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Geospatial Inference and Management of Utility Infrastructure Networks
Get PDFPh. D. Thesis.Modern cities consist of spatially and temporally complex networks that connect urban infrastructure assets to the buildings they service. Critical infrastructure networks include transport, electricity, water supply, waste water and gas, all of which play a key role in the functioning of modern cities. Understanding network spatial connectivity, resource flow, dependencies and interdependencies is essential for infrastructure planning, management, and assessment of system robustness and resilience. However, there is a sparsity of fine spatial scale data from which such understanding can be derived or inferred. Often data is held within commercially sensitive organisations and may be incomplete topologically and/or spatially. Thus, there is an urgent need to develop new approaches to the integrated inference, management and analysis of the complex utility infrastructure networks. Such approaches should allow the highly granular representation of utility network connectivity to be represented in a spatially explicit manner, employing methods of data and information management to ensure they are scalable and generic.
This thesis presents the development of such an approach, one that employs a geospatial ontology to formally define the key entities, attributes and relationships of fine spatial scale utility infrastructure networks. This ontology is used as the conceptual framework for the development of a suite of algorithms that allow the heuristic inference of the spatial layout of utility infrastructure networks for any urban conurbation within the UK. This is demonstrated via several case studies where the electricity feeder network between substations and buildings is generated for several different cities within the UK. Validation against the known network for the city of Newcastle upon Tyne indicates that the network can be inferred to high levels of accuracy (about 90%). Moreover, the algorithm is shown to be a transferable to the inference and integration of other utility infrastructure networks (gas, water supply, waste water, and new road layouts).
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The representation, management and analysis of such spatially complex and large utility networks is, however, a major challenge. The efficient storage, management and analysis of such spatial networks is explored via a comparison of a traditional RDMS approach (PgRouting within Postgres), spatial database (PostGIS) and a NoSQL graph-database (Neo4j), as well as a bespoke hybrid spatial-graph framework (combination of PostGIS and Neo4j). A suite of comparison tests of data writing, data reading and complex network analysis demonstrated that significant performance benefits in the use of the NoSQL graph database approach for data read (around 210% faster) and network analysis (between 420 and 1170 % faster). However, this was at the expenses of data writing which was found to be between 135 and 150% slower.MISTRAL project, School of Engineering at Newcastle University
Inhabiting secularity and postsecularity: Christianity, neoliberal transition, and the intersectional experiences of migrant workers in Shenzhen, China
Get PDFPh. D. Thesis.This thesis contributes to geographies of secularity and postsecularity by examining Christianity and the experiences of migrant workers in Shenzhen, China. In the post-reform era, China appears to be caught in a contradictory dual process – the entrenchment of the secular values and, simultaneously, the notable revival of all forms of religiosity. I argue that this dual transition has opened up new possibilities for examining the relations between secularity and religion beyond the Western trajectory of modernization. This thesis first provides a dialectical analysis of secularity and postsecularity, which views them as distinctive yet mutually constituted epistemologies and conditions of being. I argue that geographers can significantly advance the understanding of secularity and postsecularity by offering geographical knowledge on: (1) the political-ideological project of secularity and how it is inhabited by individuals in the specific process of place-making; (2) what and how new postsecular subjectivities are engendered by, and co-constituted with, secular conditions of being; and (3) the wider socio-spatial conditions where variegated forms of secularity and postsecularity may be re-configured. To address these efforts, this thesis also engages with neoliberalism and intersectionality as analytical tools to explore the complex social and power relations from which secularity operates but also from which new religious subjectivities and agency may emerge.
These inquiries are examined by in-depth ethnographic research with Christian migrant workers in Shenzhen. I elucidate how migrant workers constitute their religious subjectivities by drawing on Christian resources and ethics, which enable them to come to terms with, but also sometimes to reframe and counteract, the neoliberal secularity that normalises them as productive, docile, governable, yet alienated, subjects. In particular, I focus on how migrant workers’ negotiations of religion, class, gender and adulthood mutually shape one another in such a way that postsecular subjectivities and agency are engendered. Although workers’ intersectional religiosity is integral to, and indeed constitutive of, the way in which secularist state developmentalism, autocratic power, and neoliberal labour relations are legitimated, lived and reinforced, it nonetheless also implies a possibility of postsecular reflexivity, which sets an affective condition on the ways that secular powers and normalised subjects actualise as a part of migrant workers’ everyday life. Above all, this thesis not only sheds lights on the specific configurations of secularity and postsecularity in China, but also establishes an intersectional approach to secularity and postsecularity
Novel, Differentiated Antibody Drug Conjugate Warheads from Analysis of the NCI Screening Database
Get PDFPh. D. Thesis.Antibody-drug conjugates (ADCs) combine the selective nature of targeted therapies with
potent cytotoxic warheads utilising linker technology to deliver selectively the warhead to the
target. Proof of concept has already been observed with five licensed ADCs on the market,
giving confidence to the use of ADCs in cancer treatment, with multiple ADCs in clinical
testing. Many of these ADCs consist of cytotoxic payloads derived from complex natural
products, consequently leading to synthetically long and complicated routes.
To address this problem, novel warheads have been identified through screening the NCI
database, that are structurally simpler drugs with differing cellular activity profiles. This may
also address resistance issues. Out of the seven that were identified, three series have been
explored; the nitroacridines (113), the quinolones (106) and thiosemicarbazones (174).
Nitroacridines inherently target hypoxic cells and are known to intercalate with DNA.
Quinolones are known tubulin binders and compounds synthesised have been evaluated in
biological studies. Thiosemicarbazones are metal chelators, sequestering iron and copper.
They inhibit ribonucleotide reductase, inactivating the enzyme leading to cell death.
Work has been carried out to optimise and resynthesize these parent warheads as well as
analogues. The warheads have been coupled to non-cleavable and cleavable dipeptide linkers
(examples shown below) and subsequent conjugation to an antibody, which have been
assessed in cell assays.AstraZenec
Fostering sustainable university-university museum relationships: a study on the integration of museum collections in Higher Education curricula
Get PDFPh. D. Thesis.This study aims to identify conditions which determine the use of museum collections in
university level teaching. The contemporary literature on university-museum collaborations
in the UK focuses heavily on demonstrating the pedagogical advantages of using objects in
teaching, but does little to help others incorporate museum collections into their own
curricula. Although pedagogical barriers can play a role in the use of museum collections in
teaching, there are other determining conditions which can impact an academic’s decision to
pursue such teaching methods. For this study, identified determining conditions were
categorized into four themes. These are: Pedagogy, Logistical Limitations, Museum
Management Structure, and the Student Response.
Four UK-based cases are used for this study. These are: Newcastle University and the Great
North Museum: Hancock, University of Manchester and the Manchester Museum, Oxford
University and the Ashmolean Museum, and University College London and the UCL
Collections. Drawing on qualitative data collected through interviews with academic and
museum staff and university student comments from an online survey, this study examines the
relationships between the four universities and their university museums, and how these
relationships either support or inhibit the use of museum collections in university level
teaching.
In today’s economy, university museums can no longer financially justify their traditional role
of collecting and preserving collections for the sole purposes of academic use and university
superfluity. Not only do university museums need to prove their worth to their parent
university, but the social impact of university museums is also a hotly contested topic in
today’s museum sector with more and more university museums shifting their focus to the
public to secure necessary funding. This study argues that this pedagogical shift can cause
tensions between the museum and the university, and consequently, hinder the use of museum
collections in university curricula. As a result, this study identifies the concepts of awareness
and staffing amongst the university and university museum as key areas to reevaluate and
prioritize to create more sustainable links and support the use of museum collections in
university curricula
S-N Curves and fracture mechanics based fatigue assessment of offshore floating wind turbines
Get PDFPh. D. Thesis.With increasing water depth in offshore applications, the traditional fixed wind turbines have a higher cost in design safety and energy production. Therefore, several concepts of offshore floating wind turbines (FWTs) have been proposed. However, these kinds of structures are prone to fatigue damage due to harsh environmental conditions. The objective of this thesis is not only to quantify the fatigue damage predicted by different methods but also to provide a basis for the currently immature procedure of fatigue assessment of FWTs.
The traditional S-N curves and fracture mechanics (FM) based fatigue assessment approaches are widely used in offshore fixed wind turbine systems. However, hydro-elastic loads and coupled loads between floating platform and mooring system cannot be ignored in FWT system. The wave and wind induced loads are highly related to the structural motions and responses and the instantaneous position should be updated with the changes of hydrodynamic and aerodynamic forces all the time. Moreover, the structure response amplitude increases at the nature frequency and nature eigen-frequency. These factors bring a lot of challenges in the fatigue assessment of offshore FWTs.
Due to a lot of non-linearities in FWT systems, the fully coupled aero-hydro-servo-elastic analysis is conducted with use of FAST software to obtain the time history of structural dynamic response. Then the fatigue life is calculated by Rainflow counting method with related S-N curves and Miner’s rule. A simplified lumping approach combined with joint probability of wind and waves is utilized to reduce large amount of computational time. Only 498 load cases have a probability of 0.1 ‰ and higher which makes the time-domain analysis more efficient and accurate. The total probability of occurrence is 98.2% and it is feasible to use these load cases to conduct fatigue calculation. The results calculated by the simplified lumping approach show a good agreement with only 0.91% discrepancy. Although the non-linearities for the entire FWT structure and dynamic control system are taken into account by time-domain analysis, the analysis may end up due to the complicated and time-consuming process. Thus, the spectral fatigue analysis can be regarded as an alternative to the time-domain analysis for the quick fatigue assessment of FWTs. A narrow-band solution and six wide-band solutions are presented and compared. The results show the big discrepancy in fatigue lives compared to the results predicted by time-domain analysis when use different spectral fatigue models. However, the solution proposed by Tunna has only two parameters which can be considered as the best quick spectral prediction model for FWTs even though the result
is not superior.
FM based analysis is an alternative to predict remaining fatigue lives. It is advanced compared to S-N curves based approaches since it can provide detailed crack growth description. Parametric studies of initial crack sizes, critical crack depths, stress concentration factors (SCFs) and mathematical load sequences are investigated with use of Paris’ equation. Nevertheless, it is found that FWTs are more prone to physical load sequence effect due to the noticeable increases and decreases in mean stress. Therefore, two overload (OL) retardation models are explained and compared based on experimental data. Afterwards, a modified Space-state model is proposed with consideration of threshold stress intensity factor range and fracture toughness which has been applied in the fatigue assessment of a spar-type FWT successfully.
As a summary, S-N curves based approaches can be applied in the design phase of FTWs with consideration of SCFs. But it is not reliable for the reassessment after some years in operation e.g. due to corrosion effect, change of geometry or the variations of material constants which are not described in S-N curves. FM based approach with Paris’ equation gives the details of crack propagation process but does not take load sequence effect into account which results in a more conservative fatigue life. Thus, the modified Space-state model with consideration of threshold stress intensity factor range and fracture toughness is recommended herein to perform fatigue assessment for offshore FWTs.
Keywords: Offshore floating wind turbine, fatigue assessment, coupled aero-hydro-servo-elastic analysis, S-N curve, fracture mechanics, load sequenc
The role of residual beta-cell function on glycaemic and vascular outcomes at rest and post exercise in people with type 1 diabetes
Get PDFPhD ThesisWithin patients with type 1 diabetes (T1D), residual ꞵ-cell function and endogenous insulin secretion occurs in a substantial number of individuals. The role this ꞵ-cell function plays in glycaemic control in individuals with T1D is currently not fully understood. This is especially true around exercise, where maintaining glycaemic control is challenging and a large inter-individual variation exists. Micro amounts of endogenous insulin secretion appears to offer some protection against vascular damage and diabetes complications. Endothelial progenitor cells (EPCs) are important for the repair and growth of blood vessels, with circulating numbers increased by exercise. However, the count of EPCs appear to be reduced in individuals with T1D. It is unknown whether residual ꞵ-cell function in individuals with T1D influences these circulating cells. Therefore, this thesis aimed to investigate the effects of residual ꞵ-cell function in individuals with T1D and its influence on glycaemic control under free-living conditions and after an acute bout of aerobic exercise, as well as on the count of circulating EPCs at rest and after exercise mobilisation.
Chapter 3 demonstrated that under free-living conditions, increased endogenous insulin secretion was associated with improved continuous glucose monitoring measures, including increased time spent in euglycaemia. The results of Chapter 4 revealed that within a cohort who had comparable glycaemic control under free-living conditions, individuals with higher residual ꞵ-cell function displayed a substantially greater amount of time spent in euglycaemia in the hours following a bout of moderate intensity exercise compared to those with undetectable or lower endogenous insulin secretion. Lastly, Chapter 5 assessed the number of circulating EPCs at rest and after mobilisation with a bout of moderate intensity exercise. In comparison to matched non-diabetes controls, all markers of EPCs were lower in the T1D group, with some markers having attenuated mobilisation with exercise. Despite comparable resting counts, only the high residual ꞵ-cell function group had mobilisation of these cells with exercise within the T1D participants.
In conclusion, the findings of this thesis demonstrate that residual ꞵ-cell function impacts upon individuals with longer duration T1D. Increased C-peptide secretion is associated with improved glycaemic control under free-living conditions and after an acute bout of exercise, as well as increasing the count of circulating EPCs that are mobilised with exercise
Process intensification of biodiesel production from algae using foam flotation column
Get PDFPh. D. ThesisTo achieve cost effective biodiesel production from microalgae, the elimination of drying steps
(responsible for about 84.1 % of process energy cost) is the single most important strategy to
adopt. This project looks at combining three major components of algal biodiesel production,
namely: harvesting, oil extraction, and transesterification into a one-unit operation. The
intensified process hereby proposed, combines the advantage of three main ingredients to
achieve its aim. Cell lysing, frothing and algae cell capture by surfactants; hydrophobicity
inducement, cell lysing, as well as catalyst properties of acid; and the oil extraction and reactant
properties of methanol, were combined in the process.
The effect of operating condition (airflow), surfactant type (CTAB, MTAB, DAH, & DPC);
and concentration, and media chemistry (pH and ionic strength) on the foam flotation
harvesting of marine algae (N. oculata) was investigated. The impacts of cell properties (size,
morphology, hydrophobicity, and surface charge) were also studied. Using 20 mg L-1 CTAB,
1.2 L min-1
air flow, at pH 6, the highest enrichment ratio of 14 was achieved in 77 % of cells
recovered. When airflow and CTAB were 3.6 L min-1
and 60 mg L-1
, respectively, 83 % of
cells were recovered, albeit a low enrichment of 4. Cell properties (morphology,
hydrophobicity, and surface charge) and media chemistry (pH and ionic strength) are strong
determinants of flotation performance. The results suggest that foam flotation harvesting of N.
oculata is more collision dependent than attachment controlled and the frequency of collision
and attachment can be enhanced by reducing ionic strength as well as pH whilst increasing
airflow.
As a prerequisite for biodiesel production from algae in a flotation column, foam stability as
well as efficient methanol injection must be guaranteed. The impact of methanol and its
injection pattern on flotation process has been investigated. For foam stability to occur, the
percentage of methanol in the liquid pool must not exceed 50 % wt./wt. Using 50 % methanol
in a C. vulgaris culture, 98 % of cells (CF =18.3) were recovered via cocurrent methanol
injection foam floatation, while moisture content (water and methanol) was 156 wt. %.
Countercurrent methanol injection into the column top was achieved with the aid of methanol
distributors. This countercurrent methanol delivery system guarantees more effective and
economic methanol usage than cocurrent methanol injection, delivering methanol at 76 %
concentration.
Using the countercurrent methanol feed system in a riser-enabled column, it was possible to
convert D. salina lipids to biodiesel with yields of 9.3 ± 0.2 and 11.2 ± 0.3% after 1 and 24 h
respectively without any additional dewatering processes. Besides the novelty of this process,
it has potential for huge reduction in cost of production, due to cost savings by elimination of
drying. However, these levels of yield have to be improved on in order to ensure profitability.
To this end, it is expected that the concept demonstrated by this work will rekindle hope that
was once associated with algal biodiesel as an alternative to liquid fossil fuelsPetroleum Technology Development Fund (PTDF), SuperGen Bioenergy Hu
Pupils’ Views and Experiences of Rewards and Sanctions
Get PDFD. App. Ed. Psy. Thesis.This thesis explores the views and experiences of pupils regarding rewards
and sanctions. Current UK Government guidance recommends rewards and
sanctions as part of behaviour management systems. This appears to arise from the
behaviourist paradigm. Behavioural approaches have been questioned, suggesting
they may need further exploration. With a recent Government announcement
propounding silent corridors and sanctions, this research appears particularly
pertinent at a time when the Secretary of State for Education (February 2020) is
considering approaches to what he terms “unruly pupils and disruption”.
Chapter 1 is a systematic review of the literature pertaining to pupils’ views of
the effectiveness of rewards and sanctions. Eight journal articles were synthesised:
articles obtained pupils’ views through questionnaire-based research. The review
conclusions indicate that pupils find parental involvement and positive feedback to be
effective rewards and parental involvement and the use of authority figures to be
effective sanctions. The different individual responses suggest that a standard, single
approach may not be possible.
Chapter 3 is an empirical research project, arising from the systematic
literature review. Six pupils from two secondary schools in the Northeast of England
were interviewed about their experiences of rewards and sanctions. Interpretative
Phenomenological Analysis was used to analyse transcripts. The findings suggest
three Master Themes: relationships between teachers, pupils and parents; the
acknowledgement of differences and individuality; and the purpose, consistent and
fair application of rewards and sanctions. These findings indicate it is not what we do
but the way that we do it.
Chapter 2 links Chapters 1 and 3, reviewing my personal experiences and
philosophical stance, which underpin this work. It is hoped this thesis may contribute
to our understanding of how rewards and sanctions are experienced by pupils and
the factors pupils identify as contributing to these systems. This may have
implications for how Educational Psychologists work with schools to support pupils
and how schools implement policies to support pupil behaviour
Enabling people with dementia and mild cognitive impairment to maintain physically active lives: what role can technology play?
Get PDFPh. D. Thesis.People with dementia and mild cognitive impairment (MCI) tend to be inactive,
despite evidence that physical activity can improve cognition. To date, interventions
to support physical activity have been lacking. This thesis explores the barriers,
motivators and facilitators of physical activity for people with mild dementia and
MCI and the opportunities for digital technologies to facilitate more active lives.
In the first of three stages of human-centred design research, eight people with mild
dementia, seven with MCI and eleven of their spouses shared their experiences of
physical activity through diary-probe led interviews. Next, in design workshops with
experts in health research, engineering and design, concepts for technologies to
support physical activity were developed, informed by personas that described
participants’ experiences. Finally, storyboard illustrations of the concept
technologies were presented to participants for their critique in focus groups.
Thematic data analysis was conducted at each stage.
This thesis makes three key contributions to the literature on physical activity in MCI
and dementia. First, the importance of everyday activities for an active and fulfilled
life is revealed. Second, for people with dementia a variety of barriers to activity are
identified, including motivational impairment and difficulties performing everyday
activities, whereas MCI appears to have negligible impact. Third, the significance of
partners in an active life is revealed, particularly for those with dementia. In response
to these findings, technologies to support physical activity in dementia are
proposed, however, participants’ responses indicate that human interventions and
low-tech solutions should be prioritised. This enquiry also provides novel insights
into methods for human-centred design with people with MCI and mild dementia.
This thesis highlights the importance of working with people with dementia and MCI
to develop technologies and services that facilitate the valued, purposeful activities
that contribute to physically active and fulfilled lives
Arylation Reactions Using Diaryliodonium Salts
Get PDFPhD ThesisDiaryliodonium salts have been widely used in organic chemistry, in particular as oxidizing
agents and more recently as arylation reagents. The work presented in this thesis considers both
the metal-free and copper catalysed processes for N-, O-arylation and fluorination using
diaryliodonium salts, in particular how the control and selectivity of the transformation is
influenced by the nature of various substitution patterns and typical reaction conditions.
During this study, a range of diaryliodonium salts with different substituent patterns and
counter-ions have been synthesized in order to determine their chemical and physical properties
and the resultant selectivity of the arylation process as this variation of functionality allows
exploration of the impact of both steric and electronic factors. A novel diaryliodonium copper
complex was discovered. By using DSC-TGA analysis, the thermal decomposition of different
diaryliodonium salts has been determined. Some decompose rather than melt at these
temperatures suggesting limits on the temperatures that may be employed in their subsequent
reactions. This study has also shown that when the arylation reaction is conducted metal-free
(i.e. without a catalyst), the selectivity of fluorination and both N- and O-arylation is mostly
determined by the electronic nature of the relevant groups (the most electron-deficient arene is
transferred) whereas when the reaction was conducted in the presence of a copper catalyst, the
selectivity was mostly influenced by extreme steric factors (the least hindered arene was
transferred) although electronic control was still evident but to a lesser extent. According to
introducing a fluorous target into diaryliodonium salts and using F-SPE method, product and
by-products could be easily separated.
In summary, it was found that:
⚫ A range of diaryliodonium salts could be readily prepared using a range of synthetic
methods.
⚫ The thermal stability of diaryliodonium salts was affected by the choice of counter-ion.
⚫ When the reaction was conducted under copper catalysis good selectivity (transfer of the
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least hindered arene) could be achieved for fluorination and both N- and O-arylation
reactions
⚫ A novel diaryliodonium copper complex was discovered having a unique iodine (III)
copper interaction.
⚫ A range of fluorous diaryliodonium salts have been prepared and in association with F-SPE
enabled rapid separation of the desired arylated product from the arene by-products and
any unreacted diaryliodonium salt