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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The Tower of London icon of early modern English drama /

Deiter, Kristen. January 2005 (has links)
Thesis (Ph. D.)--State University of New York at Binghamton, Department of English, General Literature, and Rhetoric, 2005. / Includes bibliographical references.
62

Influência de variáveis de processo do desempenho de torre de resfriamento. / Influence of process variables on the cooling tower performance.

Mello, Lilian Cardoso de 29 August 2008 (has links)
Com base em um modelo fenomenológico e a partir de dados experimentais obtidos numa planta piloto, foi obtida uma correlação entre o desempenho de uma torre de resfriamento em função das principais variáveis de processo: fluxos mássicos do gás e da água pela torre, e temperatura de entrada da água. Os resultados apresentaram boa consistência, comparados com os da literatura. A metodologia desenvolvida pode, com relativa facilidade, ser aplicada para torres de resfriamento industriais, pois se baseia em medidas de variáveis, factíveis em termos práticos. Efetuou-se também um estudo paralelo com base em modelagem e simulações matemáticas do comportamento de uma torre de resfriamento de água em condições severas, com temperatura da água de alimentação superior a 50°C. Constatou-se que o coeficiente de transporte de massa na torre de resfriamento aparentemente não é afetado. / Cooling towers are widely used in many industrial and utility plants and its thermal performance is of vital importance. In the present work, using a phenomenological model and by experiments carried on over a pilot installation, the mass transfer coefficient dependence of air and water flow rates and inlet cooling water temperature is determined. The approach proposed may be useful in addition for characterization of industrial cooling towers since it depends on temperature and flow rate measurement usually available in typical plants. A parallel study concerning high mass transfer rate theory is accomplished. Through mathematical modeling and simulations based on this study no influence is detected on the mass transfer coefficient in the cooling tower, operating under harsh conditions with inlet water temperature up to 90°C.
63

Remote Tower Centre - Configuration and Planning of the Remote Tower Modules

Axelsson, Peter, Petersson, Jonas January 2013 (has links)
Today, many small aerodromes have a hard time surviving economically, and amongst the largest cost is air traffic control. Airlines are cutting costs where they can, and many times this affects the aerodromes as well, e.g. when airlines decide to park remotely instead of at the gate. The project called Remotely Operated Towers, initiated by SESAR and run by Saab and LFV, is aiming to address this problem. The project revolves around remotely providing ATS to aerodromes where it is deemed suitable. A big challenge in this project is how to assign aerodromes to remote tower modules in the remote control centre. There are many ways to do this, but there is only a few ways to do it to achieve the least amount of modules. This thesis aims to find an optimal solution to the challenge mentioned above. The thesis resulted in a model where the user can provide the input of choice, i.e. aerodromes with associated ATS operating hours and movements, for a specific period – and receive the assignment schedule for the modules, saying exactly which aerodrome are to be controlled by which module at what time.
64

Influência de variáveis de processo do desempenho de torre de resfriamento. / Influence of process variables on the cooling tower performance.

Lilian Cardoso de Mello 29 August 2008 (has links)
Com base em um modelo fenomenológico e a partir de dados experimentais obtidos numa planta piloto, foi obtida uma correlação entre o desempenho de uma torre de resfriamento em função das principais variáveis de processo: fluxos mássicos do gás e da água pela torre, e temperatura de entrada da água. Os resultados apresentaram boa consistência, comparados com os da literatura. A metodologia desenvolvida pode, com relativa facilidade, ser aplicada para torres de resfriamento industriais, pois se baseia em medidas de variáveis, factíveis em termos práticos. Efetuou-se também um estudo paralelo com base em modelagem e simulações matemáticas do comportamento de uma torre de resfriamento de água em condições severas, com temperatura da água de alimentação superior a 50°C. Constatou-se que o coeficiente de transporte de massa na torre de resfriamento aparentemente não é afetado. / Cooling towers are widely used in many industrial and utility plants and its thermal performance is of vital importance. In the present work, using a phenomenological model and by experiments carried on over a pilot installation, the mass transfer coefficient dependence of air and water flow rates and inlet cooling water temperature is determined. The approach proposed may be useful in addition for characterization of industrial cooling towers since it depends on temperature and flow rate measurement usually available in typical plants. A parallel study concerning high mass transfer rate theory is accomplished. Through mathematical modeling and simulations based on this study no influence is detected on the mass transfer coefficient in the cooling tower, operating under harsh conditions with inlet water temperature up to 90°C.
65

Air traffic controllers' work-pattern during air traffic control tower simulations : A eye-tracking study of air traffic controllers' eye-movements during arrivals

Svensson, Åsa January 2015 (has links)
The aviation industry evolves all the time in every possible sphere with new the technology that is advancing and the increasing amount of traffic on the airports. The air traffic control services has come a long way with automated systems and more advanced technology and the work of the air traffic controller (ATCO) has become more efficient to meet the higher demands for more traffic. But along with highly automated systems and work efficiency there can be a lack of safety instead if there is too much to do for the controller. A new concept in the aviation industry is developing; multiple remote towers, which means that one ATCO can be several miles away from the airports and handle two or more airports at the same time from the same work station. The air traffic controllers has to monitor the aircrafts, direct the traffic, make decisions and make sure that the pilots follows the instructions. At the same time the ATCO need to monitor the systems as well, making sure that everything is working as it is supposed to. To be able to maintain a safe environment for the controllers and the aircrafts, on and surrounding the runways, the controllers need to have situation awareness and the system they are working within need to be resilient to be able to cope with the different kind of situations that might occur. This study has focused on the role of the ATCO in air traffic control towers and by eye-tracking mapped what the controllers are looking at while handling arrivals in two different air traffic control towers. An episode analysis was made on several episodes that took place during different kinds of conditions in the two different air traffic control tower simulators, one single tower simulator and one multiple remote tower simulator. Patterns in the controllers’ way of handling arrivals were identified and the results from the controllers’ eye-movements shows that the ATCOs have a habitual behaviour pattern and that for almost every arrival they will act in the same way. The ATCO in the single tower simulator used the air radar several times during the episodes while in the multiple remote tower simulator the ATCOs almost never looked at the air radar. The radio was used more by the controllers in the multiple remote tower than in the single tower and it is discussed if this is something that can take too much time from an ATCO in a multiple remote tower. The results also highlights the importance of the strip-table, a tool used by the controllers during every step of the arrival process. The conclusions are that the system (controllers and non-human agents) has situation awareness and that the air traffic controllers have a clear frame of the situation. The results from this study can be seen as a guideline and a start for further research in this field and for the development of multiple remote towers. Further research should investigate in the controllers’ ability of reframing in situations of runway incursions and other unexpected events and the usage of the radio in multiple remote towers.
66

CAE modelling of cast aluminium in automotive structures

Singh, Subrat, Veditherakal Shreedhara, Sreehari January 2019 (has links)
In the automobile industry, there is a big push for the automotive car manufacturers to base engineering decisions on the results of Computer Aided Engineering (CAE) solutions, and to transform the prototyping and testing, from a costly iterative process to a final verification and validation step. The variability in components material properties and environmental conditions together with the lack of knowledge about the underlying physics of complex systems often make it impractical to make reliable predictions based on only deterministic CAE models. One such area is the CAE modelling of cast aluminium components. These cast aluminium components have gained a huge relevance in the automobile industries due to their commendable mechanical properties. The advantage of the cast aluminium alloys are being a well-established alloy system in manufacturing processes, their functional integrity and relatively low weight. However, the presence of pores and micro-voids obtained during the manufacturing process constitutes a specific material behaviour and establishes a challenge in modelling of the cast materials. Furthermore, the low ductility of the materialdemands for the advanced numerical model to predict the failure. The main focus of this master thesis work is to investigate modelling technique of a cast aluminium alloy component, a spring tower, for a drop tower test and validate the predicted behaviour with the physical test results. Volvo Car Corporation currently uses a material model provided by MATFEM for cast aluminium parts which are explored in this thesis work, to validate the material model for component level testing. The methodology used to achieve this objective was to develop a boundary condition to perform component level tests in the drop tower and to correlate these with the obtained results found by using various modelling techniques in the explicit solver LS-DYNA. Therefore, precise and realistic modelling of the drop tower is crucial because the simulation results can be influenced by major design changes. A detailed finite element model for the spring tower has been developed from the observations made during the physical testing. The refined model showed good agreement with the existing model for the spring tower and observations from physical tests.
67

Improving UK greenhouse gas emission estimates using tall tower observations

Howie, James Edward January 2014 (has links)
Greenhouse gases in the Earth’s atmosphere play an important role in regulating surface temperatures. The UK is signatory to international agreements that legally commit the UK to reduce its greenhouse gas emissions, and there is a scientific and political need to better understand greenhouse gas sources on regional scales. The current methods used to provide greenhouse gas emission inventories rely on ‘bottom-up’ techniques and have large associated errors. However, it is also possible to use observations of atmospheric concentrations of greenhouse gases and models of atmospheric transport to link the observations with source regions in order to estimate emissions in a ‘top-down’ approach. The key findings presented in this thesis are (a) UK emissions can be retrieved from the Angus tall tower in Scotland using the NAME inversion technique at a finer spatial resolution than has previously been reported using similar ‘top-down’ inverse methods; (b) atmospheric measurements from the Angus tall tower in Scotland have been used for the first time with the NAME inversion technique in order to estimate UK emissions of methane, nitrous oxide and sulfur hexafluoride for the years 2006 to 2009; (c) increasing the number of towers in UK network substantially increases the spatial resolution of greenhouse gas emission estimates. The errors and uncertainties associated with the NAME inversion over the UK domain are discussed and potential future improvements to this approach are presented. Overall, the work presented in this thesis has contributed to our understanding of the spatial and inter-annual variability of UK greenhouse gas emissions.
68

Tall concrete buildings subject to vertically moving fires : a case study approach

Fletcher, Ian A. January 2009 (has links)
Fire in buildings can have a severe impact in terms of both human safety and potential economic loss. This is especially true in the case of fires of such severity that the building structure is damaged. Concrete buildings are traditionally regarded as safe in a fire situation as concrete is non-flammable and exhibits highly insulating material properties. The majority of current research relating to the impact of fire on structures examines other forms of construction. Research of concrete in fire is generally limited to investigation and testing of individual members in order to understand the often complex interactions exhibited by concrete as a material at high temperatures. This research seeks to redress the balance by using a systematic approach to examine effects of fire on a holistic concrete structure in simplified but realistic temperature exposures. The research utilises evidence and structural information from the Windsor Tower in Madrid, which suffered a major fire in February 2005 with partial collapse in some areas of the structure. The fire spread throughout the building, travelling both upwards and downwards. Computer modelling was used extensively. Computational Fluid Dynamics (CFD) analysis was used to explore likely fire temperature and duration in localised areas. Structural Finite Element Modelling (FEM) was used to develop a hierarchy of models, beginning with simple structural forms and progressing logically to more detailed structures. This produced a systematic and comprehensive analysis of the reaction of the structure to fire for comparison to the real, observable damage to the building and assessment of generic failure behaviours. The structural model produced was used with a number of variations in support condition, fire spread rate and extent, and fire protection. It was found that for a structure of this type, structural stiffness of the concrete floors was insufficient to compensate for the loss of strength in heated steel members where there was no alternative load redistribution path. It was also found that in the case where an alternative load path exists, but involves steel members which have previously heated during the multiple-floor spread of the fire, the rate of fire spread has a critical effect on the structural stability.
69

Pulling Tangled Strings: "The Puppeteer" and Other Stories

Berryman, Archer 08 1900 (has links)
Pulling Tangled Strings: "The Puppeteer" and Other Stories is a collection of stories with strong thematic and emotional connections that includes an opening preface describing the process used when writing the stories. Each of the stories is united by a main character that desperately wants to gain control of his environment. From a character acting out a classic revenge tale on his friend to a comatose teenager victimized by an ambiguous tragedy, these are characters who have been put into difficult life situations and need to feel like they are pulling the strings in their lives again. In all cases, however, the characters come to find that control does not come easily and that the motivations for their behavior are never clear cut, even to themselves.
70

A geography of the new public health

Coombes, Yolande Jane January 1993 (has links)
Using the example of a locality this thesis examines the key elements of the new public health from a geographic perspective. Three voluntary groups (based in the London Borough of Tower Hamlets) have been examined as a case study of expressions of the new public health. The thesis argues that the new public health is an urban social movement, which has expressions at the local level which vary. It is argued that this variance results from the key elements which inform and shape the new public health. They are the nature of the public health activities and initiatives carried out; the organisation and representation of the groups that make up the movement; and the knowledge and activities informed by sense of the place that the groups have. The sense of place of the groups collectively, and the individuals within the groups, informs what public health activities and initiatives are implemented based on perceived need. The sense of place of the area is also the main mobilising factor for the agents who make up the public health groups and hence the new public health movement. The new public health movement is an urban social movement organised at a number of different geographical levels and in particular at the local and international levels. In discussing and describing how the new public health is a social movement, the thesis contends that previous exploration of social movements has failed to examine the importance that place has to the organisation and shape that movements take. This thesis, through a geographic analysis, constructs a new framework for looking at urban social movements with an emphasis on place. It also outlines how an geographical analysis of the new public health can broaden the focus of current research within medical geography by examining health within the wider context of society.

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