(Non)-Morse directions in groups

In this thesis, we study Morse directions and the Morse boundary of groups. We start by classifying the Morse boundary of all 3-manifold groups and showing that the Morse boundary of an orientable 3-manifold group only depends on the geometric decomposition of said manifold. This classification requires deep understanding of what it means to be Morse and how to manipulate Morse geodesics. While the theory of Morse boundaries and Morse geodesics is largely developed in analogy with Gromov boundaries, in the rest of this thesis, we focus on phenomena which are unique to the Morse boundary and non-hyperbolic groups. Firstly, we study the (non)-σ-compactness of the Morse boundary. The Gromov boundary of a group is always compact. In contrast, the Morse boundary of a group is only compact if it is empty or the group is hyperbolic. However, the Morse boundary exhibits more nuanced behaviour. Namely, we show that there are groups whose Morse boundary is σ-compact and groups where it is not. We give a full characterisation, which is purely combinatorial in terms of the presentation, of σ-compactness of the Morse boundary for classical small-cancellation groups. This can be used as a way to distinguish small-cancellation groups up to quasi-isometry. Furthermore, we show that for C ′ (1/9)– small-cancellation groups, the group satisfying the Morse local-to-global property is equivalent to its Morse boundary being σ-compact, implying that the topology of the Morse boundary has surprising implications on the concatenability of Morse geodesics. Secondly, in hyperbolic groups all geodesics are strongly contracting. This is precisely not the case for non-hyperbolic groups. We develop the notion of “anti-contracting geodesics segments”, that is, geodesic segments which are intrinsically not strongly contracting. We not only show that for any geodesic metric space, coning-off all anti-contracting geodesic segments results in a hyperbolic space (which we call the contraction space) but also show that if a finitely generated group acted properly on the geodesic metric space, then its action on the contraction space is non-uniformly acylindrical. Moreover, if the action was geometric and the original space was Morse-dichotomous (that is, all Morse geodesics are strongly contracting; this is the case in CAT(0) spaces and injective metric spaces), then the action on the contraction space is a universal WPD action

System justification in action : banal ideology and the rhetorical mobilisation of democracy in UK parliamentary debates concerning Brexit

This thesis critically engages with System Justification Theory (SJT) and Banal Nationalism. SJT demonstrates that ideological beliefs motivate people to either preserve or challenge the status quo. There is however limited research considering how system justification can be understood as an observable process. System justification can instead be re-conceptualised from a relatively static cognitive-motivational construct to a dynamic process enacted in discourse. Banal Nationalism meanwhile demonstrates that individuals treat nation-states as natural entities around which to organise human affairs. The concept of banality is however not exclusive to nationalism because it has the potential to be applied to other forms of ideology. I aim to address this by showing that democracy is taken-for-granted as a natural feature of the UK’s political system. The data were drawn from the official Hansard records of UK House of Commons debates relating to the ‘European Union (Withdrawal) Act.’ To capture system justification in action, and show the banality of democracy, I used a discursive-rhetorical psychological framework to analyse 22 debates. The banality of democratic ideology is indicated by politicians treating democracy as a universal value which does not need to be justified. System justification in action was demonstrated when politicians from left- and right-wing parties constructed the status quo and depicted themselves as either preserving or challenging it to achieve rhetorical goals. By demonstrating both the banality of democracy and system justification in action, this thesis warns social psychologists against accepting discursive and rhetorical psychology’s seminal work on ideology without question

3D and 4D inversion for rock and fluid properties using deep learning

This thesis focuses on estimating rock and fluid properties from the perspective of 3D and 4D seismic inversion. I developed two techniques that enable seamless integration of 3D and 4D seismic data. The first technique emphasises the estimation of porosity, Vclay, and hydrocarbon saturation directly from 3D seismic data using deep learning. Additionally, I propose an approach to enhance the lateral continuity of these estimated petrophysical properties. The products from this first technique are subsequently integrated into the 4D domain, leading to the development of the second technique that enables the inversion for reservoir pressure and saturation changes from 4D seismic data using deep learning. Both techniques involve the use of synthetic training datasets for network training, where the detailed processes for building realistic training datasets are presented. The first technique was tested across four fields with diverse deposition environments, covering meandering fluvial systems, fluvial estuaries, deepwater settings, and carbonate platforms. The second technique was applied to the meandering fluvial field with available 4D seismic data. This technique successfully distinguishes pressure effects from saturation-related effects in the 4D seismic response. It also highlights the importance of incorporating fluid flow information into the training dataset, enabling the network to capture the relationship between the superimposed effects of dynamic property changes and the corresponding 4D seismic response. Finally, I present a summary of the cost-benefit analysis of these developed techniques, demonstrating their ability to accelerate the inversion process in terms of turnaround time while providing robust solutions when applied to field applications

Advancing techno-economic assessment for emission reduction technologies in the cement industry

The cement industry, characterised by low profit margins, accounts for approximately 7% of anthropogenic greenhouse gas emissions and has the highest carbon intensity per unit of revenue among all industries. To achieve full decarbonisation of this sector, it is essential to develop economically viable strategies that incentivise CO2 emission reductions. To guide policymakers and decision-makers from industry or academia in search of decarbonisation strategies, ex-ante system analysis tools including techno-economic assessments (TEA) are essential. This thesis advances techno-economic assessments of emission reduction technologies in the cement industry, both by conducting crucial assessments that have been lacking in this field (e.g., investigating potential business cases for CO2 mineralisation technologies) and by providing guidance for modellers on good and maybe bad practices in TEAs of emerging technologies, aiming to provide actionable insights for policymakers, industry decision-makers, and researchers. The research addresses three key questions, each explored in a peer-reviewed article. First, it evaluates the role of CO2 mineralisation in creating economically viable pathways to net-zero emissions. The results indicate that CO2 mineralisation using virgin minerals could reduce emissions by 8-33% at optimal plant sizes, with potential for profitability when supplementary cementitious materials (SCMs) are produced. This suggests CO2 mineralisation could be a transitional technology in the decarbonisation of cement production. Second, it demonstrates the critical role of uncertainty analyses in TEAs, advocating for the use of global sensitivity analysis methods to enhance transparency and reliability in decision-making. Third, it assesses least-cost decarbonisation strategies across different European regions using geospatial modelling, considering plant locations and potential synergies between industrial actors. The results highlight significant regional cost variations and underscore the importance of coordinated efforts among industry stakeholders to minimise decarbonisation costs. Overall, this thesis provides actionable insights into economically viable emission reduction strategies in the cement industry while offering methodological advancements for TEAs . By integrating uncertainty analyses and geospatial considerations, it contributes to the development of robust, evidence-based decarbonisation pathways.Heriot-Watt University scholarshi

Strong relationships matter : how female entrepreneurs grow and leverage social capital in the German consulting sector

Social capital is vital for entrepreneurial success, and female entrepreneurs, as a significant emerging group in the start-up ecosystem, face unique challenges due to social role expectations, gender bias, and financial limitations. Despite this, they build and manage sustainable businesses, particularly in Germany’s consulting sector, where traditional gender roles persist. However, there is limited understanding of how female entrepreneurs grow and leverage social capital. This study explores how female entrepreneurs in Germany's consulting industry develop and leverage social capital for business growth. Drawing on the theories of Bourdieu (1983, 1986 & 2000), Skeggs (1997, 2004), and Granovetter (1983), this research employs a case-based approach to examine female entrepreneurs' particular experiences. Semi-structured interviews, analysed through thematic analysis, provided in-depth insights (Braun & Clarke, 2006). The study contributes to understanding how female entrepreneurs navigate social relations, how societal factors influence their practices, and how the consulting sector's dynamics shape their approaches. Findings highlight that female entrepreneurs prioritize strong ties, differing from typical business networks that rely on weak ties. Strong ties also enable barter, a common practice in the consulting industry. Additionally, they face gender-specific challenges while benefitting from female role models

Simulation of Wishart processes and generalised Heston models

The topic of this work is in studying the Wishart processes in the extended Heston model framework, which is commonly used as a pricing tool in finance. A volatility process, which is driven by the Wishart process, is simulated by the exact splitting scheme of Ahdida and Alfonsi [2]. We enhance their approach by adding the component of a time integral of volatility to the existing generator of the Wishart process. We also avoid the expensive matrix exponentiation procedure, that Ahdida and Alfonsi [2] state about, by the change of measure approach from Malham et al. [50] and Gnoatto and Grasselli [28]. Using the composition techniques from Ninomiya and Victoir [55], we construct the three new schemes to sample the pairs of volatility and its time integral. One of the schemes has a local error of order two, whereas the other two schemes are based on the Strang splitting with the local errors of order three. The change of measure approach of Gnoatto and Grasselli [28] helps us to transfer between the restricted and full parameter cases of the Wishart processes. The sampled pairs of volatility and its time integral are then used during the pricing procedure. Comparison of the moment generating functions with Gnoatto and Grasselli [28], and comparison of the call option prices with Leung [45], are used to show a correctness of the implemented schemes.EPSRC Centre for Doctoral Training in Mathematical Modelling, Analysis and Computation (project reference EP/S023291/1) grant 2277802

Long-term performance assessment and future proofing of a raingarden for stormwater management

Raingardens are a type of Sustainable Drainage Systems (SUDS) that provides a nature-based solution to stormwater control. Research into the performance of raingardens is relatively scarce in the UK and effort is needed to provide data and improved scientific understanding to deliver a strong evidence-base. The overarching goal of this study is to evaluate the long-term performance of a raingarden, designed over a low-conductivity soil. To this effect, an experimental raingarden with two amended soil types (Sandy loam with 24% fines content; Loamy sand with 13% fines) was installed within the Royal Botanic Garden Edinburgh (RBGE) in Scotland, and monitored between Summer 2019 and Winter 2022-23. This study documents the qualitative and quantitative methods in evaluating a field scale raingarden. Antecedent soil moisture between storm events, saturated hydraulic conductivity, and climate season were found to be key factors that controlled surface ponding in the sandy loam media. The time to drain ponded water in this media in Winter was on average twice longer than that of Summer due to 71% lesser median percolation in the cold season. In comparison, loamy sand media exhibited a lesser influence of temperature on infiltration, with average values in Winter being 40% lower than those in summer. Computer model of the raingarden developed in this study predicts that infiltration in the sandy loam soil must be at a minimum of 64 mm/h to prevent overflow from the raingarden under a reasonable worst- case scenario projected for 2050. The efficiency of evapotranspiration (ET) removal on rainfall was on average of 43% in summer highlighting the significance of the role of vegetation in the hydrological cycle of the raingarden. Species Festuca altissima, Primula posioni and Ligularia fischeri, Rodgersia pinnata and Gunnera manicata were found not suitable in a raingarden setting due to either stringent habitat requirements or prone to wilting during prolonged dry periods. Organic wood mulch is preferred over gravel mulch as the later potentially increases the solar radiation exacerbating heat stress in times of drought. Overall, the results of this work indicate that raingardens installed over low-conductivity soils can still be an effective technology for stormwater management, when designed suitably. The findings of this work provide clear and transferable insights that can be applied to the design, monitoring and maintenance of raingardens in similar climatic and soil conditions, both in the UK and around the world

Characterisation of porosity and permeability in reservoir seals using an experimental and upscaled modelling approach

Carbon capture, utilisation, and storage (CCUS) provide a safe option to achieve net zero carbon emission in 2050. Captured CO2 is usually stored in a deep geological reservoir formation, overlain by a sealing formation known as caprock. Understanding caprock integrity is important in ensuring safe and long-term CO2 containment and storage. Therefore, this research aims to reduce the uncertainties/risk due to the caprock integrity via comprehensive characterisation analysis. However, since caprock is comprised of micropores and nanopores with very low permeability (less than one microDarcy or 10E-18 m2 ), conventional porosimeter and permeameter are not suitable to determine its porosity and permeability. In addition, coring operation in the caprock section is very difficult and expensive, leading to the limited or unavailability of preserved core samples for laboratory analyses. Hence, data from drill cuttings and well logs are used as alternatives when core samples are limited or unavailable. In this research, caprock core samples, drill cuttings, and well log data were selected from S Field, located in offshore East Malaysia, because it is one of the candidates for a CO2 storage site, with a total of 4 wells, including an appraisal well drilled in 2015. This study is comprised of experimental rock characterisation, analyses of well-log data integrated with lab data, and numerical modelling of advective CO2 transport. The rock characterisation analyses include x-ray diffraction (XRD), x-ray fluorescence (XRF), particle size analysis (PSA), thin section petrography, scanning electron microscopy with energy dispersive x-ray (SEM-EDX), low-pressure N2 (LP-N2) sorption analysis, mercury intrusion capillary pressure (MICP), nuclear magnetic resonance (NMR), unsteady state (USS) pulse decay, and helium pycnometry (HP). In addition, broad ion beam (BIB) and focused ion beam scanning electron microscopy (BIB-SEM) were used for digital core analysis (DCA) of caprock samples. Next, well log data from S Field was analysed and integrated with lab data to generate porosity and permeability trends of the caprock of S Field. The data was also used to calculate capillary entry pressure and CO2 column height as part of the caprock integrity assessment. Finally, we studied advective transport of CO2 in S Field using Peng-Robinson (PR) equations of state (EOS) and multiphase fluid flow method. The caprock of S Field has been identified as siltstones since it is dominated by quartz and silts from mineralogical analyses. The caprock is split into two facies, Seal A and Seal B, with differing percentages of clay minerals (20% and 40%, respectively). Seal A is shallower and lies between 800 and 1400 meters below the seafloor. Seal B, on the other hand, is situated between Seal A and the carbonate reservoir and has a burial depth of around 1400 to 1900 meters. The permeability and porosity values determined in the lab, however, do not differ substantially between the two facies. This could be because Seal B is considerably over-pressured compared to Seal A. This excessive pressure could lead to the preservation of porosity during compaction, consequently resulting in enhanced permeability. This finding is consistent with the time-to-depth conversion from seismic data, which identifies Seal B as being less compacted than Seal A. Based on the data integration of the calculated porosity, permeability, capillary entry pressure, and column height, it can be summarised that the seal layers of S Field can contain injected CO2 as long as the reservoir capacity is not exceeded. This finding is supported by the numerical flow models, which show no leakage across the seal in 10,000 years and contained leaks in 1 million years

The lived experience of disabled academics with energy-limiting chronic impairments (ELCI)

Despite the Equality Act 2010 and the Public Sector Equality Duty, disabled academics report experiencing a range of barriers to pursuing an academic career. Such barriers apply to those with visible and non-apparent impairments, such as ‘Energy-limiting chronic impairments’ (ELCI). Similarly, and consequently, the lived experiences of disabled academics are under-researched. The social-relational model of disability (SRMD) was embraced as the theoretical framework for this study. Using a multi-method qualitative approach, this study overtly observed the disability intervention (DISC) project to explore the lived experience of disabled academics with ELCI. The semi-structured interviews with participants/stakeholders and the observational data from DISC were thematically analysed. Indeed, hidden impairments among academics are poorly disclosed in universities, resulting in institutional structures failing to meet their needs, particularly those living with ELCI. This study contributes defeatism as a systemic impact of management practice that is socially imposed. It inevitably leaves disabled academics to self-exclusion or self-managing ‘impairment effects’ in universities, which is worth considering for improving disability inclusion with equitable support in UK universities. The broader implications of the findings point that universities should adopt proactive attention to social-relational barriers. Further, universities should also consider systemic change to indirect discrimination in disability management practice.Engineering and Physical Sciences Research Council (EPSRC

Computational modelling of ruthenium catalysed C–H alkylation of heteroarenes

A mechanistic study of the C–H alkylation of 2-phenylpyridine (2-ppy) using alkyl halides and catalysed by [Ru(2-ppy)(MeCN)4] + has been carried out using density functional theory (DFT). A general mechanism has been proposed for the reaction of primary alkyl halides, modelled as 1-bromopropane, in the presence of a carboxylate additive (Chapter 3). Following C–H activation and cyclometallation via deprotonation by the additive, an SN2 mechanism was identified for the C–Br activation step, leading to an ortho-alkylated product after reductive coupling and product release. The latter has been identified as the rate-determining step in catalysis. Subsequently, the role of the carboxylate additive has been assessed by studying the above reaction in its absence (Chapter 4). The results have shown that the substrate can perform the deprotonation. It was found that the rate limiting-determining step in catalysis becomes the formation of the C–H activation precursor, but the C–Br activation is not significantly affected. A complete mechanistic study of the C–X activation (with X = Cl, Br, I) of 1- chloro-, 1-iodo-, 2-bromopropane and 2-bromo-2-methylpropane in the presence of a carboxylate has also been performed (Chapter 5). While the nature of the halide does not significantly influence either the mechanism or the selectivity of the reaction, it was found that secondary and tertiary alkyl halides can follow a radical mechanism, affording some or exclusive meta-alkylation. Finally, the key results obtained in this thesis have been subjected to a benchmark study, compared against the available experimental data (Chapter 6), and GGA functionals have been proposed as the most appropriate method for this system