Made available in DSpace on 2018-08-02T00:15:14Z (GMT). No. of bitstreams: 1 tese_9757_DISSERTAÇÃO VERSAO FINAL CRISTINA OLIVEIRA DOS SANTOS.pdf: 2587620 bytes, checksum: 826573c65de46133445fe1e7bf1ca70d (MD5) Previous issue date: 2016-03-30 / Esta pesquisa consiste em investigar a comunidade virtual do grupo Borboletas no WhatsApp que promove interação entre pessoas do sexo feminino com idades entre 10 e 35 anos que são pró-transtornos alimentares, as chamadas pró-anas e pró-mias brasileiras, adeptas da prática da anorexia e bulimia, respectivamente. O recorte desse grupo se justifica por elas serem mais ativas dentro das comunidades virtuais, interagindo com maior frequência e construindo vínculos sociais. Utilizarei a etnografia virtual ou netnografia para descobrir as visões de mundo, construções de identidades e relações de sociabilidade que estão sendo criadas pelas participantes, além da análise de redes sociais virtuais. Como resultado dessa dissertação foi possível concluir que as pró-anas e pró-mias têm conhecimento dos efeitos negativos desses transtornos em seus corpos e em suas vidas, mas acreditam que todo o sacrifício para conseguirem alcançar seus desejos de ter um corpo magro são válidos porque as afastam da lipofobia, uma forma de demonização da gordura. Além disso, o apoio constante das participantes nas comunidades virtuais mostrou ser algo tão forte a ponto de criar vínculos entre pessoas que outrora eram desconhecidas e que agora assumiram tal importância na vida das pró-anas e pró-mias que suas vidas giram em torno do transtorno alimentar e das amizades estabelecidas dentro do grupo Borboletas.

Made available in DSpace on 2014-06-12T15:03:33Z (GMT). No. of bitstreams: 2 arquivo1079_1.pdf: 552636 bytes, checksum: 9f6b923de6b6d7422e13453221018bbc (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Universidade Federal de Pernambuco / Essa dissertação buscou examinar o comportamento do consumidor on-line com base na teoria do fluxo (CSIKSZENTMIHALYI, 1975), construto que vem sendo estudado como fonte de entendimento do comportamento do consumidor virtual, bem como sua relação com as emoções vivenciadas no processo de compras on-line de bens ou serviços, que foram medidas pela Escala Diferencial de Emoções - DES (IZARD, 1977). Desse modo, procurou-se investigar as emoções do consumidor e a sua relação com o estado de fluxo dentro do contexto de compras on-line. Para tanto se utilizou o método de pesquisa exploratória descritiva, de corte transversal com a aplicação um survey junto a uma amostra nãoprobabilística de 306 consumidores virtuais. Os dados foram coletados através de questionário e foram analisados por meio de técnicas estatísticas descritivas e multivariadas. Os resultados indicaram que as emoções positivas se relacionam diretamente com o estado de fluxo, favorecendo o comportamento de navegação e conseqüente compra pela internet. Foi verificado ainda que as emoções positivas tanto influenciam o estado de fluxo, como também faz parte do mesmo, visto que o prazer faz parte desta condição. Este estudo, embora ofereça uma visão parcial do comportamento do consumidor on-line, é um passo significativo para um melhor entendimento do mesmo, contribuindo com o fortalecimento da teoria, possibilitando as organizações importante fonte de vantagem competitiva e aos consumidores, o entendimento da natureza e funcionalidade do e-commerce, habilitando-os a explorar as muitas vantagens oferecidas por este meio, tais como: facilidade, praticidade e rapidez no atendimento de suas necessidades

Made available in DSpace on 2014-06-12T22:58:44Z (GMT). No. of bitstreams: 2 arquivo885_1.pdf: 1277229 bytes, checksum: 55aa780c5612de26d86b4455b2b19a7e (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / As pesquisas sobre compreensão de textos adotam a metodologia off-line, que consiste em avaliar a compreensão após a leitura, e a metodologia on-line, que consiste em avaliá-la durante a leitura, sendo a off-line a mais tradicionalmente adotada. Pesquisas mostram que a metodologia on-line é eficaz na investigação de determinados aspectos da compreensão de textos, por exemplo, as inferências de previsão. No entanto, sua possível contribuição para o desenvolvimento da habilidade de estabelecer inferências parece ainda não ter sido explorada. O presente estudo objetivou examinar se a metodologia on-line contribuiria para a compreensão de textos, especificamente no que se refere ao estabelecimento de inferências em crianças com dificuldades nesta área. A escolha das inferências como objeto de investigação deve-se ao fato de sua reconhecida relevância no processo de compreensão textual, como mostra a literatura. Participaram do estudo 80 crianças de ambos os sexos com média e muita dificuldade de compreensão, porém sem dificuldade de decodificação na leitura, alunas do 3º e 4º anos do ensino fundamental em escolas públicas do Recife. Os participantes foram igualmente divididos em quatro grupos: Grupo G1 (on-line apenas), que realizou a leitura interrompida e respondeu perguntas inferenciais após cada interrupção; Grupo G2 (on-line com perguntas complementares), cujo procedimento foi semelhante ao do Grupo G1, porém acrescentando, após cada pergunta inferencial, perguntas complementares que investigavam as bases de geração das inferências; Grupo G3 (off-line com interrupções), que fez a leitura interrompida, sendo apenas indagado aos participantes se entenderam o trecho lido e se gostariam de relê-lo; e Grupo G4 (off-line apenas), que leu o texto sem interrupções. Após a leitura, todos os participantes responderam perguntas inferenciais acerca da história lida, relativas à compreensão global, e a conteúdos específicos. As respostas foram classificadas em categorias hierárquicas: I (não responde), II (resposta problemática ou indevida), III (resposta imprecisa) e IV (resposta precisa). Comparações entre os grupos mostraram que o desempenho do grupo G2 (on-line com perguntas complementares) foi superior ao dos demais, indicando que a associação de perguntas complementares de natureza metacognitiva a perguntas on-line de natureza inferencial foi a mais favorável à compreensão textual, estimulando respostas mais precisas e explícitas. O desempenho não variou em função do tipo de pergunta (global e específica) em qualquer um dos grupos. Uma análise dos erros encontrados identificou quatro tipos de erro que expressam formas particulares de pensar. Dois destes erros mostram uma tentativa de integrar informações, enquanto os outros dois não. Os tipos de erro não variavam em função dos grupos e nem dos tipos de perguntas, concluindo-se que o tipo de erro apresentado pelo leitor é algo estável, um modo limitado de acessar o texto. Foi realizada ainda uma análise individual dos participantes, os quais foram classificados em níveis de compreensão. Esta análise mostrou que foram os participantes do grupo G2 que mais tenderam a um nível de compreensão mais elaborado, corroborando a hipótese de que a metodologia on-line com perguntas complementares é eficaz em melhorar a compreensão

Diploma thesis is focused on usability of software AviX and on analysis of selected manufacturing processes for division of transformer in the ABB company. The first part analyzes the usability and suitability of software AviX for the production and thereby confirm or disprove whether it is suitable to continue to invest in the software license. The next section deals with the analysis and work measuring on the selected production workplaces. The draft chapter contains solutions to eliminate waste occurring in the processes.

Nous nous intéressons à la mise en oeuvre effective d'applications temps réel dans une approche d'ordonnancementhors-ligne de systèmes de tâches périodiques. L'ordonnancement hors-ligne consiste à rechercher avantl'exécution de l'application une séquence pire cas, c'est-à-dire une suite de blocs indiquant une date de débutet de fin d'exécution d'une instance de tâche. Mettre en oeuvre une séquence suppose de spécifier ce qui doit sepasser quand les durées d'exécution réelles sont inférieures aux durées pire cas prévues par la séquence. Notrepremière contribution consiste en la proposition de deux politiques de mise en oeuvre : une politique inflexiblequi respecte strictement les dates de début des blocs ; et une politique flexible qui permet de les avancer. Nousprouvons que ces politiques préservent la validité des séquences. Nous proposons ensuite un modèle de coûtspour l'évaluation et la comparaison de techniques respectant les politiques proposées. La seconde contributionconcerne la proposition de techniques de mise en oeuvre. Dans un premier temps, nous proposons sept techniquesde mise en oeuvre dans un contexte de tâches indépendantes et séquences sans préemption. Nous étendonsensuite l'utilisation de ces techniques aux séquences avec préemption, et aux tâches partageant des ressourcescritiques ou soumises à des contraintes de précédence. La troisième contribution concerne la mise en oeuvresous Posix. Nous présentons des outils de génération de code issus de l'ingénierie dirigée par les modèles. Nousproposons également un outil d'observation de séquences effectives. Enfin, une étude de cas présente l'utilisationpratique de notre approche. / We address the implementation of periodic task sets for off-line scheduling. Off-line scheduling approach consistsin computing a worst-case schedule before runtime. Implementing a schedule requires to specify what must happenwhen the actual execution times of tasks are lower than the planned execution times. The first contributionconsist of the formalization of implementation policies. These policies consider the date by which a task maystart execution, which may or not occur before the planned start time. The inflexible policy does not allowa task to run before its planned start time, the flexible policy does. Since many implementations can complywith these two policies, we also propose a cost model which enables to perform some comparisons betweenthese implementations. The second contribution is the proposition and the presentation of a set of algorithmswhich implement the pre-computed schedules. We first deal with independent task sets in a non preemptivecontext. These algorithms are then adapted to be used in the context of preemptive scheduling, with sharedcritical ressources and precedence constraints. Using the model driven engeneering, we next provide a Posixcode generation tool. We also present a schedule observation tool. Finally, our work has been tested through apratical case study.

Abstract In the first part of this study, determination of the dielectric properties of the low loss microwave ceramic material, barium nonatitanate (Ba2Ti9O20), around 1 GHz is discussed. The structures under test were coaxial resonators, the cores of which were made of barium nonatitanate and the metallization was realised by thick film silver. The measured value of the real part of the relative dielectric constant was εr = 37 and that of the loss tangent was tan σ = 0.00014. The change of the resonance frequency of the coaxial resonators with temperature, in the range -20 … +80 C, was 4 ppm/ C. In addition, realisation of compact interdigital and comb-line bandpass filters was demonstrated for the 900 MHz mobile phone band. Besides Ba2Ti9O20, Ba(Sm,Nd)2Ti5O14 ceramic material with a dielectric constant of εr = 78 was also employed in order to improve the miniaturisation. The volume of the smallest filter was 2 cm3 and the weight was 9 g. In the second part of this study, various measurement methods have been demonstrated to determine the real part of the relative permittivity of FR4 fibreglass circuit board. Test structures were straight asymmetric open-circuited strip lines. It was found that the real part of the relative permittivity decreased slightly with frequency. At 0.72 GHz and 4.5 GHz, εr values of 4.3 and 4.1, respectively, were measured. All the characterisation methods used gave consistent values for εr, and electromagnetic simulators were used to verify the results. In the third part of this study, the structures under test were microstrip or strip line transmission lines, the S parameters of which were measured by using on-wafer measurement techniques. It was found that the insertion loss of the 10 mm long etched Cu microstrip was slightly less than that of the Ag microstrips which were manufactured by etching and gravure offset printing techniques, respectively. The performance of the Ag microstrips was, however, similar. In addition, a theoretical basis was established for the determination of εr of the dielectric substrate and the attenuation coefficient of the transmission lines under test. The calculations were based on signal flow diagrams. The method was applied to determine the dielectric and loss properties of a commercial, Kyocera, Japan, LTCC (Low Temperature Cofired Ceramic) material up to 50 GHz. The measured value of the real part of the relative permittivity was εr = 5.7, and the loss tangent was approximately tan σ = 0.003. The essential idea behind the studies reported in this thesis was twofold. First, the studies aimed at characterising dielectric media which find usage in the realisation of UHF, microwave or millimetre wave circuits. Second, the studies aimed to obtain data of immediate value in practical design work. For this reason, the structures under test were transmission lines having extensive usage in practical high frequency circuit design.

This thesis describes an optical fibre network that uses a bus topology and Code Division Multiple Access (CDMA). Various potential configurations are analysed and compared and it is shown that a serious limitation of optical CDMA schemes using incoherent correlators is the effect of optical beating due to the presence of multiple incoherent optical signals at the receiver photodiode. The network proposed and analysed in this thesis avoids beating between multiple optical fields because it only uses a single, shared, optical source. It does this through the SLIM (Single Light-source with In-line Modulation) configuration in which there is a continuously-operating light source at the head-end of a folded bus, and modulators at the nodes to impose signals on the optical field in the form of pulses of darkness which propagate along the otherwise continuously bright bus. Optical CDMA can use optical-fibre delay-line correlators as matched filters, and these may be operated either coherently or incoherently.Coherent operation is significantly more complex than incoherent operation, but incoherent correlators introduce further beating even in a SLIM network. A new design of optical delay-line correlator, the hybrid correlator, is therefore proposed, analysed and demonstrated. It is shown to eliminate beating. A model of a complete network predicts that a SLIMbus using optical CDMA with hybrid correlators can be operated at TeraBaud rates with the number of simultaneous users limited by multiple access interference (MAI), determined only by the combinatorics of the code set.

Compared to the history of science, spectroscopy at terahertz frequencies is a relatively recent development. Terahertz instruments were initially large and inefficient due to the characteristics of available technology. With progress in materials science and miniature circuit manufacturing techniques, we may fabricate micro-meter scale devices to generate and detect terahertz radiation. However, the complete spectroscope apparatus remains large due to the use of components such as lenses and mirrors designed in the far-field optical regime. A truly miniature terahertz spectroscope would be designed without lenses and mirrors to enable a wide range of inexpensive and pervasive applications in diverse fields such as medicine, materials identification, and security. We present detailed evaluation of some candidate structures for a quasi-optical device and design criteria for a quasi-TEM transmission-line based device. Quasi-TEM transmission lines are inherently broadband and therefore suited for use in a spectroscope. / Graduate

This is a report on my thesis work on bachelor level that took place on SSAB Oxelösund during the spring of 2018. The work has revolved around concept development of an installation for hardness measuring in their production line, and has furthered the development of an existing project. During the last years, different aspects of the project have been analyzed to bring the project closer to a realization.The work has focused around taking a closer look on a concept of a unit meant to perform surface preparation, indentations and topographical analysis of steel plate. The goal is to install this in a so called in-line solution, using a portal over the production line as a basis. This has involved function analysis, establishing target specifications and suggest existing components that can fit those. To define the demands for the target specifications, tests have been performed on vibration factors on the suggested installation place, and laser as a means to clean steel surfaces have been tried out.The result have been an advancement on earlier concepts. Suggestions have been made regarding components, sub functions have been further defined, environmental factors have been analyzed and new technology for surface preparation have been successfully tried out.

In the thesis the author attempts to discover whether or not The Value Line Investment Survey shows evidence of an ability to forecast "Probable Twelve Months Market Performance Rank," a ranking of stocks according to their probable relative price performance within the succeeding twelve months. To test the ability to forecast, the author determines the significance of the correlation between the ranking of stocks according to the forecast and the ranking of stocks according to the observed relative price performance within the year. The conclusion drawn is that The Value Line Investment Survey does not show evidence of a consistent ability to forecast "Probable Twelve Months Market Performance Rank." The author also presents a model of the process which may underly the generation of stock market price changes. The author tests the assumption of the independence of price changes, a part of the model, on the data of the thesis and finds that the test results do not refute the assumption. The model, the "Random Walk Hypothesis," is related to the ability of The Value Line Investment Survey to forecast "Probable Twelve Months Market Performance Rank." It is concluded that The Value Line Investment Survey has failed to show that its forecasts are superior to forecasts based solely on past prices where the market is assumed to follow a random walk. / Business, Sauder School of / Graduate