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The highly efficient ultra-low-power management unit is essential in powering low-power wearable electronics. Such devices are powered by a single input source, either by a battery or with the help of a renewable energy source. Thus, there is a demand for an energy conversion unit, in this case, a DC-DC converter, which can perform either step-up or step-down conversions to provide the required voltage at the load. Energy scavenging with a boost converter is an intriguing choice since it removes the necessity of bulky batteries and considerably extends the battery life. Wearable devices are typically powered by a monolithic battery. The commonly available battery such as Alkaline or Lithium-ion, degrade over time due to their life spans as it is limited by the number of charge cycles- which depend highly on the environmental and loading condition. Thus, once it reaches the maximum number of life cycles, the battery needs to be replaced. The operation of the wearable devices is limited by usable duration, which depends on the energy density of the battery. Once the stored energy is depleted, the operation of wearable devices is also affected, and hence it needs to be recharged. The energy harvesters- which gather the available energy from the surroundings, however, have no limitation on operating life. The application can become battery-less given that harvestable energy is sufficiently powering the low-power devices. Although the energy harvester may not completely replace the battery source, it ensures the maximum duration of use and assists to become autonomous and self-sustain devices. The photovoltaic (PV) cell is a promising candidate as a hypothetical input supply source among the energy harvesters due to its smaller area and high power density over other harvesters. Solar energy use PV harvester can convert ambient light energy into electrical energy and keep it in the storage device. The harvested output of PV cannot directly connect to wearable loads for two main reasons. Depending on the incoming light, the harvested current result in varying open-circuit voltage. It requires the power management circuit to deal with unregulated input variation. Second, depending on the PV cell's material type and an effective area, the I-V characteristic's performance varies, resulting in a variation of the output power. There are several works of maximum power point tracking (MPPT) methods that allow the solar energy harvester to achieve optimal harvested power. Therefore, the harvested power depends on the size and usually small area cell is sufficient for micro-watt loads low-powered applications. The available harvested voltage, however, is generally very low-voltage range between 0.4-0.6 V. The voltage ratings of electronics in standard wearable applications operate in 1.8-3 V voltages as described in introduction's application example section. It is higher than the supply source can offer. The overcome the mismatch voltage between source and supply circuit, a DC-DC boost converter is necessary. The switch-mode converters are favoured over the linear converters due to their highly efficient and small area overhead. The inductive converter in the switch-mode converter is common due to its high-efficiency performance. However, the integration of the inductor in the miniaturised integrated on-chip design tends to be bulky. Therefore, the switched-capacitor approach DC-DC converters will be explored in this research. In the switched-capacitor converter universe, there is plenty of work for single-output designs for various topologies. Most converters are reconfigurable to the different DC voltage levels apart from Dickson and cross-coupled charge pump topologies due to their boosting power stage architecture through a number of stages. However, existing multi-output converters are limited to the fixed gain ratio. This work explores the reconfigurable dual-output converter with adjustable gain to compromise the research gap. The thesis's primary focus is to present the inductor-less, switched-capacitor-based DC-DC converter power management system (PMS) supplied by a varying input of PV energy harvester input source. The PMS should deliver highly efficient regulated voltage conversion ratio (VCR) outputs to low-power wearable electronic devices that constitute multi-function building blocks.

Chemical vapour deposition (CVD) onto flat substrates has been researched extensively; however, little work has been on done on diamond deposition onto 3-D substrates. Diamond has excellent physical and chemical properties and has considerable potential for use in dental tools and biomedical implants. Since the 1950s sintered diamond burs have been used and are made using diamond particles bonded onto the substrate using a binder matrix material. The binder contains potentially poisonous components such as nickel and CVD technology eliminates the use of such binder materials. Hot Filament Chemical Vapour Deposition (HFCVD) uses a horizontal filament mounted above the substrate. For 3-D substrates the system was modified with the filament mounted vertically and the substrate held concentrically within the coil in a system called vertical filament CVD (VFCVD). Process optimisation was conducted on molybdenum wire and then diamond films were deposited onto metals such as titanium, molybdenum and tungsten carbide (WC-Co) burs. A pre-treatment was required on WC-Co burs using Murakami reagent was used for etching followed by acid etching to remove excess Co from the surface and improve adhesion. The growth rate, adhesion, surface roughness, composition and nucleation densities were all investigated. The substrate temperature influenced the compressive stress of the diamond films due to the thermal gradient, which is related to the position of the substrate within the filament. Machining tests showed that the wear rates of the coated diamond tools were considerably lower than the uncoated burs. These were quantified using a Figure of 5 Merit (F) which was then plotted against the number of holes drilled for uncoated, sintered and VFCVD diamond coated burs to assess the tool performances on human tooth material, acrylic and borosilicate glass. All of the tests showed that the diamond coated dental burs using the new VFCVD process demonstrated a superior performance compared to sintered and uncoated burs.

After working at Laboratory for Laser Energetics for about 10 months, I was assigned in doing the research for replacing the obsolete parts on the trigger board of the high voltage and high current system. After studying the system, it was noticed that the circuit topology used was part of the pulse power system. Hence, the pulse power system was studied further to understand how it was used and its advantages. The inductive adder topology was studied thoroughly so that the trigger board design would meet the requirements. The components such as MOSFETs and Gate Drivers were studied and compared so that the new design could replace the old trigger board design and that it would work better than before. In this project, the pulse power system and its different design topologies are explored. It was then focused on the inductive adder topology design. It will discuss how the final design of the trigger board came to be. Not only the new trigger board successfully replaced the old design but its transient time is better. The new trigger board design was also proved to operate faster than the trigger board design in Lawernce Livermore. The process has been documented in this paper in detail.

Cytoplasmic dynein-1 (dynein) is a microtubule-based motor protein that is essential for maintaining proper spatial and temporal organization of the cellular interior during both interphase and cell division. To do so, dynein carries out diverse functions including transport of intracellular cargos, organelle anchoring, mitotic spindle assembly and nuclear migration. To carry out these diverse functions, dynein is regulated by multiple factors including Lis1, dynactin and activating adaptors. In this thesis, I present interdisciplinary work investigating the mechanisms of regulation of dynein. In chapter 2, a combination of biochemistry, single-molecule assays and cryo-electron microscopy was used to investigate how yeast dynein is regulated by Lis1. Previous work showed that Lis1 binds directly to dynein’s AAA+ motor domain and slows its motility by causing dynein to tightly bind microtubules. The work presented here revealed that in addition to this role, Lis1 can also induce dynein to weakly bind microtubules. The mode of regulation used by Lis1 is determined by the nucleotide state at dynein’s third AAA domain and the stoichiometry of the Lis1-dynein interaction. Both modes of Lis1 regulation of dynein are required for dynein to position the mitotic spindle in yeast cells. In chapter 3, the mechanism of regulation of human dynein by Lis1 is investigated. Human dynein requires dynactin and an activating adaptor for directional long-distance movement on microtubules. The work presented here shows that Lis1 promotes the formation of a maximally activated dynein complex consisting of dynein, dynactin and an activating adaptor. Finally, in chapter 4, the identification of the dynein protein interactome is described. Two novel dynein activating adaptors, ninein and ninein-like, were discovered and shown to activate dynein/dynactin motility in single-molecule assays. Overall, the work presented here reveals novel insights into complex regulation of dynein., Biophysics

Combating coastal erosion is becoming increasingly challenging due to population growth near beaches, and the dynamic nature of nearshore morphological processes. Along a zeta-shaped coastline, such as Gold Coast in Australia, the degree of exposure of the beaches to waves varies alongshore depending on the incident wave direction. Since waves are one of the main drivers of sediment transport along the coast, changing wave direction can disturb the modal sediment transport. This phenomenon can cause localised erosion, and it is therefore important to quantify the impact at different locations along the coast. By doing so, effective coastal protection strategies can be developed to ensure the resilience of coastal communities. Recent studies have reported changes in wave climate (e.g., frequency and intensity of storms, shifts in wave direction) in response to climate change, making coasts more vulnerable to unusual waves. In addition to the waves, water levels play an important role in beach erosion, and the non-astronomical component of water levels (i.e., surge) presents a correlation with wave height during extreme storm events. Moreover, storm groups, where beach recovery is near zero between successive storms, may further increase erosion along the coast. Therefore, an investigation of the impact of waves, surge, and storm groups is important for effective coastal management. In this context, this study aimed to understand the beach response to extreme storms and storm groups on a zeta-shaped open coastline. This was achieved through analysis of (i) storm wave fields using different boundary forcing to study the wave transformations from offshore to nearshore, (ii) extreme joint probability of significant wave height and water level, and (iii) the response of different antecedent beach profiles induced by a storm group and its order. A numerical modelling approach was used, incorporating a spectral wave model and a morphological model for wave and beach erosion predictions, respectively. In addition, a technique using an artificial neural network (ANN) to perform spatial wave assimilation was used to improve wave hindcasting. [...]

This dissertation project investigates the historical development of states under severe fiscal constraints and in the presence of existing institutions in society. Focusing on British Burma as the key empirical case, it reveals how colonial governments responded to local political history and indigenous institutions that preceded colonial rule. To provide empirical evidence, the project develops original data on pre-colonial, colonial, and post-independence Burma, including one based on administrative records of the pre-colonial state in the eighteenth century. In Chapter Two, I explain the spatial variations in the development of state coercion under colonial rule. I introduce a theoretical framework linking pre-colonial history to colonial coercion and argue that early experience with state consolidation before colonization mitigated local society's contention with the colonial state, reducing colonial investments in coercion. For empirical evidence, I developed original data of headman appointment status from pre-colonial land revenue inquests in 1783 (sit-tans) and colonial police presence as recorded in 1912 and 1924 British Burma district gazetteers. Empirical findings show that locations exposed to pre-colonial state consolidation were less likely to have civilian and military police presence. Further evidence reveals that colonial police presence, whose infrastructure the present-day Burmese military inherited, left consequences for post-independence conflict; places with civilian and military police presence also had more post-independence conflict events in their vicinity. In Chapter Three, I introduce a formal model conceptualizing colonial education policy as a response to indigenous education institutions and resistance against colonial rule. In this model, government's decisions over whether to rely on indigenous institutions (indirect involvement) or replace them with a new system (direct involvement) determined education's ability to mitigate anti-colonial resistance. In this two-actor, two-period strategic interaction between the colonial government and indigenous society, while colonial government relied on indigenous education under low local resistance, increasing resistance fueled the perceived association between indigenous education and resistance against state control. This motivated governments to directly involve in education as they replaced indigenous education with a new system under stronger state control. The theoretical conclusions contribute to recent studies in political economy of education that examine how state interests in political indoctrination drove the rise of mass education in non-democratic states. In Chapter Four, I evaluate the utility of previous formal model in explaining the historical context of colonial education in British Burma. Based on its empirical implications, I hypothesize that direct educational involvement by the colonial state occurred when indigenous education level and anti-colonial resistance were both sufficiently high. Using original panel data of 33 British Burma districts over two decades (1901-20), when a transformation from earlier state reliance on Buddhist monastic education to a secular school system occurred. The findings suggest that significant increases in female enrollment, a key measure of state involvement as Buddhist monastic schools excluded women, occurred in districts with high Buddhist male literacy and high numbers of riots. Local factor endowments or the presence of Christian missionaries cannot explain the results. With these three substantive chapters, the dissertation highlights the interconnected relationships between pre-colonial history, anti-colonial resistance, and state development in coercion and education.

Following a series of serious disasters, in particular, Cyclone Nargis in 2008, the activities of third sector organizations throughout Myanmar became more apparent. They were seen providing emergency services, humanitarian aid and technical support for community development. This adds weight to the claim that insufficient service delivery by the state has resulted in the emergence and strengthening of voluntary civil society organizations to fill the gaps. This thesis is based on a case study of a voluntary civil society organization called the Yangon Rescue Organization (YRO) in Myanmar, which has been providing free ambulance services and emergency medical care for the community in Yangon City. Based on a qualitative case study approach using in-depth interviews, document analysis and social media observations, my research found that the YRO, as a voluntary civil society organization, is unique in its relations with the community, the state and other third sector organizations (such as international NGOs) and these relations undoubtedly contribute to community resilience.