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1
Ng, Beng Koon. "Impact ionization in wide band gap semiconductors : Alâ†xGaâ‚â†-â†xAs and 4H-SiC." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251522.
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2
Ållebrand, Björn. "On SiC JFET converters : components, gate-drives and main-circuit considerations /." Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-558.
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3
Voldoire, Adrien. "Outil de développement et d'optimisation dédié aux onduleurs SiC de forte puissance." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT037.
Повний текст джерелаАнотація:
La volonté de diminuer la consommation en carburant en aéronautique amène à repenser les architectures de distribution et de conversion de puissance embarquées. L’utilisation d’un outil d’optimisation déterministe apparait comme une solution prometteuse pour prendre en compte les compromis intrinsèques aux convertisseurs statiques en pré-dimensionnement, avec pour objectif de minimiser leur masse. Un outil d’optimisation est donc proposé pour apporter des éléments de comparaison entre différentes topologies d’onduleur et entre différentes solutions technologiques.Le développement de l’outil passe par l’élaboration de modèles analytiques pour être compatible avec l’utilisation d’un algorithme à base de gradients. Une analyse harmonique reposant sur des transformées de Fourier permet de reconstituer les ondulations de chaque signal, en regard des normes aéronautiques. La modélisation s’intéresse également à la construction de modèles pour les composants passifs et actifs, permettant en particulier d’évaluer les pertes et donc le rendement du convertisseur. L’intégralité des modèles développés fait l’objet d’une validation expérimentale sur un prototype à 10 kW.L’utilisation d’un algorithme à base de gradient n’étant pas classique en électronique de puissance, des études sont menées pour valider la méthodologie proposée. Ces études montrent l’adéquation du choix d’un tel algorithme avec le besoin de pré-dimensionnement, tout en indiquant ses limites et les perspectives. Enfin, l’outil d’optimisation est utilisé pour comparer différentes solutions architecturales et technologiques sur des cas d’application aéronautiques. Les résultats obtenus sont discutés en regard des méthodes de dimensionnement classiquesThe exponential development of aircraft transportation is a threat in the context of global warming. One of the solutions investigated consists in increasing the amount of embedded electrical power systems and actuators. Using a deterministic optimization tool appear as a promising solution to take into account the multiple compromises in a power converter design during the pre-design step, with the goal to minimize the weight. An optimization tool is proposed to bring comparative elements between different inverter topologies and technological solutions.The development of the tool requires elaborating analytical models to be compliant with the gradient-based algorithm. Harmonic analyses with Fourier transform enable calculating the signal ripples, to respect aircraft standards. Components are also designed precisely with appropriate loss models to estimate the converter efficiency. All the developed models are experimentally validated with a 10 kW prototype.As the use a gradient-based algorithm is not common in power electronics, studies are carried out to validate this proposed methodology. These studies show the effectiveness of the algorithm choice in the pre-design step, and indicates some limits and forecasts. Finally, the algorithm is used to compare different architectural and technological solutions on aircraft cases. The results are discussed regarding classical sizing methodologies
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Fonteneau, Xavier. "Conception d’un onduleur triphasé à base de composants SiC en technologie JFET à haute fréquence de commutation." Thesis, Lyon, INSA, 2014. http://www.theses.fr/2014ISAL0059/document.
Повний текст джерелаАнотація:
Depuis le début des années 2000, les composants en carbure de silicium (SiC) sont présents sur le marché principalement sous la forme de diodes Schottky et de transistors FET. Ces nouveaux semi-conducteurs offrent des performances en commutation bien supérieures à celles des composants en silicium (Si) ce qui se traduit par une diminution des pertes et une réduction de la température de fonctionnement à système de refroidissement identique. L’utilisation de composants SiC ouvre donc la possibilité de concevoir des convertisseurs plus compacts ou à une fréquence de commutation élevée pour une même compacité. C’est avec cet objectif d’augmentation de la fréquence de commutation qu’a été menée cette étude axée sur l’utilisation de composants SiC au sein d’un onduleur triphasé. Le convertisseur sur lequel se base l’étude accepte une tension d’entrée de 450V et fournit en régime nominal un courant de sortie efficace par phase de 40 A. Le choix des composants SiC s’est porté sur des transistors JFET Normally-Off et des diodes Schottky SiC car ces composants étaient disponibles à la vente au début de ces travaux et offrent des pertes en commutation et en conduction inférieures aux autres structures en SiC. Les transistors FET possèdent une structure et des propriétés bien différentes des IGBT habituellement utilisés pour des convertisseurs de la gamme considérée notamment par leur capacité à conduire un courant inverse avec ou sans diode externe. De ce fait, il est nécessaire de développer de nouveaux outils d’aide au dimensionnement dédiés à ces composants SiC. Ces outils de calculs sont basés principalement sur les paramètres électriques et thermiques du système et sur les caractéristiques des composants SiC. Les premiers résultats montrent qu’en autorisant la conduction d’un courant inverse au sein des transistors, il est possible de diminuer le nombre de composants. Basées sur ces estimations, une maquette de bras d’onduleur a été développée et testée. Les premiers thermiques montrent que pour une puissance de 12kW, il est possible d’augmenter la fréquence de commutation de 12 kHz à 100 kHzSince 2000, Silicon Carbide (SiC) components are available on the market mainly as Schottky diodes and FET transistor. These new devices provide better switching performance than Silicon (Si) components that leads to a reduction of losses and operating temperatures at equivalent cooling system. Using SiC components allows to a better converter integration. It is in this context that ECA-EN has started this thesis dedicated to using SiC devices in a three-phase inverter at high switching frequency. The converter object of this study is supply by a input voltage of 450V and provides a current of 40A per phase. The components used for these study are SiC Normally-Off JFET and Schottky Diodes because these devices were commercialized at the begining of this thesis and offer better switching performance than others SiC components. FET transistors have a different structure compared to traditionnal IGBT especially their capability to conduct a reverse current with or without body diode. So it is necessary to develop new tools dedicated to the design of converters built with SiC components. These tools are based on the electrical properties of the converters and the statics and dynamics characteristics of the transistor and the diode. The results show that when the transistors conduct a reverse current, the number of components/dies can be reduced. According to data, a PCB board of an inverter leg has been built and tested at ECA-EN. The thermal measurement based on the heatsink shows that the switching frequency of an inverter leg can be increased from 12 to 100 kHz for an ouput power of 12kW
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Alhoussein, Ali. "Caractérisation et modélisation CEM des nouvelles technologie de composants de puissance (SIC). : Application : convertisseurs de puissance." Thesis, Normandie, 2020. http://www.theses.fr/2020NORMR043.
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Avec le développement des nouveaux composants de puissance à grand gap plus performants que leurs homologues en Silicium et l’intégration croissante de ces composants dans le véhicule électrique, la compatibilité électromagnétique est devenue un enjeu important pour le respect des normes de conformité en vigueur. La thèse traite donc les méthodes de modélisation haute fréquence des composants grand gap. Les problèmes liés à la fiabilité et la précision des modèles actuels sont mis en évidence. Ensuite, un nouveau modèle générique est proposé avec des formulations spécifiques lui permettant de mieux reproduire les caractéristiques statiques et dynamiques des MOSFETs en SiC. Des bancs de test ont été mis en place permettant de caractériser ces nouveaux composants avec des précautions spécifiques afin d’améliorer la précision de ces mesures. L’utilisation d’un algorithme génétique développé pour identifier les paramètres du modèle générique proposé, a permis une reproduction fine des caractéristiques mesurées expérimentalement de plusieurs composants SiC ainsi que les perturbations CEM générées dans un convertisseur statiqueWith the development of new large-gap power components with superior performance compared to their Silicon counterparts and the rising integration of these components in the electric vehicle, electromagnetic compatibility has become an important issue for compliance with normative standards. Hence, this thesis discusses the modeling methods of wide bandgap components. Problems related to the reliability of the models and their accuracy are highlighted. Then, a new model is proposed with specific formulations allowing it to better reproduce the static and dynamic characteristics of SiC MOSFETs. Test benches have been set up to characterize these new components with specific precautions in order to improve the precision of the measurements. The use of a developed genetic algorithm to identify the parameters of the proposed generic model, allowed a close reproduction of the characteristics measured experimentally of several SiC components as well as the EMC disturbances generated in a static converter
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Rondon-Pinilla, Eliana. "Conception de convertisseurs électroniques de puissance à faible impact électromagnétique intégrant de nouvelles technologies d'interrupteurs à semi-conducteurs." Thesis, Ecully, Ecole centrale de Lyon, 2014. http://www.theses.fr/2014ECDL0018/document.
Повний текст джерелаАнотація:
Actuellement, le développement de semiconducteurs et la demande croissante de convertisseurs en électronique de puissance dans les différents domaines de l’énergie électrique, notamment pour des applications dans l’aéronautique et les réseaux de transport et de distribution, imposent de nouvelles spécifications comme le fonctionnement à hautes fréquences de commutation, densités de puissance élevées, hautes températures et hauts rendements. Tout ceci contribue au fort développement des composants en SiC (Carbure de Silicium). Cependant, ces composants créent de nouvelles contraintes en Compatibilité Electromagnétique (CEM) à cause des conditions de haute fréquence de commutation et fortes vitesses de commutation (forts di/dt et dv/dt) en comparaison à d’autres composants conventionnels de l'électronique de puissance. Une étude des perturbations générées par les composants SiC est donc nécessaire. L'objectif de ce travail est de donner aux ingénieurs amenés à concevoir des convertisseurs une méthode capable de prédire les niveaux d'émissions conduites générées par un convertisseur électronique de puissance qui intègre des composants en SiC. La nouveauté du travail présenté dans cette thèse est l’intégration de différents modèles de type circuit pour tous les constituants d’un convertisseur (un hacheur série est pris comme exemple). Le modèle est valable pour une gamme de fréquences de 40Hz à 30MHz. Des approches de modélisation des parties passives du convertisseur sont présentées. Ces approches sont différentes selon que les composants modélisés soient disponibles ou à concevoir : elles sont basées sur des mesures pour la charge et les capacités ; elles sont basées sur des simulations prédictives pour routage du convertisseur. Le modèle complet du convertisseur (éléments passifs et actifs) est utilisé en simulation pour prédire les émissions conduites reçues dans le réseau stabilisateur d’impédance de ligne. Le modèle est capable de prédire l'impact de différents paramètres comme le routage, les paramètres de contrôle comme les différents rapports cycliques et les résistances de grille avec des résultats satisfaisants dans les domaines temporels et fréquentiels. Les résultats obtenus montrent que le modèle peut prédire les perturbations en mode conduit pour les différents cas jusqu'à une fréquence de 15MHz. Finalement, une étude paramétrique du convertisseur a été élaborée. Cette étude a permis de voir l’influence de la qualité des différents modèles comme les éléments parasites du routage, des composants passifs et actifs et d'identifier les éléments qui ont besoin d’un modèle précis pour avoir des résultats valides dans la prédiction des perturbations conduitesThe recent technological progress of semiconductors and increasing demand for power electronic converters in the different domains of electric energy particularly for applications in aeronautics and networks of transport and distribution impose new specifications such as high frequencies, high voltages, high temperatures and high current densities. All of this contributes in the strong development of SiC (Silicon Carbide) components. However these components create new issues in Electromagnetic Compatibility (EMC) because of the conditions of high frequency switching and high commutation speeds (high di/dt and dv/dt) compared to other conventional components in power electronics. A precise study of the emissions generated by SiC components is therefore necessary. The aim of this work is to give a method able to predict levels of conducted emissions generated by a power electronics converter with SiC components to engineers which design power converters. The novelty of the work presented in this thesis is the integration of different modeling approaches to form a circuit model of a SiC-based converter (a buck dc–dc converter is considered as an example). The modeling approach is validated in the frequency range from 40Hz to 30MHz. Modeling approaches of the passive parts of the converter are presented. Theses approaches differs according to whether the component is existing or to be designed : they are based on measurements for the load and capacitors; they are based on numerical computation and analytical formulations for PCB. The complete model obtained (passive and active components) is used in simulations to predict the conducted emissions received by the line impedance stabilization network. The model is able to predict the impact of various parameters such as PCB routing, the control parameters like duty cycles and different gate resistors in the time and frequency domains. A good agreement is obtained in all cases up to a frequency of 15MHz. Finally, a parametric study of the converter has been elaborated. This study allowed to see the influence of different models such as parasitic elements of the PCB, passive and active components and to identify the elements that need a precise model to obtain valid results in the prediction of conducted EMI
7
Pringle, Matthew. "Fnite [sic] element modelling of two-component, solid-liquid mixtures /." *McMaster only, 2001.
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8
Starec, Stanislav. "Akumulátorový svařovací zdroj." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2019. http://www.nusl.cz/ntk/nusl-399544.
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This master thesis is focused on proposition and following implementation of DC arc welder. This paper is based on semester’s paper, where the first version was realized. The welder is powered by a battery pack with LiFePO4 type cells. Battery cells are protected by BMS circuits. The driving electronics controls the duty cycle step-down (buck) converter in a closed current or power regulation loop. The power regulator has been designed and validated by simulations. Switching power transistors, low side and high side, are implemented by optically isolated gate drivers. Charging the battery is solved by a switching flyback converter. For the charger and the welder is sheet metal construction made of aluminum sheet.
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Mackichan, Calum. "Organization of secretion components in bacillus subtilis." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112122.
Повний текст джерелаАнотація:
La membrane bactérienne a fait l'objet de nombreuses études de localisation de protéines et de phospholipides. Par fusion d’une protéine fluorescente (GFP) aux gènes d’intérêt, il est alors possible d‘observer la localisation des protéines associées par microscopie. La plupart de ces observations ont été réalisées à l’aide de microscopes dits à épifluorescence. Afin d’obtenir une qualité d’image suffisante, il était nécessaire de surexprimer la protéine observée, insérée à un locus ectopique non naturel. Ce travail de thèse a permis d’utiliser une nouvelle technologie acquise dans notre laboratoire, le microscope à fluorescence par réflexion totale interne (TIRFM), plus puissant que le microscope à épifluorescence utilisé précédemment. Cette technologie a permis une caractérisation plus détaillée de la localisation de protéines d’intérêt, placées sous contrôle de leur promoteur naturel. Il a également été possible de caractériser la dynamique des foci observés. Nous avons concentré notre étude sur 3 protéines: (i) SecA pour l’étude de la translocation des protéines du cytoplasme vers la membrane, (ii) YidC pour l’insertion des protéines dans la membrane, (iii) PgsA pour la synthèse des phospholipids. Les foci se déplacent dynamiquement et s’associent de manière transitoire dans la membrane. L’observation sur la durée de ces foci, et l’analyse de leur intensité moyenne au cours des observations, montre que SecA se déplace sur l’ensemble de la membrane de manière uniforme. L’analyse du déplacement des foci montre une relation quadratique entre la distance moyenne parcourue par les foci en fonction du temps. Ce résultat est en accord avec l’hypothèse d’un mouvement brownien des foci. Les foci sont observés dans les différentes phases de croissance des cellules, et le nombre de foci présents dans une cellule de la longueur de celle-ci. SecA-GFP a été testés dans un certain nombre de contextes génétiques. La localisation a été perturbée lors de la déplétion de pgsA. Cependant, comme PgsA est une protéine essentielle, il ne peut être exclu que ce changement de localisation apparaît des cellules qui sont mortes ou mourantes. Dans une souche mutante ΔclsA, on n’observe aucune différence dans la localisation de SecA en phase exponentielle, mais on aperçoit une relocalisation aux poles en phase stationnaire de croissance. La voie Tat est responsable du transport des protéines devant être exportées dans un état structuré, par exemple dans le cas de l’incorporation d’un co-facteur. À ce jour, la régulation du système Tat est peu connues, de même que les interactions entre les différentes sous-unités du système Tat et d'autres protéines dans le cytoplasme, dans la membrane ou dans la paroi cellulaire. Des fusions de les gènes de la voie Tat ont été co-exprimées deux à deux dans des cellules de levure, et leur capacité à interagir in vivo a été testée par la méthode dite du double hybride chez la levure. Nous avons généré un réseau d’interaction autour des cinq composants de système Tat. Pour déterminer les implications fonctionnelles des composants du réseau, nous avons travaillé en collaboration avec le laboratoire de Jan-Maarten van Dijl. Nous avons utilisé une collection de souches mutantes pour lesquels certains composants individuels du réseau ont été retires. Trois a été observe d’etre nécessaires pour la sécrétion Tat-dépendante. Nous avons étudié la localisation des fusions GFP avec ces proteins. On a observé une localisation double de HemAT selon l’état physiologique de la cellule. En phase exponentielle, les cellules de B. subtilis sont généralement présentes sous forme de chaînes dans lesquelles le septum de division a déjà été formé, mais la séparation cellulaire n'a pas encore eu lieu. Une fusion de la GFP à CsbC apparaît de façon homogène dans la membraneIn the years since the cloning of GFP, the field of bacterial cell biology has characterized a variety of specific protein localization patterns in the bacterial membrane. The vast majority of early subcellular localization studies made use of inducible GFP fusions, which generally required the presence of high concentrations of inducer, and can therefore be considered to be overexpressed. An outstanding question remains over the organization of natively expressed proteins in the membrane. Here, we have investigated the localization of functional GFP fusions to proteins catalyzing important membrane processes; the secretion motor protein SecA, the membrane insertase YidC1, and the essential phospholipid synthase PgsA using total internal reflection fluorescence microscopy (TIRFM). This allowed natively expressed proteins to be localized with temporal resolution that can capture their dynamics. We characterized dynamic complexes dispersed throughout the membrane displaying diffusive movement with no preferred trajectories. Further characterization focused upon identifying conditions in which the localization pattern was disturbed. A polar mislocalization was identified in a cardiolipin mutant strain. The yeast two-hybrid (Y2H) approach is a robust approach to detect binary interactions on a proteome-scale. We performed genome-wide Y2H screens as well as targeted Y2H analyses for specific interactions involving components of the Sec and Tat secretion machineries of B. subtilis, revealing an intricate protein-protein interaction network involving 71 proteins. Furthermore, three proteins identified in the Tat network, WprA, CsbC and HemAT, were shown to be important for effective protein secretion via the B. subtilis Tat system, indicating that our yeast two hybrid assays reveal biologically significant interactions involving membrane proteins. The studies provide a novel proteomic view on the interaction network of the secretion systems of B. subtilis
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Souza, Filho Moyses de. "A configura??o da educa??o f?sica no Instituto Federal de Educa??o, Ciencia e Tecnologia do Rio Grande do Norte IFRN: contexto e perspectivas atuais." Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/14465.
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Previous issue date: 2011-11-17Over time the Physical Education on IFRN has considered the sport as the only possibility of pedagogical action. In the purpose of investigating the aspects that determine this condition, this study aimed the context of physical education within the institutional framework and its current perspectives in the process of institutional transformation. In this sense, were addressed the following study questions: What political pedagogical aspects that influenced the context of Physical Education on IFRN and how the pedagogical experience on Mossoro s campus incorporated the perspectives of curricular proposals transformation for the High School and the theoretical changes of the Brazilian Physical Education. Methodologically the work was based on a qualitative approach characterized as a descriptive- comparative research. The technique of discourse analysis was employed in the speech of research collaborators having as categories of analysis the professional activities time in the institution; The ratio of official use of the assumptions to the pedagogical practice of Physical Education in IFRN; The sport in the education process of students and The Prospects of Physical Education in the current configuration of IFRN. The data analysis allowed us to infer that the theoretical methodology of pedagogical practice of Physical Education in IFRN need to be reformulated and that it is necessary a contextualization with the curricular principles of the political institutional pedagogical project and with the Curriculum Guidelines for Secondary Education. The teaching experience developed in the Mossoro s Campus was contextualized with the national curriculum guidelines for secondary education and the theoretical changes of the Brazilian Physical Education. We conclude that it is necessary a collective action of the group of teachers to transform the educational profile of Physical Education of IFRN, beyond the institutional support to be able to consolidate the physical education curriculum component in the current dimensions of society, human being, education, science, technology and work, proposed by the philosophical principles and epistemological political project of IFRN educational
Ao longo do tempo a Educa??o F?sica no IFRN tem considerado o esporte como ?nica possibilidade de a??o pedag?gica. No proposito de investigar os aspectos que determinaram tal condi??o, este trabalho objetivou analisar o contexto da Educa??o F?sica no ?mbito institucional e suas perspectivas atuais no processo de transforma??o institucional. Nesse sentido, foram abordadas as seguintes quest?es de estudo: Quais os aspectos politico pedag?gicos que influenciaram o contexto da Educa??o F?sica no IFRN e Como a experi?ncia pedag?gica no campus Mossor? se integrou ?s perspectivas de transforma??o curriculares propostas para o Ensino M?dio e as transforma??es te?ricas da Educa??o F?sica brasileira. No plano metodol?gico o trabalho fundamentou-se na abordagem qualitativa de investiga??o caracterizando-se como uma pesquisa descritivo-comparativa. A t?cnica de An?lise do Discurso foi empregada nas falas dos colaboradores da pesquisa tendo como categorias de an?lise o tempo de atua??o profissional na institui??o; A rela??o de aplica??o dos pressupostos oficiais com a pr?tica pedag?gica da Educa??o F?sica no IFRN; O esporte no processo de forma??o dos educandos e As perspectivas da Educa??o F?sica na atual configura??o do IFRN. A an?lise dos dados nos possibilitou inferir que os pressupostos te?ricos metodol?gicos da pratica pedag?gica da Educa??o F?sica no IFRN precisam ser reformulados e que se faz necess?rio a sua contextualiza??o com os princ?pios curriculares do projeto pol?tico pedag?gico institucional e com as Orienta??es Curriculares para o Ensino M?dio. A experi?ncia pedag?gica desenvolvida no Campus Mossor? esteve contextualizada com as diretrizes curriculares nacionais para o Ensino M?dio e com as transforma??es te?ricas da Educa??o F?sica brasileira. Conclu?mos que se faz necess?rio uma a??o coletiva do grupo de professores para transformar o perfil pedag?gico da Educa??o F?sica do IFRN al?m do respaldo institucional para que seja poss?vel consolidar a Educa??o F?sica como componente curricular nas atuais dimens?es de sociedade, ser humano, educa??o, ci?ncia, tecnologia e trabalho propostos pelos princ?pios filos?ficos e epistemol?gicos do Projeto pol?tico pedag?gico do IFRN
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Lai, Rixin. "Analysis and Design for a High Power Density Three-Phase AC Converter Using SiC Devices." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/30155.
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The development of high power density three-phase ac converter has been a hot topic in power electronics area due to the increasing needs in applications like electric vehicle, aircraft and aerospace, where light weight and/or low volume is usually a must. Many challenges exist due to the complicated correlations in a three-phase power converter system. In addition, with the emerging SiC device technology the operating frequency of the converter can be potentially pushed to the range from tens of kHz to hundreds of kHz at higher voltage and higher power conditions. The extended frequency range brings opportunities to further improve the power density of the converter. Technologies based on existing devices need to be revisited.
In this dissertation, a systematic methodology to analyze and design the high power density three-phase ac converter is developed. All the key factors of the converter design are explored from the high density standpoint. Firstly, the criteria for the passive filter selection are derived and the relationship between the switching frequency and the size of the EMI filter is investigated. A function integration concept as well as the physical design approach is proposed. Secondly, a topology evaluation method is presented, which provides the insight into the relationships between the system constraints, operating conditions and design variables. Four topologies are then compared with the proposed approach culminating with a favored topology under the given conditions. Thirdly, a novel average model is developed for the selected topology, and used for devising a carrier-based control approach with simple calculation and good regulation performance. Fourthly, the converter failure mode operation and corresponding protection approaches are discussed and developed. Finally, a 10 kW three-phase ac/ac converter is built with the SiC devices. All the key concepts and ideas developed in this work are implemented in this hardware system and then verified by the experimental results.Ph. D.
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Chowdhury, Tondra Farhana. "Investigation and forecasting drift component of a gas sensor." Thesis, Linköpings universitet, Statistik och maskininlärning, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-172890.
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Chemical sensor based systems that are used for detection, identification, or quantification of various gases are very complex in nature. Sensor response data collected as a multivariate time series signals encounters gradual change of the sensor characteristics(known as sensor drift) due to several reasons. In this thesis, drift component of a silicon carbide Field-Effect Transistor (SiC-FET) sensor data was analyzed using time series. The data was collected from an experiment measuring output response of the sensor with respect to gases emitted by certain experimental object at different temperatures. Augmented Dickey Fuller Test (ADF) was carried out to analyze the sensor drift which revealed that stochastic trend along with deterministic trend characterized the drift components of the sensor. The drift started to rise in daily measurements which contributed to the total drift.Traditional Autoregressive Integrated Moving Average (ARIMA) and deep learning based Long Short-Term Memory (LSTM) algorithm were carried out to forecast the sensor drift in reduced set of data. However, reduction of the data size degraded the forecasting accuracy and imposed loss of information. Therefore, careful selection of data using only one temperature from the temperature cycle was chosen instead of all time points. This chosen data from sensor array outperformed forecasting of sensor drift than reduced dataset using both traditional and deep learning methods.
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Huang, Runhua. "Conception, suivi de fabrication et caractérisation électrique de composants haute tension en SiC." Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00708553.
Повний текст джерелаАнотація:
Les composants actifs en électronique de puissance sont principalement à base de Silicium. Or, le silicium a des limites en termes de température d'utilisation, fréquence de commutation et de tenue en tension. Une alternative au Si peut être les semi-conducteurs à grand gap tels que le SiC-4H. Grâce aux travaux de plusieurs équipes de chercheurs dans le monde, les performances s'améliorent d'année en année. Le laboratoire AMPERE conçoit, réalise et caractérise des composants de puissance en SiC-4 H. Cette thèse s'inscrit dans les projets SiCHT2 et VHVD du laboratoire. Le travail réalisé au cours de cette thèse repose sur la conception la fabrication et la caractérisation électrique de composantes haute tension en SiC-4H. Les paramètres de protection pour la diode bipolaire 6500V sont optimisés à l'aide des simulations à base d'éléments finis. Les paramètres du SiC pour les modèles utilisés pour la simulation sont développés par des travaux précédents. Ensuite, le masque est dessiné. La diode est réalisée chez IBS. La première caractérisation est effectuée avant le recuit post-métallisation en directe et inverse sans passivation finale. Après le recuit post-métallisation la résistance de contact est plus faible. La caractérisation de la tenue en tension a été effectuée à AMPERE puis à l'ISL à très haute tension. A l'aide de simulations à base d'éléments finis, les paramètres tels que la résistance de contact et la durée de vie des porteurs ont été affinés à partir des caractérisations électriques obtenues par l'expérience. Les autres travaux portent sur la conception, les optimisations et les fabrications des diodes 10 kV et transistors 6500 V.
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Crosara, Flávia de Sousa Gomes. "Influência do peso dos ovos de reprodutoras Leghorn sobre as características dos ovos incubáveis e dos pintos de um dia." Universidade Federal de Uberlândia, 2013. https://repositorio.ufu.br/handle/123456789/13070.
Повний текст джерелаАнотація:
The weight´s effect on egg´s quality, performance characteristics and incubation of chicks were observed in two experiments. Three treatments were used, defined by the weight of the eggs, breeding Leghorn 38 weeks old: small (S) 53 to 57g, medium (M) 58 to 62g and large (L) 63 to 67g. We have evaluated: a) the eggs - strength and shell thickness, Haugh units (HU), albumen height and percentage of egg compounds b) in incubation - eggs weight loss , hatching and embryo diagnosis, c) in one day old chicks in the yolk sac: weight and length of the chick, absolute and relative weight of the yolk sac, d) dry material (DM), crude protein (CP) albumen´s energy , and the yolk sac. Eggs range of different weights produced by Leghorn breeders of the same age (38 weeks) did not show differences among them for shelll strength, relative weight of albumen and yolk, albumen and yolk in DM and gross energy in the yolk. There are differences in the shell thickness, UH, albumen height, absolute weight of egg components, the relative weight of shell, the yolk and albumen protein and gross energy albumen. In the incubation, the weight loss of eggs and the hatch decreases with increasing egg weight range. Unhatched eggs increase with the increase of initial mortality and pecked alive and dead. The chick weight, absolute and relative weight of the yolk sac are directly proportional to the weight of the egg. The proportion of protein in the yolk sac decreases with increasing egg weight and gross energy content is higher in the yolk sac of chicks hatched from medium eggs.Os efeitos do peso do ovo sobre a qualidade dos ovos, rendimento de incubação e características dos pintos foram avaliados, em dois experimentos. Foram utilizados três tratamentos definidos pela faixa de peso dos ovos de reprodutoras Leghorn, da linhagem Dekalb White, com 38 semanas de idade: pequeno (P) de 53 a 57g, médio (M) de 58 a 62g e grande (G) 63 a 67g. Avaliou-se: a) nos ovos: resistência e espessura da casca, unidades Haugh (UH), altura de albúmen e porcentagem dos seus componentes; b) na incubação: perda de peso dos ovos, eclosão e embriodiagnóstico; c) nos pintos de um dia e no saco vitelino: peso e comprimento do pinto, peso absoluto e relativo do saco vitelino; d) matéria seca (MS), proteína bruta (PB) e energia bruta do albúmen, gema e saco vitelino. Ovos de faixa de pesos diferentes produzidos por reprodutoras Leghorn de mesma idade (38 semanas) não demonstram diferenças entre si para resistência da casca, peso relativo do albúmen e da gema, MS no albúmen e gema e energia bruta na gema. As diferenças residem na espessura da casca, UH, altura do albúmen, peso absoluto dos componentes dos ovos, peso relativo da casca, na PB da gema e albúmen e na energia bruta do albúmen. Na incubação, a perda de peso dos ovos e a eclosão diminuem com o aumento da faixa de peso dos ovos. Ovos não eclodidos aumentam em função do aumento da mortalidade inicial e bicados vivos e mortos. O peso do pinto, peso relativo e absoluto do saco vitelino são diretamente proporcionais ao peso do ovo. A percentagem de PB no saco vitelino diminui com o aumento do peso dos ovos e o teor de energia bruta é maior no saco vitelino de pintos nascidos de ovos médios.
Mestre em Ciências Veterinárias
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Facco, Alexandro Gomes. "Modelagem e simulação geoespacial dos componentes do balanço hídrico para plantios de eucalipto em áreas de relevo ondulado." Universidade Federal de Viçosa, 2004. http://www.locus.ufv.br/handle/123456789/8147.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Este trabalho tem como objetivo geral estimar o balanço hídrico do solo, levando em consideração a redistribuição de água e de energia solar em função da exposição do terreno em plantios florestais de eucalipto. Especificamente, visa desenvolver um sistema computacional capaz de estimar os diferentes componentes do balanço hídrico do solo para diferentes áreas de plantios de eucalipto em áreas de relevo ondulado, e determinar a influência da topografia no saldo de radiação e, conseqüentemente, na evapotranspiração. O estudo foi realizado em uma micro-bacia hidrográfica do rio Doce, com área de 364 ha, pertencente à empresa “Celulose Nipo-Brasileira S.A. (CENIBRA)”, que possuí eucaliptos plantados nos anos de 1998 e 1999. A micro-bacia está localizada no município de Belo Oriente, região do Vale do Rio Doce, estado de Minas Gerais, com coordenadas geográficas centrais de latitude 19o 21’ S e longitude 42o 15’ O. A topografia é de plana a forte ondulada, com altitude média de 248 m e inclinação média de 21%. As encostas têm orientações predominantes com faces voltadas para sul e sudeste. O modelo de balanço de água no solo para determinado dia foi descrito pelo armazenamento de água no solo no dia anterior, somando-se os componentes de entrada (precipitação, escoamento superficial) e componentes de saída (interceptação da água da chuva pelo dossel, interceptação de água pela serapilheira, evapotranspiração, escoamento superficial e percolação profunda). Verificou-se existir influências das diferentes inclinações e orientações das encostas nos totais diários de evapotranspiração. De uma forma geral, este fato está relacionado com à maior ou menor disponibilidade de energia para o processo de mudança de fase da água, que depende da face de exposição do terreno e da elevação solar. A interceptação da água da chuva pela cobertura vegetal variou em função da idade da planta, do total precipitado e da distribuição da precipitação. Ao determinar a disponibilidade de água na camada útil do solo, verificou-se existir importantes contribuições de água proveniente das camadas inferiores a camada útil do solo. No ano de 2001, nas áreas com plantios de 2 anos de idade, foram registrados valores médios de aporte mínimo de água das camadas mais profundas para camada útil do solo, de 261 mm, e nas áreas com plantios de 3 anos de idade, 242 mm. Neste ano ainda, ocorreram excessos médios de 192 mm nas áreas cm plantios de 2 anos de idade e de 148 mm nas áreas com plantios de 3 anos. Em nenhum dia, dos 2 anos de estudos, foi registrado escoamento superficial. Verifica-se, portanto ser importante, em regiões de relevo ondulado, fazer a correção espacialmente da intensidade de fluxo da irradiância solar medida no piranômetro. Embora muitos parâmetros usados para a determinação do balanço hídrico precisem ser melhorados, para as condições de plantio de eucalipto, este estudo propõe uma excelente perspectiva para estimar a disponibilidade de água e energia para planta e, conseqüentemente, a influência destes fatores no seu desenvolvimento.
The Overall goal of this study was to estimate of the soil water balance in consideration of water and solar energy redistribution on account of the terrain exposition function in forest eucalypt culture; specific objective was the development of a computer system that would be able to estimate the different components of the soil water balance for different eucalypt culture areas with an undulated relief and to determine the topographic influence on the radiation balance and, consequently, on evapotranspiration. The study was carried out in the Rio Doce micro-watershed, covering a 364 ha area of the company “Celulose Nipo-Brasileira S.A. (CENIBRA)” with eucalypt cultures planted in 1998 and 1999. The micro-watershed lies in the county of Belo Oriente, Vale do Rio Doce region , State of Minas Gerais (center at 19o 21’ S latitude and 42o 15’ W longitude). The topography is plain to strongly undulate, at a mean height of 248 m and with a mean slope of 21%. Predominantly, the ramp surfaces face South and Southeast. The soil water balance model determined any particular day as follows: soil water storage of the previous day plus the entry (precipitation and runoff) and minus the escape components (rainwater interception by the canopy and organic layer, evapotranspiration, runoff, and profound drainage). Influence of the different inclinations and ramp orientations on the daily total of evapotranspiration was confirmed. In general, this fact is related to the higher or lower energy availability for the process of change of the water phase, which depends on the face of terrain exposition and solar elevation. Rain water interception by the plant coverage varied according to plant age, total precipitation, and precipitation distribution. At determining the water availability in the root soil layer, important contributions of water through inferior layers were observed. In 2001, areas with 2 year-old cultures received mean values of minimum water input from the deepest to the useful soil layer of 216 mm, while areas with 3-year-old cultures received 242 mm. In the same year, mean excesses of 192 mm occurred in the areas with two-year- old cultures and 148 mm in the areas with three-year-old cultures. Runoff was not registered once in the two study years. Therefore, it can affirm that in regions of undulate relief, a spatial correction of the solar radiation intensity measured by a pyranometer would be important. Though many parameters used to determine the water balance need improvement for the conditions of eucalypt culture, this study proposes an excellent perspective to estimate water and energy availability to the plant and, consequently, the influence of these factors on its development.
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Na, Bing. "Structure and Function of Escherichia Coli Seca: An Essential Component of the Sec Translocase." restricted, 2007. http://etd.gsu.edu/theses/available/etd-08092007-163142/.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Georgia State University, 2007.Title from file title page. Phang C. Tai, committee chair; John Houghton Parjit Kaur, Chung-Dar Lu, committee members. Electronic text (148 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Dec. 7, 2007. Includes bibliographical references (p. 125-140).
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Cranford-Smith, Tamar. "Genetic, biochemical and structural characterisation of YecA, a novel component of the bacterial Sec machinery." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8354/.
Повний текст джерелаАнотація:
The Sec pathway provides a mechanism for the translocation of proteins across or into the cytoplasmic membrane. In bacteria, SecA is a core component of the Sec machinery. YecA has a 20-amino acid sequence at its carboxy-terminus that has high sequence identity to the zinc-binding domain at the carboxy-terminus of SecA. This study provides evidence to show that YecA is a novel component of the Sec machinery of E. coli. The yecA gene is not essential for the viability of E. coli but the deletion of yecA interferes with Sec-dependent translocation and the combined deletion of the yecA and secB genes results in a severely cold-sensitive phenotype. The genetic investigations were supported by biochemical evidence that suggests that YecA improves the translocation-coupled ATPase activity of SecA. Structural investigations suggest that YecA is a monomer in solution. The α-helical domain that forms the main body of YecA is connected via a short linker with limited flexibility to an independent metal-binding domain that has two conformations. The purification of YecA suggested the presence of iron. Biophysical experiments were used to confirm the interaction of the YecA metal-binding domain with iron. This study provides evidence for an additional component of the translocation machinery.
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Silva, Anderson Paz da. "Diversidade de comunidades de pequenos mamíferos de três fitofisonomias [sic] do Cerrado no Brasil Central : partição da diversidade regional em componentes alfa e beta." reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/13606.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Ecologia, Programa de Pós-Graduação em Ecologia, 2013.Submitted by Luiza Silva Almeida (luizaalmeida@bce.unb.br) on 2013-07-16T16:58:40Z No. of bitstreams: 1 2013_AndersonPazdaSilva.pdf: 1300394 bytes, checksum: 55a04f946044a5964781bc9654815af8 (MD5)
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A diversidade de grupos animais pode estar relacionada à heterogeneidade e/ou à complexidade do ambiente. No domínio vegetacional Cerrado, a alta diversidade de pequenos mamíferos tem sido atribuída à heterogeneidade ambiental e a influência da complexidade ainda é uma questão aberta. O objetivo deste trabalho foi avaliar a partição da diversidade de pequenos mamíferos de uma região de Cerrado do Brasil Central em áreas de vegetação savânica típica – cerrado sensu stricto (cerrado s.s.) – e de formações florestais – cerradão e mata de galeria – considerando os efeitos da complexidade ambiental. A riqueza de espécies e os índices de diversidade “verdadeira” de Shannon e Simpson foram as métricas de diversidade usadas. Amostrei quatro áreas de cada fitofisionomia dispondo armadilhas no solo e sub-bosque nas três formações e também no dossel em cerradão e mata. Com esforço amostral total de 15744 armadilhas-noite em todo o estudo, capturei 348 indivíduos de 14 espécies. A amostragem de dossel em mata e cerradão incrementou suas riquezas de espécies, indicando efeito positivo da complexidade ambiental na maior riqueza dessas formações em relação a cerrado s.s.. Houve efeito da abundância das espécies nos padrões de diversidade das fitofisionomias. A mata teve maior diversidade do que cerradão e cerrado s.s. e estes não diferiram entre si pelo índice de Shannon. Já pelo índice de Simpson, mata teve maior diversidade, seguida por cerrado s.s. e por cerradão. Comunidades de cerradão tiveram similaridade de composição intermediária entre cerrado s.s. e mata de galeria, compartilhando espécies destas duas fitofisionomias. A diversidade beta entre fitofisionomias foi o componente com maior contribuição na diversidade regional, ao se considerar a riqueza e o índice de Shannon. No entanto, ela não diferiu do esperado pelo índice de Simpson, devido a uma mesma espécie ter sido a mais abundante em todas fitofisionomias. Por outro lado, o turnover de espécies entre comunidades de uma mesma fitofisionomia foi baixo (0,23) e entre fitofisionomias foi baixo/moderado (0,38), indicando pouco efeito da diversidade de fitofisionomias na diversidade de pequenos mamíferos no estudo. O presente estudo mostra a importância da amostragem de dossel de formações florestais e da consideração de múltiplas áreas de diferentes fitofisionomias em estudos de diversidade de pequenos mamíferos e traz informações que podem contribuir para a conservação de áreas do Cerrado, especialmente de cerradão. ______________________________________________________________________________ ABSTRACT
The diversity of animal groups may be related to the heterogeneity and/or to the environmental complexity. In the Cerrado domain, the high diversity level of small mammals has been related to the environmental heterogeneity and the influence of environmental complexity is still an open topic. The purpose of this study was to evaluate the partition of small-mammal diversity from a Cerrado region in central Brazil in areas of typical savannah – cerrado sensu stricto (cerrado s.s.) – and areas of forest vegetation – woodland savannah and gallery forest – considering the effects of the environmental complexity. The species richness and the Shannon’s and Simpson’s true diversity indexes were the diversity metrics used in the study. I selected four areas of each phytophysiognomic formation and trapped individuals on the ground and in the understorey levels at all phytophysiognomic formations. Additionally I also trapped individuals in the canopy at woodland savannahs and gallery forests. A total of 348 individuals of 14 species was caught in 15744 trap-nights all over the study. The trapping in the canopy of gallery forests and woodland savannahs increased the species richness, thus indicating a positive effect of the environmental complexity in the higher richness level of these formations compared to cerrado s.s. There was a marked effect of species abundance on the diversity patterns of the physiognomies. Gallery forest had higher diversity level than woodland savannah and cerrado s.s. and these two formations did not differ from each other considering the Shannon index. However, considering the Simpson index, gallery forest had the higher diversity level, followed by cerrado s.s. and after by woodland savannah. Woodland savannah areas had an intermediary compositional similarity with areas of cerrado s.s. and areas of gallery forest, harboring species of these formations. The beta diversity between physiognomies was the main component driving the regional diversity regarding richness of species and the Shannon index. However, considering the Simpson index this beta diversity did not differ from the expected values due to the fact that a single species was the most abundant in all the physiognomies. The turnover of species between communities was low (0,23) and it was low/moderate (0,38) between physiognomies. These results indicate that environmental heterogeneity has a minor effect on the small mammals diversity in the study. This study shows the importance of trapping small mammals in the canopy and of considering multiple areas of different physiognomies in studies of small mammals diversity and provides some information that may be applied for the conservation of Cerrado’s areas, specially the woodland savannahs.
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Ara?jo, Juliany de Souza. "Efeitos do destreinamento em componentes da aptid?o f?sica de pessoas vivendo com HIV/AIDS." PROGRAMA DE P?S-GRADUA??O EM EDUCA??O F?SICA, 2017. https://repositorio.ufrn.br/jspui/handle/123456789/23611.
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O objetivo do estudo foi avaliar o efeito do destreinamento em componentes da aptid?o f?sica de pessoas vivendo com HIV/Aids (PVHA). O estudo foi de car?ter experimental com amostra composta por Grupo Experimental (GE) com 11 PVHA, sob terapia antiretroviral e Grupo Controle (GC) com 10 sem a infe??o; todos com libera??o m?dica e insuficientemente ativos. Avaliou-se a composi??o corporal pelo DEXA, aptid?o cardiorrespirat?ria pelo Ergoespir?metro e for?a de membros superiores e inferiores por dinamometria. Ambos os grupos realizaram interven??o com treinamento concorrente por 15 semanas e foi avaliado o destreinamento ap?s 5 semanas. Ap?s a an?lise de normalidade dos dados pelo teste de Shapiro Wilk foi utilizado, na estat?stica inferencial, o teste Wilcoxon para avaliar diferen?a entre os par?metros avaliados antes e ap?s o tempo de destreino. Resultados apontaram diferen?a significativa nos limiares 1, 2,VO2 pico e na for?a de membros inferiores no GE, enquanto no GC apresentaram apenas no limiar 2 e VO2 pico. Conclu?mos que dentre os componentes da aptid?o f?sica o destreinamento, promoveu maiores efeitos delet?rios na capacidade cardiorrespirat?ria e na for?a muscular de PVHA. J? na composi??o corporal o efeito do destreino foi semelhante nos grupos, sendo observado piora em alguns componentes. Enfatizamos, que a suspen??o de programas de treinamentos com exerc?cios f?sicos deva ser evitada, a fim de minimizar os preju?zos causados pela inatividade f?sica e efeitos adversos do v?rus HIV e terapia, que tornam PVHA suscept?veis as doen?as cardiovasculares.
O objetivo do estudo foi avaliar o efeito do destreinamento em componentes da aptid?o f?sica de pessoas vivendo com HIV/Aids (PVHA). O estudo foi de car?ter experimental com amostra composta por Grupo Experimental (GE) com 11 PVHA, sob terapia antiretroviral e Grupo Controle (GC) com 10 sem a infe??o; todos com libera??o m?dica e insuficientemente ativos. Avaliou-se a composi??o corporal pelo DEXA, aptid?o cardiorrespirat?ria pelo Ergoespir?metro e for?a de membros superiores e inferiores por dinamometria. Ambos os grupos realizaram interven??o com treinamento concorrente por 15 semanas e foi avaliado o destreinamento ap?s 5 semanas. Ap?s a an?lise de normalidade dos dados pelo teste de Shapiro Wilk foi utilizado, na estat?stica inferencial, o teste Wilcoxon para avaliar diferen?a entre os par?metros avaliados antes e ap?s o tempo de destreino. Resultados apontaram diferen?a significativa nos limiares 1, 2,VO2 pico e na for?a de membros inferiores no GE, enquanto no GC apresentaram apenas no limiar 2 e VO2 pico. Conclu?mos que dentre os componentes da aptid?o f?sica o destreinamento, promoveu maiores efeitos delet?rios na capacidade cardiorrespirat?ria e na for?a muscular de PVHA. J? na composi??o corporal o efeito do destreino foi semelhante nos grupos, sendo observado piora em alguns componentes. Enfatizamos, que a suspen??o de programas de treinamentos com exerc?cios f?sicos deva ser evitada, a fim de minimizar os preju?zos causados pela inatividade f?sica e efeitos adversos do v?rus HIV e terapia, que tornam PVHA suscept?veis as doen?as cardiovasculares.
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Mazariegos, Mario Rolando. "Biogenesis of basement membrane components by the endodermal cells of the rat parietal yolk sac as studied by radioautography." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66113.
Повний текст джерела
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Bauman, Lara Elizabeth. "QTL variance component models." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1464110531&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
Повний текст джерела
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Hamieh, Youness. "Caractérisation et modélisation du transistor JFET en SiC à haute température." Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00665817.
Повний текст джерелаАнотація:
Dans le domaine de l'électronique de puissance, les dispositifs en carbure de silicium (SiC) sont bien adaptés pour fonctionner dans des environnements à haute température, haute puissance, haute tension et haute radiation. Le carbure de silicium (SiC) est un matériau semi-conducteur à large bande d'énergie interdite. Ce matériau possède des caractéristiques en température et une tenue aux champs électriques bien supérieure à celles de silicium. Ces caractéristiques permettent des améliorations significatives dans une grande variété d'applications et de systèmes. Parmi les interrupteurs existants, le JFET en SiC est l'interrupteur le plus avancé dans son développement technologique, et il est au stade de la pré-commercialisation. Le travail réalisé au cours de cette thèse consiste à caractériser électriquement des JFET- SiC de SiCED en fonction de la température (25°C-300°C). Des mesures ont été réalisé en statique (courant-tension), en dynamique (capacité-tension) et en commutation sur charge R-L (résistive-inductives) et dans un bras d'onduleur. Un modèle multi-physique du transistor VJFET de SiCED à un canal latéral a été présenté. Le modèle a été développé en langage MAST et validé aussi bien en mode de fonctionnement statique que dynamique en utilisant le simulateur SABER. Ce modèle inclut une représentation asymétrique du canal latéral et les capacités de jonction de la structure. La validation du modèle montre une bonne concordance entre les mesures et la simulation.
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Schmitt, Rafael Eduardo. "Acad?micos de educa??o f?sica : perfil, motiva??es e o valor atribu?do aos componentes formativos." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2011. http://tede2.pucrs.br/tede2/handle/tede/3670.
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Previous issue date: 2011-01-14O estudo, de car?ter explorat?rio-descritivo e baseado nos m?todos quantitativos, analisa o valor atribu?do por acad?micos de Educa??o F?sica para diversas ?reas de estudo que comp?em sua forma??o acad?mica, al?m de identificar o perfil desses estudantes sob diversos aspectos. O embasamento te?rico fundamenta-se no contexto formativo da ?rea, a partir de uma perspectiva hist?rico-cr?tica, bem como, na tem?tica da motiva??o acad?mica, com base em teorias motivacionais contempor?neas e estudos realizados em contextos universit?rios. O campo de investiga??o compreendeu tr?s institui??es de ensino superior localizadas na regi?o metropolitana de Porto Alegre/RS. A amostra foi composta por 428 acad?micos dos cursos de Licenciatura e Bacharelado em Educa??o F?sica, provenientes da Pontif?cia Universidade Cat?lica do Rio Grande do Sul, da Universidade do Vale do Rio dos Sinos e da Universidade Federal do Rio Grande do Sul. A coleta de dados foi realizada a partir de um instrumento pr?prio, denominado Escala de Valoriza??o das ?reas de Estudo, o qual investigou a percep??o de import?ncia para 52 ?reas de estudo contidas no processo formativo. Os resultados, ao apontarem aspectos relacionados ao perfil dos estudantes, demonstraram concord?ncia com as tend?ncias hist?ricas observadas no campo da Educa??o F?sica, na qual as ?reas biol?gicas constituem-se como os componentes mais valorizados, em contraste com as ?reas humanas que demonstram ser as menos valorizadas. Considerando as ?reas de estudo investigadas, identificaram-se oito dimens?es formativas, segundo a percep??o dos acad?micos, as quais se agruparam por crit?rios de afinidade epistemol?gica. An?lises comparativas observaram expressivas variabilidades em fun??o do g?nero e das modalidades de curso, verificando que as mulheres atribuem maior valor aos estudos, mostram-se mais motivadas e apresentam maior dedica??o ?s atividades acad?micas, quando comparadas com os homens. Resultados semelhantes foram observados na compara??o entre licenciandos e bacharelandos. Entretanto, as maiores variabilidades ocorreram quando comparados estudantes com diferentes pretens?es de atua??o futura. As perspectivas futuras quanto ao campo de atua??o profissional demonstram ser um importante componente motivacional, que interfere no valor atribu?do ?s ?reas de estudo. As contribui??es proporcionadas buscam dialogar com a comunidade acad?mica da Educa??o F?sica, a qual necessita refletir sobre formas de revalorizar as ?reas humanas no interior dos curr?culos de forma??o.
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Abou, Hamad Valdemar. "Elaboration et caractérisation de contacts électriques à base de phases MAX sur SiC pour l'électronique haute température." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI079.
Повний текст джерелаАнотація:
Les applications de puissance dans lesquelles la température ambiante est élevée, provoquent l’augmentation de la température dans les dispositifs électroniques. De ce fait, il est important de développer les dispositifs électroniques pour pouvoir supporter des densités de courant et de puissance plus élevées. Dans cette thèse, nous avons pour objectif de jeter les bases d’une technologie en totale rupture avec celles existantes pour la fabrication d’une nouvelle génération de contacts électriques à base de Ti3SiC2, stables, fiables et reproductibles sur le Carbure de Silicium pour les applications à très hautes températures (300 – 600ºC). Deux méthodes d’élaborations seront étudiées, dans cette thèse, pour synthétiser le Ti3SiC2. La première est par voie réactionnelle, et la deuxième approche consistera à utiliser la technique Pulsed Laser Deposition (PLD), en utilisant une cible de Ti3SiC2. Le but est de développer des contacts ohmiques de bonne qualité. Des caractérisations physico-chimiques, électriques (TLM) et mécaniques (W-H et RSM) ont été effectuées sur les contacts de Ti3SiC2. Ces échantillons ont subi un vieillissement, à 600ºc pendant 1500h sous Argon, dans le but d’étudier la stabilité et la fiabilité des contacts électriques aux hautes températures. Les résultats des caractérisations ont montré que la fiabilité et la stabilité chimique entre Ti3SiC2 et SiC ont permis aux contacts de garder le comportement ohmique avec une faible résistivité électrique et un bon comportement mécanique, même après 1500h de vieillissement. De plus, les simulations réalisées ont servi à déterminer l’effet des ITR sur la dissipation de la chaleur et sur les contraintes mécaniques exercées sur une diode PN haute puissance. Dans cette thèse, nous avons montré qu’un contact ohmique, à base de Ti3SiC2, peut rester stable et fiable sur un substrat 4H-SiC, dans des températures allant jusqu’à 600ºCPower applications in which the ambient temperature is high, cause the increase of temperature in electronic components. Therefore, it is important to develop electronic devices that are able to withstand high current and high-power densities. In this thesis, our objective is to lay the foundations of a new technology for the manufacture of a new generation of Ti3SiC2 MAX phase-based electrical contacts, stable, reliable and reproducible on Silicon Carbide for very high temperature applications (300 - 600ºC). To synthesize Ti3SiC2 on SiC, two elaboration methods were studied in this thesis. The first approach is a reaction method, and the second approach consists on using a Ti3SiC2 target via the Pulsed Laser Deposition (PLD) technique. Our goal is to develop a good quality ohmic contacts. Physico-chemical, electrical (TLM) and mechanical (W-H and RSM) characterizations were performed on the Ti3SiC2 contacts. These samples underwent a thermal aging test at 600°C for 1500 hours under Argon, in order to study the stability and reliability of the electrical contacts at high temperatures. The obtained results showed that the reliability and the chemical stability between Ti3SiC2 and SiC allowed the contacts to keep an ohmic behavior with low electrical resistivity, in addition to a good mechanical behavior, even after 1500 hours of aging at 600ºC. Furthermore, the thermomechanical simulations performed were used to determine the effects of Interfacial Thermal Resistances on the heat dissipation and the mechanical stresses exerted on a high power PN diode. In this thesis, we have shown that an ohmic contact, based on Ti3SiC2, can remain stable and reliable on a 4H-SiC substrate, in temperatures up to 600ºC
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Jain, Gaurav. "Genomic comparison of species based on metabolic pathway components." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 61 p, 2008. http://proquest.umi.com/pqdweb?did=1605156451&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Повний текст джерелаАнотація:
Thesis (M.S.)--University of Delaware, 2008.Principal faculty advisors: Li Liao, Dept. of Computer & Information Sciences and E. Fidelma Boyd, Dept. of Biological Sciences. Includes bibliographical references.
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Alsup, Sarah. "Evaluation of metal leachability from green roof systems and components /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1797219561&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Storey, Nathaniel R. "An aquaponic system component comparisons and applications /." Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1939351881&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Carrillo, Rozo Oscar. "Formal and incremental verification of SysML for the design of component-based system." Thesis, Besançon, 2015. http://www.theses.fr/2015BESA2017/document.
Повний текст джерелаАнотація:
Vérification Formelle et Incrémentale de Spécifications SysML pour la Conception de Systèmes à Base de ComposantsLe travail présenté dans cette thèse est une contribution à la spécification et la vérification des Systèmes à Base de Composants (SBC) modélisé avec le langage SysML. Les SBC sont largement utilisés dans le domaine industrielet ils sont construits en assemblant différents composants réutilisables, permettant ainsi le développement de systèmes complexes en réduisant leur coût de développement. Malgré le succès de l'utilisation des SBC, leur conception est une étape de plus en plus complexe qui nécessite la mise en {\oe}uvre d'approches plus rigoureuses.Pour faciliter la communication entre les différentes parties impliquées dans le développement d'un SBC, un des langages largement utilisé est SysML, qui permet de modéliser, en plus de la structure et le comportement du système, aussi ses exigences. Il offre un standard de modélisation, spécification et documentation de systèmes, dans lequel il est possible de développer un système, partant d'un niveau abstrait, vers des niveaux plus détaillés pouvant aboutir à une implémentation. %Généralement ces systèmes sont faits plus grands parce qu'ils sont développés avec des cadres logiciels.Dans ce contexte nous avons traité principalement deux problématiques.La première est liée au développement par raffinement d'un SBC modélisé uniquement par ses interfaces SysML. Notre contribution permet au concepteur des SBC de garantir formellement qu'une composition d'un ensemble de composants élémentaires et réutilisables raffine une spécification abstraite d'un SBC. Dans cette contribution, nous exploitons les outils: Ptolemy pour la vérification de la compatibilité des composants assemblés, et l'outil MIO Workbench pour la vérification du raffinementLa deuxième problématique traitée concerne la difficulté de déterminer quoi construire et comment le construire, en considérant seulement les exigences du système et des composants réutilisables, donc la question qui en découle est la suivante: comment spécifier une architecture SBC qui satisfait toutes les exigences du système? Nous proposons une approche de vérification formelle incrémentale basée sur des modèles SysML et des automates d'interface pour guider, par les exigences, le concepteur SBC afin de définir une architecture de système cohérente, qui satisfait toutes les exigences SysML proposées. Dans cette approche nous exploitons le model-checker SPIN et la LTL pour spécifier et vérifier les exigences.Mots clés: {Modélisation, Spécifications SysML, Architecture SBC, Raffinement, Compatibilité, Exigences, Propriétés LTL, Promela/SPIN, Ptolemy, MIO Workbench}Formal and Incremental Verification of SysML Specifications for the Design of Component-Based SystemsThe work presented in this thesis is a contribution to the specification and verification of Component-Based Systems (CBS) modeled in SysML. CBS are widely used on the industrial field, and they are built by assembling various reusable components, allowing developing complex systems at lower cost.Despite the success of the use of CBS, their design is an increasingly complex step that requires the implementation of more rigorous approaches.To ease the communication between the various stakeholders in a CBS development project, one of the widely used modeling languages is SysML, which besides allowing modeling of structure and behavior, it has capabilities to model requirements. It offers a standard for modeling, specifying and documenting systems, wherein it is possible to develop a system, starting from an abstract level, to more detailed levels that may lead to an implementation.In this context, we have dealt mainly two issues. The first one concerns the development by refinement of a CBS, which is described only by its SysML interfaces and behavior protocols. Our contribution allows the designer of CBS to formally ensure that a composition of a set of elementary and reusable components refines an abstract specification of a CBS. In this contribution, we use the tools: Ptolemy for the verification of compatibility of the assembled components and MIO Workbench for refinement verification.The second one concerns the difficulty to decide what to build and how to build it, considering only system requirements and reusable components. Therefore, the question that arises is: how to specify a CBS architecture, which satisfies all system requirements? We propose a formal and incremental verification approach based on SysML models and interface automata to guide, by the requirements, the CBS designer to define a coherent system architecture that satisfies all proposed SysML requirements. In this approach we use the SPIN model-checker and LTL properties to specify and verify requirements.Keywords: {Modeling, SysML specifications, CBS architecture, Refinement, Compatibility, Requirements, LTL properties, Promela/SPIN, Ptolemy, MIO Workbench}
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Esposte, Júlio César. "Estudo comparativo de estrutura/propriedades da liga Al-Si5-Cu3-Mg nos estados fundido e tixoconformado, para utilização em componentes de motores." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263604.
Повний текст джерелаАнотація:
Orientador: Maria Helena RobertDissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica
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Resumo: Este trabalho teve como objetivo a análise comparativa entre a liga Al-Si5-Cu3-Mg nos estados fundido sob pressão (injetado) e tixoconformado, tomando-se como base um componente comercial suporte de acessórios utilizado em motores a diesel. Caracterizou-se o componente comercial produzido pelo processo de injeção em termos de estrutura e propriedades mecânicas, e por sua vez o produto final obtido pelo processo de tixoconformação é também caracterizado nos mesmos termos a fim de se obter uma base comparativa. Para análise da tixohabilidade, ou seja, capacidade de obtenção de pastas tixotrópicas da liga em estudo, submeteu-se a mesma a análises térmicas utilizando técnicas de DSC, e através de simulação termodinâmica utilizando software THERMOCALC®. São discutidas as temperaturas de transformação e intervalos de solidificação, sugerindo-se janelas de tixoconformação para a liga. A liga foi submetida a tratamentos térmicos de globularização de 120 e 300s, para duas condições de frações sólidas, 45 e 60%, além da avaliação da influência de uma pré-formação a frio por compressão do lingote antes da tixoconformação. A liga mostrou-se interessante para a produção de pastas tixotrópicas, com intervalo de solidificação na ordem de 100°C, além de uma variação da fração líquida com a temperatura favorável para definição da janela de tixoconformação. Este comportamento tixotrópico permitiu o total preenchimento do molde e a obtenção de produtos tixoconformados de boa qualidade, com destaque para a diminuição dos teores de porosidade em comparação aos apresentados pelo componente injetado (cerca de 17 vezes inferiores). O material submetido à prévia deformação a frio apresentou glóbulos de diâmetros reduzidos, provenientes do mecanismo de globularização envolvido que passa pela recristalização do material, e consequente melhora das propriedades mecânicas em relação ao material sem deformação. O produto tixoconformado apresenta propriedades mecânicas que atendem às especificações do material estudado, embora apresentem, para algumas das condições de fabricação empregadas no trabalho, valores de limite de resistência e de dureza inferiores aos do material fundido sob pressão
Abstract: The goal of this work was the comparative study between the Al-Si5-Cu3-Mg alloy obtained by die casting and thixoforging, based on a commercial accessories bracket used in diesel engines. The die casting commercial part was characterized in terms of structure and mechanical properties, and the final sample obtained by thixoforging was characterized in the same terms, in order to have a comparative base. For thixoability analysis, in other words, the capacity to obtain thixotropic slurries of the alloy under study, it was evaluated by thermal analysis through DSC techniques and thermodynamic simulations using THERMOCALC® software. Transformations temperatures and ranges are discussed, proposing thixoforging windows. The alloy was submitted for globularization thermal treatments under 120 and 300s, and solid fractions 45 and 60%, beyond the influence evaluation of a preliminary cold forming before the thixoforging process. The alloy proved to be interesting to produces thixotropic slurries, with solidification range around 100°C, besides a favorable liquid fraction vs temperature to define the thixoforging window. This thixotropic behavior allowed the complete matrix filling and thixoforged samples were obtained with a good quality, highlighting the porosity decreasing in comparison with the die casting component (around 17 times less). Reduced globules sizes were obtained with previous cold forming, due to the involved globularization mechanism of the recrystallization, and consequent mechanical properties improving in face of non cold forming material. Thixoforged product presents mechanical properties according to the studied alloy specifications, although for some manufacturing conditions present lower tensile strength and hardness when compared with die casted component
Mestrado
Materiais
Mestre em Engenharia Automobilistica
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Piolatto, Alex. "Structural response including vertical component of ground motion /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1966541941&sid=4&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Compton, Mark A. "Components and assembly factors of the yeast vacuolar-type H⁺-translocating ATPase /." view abstract or download file of text, 2006. http://proquest.umi.com/pqdweb?did=1188872021&sid=3&Fmt=2&clientId=11238&RQT=309&VName=PQD.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--University of Oregon, 2006.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 93-99). Also available for download via the World Wide Web; free to University of Oregon users.
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Zheng, Xinhua. "Working memory components as predictors of children's mathematical word problem solving processes." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?did=1871874331&sid=1&Fmt=7&clientId=48051&RQT=309&VName=PQD.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--University of California, Riverside, 2009.Includes abstract. Includes bibliographical references (leaves 83-98). Issued in print and online. Available via ProQuest Digital Dissertations.
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Cho, Soohyun. "Component processes of analogical reasoning and their neural substrates." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1619392411&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Ferguson, Charles Edward. "An analysis of training components of intramural basketball official's programs from selected universities /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1240702481&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Filipiak, Stephen Nicholas. "A component analysis of interteaching in an undergraduate rehabilitation course /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1885443191&sid=6&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Aderinlewo, Olufikayo Oluwaseun. "Assessment of a transportation infrastructure system and its component interactions." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 378 p, 2008. http://proquest.umi.com/pqdweb?did=1617913671&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Liu, Yi. "BoxScript : a language for teaching component-oriented programming /." Full text available from ProQuest UM Digital Dissertations, 2005. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1276391241&SrchMode=1&sid=8&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1185305902&clientId=22256.
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McCusker, Emily Clare. "Overcoming expression obstacles in producing functional components of the G-protein coupled receptor pathway." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 328 p, 2008. http://proquest.umi.com/pqdweb?did=1481676251&sid=31&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Matos, Mariana Aguiar de. "Efeitos de uma sess?o de exerc?cio f?sico aer?bico em componentes celulares e moleculares relacionados ? resist?ncia a insulina em indiv?duos obesos." UFVJM, 2012. http://acervo.ufvjm.edu.br/jspui/handle/1/793.
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Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG)
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq)
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes)
A maior quantidade de ?cidos graxos livres e de citocinas pr?-inflamat?rias plasm?tica presentes na obesidade, podem desencadear a resist?ncia a insulina, dentre outros fatores, pela fosforila??o inibit?ria do substrato do receptor de insulina 1 (IRS-1), via ativa??o de quinases relacionadas ao estresse, como a quinase C-jun N-terminal (JNK). Em obesos, a resist?ncia a insulina correlaciona-se com altera??es do sistema imune, e com a baixa express?o da prote?na de choque t?rmico de 72kDa (Hsp72) e aumento da ativa??o da JNK no m?sculo esquel?tico. Considerando que o exerc?cio f?sico aer?bico promove melhora da sensibilidade a insulina e tem um efeito anti-inflamat?rio. O objetivo desse estudo foi avaliar os efeitos de uma sess?o de exerc?cio f?sico aer?bico na express?o da HSP70, ativa??o da JNK e fosforila??o do IRS-1 no res?duo de serina 612 (IRS-1 ser612) no m?sculo esquel?tico de obesos. Al?m disso, foi avaliada a frequ?ncia dos linf?citos T auxiliares (CD4+) e citol?ticos (CD8+) e das subpopula??es de mon?citos cl?ssicos (CD14++CD16-), intermedi?rios (CD14++CD16+) e n?o cl?ssicos (CD14+CD16++). Os participantes do estudo (n=27) foram alocados em tr?s grupos experimentais (eutr?ficos sens?veis a insulina, obesos sens?veis a insulina, obesos resistentes a insulina) de acordo com a classifica??o do estado nutricional, de acordo com o ?ndice de massa corporal e presen?a ou n?o de resist?ncia a insulina, definida pelo modelo de avalia??o da homeostase (HOMA1-IR). Amostras de sangue venoso e do m?sculo vasto lateral foram obtidas antes e ap?s uma sess?o de exerc?cio f?sico aer?bico realizado a 60% do VO2pico,em cicloerg?metro, com dura??o de 60 minutos. Para avaliar a frequ?ncia das diferentes popula??es de mon?citos e linf?citos T circulantes utilizou-se a citometria de fluxo. As an?lises da express?o da HSP70, ativa??o da JNK e fosforila??o do IRS-1 ser612 no m?sculo esquel?tico foram feitas pelo procedimento de western blot. Nossos resultados demonstraram que obesos resistentes a insulina apresentam uma maior frequ?ncia de mon?citos intermedi?rios e maior fosforila??o do IRS-1 ser612 comparado aos eutr?ficos, maior ativa??o da JNK e menor express?o da HSP70 em rela??o aos demais grupos. Ap?s 1 hora do t?rmino da sess?o de exerc?cio aer?bico houve redu??o da frequ?ncia dos mon?citos intermedi?rios (CD14++CD16+) e dos linf?citos auxiliares (TCD4+) circulantes. Adicionalmente, a sess?o de exerc?cio induziu no m?sculo esquel?tico maior express?o da HSP70, redu??o da fosforila??o do IRS-1 ser612 nos grupos de indiv?duos obesos e menor atividade da JNK nos obesos resistentes a insulina. Conclui-se que uma sess?o de exerc?cio aer?bico promove altera??es que caracterizam redu??o da inflama??o e/ou estresse celular, que podem contribuir para a modula??o da sensibilidade a insulina promovida pelo exerc?cio f?sico.
Disserta??o (Mestrado) ? Programa Multic?ntrico de P?s-gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012.
ABSTRACT The great amount of free fatty acids and proinflammatory cytokines present in obese individuals may trigger insulin resistance, through the inhibitory phosphorylation of insulin receptor substrate 1 (IRS-1), via activation of kinases related to stress, such as kinase C-Jun N-terminal (JNK). In obese individuals, insulin resistance correlates with alterations of the immune system and lower expression of the heat shock protein of 72kDa (Hsp72) and increased activation of JNK in skeletal muscle. Considering that aerobic exercise improve insulin sensitivity and has an anti-inflammatory effect, the purpose of this study was to evaluate the effects of a bout of aerobic exercise in the expression of HSP70, activation of JNK and phosphorylation of IRS-1 in serine residue 612 (IRS-1 ser612) in skeletal muscle of obese patients. Furthermore, we assessed the frequency of helper T lymphocytes (CD4 +) and cytolytic (CD8 +) and subpopulations of classical (CD14 + + CD16-), intermediate (CD14 + + CD16 +) and non-classical (CD14 + CD16 + +) monocytes. Study participants (n = 27) were divided into three experimental groups (eutrophic sensitive to insulin, insulin-sensitive obese, insulin-resistant obese) according to the classification of nutritional status, according to the body mass index, and the presence or absence of insulin resistance, defined by the homeostasis assessment model (HOMA1-IR). Venous blood and vastus lateralis samples were obtained before and after a bout of aerobic exercise performed at 60% of VO2peak on a cycle ergometer, lasting 60 minutes. To assess the frequency of the different populations of monocytes and T lymphocytes circulating we used flow cytometry. Analyses of of HSP70 expression, JNK activation and IRS-1 phosphorylation of ser612 in skeletal muscle were performed by western blot. Our results showed that obese insulin resistant subjects have an increased frequency of intermediate monocytes and higher phosphorylation of IRS-1 ser612 compared to normal weight individuals, and greater activation of JNK and lower expression of HSP70 than the other two groups. 1 hour after the exercise bout, we observed reductions on the frequency of intermediate circulating monocytes (CD14 + + CD16 +) and helper cells (CD4 +). Additionally, the exercise bout induced in the skeletal muscle higher expression of HSP70, decreased phosphorylation of IRS-1 ser612 in the obese groups and lower activity of JNK in the obese insulin resistant individuals. It is concluded that a bout of aerobic exercise promotes changes that characterize reduction of inflammation and / or cellular stress, which may contribute to the modulation of insulin sensitivity promoted by exercise.
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Murphy, Erin Brigid. "The synthesis and characterization of single component thermally remendable polymer materials." Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1835447651&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Zhu, Lin. "Physiological and genetic characterization of surface components involved in adherence and pathogenesis in Streptococcus mutans." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1456284171&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Soames, Kieron, and Jonas Lind. "Detecting Cycles in GraphQL Schemas." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156174.
Повний текст джерелаАнотація:
GraphQL is a database handling API created by Facebook, that provides an effective al-ternative to REST-style architectures. GraphQL provides the ability for a client to spec-ify exactly what data it wishes to receive. A problem with GraphQL is that the freedomof creating customized requests allows data to be included several times in the response,growing the response’s size exponentially. The thesis contributes to the field of GraphQLanalysis by studying the prevalence of simple cycles in GraphQL schemas. We have im-plemented a locally-run tool and webtool using Tarjan’s and Johnson’s algorithms, thatparses the schemas, creates a directed graph and enumerates all simple cycles in the graph.A collection of schemas was analysed with the tool to collect empirical data. It was foundthat 39.73 % of the total 2094 schemas contained at least one simple cycle, with the averagenumber of cycles per schema being 4. The runtime was found to be on average 11 mil-liseconds, most of which consisted of the time for parsing the schemas. It was found that44 out of the considered schemas could not be enumerated due to containing a staggeringamount of simple cycles. It can be concluded that it is possible to test schemas for cyclicityand enumerate all simple cycles in a given schema efficiently.
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Mulligan, Thomas H. Lugg Elizabeth T. "The relationship between components of remedial intersession classes in year round schools and student outcomes." Normal, Ill. : Illinois State University, 2005. http://proquest.umi.com/pqdweb?index=0&did=1225103421&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1176474930&clientId=43838.
Повний текст джерелаАнотація:
Thesis (Ph. D.)--Illinois State University, 2005.Title from title page screen, viewed on April 13, 2007. Dissertation Committee: Elizabeth Lugg (chair), Dianne Gardner, Joseph Pacha, John Rugutt. Includes bibliographical references (leaves 151-156) and abstract. Also available in print.
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Starks, Tyrel J. "Psychometric analysis of the Attraction/Intimacy Assessment Inventory : outlining the construct of sexual orientation and assessing its components /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1895040751&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Thesis (Ph. D.)--Southern Illinois University Carbondale, 2009."Department of Psychology." Keywords: Sexual orientation, Sexual behavior, Sexual attraction, Sexual identity, Gay, Lesbian, Bisexual, Bisexual mental health, Assessment, Attraction/Intimacy Assessment Inventory Includes bibliographical references (p.148-157). Also available online.
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Carril, Dennis F. "Effects of repeated prescribed fire and thinning from below on understory components of southern Illinois oak-hickory forests /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1885437621&sid=17&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Stephanou, Nicolas Constantinos. "Mycobacterial non-homologous end-joining : molecular mechanisms and components of a novel DNA double strand break repair pathway /." Access full-text from WCMC, 2008. http://proquest.umi.com/pqdweb?did=1528973431&sid=21&Fmt=2&clientId=8424&RQT=309&VName=PQD.
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Oristian, Daniel S. "Skeletal phenotype of mice lacking HIP/RPL29, a component of the large ribosomal subunit." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 70 p, 2007. http://proquest.umi.com/pqdweb?did=1397900441&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Gallota, Fabiana Dias Costa. "Avaliação dos níveis de concentração e identificação de fontes de hidrocarbonetos na Bacia do Alto Iguaçu: estudo de caso pós derrame acidental de óleo na refinaria Presidente Getúlio Vargas." Niterói, 2016. https://app.uff.br/riuff/handle/1/1669.
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Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências-Geoquímica. Niterói, RJ
Os hidrocarbonetos presentes no ambiente consistem em misturas complexas de compostos derivados de múltiplas fontes. Os combustíveis fósseis representam a principal contribuição, devido à taxa e escala espacial, em que o petróleo tem sido usado como fonte de energia e matéria-prima para a indústria química. O objetivo deste estudo foi avaliar os níveis de concentração e identificar fontes de hidrocarbonetos na Bacia do Alto Iguaçu e, em especial, na área de influência da Refinaria Presidente Getúlio Vargas (REPAR). Além dos fatores de poluição crônica, a área de estudo foi alvo de um derrame acidental de petróleo em julho de 2000. Diversos indicadores em diferentes compartimentos ambientais (água superficial, sedimento, solo e água subterrânea) foram avaliados na fase pós-derrame e no monitoramento ambiental ao longo de várias campanhas por mais de uma década. Os esforços de avaliação foram concentrados nos seguintes indicadores: os nalcanos, os alcanos isoprenoides, os hidrocarbonetos policíclicos aromáticos (HPA), os biomarcadores de petróleo e ainda o total de hidrocarbonetos de petróleo (THP). Os resultados identificaram como principal aporte de matéria orgânica para as águas superficiais dos rios Barigüi e Iguaçu, os fluxos materiais originados em região a montante do acidente, refletindo a contribuição antropogênica crônica da cidade de Curitiba. Em 2007 e 2008, as concentrações de THP e HPA nas águas superficiais e sedimentos dos rios Barigüi e Iguaçu refletem uma expressiva melhoria nas condições desses rios em relação a 2000. Na área interna da refinaria (Ponto Zero), observou-se uma nítida diminuição (atenuação) natural das concentrações de THP no solo em todas as profundidades dos perfis amostrados ao longo do tempo nos Banhados 1 e 4 e, em particular, uma diminuição importante das concentrações entre 2004 e 2007. Para a identificação das fontes de hidrocarbonetos foram utilizadas razões diagnósticas e quimiometria. As razões diagnósticas calculadas a partir de concentrações de HPA sugeriram que, na maioria dos sedimentos dos Rios Barigüi e Iguaçu coletados nas campanhas de 2000 e 2001, a fonte petrogênica é a principal. Somente na estação a montante do acidente no Rio Barigüi, a fonte pirolítica predominou nestas duas campanhas. As razões diagnósticas que apresentaram maior eficiência na identificação de fontes de hidrocarbonetos nos sedimentos dos rios Barigüi e Iguaçu foram: ΣC1-Fenantrenos/Fenantreno; e (ΣHPA parentais de 3-6 anéis)/(Σ5 séries de HPA alquilados). A identificação de fontes através de razões diagnósticas calculadas a partir de áreas e alturas de picos cromatográficos demonstrou sua aplicabilidade verificando a relação entre os compostos encontrados em amostras de solo da área interna da refinaria com a amostra de petróleo derramado no acidente, após quase uma década da ocorrência do vazamento. A identificação de fontes através método de quimiométrico baseado na análise de componentes principais (ACP) de seções pré-processadas e combinadas dos Cromatogramas de Íons Selecionados (CIS) mostrou que as amostras mais contaminadas estão na área interna da refinaria. Essas amostras apresentam um padrão de distribuição petrogênica e diferentes graus de intemperismo. As amostras da área externa à refinaria (Guajuvira, General Lúcio e Balsa Nova) são menos ou não contaminadas e/ou contém uma mistura de contribuições diagenéticas, pirolíticas e petrogênicas onde predominam diferentes proporções. Os locais mais distantes da atividade industrial (Balsa Nova) contem, como esperado, os níveis mais baixos de contaminação por HPA. Os resultados de biomarcadores demonstraram que não há evidências para concluir que as amostras da área externa à refinaria e o óleo Cusiana vazado tenham a mesma origem. Os resultados ao longo dos rios Barigüi e Iguaçu e do Ponto Zero demonstraram que as ações de emergência para a contenção do óleo foram adequadas para os rios, e que a contaminação decorrente do derrame ficou predominantemente contida no Ponto Zero e diminuiu significativamente após uma década.
Hydrocarbons present in the environment consist of complex mixtures of compounds derived from multiple sources. The main contribution lies on fossil fuel inputs due to the rate and spatial scale by which petroleum has been used as an energy source and chemical feedstock. The aim of this study was to assess the concentration levels and identify sources of hydrocarbons in the Upper Iguaçu Watershed and, in particular, in the area of influence of the President Getulio Vargas Refinery (REPAR). In addition to the factors of chronic pollution, the study area was the scenario of an acute accidental oil spill in July 2000. Numerous indicators in different environmental compartments (surface water, sediment, soil and groundwater) were assessed in the post spill phase and during the environmental monitoring programs over the course of several campaigns for more than a decade. Assessment efforts were concentrated on the following indicators: n-alkanes, alkanes isoprenoids, polycyclic aromatic hydrocarbons (PAH), petroleum biomarkers and total petroleum hydrocarbons (TPH). The results identified as the main contribution of organic matter to surface waters of the Barigüi and Iguaçu Rivers the materials flows originated in the region upstream of the accident, reflecting chronic anthropogenic contribution of the city of Curitiba. In 2007 and 2008, the TPH and PAH concentrations in surface waters and sediments of the Barigüi and Iguaçu Rivers revealed a significant improvement in the conditions of these rivers when compared with 2000. Inside the refinery area (Point Zero), it was observed a clear natural decrease (attenuation) of the concentrations of TPH in the soil at all depths sampled over time in Marshes 1 and 4 and, in particular, an important decrease of concentrations between 2004 and 2007. Diagnostic ratios and chemometrics were used to identity hydrocarbon sources. The diagnostic ratios calculated from the concentrations of PAH suggested that, in the majority of sediments from the Barigüi and Iguaçu Rivers collected in 2000 and 2001 campaigns, the main source is petrogenic. Only in the station upstream the accident in the Barigüi River, the pyrolytic source predominated in these two campaigns. The diagnostic ratios that presented higher efficiency in identifying sources of hydrocarbons in sediments of the Barigüi and Iguaçu Rivers were: ΣC1- Phenantrenes/Phenanthrene; and (Σ3-6 rings parental PAH)/(Σ5 alkylated PAH series). The source identification through diagnostic ratios calculated from heights and areas of chromatographic peaks demonstrated its applicability establishing a relationship between the compounds found in soil samples of the internal area of the refinery and the sample of the oil spilled in the accident, after nearly a decade of occurrence of the spillage. The source identification through chemometric method based on principal components analysis (PCA) of preprocessed and combined sections of Selected Ion Chromatograms (SIC) showed that the most contaminated samples are inside the refinery area. These samples present a petrogenic pattern and different weathering degrees. Samples from outside the refinery area (Guajuvira, General Lúcio e Balsa Nova) are either less or not contaminated, and/or contain mixtures of diagenetic, pyrogenic and petrogenic inputs where different proportions predominate. The locations farthest away from industrial activity (Balsa Nova) contain, as expected, the lowest levels of PAH contamination. The biomarkers results do not show any evidences to conclude positive matches between the samples from outside the refinery area and the spilled Cusiana oil. The results along Barigüi and Iguaçu rivers and Point Zero demonstrated that emergency actions to contain the oil were appropriate for the rivers, and that the contamination resulting from the spill was mostly contained in the Point Zero and decreased significantly after one decade
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Bourret, Travis John. "The PhoPQ two-component regulatory system : at the crossroads of nitrosative stress and Salmonella pathogenesis /." Connect to full text via ProQuest. Limited to UCD Anschutz Medical Campus, 2008. http://proquest.umi.com/pqdweb?did=1545957681&sid=1&Fmt=6&clientId=18952&RQT=309&VName=PQD.
Повний текст джерелаАнотація:
Thesis (Ph.D. in Microbiology) -- University of Colorado Denver, 2008.Typescript. Includes bibliographical references (leaves 112-132). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;
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Doordan, Deborah L. "Coaches, a component of the professional development system a plan for the Christina School District /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 184 p, 2007. http://proquest.umi.com/pqdweb?did=1654487601&sid=5&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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