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Distributing and sharing entanglement at a distance is a key ingredient in many future quantum communication protocols, however entanglement is a fragile resource and can break down upon interacting with the environment. Within this thesis we present two possible entanglement swapping protocols, and show that these protocols are resilient to small levels of photonic losses. We propose the use of these protocols in quantum communication schemes that require shared entangled qubits, in the form of a Bell state. The input states to our proposed protocols are hybrid entangled states, which are discrete-variable and continuous-variable entangled states. We use the vacuum and single photon Fock state as our discrete half, which is stationary in our entanglement swapping protocol, whereas the continuous variable half is modelled as travelling through lossy optical fibre before being measured. The first protocol uses coherent states in a superposition as propagating modes in our entanglement swapping setup, whereas the second, more complicated, protocol uses superposed cat states. We model photonic losses by applying a beam-splitter of transmission T to our propagating continuous variable modes, along with an input vacuum state. We also model the more realistic circumstance in which the losses in these two continuous variable modes are not equal. We then detect these continuous variable modes using a vacuum projective measurement and balanced homodyne detection. We also investigate homodyne measurement imperfections and non-ideal outcomes, as well as success probabilities of these measurement schemes. We calculate the entanglement negativity and linear entropy of our final two qubit state, as well as fidelity against the |\Phi^+ > Bell state in the coherent state protocol, and a phase-rotated |\Phi^+(\alpha)> Bell state in the cat state regime. We demonstrate that a small amount of loss mismatch does not destroy the overall entanglement, thus demonstrating the physical practicality of this protocol.

A thorough experimental and theoretical characterization of the effect of electrostatics on the electrospray process, focusing particularly on the flow rate sensitivity to the applied potential difference (voltage), has been completed. The flow rate and current increase linearly with the applied voltage within cone-jet mode. The effect of geometry on the flow rate to voltage relationship is sensitive to two parameters – the hydraulic resistance and the variation of the electric pressure sensitivity to external geometry. A theoretical and FEM model based on the calculation of the electric field provides an explanation of the geometry variation. This allows for an estimation of the change of flow rate with voltage, under any geometrical circumstance. For the first time the effect of voltage on flow rate across enhanced dripping, pulsed and multi-jet electrospray regimes are outlined. With the exception of enhanced dripping, a linear increase is noticed within most regimes, and is geometrically sensitive. Also at the onset of cone-jet mode a drop in flow rate occurred. The variation of flow rate with voltage can be applied to colloid thrusters to vary the performance. Using the theory outlined in this thesis, an estimate of the flow rate change for a colloid thruster is described, along with its associated performance variation. The effect of voltage on current in cone-jet mode electrospray is detailed, with a similar geometric dependence as the flow rate to voltage relationship established. It is also sensitive to various other parameters, including nominal flow rate. The stability island of cone-jet mode electrospray is explored, and its relationship to the variation of electric field with voltage is outlined. The effect of emitter and electrode geometry on cone-jet onset voltage and cone-jet voltage range is outlined.

Despite the large media coverage around Iran’s military actions, the role of the Artesh in Iran’s national security structure is often unmentioned. Looking at the evolution of the Artesh since the fall of the Shah of Iran, this study uses firsthand accounts, recent research, and governmental statements and reports to trace the Artesh’s journey to present day. It examines several battlefield successes and failures during the Iran-Iraq War to gauge the ability of the Artesh to adjust in a wartime environment. These adjustments are mixed with some valuable lessons being implemented to later battles while other important lessons remained unapplied. It employs victory theory to the Artesh Navy’s 2007 naval reforms, evaluating the congruence of the reforms with Iran’s vision of naval warfare, and concludes that Iran’s reforms are inline with its strategic goals at sea. The results of this study help shed light on the applications of the Artesh and Iran’s abilities to exercise power using it outside the original post-Iran Iraq War intent and may support further study of this significant topic.

Visual sensing in robotics, especially in the context of autonomous vehicles, has advanced quickly and many important contributions have been made in the areas of target classification. Typical to these studies is the use of the Red-Green-Blue (RGB) camera. Separately, in the field of remote sensing, the hyperspectral camera has been used to perform classification tasks on natural and man-made objects from typically aerial or satellite platforms. Hyperspectral data is characterized by a very fine spectral resolution, resulting in a significant increase in the ability to identify materials in the image. This hardware has not been studied in the context of autonomy as the sensors are large, expensive, and have non-trivial image capture times. This work presents three novel contributions: a Labeled Hyperspectral Image Dataset (LHID) of ground-level, outdoor objects based on typical scenes that a vehicle or pedestrian may encounter, an open-source hyperspectral interface software package (HSImage), and a feature selection based sensor design algorithm for object detection sensors (DLSD). These three contributions are novel and useful in the fields of hyperspectral data analysis, visual sensor design, and hyperspectral machine learning. The hyperspectral dataset and hyperspectral interface software were used in the design and testing of the sensor design algorithm. The LHID is shown to be useful for machine learning tasks through experimentation and provides a unique data source for hyperspectral machine learning. HSImage is shown to be useful for manipulating, labeling and interacting with hyperspectral data, and allows wavelength and classification based data retrieval, storage of labeling information and ambient light data. DLSD is shown to be useful for creating wavelength bands for a sensor design that increase the accuracy of classifiers trained on data from the LHID. DLSD shows accuracy near that of the full spectrum hyperspectral data, with a reduction in features on the order of 100 times. It compared favorably to other state-of-the-art wavelength feature selection techniques and exceeded the accuracy of an RGB sensor by 10%.

This thesis documents the design and testing of a sub-newton High Test Peroxide (HTP) monopropellant thruster architecture, suitable for micro and nanosatellite applications. The main goals were to demonstrate that a thruster targeting a 0.1 N thrust level could achieve a high performance, and to investigate the fundamental processes governing its operation. The thruster design exhibited high thermal performance using 87.5 %wt. HTP, with chamber temperatures in excess of 600 °C, corresponding to characteristic velocity efficiencies approaching 0.963 ± 0.004 (1휎). These values are similar to equivalent larger-thrust systems. The thruster was also tested with 98.0 %wt. HTP, with temperatures approaching 800 °C. These results represent some of the highest performance of an HTP monopropellant system, and is a first at sub-newton thrust levels. The experimental results were collected by direct measurement of the internal fluid conditions, something not previously achieved on a thruster of this scale. This was made possible by the novel application of conventional metal additive manufacturing techniques, permitting the inclusion of integrated instrumentation standpipes and other complex ancillary geometry. The manufacturing process also enabled the production of a large number of different catalyst bed designs for use in one of the most extensive experimental studies on the impact of the catalyst bed geometry. The geometry was parametrically defined by the catalyst bed loading and aspect ratio, with respective values ranging from 1.48 kg.m⁻².s⁻¹ to 64.8 kg.m⁻².s⁻¹ and 0.33 to 6. The baseline thruster design, with a nominal bed loading of 10 kg.m⁻². s⁻¹ and an aspect ratio of 2, had the highest demonstrated performance. However, data analysis suggested that lower catalyst bed loadings and aspect ratios, i.e. shorter and wider beds, should be more optimal over a blowdown range. The study provided data towards validating a simplified pseudo-physical front model of the catalyst bed. This model describes the phase transition between the cool liquid/multiphase and the hot gas regimes. The phase change front was found to be axially close to the complete decomposition front, representing the maximum temperature in the bed. The catalyst bed flooding condition was used to relate the fundamental reactivity of the catalyst bed to the pseudo-physical front model. It was proposed that the reactivity can be used to size a bed with minimal experimental testing, through the Damköhler number: the estimated liquid-phase decomposition rate was greater than the rate of forced propellant diffusion for nominal catalyst bed operation. The pressure roughness phenomenon was also investigated using spectral analysis. These results were used to justify the proposed local oscillatory diffusion process in the catalyst bed. This is responsible for the pressure roughness, as well as the localised choking in the upstream liquid/multiphase regime that causes high pressure drop over this region. An extensive study on microinjectors was also conducted. This is a field of limited published research. The study characterised the performance of Poiseuille-type microbore tube and Venturitype orifice plate injectors. Poiseuille injectors demonstrated stable performance while orifice injectors were challenging to manufacture and prone to blocking. 'Chugging' flow instabilities were also captured, and it is proposed that the onset of this condition is tied to the inertia of the propellant flow through the injector. This, along with the minimum critical flow rate for the Venturi cavitation phenomenon, suggests that the Poiseuille microinjectors are a more robust architecture and better suited to sub-newton monopropellant thrusters.

Automatic language identification has been applied to short texts such as queries in information retrieval, but it has not yet been applied to metadata records. Applying this technology to metadata records, particularly their title elements, would enable creators of metadata records to obtain a value for the language element, which is often left blank due to a lack of linguistic expertise. It would also enable the addition of the language value to existing metadata records that currently lack a language value. Titles lend themselves to the problem of language identification mainly due to their shortness, a factor which increases the difficulty of accurately identifying a language. This study implemented four proven approaches to language identification as well as one open-source approach on a collection of multilingual titles of books and movies. Of the five approaches considered, a reduced N-gram frequency profile and distance measure approach outperformed all others, accurately identifying over 83% of all titles in the collection. Future plans are to offer this technology to curators of digital collections for use.

This thesis investigates high-performance electrospray thrusters for nanosatellite applications. The thruster, termed Porous-emitter Electrospray Thruster (PET), consists of a porous emitter and a porous propellant reservoir made, allowing propellant to be transported passively. In order to increase the electrospray emission density and thrust density, different PET thruster emitters manufactured using low-cost techniques were studied using numerical simulations and by experiments. The electric field simulations suggest that the onset voltage of a porous emitter, contrary to capillary emitters, decreases with the size of the Taylor cone on the emitter tip. Based on multiple thruster tests in a vacuum, the onset voltages were between ±1800 to ±2200 V. The PET electrospray thrusters demonstrated high emission current, with the maximum values around 3 mA near ±3500 V. The per-tip emission current up to around 100 µN was high compared to most state-of-art development and was found mainly a result of the large emission tips that introduce more emission sites. Time-of-flight characterisations suggest that the emitted particles were mainly monomer ions and dimer ions with high specific impulse ranging from 3891 to 7459 s. The estimated thrust ranges from approximately 0.8 to higher than 263.5 µN, higher than most similar designs. The polydispersive efficiency due to the presence of multiple particles was calculated, ranging from 86.1% to 94.5%. The voltage losses of the thruster were measured using a retarding potential analyser, suggesting a non-kinetic efficiency from 92% at -2100 V to 86.7% at 2600 V. Evidence of the fragmentation from dimer ions to monomer ions was found in retarding potential analysis results, and their energy variations agree with theoretical calculations. The thruster plume angle increased from 12.4 degrees at low voltages of ±1800 V to approximately 60.8 degrees at high voltages of ±3500 V, with the angular efficiency decreased from 99.2% to 88.8%, correspondingly. The trajectory of charged particles in the plume is studied using numerical simulations, and the results suggest that the increase of the plume area is mostly a result of the expanded emission area at high voltages. By estimation, the thruster power efficiency ranges from 50% to 60%. The PET thrusters demonstrated a relatively high emission current and thrust at the cost of higher operating voltages and power. A PET thruster was tested continuously for 18 hours with relatively stable emission current and minor variations. The thruster performance was evaluated in two nanosatellite mission scenarios requiring high velocity-changes and precise thrust, and they show adequate manoeuvre performance. The preliminary studies in this thesis demonstrated that the PET electrospray thrusters have promising propulsive performance, and further development is recommended.

The problem of roadway navigation and obstacle avoidance for unmanned ground vehicles has typically needed very expensive sensing to operate properly. To reduce the cost of sensing, it is proposed that an algorithm be developed that uses a single visual camera to image the roadway, determine where the lane of travel is in the image, and segment that lane. The algorithm would need to be as accurate as current lane finding algorithms as well as faster than a standard k- means segmentation across the entire image. This algorithm, named IRIS, was developed and tested on several sets of roadway images. The algorithm was tested for its accuracy and speed, and was found to be better than 86% accurate across all data sets for an optimal choice of algorithm parameters. IRIS was also found to be faster than a k-means segmentation across the entire image. IRIS was found to be adequate for fulfilling the design goals for the algorithm. IRIS is a feasible system for lane identification and segmentation, but it is not currently a viable system. More work to increase the speed of the algorithm and the accuracy of lane detection and to extend the inherent lane model to more complex road types is needed. IRIS represents a significant step forward in the single camera roadway perception field.

RSS-based localization is a promising solution for estimating the position of a non-collaborative emitter using a network of collaborative sensors. This paper examines RSS-based localization and differential RSS (DRSS) localization in the presence of correlated shadowing with no knowledge of the emitter's reference power.  A new non-linear least squares (NLS) DRSS location estimator that uses correlated shadowing information to improve performance is introduced. The existing maximum likelihood (ML) estimator and Cram\' er Rao lower bound (CRLB) for RSS-based localization given do not account for correlated shadowing. This paper presents a new ML estimator and CRLB for RSS-based localization that account for spatially correlated shadowing and imperfect knowledge of the emitter's reference power. The performance of the ML estimator is compared to the CRLB under different simulation conditions. The ML estimator is shown to be biased when the number of sensors is small or the shadowing variance is large. The effects of correlated shadowing on an RSS-based location estimator are thoroughly examined. It is proven that an increase in correlated shadowing will improve the accuracy of an RSS-based location estimator. It is also demonstrated that the ideal sensor geometry which minimizes the average error becomes more compact as correlation is increased. A geometric dilution of precision (GDOP) formulation is derived that provides a metric for the effect of the position of the sensors and emitter on the location estimator performance. A measurement campaign is conducted that characterizes the path loss at 3.4 GHz. The measurements are compared to the log-distance model. The errors between the model and the measurements, which should theoretically be Gaussian, have a Kurtosis value of 1.31. The errors were determined to be spatially correlated with an average correlation coefficient of 0.5 at a distance of 160 meters. The performance of the location estimators in simulation is compared to the performance using measurements from the measurement campaign. The performance is very similar, with the largest difference between the simulated and actual results in the ML estimator. In both cases, the new NLS DRSS estimator outperformed the other estimators and achieved the CRLB.

LAMBDA was an exploration of science and art in two components: a performance-lecture and an art installation. This project asserted that performance and art are effective methods of delivering scientific information to a general audience. The first component was a solo performance-lecture that used lights, projection, costumes, props, and sound in a hybrid classroom space. The performance-lecture covered the topics of light, the Aurora Borealis, gravitational lensing, and the cosmic microwave background. The art installation used light emitting objects to visually represent the gravitational disturbances that exist within a section of space-time.

Approximately 4% of all fatal crashes in the United States (1,092) occurred in cross path collisions at signalized intersections (NHTSA, 2011). This type of crash is especially dangerous as the victim driver is often oblivious to the impending collision. With the invention of a new traffic monitoring system WICAS (King et al., 2007), a proposed system to warn victim drivers of these crashes was studied. Novel out-of-car signals were designed using best practices in traffic signal design for reaction time and using some form of a familiar traffic sign/signal currently in use. A survey was conducted to determine the signals' validity of use in a simulation study. The survey found that drivers were inclined to stop at the signals even when their implied meaning was not conveyed. Once the signals were approved, a simulation was performed using the STISIM driving simulator to test driver reaction time based on signal type and light onset distance. Three signal types were used in the study: a regular progression signal, a novel "Do Not Enter" traffic signal, and a novel Growing traffic signal at onset distances of 250 and 300 feet. A repeated-measures two-way ANOVA found a significant difference in reaction times based on the interaction between signal and light onset distance. Both novel signals provided faster reaction times to the warning regardless of the onset distance. Thus, the use of either of the proposed novel signals would give the victim driver additional time to stop and assess the situation.

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The problem to be dealt with in this paper is the effect of social ridicule on the ego-strength of the individual. In being forced into the restricted social existence common with the alcohol addict, a significant decrease in ego-strength is to be expected.

The primary aim of this research is to develop my own critical perspective on oppression, marginalisation and education in Kerala, India. First, it critiques Freire’s educational thoughts including banking and problem-posing education; second, it goes on to extend Freire’s ideas to develop a dialogical methodology in the field of Education while addressing my fieldwork struggles and dialogues. Third, it addresses how Freire’s educational thoughts can also be critically understood to explore the oppressive and marginalizing nature of non-formal education and community work in Kerala; fourth, this thesis contributes to innovative knowledge mainly at theoretical, methodological and empirical levels.

This thesis considers the experience of a group of medical educators undertaking an MA Education programme. At its heart is the notion that actions and thinking are determined by unacknowledged ideas and assumptions and the premise that if these can be unearthed and understood they can be examined, considered, changed and developed. Most medical educators are medical practitioners who, in addition to their role as clinicians, have become educators. They are in a unique position to influence the practice of their colleagues and so affect the quality of medical care that patients receive. Currently medical education is underpinned by an unacknowledged technical-rational approach which mistakes the nature of professional practice and the nature of education. Medical education is being pursued as a branch of medical practice, rather than as a branch of education. The MA Education (medical educators) programme at the University of Winchester embodies a very different approach to the one prevailing in medical practice and education. It is an approach that is acknowledged and critiqued and which recognises the nature of professional practice and education. Using a methodology derived from educational research, the response of medical educators to the MA programme is investigated through data collected from eleven semi-structured interviews. The response of the interviewees to the programme is analysed and its consequences and implications explored. Although the programme’s approach is initially surprising and uncomfortable for medical educators they recognise their practice within it and develop professionally, primarily as educators but also as clinicians. The findings show that medical educators and medical education need to acknowledge and shed the prevalent technical-rational approach and embrace an approach which embodies an appreciation of the nature of professional practice and of education and of how practice is learnt. The MA programme experienced by the medical educators in this study is one example of how this can be achieved. The contribution of this thesis is to analyse one way in which medical educators can shed their technical-rational approach to professional practice and how and why they develop professionally through so doing. It emphasises the pivotal role of medical educators within medical practice and draws attention to the importance of the question of how practice is learnt.

This thesis is based on a study into the tensions and struggles between written government policy on inclusion and the reality of living and lived policy in Kenya, taking the experiences of a primary school’s attempt to become inclusive as its primary focus. The methodology builds on the metaphorical concepts of a ‘rhizome’, ‘tree’, ‘lines of flight’ and ‘becoming’ as they are espoused by Deleuze and Guattari (1987) in their philosophical writings in the book, A thousand plateaus. The contrast between the rhizome and the tree provides the basis for the critique of 'methodolatory' (Chamberlain, 2000: 287) and creates spaces for creative imagination in conducting inclusive research. The thesis advances a view of IE as a becoming, and draws upon the ‘philosophies of difference’ to offer new lenses for thinking and acting inclusively within schools (Allan, 2008). Through a rhizoanalytic approach, the relations and connections between written and lived policy are explored in order to consider what sort of educational spaces might be worthy of the inclusion of children and adults. The thesis also examines the wider contexts within which exclusive tendencies are harboured. Besides the surface view of inclusive education, participant accounts and conceptualisations imply that there is an invisible view of IE which is informed by a much more complex set of understandings. Therefore, teachers in their attempts to teach inclusively are often caught up in these complexities and disciplinary power networks which can be understood if they work closely with policy officials. The central recommendation of this study is that, there is need for policy officials to engage more deeply with teachers in order to understand their actual experiences. In this way, policy changes can begin to reflect school practices and capture the issues that teachers regard as priorities for promoting inclusive initiatives. This view suggests a change to a bottom-up and rhizomatic approach in the way policy is made and implemented because teachers had a feeling of being left out in making decisions that affect their work. To address issues of inequality, ethnicity should form part of future research in order to create different ways of tackling institutional exclusions and build foundations for citizenship and social cohesion.