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To improve aircraft structural performance requires practical design changes and better incorporation of advanced technologies. Instability failure modes typically constrain aerospace panel designs because buckling occurs at stresses less than that of material yield. Buckling containment features, small stiffeners located between the primary stiffeners/stringers, provide the ability to significantly improve panel-buckling stresses and thus exploit the full potential of available materials. Inclusion of buckling containment features into industrial panel sizing procedures is constrained by the current inability to robustly predict and understand the complex buckling behaviour. To aid inclusion requires a novel design approach that facilitates the extraction of understanding and selection of the optimum design. The project develops a finite element modelling methodology that permits robust buckling behaviour prediction of plates with buckling containment features. A novel design chart presents compression and shear loading buckling behaviour predictions that are applicable to both high load intensity wing and low load intensity fuselage applications. Interrogation of the design charts enhances current understanding of how plates with buckling containment features buckle. An experimental verification indicates the finite element modelling methodology to be accurate to within approximately 20% and 7% for initial and collapse buckling behaviour respectively. These deviations result from differences between the configuration of the finite element modelling methodology, the design of the test specimens, and the experimental setup. The work develops the first theoretical compression buckling framework for predicting PBCF buckling behaviour subject to compression loading. A verification process against predictions finite element analysis indicates a correlation error of less than 5% when considering structure of aspect ratio greater than three. Furthermore, using regression analysis and finite element analysis, the work develops a computationally efficient closed-form means to predict PBCF buckling behaviour that is suitable for inclusion into early (conceptual/preliminary) aerospace panel sizing procedures.

Electric propulsion provides many benefits when compared to fully-mechanical power transfer. These benefits include increased configurability, efficiency, ease of control and an ability to offer redundancy. The improved fuel-consumption offered by hybrid electric-mechanical propulsion systems is particularly important to the transport sector. Recent governmental and climate-change targets, which have been driven by the depletion of fossil-fuel reserves, place a growing focus on these propulsion and actuation technologies. The demand to electrify existing commercial products burdens manufacturers to develop and mature electrical systems such that they can be produced in high volumes at low-cost. This pressure places a strong emphasis on the adopted design procedure's suitability for a given application and system requirements. A series-hybrid transmission system for a skid-steered vehicle forms the basis of presented work. The thesis design focus is a high-speed, fault-tolerant electrical machine and is purposed to actuate a "steering input" on this bespoke transmission. The electrical machine design requirements are unusual. The physical envelope is unconstrained and the transmission will be designed to accommodate the prototype; however, a compact machine with minimised mass is desirable. A design methodology for modular-wound electrical machines is developed and presented. The method draws upon published work in electro-magnetic and thermal optimisation; however it is specifically tailored to handle a design problem with an unspecified physical envelope. It is shown that a template electro-magnetic design may be generated to produce an optimal initial geometry; this template is subject to a thermal scaling study which ensures the output requirements are satisfied. Sub-assembly testing provides a useful approach for obtaining difficult to model thermal parameters and calibrating 'stray' AC loss effects. The presented methodology requires fewer design iterations when compared to common procedures; furthermore, it reduces the overall design and prototyping costs without incurring a disproportionate increase in computation-time. The research culminates in a prototype 12000 rpm, 40 kW, 12-slot, 10-pole, interior permanent magnet electrical machine. Electrical fault-tolerance is demonstrated utilising a segmented, 3-phase "machine-modular" stator design, comprising of single-layer concentrated windings. The machine stator is constructed with inexpensive solid conductors. With careful consideration of winding conductor placement, reduced AC losses are exhibited which yields a prototype with a competitive power-density. The dominating factor which governs a machine's achievable specific-output is shown to be the stator's thermal characteristics. These characteristics are not only a function of the materials and construction techniques used, but are equally impacted by stator split-ratio and the choice of physical envelope. The presented design method allows these envelope dimensions to be identified and generates an initial design which is close to the global optimum.

This thesis offers a new interpretation of the life and importance of George Padmore (1903-1959). Padmore was one of the most well-known ‘black communists’ in the 1930s. He became a major nexus for anti-colonial resistance in London between 1935- 1957 and one of the foremost political thinkers behind the pan-African movement. Through an analysis of his writing and his networks this thesis argues that Padmore engaged in a permanent state of political activity, guided by a practice of ‘pragmatic anti-imperialism.’ By tracing his journalism in West African and West Indian colonies, it shows that Padmore’s influence was far more extensive than previously imagined. This study begins from the hypothesis that the pragmatism of Padmore’s politics can only be demonstrated by examining his whole life, and thus takes the form of a biography. Taking Padmore’s pragmatism as a starting point, the forms in which he was understood and labeled by others are fundamental to this study since they demonstrate the extent to which Padmore was willing to compromise and ‘play the game’ of imperial politics, and they show the boundaries of the field in which he operated. Overall, this thesis aims to contribute to a deeper understanding of race and non-violent resistance in anti-imperial politics in the first half of the twentieth century by focusing upon the role of a mobile, life-long activist from the diaspora who attacked the moral basis of late colonial rule from within.

The broad aim of this research was to develop a methodological approach to the monitoring of archaeological sites that contained, or had the potential to contain, well-preserved organic archaeological remains, by means of a multidisciplinary approach. Such sites could generally be referred to as wetland archaeological sites, as material is preserved as a function of an existing or former wetland environment. Such an approach would provide high quality data from different sources that could be considered mutually supportive, generating information that could therefore be considered reliable. The more specific aims of the research can be considered as: 1. To develop a monitoring package that can effectively and accurately identify conditions that are conducive to the long-term preservation of organic archaeological materials, specifically wood. 2. To understand in detail the burial dynamics of Sutton Common. 3. To identify the changes within the burial environment on Sutton Common that occurred as a direct consequence of activities aimed at raising the watertable and to assess whether these aided the potential for in situ preservation. Of significance is the amount and quality of the data collected, with the techniques used generating high resolution data over an extended period of time. Such data concerning the burial environment has not previously been collated to such an extent. To satisfy these three specific aims, a monitoring approach was chosen that made use of multiple factors; these being hydrological monitoring, soil redox monitoring and microbiological assessment. The most crucial of these, and the one that has been the focus of the monitoring effort, has been the hydrological monitoring as this is essential at identifying saturated conditions, which are the basic conditions required for good preservation. Soil redox monitoring closely supported this by being capable of identifying anaerobic conditions that indicate stable conditions, ideal for preservation. As soil redox monitoring requires more resources in terms of time and funds, this variable has not been as widely implemented as the piezometer grid installed for hydrological monitoring. Such factors have also influenced the implementation of microbial techniques on Sutton Common, with these being applied as an assessment, and a means of gathering baseline data, rather than a monitoring variable proper. The presentation of these techniques and the specific methods used have been detailed in Chapter 3, with the results of the monitoring programme for each of the approaches being presented in Chapters 5, 6 and 7 in the context of previous monitoring exercises and published literature. The significant findings were discussed and specific reference made to the impact of flooding on Sutton Common and the influence of re-wetting activities in Chapter 8. The concluding chapter summarises the main findings of each of the three disciplines studied along with the findings obtained from the analysis of the flooding event of 2000/01, and the effects of the drainage mitigation implemented on Sutton Common. These are then related to the original aims set out in Chapter 1, followed by the wider implications of this research and the main recommendations arising from it.

This thesis examines visual representations of English country life and labour in the period 1870 to 1905 in relation to contemporary beliets in the centrality of the rural world to conceptions of national identity and'Englishness'. Centering upon an analysis of oil and watercolour paintings, but also interrogating prints, posters and photographs, the thesis examines the ways in which the production and consumption of images of rural lite in the period addressed and articulated widespread elite cultural concerns over a complex range of social issues, including purported racial degeneration, growing class conflict, and the checking of British imperial ambitions. Divided thematically into five distinct yet interlinked chapters, the thesis investigates firstly the stylistic evolutions in the painting of rural life across the period, and the connections made between particular visual languages and notions of a'national' school of art. The second chapter focuses upon an assessment of pictorial representations of the farmworker, looking in particular at the ways in which visual descriptions of rural labourer's bodies explored ideas of racial identity and national character. Chapters Three and Four look in turn at the representation of the country village and of field sports, the chapters both individually and cumulatively charting the relationship between visual culture and the generation of ideas around community,d eferencea nd social cohesion. The final section addressesth e portrayal of agricultural work, looking specifically at the themes of ploughing and mechanisationa, nd the cultural negotiationo f signso f modernity in the countryside. Treating visual images not as historically-transcendant objects, but as significant elements within a particular and specific material culture, the thesis compares visual images to other contemporary accounts of rural life, including those offered in novels, poetry and agricultural journalism. It views paintings of rural life and labour as critical spaces in which contemporary elite ideologies were actively articulated and contested, describing paintings of the rural world not as sites of settled meaning, but rather as formative elements of a dynamic process that continually re-worked and reevaluated evolving conceptions of rurality and'Englishness'.

'Science invites her admirers here, presenting one a knot of questions to solve respecting these rifted rocks, and those huge fragments of stone, that lie arranged in such orderly array ...' These words written of the Malham area in 1847 by A. McFarlane seem particularly appropriate to commence a work which attempts to look at a few of the questions regarding 'those rifted rocks'. The study of karst processes is yet in its youthful stages and it is hoped that the research presented in this thesis will advance to some degree knowledge of that part of England which 'presents us with creation in its boldest outlines' (McFarlane, 1847), in addition to furthering an understanding of the wider problems of the evolution of limestone terrains. In contrast to much speculative and theoretical reasoning that typifies some recent writings in limestone studies this work is based primarily, on systematic observations carried out on karst waters in the natural environment. There were six interrelated reasons for collecting this information: (i) To investigate in detail the role of antecedent hydro-meteorological factors, particularly effective precipitation and air temperatures,in initiating; (a) temporal variations in solutional losses at the sampling sites, (b) variations in the temperature of water recorded at these sites, and (c) the pattern of discharge fluctuations recorded at the selectedsites. (ii) In view of the recent separation of karst water into 'allogenic karst water' and 'karst spring water', or into percolation-fed springs and systems of the sink-resurgence type, it was considered important to discover how contrasts in the mode of recharge to the limestone could affect the recorded pattern of solute concentrations at the risings and the pattern of water-temperature variation recorded at the risings. (iii) Thirdly in view of the fact that recent work has pointed to the role of both lithological factors (Sweeting and Sweettng, 1969) and hydrological influences (Pitty, 1968,1971) in affecting mean solute concentrations in karst waters, regional variations in the mean solute concentrations and in the variability of solute concentrations are examined. (iv) Fourthly to discover those factors instrumental in causing regional variations in the mean temperature of water discharging at karst risings in the field area, and in causing regional variations in the level of fluctuation of water temperature at karst risings. (v) To investigate seasonal and regional differences in the time taken for circulating water to pass through the limestone systems (flowthrough times). (vi) Lastly to accumulate evidence concerning the nature of water disposition and ground-water flow in the limestones of the field area. This research was carried out in the Fountains Fell and High Mark upland areas of the central Pennines. These two areas provide a contrasting geological framework for this work, one area (Fountains Fell) being of limestone partially covered by Yoredale and Millstone Grit series, and the other (High Mark) consisting almost completely of Great Scar Limestone. Geological differences have given rise to the hydrological contrasts between the two areas with which some of this research is concerned. In addition this is an area of the Pennines in which comparatively little work has previously been carried out, earlier interests having been mainly centred on the Ingleborough area to the west, the locality of Malham and Malham Tarn, or in the southern Pennines. On account of the fundamental significance of geological, hydrological, biological and climatic factors to the operation of karst processes, a full description of these aspects of the field area is included in this work.

1. Physiological experiments were devised to study the electrical responses of ochinoderm muscle during contraction. The smooth muscle forming the lantern retractors of Eching conducts spike potentials at a speed off 4 cms. A sec. 2. Three muscle systems examined with the electron microscope reveal a layout that varies in complexity. The muscle cells give rise to processes that are synapsed upon by nerves. 3. The area containing the ribbon axons described by Smith (1950) was examined and the ribbon axons shown to be selectively stained muscle cells. 4. In the three muscle systems examined controlling ganglion was found to be associated sytams. 5. The ganglia contained large numbers of structures that are described as synapses. These synapses are of a simple type and do not possess the specialisations that are present in the synapses of some other invertebrate phyla. 6. The sensory cells of the epithalium are described and an examination has indicated that the cells of the general epithelial are all sensory and contribute axons to the nerve plexus. Some of these epithalial cells are modified into probable chemoreceptors, light receptors and are found in statocysts. 7. A hypothesis to account for the co-ordination of the behaviour of echinoderms in propounded.