flexible circuit design using Molybdenum Disulfide (MoS₂), one of the emerging 2D materials. A computer-aided design flow is developed for MoS₂-based circuits supporting device modeling, circuit simulation and parametric cell-based layout - which paves the road for the realization of large-scale flexible MoS₂ systems.
by Dina Reda El-Damak.
Ph. D.
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Al-Anfaji, Ahmed Suaal Bashar. "The optimization of combined power-power generation cycles". Thesis, University of Hertfordshire, 2015. http://hdl.handle.net/2299/15485.
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An investigation into the performance of several combined gas-steam power generating plants’ cycles was undertaken at the School of Engineering and Technology at the University of Hertfordshire and it is predominantly analytical in nature. The investigation covered in principle the aspect of the fundamentals and the performance parameters of the following cycles: gas turbine, steam turbine, ammonia-water, partial oxidation and the absorption chiller. Complete thermal analysis of the individual cycles was undertaken initially. Subsequently, these were linked to generate a comprehensive computer model which was employed to predict the performance and characteristics of the optimized combination. The developed model was run using various input parameters to test the performance of the cycle’s combination with respect to the combined cycle’s efficiency, power output, specific fuel consumption and the temperature of the stack gases. In addition, the impact of the optimized cycles on the generation of CO2 and NOX was also investigated. This research goes over the thermal power stations of which most of the world electrical energy is currently generated by. Through which, to meet the increase in the electricity consumption and the environmental pollution associated with its production as well as the limitation of the natural hydrocarbon resources necessitated. By making use of the progressive increase of high temperature gases in recent decades, the advent of high temperature material and the use of large compression ratios and generating electricity from high temperature of gas turbine discharge, which is otherwise lost to the environment, a better electrical power is generated by such plant, which depends on a variety of influencing factors. This thesis deals with an investigation undertaken to optimize the performance of the combined Brayton-Rankine power cycles' performance. This work includes a comprehensive review of the previous work reported in the literature on the combined cycles is presented. An evaluation of the performance of combined cycle power plant and its enhancements is detailed to provide: A full understanding of the operational behaviour of the combined power plants, and demonstration of the relevance between power generations and environmental impact. A basic analytical model was constructed for the combined gas (Brayton) and the steam (Rankine) and used in a parametric study to reveal the optimization parameters, and its results were discussed. The role of the parameters of each cycle on the overall performance of the combined power cycle is revealed by assessing the effect of the operating parameters in each individual cycle on the performance of the CCPP. P impacts on the environment were assessed through changes in the fuel consumption and the temperature of stack gases. A comprehensive and detailed analytical model was created for the operation of hypothetical combined cycle power and power plant. Details of the operation of each component in the cycle was modelled and integrated in the overall all combined cycle/plant operation. The cycle/plant simulation and matching as well as the modelling results and their analysis were presented. Two advanced configurations of gas turbine cycle for the combined cycle power plants are selected, investigated, modelled and optimized as a part of combined cycle power plant. Both configurations work on fuel rich combustion, therefore, the combustor model for rich fuel atmosphere was established. Additionally, models were created for the other components of the turbine which work on the same gases. Another model was created for the components of two configurations of ammonia water mixture (kalina) cycle. As integrated to the combined cycle power plant, the optimization strategy considered for these configurations is for them to be powered by the exhaust gases from either the gas turbine or the gases leaving the Rankine boiler (HRSG). This included ChGT regarding its performance and its environmental characteristics. The previously considered combined configuration is integrated by as single and double effect configurations of an ammonia water absorption cooling system (AWACS) for compressor inlet air cooling. Both were investigated and designed for optimizing the triple combination power cycle described above. During this research, tens of functions were constructed using VBA to look up tables linked to either estimating fluids' thermodynamic properties, or to determine a number of parameters regarding the performance of several components. New and very interesting results were obtained, which show the impact of the input parameters of the individual cycles on the performance parameters of a certain combined plant’s cycle. The optimized parameters are of a great practical influence on the application and running condition of the real combined plants. Such influence manifested itself in higher rate of heat recovery, higher combined plant thermal efficiency from those of the individual plants, less harmful emission, better fuel economy and higher power output. Lastly, it could be claimed that various concluding remarks drawn from the current study could help to improve the understanding of the behaviour of the combined cycle and help power plant designers to reduce the time, effort and cost of prototyping.
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Shams, Solary Arasto. "Wind power plants integration to the power grid". Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-200633.
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Amarasinghe, Kanishka A. "Resonance mode power supplies with power factor correction". Thesis, Loughborough University, 1990. https://dspace.lboro.ac.uk/2134/23672.
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There is an increasing need for AC-DC converters to draw a pure sinusoidal current at near unity power factor from the AC mains. Most conventional power factor correcting systems employ PWM techniques to overcome the poor power factor being presented to the mains. However, the need for smaller and lighter power processing equipment has motivated the use of higher internal conversion frequencies in the past. In this context, resonant converters are becoming a viable alternative to the conventional PWM controlled power supplies. The thesis presents the implementation of active power factor correction in power supplies, using resonance mode techniques. It reviews the PWM power factor correction circuit topologies previously used. The possibility of converting these PWM topologies to resonant mode versions is discussed with a critical assessment as to the suitability of the semiconductor switching devices available today for deployment in these resonant mode supplies. The thesis also provides an overview of the methods used to model active semiconductor devices. The computer modelling is done using the PSpice microcomputer simulation program. The modifications that are needed to the built in MOSFET model in PSpice, when modeling high frequency circuits is discussed. A new two transistor model which replicates the action of a OTO thyristor is also presented. The new model enables the designer to estimate the device parameters with ease by adopting a short calculation and graphical design procedure, based on the manufacturer's data sheets. The need for a converter with a high efficiency, larger power/weight ratio, high input power factor with reduced line current distortion and reduced cost has led to the development of a new resonant mode converter topology, for power processing. The converter presents a near resistive load to the mains thus ensuring a high input power factor, while providing a stabilised de voltage at the output with a small lOOHz ripple. The supply is therefore ideal for preregulation applications. A description of the modes of operation and the analysis of the power circuit are included in the thesis. The possibility of using the converter for low output voltage applications is also discussed. The design of a 300W, 80kHz prototype model of this circuit is presented in the thesis. The design of the isolation transformer and other magnetic components are described in detail. The selection of circuit components and the design and implementation of the variable frequency control loop are also discussed. An evaluation of the experimental and computer simulated results obtained from the prototype model are included in the presentation. The thesis further presents a zero-current switching quasi-resonant flyback circuit topology with power factor correction. The reasons for using this topology for off-line power conversion applications are discussed. The use of a cascoded combination of a bipolar power transistor and two power MOSFETs i~ the configuration has enabled the circuit to process moderate levels of power while simultaneously switching at high frequencies. This fulfils the fundamental precondition for miniaturisation. It also provides a well regulated DC output voltage with a very small ripple while maintaining a high input power factor. The circuit is therefore ideal for use in mobile applications. A preliminary design of the above circuit, its analysis using PSpice, the design of the control circuit, current limiting and overcurrent protection circuitry and the implementation of closed-loop control are all included in the thesis. The experimental results obtained from a bread board model is also presented with an evaluation of the circuit performance. The power factor correction circuit is finally installed in this supply and the overall converter performance is assessed.
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Arana, Andrew Jex. "Power Systems Analysis in the Power-Angle Domain". Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/30001.
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The idea of performing power systems dynamic analysis in the power-angle domain has been hinted at by previous researchers, but this may be the first published document to develop detailed techniques by which entire power systems can be represented and solved in the power-angle domain. With the widespread deployment of phasor measurement units and frequency data recorders the industry is looking for more real-time analytical tools to turn real-time wide-area measurements into useful information. Applications based on power-angle domain analysis are simple enough that they may be used online.
Power-angle domain analysis is similar to DC load-flow techniques in that a flat voltage profile is used and it is assumed that real power and voltage angle are completely decoupled from reactive power and voltage magnitude. The linearized equations for the dynamics of generators and loads are included in the model, which allows the electromechanical response to be solved using conventional circuit analysis techniques. The effect of generation trips, load switching, and line switching can be quickly approximated with nodal analysis or mesh analysis in the power-angle domain.
The analysis techniques developed here are not intended to be as accurate as time-domain simulation, but they are simpler and fast enough to be put online, and they also provide a better analytical insight into the system. Power-angle domain analysis enables applications that are not readily available with conventional techniques, such as the estimation of electromechanical propagation delays based on system parameters, the formulation of electromechanical equivalents, modal analysis, stability analysis, and event location and identification based on a small number of angle or frequency measurements. Fault studies and contingency analysis are typically performed with detailed time-domain simulations, where the electromechanical
response of the system is a function of every machine in the interconnection and the lines connecting them. All of this information is rarely known for the entire system for each operating condition; as a result, for many applications it may be more suitable to compute an approximation of the system response based on the current operating state of only the major lines and generators. Power-angle domain analysis is adept at performing such approximations.Ph. D.
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Nilsmo, Oscar, i Ludwig Abrahamsson. "A comparison of wind power and nuclear power". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232559.
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År 2019 och 2020 kommer kärnreaktorerna Ringhals 1 och 2 läggas ner. I Denna rapporten undersöks hur många vindkraftverk som behöver byggas för att ersätta och kompensera för den årliga elproduktionen från reaktorerna i Ringhals. Därefter undersöks; vilka geografiska riksintressen som finns för byggnation av dessa vindkraftverk, vad som avgör om ett område är intressant, åtgång av markyta, skövling av skog, samt i vilken mån vindkraften byggs ut idag. Rapporten undersöker dessutom möjligheten att ersätta reaktorerna i Ringhals med vindkraftverk utifrån att det inte existerar någon reglerkraft som kan garantera leveranssäkerheten av el. I rapporten görs även en livscykelanalys baserat på vindkraftverkens totala koldioxidutsläpp. Livscykelanalysen jämförs med en tidigare befintlig analys från Vattenfall. Avslutningsvis görs en jämförelse mellan vindkraft och kärnkraft. I denna jämförelse undersöks och uppskattas det totala koldioxidutsläpp som reaktorerna har haft under sin livstid för att sedan jämföras med de totala utsläpp som de 1927 vindkraftverken kommer ha under en motsvarande tid. Ämnen i vindkraftverken såsom plastkemikalien bisfenol A, jordartsmetallerna neodymium och dysprosium undersöks i denna rapporten för att bestämma huruvida dessa ämnen har en negativ påverkan på miljön eller inte. För att ersätta produktionen av el, som produceras av reaktorerna i Ringhals, behövs 1927 vindkraftverk. Mellan varje vindkraftverk behövs ett avstånd av 4–10 rotordiametrar beroende på landskapsbild. Detta medför att det åtminstone behövs cirka 970 km2 av den 7886,8 km2 geografisk potentiella markytan för byggnation. Om vindkraftverken byggs i skogsområden antas 22 km2 skog behöva avverkas. I dag är antalet vindkraftverk överrepresenterade i Götaland och i Norrland. Vindkraften förväntas att i framtiden öka ännu mer i de norra delarna av Sverige. Kostnaden för produktion och drift/ underhåll av1927 vindkraftverk är cirka 42 miljarder kr. För Kärnkraft är motsvarande siffra för byggnation och demontering 76 miljarder kr. I rapportens livscykelanalys framkom att vid produktion av material, transport och deponering av ett vindkraftverk produceras totalt 500 ton CO2. Detta medför att 1927 vindkraftverk har en total CO2 påverkan av 936,5 tusen ton. De två reaktorerna i Ringhals har ett totalt utsläpp på 2,5 miljoner ton CO2 under sin livstid.In 2019 and 2020, the nuclear reactors Ringhals 1 and 2 will be taken out of production. This report aims to investigate the required number of wind power plants that have to be constructed to equate the annual production of electricity of the Ringhals reactors. Subsequently, the report evaluates national considerations in connection to the required construction of wind power stations regarding the use of land, necessary deforesting, the existing use of wind power stations in Sweden and the cost and carbon dioxide emissions of producing new wind power stations to compensate for the removal of Ringhals 1 and 2. To replace the production of electricity from Ringhals 1 and 2, 1,927 wind power stations with a distance of 4-10 rotor diameters depending on the geographical position, necessitating a minimum area of 970 km2 designated for wind powered electricity production. The cost for production and maintenance of the 1,927 wind power stations is estimated to 42 billion SEK. In a life cycle analysis of the total carbon emissions, the transport of material and subsequent production, maintenance and demolition of 1,927 wind power stations is estimated to produce a total of 936,500 metric tonnes of carbon dioxide and the corresponding amount for the production of Ringhals is estimated to 2,500,000 metric tonnes.
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Beikoff, Geoffrey Noel. "A high power, high voltage switching power supply". Thesis, Queensland University of Technology, 1992. https://eprints.qut.edu.au/36226/1/36226_Beikoff_1992.pdf.
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A switching power supply to drive magnetrons for microwave heating has
been designed, prototyped and tested. The magnetron has an rf power
output of 6000 watts and requires a DC voltage of 7200 volts at a current
of approximately 1.1 amps for a power input to the magnetron of 8000
watts. Six magnetrons are to be connected per railway tanker for heating
the tankers at a railway terminus.
The power supply has been designed for small size, efficiency and
reliability. Current technology has been used. Insulated Gate Bipolar
Transistors (IGBT) and power MOSFETs, both of moderately high current
and voltage ratings, have been used at 25 kHz and 50 kHz switching
frequencies respectively. MOSFETs of 20 amps and 500 volts and IGBT's
of 40 amps and 600 volts ratings have been used. Ferrites for use at high
switching frequencies have been used for transformers and iron powder
material has been used for energy storage inductors. High quality
insulating materials have been used to achieve the high voltage insulation
requirements. Kapton, PTFE, mylar and nylon have been used where
appropriate.
Special features of the power supply include the power factor correction
first stage, the use of the higher than normal leakage inductance of the
power converter second stage transformer to make a resonant converter
and the ripple cancelling effect of the series connection of the units on
each phase. The power factor correction meets I EC 555 and AS2279
standards for harmonic content on the power supply source. The resonant
converter yields zero load current switching of the converter transistors.
The output 100 Hz ripple on the 7200 volt supply is negligible because of
the series connection of the three outputs.
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Makhalas, Kharsan Al, i Faisal Alsehlli. "Wind Power". Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4336.
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This Bachelor thesis has been written at the Blekinge Institute of Technology. This thesis concentrates on the wind power and their components, also the large wind farm is studied. The electrical power is generated by using the power in wind to drive a wind turbine to produce mechanical power. This mechanical power can be converted into electrical power by using electrical induction generators. There are two types of the wind turbines, the horizontal axis and vertical axis wind turbine, where the horizontal axis wind turbine is mostly used and was studied in this thesis. The rotor can be placed in two directions: an upwind rotor where the blade of turbine faces to the wind, so it operates more smoothly and transmit more power. The other type is a downwind rotor which orients itself with respect for the wind direction. Moreover, the tower shadow makes the blade to flex, consequently resulting in fatigue, noise, and reduces output of the power. The modern wind turbine has been built with an odd number of blades which is important for the stability of the turbine. The rotor with an odd number of blades can be considered to be similar to a disc when calculating the dynamic properties of the machine. The main idea of this thesis is to study the wind power in general and large wind parks specifically. The Horns Rev wind park was taken as an example of a wind park in Denmark and the Gotland wind park as an example of a wind park in Sweden too. Into account, the distance between wind turbine in the wind direction cannot be too small. If the wind turbines are located to close to each other, the wind will be more and more turbulent after it passes through each single wind turbine. This would lead to that wind turbines downstream in the wind park, and it might even have to shut down due to that mechanical loading gets to high during strong conditions. This is due to the fact that when wind passes through the rotor of the wind turbine it gets very turbulent and the wind speed is decreased. The minimum length of the rotor should be approximately 5-7 rotor diameters to avoid that issue. Gotland Energy AB (GEAB) considered, that high voltage direct current light would be the only realistic way to solve the technical problems for the high amount of wind power in-feed. One result is that The stability of voltage during transient events, has become much better by using the high voltage direct current light so that the output current stability from the asynchronous generators have been improved, which reduces the stresses on the AC grid and on the mechanical construction of the windmills.In general the wind turbines with three blades accommodated a thicker root are used. It is obvious that, the less number of blades on the wind turbine, the cost of material and manufacturing will be lower. It is worthy to mentioned that, the modern wind turbine has been built with an odd number of blades. When the length of the blade increases the deflection of blade tip due to axial wind force also increase as well. So without consider the increase in length of blade may lead to dangerous situation of collision of tower and blade. Moreover, by increasing the number of blades cost of the system would increased as well. The limit of transfer for the AC transmission system depends on the distance from shore and is therefore physically limited by this. AC large wind parks that are placed at a long distance from the shore, which means AC long transmission line, and more drop voltage A solution to AC long transmission line, it could be to decrease the offshore frequency and use a low frequency AC networks. There is a suggestion by for instance (Schütte, Gustavsson and Ström 2011). The usages of a low frequency system are in electrified railway systems, where the frequency ranges from 16.67 Hz to 25 Hz. However, the network of a low frequency would allow a simpler design of the offshore WTs and The aerodynamic rotor of a large WT operates at maximum revolutions at 15-20 rpm. The lower frequency would then allow a smaller gear ratio for turbines with a gearbox, or decrease the poles number for WTs with direct driven generators. This would lead to lighter and cheaper turbines. One of the disadvantages by using a low frequency system is the size of transformer would be increased, and hence, the costs of transformer will increased too. The operator of the grid, Gotland Energy AB (GEAB) considered, that HVDC light would be the only realistic way to solve the technical problems for the high amount of wind power in-feed. The experiences have supported expected improvements in the characteristics for example: - Stability in the system arose. - Reactive demands, power flows, as well as voltage level in the harmonic and system were reduced. - Flicker problems were eliminated with the installation of HVDC light and transient phenomena disappeared. Moreover, Overall experiences of Gotland Energy AB (GEAB) are that the control of power flow from the converters makes the AC grid easier to observe than a conventional AC network and the power variations do not stress the AC grid as much as in normal network. Voltage quality has been better with the increased wind power production. A topic to study in the future is the consequences of blackouts in power supply with many wind power farm.
004676396018
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Bernardo, Espinoza Patricia, Mogollon Gisella Lucero Cepeda, Huanaco Claudia Paola Pacasi, Muñoz Flor Maximina Rojas i Limachi Everardo Tacca. "Quinua Power". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2021. http://hdl.handle.net/10757/655540.
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Quinua Power ha sido creado con el fin de brindar una nueva propuesta de consumo de cereales a todas aquellas personas que buscan cuidar su alimentación y a los que combaten alguna enfermedad alimenticia que les impida desarrollar su crecimiento o desenvolvimiento en el ámbito estudiantil.
Este producto consiste en la elaboración de cereales en base a la quinua. Este es considerado como un grano andino esencial en la alimentación de toda persona, debido a sus propiedades nutricionales. En la región, el Perú y Bolivia son los principales productores de este grano y cada año se establecen metas de consumo nacional, en busca de fortalecer la salud nutricional de las personas, pero en especial de sus niños.
Las operaciones de producción y venta se iniciarán en Lima Metropolitana. Este producto está dirigido a hombres, mujeres y niños que se encuentren entre los 15 a 35 años de edad y pertenezcan a los niveles socioeconómicos C y D, quienes, en la actualidad, presentan mayor crecimiento de consumo de este tipo de productos.
Este proyecto tendrá una duración de 3 años; para iniciar las operaciones será necesario invertir S/23,585.00, de los cuales el 80% será aporte de los accionistas y el 20% será financiado a través de un inversionista ángel. Entre los indicaros obtenidos para este proyecto, se tiene un costo promedio ponderado de capital de 16.67%, VAN de S/19,884 que indica que en el plazo de 3 años se recupera la inversión y una TIR de 60.90% que indica que el proyecto es rentable.
Finalmente, con estos indicadores podemos confirmar que el proyecto es viable pues tiene un adecuado tiempo de recuperación y altos índices de rentabilidadQuinoa Power has been created with the purpose of providing a new option for consuming cereals to all those who seek to take care of their diet and to those who fight any nutritional disease that prevents them from developing their growth or development in the student environment. This product consists of the production of cereals based on quinoa. This is considered an essential Andean grain in the diet of everyone, due to its nutritional properties. In the region, Peru and Bolivia are the main producers of this grain and each year national consumption goals are established, seeking to strengthen the nutritional health of people, but especially of their children. Production and sale operations will begin in Metropolitan Lima. This product is aimed at men, women and children who are between 15 and 35 years of age and belong to socioeconomic levels C and D, who, at present, show the highest growth in consumption of this type of product. This project will last for 3 years; to start operations, it will be necessary to invest S / 23,585.00; of which 80% will be a shareholder contribution and 20% will be financed through an angel investor. Among the indicators obtained for this project, there is a weighted average cost of capital of 16.67%, NPV of S / 19,884 that indicates that the investment is recovered within 3 years and an IRR of 60.90% that indicates that the project is profitable. Finally, with these indicators we can confirm that the project is viable since it has an adequate recovery time and high profitability rates.
Trabajo de investigación
43
Strokin, О. О. "Nuclear power". Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/33870.
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Nuclear power is generated using Uranium, which is a metal mined in various parts of the world. The first large-scale nuclear power station opened at Calder Hall in Cumbria, England, in 1956.Some military ships and submarines have nuclear power plants for engines. Nuclear power produces around 11% of the world's energy needs, and produces huge amounts of energy from small amounts of fuel, without the pollution that you'd get from burning fossil fuels. Nuclear power stations work in pretty much the same way as fossil fuel-burning stations, except that a "chain reaction" inside a nuclear reactor makes the heat instead.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/33870
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Золотова, Світлана Григорівна, Светлана Григорьевна Золотова, Svitlana Hryhorivna Zolotova i D. A. Mazur. "Tidal power". Thesis, Вид-во СумДУ, 2011. http://essuir.sumdu.edu.ua/handle/123456789/22050.
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Tidal power is the only form of energy which derives directly from the relative motions of the Earth–Moon system, and to a lesser extent from the Earth–Sun system. Tidal forces produced by the Moon and Sun, in combination with Earth's rotation, are responsible for the generation of the tides.
Tidal energy is extracted from the relative motion of large bodies of water. Periodic changes of water levels, and associated tidal currents, are due to the gravitational attraction of the Sun and Moon. Magnitude of the tide at a location is the result of the changing positions of the Moon and Sun relative to the Earth, the effects of Earth rotation, and the local geography of the sea floor and coastlines. Because the Earth's tides are ultimately due to gravitational interaction with the Moon and Sun and the Earth's rotation, tidal power is practically inexhaustible and classified as a renewable energy resource.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/22050
45
Saville, Marco. "Power playground". Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25425.
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Communities on the Cape Flats of the Western Cape have become synonymous with 'overcrowding, poverty, and squatters' (Pinnock, 2016: 12). Segregation under the apartheid regime forcibly placed Black and Coloured citizens in these areas. These areas have since become eclectic linguistic platforms where many languages form part of the daily liveliness. One of the registers used, is sabela. This is a register born in the prison gangs that has filtered out into the streets, and schools within the surrounding areas. This study, conducted in a school on the Cape Flats, follows the linguistic resources deployed by two Grade 9 boys, as they negotiate their way through different interactions within the informal school setting. The study is based on Linguistic Ethnography (Rampton, 2004), and draws on a view of language as a social practice (Fairclough 1989/ 2001), with particular focus on the contexts (Blommaert, 2005) that inform interactions. The important influence of different discourses in the linguistic marketplace (Bourdieu, 1977) frame the analysis of interactions, and evidence of performativity (Butler, 1990) and footing (Goffman, 1981) are seen as an important factors when investigating abilities to perform particular identities. Hence my research question is: How does sabela function within the linguistic repertoires of two boys in informal spaces at a School on the Western Cape Flats? The data collected consists of audio recordings made over the period of five days, during the two interval sessions of each day, as well as interviews conducted with research participants. The findings showed that the boys had a wide linguistic repertoire that could be strategically deployed. They drew on many different resources from their repertoires with different effects, sabela was drawn on as a signifier of power both in the informal school space and in interactions.
46
Lembke, Fritiof, i Tarek Penser. "Tidal Power". Thesis, KTH, Maskinkonstruktion (Inst.), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209541.
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Tidal power is a relatively new area within renewable energy with great potential in some areas of the world. One of the companies working with this is Minesto, and they have developed a technology called Deep Green that uses a kite that is attached to the seabed to generate electricity. The purpose of this project is to research technologies for production of electricity from tides and under water streams and also to describe the Deep Green technology, compare it to other technologies and propose some suggestions to the current solution. The study is separated into two parts and begins with a research faze on Minesto and other companies that have projects within tidal energy. The other section is a modelling faze where models that describe the Deep Greens movement are made. Forces that the system is exposed to are also calculated for further dimensioning of the components. The research revealed that Minesto has some advantages in comparison to the other companies that were looked at. The largest ones were that Deep Green can produce electricity effectively at low water speeds and that the power plants are relatively light. The Modelling showed that the wing moves closer to the seabed at higher water speeds and that some of the components in the system are over dimensioned and could be designed to be lighter.Tidvattenkraft är ett relativt nytt område inom förnybar energi med stor potential i vissa delar av världen. Ett företag som arbetar med just detta är Minesto som tagit fram en teknologi som heter Deep Green och tagit inspiration från drakflygning för att generera energi från havet. Syftet med projektet är att åt Minesto genomföra en informationssökning om konkurrerande teknologier till Deep Green, att med modeller beskriva Deep Green teknologin samt föreslå förbättringar av den nuvarande lösningen. Studien är indelad i två delar och börjar med informationssökning om Minesto och andra företag som arbetar med tidvattenkraft. Den andra delen är en modelleringsfas där modeller som beskriver Deep Greens rörelse tas fram och även krafter för vidare dimensionering av komponenter i systemet. Informationssökningen visade att Minesto har tydliga fördelar i jämförelse med de andra konkurrenter som undersökts. Framför allt att Deep Green kan producera elektricitet effektivt vid låga vattenhastigheter och att kraftverken är relativt lätta. Modelleringen visade att vingen rör sig närmre botten vid högre vattenhastigheter och att vissa komponenter i systemet är överdimensionerade och skulle kunna göras lättare.
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Vice, President Research Office of the. "Pellet Power". Office of the Vice President Research, The University of British Columbia, 2009. http://hdl.handle.net/2429/9507.
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Camere, Salcedo Renzo Fabian, Reaño Jesus Salvador Enco, Silva Adrian Gonzalez i Balarezo Adela Catherine Vassallo. "Power EGG". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626421.
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Hoy en día, el gobierno peruano establece normas de protección saludable para los niños con el fin de proteger su salud. Por ese motivo, la industria alimenticia y el consumidor peruano vienen cambiando sus hábitos de compras y consumo saludable, de cara a estos cambios, se ha detectado la oportunidad de ofrecer un producto alimenticio saludable y nutritivo contribuyendo a la salud de los niños peruanos.
“Power Eggs” busca posicionarse en el mercado peruano en los segmentos A, B y C como un complemento nutricional, brindando a las madres de familia una alternativa de nutrición para el consumo diario de los niños.
El mercado al que se apunta está conformado por 9, 485,406 de mujeres con hijos entre las edades de 2 a 12 años en la ciudad de Lima, para el cual se ha calculado un mercado target de 1,171,437 personas.
Uno de los principales objetivos es alcanzar un 20% de participación sobre el target de 39,420 personas, como un crecimiento anual de 10% en los próximos 5 años.
Como principal estrategia se busca posicionar un producto diferencial de apoyo a la alimentación saludable en el mercado peruano.Today, Peruvian government establishes healthy protection norms for children in order to protect their health. For that reason, the food industry and Peruvian consumer have been changing their shopping habits and healthy consumption. Faced with these changes, it has been detected the opportunity to offer a healthy and nutritious food product contributing to the health of Peruvian children. “Power Eggs” seeks to position itself on the Peruvian market in segments A, B and C as a nutritional supplement, providing mothers with an alternative nutrition for the daily consumption of children. The market we aim for is made up of 9, 485,406 women with children between the ages of 0 to 12 years in the city of Lima, for which we have a target market of 1, 171,437 people. One of the main objectives is to reach a 20% of participation on the target, as an annual growth of 10% in the next 5 years. It main strategy is to position a differential product to support healthy eating in the peruvian market.
Trabajo de investigación
49
Bapi, Raju V. "On power flows and optimal power flows of integrated power systems". Thesis, 1990. http://localhost:8080/xmlui/handle/12345678/5434.
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50
Tudu, Jaynarayan Thakurdas. "Power Issues in SoCs : Power Aware DFT Architecture and Power Estimation". Thesis, 2016. http://etd.iisc.ac.in/handle/2005/3003.
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Test power, data volume, and test time have been long-standing problems for sequential scan based testing of system-on-chip (SoC) design. The modern SoCs fabricated at lower technology nodes are complex in nature, the transistor count is as large as billions of gate for some of the microprocessors. The design complexity is further projected to increase in the coming years in accordance with Moore's law. The larger gate count and integration of multiple functionalities are the causes for higher test power dissipation, test time and data volume. The dynamic power dissipation during scan testing, i.e. during scan shift, launch and response capture, are major concerns for reliable as well as cost effective testing. Excessive average power dissipation leads to a thermal problem which causes burn-out of the chip during testing. Peak power on other hand causes test failure due to power induced additional delay. The test failure has direct impact on yield. The test power problem in modern 3D stacked based IC is even a more serious issue. Estimating the worst case functional power dissipation is yet another great challenge. The worst case functional power estimation is necessary because it gives an upper bound on the functional power dissipation which can further be used to determine the safe power zone for the test.
Several solutions in the past have been proposed to address these issues. In this thesis we have three major contributions: 1) Sequential scan chain reordering, and 2) JScan-an alternative Joint-scan DFT architecture to address primarily the test power issues along with test time and data volume, and 3) an integer linear programming methodology to address the power estimation problem. In order to reduce test power during shift, we have proposed a graph theoretic formulation for scan chain reordering and for optimum scan shift operation. For each formulation a set of algorithms is proposed. The experimental results on ISCAS-89 benchmark circuit show a reduction of around 25% and 15% in peak power and scan shift time respectively.
In order to have a holistic DFT architecture which could solve test power, test time, and data volume problems, a new DFT architecture called Joint-scan (JScan) have been developed. In JScan we have integrated the serial and random access scan architectures in a systematic way by which the JScan could harness the respective advantages from each of the architectures. The serial scan architecture
from test power, test time, and data volume problems. However, the serial scan is simple in terms of its functionality and is cost effective in terms of DFT circuitry. Whereas, the random ac-cess scan architecture is opposite to this; it is power efficient and it takes lesser time and data volume compared to serial scan. However, the random access scan occupies larger DFT area and introduces routing congestion. Therefore, we have proposed a methodology to realize the JScan architecture as an efficient alternative for standard serial and random access scan. Further, the JScan architecture is optimized and it resulted into a 2-Mode 2M-Jscan Joint-scan architecture. The proposed architectures are experimentally verified on larger benchmark circuits and compared with existing state of the art DFT architectures. The results show a reduction of 50% to 80% in test power and 30% to 50% in test time and data volume. The proposed architectures are also evaluated for routing area minimization and we obtained a saving of around 7% to 15% of chip area.
Estimating the worst case functional power being a challenging problem, we have proposed a binary integer linear programming (BILP) based methodology. Two different formulations have been proposed considering the different delay models namely zero-delay and unit-delay. The proposed methodology generates a pair or input vectors which could toggle the circuit to dissipate worst power. The BILP problems are solved using CPLEX solver for ISCAS-85 combinational benchmark circuits. For some of the circuits, the proposed methodology provided the worst possible power dissipation i.e. 80 to 100% toggling in nets.