Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2006. / Shunt and shuffle in a vehicle drivetrain are two driveability related phenomena responsible for driver discomfort. They are experienced as a sharp jerk (shunt) followed by a series of longitudinal oscillations (shuffle) and are induced by a rapid change in engine torque. The use of drive‐by‐wire throttles in modern day vehicles enables the onboard electronic control unit to manipulate the driver’s torque demand befoe sending a revised torque demand signal to the engine. In this way a feedback control system can be used to ensure that the drivetrain follows the driver’s torque demand as quickly s possible without inducing shunt or shuffle.      In this project a drivetrain model was derived and its parameters experimentally determined. The accuracy of the model was validated using test data from a vehicle, and the conclusion was made that the model was an accurate vehicle simulation tool. A drivetrain controller was then designed and its performance simulated using the vehicle model. The simulations showed that the controller significantly reduced the shunt and shuffle in the drivetrain thereby improving drier comfort.

published_or_final_version / Transport Policy and Planning / Master / Master of Arts in Transport Policy and Planning

No description available.

Thesis (Elec.E)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Wing Hong Lee. / Elec.E

As machine topologies and technologies mature, the fundamental function of the device is honed. Direct drive machines have the potential to launch the renewable energy sector into a new era of large scale, reliable, offshore power generation. With advancements in new technologies, such as superconductivity, the reduction of generator mass due to incorporation of machine and device structures, the continued advancements in component and system reliability; direct drive generators have the ability to outsize geared wind systems and simplify submerged linear and rotary power generation. The research held within this thesis will focus on improving direct drive power take off systems for offshore renewable energy power generation by splitting the area into four parts. The first part will discuss the various methods of energy extraction within the offshore and marine environment. The future of the sector will be discussed, and a forecast of technological advancement and existing reliability issues will be provided based on current data. The second part will focus on drive trains and direct drive generators, assessing the current topologies and suggesting alternatives that may thrive in a variety of large and small offshore renewable machines. The third part investigates the application of novel linear bearings in direct drive systems for offshore and submerged operation. A brief study of the loads found in wave applications will be presented and the testing of several polymer bearing materials will be outlined. The final part will discuss the potential benefits of flooding the airgap of a direct drive generator with sea water for marine applications. Results will be presented from two linear test rigs and the marinisation of devices will conclude the report.

L'étude du comportement des voies ferrées ballastées sous les passages de trains à grandes vitesses est une des recherches les plus importantes dans le domaine des transports. À cause du passage répété de trains à grandes vitesses, des tassements verticaux différentiels sont observés tout au long de la voie ferrée. Ces tassements dépendent de la qualité de la plate-forme, de la vitesse de roulement ainsi que du comportement dynamique de la voie. Ils peuvent menacer le confort et la sécurité des passagers et nécessiter des coûts élevés de maintenance pour rendre la voie à sa géométrie initiale. Pour progresser dans la compréhension du phénomène de tassement, un essai à échelle réduite constitué de trois traverses est proposé. Les traverses sont mises en charge à l'aide de trois vérins hydrauliques fournissant des signaux ayant la forme de la lettre M qui simulent les passages de bogies. Cet essai permet de mesurer plusieurs paramètres tels que les déplacements, les accélérations et les contraintes dans l'éprouvette. Il est modélisé par la méthode des éléments finis avec des comportements élastiques linéaires et avec deux zones différentes de ballast (compactée et non compactée). Les résultats numériques déterminés grâce à un modèle tridimensionnel sont comparés à ceux de la mesure. Le but essentiel de cet essai est d'établir une loi de tassement vertical pour un grand nombre de cycles dépendant d'un paramètre dynamique qui peut être déterminé par le modèle numérique tridimensionnel.

Made available in DSpace on 2015-05-14T12:09:11Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 2630968 bytes, checksum: 7ccfc1bc157dd97f0df36f85ac84db1a (MD5) Previous issue date: 2008-06-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Currently, urban centres are more and more subject to vibration induced by traffic, because of its increasing volume. Among the vibration effects are damage to buildings. In this study, the effects of the vibration produced by suburban trains in buildings was investigated, by taking a railway line with mixed passenger and cargo traffic as a (typical) case study. Measurements were taken, aiming to identify the vibration levels in buildings adjacent to the railway line and which presented visible cracks in their surfaces. The results obtained revealed that vibration levels produced by passenger trains were below the limits which could potentially cause damage. However, simulations performed in order to estimate the vibration levels induced by freight trains evidenced the occurrence of levels greater than those acceptable for the type of buildings investigated. / Atualmente, os centros urbanos estão mais sujeitos à vibração induzida por tráfego, em virtude do aumento do volume deste. Dentre os efeitos da vibração, estão os danos em edificações. Neste estudo, foram investigados os efeitos da vibração produzida pelo tráfego de trens suburbanos em edificações, tomandose como caso (típico) de estudo uma linha férrea com tráfego misto de passageiros e de carga. Medições foram realizadas, visando identificar os níveis de vibração em edificações adjacentes à linha férrea e que apresentavam fissuração visível em suas fachadas. Os resultados obtidos mostraram que os níveis de vibração produzidos pelo tráfego de trens de passageiros apresentaram-se abaixo dos limites que potencialmente causariam dano. Todavia, simulações realizadas para estimar os níveis de vibração induzidos por trens de carga evidenciaram a ocorrência de níveis superiores aos aceitáveis para o tipo de edificações investigadas.

Thesis compares Czech railway passenger transport with Swiss railway transport for the purpose of more effective use of railway transport in domestic and incoming tourism of the Czech Republic. According to chosen standards are analysed Czech Railways and Swiss Railways with respect to quality and variety of provided services, prices, ways of ticket sales, trains and promotion. Research shows how Czech tourists use services of Czech Railways and how they like them.

Brůžková, K.: Trainstations, trains and school. [diploma thesis] Praha 2013 - Charles University, Faculty of Education, art department, 74 p. (Supplements: 6 drawings 65 x 50 cm, 1 concertina book O(b)drazy, 1 book (K. na kolejích), 1 CD) The work is about railway and many pictures of it in art. It contains art projects and theoretical study. The topic is looked from many different views. It's trying to explain, how was the theme taken in different times. Text is divided into three main parts: a) theoretical - about few artists (groups of artists), which had the railway as popular theme of work, mainly art and film b) didactical - contains realised projects, on a secondary grammar school and on a ceramics with younger children c) authorial part - is about my own production, it is divided for three parts: drawings, book and concertina book

Soil-steel composite bridge refers to structures where a buried flexible corrugated steel pipe works in composite action with the surrounding soil. These structures are being increasingly used in road and railway projects as an alternative to standard type bridges, e.g. short- and medium span concrete beam- and portal frame bridges. On account of their economic advantage and short and easy construction operation, soil-steel composite bridges are getting more popular as railway crossings located far from the cities at the heart of the nature. In this research, the dynamic behaviour of soil-steel composite bridges under high-speed train passages is studied. The studied case is a short span soil-steel composite railway bridge located in Märsta close to Stockholm. The behaviour of the bridge is first observed through field measurements in terms of deflections, stresses, and accelerations at several locations on the bridge. The measured responses are then analysed in order to predict the properties of the soil and steel material working in composite action. Subsequently, 2D and 3D finite element models are developed in order to simulate the behaviour of the bridge. The models are calibrated using the field measurements through several parametric studies. The 3D-model also enables estimation of the load distribution, which is found to increase at higher train speeds. An effective width to be used in 2D analyses is proposed. Finally, the response of the bridge is studied under high-speed train models according to Eurocode.