674 resultados para MOTORS


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Mode of access: Internet.

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signed: Henry Helwig Fenton, Interior of Buick Motor Company, plant no. 1

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"Designed specifically to teach professional industrial personnel the basic considerations in the application of radioisotopes to industrial work."

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Includes index.

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Thesis (Ph.D.)--University of Washington, 2016-06

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Golgi membranes and Golgi-derived vesicles are associated with multiple cytoskeletal proteins and motors, the diversity and distribution of which have not yet been defined. Carrier vesicles were separated from Golgi membranes, using an in vitro budding assay, and different populations of vesicles were separated using sucrose density gradients. Three main populations of vesicles labeled with beta-COP, gamma-adaptin, or p200/myosin II were separated and analyzed for the presence of actin/actin-binding proteins, beta-Actin was bound to Golgi cisternae and to all populations of newly budded vesicles. Centractin was selectively associated with vesicles co-distributing with beta-COP-vesicles, while p200/myosin II (non-muscle myosin IIA) and non-muscle myosin IIB were found on different vesicle populations. Isoforms of the Tm5 tropomyosins were found on selected Golgi-derived vesicles, while other Tm isoforms did not colocalize with Tm5 indicating the association of specialized actin filaments with Golgi-derived vesicles. Golgi-derived vesicles were shown to bind to F-actin polymerized from cytosol with Jasplakinolide. Thus, newly budded, coated vesicles derived from Golgi membranes can bind to actin and are customized for differential interactions with microfilaments by the presence of selective arrays of actin-binding proteins.

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In this paper we consider the co-evolutionary dynamics of IS engagement where episodic change of implementation increasingly occurs within the context of linkages and interdependencies between systems and processes within and across organisations. Although there are many theories that interpret the various motors of change be it lifecycle, teleological, dialectic or evolutionary, our paper attempts to move towards a unifying view of change by studying co-evolutionary dynamics from a complex systems perspective. To understand how systems and organisations co-evolve in practice and how order emerges, or fails to emerge, we adopt complex adaptive systems theory to incorporate evolutionary and teleological motors, and actor-network theory to incorporate dialectic motors. We illustrate this through the analysis of the implementation of a novel academic scheduling system at a large research-intensive Australian university.

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O trabalho proposto é a montar um projeto exploratório funcional que parta da cartografia cognitiva, que é definida como a arte, teoria e técnica de construir mapas do conhecimento, visando com esta cartografia a sua aplicabilidade na estruturação de um conjunto de cursos/saberes da área da Comunicação. Assemelhado ao conceito de mapas conceituais, ou cognitivos, representam o conhecimento organizado e são compostos por conceitos. Este mapas foram desenvolvido a partir da década de setenta por vários pesquisadores. A tese experimento foi montada tendo como base os softwares de relacionamento por temas e interesses dentro de um ambiente de interatividade tridimensional , montado no conceito de arvore do conhecimento relacional. Esta experiência é construída em ambiente tridimensional com uso de softwares 3D que rodam como aplicativos de engines de vídeo games, que são motores gráficos. A base de dados e a interatividade de textos e tarefas é realizada sob a plataforma do MediaWiki, que é o software aberto que roda a Wikipédia. A plataforma de mapas roda dentro de um software MindJet MindManager e do CMAPS. As vídeo conferências são administradas pelo FlashMeeting, de Web conferência. A maioria deles são softwares abertos. Todos operando em sistemas presenciais ou de modulação EAD. A base conceitual está estruturada dentro de uma visão de educação disruptiva, que lança um novo modelo educacional baseado em mapas, visto dentro de uma abordagem de um mundo de múltiplas telas, um mundo da era hiper, um mundo hipermoderno, que tem como base uma cultura da era tecnológica, numa renovação dos conceitos de Cultura, agora revigorados à luz das novas tecnologias e da nova sociedade interligada em rede.

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A trajetória de vida do publicitário, jornalista, contista, novelista, romancista e ensaísta Orígenes Lessa é rica em experiência profissional e conhecimento intelectual na propaganda e na literatura. O objetivo central deste trabalho foi o de resgatar seu itinerário na propaganda, seus valores, as técnicas de publicidade por ele utilizadas, bem como suas contribuições para a evolução da propaganda brasileira. O publicitário, detentor também de ampla produção literária, foi o primeiro presidente da APP Associação dos Profissionais de Propaganda. Trabalhou em uma das primeiras agências de publicidade do Brasil, a Eclética. Começou a atuar em 1928 na multinacional General Motors, depois em agências estrangeiras, como a J.W. Thompson, e em meios de comunicação nacionais, consolidando uma carreira de 57 anos dedicados à publicidade. Adotamos o método de pesquisa histórica buscando os vínculos entre a trajetória pessoal e profissional de Orígenes Lessa e o desenvolvimento da publicidade. Privilegiamos o período das décadas de 20 e 30, época de ativa militância do publicitário na área. Destacamos sua percepção do trabalho do redator publicitário, seus valores, principais trabalhos e as repercussões dos mesmos na sociedade brasileira.(AU)

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Isocyanate cross-linked hydroxy terminated polybutadiene is used as a binder for solid rocket propellant. Rocket motors containing this propellant require a storage life of at least 20 years. During storage it has been found that the important rubbery properties of the binder can be lost due to oxidative cross-linking of the polybutadiene chains. This could cause catastrophic failure when the rocket motor is required. At present the bis-hindered phenol Calco 2246 is used as a thermal oxidative stabiliser, but it's performance is only adequate. This has led to the search for a more efficient stabiliser system. To hasten the evaluation of new antioxidant systems the use of dynamic thermal analysis was investigated. Results showed that a tentative relationship existed between predictions by thermal analysis and the long term oven ageing for simple single antioxidant systems. But for more complex systems containing either autosynergistic or mixed antioxidants no relationship was observed suggesting that results for such an "accelerated" technique cannot be used for the purpose of extrapolation for long term performance. This was attributed to the short time and more aggressive condition used (hjgher temperature and oxygen rich atmosphere in thermal analysis) altering the mechanism of action of the antioxidants and not allowing time for co-operative effect of the combined antioxidant system to form. One potential problem for the binder system is the use of an diisocyanate as a cross-linking agent. This reacts with the hydroxyl hydrogen on the polymer as well as other active hydrogens such as those contained in a number of antioxidants, affecting both cross-linking and antioxidant effectiveness. Studies in this work showed that only antioxidants containing amine moieties have a significant affect on binder preparation, with the phenolic antioxidants not reacting. This is due to the greater nucleophilicity of the amines. Investigation of a range of antioxidant systems, including potentially homo, hetero and autosynergistic systems, has highlighted a number of systems which show considerably greater effectiveness than the currently used antioxidant Calco 2246. The only single antioxidant which showed improvement was the partially unhindered phenol y-Tocopherol. Of the mixed systems combinations of the sulphur containing antioxidants e.g. DLTP with higher levels of chain-breaking antioxidants, especially Calco 2246, were the most promising. Also the homosynergistic mix of an aromatic amine and a phenol was seen to be very effective but the results were inconsistent. This inconsistency could be explained by the method of sample preparation used. It was shown that the efficiency of a number of antioxidant.s could be dramatically improved by the use of ultrasound during the mixing stage of preparation. The reason for this increase in performance is unclear but in the case of the homosynergistic amine/phenol mix both more efficient mixing and/or the production of a novel mechanism of action are suggested

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This thesis reports the development of a reliable method for the prediction of response to electromagnetically induced vibration in large electric machines. The machines of primary interest are DC ship-propulsion motors but much of the work reported has broader significance. The investigation has involved work in five principal areas. (1) The development and use of dynamic substructuring methods. (2) The development of special elements to represent individual machine components. (3) Laboratory scale investigations to establish empirical values for properties which affect machine vibration levels. (4) Experiments on machines on the factory test-bed to provide data for correlation with prediction. (5) Reasoning with regard to the effect of various design features. The limiting factor in producing good models for machines in vibration is the time required for an analysis to take place. Dynamic substructuring methods were adopted early in the project to maximise the efficiency of the analysis. A review of existing substructure- representation and composite-structure assembly methods includes comments on which are most suitable for this application. In three appendices to the main volume methods are presented which were developed by the author to accelerate analyses. Despite significant advances in this area, the limiting factor in machine analyses is still time. The representation of individual machine components was addressed as another means by which the time required for an analysis could be reduced. This has resulted in the development of special elements which are more efficient than their finite-element counterparts. The laboratory scale experiments reported were undertaken to establish empirical values for the properties of three distinct features - lamination stacks, bolted-flange joints in rings and cylinders and the shimmed pole-yoke joint. These are central to the preparation of an accurate machine model. The theoretical methods are tested numerically and correlated with tests on two machines (running and static). A system has been devised with which the general electromagnetic forcing may be split into its most fundamental components. This is used to draw some conclusions about the probable effects of various design features.

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Computer integrated monitoring is a very large area in engineering where on-line, real time data acquisition with the aid of sensors is the solution to many problems in the manufacturing industry as opposed to the old data logging method by graphics analysis. The raw data which is collected this way however is useless in the absence of a proper computerized management system. The transfer of data between the management and the shop floor processes has been impossible in the past unless all the computers in the system were totally compatible with each other. This limits the efficiency of the systems because they get governed by the limitations of the computers. General Motors of U.S.A. have recently started research on a new standard called the Manufacturing Automation Protocol (MAP) which is expected to allow data transfer between different types of computers. This is still in early development stages and also is currently very expensive. This research programme shows how such a shop floor data acquisition system and a complete management system on entirely different computers can be integrated together to form a single system by achieving data transfer communications using a cheaper but a superior alternative to MAP. Standard communication character sets and hardware such as ASCII and UARTs have been used in this method but the technique is so powerful that totally incompatible computers are shown to run different programs (in different languages) simultaneously and yet receive data from each other and process in their own CPUs with no human intervention.

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The bearings in the air motors of modern jet aircraft engines must operate dry in hostile conditions at temperatures up to 500° C, where the thrust races in the actuators operate at temperatures up to 300° C. One of the few metallurgical combinations which can function efficiently under these conditions is martensitic stainless steel on tungsten carbide. The work described was initiated to isolate the wear mechanisms of two such steels in contact with tungsten carbide at temperatures up to 500° C. Experiments were carried out on angular contact bearings similar to these used in service, where both rolling and sliding is present and also for pure sliding conditions using a pin-on-disc apparatus. Wear measurements of the bearings were obtained with wear rates, friction and surface temperatures from the pin-on-disc machine for a series of loads and speeds. Extensive X-ray diffraction analysis was carried out on the wear debris, with also S.E.M. analysis and hardness tests on the worn surfaces along with profilometry measurements of the disc. The oxidational parameters of the steel were obtained from measurements of oxide growth rates by ellipsometry. Three distinct mechanisms of wear were established and the latter two were found to be present in both configurations. These involve an oxidational-abrasive mechanism at loads below 40 N with pin surface temperatures up to about 300 °C, with the mechanism changing to severe wear for higher loads. As the temperature increases a third wear mechanism appears due to transfer of relatively soft oxide films to the steel surface reducing the wear rate. Theoretical K factors were derived and compared with experimental values which were found to be in good agreement for the severe wear mechanism. The pin-on-disc experiments may be useful as a screening test for material selection, without the considerable cost of producing the angular contact bearings.

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A navigation and positioning system for an electric automatic guided vehicle has been designed and implemented on an industrial pallet truck. The system includes an optical sensor mounted on the vehicle, capable of recognizing special markers at a distance of 0.3m. Software implemented in a z-80 microprocessor controls the sensor, performs all data processing and contains the decision making processes necessary for the vehicle to navigate its way to its task location. A second microprocessor is used to control the vehicle's drive motors under instruction from the navigation unit, to accurately position the vehicle at its destination. The sensor reliably recognises markers at vehicle speeds up to 1ms- 1, and the system has been integrated into a multiprocessor controlled wire-guidance system and applied to a prototype vehicle.