VictorJuiz/thesis huggingface dataset:
“A love-hate relationship”: Canadian laypeople’s construction of academic theories as diffusing innovations

As the knowledge society paradigm and its emphasis on knowledge as socioeconomic capital grows, the importance of subtle, collective sharing of ‘blue skies’ academic theories is sidelined. Non-expert voices are largely marginalized in these discussions of what academic knowledge is or should be. In order to bridge gaps between academia and laypeople, and basic research and impact, this study explored how Canadian laypeople construed the popularity of academic theories across domains of physical sciences, social sciences, and the humanities, and related those perceptions to a novel measure of diffusion. An integrated mixed-methods research design was framed by a constructionist philosophy and a conceptual framework rooted in Diffusion of Innovations literature, re-conceptualizing academic theories as constructed innovations. Ninety academic theories were input into Google Trends, which provided data regarding the frequency with which Canadians searched theory terms. This was used as a measure of initial diffusion. Repertory grids were produced with the completion of online interviews with fifteen Canadian laypeople, which captured the qualities of academic theories that they understood as being related to popularity. Qualitative analyses revealed that Canadian laypeople had complex, mixed feelings about whether theories were beneficial or irrelevant. Cluster analyses identified themes of ‘the nature of discussion’, ‘benefits’, ‘acceptance of the best knowledge’, ‘explanation of something meaningful’, ‘understandability’, ‘physically verification’, ‘scientific proof’, ‘religious belief’, and ‘applied use’ as being used by laypeople to contrast the popularity of academic theories, the first three of which were most closely related to the initial diffusion of theories. Overall, the conceptual framework of innovations attributes from Diffusion of Innovations literature proved to be a fruitful application.

Keywords: diffusion of research
diffusion
laypeople
theories
Advisor: Brennan, J
Characterisation of armour ceramics at the microstructural scale for modelling of impact

The present DPhil thesis aims to provide new insights into the deformation and failure mechanisms of armour ceramics by carrying out experimental investigations at the microstructural scale, which can be integrated into numerical modelling to enhance its predictive capability for ceramic armour designs.
Grain size distributions of polycrystalline alumina with varying microstructures were characterised precisely by employing the method of digitising grain contours from SEM images. The experimental results were incorporated to develop an innovative algorithm for generating representative numerical microstructures, and to validate the numerical models via a novel method of virtual cross sectioning.
The effect of shear stresses on brittle failure of grain boundaries was investigated by measuring the strengths of grain boundaries of alumina in combined normal and shear loading. The contribution of the shear component was found to be significant, which overthrew known theories usually adopted in micromechanical modelling that assume otherwise.
Progress towards making reliable toughness measurements of individual microstructural components was made by allowing for, or avoiding the effect of focused ion beam (FIB) damage at notch roots through the following methods.
(a) Enabling stable crack growth allowed the stress intensity factor for crack propagation Kp to be measured reliably in Al2O3 and SiC. Kp measured in vacuum represented Kc, giving values of 2.8 MPa∙√m for a-plane sapphire. Kp measured in air was 1.8 MPa∙√m for both a- and m-plane sapphire, and 2.2 MPa∙√m for (1̅100) plane SiC. The value was reduced substantially by moisture-assisted subcritical crack growth (SCG) and was close to K0, with crack velocities on the scale of 10-8 m/s. Additionally, cyclic loading tests in vacuum demonstrated the self-healing of interfaces in alumina.
(b) Clarification of the extent of the effect of the implantation damage. First, a microstructural investigation of Ga+- and Xe+-FIB damage induced in Al2O3 and SiC exhibited the formation of amorphous and crystalline damaged layers, which were determined by the combination of ion species, target material and FIB settings. GaAlO3 particles and Xe bubbles were found in Al2O3 implanted by Ga+ and Xe+, respectively. Second, Ga+ and Xe+ implantation stresses (IS) were quantified in Al2O3, SiC and Si using a beam-curvature method, and were mostly on the scale of GPa. With increasing ion dose, while the Ga+ IS in Al2O3 and SiC remained compressive, Ga+ IS in Si and Xe+ IS in Al2O3 and SiC transited from compressive to tensile. For fracture toughness measurement, Ga+-FIB was recommended for notching all three materials investigated.

Keywords: Numerical simulation
Deformation and failure mechanisms
Ceramics
Microstructural characterisation
Micromechanical testing
Advisor: Todd, R
Petrinic, N
Bose gases in double-well potentials

This thesis presents experimental results which utilise multiple-radiofrequency-dressed potentials as a method of confinement for cold atoms, and details progress towards investigations of the out-of-equilibrium dynamics of two-dimensional systems.
This work has demonstrated the matter-wave interference of Bose gases released from a double-well potential. We investigate the scaling of the matter-wave inteference fringe wavelength, verify the coherence of the experimental procedure, and demonstrate the controllability of the multiple-radiofrequency-dressed potentials to load a prescribed fraction of atoms into each potential well. Methods presented elsewhere were also used to produce two-dimensional Bose gases in the Berezinskii-Kosterlitz-Thouless regime. We present a discussion of phase correlations in two-dimensional Bose gases, including their time-dependent behaviour as the system equilibrates following a quench.
Radiofrequency-dressed potentials are intrinsically state-selective, as we demonstrate through manipulations of a mixture of Rb-87 atoms in different hyperfine states within a double-well potential. This can be used to implement species-selective potentials and is a promising architecture for future experiments concerning impurity physics. We find this mixture to be long-lived in the radiofrequency-dressed potential, in stark contrast to recent experiments on this apparatus, in which mixtures of radiofrequency-dressed Rb-87 and Rb-85 were found to suffer from very fast inelastic loss.
Furthermore, we describe the application of machine learning methods to optimise the experimental sequence, in particular the stages of laser cooling and evaporative cooling which are necessary to achieve a quantum gas. We compare several machine learning methods, including Artificial Neural Networks and Gaussian Process regression, and determine experimental parameters which have the strongest influence on the desired outcome. We focus our efforts initially on producing Bose-Einstein condensates with very large atom numbers, although we later highlight the versatility of this method by improving other metrics, such as sequence repetition rate or the final temperature of the gas.

Keywords: Bose-Einstein Condensates
Quantum Gases
Machine Learning
Advisor: Foot, C
Cost semantics for heterogeneous parallel functional languages

In today's world parallelism is ubiquitous, and different types of parallel models and processors are becoming increasingly common. Moreover, while our programs become increasingly heterogeneous in the parallelism they employ, user-visible parallelism in our languages becomes increasingly homogeneous, with the parallelization onus put more and more on the compiler or runtime. This increasing divide between what is seen and what happens in our languages makes being able to determine the costs of running the same program on different types of hardware evermore important. And, in such a world, having the means to profile programs by their underlying semantic properties is crucial.
However, while there are means of semantically profiling parallel programs written for the CPU, there are still no means to profile and reason about parallel programs that use multiple types of parallel processor based upon their underlying semantics. In this dissertation, we set out to solve this problem by presenting a cost semantic theory that allows profiling for both time and space in heterogeneous parallel programs, while also allowing higher-order constructs on the GPU. Specifically, in this dissertation we develop cost semantics for region-based heterogeneous parallel functional programming languages. We do so by developing it for a core calculus that is readily extendable to other functional programming languages.
In order to develop a cost semantics for such a language, we first develop a novel cost semantics for a region-based homogeneous-parallel functional language residing on the CPU, along with a novel trace-based cost semantics for a similarly region-based homogeneous-parallel functional language residing on the GPU. We then develop and present a way to glue together these two languages that reside on different computational realms---statically, semantically, and operationally---to arrive at a region-based heterogeneous parallel language, and a cost theory that is able to profile programs written in that language. We then implement and evaluate our theory and show that it accurately reflects the real-world runtime characteristics of source programs.

Keywords: functional programming
semantics
parallel computing
functional languages
parallelism
programming languages
cost semantics
Advisor: Gibbons, J
Black soldiers in the Rhodesian Army 1956-1981: The loyalties of professionals

During Zimbabwe’s war of liberation, the regular Rhodesian Army was, paradoxically, dominated by black soldiers. These soldiers have long been chastised as collaborators and ‘sellouts’ of dubious motive, or their service rendered in neo-Rhodesian accounts as an endorsement of Ian Smith’s racist regime. This thesis argues that such conceptions are fundamentally wrong. Instead, it contends that these troops possessed loyalties that were particular to regular soldiers.
These comprised ‘regimental loyalties’, in which black soldiers’ allegiance was pledged not to the Smith regime, but instead to their unit, and only then to the wider Rhodesian Army. ‘Regimental loyalties’ were undoubtedly important, however during combat they were superseded by another set of solidarities at the micro-level. I argue that black Rhodesian soldiers abided by an ethos of what I term ‘professionalism’, in which their military efficacy was inextricably linked to their deep bond with their comrades. These ‘professional’ loyalties were forged only once within the military milieu, through intensive and lengthy processes of training and military socialisation.
These ‘regimental’ and ‘professional’ solidarities distinguished black Rhodesian soldiers from other types of combatants during the war. Despite the systematic racism of the Rhodesian Army, these loyalties remained strong, largely as the regiment in which most served, the Rhodesian African Rifles, possessed a distinctive military culture. I argue that, as the conflict wore on, experiences of combat, and guerrilla targeting of black soldiers and their families, cemented these loyalties. My interviewees characterised their service as ‘apolitical’, and I contend that it was both this ‘apolitical’ status and their military proficiency that led to black Rhodesian soldiers being retained by Robert Mugabe’s government after independence. During Zimbabwe’s tumultuous first two years they played a key role fighting for a government headed by their erstwhile wartime enemy, which my interviewees argued demonstrated the enduring power of their soldierly loyalties.

Keywords: Zimbabwe War of Liberation
Black soldiers in the Rhodesian Army
Politics of memory
Counter-insurgency conflict
Rhodesian African Rifles
Wars of decolonisation
Zimbabwe
Oral history
Soldierly loyalty
Military professionalism
War narratives
Advisor: Alexander, J
Synthesis of low dimensional boron nitride nanomaterials for thermal management applications

This thesis investigates the synthesis of boron nitride (BN) nanomaterials using the chemical vapour deposition (CVD) technique, in order to propose an efficient means of generating high-quality BN nanomaterials of different morphologies whose properties can be controlled, so that they can be optimised for real-world applications, particularly for thermal management.
It is found out that the growth of BN nanotubes (BNNTs) followed a tip-growth mechanism and this was confirmed by varying the duration of reaction studied through scanning electron microscopy (SEM). This study shows that the powder precursor of boron and magnesium oxide generated gaseous boron oxide and magnesium that was found to be deposited on the surface of the SiO2 target substrate in the form of magnesium borate. This observation was investigated by thermal gravimetric analysis (TGA), energy-dispersive x-ray spectroscopy (EDX), and X-ray photoelectron (XPS) depth profiling. The lower melting point of magnesium borate compared to the synthesis temperature enabled the formation of catalyst droplets that was found to be crucial to generating the nanotubular structure. Hindering the formation of catalyst droplets resulted in the synthesis of BN nanosheets. Hybrid one-dimensional nanostructures such as BNNTs coated with CNT were synthesised by adding methane as carbon source in the synthesis.
The properties of BN nanomaterials can be tailored by controlling their morphology that has been observed by the increase of thermal conductivity of BN nanotubes compared to BN nanosheets at the same weight percent in isopropanol that was measured using the transient plane source (TPS) method. These controllable properties make BN nanomaterials a promising material that can be used as fillers in composites and liquid solutions for thermal management and other applications.
Performing Density Functional Theory (DFT) calculations showed insights regarding BN bond formation and it was found out that a small difference of energy barrier was present between the synthesis with and without the catalyst droplet, from which it can be inferred that BN bond formation can still occur in the absence or presence of the catalyst droplet. BN bond formation occurring on the MgO (100)-(111) step-edge surface was shown to have more stable energy than those on the MgO (111) facet surface, which led to the development of zigzag chirality. These theoretical findings are found to be in good agreement with the empirical results. Lastly, it was found out that the activation energy for BNNT growth is 58.88 kcal/mol by correlation of the growth rate and the Arrhenius equation.

Keywords: Chemical Vapour Deposition
Growth Mechanism
Boron Nitride Nanotubes
Thermal Conductivity
Advisor: Nicole, G
Wrinkling instabilities: modelling, analysis and computation

Wrinkling is a universal instability occurring in a wide variety of engineering and biological materials. Despite extensive study across different systems, a full description is still lacking, particularly in the case of growing materials. Most studies consist of some combination of a substantially simplified elastic model, an analysis that does not go beyond first order, and numerical simulations in commercial software packages that do not necessarily correspond to the mathematical system studied. This thesis addresses all three of these shortcomings by providing a systematic analysis of a fully hyperelastic bilayer past the linear stability threshold into the weakly nonlinear regime, along with a carefully discretised numerical bifurcation analysis of the system.
For comparison, we assume that wrinkling is generated either by the isotropic growth of the film or by the lateral compression of the entire film-substrate system (both in plane strain). We adopt a stream-function-based formulation and perform an exhaustive linear analysis of the wrinkling problem for all stiffness ratios and under a variety of additional boundary and material effects. Namely, we consider the effect of added pressure, surface tension, an upper substrate, and fibres. We obtain analytical estimates of the instability in the two asymptotic regimes of long and short wavelengths.
We then carry out a weakly-nonlinear analysis to derive an amplitude equation that describes the evolution of the wrinkling amplitude beyond the bifurcation point, followed by a comprehensive numerical bifurcation analysis of the problem using the finite element method. We demonstrate excellent agreement between the weakly-nonlinear analysis and the numerical experiments and are also able to directly solve for the bifurcation point in our discretised system and characterise the effect of implementation details such as the aspect ratio of the computational domain on the observed bifurcation point.
We then explore solutions of the amplitude equation in the case that the wrinkling amplitude is allowed to vary over long spatial and/or temporal scales. Finally, we demonstrate that our numerical experiments are able to identify secondary bifurcations in the system similar to those observed in experiments for which analytical methods have thus far been unable to provide a complete explanation.

Keywords: solid mechanics
wrinkling
amplitude equation
finite element method
perturbation methods
weakly nonlinear analysis
nonlinear elasticity
bifurcation analysis
morphoelasticity
Advisor: Goriely, A
Farrell, P
Patterns of settlement in the early prehistory of Cyprus

The present Thesis examines certain aspects of settlementpatterning in the earlier prehistory of Cyprus by reference to one particular problem, namely the absence in Cyprus of those tell-formations so characteristic of neighbouring countries in the Levant. Although much of the discussion concentrates on this central problem, its empirical basis takes the form of a Catalogue of all Sites and Finds of the period under discussion. An Introduction to the Catalogue explains the sources from which it is compiled, the entries listed under each Site, and the Code of attributes by reference to which the archaeological material is described. Various Appendices to the Catalogue collate the information in earlier publications where inconsistent with the method of recording or with the criteria for inclusion which have been adopted here.
Continued in thesis ...

Keywords: antiquities
prehistoric
Neolithic
land
Cyprus
patterns
settlement
peoples
Advisor: Britton, D
The ecology and behaviour of closely related species in Gibraltar (with special reference to swifts and warblers)

Bird communities at Gibraltar are examined and the ecology and behaviour of two species pairs which dominate numerically, the Blackcap Sylvia atricapilla and the Sardinian Warbler S.melanocephala in Matorral, and the Swift Apus apus and the Pallid Swift A.pallidus in the air, are compared.
The communities exhibit seasonal changes in species and biomass probably due to habitat seasonality and geographical location, The latter in part produces the large migrant element in the communities. Largest seasonal fluctuations occurred in the simplest habitats. The number of species which potentially interacted with the two species pairs studied changed with season, The communities at Gibraltar differ from those studied by others elsewhere in the Mediterranean Basin.
The Blackcap and the Sardinian Warbler are resident and exhibit morphological deviations from other known forms. The local Blackcap population is intermediate morphologically between the Sardinian warbler and the nominate Blackcap population, which arrives at Gibraltar in winter, The life cycle of the residents is related to climatic conditions, food supply and the presence of migrants. The two species overlap extensively in resource use but the Sardinian Warbler is broader-niched. Interspecific aggression end territoriality spaces individuals all year. Resident warblers accumulated fat during favourable periods, Mortality was high in both species, Northern Blackcaps returned in successive winters.
Swifts exploited seasonal resources and left in autumn. Life histories are modified accordingly. Overlaps in resource use are high but there is spacing out of groups. Pallid Swifts are less specialised than swifts and remain longer at Gibraltar, raising two broods instead of one. Pallid Swift mortality is low but higher than for Swift.
The two pairs studied may not be in equilibrium and behavioural interactions maintain resources partitioned. The question is raised as to whether territoriality is related to competition or to interference.

Keywords: swifts
ecology
Blackcap
behaviour
warblers
species
Gibraltar
Advisor: Perrins, C
Pan-Islamism during the Cold War: the case of Turkey & Pakistan

On the face of it, Turkey and Pakistan seem to have little in common today, except for the fact that both countries have a Muslim majority population. Turkey, despite concerns over a rising tide of Islamism, is still perceived of as a country that is constitutionally secular and who sees her future with the West and Europe. Pakistan, on the other hand, continues to fight Islamic fundamentalism at home, is still struggling to reach a consensus on exactly what sort of role religion should play within the state and is increasingly clubbed together in international circles with that quintessential struggling state, her northern neighbour, Afghanistan.
[Introduction continues in thesis]
Numerical approximations for stochastic differential equations

In this thesis, we consider problems related to the numerical simulation of stochastic differential equations (SDEs). In particular, we are interested in methods that use both increments and areas of the Brownian path. For example, time integrals of Brownian motion carry useful information whilst being normally distributed and thus straightforward to generate. We will make precise the "path information" contained by such integrals and present a polynomial approximation theorem for Brownian motion. Since the Gaussian coefficients given by this expansion are independent, we can express Brownian motion as a polynomial with additional noise. We shall then use this simple observation to develop high order methods.
The majority of these methods approximate SDEs through the use of ODEs, which can be accurately discretized using state-of-the-art solvers. To numerically demonstrate these approaches, we will simulate four SDEs: Inhomogeneous Geometric Brownian Motion, Cox-Ingersoll-Ross model, underdamped Langevin equation and the Lévy area of Brownian motion. The code for these examples can be found at github.com/james-m-foster.
We also study problems related to variable step size methods for SDEs. Most notably, we investigate which numerical methods and variable step size strategies can ensure pathwise convergence to the true SDE solution. Our analysis is based on rough path theory and requires methods to be locally close to an ODE driven by a piecewise "Brownian polynomial". This result can therefore be applied to the Heun and midpoint methods. In order to prove convergence, we will require variable step size strategies to produce a nested sequence of partitions with mesh size tending to zero.

Keywords: Orthogonal polynomials
Brownian motion
Stochastic differential equations
Numerical approximations
Lévy area
Variable step size methods
Langevin dynamics
Inhomogeneous geometric Brownian motion
Cox-Ingersoll-Ross model
Advisor: Oberhauser, H
Lyons, T