O objetivo principal deste trabalho é o desenvolvimento de controladores robustos baseados no princípio do modelo interno, em referenciais síncrono e estacionário, para aplicação ao estágio de saída de uma fonte ininterrupta de energia (UPS) a fim de minimizar a distorção na tensão de saída causada pela conexão de cargas não lineares balanceadas e desbalanceadas. A formulação em referencial estacionário (abc) é realizada através da aplicação de controladores com múltiplos modos ressonantes, a fim de se estabelecer erro nulo ao seguimento de referência senoidal e rejeição de distúrbios na tensão de saída devido às correntes com elevado conteúdo harmônico drenadas pelas cargas. Além disso, o controle é formulado em referencial síncrono (dq0) utilizando controladores Proporcional-Integral (PI) convencionais muito difundidos na maioria das aplicações comerciais de UPS. O projeto de ambos controladores é realizado utilizando uma metodologia de controle robusto com realimentação de estados, onde os parâmetros dos controladores são determinados através da resolução de um problema de otimização convexa sujeito a um conjunto de restrições na forma de desigualdades matriciais lineares (LMI). Uma análise comparativa de desempenho é realizada entre controladores com um modo ressonante (sintonizado na fundamental) e o PI em dq0, pois apresentam estruturas funcionalmente equivalentes sob a ótica do princípio do modelo interno aplicada a seus respectivos referenciais. Além do mais, demonstra-se a melhoria no desempenho com o uso dos controladores múltiplo ressonantes em referencial estacionário onde escolhe-se as frequências de ressonância de cada modo de maneira a suprimir os efeitos de harmônicas específicas na tensão de saída da UPS. A análise comparativa entre os controladores propostos é realizada através de simulações numéricas, utilizando os procedimentos de ensaio dinâmico e estático e as exigências estabelecidas pela norma internacional IEC 62040-3. / The main objective of this work is the development of robust controllers based on the internalmodel principle, in synchronous and stationary frames, applied to the output stage of an uninterruptible power supply (UPS), in order to minimize the output voltage distortion caused by the connection of balanced and unbalanced nonlinear loads. The formulation in stationary abc-frame is accomplished through the aplication of a multiple resonant controller, so that, it is possible to achieve zero-error tracking of the sinusoidal reference and disturbances rejection on the output voltage due to the high amount of harmonic currents drained by the loads. Moreover, a controller in synchronous reference frame (dq0 axis) is formulated through the application of conventional Proportional-Integral (PI) controllers which are widely used in comercial UPS applications. The design of both controllers is formulated using a state-feedback robust controlmethod, in which the controller parameters are determined by solving a convex optimization problem subject to a set of LMI constraints. A comparative analysis on the performance of the single-mode resonant controller (tuned at the fundamental frequency) and the PI controller is performed, because these controllers are functionally equivalent in the sense of the internal model principle applied to their respective frames. Furthermore, the improvement in performance is demostrated with the use of multiple resonant controllers in stationary abc-frame where the resonance frequencies are chosen to suppress the effects of a specific harmonic in the UPS output voltage. The comparative analysis of the proposed controllers is performed through numerical simulations, making use of the dynamical and steady-state test methods and performance requirements defined by the IEC 62040-3 international stardard.

This thesis aims to increase knowledge about the usage and relevance of Project Management (PM) methods and tools within start-up companies, with regard to the previous work experience of the entrepreneur. The underdeveloped connection of PM and entrepreneurship will be further explored by following the research question proposed below that guides the study. What PM methods and tools do entrepreneurs apply in the process of launching the business versus the operation of the start-up, especially considering their previous work experience and contact with PM? In order to answer the proposed research question and pursue the set objectives, the thesis is structured as follows. First, the methodology within this study is represented in theoretical and practical form in chapter 2 and 4. Furthermore, the theoretical context in the field is summarized in chapter 3. The topics of traditional PM and agile PM (APM) with their characteristics and tools are portrayed; especially the latter is extensively presented in chapter 3.2 due to the need of flexibility and adaptability in the highly dynamic business environment nowadays, as well as the strong connection between APM and the IT development sector. Existing theories about the topics of entrepreneurship and start-ups are described in the subsequent chapter, whereby a focus is set on the entrepreneur itself and his or her previous work experience. To summarize the existing theory in the fields of PM and entrepreneurship a conceptual framework was created by the researchers of this study in chapter 3.4, which also serves to represent the findings of the study in the concluding chapter. The empirical findings, which are presented in chapter 5, were organized in chronological order of the conducted semi-structured, qualitative interviews with software development start-ups in Sweden. Valuable results for the research areas of entrepreneurship and PM, as well as for the practical usage in those fields could be generated. The summarized results of this qualitative study are summarized and presented in chapter 6, titled empirical analysis. The authors found out that the majority of the contacted start-ups did not plan a lot in the launching phase of the business, in fact, they did not apply specific PM tools. While the business was growing, so did its complexity, which is why the need for applying PM tools became more present. Even though no clear connection between the previous work experience of the entrepreneur and the applied PM tools could be established, it was noticeable that prior exposure to PM made the entrepreneurs more aware of the methods and tools. They specifically looked for some and used them more knowingly. Further drivers for choosing a PM method and tools were recommendations and personal research. Next to the stage and scale of the business, especially the team size, the location of the team members and their familiarity with each other appeared to influence the decision on using specific tools tremendously. In general, it could be detected in this study, that the APM framework was commonly recognized as highly valuable for start-ups and many of the respondents already follow it or want to do so in the future. Moreover, primarily only one or very few tools were applied within the start-ups to not lose track of the business development and keep everything concise.

nÃo hà / Esta tese de doutorado apresenta duas novas topologias de conversores CA-CC com uso de neutro comum: conversor de cinco nÃveis intercalado e conversor de cinco nÃveis tipo T. AlÃm disso, uma nova forma de implementaÃÃo da tÃcnica de controle indireto da corrente (Indirect Current Control - ICC) à apresentada. Assim, para comprovaÃÃo da praticidade dos conversores apresentados, toma-se como base o conversor CA-CC de trÃs nÃveis convencional e entÃo à realizada uma anÃlise comparativa de desempenho entre esses trÃs conversores CA-CC monofÃsicos para aplicaÃÃo em no-breaks. Os conversores analisados possuem como caracterÃstica comum a correÃÃo do fator de potÃncia, o controle digital realizado por FPGA e a conexÃo da fonte de alimentaÃÃo com o estÃgio de saÃda, facilitando o uso de inversor e by-pass para no-breaks. O primeiro conversor analisado à o conversor de trÃs nÃveis convencional que apresenta como principal caracterÃstica o reduzido nÃmero de componentes. O segundo conversor analisado à o conversor de cinco nÃveis intercalado que apresenta como principal caracterÃstica as reduzidas perdas de comutaÃÃo e conduÃÃo. Finalmente, o terceiro conversor analisado à o conversor de cinco nÃveis tipo T que apresenta como principais caracterÃsticas: reduzidas perdas de comutaÃÃo e conduÃÃo; os elementos magnÃticos operam com o dobro da frequÃncia de comutaÃÃo reduzindo desta maneira o peso e o volume. A anÃlise teÃrica dos conversores monofÃsicos, os conceitos bÃsicos sobre o controle digital e a tÃcnica de modulaÃÃo, a metodologia de projeto, simulaÃÃo e resultados experimentais dos protÃtipos construÃdos sÃo apresentados para validar o princÃpio de funcionamento dos conversores propostos. / This thesis presents two novel topologies of AC-DC converters with common neutral: five-level interleaved converter and five-level T type converter. Besides, a novel type of implementation of Indirect Current Control (ICC) is also presented. Thus, a comparative analysis of performance between three single phase AC-DC converters for UPS applications is realized. The analyzed converters have as common characteristics: power factor correction, digital control using FPGA and connection between input power supply and converter output enabling the use of UPS inverter and by-pass. The first one analyzed converter is the conventional three level converter which presents as main feature reduced numbers of power semiconductors and components. The second one analyzed converter is the five level interleaving converter which presents as main feature reduced conduction and commutation losses. Finally, the last one analyzed converter is the T type five level converter which presents as main features: reduced conduction and commutation losses and magnetic components operating with the double of switching frequency reducing weight and volume. Theoretical analysis of the single phase converters, basics concepts of digital control and modulation technique, design procedure, simulation and experimental results of lab models are presented in order to validate the principle of operation of the proposed converters.

Submitted by MARCOS SILVA (mbcs@hotmail.com) on 2014-01-13T17:17:29Z No. of bitstreams: 1 Dissertacao SILVA MARCOS BARCELLOS DA CUNHA E Versão Final.pdf: 870642 bytes, checksum: 53d7c71ec1229ff707efd8ed4f05f0ae (MD5) / Approved for entry into archive by Vera Lúcia Mourão (vera.mourao@fgv.br) on 2014-01-13T17:26:17Z (GMT) No. of bitstreams: 1 Dissertacao SILVA MARCOS BARCELLOS DA CUNHA E Versão Final.pdf: 870642 bytes, checksum: 53d7c71ec1229ff707efd8ed4f05f0ae (MD5) / Made available in DSpace on 2014-01-13T17:31:19Z (GMT). No. of bitstreams: 1 Dissertacao SILVA MARCOS BARCELLOS DA CUNHA E Versão Final.pdf: 870642 bytes, checksum: 53d7c71ec1229ff707efd8ed4f05f0ae (MD5) Previous issue date: 2013-12-12 / O acesso ao capital por empreendedores em start-ups está tradicionalmente fundamentado na indústria de Venture Capital (VC). Nos países emergentes, incluindo o Brasil, foi somente na última década que essa indústria passou a ter uma importância relativa maior às outras fontes de capital disponíveis. Ocorreu que a indústria passou a contar com a migração de fundos estrangeiros tradicionais atraídos pelo potencial de crescimento, pelas oportunidades de novos negócios e incentivos governamentais nesses países. Dessa forma, pode-se considerar que o desenvolvimento da indústria de VC é algo relativamente embrionário no Brasil. Este estudo tem como objetivo principal identificar quais foram os fatores determinantes para que os investidores (Venture Capital) e os investidos (start-up) decidissem por desenvolver uma sociedade em determinado negócio, sob o contexto institucional brasileiro. A pesquisa qualitativa foi realizada pela abordagem exploratória, a partir de entrevistas em profundidade (quatorze, no total) com investidores e investidos brasileiros que já haviam realizado uma sociedade há até dois anos. As entrevistas totalizaram nove matchings, ou pares de investidores e investidos num negócio. Os resultados oriundos dessas entrevistas demonstraram padrões e processos muito similares aos estudados nos países em que essa indústria é considerada desenvolvida. Os dados demonstram, porém, que no Brasil, como em outros países emergentes, a questão do relacionamento entre investidor e investido representa o principal fator para a realização de um negócio entre as partes. Além disso, indica que o relacionamento interpessoal representa um peso maior quando comparado aos outros fatores identificados na pesquisa.

創業之目的是突破現狀，追求創新，創業家必須擁有資源才能創新產品與服務，但他們卻因資源受限而有志難伸。新創企業如何以拼湊有限資源來翻轉劣勢，是隨創（bricolage）所提倡的主導做法。可是，拼湊資源是透過怎樣的時機，當今文獻卻討論有限，因此，時機辨識成為是當前亟需探索之重點。本研究選取三個原住民族新創企業個案，分析他們的經營歷程、挑戰與如何透過辨識時機進行資源拼湊。本研究發現，原住民族文化是重要的資源，這些在地資源成為識別機會、突破資源稀缺的服務創新關鍵。在學術意涵上，本研究提出三個議題。第一，辨識時機需要觀察資源轉換脈絡；第二，辨識時機需要設定資源使用情境；第三，辨識時機需找出資源調合方式。在實務啟示上，本研究提出辨識時機的各種可能，並歸納多樣的隨創原則。進行隨創時，若能掌握在地文化便可以找出適當時機，讓有限的資源拼湊出無限的創新。 / The objective of entrepreneurship is to seek breakthrough innovation within status quo. Entrepreneurs must obtain resources in order to innovate new products or services. But their aspirations often are frustrated due to resource constraints. The dominant approach to entrepreneurial bricolage is to advise new ventures to turnaround adversities by making-do with resources. But, when could entrepreneurs identify opportunity for tinkering limited resources? This is an inquiry worth further investigation. This research selects three case studies of indigenous start-ups while analyzes their entrepreneurial process and challenges within; and examines how they recognize opportunities in creative resource tinkering. This study found that indigenous culture is a kind of critical local resource, which may trigger opportunity recognition in order to guide resource making-do and achieve service innovation. Theoretically, this study suggests that (1) opportunity recognition must understand the context that is suitable for the transformation of resource quality; (2) opportunity recognition must pay attention to resource deployment in situ; (3) opportunity recognition should identify methods of resource blending. Practically, this study proposes several possibilities of opportunity recognition and summarizes a variety of bricolage principles. When engaging entrepreneurial bricolage, if we could get a grip with local culture, it increases our chance to identify the right moment and allow limited resources to enact unlimited innovation.

The researcher embarked on this study, as the need was identified to investigate whether girls in primary schools have a realistic body image. The hypothesis was made that pressure from society, the media and parents might have a negative influence on a girl’s body image. The goal of this qualitative study was thus to determine how the primary school girl views her body and the influence this view has on her sense-of-self. It was anticipated that the outcome of the study would equip the researcher and social work colleagues with information that can be used in order to make parents and teachers aware of the pressures children experience and the effect this has on their sense-of-self. The exploratory study endeavoured to answer the following research questions: How does the primary school girl view her body, and how does this influence her sense-of-self? The objectives for this study were the following: <ul> <li>To provide a knowledge base on body image, sense-of-self and the perceptions primary school girls have regarding their bodies, based on a literature review.</li> <li>To use gestalt play therapy techniques to investigate the influence of perceptions regarding body image on the sense-of-self.</li> <li>To investigate primary school girls’ body image by means of an empirical study.</li> <li>To draw conclusions and make recommendations regarding the primary school girl’s perception of body image and the influence thereof on her sense-of-self.</li></ul> The study was feasible and consent was gained from the parents, respondents and organization where the study was done. The researcher studied with a bursary and costs were therefore covered by this. Eight respondents were selected at the researcher’s discretion by using certain criteria for selection. Care was given in selecting respondents who were representative of girls in the middle childhood phase. Five themes emerged from the study, namely sensory awareness, body image, the development of body image, the sense-of-self and the link between the sense-of-self and body image. Sub-themes were also identified from these five themes. Two consecutive play therapy sessions were used as data collection methods. From the empirical findings it is evident that the primary school girl’s perception of body image is largely based on the opinions and feedback from significant others. Self talk and self-statements play an important role in the formation of body image in the primary school girl. The study further indicates that body image has a direct influence on all aspects of the primary school girl’s sense-of-self and that a preoccupation with body size and shape amongst primary school girls is common. All of the respondents had hang-ups with regards to some aspect of their physical bodies, wished that they weighed less and indicated that they would want to change something about their bodies. It thus seems that girls in their middle childhood are particularly vulnerable to having a negative body image. From the research findings several conclusions and recommendations were made such as professionals needing to be aware of the potential negative impact that the media, peers and parents have on a child’s body image and sense-of-self. The recommendation was further made that professionals should encourage teachers, parents and child care workers to realize that in order for a child to develop a healthy sense-of-self and accept the way she looks, she has to receive positive feedback from significant others in her life. This study indicates that the primary school girl’s body image is fragile, and that significant others, the media and peers play an important role in the formation of a positive body image in children. / Dissertation (MSD)--University of Pretoria, 2008. / Social Work and Criminology / unrestricted

O empreendedorismo é um fenômeno de abrangência global que tem direcionado a atenção de diversas instituições de ensino, entidades representativas de classe, do terceiro setor e órgãos governamentais, que buscam um melhor entendimento dos fatores que contribuem para o crescimento e desenvolvimento econômico. A ação empreendedora é a mola propulsora responsável pela dinamização da economia, que por meio da introdução de novos produtos e serviços, promove a geração de empregos e a distribuição de renda. Por trás da criação das organizações está a figura do empreendedor, um indivíduo que, partindo de suas ideias e percepções, com criatividade, trabalho árduo e perseverança, administra e assume o risco do resultado de seu empreendimento. No Brasil, das 4,5 milhões de empresas existentes, aproximadamente 1,5%, são responsáveis pela geração de 70% dos postos de trabalho, segundo dados do IBGE. Estas empresas são categorizadas como empresas de alto crescimento ou alto impacto (scale ups), pois apresentam taxas de crescimento acima de 20%. Este estudo objetiva descrever as características de empreendedores que criaram e conduzem empresas de alto impacto, segundo suas próprias percepções. Partindo de uma revisão bibliográfica sobre a importância do empreendedorismo, conceitos e definições, seu impacto no Brasil e no mundo e utilizando-se também de relatórios de órgãos governamentais e instituições apoiadoras e monitoradores da atividade empreendedora, desenvolveu-se uma pesquisa de campo, utilizando-se de entrevistas semiestruturadas, aplicadas por meio de videoconferências. Dessa maneira, entrevistou-se um grupo de indivíduos associados a uma organização não governamental, que atua no fomento da atividade empreendedora no Brasil e em diversos países, e que se enquadram nesse perfil empresarial. Os dados obtidos foram tratados mediante o uso da técnica de análise de conteúdo que identificou 18 categorias que envolvem aspectos pessoais e da criação e do desenvolvimento dos negócios. Pode-se inferir que empreendedorismo de alto impacto é o resultado de uma ideia inovadora, desenvolvida e trabalhada com comprometimento de seu idealizador, ofertando um produto ou serviço diferenciado que agrega um valor singular para os seus clientes. / Entrepreneurship is a global phenomenon that coverage has focused the attention of several educational institutions, professional representative bodies, third sector and government agencies that seek a better understanding of the factors that contribute to the economic growth and development. The entrepreneurial action is the driving force responsible for stimulating the economy, through the introduction of new products and services, promotes job creation and income distribution. Behind the creation of organizations is the figure of the entrepreneur, an individual who, from their ideas and perceptions, with creativity, hard work and perseverance, manages and assumes the risk of the outcome of your venture. In Brazil, the 4.5 million existing businesses, approximately 1.5%, are responsible for generating 70% of jobs, according to IBGE data. These companies are categorized as high-growth or high-impact companies (scale ups), because their growth rates above 20%. This study aims to describe the characteristics of entrepreneurs who created and lead high-impact companies, according to their own perceptions. From a literature review on the importance of entrepreneurship, concepts and definitions, its impact on Brazil and the world and also using government agencies reports and supporting institutions and Listeners of entrepreneurial activity, we developed a field research using If semi-structured interviews, applied through videoconferences. Thus, we interviewed a group of individuals associated with a non-governmental organization that acts in fostering entrepreneurial activity in Brazil and in several countries, and that fit this corporate profile. The data were processed by using the content analysis technique identified 18 categories involving personal aspects and the creation and business development. It can be inferred that high-impact entrepreneurship is the result of an innovative idea, developed and worked with commitment of its creator, offering a product or special service that adds a unique value for its customers.

This thesis deals with the design of a DC/DC converter designed for charging supercapacitors from the 36 V voltage source and consequent back transformation of supercapacitors voltage to the required output voltage. In the thesis the designs of decreasing and increasing DC/DC converters including schematics and calculations of individual components are presented and described. The calculations necessary for the supercapacitors to meet the 10Wh energy condition and the voltage balancer on the capacitors are given below. Completely designed equipment will be assembled and tested on supercapacitors with lower energy.

L’intensité concurrentielle et les évolutions technologiques n’ont jamais été aussi intenses. Aussi, les entreprises en quête de pérennité sont-elles de plus en plus confrontées à une nécessité d’exploiter leurs activités actuelles et d’explorer des activités futures. Or la gestion de ce double impératif est loin d’être évidente, générant potentiellement d’importantes tensions au sein des entreprises. Bien que la recherche en management ait permis de mieux appréhender cette tension d’Exploration/Exploitation, il reste des zones de contradiction et des espaces non explorés. En particulier, il n’y a pas de consensus sur les définitions des concepts d’exploration et d’exploitation, ne permettant pas ainsi de garantir une certaine cohérence dans la recherche (Birkinshaw & Gupta, 2013). D’autre part, la tension Exploration/Exploitation n’a que très peu été étudiée dans le contexte des jeunes entreprises de croissance - également appelées « scale-up » - qui ont la particularité d’être exposées à de forts enjeux de survie. Ainsi, afin de contribuer à une meilleure compréhension des problématiques que soulève cette tension au sein de celles-ci, un format de thèse sur travaux, comprenant trois études complémentaires, est adopté.Au préalable, afin de cadrer conceptuellement la thèse, je réponds, dans une première étude, à l’appel des chercheurs pour la clarification des concepts d’exploration et d’exploitation en proposant une typologie d’exploration. Puis, par l’intermédiaire d’une approche multi-cas longitudinale menée auprès de huit jeunes entreprises de croissance, j’explore tout d’abord, dans une deuxième étude, les facteurs influençant les orientations stratégiques des entreprises quant à leurs activités d’exploration et d’exploitation. Enfin, dans la troisième étude, je cherche à comprendre comment le fonctionnement des équipes de direction définit les rôles de chacun dans les activités d’exploration et d’exploitation. / Competition and technological change have never been as intense as they are today. To survive, companies must increasingly carry out current activities at the same time that they explore future ones. It is no easy task to operate on both of these fronts, and doing so is a potential source of tension and contradiction. Although management research has provided insight into the exploration and exploitation tension, there are still contradictions and unexplored areas. In particular, there is no consensus on the definition of the concepts of exploration and exploitation, which means the research lacks a certain level of consistency. In addition, there has been very little attention paid to the Exploration/Exploitation tension in the context of young, growing “scale-up” companies, which are particularly exposed to threats to their survival. To obtain a better understanding of the situations this tension causes in these companies, we have adopted a multi-paper dissertation consisting of three complementary studies.In the first study, to create a conceptual framework for the thesis, we answer researchers’ call for a clarification of the concepts of exploration and exploitation by proposing a typology of exploration. Then, based on a longitudinal, multi-case approach focused on eight scale-up companies, we first explore, in a second study, the factors influencing firms’ strategic orientations vis-à-vis exploration and exploitation activities. Finally, in the third study, we seek to understand how management teams define their individual roles with respect to exploration and exploitation activities.

Zielsetzung dieser Arbeit war die Zähmodifizierung eines neuen besonders hochtemperaturbeständigen ungesättigten Polyesters, nachfolgend Referenz genannt. Im Rahmen dieser Arbeit wurden verschiedene konzeptionelle Ansätze verfolgt, um die Harz- und Duromer-Eigenschaften von hochtemperaturbeständigen ungesättigten Polyesterharzen (Unsaturated Polyester Resin, UPR) zu modifizieren und zu verstehen.:1. Einleitung 2. Motivation 3. Theoretischer Teil 4. Charakterisierungsmethoden 5. Ergebnisse und Diskussion 6. Zusammenfassung 7. Experimenteller Teil 8. Literaturverzeichnis 9. Anhang 10. Versicherung