Ingeniero Civil Electricista / La penetración de las fuentes de energía renovable, que generalmente se caracterizan por operar de manera intermitente, con velocidad y frecuencia variable, hace necesario el uso de conversores para conectar estas fuentes a la red eléctrica, que opera con tensiones y frecuencias constantes. La tecnología de conversores no ha dejado de evolucionar, nuevas topologías de conversores están ingresando a la industria, el objetivo de esta memoria es presentar las topologías multiniveles y profundizar en la topología del conversor de tres niveles de neutro enclavado por diodos (NPC). Las ventajas principales de estos dispositivos respecto a los conversores convencionales de dos niveles son: Mejor calidad de corriente que se refleja en menor THD y la posibilidad de reducir la frecuencia de switching y con ello aumentar la eficiencia en la conversión de energía. Estos inversores tienen aplicaciones en muchos ámbitos de la industria eléctrica, como en los sistemas de conversión eólicos, sistemas fotovoltaicos, mejora de la calidad del producto energía eléctrica, motores de velocidad variables, entre otras. El objetivo específico de este trabajo es operar un inversor de tres piernas usando la modulación SVM de vectores virtuales, a baja frecuencia de switching. El desarrollo del trabajo llevó a que lograr esto era bastante complejo, debido a desbalances inesperados de la tensión de los condensadores del DC-LINK lo que requirió modificar la modulación de vectores virtuales e implementar una estrategia de lazo cerrado para estabilizar la tensión de los condensadores, pero conservando el núcleo de la modulación de vectores virtuales. La lógica utilizada fue no suponer a priori que la modulación de vectores virtuales por si sola logra estabilizar la tensión, sino buscar un espacio de trabajo donde se pudiera sintetizar correctamente la tensión de salida y además lograr estabilizar la tensión de los condensadores del DC-LINK, para ello fue necesario definir las funciones de desviación de tensión y encontrar de manera veloz las soluciones de estas ecuaciones, utilizando técnicas de optimización lineal. Los resultados obtenidos fueron satisfactorios ya que se pudo sintetizar correctamente la tensión y además estabilizar la tensión de los condensadores operando a baja frecuencia de switching. El costo de esto fue que la complejidad computacional aumento ostensiblemente, pero un análisis matemático e informático más profundo podría simplificar la solución conservando sus cualidades.

An essential part of the video game experience are the characters. How the characters are perceived as believable can make or break the immersion of the experience. This paper aims to create a model which can be used as a tool for analysis, designed to measure believability in video game characters. For consistency, we first define the term believability. Using thematic analysis, we aim to evaluate what components are relevant in the design process of a new model. This is achieved by studying three characters from japanese role playing games using two existing models to measure believability in artificial agents, as this hasn't been done in this context in the past. The results show that relevant components in existing models does indeed exist, but they lack some components mirroring feelings and personal development in characters from japanese role playing games. In addition to this, problems arising from the categorization of characters in models designed to measure believability is discovered. Two versions of the new model are presented, one designed to measure characters from various genres, and one designed to specifically measure characters from japanese role playing games. A different approach to categorize video game characters is also presented in the latter version of the new model.

Magíster en Ciencias de la Ingeniería, Mención Eléctrica. Ingeniero Civil Eléctrico / Actualmente existe un gran interés y compromiso en aumentar la generación eléctrica proveniente de fuentes ERNC (Energías Renovables No Convencionales) a nivel mundial dado el actual escenario energético. Para maximizar la transferencia energética y asegurar una operación óptima desde un punto de vista técnico y económico se han propuesto distintas topologías de inversores junto con sus estrategias de control. Por otro lado, el control predictivo se perfila como una estrategia prometedora para controlar algunas topologías de inversores de potencia, en particular el control FS-MPC (Finite Set - Model Predictive Control) se ha implementado en un gran número de configuraciones debido a sus ventajas como: rápida respuesta transitoria; fácil inclusión de no linealidades y restricciones en el controlador; y ausencia de modulador. Sin embargo las tensiones sintetizadas por esta estrategia poseen una frecuencia de conmutación variable lo que complica el diseño de filtros de conexión a la red y aumenta la distorsión armónica en las señales inyectadas. En esta tesis se implementa de forma experimental un control predictivo modulado (M2PC, Modulated Model Predictive Control) en un inversor NPC (Neutral Point Clamped) trifásico de 3 niveles en configuración front-end, esta estrategia genera una tensión con frecuencia de conmutación fija y además mantiene las ventajas del control FS-MPC ya mencionadas. El controlador se programa en una plataforma dSPACE dS1103, para esto fue necesario diseñar y construir una tarjeta de desarrollo para una FPGA (Field-Programmable Gate Array) Spartan 3 y una tarjeta transmisora de fibra óptica, la función de la primera tarjeta es gestionar el envío de vectores al conversor NPC y habilitar un sistema de protección que apague el inversor en caso de falla, mientras que la segunda tarjeta se utiliza para enviar los pulsos de disparo a los IGBT (Insulated-Gate Bipolar Transistor) del inversor. En el desarrollo de esta tesis se proponen 2 estrategias de control M2PC, en la primera se utiliza una función multiobjetivo para regular la corriente inyectada a la red y el balance de los condensadores del DC-Link, mientras que en la segunda el control M2PC sólo se encarga del error de corriente y en una etapa posterior se regula las tensiones del DC-Link. Inicialmente la estrategia se simula mediante el software Plecs y posteriormente se implementa en el sistema experimental. Se concluye que ambas estrategias presentan un buen desempeño en régimen permanente y transitorio, en ambos casos el THD (Total Harmonic Distortion) es menor al 2% y los condensadores se encuentran balanceados.

I dagens allt mer stora och öppna RPG-spel (role-playing game) finns behovet av ett system som kan sprida kunskap om spelvärlden eller aktiviteter till spelaren genom konversationer med spelets NPC:er (non-playing characters). Problemet med dagens spel såsom The Elder Scrolls V: Skyrim är att de NPC:er som har tänkts förmedla sådan här kunskap till spelaren, tilldelas den artificiellt beroende på hur långt spelaren har kommit i spelet. Detta upplevs ofta som orealistiskt då dessa spel mestadels utspelar sig i fantasy-världar utan direktkommunikation såsom telefon, radio, etc. Kunskap bör alltså inte färdas snabbare än vad någon enskild spelkaraktär kan färdas. Då är det självklart att spelare upplever det som orealistiskt när NPC:er har kunskap om tidigare händelseförlopp i spelet där spelaren själv var inblandad, innan de ens har träffat NPC:n.Syftet med det här arbetet är att ta fram ett mer sofistikerat system där kunskap om spelvärlden och om aktiviteter åt spelaren, färdas mun-till-öra mellan NPC:erna. Spelaren kan sedan starta konversationer med diverse NPC:er för att själv samla på sig denna kunskap. T.ex. om var en skatt ligger begraven eller om en drake som behöver dräpas.Varje NPC kommer att ha rutiner och kommer befinna sig på olika platser vid olika tider på dygnet. De kommer konversera med olika typer av NPC:er och kommer ha olika personligheter som avgöra vilken kunskap de vill förmedla vidare och till vem.Vi finner att vi, i implementationen kan skapa ett system där NPC:er följer rutiner som bestämmer var de befinner sig under dagen samt ett konversationssystem som använder deras tilldelade personlighetsattribut för att få dem att samtala med diverse andra NPC:er och på så sätt sprida kunskapen genom spelvärlden. Dock finner vi även att ett mer avancerat rutin- och konversationssystem tillsammans med mer välplanerade rutiner hade gett ett bättre resultat. / In today's ever larger and more open RPG-games (role-playing game) there is a need for a system that can spread knowledge about the game world or of quests for the player through conversations with the game's NPCs (non-playing characters). The problem with games like The Elder Scrolls V: Skyrim (Bethesda Softworks 2011) is that the NPCs that are meant to share their knowledge to the player are artificially given that knowledge depending on how far the player has progressed through the game. This is often perceived as unrealistic as these games mostly take place in fantasy worlds where there is no direct communication such as telephones or radio. This means that knowledge shouldn't be able to travel faster than any game character could. It is no surprise then that players find it unrealistic when NPCs know about some previous event that the player partook in, before they've even met.The purpose of this project is to develop a more sophisticated system where knowledge about the game world and about quests for the player, travels via word of mouth between the NPCs. The player can then start conversations with NPCs to collect this knowledge. E.g. about the location of a buried treasure or a dragon somewhere that needs to be slain.Each NPC will have certain routines and will be located in different places at different times of the day. They will all converse with different types of other NPCs and will have different personalities which determines what knowledge they want to share and to whom.We find that we can, in the implementation create a system where NPCs follow routines which decides where they go during the day. And a conversation system that uses their given personality traits to make them to converse with various other NPCs in the game world. However, we also find out that a more advanced routine and conversation system together with a more better planned set of routines could give a better result.

Detta arbete fokuserar på de romanser som spelare kan inleda med icke-spelbara karaktärer samt vilken påverkan könsrelaterade stereotyper har på dessa. För att undersöka detta har det utvecklats ett textbaserat spel där deltagarna fick möjlighet att välja mellan karaktärer som porträtterar könsrelaterade stereotyper samt icke-stereotyper. Deltagarna intervjuades sedan skriftligt och en analys av den insamlade datan tyder på att spelare föredrar kvinnliga karaktärer som lever upp till stereotypiska ideal. För framtida arbeten skulle det vara intressant att även fråga deltagare efter deras sexuella läggning, då det i nuläget var en majoritet som inledde en romans med en kvinnlig karaktär och data således var något bristande för manliga karaktärer.

Made available in DSpace on 2016-12-12T20:27:39Z (GMT). No. of bitstreams: 1 Luiz Ricardo Lima.pdf: 7933900 bytes, checksum: 225fa96a5d447127d12b2a23f0483893 (MD5) Previous issue date: 2011-08-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents a study about the NPC (Neutral Point Clamped) three-level inverter with a modified Undeland snubber and using a Buck-Boost converter to regenerate the energy processed by the snubber. Initially, qualitative and quantitative analysis of this inverter with the presence of the snubber are presented and a project methodology is proposed. The same analysis and project are presented for the Buck-Boost converter and it is shown that this converter can operate under ZVS (Zero Voltage Switching). Next, mathematical models of all circuitry necessary for the realization of the digital control of the inverter are presented and a controller is projected. Using data of the projected NPC inverter, Buck-Boost converter and digital controller, simulation results are presented. These simulations were done using software s Orcad Pspice and Simulink. Finally, implementation details and experimental results of a 1.5 kW, 800 V input voltage, 127 V output voltage and 200 kHz switching frequency prototype are presented. / Este trabalho apresenta um estudo do inversor NPC (Neutral Point Clamped) a três níveis com snubber de Undeland modificado, utilizando um conversor Buck-Boost para regeneração da energia processada pelo snubber. Inicialmente são feitas analises qualitativa e quantitativa desse inversor com a presença do snubber e é apresentada uma metodologia de projeto. As mesmas analises e projeto são feitos para o conversor Buck-Boost e é mostrado como ele pode operar com comutação ZVS (Zero Voltage Switching). A seguir são mostrados os modelos matemáticos de todos os circuitos necessários para se realizar o controle digital do inversor e é apresentado um projeto de controlador digital. Utilizando os dados de projeto do inversor NPC, do conversor Buck-Boost e do controle são apresentados os resultados de simulações feitas nos programas Orcad Pspice e Simulink. Por ultimo, são apresentados detalhes de implementação e resultados experimentais de um protótipo de 1,5 kW, 800 V de tensão de barramento, 127 V de tensão de saída e 200 kHz de freqüência de comutação.

La maladie de Niemann-Pick de type C (NPC) est une lipidose lysosomale complexe due à une mutation d’un des gènes NPC1 ou NPC2, qui codent pour ces protéines localisées dans les compartiments endo-lysosomaux (LE/LY). Leur absence altère le trafic intracellulaire et induit l’accumulation du cholestérol (Chol) dans les LE/LY. De plus, l’AnxA6 semble participer au transport vésiculaire du Chol en interagissant avec les microdomaines membranaires enrichis en Chol, ou avec le Chol lui-même. Dans ce travail, nous avons isolé des microdomaines membranaires résistant au Triton X-100 (également appelés DRMs pour detergent resistant membranes) à partir de lignée cellulaire NPC L1 ou de cellules saines. Les fibroblastes NPC contiennent plus de DRMs que les fibroblastes sains. Ceci semble être corrélé aux problèmes de transport du Chol dans les cellules NPC. Nous avons aussi montré qu’en présence de calcium, une partie de l’AnxA6 est associé aux DRMs, suggérant que l’AnxA6 participe à l’organisation de la membrane et par ce bias à l’étiologie de la maladie de NPC. Nous avons alors analysé les interactions de l’AnxA6-1 avec les microdomaines riches en Chol ainsi que l’implication de sa région flexible et de la séquence VAAEIL dans ces interactions. Leurs interactions avec des monocouches de Langmuir constituées de phosphatidylcholine, Chol et/ou d’acétate de cholestéryle. Nos résultats montrent que l’AnxA6 a la plus grande affinité pour les monocouches contenant du Chol ainsi que l’implication du groupement hydroxyle du Chol lors de ces interactions. / The Niemann-Pick type C (NPC) disease is a lysosomal lipid storage disorder caused by mutations in one of the two genes NPC1 or NPC2 encoding proteins of the late endosome/lysosome compartment (LE/LY). Defect in these proteins alters vesicular transport and leads to abnormal accumulation of cholesterol (Chol) in LE/LY. There are some lines of evidence suggesting that annexin A6 (AnxA6) participates in vesicular transport of Chol and may interact with membrane domains enriched in Chol and bind Chol. In this work we characterized the membrane microdomains resistant to Triton X-100, i.e., detergent-resistant membranes (DRMs) isolated from NPC patient-derived fibroblasts and from control cells. NPC cells contain a significantly higher amount of DRMs than the control cells that is consistent with the defect in Chol turnover in NPC cells. We also studied the mechanism of AnxA6 involvement in the NPC-induced changes in the membrane organization and showed that in the presence of calcium some AnxA6 molecules associate with the DRMs. This suggests that AnxA6 may play a role in the membrane lateral organization, contributing thus to the etiology of NPC disease. We then focused on the interaction of AnxA6-1 with Chol-rich membranes and on the involvement of its flexible region and VAAEIL sequence in these interactions. For this purpose, kinetics of the interfacial adsorption of human recombinant AnxA6 to Langmuir monolayers containing phosphatidylcholine, Chol and/or cholesteryl acetate were measured. Our data suggest that AnxA6 exhibits the highest affinity to Chol-containing monolayers and that the hydroxyl group of Chol plays a pivotal role in the AnxA6-lipid interactions in vitro.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Throughout the twentieth century, the supply of electricity, mainly obtained from fossil fuels like oil and coal, it has supported the growth and transformation of the world economy. In the early years of this century, the scenario has changed to a new reality, the need for sustainable development. In other words, the challenge is to gradually replace the traditional sources of electricity from renewable energy sources, in which the solar photovoltaic energy has highlighted. Photovoltaic inverters may be constituted in different ways, presenting in recent decades a high research progress. The main study efforts focus on getting high efficiency, high power density and high reliability, to increase the overall performance of the photovoltaic installation. In this direction, this Master Thesis aims to propose, analyze, design and implement a single-phase grid-tied photovoltaic inverter, which provides high efficiency and high power density. This circuit is called Transformerless Photovoltaic Interleaved Multilevel NPC Inverter , that use uncoupled inductors, Gallium Nitride power transistors and employs interleaving strategy beside the LCL filter, synthesizing 9 levels. Are introduced studies on the operation, modulation and design methodology of power stages, considering the static performance. Results are presented for the 1 kW, in order to support the validity of the proposed topology in conjunction with the standard aspects, especially in relation to THD (Total Harmonic Distortion) of grid current, leakage current, efficiency and power density. / Durante todo o século XX, a oferta de energia elétrica, obtida principalmente a partir dos combustíveis fósseis como petróleo e o carvão mineral, deu suporte ao crescimento e as transformações da economia mundial. Já nos primeiros anos do século atual, o cenário mudou para uma nova realidade, a necessidade do desenvolvimento sustentável. Em outras palavras, o desafio é substituir gradativamente as fontes tradicionais de energia elétrica por fontes de energia renovável, onde a energia solar fotovoltaica tem destaque. Os conversores eletrônicos para sistemas fotovoltaicos, também chamados de inversores, podem ser constituídos de diversas maneiras, apresentando nas últimas décadas um acentuado progresso de pesquisa. Os principais esforços de estudo tem se concentrado em obter alto rendimento, alta densidade de potência e alta confiabilidade, de modo a aumentar o desempenho global da instalação fotovoltaica. Neste horizonte, esta dissertação tem por objetivo propor, analisar, projetar e implementar um inversor fotovoltaico monofásico, para aplicação conectada à rede, de alto rendimento e alta densidade de potência. Esta estrutura é denominada de Inversor Fotovoltaico NPC Multinível Intercalado sem Transformador , que utiliza indutores não acoplados, interruptores de Nitreto de Gálio e emprega a técnica interleaving junto ao filtro LCL, sintetizando 9 níveis. No decorrer do trabalho são introduzidos estudos relativos à operação, modulação, metodologia de projeto e estágios de potência, estabelecendo critérios, enquanto considera a performance estática. São apresentados resultados, observando a potência de 1 kW, com a finalidade de corroborar a validade da topologia proposta juntamente as normativas e aspectos que norteiam a aplicação, especialmente com respeito à THD (Total Harmonic Distortion) da corrente da rede, corrente de fuga, rendimento e densidade de potência.

Made available in DSpace on 2016-12-12T17:38:31Z (GMT). No. of bitstreams: 1 EDUARDO MALDAUN BARRETO.pdf: 3234972 bytes, checksum: 1d2d2b79d8a4946c00677b6193158089 (MD5) Previous issue date: 2011-12-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work present a study of a three level NPC (Neutral Point Clamped), with ZVS (Zero Voltage Switching) and PWM (Pulse Width Modulation) control strategy, using a FPGA (Field Programmable Gate Array) for digital control and switches activation. First, a theoretical study is done, where the main waveforms and operation stages are presented. After, a quantitative study is done in order to implement the NPC inverter. Based on the calculations, the mathematical models for each inverter section are extracted to implement the digital control. The project data is then compiled and simulated on Orcad Pspice and Simulink software. Finally, an 1.5 kW, 800 V input voltage, 127 V or 220 V output voltage, and 200 kHz switching frequency is implemented and the experimental results are compared with theoretical and simulated results / Este trabalho apresenta o estudo de um inversor NPC (Neutral Point Clamped) a três níveis com comutação suave ZVS (Zero Voltage Switching) e controle PWM (Pulse Width Modulation), fazendo o uso de uma lógica programável do tipo FPGA (Field Programmable Gate Array) para controle e acionamento das chaves. Inicialmente é feito um estudo qualitativo do inversor, onde as principais formas de onda e etapas de operação são apresentadas, a seguir são estudados os aspectos quantitativos para, desta forma, efetuar o projeto do inversor. Com o inversor definido, todos os modelos matemáticos de todos os circuitos necessários para se realizar o controle digital do inversor são apresentados, assim como o projeto de um controlador digital. Utilizando os dados de projeto do inversor NPC ZVS PWM e controle, os resultados de simulações feitas nos programas Orcad Pspice e Simulink são obtidos. Por fim, um protótipo de 1,5 kW, 800 V de tensão de entrada, 127 V ou 220 V de tensão de saída e 200 kHz de frequência de comutação é montado e os resultados experimentais são avaliados e comparados com os previamente obtidos numericamente e por simulação.

De flesta nuvarande elfordon drivs med en systemspänning på 400V. En ökning av denna spänning skulle dock bland annat kunna möjliggöra en kortare laddningstid för fordonets batteri. Den högre systemspänningen medför ett antal utmaningar, varav en är att öka spänningsblockeringsförmågan hos spänningsomvandlarens transistorer. Det finns olika sätt att lösa detta problem. Om den vanligast förekommande tvånivåstopologin ska användas måste spänningskapaciteten för dess transistorer ökas. Alternativt kan man använda en topologi med tre nivåer med neutralpunktsanslutning, som inte kräver transistorer med så hög spänningsblockeringsförmåga. Syftet med denna rapport är att jämföra verkningsgraden hos dessa två topologier. Därför estimeras med hjälp av simulering spänningsomvandlarnas förluster och utgångseffekt i stationärt tillstånd över hela driftområdet för en elektrisk maskin som är lämplig för fordonsapplikationer. Olika sätt att estimera förlusterna utvärderades och transistorerna i de två topologierna valdes på ett sätt så att en rättvis jämförelse mellan topologierna kunde säkerställas. Ett antal nyckelparametrar som kan påverka effektiviteten hos spänningsomriktarna utvärderades i simuleringar. De erhållna resultaten tyder på att verkningsgraden hos både två nivå- och tre nivå-topologin med neutralpunktsanslutning är jämförbara för större delen av driftområdet. / Most current electric vehicles operate on a system voltage of 400V. However, increasing this voltage would come with, among other benefits, a reduced charging time for the vehicle’s battery. The higher system voltage does pose a number of challenges, with the increase in voltage blocking capability of the power switches of the voltage source inverter being one of them. There are different ways of solving this problem. If the currently preferred two-level topology is to be used, the voltage rating of its switches needs to be increased. Alternatively a three-level neutral point clamped topology could be used which does not require switches with such a high blocking voltage rating. The purpose of this thesis is to compare the efficiency of these two solutions. Therefore the steady state losses and output power of the voltage source inverters throughout the operating range of an electric machine suitable for automotive application were estimated through simulation. Different ways of estimating the losses were evaluated and the power switches of the two topologies were chosen in such a way that a fair comparison between the topologies could be ensured. A number of key parameters that could impact the efficiency of the voltage source inverters were evaluated in simulations. The obtained results suggest that for the majority of the operating range the efficiency of the two-level and the three-level neutral point clamped topology are closely matched.