Dissertations / Theses: 'Belt transmission'

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Tawi, K. B. "Investigation of belt misalignment effects on metal pushing v-belt continuously variable transmission." Thesis, Cranfield University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387629.

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McCandless, John Gregory. "Design of a belt-driven continuously variable transmission." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/12147.

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Notini, Luca. "Condition monitoring of belt based motion transmission systems." Thesis, Loughborough University, 2005. https://dspace.lboro.ac.uk/2134/20371.

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A key asset of Royal Mail Group consists of a nationwide network of sorting offices that forms a constituent component of the means through which the organisation provides an efficient nationwide postal service within the United Kingdom. It may be argued that the efficiency currently possessed by modem sorting offices is due to the utilisation of machines that automate the process of sorting items of mail. The modem letter-sorting machine possessed by Royal Mail can sort up to 30,000 letters per hour; such machines serve as an example of an achievement of the application of Mechatronics. The maintenance of letter sorting machines constitutes a large overhead for the organisation. In the face of competition from pervasive electronic media within the personal communications market and the prospect of deregulation, Royal Mail seeks to streamline its operation in part by the reduction of the overheads incurred through maintenance of letter sorting machinery. The adoption of condition based maintenance techniques and predictive maintenance, for letter sorting machine components such as belts and bearings, forms part of the strategy through which Royal Mail seeks to reduce this overhead. Utilisation of flat belts and timing belts for the implementation of key functions in letter sorting machinery, such as the transportation of items of mail within the mail sorting process, results in the use of many such components within letter sorting machinery. A direct link exists between the maintenance of peak performance of a sorting machine and the maintenance of belt drives; as such the maintenance of belt drives forms a substantial component of the maintenance overhead. The focus of this thesis consists of the condition monitoring of belt based motion transmission systems and in particular, flat belts. The research that forms the basis of this thesis consists of three elements. Firstly, consideration of current knowledge of belt based power transmission such as knowledge of the mechanics of the belt based power transmission process within the context of condition monitoring.

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Parker, Ian Kenneth. "Synchronous belt mechanics and life prediction : a fundamental investigation into the mechanics of toothed belts for automotive camshaft drives, and the prediction of belt life in operation." Thesis, University of Bradford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294351.

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Tanzariello, Roberta. "Condition Monitoring of a Belt-Based Transmission System for Comau Racer3 Robots." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14354/.

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This project has been developed in collaboration with Comau Robotics S.p.a and the main goal is the development in China of an Health Monitoring Pro-cess using vibration analysis. This project is connected to the activity of Cost Reduction carried out by the PD Cost Engineering Department in China. The Project is divided in two part: 1. Data Acquisition 2. Data Analysis An Automatic Acquisition of the moni.log file is carried out and is discussed in Chapter 1. As for the Data Analysis is concerned a data driven approach is considered and developed in frequency domain through the FFT transform and in time domain using the Wavelet transform. In Chapter 2 a list of the techiques used nowadays for the Signal Analysis and the Vibration Monitoring is shown in time domain, frequency domain and time-frequency domain. In Chapter 3 the state of art of the Condition Monitoring of all the possible ma-chinery part is carried out from the evaluation of the spectrum of the current and speed. In Chapter 4 are evaluated disturbances that are not related to a fault but be-long to a normal behaviour of the system acting on the measured forces. Motor Torque Ripple and Output Noise Resolution are disturbance dependent on ve-locity and are mentioned in comparison to the one related to the configuration of the Robot. In Chapter 5 a particular study case is assigned: the noise problem due to belt-based power transmission system of the axis three of a Racer 3 Robot in Endu-rance test. The chapter presents the test plan done including all the simula-tions. In Chapter 6 all the results are shown demostrating how the vibration analysis carried out from an external sensor can be confirmed looking at the spectral content of the speed and the current. In the last Chapter the final conclusions and a possible development of this thesis are presented considering both a a Model of Signal and a Model Based approach.

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Micklem, J. D. "The investigation and modelling of the steel compression V-belt continuously variable transmission." Thesis, University of Bath, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359731.

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ter, Beek Marc [Verfasser]. "Active control of coupled vibrations in belt drives for power transmission / Marc ter Beek." Aachen : Shaker, 2016. http://d-nb.info/1138177970/34.

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Beek, Marc ter [Verfasser]. "Active control of coupled vibrations in belt drives for power transmission / Marc ter Beek." Aachen : Shaker, 2016. http://nbn-resolving.de/urn:nbn:de:101:1-201708132190.

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Messick, Matthew James. "An Experimentally-Validated V-Belt Model for Axial Force and Efficiency in a Continuously Variable Transmission." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/85055.

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Rubber V-belt Continuously Variable Transmissions (CVT's) are commonplace in the Baja SAE collegiate design competition, and are also used widely in the power sports industry. These transmissions offer benefits of simplicity in mechanical design, consisting of only two pulleys, and are easy to use. While most teams in the competition use commercially available designs, custom designs are becoming more common, and the Baja team at Virginia Tech has used custom CVT's since the 2014 season. The design of these CVT's has relied heavily on trial and error, requiring significant adjustments to be made during the testing phase. In addition, only qualitative information is known for the relationship between efficiency and design parameters, such as sheave angle. The goal of this thesis is to create an improved V-belt model that may be used as a design tool. This model provides quantitative information about efficiency that can be used to make more informed design decisions. The belt model also provides insight into the magnitude and relationship between the axial forces in the pulleys. This can be used to create an initial design that is more accurate, and possibly reduce the time required for tuning. A CVT dynamometer was constructed to validate the analytical results for efficiency, and this will also serve as a tuning tool for future Baja teams at Virginia Tech. This thesis will advance the state of the custom CVT design and testing process at Virginia Tech, and hopefully lead to improved results at competition in the future. Master of Science

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Akehurst, Sam. "An investigation into the loss mechanisms associated with a pushing metal V-belt continuously variable transmission." Thesis, University of Bath, 2001. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341585.

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Silva, Carlos Alexandre Ferreira Da. "Modeling and optimization of power losses in poly-V belt transmissions : Application to the Front Engine Accessory Drive of trucks." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI079/document.

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Ces travaux s’inscrivent dans le cadre du projet EDIT(Efficient Distribution Truck, FUI19), piloté par le groupe Volvo Trucks, dont l’objectif de réduction de consommation pour 2020 est fixé à 13% par rapport à un véhicule actuel EURO-6. Le projet EDIT porte sur cinq axes techniques d’amélioration dont un consiste en l’obtention d’un système optimisé de transmission par courroie poly-V au regard des pertes de puissance. Actuellement les faces avant de moteur sont perfectionnées sur le plan mécanique ; cela signifie que la durée de vie de ses composants est optimisée, et que les nuisances vibratoires sont réduites. Par contre, des améliorations peuvent être apportées sur le plan énergétique. Cette thèse, qui a pour objectif d’investiguer les possibilités de réduction et d’optimisation des pertes de puissance sur les façades accessoires, se décline en trois parties : une caractérisation par l’analyse mécanique dynamique des matériaux viscoélastiques des courroies poly-V et des composantes de façade ; une modélisation, une optimisation et une implémentation logicielle des modèles de pertes de puissance ; validées par une dernière partie expérimentale sur banc d’essais. Les pertes de puissances dans une face avant moteur sont de plusieurs types : des pertes internes à la courroie poly-V (hystérésis du caoutchouc), des pertes externes à la courroie (glissement poulie/courroie) et des pertes internes aux composants (frottement dans les roulements). Ces pertes peuvent désormais être quantifiées et optimisées grâce aux modèles développés durant cette thèse. Ces modèles ont été validés et implémentés dans un outil de simulation (PLFead, Power Loss Front engine accessory drive), qui a été développé pour optimiser les pertes de puissance en tenant compte des paramètres de design et de fonctionnement des faces avant moteur This work is a part of the Efficient Distribution Truck (EDIT, FUI 19) project, led by Volvo Trucks, whose objective is to reduce distribution vehicles’ fuel consumption for 2020 by 13% when compared with the current production vehicle EURO-6. The EDIT project targets five areas of research and technical solutions, one of which consists of obtaining an optimized poly-V belt transmission concerning the power losses. In terms of lifetime of the mechanical components, reduction of noise and vibrations, the Front Engine Accessory Drives (FEADs) are currently one of the most technologically sophisticated systems. However, further improvements can be made to make the vehicles more energy efficient. This thesis, which aims at investigating possibilities for reducing and optimizing the power losses in the FEADs, is composed of three main parts: the characterization of the viscoelastic materials of the poly-V belts via Dynamic Mechanical Analysis (DMA) and the FEAD components; the modeling, the optimization and the implementation of the power loss models in a simulation tool; and their experimental validation through a test bench. The power losses occurring in a FEAD are of several types: poly-V internal losses (hysteresis of the belt-rubber), poly-V external losses (belt/pulley slip) and losses from the accessory drives (friction inside the bearings). These power losses can be quantified and optimized thanks to the models developed throughout this thesis. These models have been validated and implemented in a simulation tool (PLFead, Power Loss Front engine accessory drive), which has been developed to optimize the power losses taking into consideration the design parameters and operating conditions of the FEAD

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Narita, Keiichi. "Influences of metal-metal friction characteristics on the performance of metal V-belt type continuously variable transmission." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445840.

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Passos, Sébastien. "Dynamique des systèmes d'entraînement par courroie synchrone intégrant des poulies à profils innovants." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI049.

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Dans le domaine automobile, l’utilisation de poulies ayant un profil primitif non circulaire (NC) est devenue chose courante pour la conception des façades de distribution par courroie synchrone des moteurs à combustion interne. Pour des paramètres de conception bien choisis (forme, calage angulaire), ces poulies innovantes permettent à priori de réduire l’impact vibratoire des sources d’excitation angulaire affectant la façade. La phénoménologie associée aux poulies NC s’avère toutefois complexe et difficile à prédire par le calcul. Le dimensionnement des façades équipées de ces dispositifs s’avère délicat mais primordial. Dans ce contexte, un modèle numérique adapté à la simulation de la dynamique angulaire des façades de distribution intégrant des poulies NC a été proposé. Ce modèle est fondé sur une approche discrète (0D/1D) inspirée de modèles classiquement utilisés pour l’étude des transmissions intégrant uniquement des poulies circulaires. La courroie est associée à un solide élastique 1D uniforme en prise sur l’enveloppe de solides 2D indéformables représentant les poulies. L’interaction poulie-courroie est concentrée aux points de tangence localisés aux frontières des brins de courroies. En ces points, s'exercent les efforts de tension résultant de l’élongation des brins. Le mouvement des points tangence, engendré par les poulies NC, est pris en compte par l’emploi d’une formulation originale pour le calcul de l'élongation des brins. Cette formulation est obtenue par l’application d’un bilan de matière opéré sur la courroie via une méthode Lagrangienne-Eulérienne. En parallèle de la Modélisation, des travaux expérimentaux ont permis d’analyser l’impact d’une poulie bilobée sur la dynamique angulaire d’une façade de distribution (moteur à 4 cylindres). Le dispositif expérimental utilisé a été spécialement développé dans le cadre de cette thèse. Son instrumentation permet une analyse complète du comportement en dynamique angulaire de la façade. Des comparaisons calculs/essais ont finalement permis de valider le modèle numérique proposé In response to ever-stricter requirements for internal combustion engine efficiency, noise and reliability, car manufacturers now commonly design Timing belt drives comprising innovative pulleys with non-circular (NC) profiles. For well-chosen design parameters (profile shape, angular phasing), the use of a NC pulley can considerably improve the vibratory performances of a timing belt transmission. Nevertheless, designing efficiently a belt transmission including NC pulleys remains hard to accomplish. To achieve this, it is important to clearly understand and identify the impact of such pulleys on the dynamic behaviour of Timing belt drives. In this context, a numerical model able to simulate the angular dynamics of Timing belt drives comprising NC pulleys has been developed. The model is based on a discrete approach (0D/1D), similar to the models of transmissions with circular pulleys only. The belt is modelled as a 1D linear elastic material (wire) and the pulley are considered as rigid bodies represented by rotary inertias. Rotations of the driven pulleys are the degrees of freedom of the discrete system. The pulley rotation is actuated by the effect of the belt span tensions applied at the belt/pulley seating/unseating points. In the case of a NC pulley, these points are mobile and their motion has to be tracked rigorously. To achieve this, a novel formulation has been written by establishing a feed-in/out balance on the belt spans using a Lagrangian-Eulerian method. In parallel to the numerical developments, experimentations have been performed for analysing the impact of an oval pulley on Timing belt drive angular dynamics (4 cylinder engine). The experimental test rig has been fully developed during this thesis. It is equipped with numerous sensors that enable a complete analysis of belt transmission angular dynamics. Finally, comparative analyses have shown a quite good agreement between experiments and simulations

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Zhu, Farong. "Nonlinear dynamics of one-way clutches and dry friction tensioners in belt-pulley systems." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1158689667.

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Gonçalves, Luiz José Martins. "Influência do comportamento dinâmico de uma correia de multicanais em um sistema de acessórios automotivo utilizando tensionador automático." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263852.

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Orientador: Douglas Eduardo Zampieri Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica Made available in DSpace on 2018-08-16T17:33:09Z (GMT). No. of bitstreams: 1 Goncalves_LuizJoseMartins_M.pdf: 54959768 bytes, checksum: acc14baad96c73d181af0a7cda323087 (MD5) Previous issue date: 2010 Resumo: Neste trabalho procurou-se avaliar comparativamente a simulação numérica e os testes em dinamômetro quanto à frequência de ressonância do trecho livre da correia multicanais do lado tenso de um sistema de três polias contendo um tensionador automático. Para isto é necessário conhecer as características do tensionador, disposição e inércia dos acessórios e as características da correia. Para a análise descrita neste trabalho utilizou-se um método de determinação das frequências de ressonâncias através de um sistema massa-mola através de simulação computacional, e avaliação em testes práticos com medições dos níveis de aceleração no tensionador de correia, e deslocamento máximo da correia em seu trecho livre. Os resultados obtidos foram analisados e comparados com o resultado teórico. Os resultados deste trabalho são importantes nos futuros trabalhos de um sistema não-linear com multi-polias visando à otimização do sistema Abstract: This investigation looked for to developing a method that allowed evaluating the simplified numerical simulation and the tests in dynamometer to identify resonance frequencies of poly V belt span. For that is necessary to know the characteristics of the belt tensioner, coordinates and inertia of the accessories and the characteristics of the poly V belt. For the described analysis in this work a method of determination of the frequencies of resonances through a system was used mass-spring, and evaluation in practical tests with measurements of the levels of acceleration in the tensioner arm, and maximum displacement and acceleration of belt span. The final results was checked and compared with numerical simulation. The results of this work are important in the future works of a nonlinear system with multi-pulleys aiming at the system optimization Mestrado Dinâmica Mestre em Engenharia Automobilistica

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Rotimbo, Mbourou Donald Romarick. "Contribution à la surveillance et au diagnostic de défauts dans les systèmes de transmission par courroie." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSES052.

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Dans cette thèse, nous nous proposons d’investiguer les signaux expérimentaux provenant des transmissions par courroie, afin d’envisager par exemple le diagnostic de la tension. N’étant pas issu du domaine de la Mécanique, nous présentons donc une bibliographie exhaustive et thématique sur la théorie et l’expérimentation dans les systèmes transmissions par courroie. Le résumé de ce travail a permis de choisir une approche de modélisation mécanique correspondant au mieux aux conditions réelles de fonctionnement de notre système. Elle inclut les variations temporelles dans la vitesse de rotation du moteur qui entraîne la transmission entière et des changements dans la tension de la courroie. Malheureusement, nous n’avons pas réussi à implémenter numériquement les équations de simulation. Néanmoins, les conclusions que nous en tirons nous aident par la suite à mieux comprendre et interpréter les résultats expérimentaux obtenus, après application de l’ensemble des procédures de Traitement du signal. Notre panoplie d’outils de traitements numériques est tirée d’une longue analyse comparative des différents algorithmes de Traitement du Signal existants, dédiés à la surveillance, au diagnostic et au pronostic des défaillances observées sur les roulements et les engrenages. Nous les avons réadaptés pour convenir à l'étude des paramètres variables (tension, charge et/ou vitesse) qui peuvent apparaître dans les transmissions par courroie. Le principal intérêt de notre travail est le développement d’une procédure automatisée et efficace, permettant un suivi fiable des défaillances, dans les domaines d’analyses : modale, traditionnelle (temporelle, fréquentielle, spectrale), synchrone, temps-fréquence et surtout « cyclostationnaire » . Dans ce dernier domaine, avec des méthodes d’extraction de sources à partir d’un signal préalablement rééchantillonné, nous étudions spécifiquement les composantes périodique et aléatoire. Chaque type de défaut (variations au niveau de la tension, la charge et/ou la vitesse) a une signature que nous cherchons à distinguer avec des indicateurs de condition(temporels, fréquentiels et spectraux). Nous essayons de comparer les résultats expérimentaux à la théorie sur les transmissions par courroie. Grâce aux méthodes et algorithmes développés dans ce travail de thèse, nous apportons une contribution permettant de traiter un certain nombre de problèmes inhérents aux transmissions par courroies, à partir de leurs signaux expérimentaux acquis sur des accéléromètres, des jauges de contraintes et des codeurs optiques In this PHD, we investigate experimental signals recorded from belt drives with a diagnosis aim of belt tension. Our research works present an exhaustive and thematic bibliography on theory and experimentation in belt drive to complete our insufficient knowledges in mechanical domain. We choosed a theoritical approach nearest real conditions of our belt drives bench. We included time fluctuaction in drive shaft speed and blet changes. Unfortunately, we could not resolve motion equations because existence of numerical limits. All conclusions will be used to understand and interprate experimental results after our signal processing numerical procedures. Our tools panel of numerical process comes from a comparative analysis extracted in several scientific documents and differents algorithms. They dedicate to surveillance, diagnosis and pronostic oriented toward bear and gear defaults. A adaptation in our belt case is necessary with variables parameters (tension, load and/or speed) affecting our case. In our automatic approach, we study several faults in analysis domains : modal, traditionnal (time, frequency, spectrum), synchronous, time-frequency and « cyclostationary » . In this last domain, we extract both comopnent (discret and random), after an previous resmapling operation applying to raw collected signal. Each falut type has a specific signature to discriminate with pertinent condition indications (time, frequency and spectrum domains). All results are discussed at the end of this PHD document. Our developped methods and algorithms are a contribution to process belt drives problems, from exprerimental signals recording with acceleromertes, constraint gauges and optical coders

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Hübler, Jörg. "Textilverstärkte Zugmittel für die Antriebs- und Fördertechnik mit formschlüssiger Krafteinleitung." Doctoral thesis, Universitätsbibliothek Chemnitz, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-116986.

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Die Arbeit befasst sich mit einem neuen textilverstärkten Zugmittel mit formschlüssiger Krafteinleitung. Im Grundlagenteil werden Aufbau, Eigenschaften und Dimensionierungsgrundlagen von Rollenketten und Zahnriemenantrieben erörtert, sowie textile und elastomere Werkstoffe betrachtet. Aus den Betrachtungen zum Stand der Technik, der Maschenware mit hochfesten Filamentgarnen und deren polymeren Beschichtungen wird der Entwicklungsansatz abgeleitet. Mit Hilfe eines Spezialkettenwirkverfahrens werden die textilen Zugträger als Recht/Links-Maschenware hergestellt. Das besondere daran ist die teilungsgenaue Einbindung der Bolzen in die Maschenstruktur bei der Fertigung. Eine anschließende elastomere Beschichtung verbessert die mechanischen Eigenschaften erheblich und fixiert die Bolzen axial. Dabei werden reaktive Polyurethane im Gießverfahren und thermoplastische Elastomere im Spritzgießverfahren eingesetzt. Drei ausgewählte textile Bindungen mit verschiedenen Beschichtungen wurden statisch und dynamisch, anhand von Proben und endlos verbundenen Zugmitteln, ausführlich untersucht. Die daraus abgeleiteten Bauteil-Wöhlerlinien und Leistungsdiagramme bilden die Grundlage zur Auslegung der textilverstärkten Zugmittel für Anwendungen im Maschinenbau The dissertation deals with a new textile reinforced with form-closed force application. The basis of structure, properties and sizing basics of roller chain drives and belt drives are discussed and considered textile and elastomeric materials. From consideration of the prior art, the knitted fabric with high tenacity filament of polymeric coatings and their development approach is derived. Using a special knitting process, the textile chain tension members are produced as a right / left-knit fabric. The special thing about it is the exact distribution of involvement of the pins in the mesh structure during manufacturing. Subsequent elastomeric coating significantly improves the mechanical properties and fixes the bolt axially. These reactive polyurethanes by casting and thermoplastic elastomers are used in injection molding. Three selected textile bonds with different coatings were statically and dynamically examine in detail the basis of samples and associated endless traction means. The derived component S/N curves and performance charts are the basis for the design of textile-reinforced tension means for applications in mechanical engineering

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Pilemalm, Robert. "TiAlN-based Coatings at High Pressures and Temperatures." Licentiate thesis, Linköpings universitet, Nanostrukturerade material, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112213.

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TiAlN and TiAlN-based coatings that are used of relevance as protection of cutting tool inserts used in metal machining have been studied. All coatings were deposited by reactive cathodic arc evaporation using industrial scale deposition systems. The metal content of the coatings was varied by using different combinations of compound cathodes. The as-deposited coatings were temperature annealed at ambient pressure and in some cases also at high pressure. The resulting microstructure was first evaluated through a combination of x-ray diffraction and transmission electron microscopy. In addition, mechanical properties such as hardness by nanoindentation were also reported. TiAlN coatings with two different compositions were deposited on polycrystalline boron nitride substrates and then high pressure high temperature treated in a BELT press at constant 5.35 GPa and at 1050 and 1300 °C for different times. For high pressure high temperature treated TiAlN it has been shown that the decomposition is slower at higher pressure compared to ambeint pressure and that no chemical interaction takes place between TiAlN and polycrystalline cubic boron nitride during the experiments. It is concluded that this film has the potential to protect a polycrystalline cubic boron nitride substrate during metal machining due to a high chemical integrity. TiZrAlN coatings with different predicted driving forces for spinodal decomposition were furthermore annealed at different temperatures. For this material system it has been shown that for Zr-poor compositions the tendency for phase separation between ZrN and AlN is strong at elevated temperatures and that after spinodal decomposition stable TiZrN is formed.

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Gomes, Leandro Costa Ferreira 1986. "Estudo da conexão da usina de Belo Monte ao SIN através da alternativa de transmissão em meia onda." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259505.

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Orientador: Luiz Carlos Pereira da Silva Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação Made available in DSpace on 2018-08-24T07:39:20Z (GMT). No. of bitstreams: 1 Gomes_LeandroCostaFerreira_M.pdf: 6148500 bytes, checksum: bf5007e253bf40d848b0494ce01ead56 (MD5) Previous issue date: 2014 Resumo: O presente trabalho está inserido num contexto de busca de novas fontes de energia elétrica e de aproveitamento de grandes potenciais energéticos localizados distantes dos principais centros de carga. Para estes, alternativas não convencionais de transmissão também são exigidas, nas quais se insere a transmissão em linhas de pouco mais de meio comprimento de onda, distância de pouco mais de 2500km no sistema brasileiro à 60Hz. Como este tipo de transmissão nunca foi implementado, trata-se de uma proposta inovadora, pouco explorada e que exige ensaios elementares para testar-se a viabilidade, vantagens e desvantagens frente a outras alternativas de transmissão de energia elétrica. Esta dissertação visa investigar alguns aspectos referentes à tal método de transmissão de grandes montantes de potência em distintos cenários de interligação entre as regiões Norte e Sudeste do Brasil do SIN (sistema interligado nacional). Três distintos corredores compostos por linhas de pouco mais de meio comprimento de onda foram ensaiados. Inseridos conectando a usina de Belo Monte no Pará a Assis-SP na rede de 500kV, percorrendo 2664 km. Cada um dos corredores é composto por: três linhas de 800 kV e 4846 MW de potência característica (SIL); um segundo com duas das mesmas linhas de 800kV e um terceiro com duas linhas de 1000 kV e 8100 MW de potência característica. Cada aspecto é ensaiado em seis diferentes situações de carregamento do SIN e de fluxo de potência pelo corredor, abrangendo cenários de alto, médio e baixo carregamento das linhas assim como mudanças no sentido do fluxo entre Norte e Sudeste. Dentre os aspectos abordados estão: a avaliação e redução das perdas manipulando a potência característica operacional das linhas; o controle do carregamento do corredor através do uso de transformadores defasadores não convencionais; a inserção de cargas e geração em pontos intermediários deste e o controle do fluxo de potência reativa. Por fim, o estudo não aborda aspectos transitórios e é realizado com o auxílio do ANAREDE, software elaborado pelo CEPEL Abstract: This work is placed in a search for new sources of power and exploitation of large energy potential located far from major load centers. For the second scenarios, alternate non-conventional transmission are also required, in which half wavelength transmission lines are inserted, resulting in a distance of just over 2500km for the 60Hz brazilian electrical system. Since this type of transmission has never been implemented, it is an innovative solution and few explored, requiring elementary studies to test the feasibility, advantages and disadvantages compared to other alternatives for bulk electric power transmission. This thesis aims to investigate some aspects related to such transmission method for large amounts of power into distinct scenarios of interconnection between the North and Southeast of Brazil's SIN (Brazilian National grid). Corridors consisting of three distinct lines of just over half wavelength were tested. Inserted connecting Belo Monte hydro power plant in Para to Assis in São Paulo through the 500kV network, covering 2664 km, each corridor is composed: by three lines of 800 kV and 4846 MW of Surge Load Impedance (SIL), the second one by two of the same 800kV lines and a third by two lines of 1000 kV and 8100 MW SIL. Each aspect is tested in six different SIN load situations and power flowing through the corridor, covering scenarios of high, medium and low lines loading as well as changes in flow direction between North and Southeast. Among the issues tackled are: evaluation and reduction of losses by manipulating operating lines SIL; line load controlling using non-conventional phase shift transformers; inserting loads and generation at intermediate points of the lines and control of reactive power flow. Finally, the study does not handle with transient aspects and is accomplished with the aid of ANAREDE, software developed by CEPEL Mestrado Energia Eletrica Mestre em Engenharia Elétrica

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恭平, 坂上, та Kyohei Sakagami. "金属Vベルト式CVTの摩擦伝動限界の予測に関する研究". Thesis, https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13071664/?lang=0, 2018. https://doors.doshisha.ac.jp/opac/opac_link/bibid/BB13071664/?lang=0.

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駆動プーリ上の回転変動が金属Vベルトを介して従動プーリへと伝達される際には，摩擦力が飽和状態に近づくにつれ，従動プーリへ伝達される回転変動は減衰する．この回転変動の変化に着目して滑り状態を指標化した． When fluctuations in the speed of rotation of the drive pulley are transmitted to the driven pulley via the metal V-belt, the transmitted fluctuations become attenuated as friction force approaches a state of saturation. The research discussed in this paper focused on these fluctuations in the speed of rotation and developed an index for the slip state between the belt and the pulleys. 博士(工学) Doctor of Philosophy in Engineering 同志社大学 Doshisha University

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Knox, John Graeme. "The engineering development of power transmission belts based on thermoplastic polyurethane elastomers." Thesis, University of Ulster, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270457.

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Garcia, Ubirajara. "Estudo de vibrações em auto-tensionador de transmissão por correias." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265211.

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Orientador: Robson Pederiva Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica Made available in DSpace on 2018-08-14T00:38:10Z (GMT). No. of bitstreams: 1 Garcia_Ubirajara_M.pdf: 2857015 bytes, checksum: 43af4c00365bf303c80b6b5d1be9e9be (MD5) Previous issue date: 2009 Resumo: Neste trabalho desenvolve-se um método, que permite avaliações de parâmetros, para o estudo do projeto de um sistema auto-tensionador no controle de suas vibrações transversais e forças atuantes. Parâmetros construtivos e operacionais, como: a geometria, inércia, rigidez da mola do auto-tensionador, rigidez da correia e condições de operação, como: frequências de excitação, forças estáticas e dinâmicas são obtidas em um sistema auto-tensionador de transmissão por correias, aplicados em automóveis de passeio comerciais. Com a modelagem dinâmica de um grau de liberdade, calcula-se a força de atrito e fator de amortecimento, que estabelece o controle de vibrações e forças atuantes no sistema. Os resultados das simulações computacionais são analisados e comparados com os resultados obtidos pelo protótipo experimental desenvolvido. Os resultados tecno-experimentais indicam ajuste satisfatório, o que representa uma contribuição significativa, para o estudo de sistemas auto-tensionadores e na melhoria do controle de vibrações e forças atuantes em correias dentadas, em tempo real de projeto. Abstract: This investigation describes a method, which permits evaluating the best parameters, in the study of tensioner project system in its transversal vibration control and actuating forces. The construtive and operating parameters, as: geometry, inertia, tensioner spring stiffness, belt stiffness, and operating conditions as: excitation frequencies, estatic and dinamic forces are obtained in a tensioner of transmition by belts with market vehicles aplication. With a dinamical modelling of one degree of fredow are calculated the atrict force and damping factor that establish the vibration control and system actuating forces. The computational simulating results are analysed and compared with obtained results from the developed experimental prototype. The tecno-experimental results have a satisfactory adjust, that represents a significative contribution, for tensioners systems study and the better control of vibrations and actuating forces on driven belts, in project real time. Mestrado Mecanica dos Sólidos e Projeto Mecanico Mestre em Engenharia Mecânica

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Martins, Diego Rodrigo 1987. "Análise dinâmica não linear de sistema de transmissão por correia." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265212.

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Orientador: Robson Pederiva Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica Made available in DSpace on 2018-08-23T14:08:15Z (GMT). No. of bitstreams: 1 Martins_DiegoRodrigo_M.pdf: 7219918 bytes, checksum: 31c54119f27719f2488e9ea8f2a0126e (MD5) Previous issue date: 2013 Resumo: O presente trabalho tem por objeto o estudo de sistemas de transmissão por correia serpentina com tensionador automático, que é uma aplicação automotiva utilizada em larga escala e cujo comportamento dinâmico apresenta grande influência sobre o funcionamento dos acessórios acionados pelo motor. O movimento do eixo de manivelas acionado pelo processo de combustão apresenta como característica a ocorrência de variações de velocidade e torque entregues aos acessórios pelo sistema de transmissão, contudo as flutuações de torque resultantes deste movimento são o principal mecanismo excitador do sistema de transmissão por correia. Níveis elevados de flutuação de torque podem aumentar o nível de tração dinâmica atuante na correia, fazendo com que esta venha a falhar devido à fadiga, ou produzir níveis de vibração torcional elevados nas polias dos acessórios, causando impacto direto em seus suportes. Através de modelos matemáticos é avaliado o comportamento do sistema de transmissão, considerando alguns fenômenos responsáveis por introduzir não linearidades neste. São avaliados, assim, os efeitos de tração inicial, frequências naturais, formas modais e respostas temporais do sistema. Paralelamente é estudado o comportamento de um sistema de transmissão real através da uma investigação experimental. São identificados seus parâmetros lineares através de técnicas de Análise Modal, bem como efeitos de variação destes parâmetros em função da velocidade de operação do sistema. É avaliada a composição em frequência da resposta do sistema quando em operação e também são realizados testes para detecção de não linearidades no sistema Abstract: The objective of the present work is the study of a tensioner loaded belt drive system, which is a recurrent automotive application used in large scale and whose dynamic behavior has great influence on the functioning of various components powered by engine. Crankshaft motion, powered by internal combustion process, presents as characteristic the occurrence of variations on speed and torque delivered to accessory by belt drive, torque fluctuation due to this motion is the main excitation mechanism to belt drive systems though. High levels of torque fluctuation can increase belt dynamic tension making it amenable to fault due to fatigue or produce high levels of torsional vibration on accessory pulleys which has direct impact on its support structure. By means of mathematical models, systems behavior is evaluated, taking into account phenomena responsible for introducing nonlinearities. Initial tractive tension, natural frequencies, modeshapes and time responses of the system are evaluated. In parallel, it is studied the behavior of a real belt drive system through experimental investigation. Linear parameters are identified by Experimental Modal Analysis techniques, and its variation as function of system operating speed, as well. Frequency composition of system's response are evaluated and also are performed tests to detect nonlinearities Mestrado Mecanica dos Sólidos e Projeto Mecanico Mestre em Engenharia Mecânica

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Vgenopoulos, Dimitrios. "An investigation of oriented polymers for power transmission applications." Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/6360.

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The feasibility of using oriented polymer technology in the design and manufacture of mechanical power transmission belts has been investigated. Working from an initial selection of polymers a die-drawing technique for orienting the polymers was devised, and the static and dynamic mechanical properties of the oriented polymers were investigated. These results indicated that PP, PBT, PPS and PEEK were suitable for further research. Of these 4 materials PBT was selected as the most appropriate material for belt manufacture based on cost, processability (drawing temperature, natural draw ratio) and limitations of laboratory equipment. A technique based on free-tensile drawing combined with simultaneous rotational motion was designed and used to manufacture oriented PBT flat belts from cylindrical injection moulded preforms. The technique used a tensile machine with two pulley-clamps, a fitted heated chamber and an electric motor to provide rotational motion to the belt during drawing. Two types of oriented PBT flat belts with different cross sections were produced successfully, termed 'thick' and 'thin'. These belts were tested on a purpose-built rig comprising two equal diameter pulleys, one driven by an electric motor and the other connected to a generator to provide load. The belt life and power transmission performance was investigated at various conditions of speed, transmitted torque and tension, and the results indicated that despite their smaller cross section 'thin' flat belts demonstrated up to 3 times longer life. However life was only 100hours, which was very low compared with conventional flat belts that last for many thousands of hours at higher speeds and much greater power transmission capacity. Synchronous belts were then produced through the same manufacturing method used for flat belts. This aspect of the research concentrated on the initial pitch design and size, i.e. the timing. Initially a rectangular tooth profile was selected for its simplicity in terms of manufacture. The produced belts exhibited high pitch length variation as well as deformed teeth and were not usable for synchronous power transmission. An extra timing feature was included to control orientation; reducing the pitch length variation enabling consistent tooth production. It was observed that the areas between the extra timing feature and the tooth edges did not orient completely with some regions remaining undrawn. Finite Element Analysis (FEA) was used to predict the drawing behaviour of different shapes and dimensions of the timing features. The results suggested that a 4mm wide and 7mm long slot provided the highest possible extension and the minimum non-oriented regions on the groove. Whilst, the thickness and width of the drawn belt timing features showed differences to the FEA predictions, manufactured synchronous belts based on that design had much better controlled dimensions and the lowest achieved pitch length variation ( ±1%), compared to initial attempts. It is concluded that oriented polymers have the potential to be used in power transmission belts since they offer higher stiffness, tensile strength and creep resistance compared with isotropic polymers that are currently used in commercially available belts such as thermoplastic polyurethane (TPU) and polyvinyl chloride (PVC). The main disadvantages were the lack of dimensional stability and number of cycle to failure.

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Lee, Riley. "Yearning for the bell a study of transmission in the shakuhachi honkyoku tradition /." Connect to full text, 1992. http://hdl.handle.net/2123/1742.

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Thesis (Ph. D.)--University of Sydney, 1994. Title from title screen (viewed Oct. 8, 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Music, Faculty of Arts. Degree awarded 1994; thesis submitted 1992. Vol. 2 chiefly consists of musical examples. Includes tables. The thesis consists of 2 vol. Includes bibliographical references. Also available in print form.

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Miller, Alan Henry David. "Best effort measurement based congestion control." Thesis, Connect to e-thesis, 2001. http://theses.gla.ac.uk/1015/.

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Thesis (Ph.D.) -- University of Glasgow, 2001. Includes bibliographical references (p.i-xv). Print version also available. Mode of access : World Wide Web. System requirments : Adobe Acrobat reader reuired to view PDF document.

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Bélanger, Pierre. "Contrôle actif du bruit et des vibrations de la transmission principale d'un Bell 407." Mémoire, Université de Sherbrooke, 2006. http://savoirs.usherbrooke.ca/handle/11143/1446.

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The main objective of this research project is to study the feasibility and effectiveness of active structural acoustic control of the main transmission of a Bell 407 under laboratory conditions. Ultimately this project should lead to a reduction of the level of noise inside the passenger area of this helicopter. This project is a collaborative program between Bell Helicopter Textron Canada Limited, the Consortium for Research and Innovation in Aerospace in Quebec (CRIAQ) and the Groupe d'Acoustique de l'Université de Sherbrooke (GAUS). The first step was the characterization of the source of noise and vibration with vibroacoustic spectra from ground and flight tests on a Bell 407. The tones associated to the transmission in the 500 Hz to 3000 Hz range were identified. Secondly, a laboratory setup was developed. Essentially, this laboratory setup is a simplified representation of the main transmission-roof-cabin system of the Bell 407. The laboratory setup was validated with various impact tests on a Bell 407. Then, a finite element model of the laboratory setup was developed under MSC.NASTRAN. This model was also experimentally validated. The finite element model of the laboratory setup was used to realize many optimal active control simulations. The objective of these simulations was to find a configuration of control actuators and error sensors effective to attenuate the mean square velocity of the receiving panel of the laboratory setup. Finally, the laboratory setup was used for the laboratory demonstration of active control. The most effective configuration obtained from the simulations was experimentally implemented. Promising active control results were obtained with 2 different algorithms, the filtered-reference least mean square (FXLMS) and the principal component least mean square (PCLMS).

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Legout, Arnaud. "Contrôle de congestion multipoint pour les réseaux best effort." Nice, 2000. http://www.theses.fr/2000NICE5451.

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Une des clefs de l'amélioration de la qualité de service pour les réseaux best effort est le contrôle de congestion. Dans cette thèse, on a étudié le problème du contrôle de congestion pour la transmission multipoint dans les réseaux best effort. Cette thèse présente quatre contributions majeures. On a commencé par étudier deux protocoles de contrôle de congestion multipoints RLM et RLC. On a identifié des comportements pathologiques pour chaque protocole. Ceux-ci sont extrêmement difficiles à corriger dans le contexte actuel de l'internet, c'est-à-dire en respectant le paradigme TCP -friendly. On a alors réfléchi au problème du contrôle de congestion dans le contexte plus général des réseaux best effort. Ceci nous a conduit à redéfinir la notion de congestion, définir les propriétés requises par un protocole de contrôle de congestion idéal et définir un nouveau paradigme pour la conception de protocoles de contrôle de congestion presque idéaux. On a introduit à cet effet le paradigme Fair Scheduler (FS). L'approche que l'on a utilisée pour définir ce nouveau paradigme est purement formelle. Pour valider cette approche théorique, on a conçu grâce au paradigme FS un nouveau protocole de contrôle de congestion multipoint à couches cumulatives et orienté récepteur : PLM, qui est capable de suivre les évolutions de la bande passante disponible sans aucune perte induite, même dans un environnement autosimilaire et multifractal. PLM surpasse RLM et RLC et valide le paradigme FS. Comme ce paradigme permet de concevoir des protocoles de contrôle de congestion multipoints et point à point, on a défini une nouvelle politique d'allocation de la bande passante entre flux multipoints et flux point à point. Cette politique, appelée LogRD, permet d'améliorer considérablement la satisfaction des utilisateurs multipoints sans nuire aux utilisateurs point à point.

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Zhang, Cuiyu. "NANOSTRUCTURES OF BENT-CORE LIQUID CRYSTALS - TRANSMISSION ELECTRON MICROSCOPY, X-RAY AND POLARIZING MICROSCOPY STUDIES." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1427495895.

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Aichert, André [Verfasser], Andreas [Akademischer Betreuer] Maier, Andreas [Gutachter] Maier, Harald [Gutachter] Köstler, Christoph [Gutachter] Bert, and Elmar [Gutachter] Nöth. "Epipolar Consistency in Transmission Imaging / André Aichert ; Gutachter: Andreas Maier, Harald Köstler, Christoph Bert, Elmar Nöth ; Betreuer: Andreas Maier." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2020. http://d-nb.info/1211557529/34.

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Santos, Bruno Sávio Boghossian dos. "Análise dinâmica de transmissões por correia serpentina e autotensionador." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265552.

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Orientador: Robson Pederiva Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica Made available in DSpace on 2018-08-16T15:55:46Z (GMT). No. of bitstreams: 1 Santos_BrunoSavioBoghossiandos_M.pdf: 1516247 bytes, checksum: 56409e552f694a7e6380abecffa30505 (MD5) Previous issue date: 2010 Resumo: O acoplamento entre os movimentos de rotação do braço do tensionador e os movimentos transversais dos tramos de correia adjacentes à polia do tensionador é investigado neste trabalho. As equações de movimento de um sistema composto por três polias, correia serpentina e um autotensionador são derivadas a partir do Princípio de Hamilton. Estas equações formam a base para as análises do equilíbrio e vibração linear. Dois métodos são descritos para a solução das equações do equilíbrio. A solução numérica converte rapidamente e fornece a base para a análise da vibração linear. A solução linear aproximada fornece uma indicação da efetividade do design do tensionador, ou seja, sua capacidade de manter a tensão de tração constante, medida a partir da constante de suporte desenvolvida nesta análise. Uma solução de forma fechada baseada no método de Holzer é proposta para analisar as vibrações livres. Dois loops de iteração são utilizados na solução. Um loop interno para a estrutura cíclica e um loop externo para o tensionador. A principal conclusão deste estudo é que um acoplamento linear existe entre os movimentos de rotação do braço do tensionador e os movimentos transversais dos tramos de correia adjacentes à polia do tensionador e produzem respostas dinâmicas diferentes de quando o mesmo é desconsiderado. Um aplicativo para a implementação do modelo foi desenvolvido em Visual Basic Abstract: The coupling between the tensioner rotational movement and the transverse movement of the belt spans adjacent to the tensioner pulley is investigated in this study. Hamilton's Principle is used to derive the governing equations of motion which provide the basis for the equilibrium and linear vibration analysis. Two methods are described for solving the equations of equilibrium. The exact, nonlinear, iterative solution converges quickly, and provides the basis for the linear vibration analysis. The approximated solution provides an indication of the system design effectiveness by the tensioner support constant derived in the study. A closed form solution based on the Holzer's method is proposed for solving the linear vibration analysis problem. Two iterations loops are used in the solution. An internal loop for the cyclic structure and an external loop for the tensioner arm. A major conclusion of this study is that linear coupling exists between rotational and transverse vibrations, and often produces different dynamic response than that predicted by ignoring coupling. A software was developed in Visual Basic to implement the model Mestrado Mecanica dos Sólidos e Projeto Mecanico Mestre em Engenharia Mecânica

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Barbosa, Luciana Oliveira. "A transmissão dos valores culturais em versões do conto de fadas "A bela adormecida" em diferentes contemporaneidades." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/14509.

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Made available in DSpace on 2016-04-28T19:34:26Z (GMT). No. of bitstreams: 1 Luciana Oliveira Barbosa.pdf: 2733797 bytes, checksum: cbdd885dfba184ac3749332ee47f6992 (MD5) Previous issue date: 2008-05-05 Secretaria da Educação do Estado de São Paulo This research paper is within the area of Critical Discourse Analysis and deals with different versions (original, translated, adapted and retold) of the fairy tale Sleeping Beauty. Our main goal is to observe cultural changes in this fairy tale occurred in the Brazilian context. We expect to contribute to Brazilian studies of identity through discourse. The specific goals of this work are: to confront different Brazilian versions of the tale Sleeping Beauty to verify the differences that build the fairy tale; to examine social roles that appear in these versions; focus on cultural values that emerge from these social roles represented by the fairy tale s characters in each version, and, search for traces of the Brazilian people in those values. Each one of these goals depend on different contexts. Our methodological procedure consisted in analyzing the content of each version, by episodes, confronting them. The hypothesis that sustains this research is that fairy tales keep similarities to its original version and at the same time they bring changes related to the representation of cultural values attributed by the society to the characters, their roles and to the actions. This hypothesis showed to be adequate once the analysis of the different versions allowed us to realize Brazilian cultural values with historical background, based on an ecclesiastical discourse, with its moral beliefs that determine the functions of social institutions. It was possible also to observe cultural changes related to the characters characteristics, to their actions, their social roles and the interaction among characters. The analysis results indicate that the differences among the versions are influenced mainly by cultural values of the social and historical context that surround its production. The cultural values are dynamic and their change comes from the need to face new problems daily. The different versions of the fairy tale keep the same characters from the original but they come with different attributes and that gives a new signification to their social roles Esta Dissertação está situada na área da Análise Crítica do Discurso e trata do exame de diferentes versões (original, traduzida, adaptada e recontada) do conto de fadas A bela adormecida , a fim de verificar as mudanças culturais em contemporaneidades diferentes da dinâmica cultural do brasileiro , de forma a contribuir para os estudos identitários brasileiros a partir do discurso. Os objetivos específicos são: confrontar diferentes versões brasileiras do conto A bela adormecida no Bosque em busca das diferenças que constroem as histórias de fadas; examinar os diferentes papéis sociais presentes nessas versões; focalizar os valores culturais contidos nos papéis sociais representados pelos personagens e buscar traços culturais do brasileiro presentes nos valores contidos nos papéis sociais em cada versão , dependendo de contemporaneidades distintas. Nesse sentido, o procedimento metodológico consiste em confrontar os conteúdos das diferentes versões e analisar, por episódios, os traços culturais contidos nos contos. A hipótese que sustenta esta pesquisa considera que os contos de fadas mantêm relações com a sua versão original, ao mesmo tempo que apresentam mudanças relativas às representações dos valores atribuídos pela sociedade às personagens, ações e funções. A hipótese de mostrou adequada, uma vez que o exame das diferentes versões de um conto nos propiciou que detectássemos valores culturais brasileiros com raízes históricas, a partir do discurso fundador eclesiástico, com seus valores morais que determinam o funcionamento das instituições sociais e a verificação das mudanças culturais a partir da caracterização das personagens, de suas ações , de suas funções sociais e da interação de papéis. Os resultados obtidos das análises indicam que as diferenças das versões em relação às expressões enunciadas decorrem da seleção feita pelo autor de cada versão, sendo ela guiada pelos valores culturais contidos na contemporaneidade das cognições sociais da época de produção da versão; que os valores culturais são dinâmicos e a sua mudança decorre do fato de se enfrentar no dia a dia problemas novos para serem resolvidos, e ainda que o mesmo ocorre com os papéis sociais da estrutura da sociedade, pois embora as versões mantenham os mesmos personagens do conto de Perrault, os valores atribuídos a eles propiciam uma ressemantização para as relações sociais desses papéis

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Ramli, Nur Ilyani Binti. "Design and development of a low cost heart best monitor device using finger photoplethysmography technique : circuit design and fabrication of a non-invasive heart beat monitoring device that employs reflectance and transmission mode photoplethysmography using parallel port interface and microcontroller PIC16F84A." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7291.

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A low cost Heart Beat Monitoring device (HBMD) for detecting heart beat in beats per minute is presented in this thesis. An optical technique called “Photoplethysmography” is utilized by attaching to the base of the finger for monitoring beat to beat pulsation. Two major design issues addressed in this research is to achieve a strong and accurate PPG signal and simultaneously minimizing physiological artefacts and interference. In order to achieve the aim and objectives of the research, this thesis thoroughly explores two new signal conditioning hardware designs. Firstly is the design and fabrication of a low cost reflectance mode PPG heart monitor using parallel port interfacing and secondly are the design and development of a portable transmission mode PPG heart monitor using microcontroller PIC16F84A and PIC16F87. Both PPG heart monitor design is divided into three phases. First is the detection of weak pulses through the fingertip. The PPG signal is then amplified, filtered and digitized by the signal processing unit. Finally the heart rate is calculated, analyzed and displayed on the computer using parallel port interface and on the liquid crystal display using microcontroller PIC16F87. A comprehensive circuit design and analysis work was implemented verified by Proteus VSM circuit simulations and laboratory experiments. Data is presented from the method comparison study in which heart rates measured with the reflectance mode PPG and portable transmission mode PPG heart monitor were compared with those measured with standard techniques on 13 human subjects. Benchmarking tests with approved pulse oximeter and blood pressure monitor Omron M6 reveals that the PPG heart monitor is comparable to those devices in displaying the heart rate. It is also verified through experiments that both PPG heart monitor design fulfill the objectives, including achieving strong and accurate PPG signal, reduction in physiological artefacts and interference and financially low in cost. As the conclusion, the current version of the reflectance mode PPG and portable transmission mode PPG heart monitor successfully measure heart rates fast and reliably in most subjects in different body position. The PPG heart monitor proposed avoid the need to apply electrodes or other sensors in the correct position which directly minimizes the preparation time drastically. This makes the PPG heart monitor more attractive for heart monitoring purpose and its advantage should be explored further.

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Ramli, Nur Ilyani Binti. "Design and development of a low cost heart best monitor device using finger photoplethysmography technique :|bcircuit design and fabrication of a non-invasive heart beat monitoring device that employs reflectance and transmission mode photoplethysmography using parallel port interface and microcontroller PIC16F84A." Thesis, University of Bradford, 2014. http://hdl.handle.net/10454/7291.

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A low cost Heart Beat Monitoring device (HBMD) for detecting heart beat in beats per minute is presented in this thesis. An optical technique called “Photoplethysmography” is utilized by attaching to the base of the finger for monitoring beat to beat pulsation. Two major design issues addressed in this research is to achieve a strong and accurate PPG signal and simultaneously minimizing physiological artefacts and interference. In order to achieve the aim and objectives of the research, this thesis thoroughly explores two new signal conditioning hardware designs. Firstly is the design and fabrication of a low cost reflectance mode PPG heart monitor using parallel port interfacing and secondly are the design and development of a portable transmission mode PPG heart monitor using microcontroller PIC16F84A and PIC16F87. Both PPG heart monitor design is divided into three phases. First is the detection of weak pulses through the fingertip. The PPG signal is then amplified, filtered and digitized by the signal processing unit. Finally the heart rate is calculated, analyzed and displayed on the computer using parallel port interface and on the liquid crystal display using microcontroller PIC16F87. A comprehensive circuit design and analysis work was implemented verified by Proteus VSM circuit simulations and laboratory experiments. Data is presented from the method comparison study in which heart rates measured with the reflectance mode PPG and portable transmission mode PPG heart monitor were compared with those measured with standard techniques on 13 human subjects. Benchmarking tests with approved pulse oximeter and blood pressure monitor Omron M6 reveals that the PPG heart monitor is comparable to those devices in displaying the heart rate. It is also verified through experiments that both PPG heart monitor design fulfill the objectives, including achieving strong and accurate PPG signal, reduction in physiological artefacts and interference and financially low in cost. As the conclusion, the current version of the reflectance mode PPG and portable transmission mode PPG heart monitor successfully measure heart rates fast and reliably in most subjects in different body position. The PPG heart monitor proposed avoid the need to apply electrodes or other sensors in the correct position which directly minimizes the preparation time drastically. This makes the PPG heart monitor more attractive for heart monitoring purpose and its advantage should be explored further. Ministry of Higher Education Malaysia (MOHE) and Universiti Tun Hussein Onn Malaysia (UTHM)

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BRUYERE, ARNAUD. "Etude des determinants viraux impliques dans la transmission du beet western yellows virus (bwyv) par son vecteur, le puceron myzus persicae." Strasbourg 1, 1997. http://www.theses.fr/1997STR13128.

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Le beet western yellows virus ou bwyv est un luteovirus, qui infecte de tres nombreuses dicotyledones d'interet agronomique et provoque des jaunisses caracteristiques. Ce virus, limite aux tissus phloemiens de la plante hote, est transmis par un puceron, myzus persicae, selon le mode persistant et circulant. La capside de ce virus est constituee de deux proteines : une proteine majeure ou proteine de coque (cp) de 22,5 kda, codee par l'orf 3 et une proteine mineure ou proteine de readthrough (rt) de 74 kda. Cette proteine de rt est exprimee a partir des orf 3 et 5 grace a un mecanisme de translecture du codon de terminaison de l'orf 3, sous forme d'une proteine de fusion entre la proteine de cp et le domaine de rt. Avant mon arrivee au laboratoire, il avait ete montre que cette proteine etait necessaire a la transmission de ce virus par son vecteur. Mon travail de these a consiste a determiner les motifs presents dans cette proteine, impliques dans la transmission. Dans ce but, nous avons cree des mutants du bwyv touches dans la proteine de rt et etudie leur transmissibilite, par differentes methodes. Les resultats obtenus permettent de diviser le domaine de rt en deux sous domaines : (1) la region n-terminale du domaine de rt, tres conservee parmi les luteovirus, qui est strictement necessaire a l'expression et a l'incorporation de la proteine de rt et donc a la transmission du bwyv et intervient egalement dans l'accumulation du virus dans la plante ; (2) la region c-terminale du domaine de rt, peu conservee, qui n'est pas requise a la transmission, mais contient des determinants pour l'apparition des symptomes. Enfin, nous avons montre qu'il existe une relation entre la transmissibilite du bwyv et l'interaction in vitro entre le bwyv et la symbionine (chaperonine de type hsp-60), proteine d'origine endosymbiotique, extraite du puceron vecteur : seuls le bwyv et les mutants transmissibles se lient a la symbionine.

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Hugosson, Conny, Omer Kayani, and Mark Krieg. "Customer focused development of a variable bent-axis pump/motor for open circuit hydrostatic transmissions, e.g. in hydraulic hybrid drives." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200062.

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The paper presents the development methodology of a hydrostatic pump/motor for use in Parker Hannifin’s advanced series hydraulic hybrid transmissions for medium and heavy duty commercial vehicles. With Parker’s established bent-axis pump/motor technology for heavy duty mobile applications as a basis, it describes the main stages of further development and qualification for demanding automotive main drive transmissions. Parker’s APQP based, customer focused product development model was employed for this development which resulted in the variable bent-axis pump/motor C24 for open circuit hydrostatic transmissions. Positive customer results from a large fleet of in-service refuse collection trucks and parcel delivery vans with Parker advanced hydraulic hybrid drive systems using C24 pumps/motors serve as evidence of Parker’s product development model effectiveness. High reliability, good fuel economy, increased productivity and long brake life of the vehicles can directly be traced back to the streamlined, front-loaded and iterative development model.

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Lima, Alessandra Silva. "Avaliação da atenção a gestantes, na prevenção da transmissão vertical do vírus HIV, no distrito leste de Belo Horizonte." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/GCPA-73APVD.

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The project analyzed the attention to the pregnant woman offered in the health basic attention in the East District of Belo Horizonte city, and actions aimed to control and prevent mother-to-child transmission of HIV. It has been discussed the permanence of HIV vertical transmission significant rates in the validity of technologies adjusted for its prevention. In spite of the Health Ministry delivery anti-retroviral therapy to pregnant woman and newborn that results in lower risks to infectious the child, the use of anti-retrovirals during the pregnancy does not contemplate all the HIV positive pregnant women. This is evidenced by mother-to-child transmission of HIV significant rates. An analysis of the healthy basic attention professionals speeches that follow the pregnant women and the analysis of SISPRENATAL and SINAN data bases has identified functional, economic, physical and cultural limits. This problems are strongly related to the early ingress of pregnant women and receiving the therapeutic on time. The managers involvement, the professionals qualification and intersectorial measurements involving the community are essentials for the purpose action allowing adequate intervention in the mother/child binomial to make possible the effective prevention of vertical transmission of HIV in the health basic units. O projeto analisou a atenção à gestante ofertada na rede básica de saúde do Distrito Leste do município de Belo Horizonte e as ações direcionadas ao controle e à prevenção da transmissão materno-infantil do HIV. Foi discutida a permanência de taxas significativas de transmissão vertical do HIV na vigência de tecnologias adequadas para a sua prevenção. A terapia anti-retroviral, fornecida de forma gratuita pelo Ministério da Saúde para a gestante e seu recém-nascido, resulta em menores riscos de infecção da criança. No entanto, é constatado que o uso de anti-retrovirais durante a gestação não contempla todas as gestantes HIV positivas, o que pode ser evidenciado por taxas de transmissão materno-infantil do HIV ainda significativas. Por meio da análise dos discursos dos profissionais da rede básica que realizam o atendimento às gestantes e da análise dos bancos de dados Sisprenatal e Sinan, foram identificados entraves de ordem funcional, econômica, física e cultural, que se relacionam diretamente aos problemas observados na captação precoce de gestantes e na instituição da terapêutica em tempo adequado. O envolvimento dos gestores, a capacitação dos profissionais e medidas intersetoriais que envolvam a comunidade são essenciais para o correto direcionamento de ações que permitam intervir adequadamente sobre o binômio mãe-filho, possibilitando a prevenção efetiva da transmissão vertical do HIV nas unidades básicas de saúde.

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Gonçalves, Caroline Macedo. "Diferenças na variação da competência vetorial entre nove populações de Aedes aegypti do munícipio de Belo Horizonte, Minas Gerais, ao Dengue virus 2." s.n, 2014. https://www.arca.fiocruz.br/handle/icict/9953.

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Submitted by Nuzia Santos (nuzia@cpqrr.fiocruz.br) on 2015-04-10T17:01:38Z No. of bitstreams: 1 Tese_BCM_CarolineMacedoGoncalves-pdf.pdf: 1566062 bytes, checksum: e805bc24ca1900f82d5004ef6cd9058a (MD5) Approved for entry into archive by Nuzia Santos (nuzia@cpqrr.fiocruz.br) on 2015-04-10T17:01:48Z (GMT) No. of bitstreams: 1 Tese_BCM_CarolineMacedoGoncalves-pdf.pdf: 1566062 bytes, checksum: e805bc24ca1900f82d5004ef6cd9058a (MD5) Approved for entry into archive by Nuzia Santos (nuzia@cpqrr.fiocruz.br) on 2015-04-10T17:02:18Z (GMT) No. of bitstreams: 1 Tese_BCM_CarolineMacedoGoncalves-pdf.pdf: 1566062 bytes, checksum: e805bc24ca1900f82d5004ef6cd9058a (MD5) Made available in DSpace on 2015-04-10T17:02:18Z (GMT). No. of bitstreams: 1 Tese_BCM_CarolineMacedoGoncalves-pdf.pdf: 1566062 bytes, checksum: e805bc24ca1900f82d5004ef6cd9058a (MD5) Previous issue date: 2014 Fundação Oswaldo Cruz. Centro de Pesquisa René Rachou. Belo Horizonte, MG, Brasil No Brasil, as epidemias de dengue ainda estão difundidas por todo o país. Além da falta de conhecimento de como os surtos da doença são capazes de iniciar e sustentar o seu ciclo de transmissão, existem poucos estudos avaliando a habilidade das populações brasileiras de A. aegypti para transmitir o vírus. O objetivo do nosso estudo foi comparar a susceptibilidade de A. aegypti capturados nas nove regionais de Belo Horizonte, ao DENV-2, nos anos de 2009 e 2011. Para tal finalidade, parâmetros como a taxa de infecção (IR), competência vetorial (CV) e a taxa de infeção disseminada (DIR) foram determinadas. Os ovos dos A. aegypti de cada regional foram coletadas separadamente e colonizados em um insetário. As fêmeas adultas foram infectadas experimentalmente com DENV-2 e o vírus foi detectado através da RT-qPCR nas amostras dos corpos e cabeças dos mosquitos. Os dados foram analisados através do programa estatístico Social Sciences – versão 17. A IR variou de 40% a 82,5% em 2009 e de 60% a 100% em 2011. A CV variou de 25% a 77,5% em 2009 e de 25% a 80% em 2011. Já a DIR oscilou de 68,7% a 100% em 2009 e 38,4% a 86,8% em 2011. Os resultados foram avaliados por um modelo logístico utilizando IR como co-variável. Em 2009, as regionais Norte, Barreiro, Centro-Sul e Venda Nova mostraram uma forte associação. Em 2011, uma forte associação foi observada entre as regionais Centro-Sul, Venda Nova, Oeste e Nordeste. Utilizando a competência vetorial com co-variável, em 2009, as regionais Centro-Sul e Venda Nova apresentaram associação mais relevante. Já em 2011, as regionais Centro-Sul, Venda Nova e Barreiro apresentaram associação significativa. Quando os dados de DIR foram analisados pelos modelos de regressão logística, Pampulha, Centro-Sul, Venda Nova, Oeste, Nordeste e Leste 2009), bem como, Centro-Sul, Venda Nova e Oeste (2011) foram as regionais que apresentaram a associação mais forte. Concluí-se que as populações de A. aegypti de Belo Horizonte exibiram ampla variação na sua competência vetorial para transmitir DENV-2. Por isso, dados e estratégias de controle do vetor, de cada uma das regionais, precisam estar disponíveis para os órgãos competentes. Análises futuras precisam ser desenvolvidas para um melhor entendimento das razões pelas quais ocorre esta grande variabilidade na CV e como estes parâmetros se correlacionam com os achados epidemiológicos dos anos seguintes. In Brazil, dengue epidemics are still diffusing throughout the country and it is unclear if outbreaks may initiate a sustainable transmission cycle. There are few studies evaluating the ability of Brazilian Aedes aegypti populations to transmit the virus. The aim of this study was to compare the DENV susceptibility of field-captured Ae. Aegypti populations from nine distinct geographic areas of the city of Belo Horizonte in 2009 and 2011. Parameters as Infection Rate (IR), Vector Competence (VC) and Disseminated Infection rate (DIR) were determined. Aedes aegypti eggs from each region were separately collected and hatched in an insectary. Adult females were experimentally infected with DENV-2 and the virus was detected by qPCR in body and head samples. Data were analyzed with the Statistical Package for the Social Sciences version 17. IR varied from 40% to 82.5% in 2009 and 60% to 100% in 2011. VC ranged from 25% to 77.5% in 2009 and 25% to 80% in 2011. DIR oscillated from 68.7% to 100% in 2009 and 38.4% to 86.8 in 2011. The results were evaluated by a logistic model using IR as covariate. In 2009, North, Barreiro, Central South and Venda Nova showed the strongest association. In 2011, the same was observed for Central South, Venda Nova, West and Northeast regions. Using VC as covariate, in 2009, Central South and Venda Nova showed the most relevant association. In 2011, Central South, Venda Nova and Barreiro presented the most revelation association. When DIR data were analyzed by logistic regression models, Pampulha, Central South, Venda Nova, West, Northeast and East (2009) as well as Central South, Venda Nova and West (2011) were the districts showing the strongest association.We conclude that A. aegypti populations from Belo Horizonte exhibit wide variation in vector competence to transmit dengue. Because of it, vector control strategies should match the available data for each region. Further analysis should be conducted to better understand the reasons for this large variability of vector competence and how these parameters correlate with epidemiological findings in the following years.

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39

Linder, Sophia [Verfasser], and Bela [Akademischer Betreuer] Szabo. "Klärung des Wirkmechanismus des Cannabinoid-Rezeptor-Antagonisten Rimonabant auf die GABAerge synaptische Transmission zwischen Interneuronen und Purkinjezellen im Cerebellum / Sophia Linder ; Betreuer: Bela Szabo." Freiburg : Albert-Ludwigs-Universität Freiburg, 2017. http://d-nb.info/112692086X/34.

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Nozaki, Denise Nakada [UNESP]. "Estudos biológicos e moleculares de begomovirus infectando pimentão (Capsicum annuum) no Estado de São Paulo." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/105407.

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Made available in DSpace on 2014-06-11T19:34:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-01-23Bitstream added on 2014-06-13T21:06:56Z : No. of bitstreams: 1 nozaki_dn_dr_botfca.pdf: 1542379 bytes, checksum: 590b28b89a75aa5cd0e92315447c603f (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Os vírus pertencentes ao gênero Begomovirus da família Geminiviridae são transmitidos pela mosca-branca Bemisia tabaci Gennadius, atualmente constituem um dos problemas fitossanitários mais sérios em diversas culturas. A mosca-branca encontra-se disseminada em todas as principais regiões produtoras de hortaliças do Brasil. No estado de São Paulo, em 2005, plantas de pimentão mostrando sintomas de deformação dos frutos, folhas e mosaico foliar, apresentaram-se infectadas por begomovírus. Até então, no Brasil, a infecção de pimentão por vírus deste gênero havia sido verificada apenas nos estados de Pernambuco e Bahia, no ano de 1997. Amostras de plantas de pimentão foram coletadas nos campos de produção localizados nos municípios de Paranapanema, Piraju, Alvinlândia, Ubirajara, Elias Fausto, Mogi Guaçu, Paulínia e Botucatu, no período de novembro de 2004 a maio de 2006, com finalidade de detecção e verificar a variabilidade genética dos begomovírus infectando esta cultura. A detecção de begomovírus foi realizada por meio de PCR com oligonucleotídeos universais e seqüenciamento de parte da região codificadora para a proteína capsidial. Do total de 228 plantas coletadas, foram encontradas 30 amostras positivas de begomovírus, sendo que seqüências de 23 isolados apresentaram uma identidade de nucleotídeos de 98 a 100% com o Tomato severe rugose virus (ToSRV) e dois isolados, um proveniente da região de Alvinlândia e outro de Mogi Guaçu, apresentaram maior identidade (98 e 95% respectivamente) com a provável espécie Tomato yellow vein streak virus (ToYVSV). O DNA-A do isolado ToSRV[PJU] coletado de pimentão Lilac da região de Pirajú apresentou identidade de nucleotídeos de 99% com outro isolado de ToSRV (DQ207749) proveniente de pimenta e 97% com um isolado de ToSRV (AY029750) proveniente de tomate... The viruses belonging to the genus Begomovirus, of the family Geminiviridae, are transmitted by the whitefly Bemisia tabaci Gennadius, and considered one of the most important fitossanitary problems for several crops. The whitefly is disseminated throughout the country. In São Paulo State, 2005, pepper plants showing fruits deformations, and mosaic on the leaves were infected by begomovirus. Until then in Brazil, the infection of begomovirus in pepper was only reported in 1997, in Pernambuco and Bahia States. Pepper plants were collected in Paranapanema, Piraju, Alvinlândia, Ubirajara, Elias Fausto, Mogi Guaçu, Paulínia and Botucatu, in the period of November of 2004 to May of 2006, with the aim to study the genetic variability of the begomovirus infecting this culture. The begomovirus were detected by PCR using universal oligonucleotídeos and the coat protein region was sequenced. On the total of 228 samples, they were found 30 positive samples of begomovírus, and sequences of 23 isolated presented nucleotides identies of 98 to 100% with Tomato severe rugose virus (ToSRV), while two isolates, one of Alvinlândia and another of Mogi Guaçu, showed identity highest nucleotide (98 and 95% respectively) with the tentative species Tomato yellow vein streak virus (ToYVSV). The nucleotide sequence of the DNA-A of ToSRV[PJU] from pepper cv. Lilac of Pirajú has 99% nucleotide identies with other isolate of ToSRV (DQ207749) collected from pepper and 97% with an isolate of ToSRV (AY029750) from tomato. The sequence of the DNA-B revealed identity of 98% with the DNA-B of ToRMV (AF291706) from Triângulo Mineiro, Minas Gerais and 95% with ToSRV (AY029751). Sap-transmission was verified for Nicandra physaloides and pepper Magda' using infected N. benthamiana as source. By whitefly the virus was transmitted to Lycopersicum esculentum... (Complete abstract click electronic access below)

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Santiago, Maria Cristina. "Avaliação da implantação do programa de distribuição de fórmula láctea infantil na cidade de belo horizonte, mg: repercussão sobre o ganho de peso do recém-nascido exposto ao vírus HIV." reponame:Repositório Institucional da FIOCRUZ, 2006. https://www.arca.fiocruz.br/handle/icict/5039.

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Made available in DSpace on 2012-09-06T01:11:52Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 874.pdf: 812774 bytes, checksum: 0833368077d2f586ec0301bcae7bb6d5 (MD5) Previous issue date: 2006 (...) O objetivo geral deste estudo foi avaliar a implantação das recomendações do PNM, o Programa de Distribuição da Fórmula Láctea Infantil (FL), no Centro de Treinamento e Referência em Doenças Infecciosas e Parasitárias Orestes Diniz -CTR/DIP, na cidade de Belo Horizonte, MG, no ano de 2005. Foi realizada uma avaliação de implantação, da distribuição da FL, utilizando o estudo de caso único, para operacionalizar o Modelo Teórico de Avaliação, com abordagem quali-quantitativa. Foi selecionado como caso o município de Belo Horizonte, MG, e a unidade de análise o CTR/DIP, por ser o único serviço responsável pela distribuição da FL às crianças expostas no município. Como fontes de evidências foram considerados os profissionais de saúde da SMS e do CRT/DIP, as mães matriculadas no serviço, no período de janeiro a dezembro de 2005. As fontes de dados secundários foram: prontuários de atendimento médico das crianças nascidas no período novembro de 2004 a novembro de 2005, e registradas no serviço, a fim de contemplar todas as crianças que se utilizaram da FL no ano de 2005; foram utilizados os dados socioeconômicos e da AIDS disponíveis no Datasus, além de planilhas de entrega e distribuição da FL no CTR/DIP e os dados de repasse financeiro do Fundo a Fundo. Os tipos de coleta de dados foram: entrevistas semi-dirigidas, questionários e observação. O critério de inclusão dos profissionais foi ter a especialidade clínica de infectologista pediátrica ou o profissional de saúde cuidando diretamente da criança exposta ao HIV, contando com a participação espontânea; das mães que levavam seus filhos para o atendimento e para buscarem a FL, sendo consideradas informantes-chave, além dos dados de prontuários das crianças atendidas no ano de 2005. Não houve critérios de exclusão, uma vez que se enfocou a participação espontânea do informante nesta pesquisa.

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Nozaki, Denise Nakada 1972. "Estudos biológicos e moleculares de begomovirus infectando pimentão (Capsicum annuum) no Estado de São Paulo /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/105407.

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Resumo: Os vírus pertencentes ao gênero Begomovirus da família Geminiviridae são transmitidos pela mosca-branca Bemisia tabaci Gennadius, atualmente constituem um dos problemas fitossanitários mais sérios em diversas culturas. A mosca-branca encontra-se disseminada em todas as principais regiões produtoras de hortaliças do Brasil. No estado de São Paulo, em 2005, plantas de pimentão mostrando sintomas de deformação dos frutos, folhas e mosaico foliar, apresentaram-se infectadas por begomovírus. Até então, no Brasil, a infecção de pimentão por vírus deste gênero havia sido verificada apenas nos estados de Pernambuco e Bahia, no ano de 1997. Amostras de plantas de pimentão foram coletadas nos campos de produção localizados nos municípios de Paranapanema, Piraju, Alvinlândia, Ubirajara, Elias Fausto, Mogi Guaçu, Paulínia e Botucatu, no período de novembro de 2004 a maio de 2006, com finalidade de detecção e verificar a variabilidade genética dos begomovírus infectando esta cultura. A detecção de begomovírus foi realizada por meio de PCR com oligonucleotídeos universais e seqüenciamento de parte da região codificadora para a proteína capsidial. Do total de 228 plantas coletadas, foram encontradas 30 amostras positivas de begomovírus, sendo que seqüências de 23 isolados apresentaram uma identidade de nucleotídeos de 98 a 100% com o Tomato severe rugose virus (ToSRV) e dois isolados, um proveniente da região de Alvinlândia e outro de Mogi Guaçu, apresentaram maior identidade (98 e 95% respectivamente) com a provável espécie Tomato yellow vein streak virus (ToYVSV). O DNA-A do isolado ToSRV[PJU] coletado de pimentão Lilac da região de Pirajú apresentou identidade de nucleotídeos de 99% com outro isolado de ToSRV (DQ207749) proveniente de pimenta e 97% com um isolado de ToSRV (AY029750) proveniente de tomate... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: The viruses belonging to the genus Begomovirus, of the family Geminiviridae, are transmitted by the whitefly Bemisia tabaci Gennadius, and considered one of the most important fitossanitary problems for several crops. The whitefly is disseminated throughout the country. In São Paulo State, 2005, pepper plants showing fruits deformations, and mosaic on the leaves were infected by begomovirus. Until then in Brazil, the infection of begomovirus in pepper was only reported in 1997, in Pernambuco and Bahia States. Pepper plants were collected in Paranapanema, Piraju, Alvinlândia, Ubirajara, Elias Fausto, Mogi Guaçu, Paulínia and Botucatu, in the period of November of 2004 to May of 2006, with the aim to study the genetic variability of the begomovirus infecting this culture. The begomovirus were detected by PCR using universal oligonucleotídeos and the coat protein region was sequenced. On the total of 228 samples, they were found 30 positive samples of begomovírus, and sequences of 23 isolated presented nucleotides identies of 98 to 100% with Tomato severe rugose virus (ToSRV), while two isolates, one of Alvinlândia and another of Mogi Guaçu, showed identity highest nucleotide (98 and 95% respectively) with the tentative species Tomato yellow vein streak virus (ToYVSV). The nucleotide sequence of the DNA-A of ToSRV[PJU] from pepper cv. Lilac of Pirajú has 99% nucleotide identies with other isolate of ToSRV (DQ207749) collected from pepper and 97% with an isolate of ToSRV (AY029750) from tomato. The sequence of the DNA-B revealed identity of 98% with the DNA-B of ToRMV (AF291706) from Triângulo Mineiro, Minas Gerais and 95% with ToSRV (AY029751). Sap-transmission was verified for Nicandra physaloides and pepper Magda' using infected N. benthamiana as source. By whitefly the virus was transmitted to Lycopersicum esculentum... (Complete abstract click electronic access below) Orientador: Marcelo Agenor Pavan Coorientador: Renate Krause Sakate Banca: Antonio Carlos Maringoni Banca: Murilo Francisco Zerbini Junior Banca: Romulo Fujito Kobori Banca: Valdir Atsushi Yuki Doutor

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43

Lemaire, Olivier. "Contribution a l'etude des proprietes biologiques des rna du virus de la rhizomanie (beet necrotic yellow vein virus) et de leur role dans l'etiologie de la maladie." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13115.

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44

Bariteau, Jean-Marc. "Etude et réalisation d'anneaux résonnants en optique intégrée." Grenoble INPG, 1989. http://www.theses.fr/1989INPG0068.

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La technologie optique integree sur substrat silicium permet la realisation d'un microguide d'ondes en anneau couple a des microguides rectilignes formant ainsi une cavite resonante. Cette etude apporte des solutions theoriques et de premiers resultats experimentaux pour cet interferometre integre. Une presentation des resonances observables par interferences a ondes multiples est donnee puis l'influence des divers parametres sur les pics de resonance est etudiee. Une evaluation des pertes dues a la courbure de ces microguides est effectuee et le couplage entre microguides est calcule par la methode de perturbation. Les parametres technologiques utilisables sont ensuite determines pour differents rayons d'anneau et les caracteristiques de resonance des anneaux realises sont indiquees ainsi que les valeurs de pertes et de couplage qui s'en deduisent

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45

Fournier, Etienne. "Protocole de diagnostic des entraînements asynchrones par références : application à la détection des déséquilibres mécaniques et des défauts de courroies." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/15546/1/E_Fournier.pdf.

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Les applications entrainées par des moteurs asynchrones consomment à elles seules la majorité de l’énergie électrique utilisée dans le secteur industriel. Des défauts, majoritairement d’origine mécanique, sont susceptibles de se développer au cours du fonctionnement de ces systèmes et rendent nécessaires la mise en place d’une maintenance souvent onéreuse. Afin de réduire ces coûts et d’optimiser la disponibilité des matériels, des méthodes de diagnostic peuvent être développées afin de détecter au plus tôt l’apparition d’un défaut. Cependant, la fiabilité de ces algorithmes et l’automatisation du diagnostic sont complexifiées par la diversité des systèmes alimentés par les variateurs de vitesse industriels ainsi que par le changement de leur point de fonctionnement. Afin de répondre à ces problématiques, un protocole de diagnostic permettant de réaliser une détection sensible et robuste des défaillances mécaniques est développé dans ce travail. Cette méthode consiste à segmenter le plan couple-vitesse du moteur surveillé et à réaliser des références statistiques caractérisant son fonctionnement sain sur chacune des zones de fonctionnement. Des indicateurs de défaut peuvent ensuite être définis statistiquement afin de quantifier l’écart du système vis-à-vis de son comportement sain. Ces indicateurs sont ainsi indépendants du système surveillé et de son point de fonctionnement. Les principales applications ciblées par ce protocole sont les systèmes de compression, de pompage et de ventilation qui représentent une part importante de l’énergie électrique consommée dans le secteur industriel. Le protocole de diagnostic développé dans cette étude est validé expérimentalement dans le cadre de la détection de différentes niveaux de déséquilibre mécanique mais également pour la surveillance d’un système de transmission de type poulies-courroies. De plus, les campagnes expérimentales sont effectuées sur plusieurs systèmes électromécaniques dont les propriétés sont foncièrement différentes afin de valider les performances de normalisation de ce protocole.

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46

Zhao, Yanyan. "Synthesis and characterisation of metal (Fe, Ga, Y) doped alumina and gallium oxide nanostructures." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/20529/1/Yanyan_Zhao_Thesis.pdf.

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It is well known that nanostructures possess unique electronic, optical, magnetic, ferroelectric and piezoelectric properties that are often superior to traditional bulk materials. In particular, one dimensional (1D) nanostructured inorganic materials including nanofibres, nanotubes and nanobelts have attracted considerable attention due to their distinctive geometries, novel physical and chemical properties, combined effects and their applications to numerous areas. Metal ion doping is a promising technique which can be utilized to control the properties of materials by intentionally introducing impurities or defects into a material. γ-Alumina (Al2O3), is one of the most important oxides due to its high surface area, mesoporous properties, chemical and thermal properties and its broad applications in adsorbents, composite materials, ceramics, catalysts and catalyst supports. γ-Alumina has been studied intensively over a long period of time. Recently, considerable work has been carried out on the synthesis of 1D γ-alumina nanostructures under various hydrothermal conditions; however, research on the doping of alumina nanostructures has not been forthcoming. Boehmite (γ-AlOOH) is a crucial precursor for the preparation of γ-Alumina and the morphology and size of the resultant alumina can be manipulated by controlling the growth of AlOOH. Gallium (Ga) is in the same group in the periodic table as aluminum. β-Gallium (III) oxide (β-Ga2O3), a wide band gap semiconductor, has long been known to exhibit conduction, luminescence and catalytic properties. Numerous techniques have been employed on the synthesis of gallium oxide in the early research. However, these techniques are plagued by inevitable problems. It is of great interest to explore the synthesis of gallium oxide via a low temperature hydrothermal route, which is economically efficient and environmentally friendly. The overall objectives of this study were: 1) the investigation of the effect of dopants on the morphology, size and properties of metal ion doped 1D alumina nanostructures by introducing dopant to the AlOOH structure; 2) the investigation of impacts of hydrothermal conditions and surfactants on the crystal growth of gallium oxide nanostructures. To achieve the above objectives, trivalent metal elements such as iron, gallium and yttrium were employed as dopants in the study of doped alumina nanostructures. In addition, the effect of various parameters that may affect the growth of gallium oxide crystals including temperature, pH, and the experimental procedure as well as different types of surfactants were systematically investigated. The main contributions of this study are: 1) the systematic and in-depth investigation of the crystal growth and the morphology control of iron, gallium and yttrium doped boehmite (AlOOH) under varying hydrothermal conditions, as a result, a new soft-chemistry synthesis route for the preparation of one dimensional alumina/boehmite nanofibres and nanotubes was invented; 2) systematic investigation of the crystal growth and morphology and size changes of gallium oxide hydroxide (GaOOH) under varying hydrothermal conditions with and without surfactant at low temperature; We invented a green hydrothermal route for the preparation of α-GaOOH or β-GaOOH micro- to nano-scaled particles; invented a simple hydrothermal route for the direct preparation of γ-Ga2O3 from aqueous media at low temperature without any calcination. The study provided detailed synthesis routes as well as quantitative property data of final products which are necessary for their potential industrial applications in the future. The following are the main areas and findings presented in the study: • Fe doped boehmite nanostructures This work was undertaken at 120ºC using PEO surfactant through a hydrothermal synthesis route by adding fresh iron doped aluminium hydrate at regular intervals of 2 days. The effect of dopant iron, iron percentage and experimental procedure on the morphology and size of boehmite were systematically studied. Iron doped boehmite nanofibres were formed in all samples with iron contents no more than 10%. Nanosheets and nanotubes together with an iron rich phase were formed in 20% iron doped boehmite sample. A change in synthesis procedure resulted in the formation of hematite large crystals. The resultant nanomaterials were characterized by a combination of XRD, TEM, EDX, SAED and N2 adsorption analysis. • Growth of pure boehmite nanofibres/nanotubes The growth of pure boehmite nanofibres/nanotubes under different hydrothermal conditions at 100ºC with and without PEO surfactant was systematically studied to provide further information for the following studies of the growth of Ga and Y doped boehmite. Results showed that adding fresh aluminium hydrate precipitate in a regular interval resulted in the formation of a mixture of long and short 1D boehmite nanostructures rather than the formation of relatively longer nanofibres/nanotubes. The detailed discussion and mechanism on the growth of boehmite nanostructure were presented. The resultant boehmite samples were also characterized by N2 adsorption to provide further information on the surface properties to support the proposed mechanism. • Ga doped boehmite nanostructures Based on this study on the growth of pure boehmite nanofibre/nanotubes, gallium doped boehmite nanotubes were prepared via hydrothermal treatment at 100ºC in the presence of PEO surfactant without adding any fresh aluminium hydrate precipitate during the hydrothermal treatment. The effect of dopant gallium, gallium percentage, temperature and experimental procedure on the morphology and size of boehmite was systematically studied. Various morphologies of boehmite nanostructures were formed with the increase in the doping gallium content and the change in synthesis procedure. The resultant gallium doped boehmite nanostructures were characterized by TEM, XRD, EDX, SAED, N2 adsorption and TGA. • Y doped boehmite nanostructures Following the same synthesis route as that for gallium doped boehmite, yttrium doped boehmite nanostructures were prepared at 100ºC in the presence of PEO surfactant. From the study on iron and gallium doped boehmite nanostructures, it was noted both iron and gallium cannot grow with boehmite nanostructure if iron nitrate and gallium nitrate were not mixed with aluminium nitrate before dissolving in water, in particular, gallium and aluminium are 100% miscible. Therefore, it’s not necessary to study the mixing procedure or synthesis route on the formation of yttrium doped boehmite nanostructures in this work. The effect of dopant yttrium, yttrium percentage, temperature and surfactant on the morphology and size of boehmite were systematically studied. Nanofibres were formed in all samples with varying doped Y% treated at 100ºC; large Y(OH)3 crystals were also formed at high doping Y percentage. Treatment at elevated temperatures resulted in remarkable changes in size and morphology for samples with the same doping Y content. The resultant yttrium doped boehmite nanostructures were characterized by TEM, XRD, EDX, SAED, N2 adsorption and TGA. • The synthesis of Gallium oxide hydroxide and gallium oxide with surfactant In this study, the growth of gallium oxide hydroxide under various hydrothermal conditions in the presence of different types of surfactants was systematically studied. Nano- to micro-sized gallium oxide hydroxide was prepared. The effect of surfactant and synthesis procedure on the morphology of the resultant gallium oxide hydroxide was studied. β-gallium oxide nanorods were derived from gallium oxide hydroxide by calcination at 900ºC and the initial morphology was retained. γ-gallium oxide nanotubes up to 65 nm in length, with internal and external diameters of around 0.8 and 3.0 nm, were synthesized directly in solution with and without surfactant. The resultant nano- to micro-sized structures were characterized by XRD, TEM, SAED, EDX and N2 adsorption. • The synthesis of gallium oxide hydroxide without surfactant The aim of this study is to explore a green synthesis route for the preparation of gallium oxide hydroxide or gallium oxide via hydrothermal treatment at low temperature. Micro to nano sized GaOOH nanorods and particles were prepared under varying hydrothermal conditions without any surfactant. The resultant GaOOH nanomaterials were characterized by XRD, TEM, SAED, EDX, TG and FT-IR. The growth mechanism of GaOOH crystals was proposed.

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47

Zhao, Yanyan. "Synthesis and characterisation of metal (Fe, Ga, Y) doped alumina and gallium oxide nanostructures." Queensland University of Technology, 2008. http://eprints.qut.edu.au/20529/.

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Abstract:

It is well known that nanostructures possess unique electronic, optical, magnetic, ferroelectric and piezoelectric properties that are often superior to traditional bulk materials. In particular, one dimensional (1D) nanostructured inorganic materials including nanofibres, nanotubes and nanobelts have attracted considerable attention due to their distinctive geometries, novel physical and chemical properties, combined effects and their applications to numerous areas. Metal ion doping is a promising technique which can be utilized to control the properties of materials by intentionally introducing impurities or defects into a material. γ-Alumina (Al2O3), is one of the most important oxides due to its high surface area, mesoporous properties, chemical and thermal properties and its broad applications in adsorbents, composite materials, ceramics, catalysts and catalyst supports. γ-Alumina has been studied intensively over a long period of time. Recently, considerable work has been carried out on the synthesis of 1D γ-alumina nanostructures under various hydrothermal conditions; however, research on the doping of alumina nanostructures has not been forthcoming. Boehmite (γ-AlOOH) is a crucial precursor for the preparation of γ-Alumina and the morphology and size of the resultant alumina can be manipulated by controlling the growth of AlOOH. Gallium (Ga) is in the same group in the periodic table as aluminum. β-Gallium (III) oxide (β-Ga2O3), a wide band gap semiconductor, has long been known to exhibit conduction, luminescence and catalytic properties. Numerous techniques have been employed on the synthesis of gallium oxide in the early research. However, these techniques are plagued by inevitable problems. It is of great interest to explore the synthesis of gallium oxide via a low temperature hydrothermal route, which is economically efficient and environmentally friendly. The overall objectives of this study were: 1) the investigation of the effect of dopants on the morphology, size and properties of metal ion doped 1D alumina nanostructures by introducing dopant to the AlOOH structure; 2) the investigation of impacts of hydrothermal conditions and surfactants on the crystal growth of gallium oxide nanostructures. To achieve the above objectives, trivalent metal elements such as iron, gallium and yttrium were employed as dopants in the study of doped alumina nanostructures. In addition, the effect of various parameters that may affect the growth of gallium oxide crystals including temperature, pH, and the experimental procedure as well as different types of surfactants were systematically investigated. The main contributions of this study are: 1) the systematic and in-depth investigation of the crystal growth and the morphology control of iron, gallium and yttrium doped boehmite (AlOOH) under varying hydrothermal conditions, as a result, a new soft-chemistry synthesis route for the preparation of one dimensional alumina/boehmite nanofibres and nanotubes was invented; 2) systematic investigation of the crystal growth and morphology and size changes of gallium oxide hydroxide (GaOOH) under varying hydrothermal conditions with and without surfactant at low temperature; We invented a green hydrothermal route for the preparation of α-GaOOH or β-GaOOH micro- to nano-scaled particles; invented a simple hydrothermal route for the direct preparation of γ-Ga2O3 from aqueous media at low temperature without any calcination. The study provided detailed synthesis routes as well as quantitative property data of final products which are necessary for their potential industrial applications in the future. The following are the main areas and findings presented in the study: • Fe doped boehmite nanostructures This work was undertaken at 120ºC using PEO surfactant through a hydrothermal synthesis route by adding fresh iron doped aluminium hydrate at regular intervals of 2 days. The effect of dopant iron, iron percentage and experimental procedure on the morphology and size of boehmite were systematically studied. Iron doped boehmite nanofibres were formed in all samples with iron contents no more than 10%. Nanosheets and nanotubes together with an iron rich phase were formed in 20% iron doped boehmite sample. A change in synthesis procedure resulted in the formation of hematite large crystals. The resultant nanomaterials were characterized by a combination of XRD, TEM, EDX, SAED and N2 adsorption analysis. • Growth of pure boehmite nanofibres/nanotubes The growth of pure boehmite nanofibres/nanotubes under different hydrothermal conditions at 100ºC with and without PEO surfactant was systematically studied to provide further information for the following studies of the growth of Ga and Y doped boehmite. Results showed that adding fresh aluminium hydrate precipitate in a regular interval resulted in the formation of a mixture of long and short 1D boehmite nanostructures rather than the formation of relatively longer nanofibres/nanotubes. The detailed discussion and mechanism on the growth of boehmite nanostructure were presented. The resultant boehmite samples were also characterized by N2 adsorption to provide further information on the surface properties to support the proposed mechanism. • Ga doped boehmite nanostructures Based on this study on the growth of pure boehmite nanofibre/nanotubes, gallium doped boehmite nanotubes were prepared via hydrothermal treatment at 100ºC in the presence of PEO surfactant without adding any fresh aluminium hydrate precipitate during the hydrothermal treatment. The effect of dopant gallium, gallium percentage, temperature and experimental procedure on the morphology and size of boehmite was systematically studied. Various morphologies of boehmite nanostructures were formed with the increase in the doping gallium content and the change in synthesis procedure. The resultant gallium doped boehmite nanostructures were characterized by TEM, XRD, EDX, SAED, N2 adsorption and TGA. • Y doped boehmite nanostructures Following the same synthesis route as that for gallium doped boehmite, yttrium doped boehmite nanostructures were prepared at 100ºC in the presence of PEO surfactant. From the study on iron and gallium doped boehmite nanostructures, it was noted both iron and gallium cannot grow with boehmite nanostructure if iron nitrate and gallium nitrate were not mixed with aluminium nitrate before dissolving in water, in particular, gallium and aluminium are 100% miscible. Therefore, it’s not necessary to study the mixing procedure or synthesis route on the formation of yttrium doped boehmite nanostructures in this work. The effect of dopant yttrium, yttrium percentage, temperature and surfactant on the morphology and size of boehmite were systematically studied. Nanofibres were formed in all samples with varying doped Y% treated at 100ºC; large Y(OH)3 crystals were also formed at high doping Y percentage. Treatment at elevated temperatures resulted in remarkable changes in size and morphology for samples with the same doping Y content. The resultant yttrium doped boehmite nanostructures were characterized by TEM, XRD, EDX, SAED, N2 adsorption and TGA. • The synthesis of Gallium oxide hydroxide and gallium oxide with surfactant In this study, the growth of gallium oxide hydroxide under various hydrothermal conditions in the presence of different types of surfactants was systematically studied. Nano- to micro-sized gallium oxide hydroxide was prepared. The effect of surfactant and synthesis procedure on the morphology of the resultant gallium oxide hydroxide was studied. β-gallium oxide nanorods were derived from gallium oxide hydroxide by calcination at 900ºC and the initial morphology was retained. γ-gallium oxide nanotubes up to 65 nm in length, with internal and external diameters of around 0.8 and 3.0 nm, were synthesized directly in solution with and without surfactant. The resultant nano- to micro-sized structures were characterized by XRD, TEM, SAED, EDX and N2 adsorption. • The synthesis of gallium oxide hydroxide without surfactant The aim of this study is to explore a green synthesis route for the preparation of gallium oxide hydroxide or gallium oxide via hydrothermal treatment at low temperature. Micro to nano sized GaOOH nanorods and particles were prepared under varying hydrothermal conditions without any surfactant. The resultant GaOOH nanomaterials were characterized by XRD, TEM, SAED, EDX, TG and FT-IR. The growth mechanism of GaOOH crystals was proposed.

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48

Daniel, Lisa Maree. "Laponite-supported titania photocatalysts." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16669/3/Lisa_Daniel_Thesis.pdf.

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This thesis describes the synthesis and characterisation of titania photocatalysts for incorporation into a polyethylene film. Monodisperse, anatase-phase titania nanoparticles are prepared and the synthesis conditions necessary for attraction to a laponite clay support are determined. Methods of preventing agglomeration of the laponite system such as the use of a polyethylene oxide surfactant or chemical modification of the laponite plate edges with a dimethyloctyl methoxysilane are also explored. Finally, photocatalytic studies on the laponite-supported titania nanoparticles are performed, and the compatibility and photoactivity of these materials in the polyethylene film are examined.

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49

Daniel, Lisa Maree. "Laponite-supported titania photocatalysts." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16669/.

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Abstract:

This thesis describes the synthesis and characterisation of titania photocatalysts for incorporation into a polyethylene film. Monodisperse, anatase-phase titania nanoparticles are prepared and the synthesis conditions necessary for attraction to a laponite clay support are determined. Methods of preventing agglomeration of the laponite system such as the use of a polyethylene oxide surfactant or chemical modification of the laponite plate edges with a dimethyloctyl methoxysilane are also explored. Finally, photocatalytic studies on the laponite-supported titania nanoparticles are performed, and the compatibility and photoactivity of these materials in the polyethylene film are examined.

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50

LE, COZ SERGE. "La rhizomanie de la betterave sucriere : multiplication du virus et aspects agronomiques de la maladie." Paris 6, 1986. http://www.theses.fr/1986PA066644.

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Les chloroplastes des feuilles de betteraves rhizomaniees sont appauvries en pigments, en proteines, en liquides polaires et leur activite photosynthetique est reduite. Dans les cellules virosees, l'etude ultrastructure montre une association des amas de virus avec le reticulum endoplasmique granuleux. Un protocole pour la preparation de suspensions enrichies en cytosores isoles de polymyxa betae est propose. Le champignon est retrouve a tous les niveaux du sol de quatre parcelles rhizomaniees ou saines de la region de pithiviers. Une terre rhizomaniee reste infectieuse aprese un an et demi de lagune en bassin

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Dissertations / Theses on the topic 'Belt transmission'

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