Optimal scheduling of Distributed Energy Resources connected to Electricity Distribution Networks using Robust Mixed-Integer Second Order Cone Programming

Eng. D. Thesis.Tackling climate change is a global emergency, driving the electricity sector to go through rapid changes, including the increasing reliance on local generating assets, called distributed energy resources (DER). DER range from onsite energy storage systems, to gas or diesel generators, and renewable generators, but could also include other forms of generation such as electric vehicles with vehicle-to-grid capabilities. This PhD proposes a model to optimally schedule DER connected to radial distribution networks, which can form an active distribution network or a microgrid, aiming at delivering improvements in operational cost, security of supply and environmental sustainability. This is mathematically formulated using robust mixed-integer second-order cone programming. The proposed model takes into account an accurate power flow model for radial networks and a robust approach to deal with uncertainty in the market price, the electricity demand, the renewable generation, and the time and duration of a scheduled interruption from the main grid when DER form part of a microgrid. Computational experiments support the suitability of the proposed model, in a number of case studies informed by real-world data and operational scenarios. This research concludes the following. Firstly, that it is important to account for detailed modelling of network losses in operational decisions of such systems, as they profoundly affect both the cost and the network’s operating state and conditions. Secondly, that the robust approach used in this thesis in order to deal with uncertainty allows distribution system and/or microgrid operators to manage trade-offs between the level of the aforementioned uncertainties they are willing to tolerate, and the operational cost of network assets. Benefits of using the proposed model include, reduction of the operational cost, and mitigation of technical constraint violations in actual conditions. The proposed model can be used by a range of stakeholders including, microgrid operators, distribution system operators, and DER owners.Newcastle University, Engineering and Physical Sciences Research Council (EPSRC

Organising the Implementation of Industry 4.0 in a High Value German Manufacturing Firm: A Complex Adaptive Systems Approach.

Ph. D. ThesisThis thesis addresses an important research gap in empirical qualitative evidence regarding the organisational aspects of the implementation of Industry 4.0. Whereas there is a basic understanding of the technical implementation in the factory plant, the understanding of the implementation from an organisational perspective is limited. A holistic single case study with 35 semi-structured expert interviews enabled a deep exploration of an implementation in a real-world context at the firm level. The findings demonstrate how a high value German manufacturing company has implemented Industry 4.0, as well as why this firm implemented as it did. Several elements are thematically analysed, representing important examples of how manufacturing firms can organise the implementation of Industry 4.0 in praxis. Covering the three areas of actions, influences and relationships, the implications of the analysed elements are discussed in relation to six theoretical themes, namely centralisation vs. decentralisation, diffusion of new ideas, working in teams, trust, open innovation and path dependence. This thesis represents the first existing study that understands the implementation of Industry 4.0 as a Complex Adaptive System of interrelated system elements which continuously evolve over time. In this sense, a newly developed system model acknowledges important relationship characteristics that lead to a more comprehensive perspective on the complex implementation of Industry 4.0. This thesis contributes to the research field by being the first study to suggest a “dual approach” encompassing important decentralised as well as centralised implementation patterns for a successful process. It furthermore demonstrates how workforce concerns regarding job security significantly influence the emergence of system elements regarding change management during the implementation of Industry 4.0. The thesis offers academic contributions to the Industry 4.0 implementation literature, as well as organisational elements recommended for practitioners when organising the implementation of Industry 4.0

Co- and Post-seismic Deformation of the 1999 Chi-Chi Earthquake Revealed by Earth Observations

Ph. D. ThesisThe Mw 7.6 Chi-Chi earthquake struck Central Western Taiwan in 1999. The rupture was complex with several dislocations along the 100-km long Chelungpu thrust fault. Revisiting this earthquake is a challenge, as the precision and coverage of the Earth observations available are quite poor, but it allows better understanding of regional fault properties. Furthermore, the topographic and vegetation coverage complexity of the area prevents coherent radar images. In this thesis, radar and optical images, and terrestrial geodetic measurements, were utilised to study the Chelungpu fault and more specifically the impact of the Chi-Chi earthquake. First, five types of Earth observations were processed to investigate the co-seismic deformation. The Particle Swarm Optimization and Okada Inversion (PSOKINV) geodetic inversion package was used with the generalized Akaike’s Bayesian Information Criterion (gABIC) to precisely determine the coseismic slip distribution and relative weighting of datasets. Differences in results using the data sets jointly or separately (e.g., under-estimation due to InSAR, inconsistencies in SPOT offsets, smoother slip distribution with gABIC weighting) are observable. Most of the energy was released in the northern part of the fault, where the strike veers toward the east, and mainly at depths of less than 4 km. The PSOKINV-gABIC approach is viable for the study of complicated cases such as the Chi-Chi earthquake (complex fault geometry and multi-source observations) and can substantially benefit the weight determination and physical (no overlap or gap) realism of the fault geometry. Second, the post-seismic deformation of this event was observed using 20 years of time series from InSAR and GPS. Then, a model of the afterslip and viscoelastic relaxation was built. 11 years of ERS, 3 years of EnviSAT, 6 years of Sentinel-1A/B descending and 3 years of Sentinel-1A/B ascending images were processed using GAMMA-Remote Sensing software and atmospherically corrected using GACOS (Generic Atmospheric Correction Online Service for InSAR). Finally, InSAR time series were extracted and validated using GPS data. The modelling of the postseismic deformation following the Chi-Chi earthquake was done using a power-law Burgers rheology to analyse the interplay between afterslip and viscoelastic flow. From the time series, a change in the ground displacement can be observed in 2004 showing a slow-down of afterslip deformation. The forward modelling of the postseismic deformation showed that the maximum afterslip is observed on the southern part of the fault, on the decollement in depth (while the maximum slip was happening at shallow depth on the north section of the fault during the co-seismic deformation). Furthermore, the study of the strain enabled me to conclude that the interseismic phase has started over most of the area, most segments of the Chelungpu fault are now getting locked again. More data coverage and a longer monitoring of the Chelungpu fault will be needed to observe the entire earthquake cycleESA, UK NER

Simulating and visualising the hydrological and landscape impacts of reservoir engineering at Crummock Water, England

Eng. D. ThesisThe Earth’s 57,000 large water reservoirs have significant impacts on hydrology and landscapes. Meanwhile, environmental degradation is destabilising the climate, ecosystems, and hydrological functionality. In Europe and North America, landscape-scale environmental management schemes are being proposed, including reservoir decommissioning to rehabilitate river catchments. Yet, some proposed schemes have failed due to poor stakeholder engagement and shifting environmental baselines. This research has developed novel approachesto address these issues. It has applied these to Crummock Water raised lake in England, where United Utilities and the Environment Agency are investigating the feasibility of removing infrastructure to renaturalise the lake and the River Cocker. The hydrological impacts of anthropogenic modifications in Crummock Water’s catchment were assessed using existing data, expanded hydrometric monitoring, hydrological modelling, and archival research. Circa 1880, Crummock Water’s outlet was excavated and two timber weirs installed to control outflows. In 1903, the extant masonry weir was built, raising the lake level ~0.6 m. Abstraction reduces lake levels, which necessitates sluice operations to maintain outflows during dry periods, causing further drawdown. Hydrological models of reservoircontaining catchments should include reservoir processes. SHETRAN 4.5 (‘Reservoir’)software was developed to integrate reservoir structures and operations into a physically-based, spatially-distributed hydrology model. A SHETRAN-Reservoir model of the Crummock Water catchment substantially outperformed a SHETRAN-Standard model, particularly during and after dry periods. Several reservoir decommissioning scenarios were constructed. Simulations indicate that decommissioning would ameliorate drawdown of Crummock Water and make the River Cocker’s flow regime more dynamic. The simulated landscape impacts of reservoir engineering at Crummock Water were shown in the context of long-term catchment evolution using 4D landscape visualisation. The catchment’s evolution was conceptualised, before being digitally reconstructed and rendered using GeoVisionary software. The resulting 4D landscape model spanned 14,000 years, from the last Ice Age to (simulated) renaturalisation scenarios in 2030. The effects of 4D landscape visualisation on stakeholder attitudes were investigated, using surveys and workshops with 45 participants in two treatments (‘long’ and ‘short’ visualisation). It was hypothesised that ii presenting extended landscape evolution information would change (H1) stakeholder beliefs around catchment naturalness, and (H2) attitudes towards reservoir renaturalisation. Results showed that the workshops changed both beliefs and attitudes towards renaturalisation. Furthermore, the extended evolution information had a statistically significant effect on attitudes (H2), but not on beliefs (H1). This EngD has developed tools to support decision-making in reservoir engineering and landscape-scale environmental projects: firstly, hydrological and landscape models to show the impacts of reservoir decommissioning at Crummock Water; secondly, a generic freelyavailable physically-based, spatially-distributed modelling package for simulating the hydrological impacts of reservoir operations; thirdly, a new approach to visualising simulated hydrological changes, such as lake levels, and landscape evolution in 4D, and; fourthly, an approach to visualising proposed environmental management schemes in the context of longterm landscape evolution, to reset shifting environmental baselines. Finally, the research findings have been synthesised into a landscape visualisation development framework to support enhanced stakeholder engagement in future landscape-scale projects.Engineering and Physical Science Research Council (EPSRC) and United Utilities pl

Examining the production and perceptions of public space in developing urban environment: an exploration of Ho Chi Minh City, Vietnam

Ph. D. ThesisIn developing countries, there is a growing trend for improving public space which transforms the built environment as well as raises the requirement for better public life. The driving forces to enhance experienced quality of urban spaces play significant role in urban design process. Moreover, according to the new life style and social contexts of market demanding, the current political systems and design styles have to be shifted and adapted so that the quality of these planning can meet the need of local citizens. Additionally, in the light of encouraging human interaction with urban environment, the design for public space raises the awareness of both public and private developers as well as local authorities and professionals in planning. The role of each of stakeholders during planning process may give the opportunities for these spaces to have an attractive appearance, exciting activities, and successful formulated design as well as involving all people. The study takes place around the feature of walkable streets as public spaces which associated to the discovered and investigation of two pedestrian streets in Ho Chi Minh City, Vietnam. This research contributes to the discussion that investigates the nature of planning and control in decision making process in the Southeast Asian’s socialism country. Furthermore, the study tends to explore social influences involving within the management of local authorities, the meaning of places and people’ perceptions on these public spaces. By using the combination of qualitative, quantitative and case study approaches, the research tends to answer how the triad (local authorities, planning professionals, and developers) deals with design planning for public spaces, the perceived of public space and the perception of users while these public spaces are being transformed. The result of this study not only contributes to the fields of urban design in Vietnam (which is very new in this country), but also it raises the awareness to the design for public space through the lens of all stakeholders involve in these places in the context of Southeast Asian cultures and different management system

Vitamin D status and biomarkers of functional health and ageing in very-old adults : analysis of the Newcastle 85+ study

PhD ThesisThe number of those aged over 80 years-old (the “very-old”) will increase from 5% of the population in European countries in 2010, to more than 10% of the population by 2050 (OECD, 2013). Very little is known about the nutritional intake, nutritional status and its association with health and wellbeing in the very-old. Due to its diverse biological effects, vitamin D has gained immense interest recently as a potential modifier for a range of health outcomes This PhD systematically reviewed the available literature to provide an accurate snapshot of vitamin D status in the very-old. It also used a unique dataset from the Newcastle 85+ Study, a longitudinal community-dwelling study of health trajectory and outcomes conducted in over 800 people from the North-East of England aged 85 years. The overall aim of using this data were to explore vitamin D association with a range of functional and ageing biomarkers in the very-old. Vitamin D status [25(OH)D] was available for 775 participants, and measured by immunoassays at baseline only and divided to the following concentration: 50 nmol/l (high). Disability was measured using a questionnaire on the difficulty of performing 17 Activities of Daily Living at baseline, 1.5, 3 and 5 years. NTproBNP was measured using an electrochemiluminescent sandwich immunoassay. The HbA1c was measured using a Tosoh Eurogenetics automated HLC-723G7 HPLC analyser. Telomere Length was measured as an abundance of telomeric template vs. a single gene by quantitative real-time PCR. Spirometry and peak flow measurements were to obtain three technically satisfactory maximal effort ‘blows’ to generate reproducible FEV1and FVC. Results of the systematic review showed that prevalence of deficiency varies by latitude and living conditions of the participants, and that vitamin D deficiency is widespread in many regions, particularly in Europe. Using the Newcastle 85+ Study data also showed a high prevalence of vitamin D deficiency (>30%) was found amongst very-old adults. Findings of this thesis indicate that participants with low 25(OH)D concentration (<25 nmol/l) were more likely to have a poorer disability trajectory over 5 years compared with those with moderate concentration (25–50 nmol/l) (OR= 3.12, 95% CI= 1.6–5.8, p= 0.001), although physical activity was the strongest predictor of disability trajectories. However, this thesis could not prove the protective effect of vitamin D in regards to metabolic and cardiopulmonary health biomarkers (NT-proBNP, HbA1c, FEV1, FVC and diastolic blood pressure) in fully adjusted models at baseline or over 18 and 36 months. Finally, high 25(OH)D concentration is positively associated with Telomere Length (95%CI= 12.0-110.3, B= 61.2+25.0, p=0.015) but does not have protective effects over 18 and 36 months. In conclusion, this thesis highlights that vitamin D deficiency is very common in very-old adults and that low vitamin D status is associated with at least some functional and ageing biomarkers in this under studied age group.Saudi Arabian Government and to Umm Al Qura Universit

Multiscale modelling and structure-guided development of small molecules tackling neuroinflammation and inflammageing

Ph. D. ThesisEarly diagnosis and treatment of neurodegenerative diseases has gained attention, given their increasing prevalence. Multiple proteins are currently being investigated as novel targets for drug development, including α7 nicotinic receptors and mitochondrial translocator protein TSPO. These proteins play an important role in neuroinflammation, which makes them attractive for development of drugs and diagnostics. However, small molecule development has been hampered by existence of a human-specific dupa7 isoform, and an A147T-TSPO polymorph, which present a challenge for development of potent and selective ligands. In this work, I characterised the structure and dynamics of the most plausible functional a7 pentamers bearing dupα7 subunits. The receptors have been modelled and assessed using multiscale molecular dynamics (MD) simulations and enhanced sampling techniques. The energy landscapes of the pentamers with different stoichiometries showed that receptors with a low ratio of dupα7/α7 remained functional. Sensitivity of dupa7 receptors to an antagonist (α- BTX) and amyloid Aβ42 has also been assessed. Further, putative “druggable” binding sites at dupα7 receptors were mapped, and interactions between dupα7 and small molecules were explored using a combination of solvent mapping, MD simulations, and molecular docking. Results indicated that neither established orthosteric agonist nor allosteric ligands can bind to dupα7/dupα7 interfaces, however, α7/dupα7 interfaces remain “druggable”. In addition, several novel allosteric sites were detected on α7/dupα7 receptors. The final part of this work focused on development of novel tracers for A147T-TSPO variant. Using a combination of molecular modelling, MD simulations, and structure-guided drug design, I have evaluated plausible binding modes of established TSPO ligands to A147TTSPO. Results explain the origins of diminished affinity of some established TSPO ligands to A147T-TSPO. Moreover, I have identified the position of fluorine atom, which is a derivative of DPA-714 compound to bind to A147T-TSPO with sub-nanomolar affinity. The compound, denoted as MKD, is feasible for the radiosynthesis

New insights on SepL, the gatekeeper component in Type 3 secretion system of enteropathogenic E. coli, though functional interchangeability studies

PhD ThesisThe pathogenesis of many gram-negative bacteria depends on Type Three secretion systems (T3SSs) that deliver subversive effector proteins into the infected host cell. These injectosomes evolved from flagellar export apparatus with significant homology remaining between components that form the T3SS/flagella export channel (which spans the bacterial envelope) and the sorting platform that controls the timing and hierarchy of substrate export. There are distinct T3SS families where high protein homology is a feature within, but not between families. One family is represented by the enteropathogenic E. coli (EPEC) T3SS encoded-alongside genes for T3SS substrates (several T3SS components; translocators (link T3SS to host cell); effectors, chaperones (aid stability/export of T3SS substrates), regulators, and intimin surface protein-on a 41-gene region called LEE (Locus of Enterocyte Effacement). Unexpectedly, LEE was found in an Edwardsiella tarda (E. tarda) strain with genetic rearrangement linked to gene loss and disruption. However, recent studies support functionality with the discovery of unprecedented divergence indicative of a district T3SS family. Preliminary functional interchangeability studies identified E. tarda T3SS proteins that could and, more interestingly, could not functionally substitute their EPEC counterparts. The divergence level did not predict functionality. Studies with support complementation defects for five E. tarda T3SS proteins are described here, which revealed unexpectedly novel functions for SepL (the gatekeeper controlling switching from translocator to effector substrates). Further investigation revealed that i) SepL, 3 (CesT, CesAB, CesD2), an effector (EspF), and two T3SS components (EscC, EscD) each control the cellular O127-antigen level; ii) SepL protects Tir from cleavage; and iii) SepL, CesT, CesAB, and CesD2 protect EspF from cleavage. Cleavage event requires EscU; the latter has auto-proteolytic activity linked to regulating substrate export hierarchy. Importantly, these activities were not shared by the E. tarda homologs with domain swap experiments linking different SepL functionalities to one or more of its three X-bundling domains.Taibah University and the Saudi Arabian Cultural Bureau (SACB

Graphene resonators for mass sensing applications

PhD ThesisGraphene’s exceptional physical and mechanical properties make it an excellent nanomaterial for MEMS/NEMS devices with wide reaching applications. This thesis explores graphene as a nanomaterial, its use in mass sensing applications and the suitability of existing theoretical models to describe its behaviour as a rectangular resonator. Several local and nonlocal continuum models have been proposed in literature for the vibration analysis of graphene resonators. But with very little experimental data to validate these theoretical models, most of the solutions employed to solve these models compare their results with results from other theoretical models, leading to doubts about their validity and accuracy. In addition to providing a guide for determining the suitable theoretical model for different sized rectangular graphene resonators, this work establishes that a small-scale parameter 0 of any value between 0 and 2 needs to be incorporated in any local continuum modelled applied to micro-sized graphene sheets to avoid overestimation of the frequency of the sheets. A fabrication route for NEMS and MEMS devices with rectangular graphene resonators up to 32 by 7 is also developed with the provision for magnetomotive actuation via Lorentz force with possible capacitive readout capabilities. This is important as the use of graphene in MEMS/NEMS is being hurriedly transitioned from the Research space to the marketplace

A flat extension theorem for truncated matrix-valued multisequences

PhD ThesisGiven a truncated multisequence of p × p Hermitian matrices S := (Sγ1,...,γd ) (γ1,...,γd)∈Nd 0 0≤γ1+···+γd≤m , the truncated matrix-valued moment problem on R d asks whether or not there exists a p×p positive semidefinite matrix-valued measure T, with convergent moments of all orders, such that Sγ1,...,γd = Z · · · Z Rd x γ1 1 · · · x γd d dT(x1, . . . , xd) for all (γ1, . . . , γd) ∈ N d 0 which satisfy 0 ≤ Pd j=1 γj ≤ m. When such a measure exists we say that T is a representing measure for S. We shall see that if m is even, then S has a minimal representing measure (that is, Pκ a=1 rank Qa is as small as possible) if and only if a block matrix determined entirely by S has a rank-preserving positive extension. In this case, the support of the representing measure has a connection with zeros (suitably interpreted) of a system of matrix-valued polynomials which describe the rank-preserving extension. The proof of this result relies on operator theory and certain results for ideals of multivariate matrix-valued polynomials. Our result subsumes the celebrated flat extension theorem of Curto and Fialkow. We shall pay particularly close attention to the bivariate quadratic matrix-valued moment problem (that is, where d = 2 and m = 2)