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A methodology for the quantitative evaluation of attacks and mitigations in IoT systems
Get PDFPhD ThesisAs we move towards a more distributed and unsupervised internet, namely through the
Internet of Things (IoT), the avenues of attack multiply. To compound these issues, whilst
attacks are developing, the current security of devices is much lower than for traditional
systems.
In this thesis I propose a new methodology for white box behaviour intrusion detection
in constrained systems. I leverage the characteristics of these types of systems, namely their:
heterogeneity, distributed nature, and constrained capabilities; to devise a pipeline, that given
a specification of a IoT scenario can generate an actionable intrusion detection system to
protect it.
I identify key IoT scenarios for which more traditional black box approaches would
not suffice, and devise means to bypass these limitations. The contributions include; 1) A
survey of intrusion detection for IoT; 2) A modelling technique to observe interactions in IoT
deployments; 3) A modelling approach that focuses on the observation of specific attacks
on possible configurations of IoT devices; Combining these components: a specification
of the system as per contribution 1 and a attack specification as per contribution 2, we can
deploy a bespoke behaviour based IDS for the specified system. This one of a kind approach
allows for the quick and efficient generation of attack detection from the onset, positioning
this approach as particularly suitable to dynamic and constrained IoT environments
Scaling the development of large ontologies : identitas and hypernormalization
Get PDFPhD ThesisDuring the last decade ontologies have become a fundamental part of the life sciences
to build organised computational knowledge. Currently, there are more than
800 biomedical ontologies hosted by the NCBO BioPortal repository. However, the
proliferation of ontologies in the biomedical and biological domains has highlighted
a number of problems. As ontologies become large, their development and maintenance
becomes more challenging and time-consuming. Therefore, the scalability of
ontology development has become problematic. In this thesis, we examine two new
approaches that can help address this challenge.
First, we consider a new approach to identi ers that could signi cantly facilitate the
scalability of ontologies and overcome some related issues with monotonic, numeric
identi ers while remaining semantics-free. Our solutions are described, along with
the Identitas library, which allows concurrent development, pronounceability and
error checking. The library integrated into two ontology development environments,
Prot eg e and Tawny-OWL. This thesis also discusses the ways in which current ontological
practices could be migrated towards the use of this scheme.
Second, we investigate the usage of the hypernormalisation, patternisation and programatic
approaches by asking how we could use this approach to rebuild the Gene
Ontology (GO). The aim of the hypernormalisation and patternisation techniques
is to allow the ontology developer to manage its maintainability and evolution. To
apply this approach we had to analyse the ontology structure, starting with the
Molecular Function Ontology (MFO). The MFO is formed from several large and
tangled hierarchies of classes, each of which describe a broad molecular activity.
The exploitation of the hypernormalisation approach resulted in the creation of a
hypernormalised form of the Transporter Activity (TA) and Catalytic Activity (CA)
hierarchies, together they constitute 78% of all classes in MFO. The hypernormalised
structure of the TA and CA are generated based on developed higher-level patterns
and novel content-speci c patterns, and exploit ontology logical reasoners. The gen-
erated ontologies are robust, easy to maintain and can be developed and extended
freely. Although, there are a variety of ontologies development tools, Tawny-OWL is
a programmatic interactive tool for ontology creation and management and provides
a set of patterns that explicitly support the creation of a hypernormalised ontology.
Finally, the investigation of the hypernormalisation highlighted inconsistent classi-
cations and identi cation of signi cant semantic mismatch between GO and the
Chemical Entities of Biological Interest (ChEBI). Although both ontologies describe
the same real entities, GO often refers to the form most common in biology, while
ChEBI is more speci c and precise. The use of hypernormalisation forces us to
deal with this mismatch, we used the equivalence axioms created by the GO-Plus
ontology.
To sum up, to address the scalability and ease development of ontologies we propose a
new identi er scheme and investigate the use of the hypernormalisation methodology.
Together, the Identitas and the hypernormalisation technique should enable the
construction of large-scale ontologies in the future.Northern Borders University, Saudi Arabia
The Evolution of Early Christian Theology of Martyrdom in the Pre-Decian Period: Collective Memory and Martyrological Interpretation of the New Testament in Polycarp, Lyon, and Perpetua
Get PDFPh. D. Thesis.While early Christian martyrdom accounts had a profound impact on the formation, and
success, of the primitive Church, it appears that before 250, the persecutions of Christians were
‘local and sporadic’ (Barnes, 1968). Historical approaches failed to explain these disparities
between Christian and pagan sources and to answer questions such as ‘what is martyrdom?’,
‘what are the origins of martyrdom?’ and ‘why were the early Christians persecuted?’. As a
result, recent studies have been focusing on more theoretical approaches. Following this trend,
this thesis explores the origins of early Christian theology of martyrdom as a discursive creation
forged in the collective memory of the first martyrdom accounts as well as in the martyrological
interpretation of both New Testament texts and pagan narratives such as Socrates’s death. The
first two chapters of the thesis are mostly introductory, the first chapter presenting an overview
of the debates and challenges surrounding the study of early Christian martyrdom, and the
second covering the methodological approach adopted in this thesis, namely discourse analysis
and the collective memory theory. The following three chapters examine three early martyrdom
accounts (the Martyrdom of Polycarp, the Martyrs of Lyon and the Passion of Perpetua and
Felicity) in order to both highlight the different influences/discourses in the texts and reveal the
evolution of the theology of martyrdom. In each case study, both Christian and pagan sources
are scrutinised for the rudiments of a concept of martyrdom and its discourse, focusing on
possible expressions of collective memory within these martyrdom accounts. This thesis thus
contends that the martyrological interpretation of NT texts (Revelation in particular), and
assimilation of these interpretations into the communities’ collective memory, provided an
eschatological platform in which early Christian authors could inscribe their own experiences,
shaping their reality, their narratives and ultimately, their identity
Determining the efficacy of a usage-based language intervention in the early years : a non-randomised pilot stud
Get PDFPhD ThesisIntroduction Language skills are crucial for positive social, emotional, academic and economic
outcomes across the lifespan. Whilst most children acquire language relatively easily, a number of
children experience difficulties. Early intervention can mitigate the risks associated with poor
language skills, and the importance of evidence-based intervention is widely recognised by Speech
and Language Therapists. Despite this, there are few robustly evaluated language interventions for
young children.
Building Early Sentences Therapy (BEST) is a complex language intervention designed to support
children to understand and produce two, three and four clause-element sentences (McKean et al.,
2013).
This thesis presents a non-randomised quasi-experimental study of BEST with sign, BEST without sign
and Treatment as Usual with four key goals: 1) to evaluate the efficacy of BEST, 2) to assess the use
of sign as an ‘active ingredient’, 3) determine the effect sizes from goals 1 and 2, and 4) to inform
further evaluation.
Methods Schools were assigned to three treatment arms matched with respect to classroom oral
language environment and socioeconomic status. Participants were 3;5-4;5-year-old children with
expressive, receptive or mixed language difficulties below the 16th centile.
The intervention was 16 sessions of BEST with or BEST without sign. The TAU group received their
usual classroom provision.
Children’s outcomes on production, comprehension, content and morphology on targeted and non targeted language structures were measured.
Results Visual trends showed improvement for children receiving BEST.
There was evidence for the efficacy of BEST compared to TAU for Production, Content and
Morphology outcomes.
There was also evidence that BEST with Sign improved outcomes further for Production and
Sentence Morphology outcomes.
Content Analysis of teacher feedback led to the generation of recommendations for future studies
evaluating BEST.
Discussion Children receiving BEST make progress with production, content and morphology
outcomes. The role of sign in further supporting progress is positively indicated. A further trial of
BEST is warranted
Using Ipsative assessment to improve feedback quality and the student assessment experience in university computer science
Get PDFPhD ThesisAssessment and feedback are important aspects of Higher Education used to provide
certification to students and to facilitate learning. Therefore, both practices are important to get
right. Despite their significance, the results of the National Student Survey show that
assessment and feedback are the biggest sources of dissatisfaction for UK undergraduate
students (Ferrell, 2012).
This thesis outlines a study that set out to understand the issues faced by undergraduate
students’ in their experience of assessment and feedback, and whether the adoption of an
Ipsative assessment approach could help to ameliorate these issues. Ipsative assessment focuses
on the students’ improvement from the previous assessment and their personal best as opposed
to the meeting of external criteria. The focus of Ipsative assessment is placed on the students
learning gain and the distance travelled, not on the ability to meet certain assessment criteria
(Hughes, 2011; Hughes et al, 2014).
This research tracked three cohorts of undergraduate students taking their first Computer
Science module in programming at Newcastle University. Case study 1 set out to understand
students’ perceptions of issues within their assessment and feedback experience. Data were
collected from student focus groups, interviews and questionnaires. Case study two analysed
historical online feedback given to previous cohorts on the module CSC1021, programming 1,
during the academic years 2012/2013 to 2016/2017. In total, 942 items of feedback were
analysed to determine if the perceived issues were consistently present in the feedback given to
students. Finally, to investigate the potential impacts of Ipsative assessment, a system called
‘Computing: Ipsative Assessment' was trialled with first-year students.
Three main issues were identified to contribute to student dissatisfaction, (i) a lack of
assessment literacy, (ii) the mark-driven nature of students and (iii) a mismatch of expectations
between staff and students regarding feedback. By encouraging the use of self-reflection and
self-guided learning through Ipsative Assessment, these issues could be mitigated
Diversity and biogeography of Hadal Amphipoda
No full textPh. D. Thesis.he ocean’s deepest ecosystem, the hadal zone (> 6000 m), is comprised of 47 subduction trenches, non-subduction troughs, and trench faults. These geomorphologically-complex features have been considered to function as ecological and evolutionary independent units, because of extreme environmental conditions, long-term geographical isolation, and evolutionary selection pressures. The order Amphipoda has emerged as a model taxon for understanding the evolution of life and ecology in the hadal zone. Much progress has been made identifying the diversity and understanding the ecology within individual features. This work, however, has solely focused on deep, subduction trenches around the Pacific Rim, leaving shallower features and non-Pacific features underrepresented.
This thesis aims to improve our understanding of the drivers of diversity and population and community structure among scavenging amphipods across the hadal zone. This body of work is executed through three lines of study, utilizing a specimen collection from 16 hadal features. The first line applied an integrative taxonomic approach to expand the known diversity of scavenging amphipods in the Indian and Pacific Oceans. This work has resulted in the description of Eurythenes plasticus, the world’s first new species described to be impacted by microplastics, Eurythenes atacamensis, a unique hadal dominate lineage in the Peru-Chile Trench, Stephonyx sigmacrus, the deepest known species of this genus, and Civifractura serendipia, a new cryptic genus and species within the Alicellidae family. The second line assessed how the community shifts across the abyssal-hadal transition zone in a non-subduction hadal feature, the Wallaby-Zenith Fracture Zone, Indian Ocean. The third line investigated the global distribution and phylogeography of Bathycallisoma schellenbergi between twelve hadal features in four oceans. Together, this thesis expands our knowledge of hadal communities to features beyond subduction trenches and contributes to the disentanglement of the environmental, tectonic, and other drivers of contemporary diversity across the hadal zone
Mitochondrial dysfunction in the pathogenesis of osteoporosis
Get PDFPh. D. Thesis.Osteoporosis is a skeletal disease, characterised by reduced bone mass and altered
microarchitecture, with subsequent loss of strength, increased fragility and risk of fragility fractures.
Hip fractures alone cost the NHS £2 billion per year and have associated high morbidity and
mortality. The pathogenesis of falling bone mineral density, ultimately leading to a diagnosis of
osteoporosis is incompletely understood but the disease is currently thought to be multifactorial.
Humans are known to accumulate mitochondrial mutations with age and mounting evidence
suggests that this may be intrinsic to changes in phenotype with advancing age and pathogenesis of
age-related disease. Mitochondrial mutations have been shown to occur from the age of 30 years in
tissues such as colon, which interestingly correlates with commencement of decline in bone mineral
density.
This work has demonstrated the presence of mitochondrial DNA mutations in individual human stem
cells and respiratory chain deficiency in human osteoblasts for the first time using novel techniques
including single-cell PCR, flow cytometry and imaging mass cytometry.
Work with the Polgmut/mut mouse model which acquire mitochondrial mutations at an enhanced rate,
has demonstrated significantly higher levels of osteoblast respiratory chain deficiency compared to
age matched wild type controls. This was associated with significantly reduced osteoblast population
densities, reduced bone formation and increased osteoclast activity.
Through these novel techniques, this work has demonstrated that underlying mitochondrial
pathology directly affects mesenchymal stem cells and osteoblast potentially contributing to
osteoporosis which will lead the way for development of new treatment modalities
Low-grade Heat Recovery for Sustainable Automotive Manufacturing
Get PDFPhD ThesisIn response to the need for UK manufacturing to decarbonise its production processes and become
more sustainable, an increasing interest has been given to low-grade heat recovery technologies able
to energy-efficiently control the temperature and humidity of the air supplied for product-specific
applications. This study aims to investigate the novel use of liquid desiccant technology in automotive
painting. The work includes a literature review on automotive manufacturing and painting to analyse
processes, energy consumption, waste heat sources and the importance of temperature and humidity
control, identifying how the liquid desiccant technology could match these conditions. Based on the
knowledge of the main operating factors of the liquid desiccant technology, a framework for the
techno-economic feasibility analysis of different heat recovery scenarios was developed. The techno economic analysis proposed new correlations for the analysis of the heat and mass transfer in the
dehumidifier and regenerator of the liquid desiccant system able to predict the performance of the
system under different conditions. Novel configurations for the use of liquid desiccant technology in
the field of low-grade heat recovery and painting processes were designed and case studies were
carried out to estimate the energy and economic performance of the designed novel configurations.
Also, the performance of the technology in different outdoor air conditions, such as hot and humid
climates, was estimated and compared with the UK.
The case studies showed that the potential for heat recovery from transformers, compressors and
thermal oxidisers and its use for air-conditioning, painting operation and air dehydration are high
enough to achieve significant energy savings in terms of natural gas and electricity. Also, significant
energy savings for cooling and dehumidification are achievable by employing the technology in hot
and humid climates. Potential innovative solutions to increase the energy and economic performance
of the liquid desiccant technology for automotive painting were also recommended. It was concluded
that energy-efficient use of low-grade heat sources to drive the liquid desiccant technology could help
the automotive industry to reduce its energy consumption and increase the sustainability of its
production process
Investigation of the zinc-ZIP8-MTF1 signalling pathway in human OA chondrocytes
Get PDFPhD ThesisOsteoarthritis (OA) is a common musculoskeletal disease characterised by articular cartilage loss resulting in severe joint pain, chronic morbidity, and premature mortality. There are no licensed OA drugs and current treatments involve pain relief with analgesics and joint replacement surgery.
In murine cartilage chondrocytes the zinc-ZIP8-MTF1 signalling pathway causes cartilage breakdown. Pathway activation by interleukin-1β (IL-1β) stimulates upregulation of zinc transporter gene Slc39a8 (coding for ZIP8), increased intracellular zinc levels, nuclear translocation of the zinc-dependent MTF1 transcription factor and upregulation of genes encoding cartilage matrix-degrading proteins including Mmp13 and Adam-ts5.
This thesis aimed to investigate if the IL-1-mediated zinc-ZIP8-MTF1 pathway is active in human chondrocytes and if this pathway contributes to OA pathogenesis.
Analysis of OA-related transcriptomic datasets revealed that SLC39A14 but not SLC39A8, was dysregulated in human OA cartilage and mouse OA models. Human articular chondrocytes (HACs), and the chondrocyte cell lines SW1353 and T/C-28a2, were cultured in monolayer and treated with IL-1α and/or ZnCl2 or IL-1β. Genes involved in inflammation, zinc homeostasis and cartilage degradation were measured by quantitative PCR. MTF1 activity and subcellular localisation were evaluated using luciferase reporter assays, immunocytochemistry (ICC) and western blots.
SLC39A8 and SLC39A14 were upregulated in IL-1α-treated HACs 5.5 and 2.9-fold respectively but were selectively elevated in SW1353 (SLC39A8, p <0.0001) and T/C-28a2 cells (SLC39A14, p = 0.0001). IL-1 raised intracellular zinc ion levels in HACs (p=0.0004) but not in the cell lines. IL-1 upregulated MMP13 in T/C-28a2 lines and SW1353 cells, while both MMP13 and ADAM-TS5 were upregulated in T/C-28a2 cells. MMP13 and ADAM-TS5 expression was non-significant after IL-1 treatment in HACs. IL-1 repressed MTF1 transactivation activity in SW1353 cells (14.5%, p=0.0114), even when MTF1 itself was overexpressed (17.2% p<0.0001). Western blotting and ICC results were non-correlative.
Zinc-ZIP8-MTF1-mediated cartilage matrix-degrading gene upregulation induced through IL-1α as a contributing factor to human OA pathogenesis was inconclusive
Multi-layer carbon fiber reinforced plastic characterization and reconstruction using eddy current pulsed thermography
Get PDFPh. D. Thesis.Carbon fibre composite materials are widely used in high-value, high-profit
applications, such as aerospace manufacturing and shipbuilding – due to their low
density, high mechanical strength, and flexibility. Existing NDT techniques such as
eddy current testing suffers from electrical anisotropy in CFRP (carbon fibre reinforced
plastics). Ultrasonic is limited by substantial attenuation of signal caused by the multilayer structure. The eddy current pulsed thermography has previously been applied for
composites NDE (non-destructive evaluation)such as impact damage, which has the
ability for quick and accurate QNDE(quantitative non-destructive evaluation)
inspection but can be challenging for detection and evaluation of sub-surface defects,
e.g., delamination and debonding in multiple layer structures. Developing QNDE
solutions using eddy current thermography for addressing subsurface defects evaluation
in multi-layer and anisotropic CFRP is urgently required.
This thesis proposes the application of eddy current pulsed thermography (ECPT) and
ECPuCT (eddy current pulse compression thermography) for tackling the challenges of
anisotropic properties and the multi-layer structure of CFRP using feature-based and
reconstruction-based QNDE and material characterisation. The major merit for eddy
current heating CFRP is the volumetric heating nature enabling subsurface defect
detectability. Therefore, the thesis proposes the investigation of different ECPT and
their features for QNDE of various defects, including delamination and debonding.
Based on the proposed systems and QNDE approach, three case studies are
implemented for delamination QNDE, debonding QNDE, conductivity estimation and
orientation inverse reconstruction using the two different ECPT systems and features,
e.g., a pulse compression approach to increase the capability of the current ECPT
system, the feature-based QNDE approach for defect detection and quantification,
and reconstruction-based approach for conductivity estimation and inversion. The
three case studies include 1) investigation of delamination with different depths in terms
of delamination location, and depth quantification using K-PCA, proposed temporal
feature-crossing point feature and ECPuCT system; 2) investigation of debonding with
different electrical and thermal properties in terms of non-uniform heating pattern
removal and properties QNDE using PLS approaches, impulse response based feature