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The continued drive to reduce Greenhouse Gas (GHG) emissions in order to mitigate climate change has led to an increase in demand for low-carbon energy sources, and the development of new technologies to harness the available energy in the wind, waves and tides. Many controversies surround these technologies, however, particularly with regards to their economic cost, environmental impacts and the implications of the variability of their output for security of the electricity supply. In order to make informed policy decisions on future developments of the electricity system, it is necessary to address these controversies and confirm the environmental, economic and social sustainability of these new renewable generators. This thesis specifically examines two key issues: whether new variable-output renewable energy generators actually deliver a net reduction in greenhouse gas emissions over their lifetimes, and whether they produce a viable energy return on energy investment. Although renewable energy sources are themselves ‘carbon free’, GHG emissions (and energy consumption) occur during the construction, maintenance and decommissioning of the generator infrastructure required to convert this energy into electricity. Furthermore, the variability of the output power from such generators has implications for the operation of the grid - there may be a requirement for additional reserve capacity and the increased part-loading of conventional plant is likely to reduce its operating efficiency. Carbon and energy paybacks are measures of the time required for a new renewable installation to offset these life cycle impacts. The work presented in this thesis examines both the life cycle impacts and the GHG emissions displacement of variable renewable generation, using Great Britain as a case study, in order to provide a basis for significantly more robust and reliable estimates of carbon and energy paybacks. The extensive literature survey concentrates on two key areas: current calculation methodologies and estimates for life cycle carbon and energy consumption of power generators; and the marginal emissions displacement of variable renewable generation. A detailed life cycle assessment of the Pelamis wave energy converter is presented, which sets the embodied carbon and energy in the context of the wider environmental impacts and includes an examination of the effect of different assumptions on the analysis results. In order to investigate the true emissions displacement of renewable generation, a historical analysis of real data from the National Grid was carried out, identifying the marginal displacement factor of wind power and taking into account the effect of the efficiency penalties of conventional plant. The findings of the analyses presented in this thesis are combined with information from the literature to examine the actual carbon and energy payback of existing renewable generation infrastructure on the British grid, and to provide detailed recommendations for future carbon and energy payback calculations.

Fossil tracks represent the only direct record of behaviour and locomotion of extinct animals. A computer model using finite element analysis (FEA) has been developed to simulate vertebrate track formation in cohesive substrates. This model has been designed for, and successfully run on, high performance computing (HPC) resources. A number of individual studies were carried out using the computer model to simulate both abstract indenters and virtual dinosaur autopodia. In addition to the simulation studies, two fossil tracks were described, including the first report of bird tracks at the Mammoth Site of Hot Springs, South Dakota (USA) and a re-description of a 'dinosaur tail drag' as the trace of a crocodilian. Using the computer model, it has been shown that in a wet, soft mud the indentation of a non-webbed virtual tridactyl foot created a resultant track with features analogous to 'webbing' between digits. This 'webbing' was a function of sediment deformation and subsequent failure in 3D, specific to rheology. Apparent webbing impressions were clearly developed only within a limited range of sediment conditions and pedal geometry. Indenter (pedal) geometry and morphology affect track depth independently of substrate and loading parameters. More complex morphologies interact with the cohesive substrate creating a lower effective load than that applied. In non-cohesive substrates such as sand, this effect is reversed, and it is the more compact morphologies that indent to a lesser degree. Virtual sauropod tracks were modelled, based on published soft tissue reconstructions of autopodia anatomy, and published mass/centre of mass estimates. It was shown that foot morphology and differential loading between fore- and hind- limbs leads to a range of substrates in which only the manus or pes are able to generate tracks. This offers a new mechanism for the formation of manus-only sauropod trackways, previously interpreted as having been made by swimming dinosaurs. A series of tracks were simulated using input data (loads, pedal morphologies) from four different dinosaurs (Brachiosaurus, Tyrannosaurus, Struthiomimus, and Edmontosaurus). The cohesive substrates used displayed a 'Goldilocks' effect, allowing the formation for tracks only for a very limited range of loads for any given foot. In addition, there was a strong bias toward larger animals, both in homogeneous and theoretically heterogeneous substrates. These findings imply that interpretations from track assemblages must consider that only a small proportion of the total fauna present may be recorded as a track assemblage due to substrate properties. The use of FEA to simulate dinosaur track formation has been shown to be successful, and offers a number of advantages over physical modelling including; consistency between experiments, specific control over input variables, rapid undertaking of repeatable experiments, and the ability to view subsurface deformation non-destructively. It is hoped that this work will lead to an increased interest in modelling tracks, and offer a quantitative method for studying fossil tracks.

Environmental and carbon footprints have recently come to the fore of the media’s, governmental and general public’s attention. They offer an excellent indication of humanity’s demands upon Nature and allow evaluation of ecological deficit by contrasting supply and demand. The ecological debt many nations find themselves in is unsustainable, globally inequitable and adds to the growing effects of climate change. These footprints need to be further investigated, looking at historic and future trends in order to better understand, not only the global overuse of natural capital, but also the imbalance between nation states of the world. The value and limitations of the footprint must be recognised; the footprint alone cannot represent the full anthropogenic impacts upon the Earth. This thesis focuses on developing the definitions of the ecological and carbon footprints, analysing the significant factors that affect their composition. The selected parameters are diverse, ranging from a host of economic, geographic and climatic factors. It is shown that both the carbon and ecological footprints are primarily driven by economic welfare, a result that reflects the consumptive nature and fundamental basis of the footprint. Analysis of the resultant correlating equations, for both the environmental and carbon footprints, highlights the differences between the developing and industrialised world in terms of their profligate or frugal use of Nature’s resources. This concludes the stark contrast between these regions of the globe in terms of their per capita and total footprint values. The disparity between the populous South and the prosperous North is further investigated to the year 2100, with the use of Intergovernmental Panel on Climate Change’s scenarios and adaptation of the correlating ecological footprint equation. Four separate scenarios are adopted, each having different underlying assumptions regarding economic development, demographic transition and environmental awareness for various regions of the world. For all scenarios the Southern regions rapidly increase their levels of total ecological footprint; in contrast the industrialised world maintains a relatively conservative evolution. Although different scenarios suggest contrasting future pathways, the hope of contraction and convergence among global footprint levels is not completely lost. The intensification of carbon emissions from both the affluent North and the majority South are considered with respect to population, economic and energy use trends from 1900 to the end of the twenty-first century. It is overwhelmingly shown that affluence will drive growth in carbon emissions across the world by the end of the century. Global inequality must be reduced; the footprint is utilised to demonstrate the trends in resource misuse and contrast between the ecological debtors and ecological creditors of the world.

Using panel data analysis, the study examines the impact of risk management factors oncarbon emissions. This method allows us to analyze data from multiple sources over time,providing a comprehensive picture of the relationship between risk management and carbonemissions.The panel data analysis would involve analyzing the relationship between the riskmanagement factors and carbon emissions over time while controlling for other factors such asindustry and financial performance that may influence emissions levels. This type of analysis canhelp identify which risk management practices are most effective at reducing carbon emissionsand can inform policy decisions aimed at mitigating climate change. The data collected covers aperiod of three years and includes various variables such as those related to firm governance andrisk management in carbon emissions, total revenue, Cost of Goods Sold (COGS), net income,and CO2 emission. Additionally, the study considers the number of employees as a measure ofthe firm’s size. The results of the study reveal that there is a negative correlation between carbonfootprint and risk management factors, which implies that as risk management factors increase,carbon emissions decrease. This finding suggests that implementing effective risk managementstrategies can lead to significant reductions in carbon emissions. The study provides valuableinsights for policymakers and businesses in addressing the challenge of reducing carbonemissions while also ensuring financial stability. The findings can also help firms make informeddecisions about investments in sustainable technologies and practices to reduce their carbonfootprint. Various models have been implemented to extract the results, including fixed effects,random effects, first differences, and between estimators.

This thesis presents the design and computational optimization of a two-axis nano-positioning stage. The devised stage relies on double parallelogram flexure bearings with under-constraint eliminating linkages to enable motion in the primary degrees-of-freedom. The structural parameters of the underlying flexures were optimized to provide a large-range and high bandwidth with sub-micron resolution while maintaining a compact size. A finite element model was created to establish a functional relationship between the geometry of the flexure elements and the stiffness behavior. Then, a neural network was trained from the simulation results to explore the design space with a low computational expense. The neural net was integrated with a genetic algorithm to optimize the design of the flexures for compactness and dynamic performance. The optimal solutions resulted in a reduction of stage footprint by 14% and an increase in the first natural frequency by 75% relative to a baseline design, all while preserving the same 50mm range in each axis with a factor of safety of 2. This confirms the efficacy of the proposed approach in improving stage performance through an optimization of its constituent flexures.

Abstract: The Highland Valley Copper (HVC) porphyry Cu (±Mo) district is Canada’s largest and longest operating mine. Globally, exploration expenditure has been increasing, yet very few new resources have been discovered, despite the anticipated Cu demand for the future. Hosted in the Triassic Guichon Creek batholith (GCB) in the Cordillera of British Columbia, the HVC district is an excellent site to study the distal expression of porphyry Cu systems, integrate disparate data sets, and develop new exploration tools and models to aid the discovery of porphyry Cu deposits for the next generation. This study aimed to determine the diagnostic features of the rocks and minerals peripheral to the prolific HVC porphyry Cu centers– the footprint. Specifically, how, to what degree, and to what distance are the rocks outside of the porphyry centers affected by hydrothermal processes? Can vein mineral chemistry be used to vector to Cu mineralization and identify the presence of a porphyry system? Was there an external fluid entrained in the magmatic-hydrothermal systems in the porphyry Cu centers, and what was its origin? Whole-rock lithogeochemistry, mineral geochemistry, and a combination of stable (H, O, C and B) and radiogenic (Sr) isotope techniques are used to address these questions. The HVC district is hosted in calc-alkalic plutonic rocks of the GCB. Well-developed, feldspar-destructive, white-mica–chlorite alteration is indicated by (2Ca+Na+K) /Al values 0.75 wt. % calcite and have measured 13Ctotal values > -10 ‰. Up to 6 km away from Cu mineralization, propylitic, sodic-calcic, and a few least-altered rocks have 13Ctotal values between -11 and -7 ‰ that contrast with lower whole-rock 13Ctotal values (-25 and -21 ‰) in more distal propylitic alteration and fresh rocks. Calcite is interpreted to have formed via CO2 degassing from a late-stage magmatic volatile phase that contained ~1.6 mol. % CO2 in H2O.Estimates of δ18Ofluid and δDfluid values derived from epidote and tourmaline in sodic-calcic domains range from 3.0 to 8.2 ‰ and -40.6 to -3.9 ‰, respectively, which contrasts with the dominantly magmatic fluid values from Cu-mineralized potassic and white-mica–chlorite alteration facies. Tourmaline δ11Bfluid values range from 4.2 to 18.3 ‰. The highest δ11Bfluid values occur in albite-altered rocks and indicate a fluid source rich in 11B, such as seawater or seawater-derived formation water in country rocks. Sodic-calcic alteration is interpreted to be caused by the inflow and heating of seawater-derived fluid along regional-scale fracture-sets at low water–rock ratio (~0.01–0.1), and locally mixed with magmatic fluids in and adjacent to the porphyry centers. Epidote veins from the fertile HVC porphyry district can be discriminated from the epidote occurring in non-prospective geological environments by a combination of compositional features: large positive Eu anomaly, low sum HREE concentration, moderate negative REEN slope, and principally by analyses of >30 ppm As and Ge, and >10 ppm Sb. A coherent domain of epidote veins with a Ge anomaly (>30 ppm) forms a halo around the porphyry centers for ~ 5 km. Epidote veins with the highest As and Sb values (~ >20 ppm) occur within ~4 km of the porphyry Cu centers. The elements Mn (>6000 ppm) and Zn (> 25 ppm) are most enriched in epidote between 1.5 and 4 km of the porphyry centers, whereas Pb enrichment (~>120 ppm) occurs between ~ 4–6 km away. Prehnite veinlets are enriched in Mn (>2500 ppm) between 3 and 6 km away from the porphyry centers, and enriched in Pb (~>130 ppm) within a window of ~ 5.5–8 km. The pathfinder metals in epidote are interpreted to be primarily sourced from outflowing H2S-depleted, cooling, magmatic volatile phase emanating from the porphyry Cu centers or from the fringes of the subjacent cupola.Collectively, these results demonstrate methodologies and approaches that will be useful in elucidating hydrothermal footprints in porphyry Cu systems globally.

This thesis explores a novel detection architecture for use in a Direct-Detect Flash LIDAR system. The proposed architecture implements detection of the last two surfaces within single pixels of a target scene. The novel, focal plane integrated detector design allows for detection of objects behind sparse and/or partially reflective covering such as forest canopy. The proposed detector would be duplicated and manufactured on-chip behind each avalanche photodiode within a focal plane array. Analog outputs are used to minimize interference from digital components on the analog input signal. The proposed architecture is a low-footprint solution which requires low computational post-processing. Additionally, constant fraction discrimination is used to mitigate range walk.The proposed architecture is designed in 90nm CMOS technology. The footprint is 170.1 µm² with the largest transistor dimension being 22 µm. The design is easily expandable in hardware to allow additional surfaces to be detected.

Intervertebral disc extrusion (IVDE) is the most common cause of acute spinal cord injury (SCI) in dogs, and chondrodystrophic breeds such as the dachshund are commonly represented in the literature. The high incidence of spontaneous SCI in dogs makes them an important large animal model for human SCI. Clinical evaluation of dogs with SCI has historically focused on locomotor scoring and only a crude assessment of the `presence’ or `absence’ of nociception. The development of repeatable, sensitive and objective outcomes measures are of immense importance in establishing dogs with spontaneous SCI as a successful model for human SCI. Clearly defined outcome measures would allow for the identification of potential interventional therapy that may progress into clinical trials in humans. The goals of this study were to (1) identify differences in sensory threshold (ST) values between normal dogs and dogs with spontaneous IVDE and (2) to identify differences in footprint parameters between normal dogs and dogs with spontaneous IVDE to be used as outcome measures from SCI.Twenty normal dogs and 29 dogs with 30 discrete incidences of spontaneous SCI due to acute IVDE were prospectively enrolled for both studies. Sensory threshold (ST) was measured using an electric von Frey anesthesiometer (VFA) in all limbs of normal dogs at three separate time points and SCI-affected dogs at day 3, 10 and 30 following decompressive surgery. ST values were compared between groups and correlated with locomotor recovery in SCI-affected dogs. ST values were significantly higher (consistent with hypoalgesia) in the pelvic limbs of SCI-affected dogs at day 3, day 10 and day 30 when compared to normal dogs while no significant difference in thoracic limb ST values was observed between groups. A progressive decrease in pelvic limb ST values occurred in SCI-affected dogs over time, consistent with improvement toward normal sensation or development of allodynia. This finding correlated inversely with locomotor score. A significant overall decline in ST values across testing sessions was observed for all limbs of normal and SCI-affected dogs. This finding may be related to patient acclimation, operator training effect, or effect of analgesic medications. Footprint parameters of stride length (SL), base-of-support (BS) and coefficients of variance (COV) were made using a simple `finger painting’ technique in all limbs of the same 20 normal dogs and 29 dogs with 30 discrete incidences of IVDE. Measurements were made at three separate time points in normal dogs and on day 3, 10 and 30 following decompressive surgery in dogs with SCI. Values for SL and BS were compared between groups at each time point. Mean SL in all limbs was significantly lower in SCI-affected dogs at day 3, 10 and 30 compared to normal dogs. The COV of SL was significantly higher in both thoracic limbs and one pelvic limb in SCI-affected dogs only at day 3 following surgery compared to normal dogs. Additionally, BS in the thoracic limbs was found to be significantly higher in SCI-affected dogs at day 3 and day 30 following surgery compared to normal dogs. BS-PL was not significantly different between SCI-affected dogs and normal dogs.

The intent of this study was to analyze water use across a range of regions, scales and practices of the U.S. pork industry. A Life Cycle Assessment of water use within the pork supply chain was performed. Cumulative water use was the environmental impact category used in the LCA to evaluate the impacts of pork production processes throughout the pork supply chain. The functional unit for the analysis was the volume of water required to produce one kilogram of swine (live weight) at the farm gate. A comprehensive literature review was used to design and propagate algorithms for the National Pork Board Pig Production Environmental Footprint Calculator (version 2.0). The outputs from the calculator were used to generate lifecycle inventory inputs for unit processes in SimaPro (Pre' Consultants, The Netherlands), an LCA modeling program. The LCA method was then used to assess the water footprint for swine production from cradle to farm gate production scenarios. There were 240 different scenarios analyzed that were a combination of ten regions, three production strategies and three scales. The grow/finish barn phase of the on farm water footprint requires approximately five times as much water as the sow and nursery barns irrespective of the barn infrastructure. Water used to irrigate swine feed crops contributed 89% of the total cradle to farm gate footprint. Since all 240 scenarios were analyzed with the same ration inputs, the final footprints did not vary drastically between scenarios. There were small deviations such as tunnel ventilated production systems consistently required more water than hoop barns due to cooling systems in warmer regions. Smaller scale operations consistently had higher water footprints due to economy of scale, although the footprint differences between scales were marginal. Regarding the water use that occurred on the swine farm, drinking water was by far the most significant contributor to the footprint (81%). Production strategies, production scale and region of production were all statistically significant (p < 0.0001) and affected the blue water footprint. This may seem self-evident, but these processes have not been quantified at this scale prior to this analysis.

This research developed a corporate tax framework that delivers sustainable economic and environmental outcomes. Companies that sustainably improve their use of environmental resources receive a benefit in the form of a tax offset. The thesis is positioned within the sustainability and environmental policy contexts. The research highlighted a gap in models or frameworks that link environmental sustainability and corporate outcomes with tax policy. Determining how the company income tax system can facilitate sustainable business practices requires an understanding of incentives as drivers of behavioural change as well as business attitudes and approaches to environmental issues and environmental tax policy. This background analysis and literature review provides the structure for the framework – how a taxation system is designed is critical for its effectiveness. The methodology is based on the concept of sustainable development and how it is measured. Given the broadness and complexity of this topic, multi-criteria analysis is used to determine which indicators are to be analysed as viable measures for the framework. The Footprint was selected as the measure of changes in corporate sustainability. A broad outline of the concept is that, as a company becomes more sustainable, its average marginal tax rate decreases. This is achieved by linking the Footprint with the statutory tax rate. The scope of the thesis is restricted to developing the framework and the operation of the tax offset. Determining the Footprint measure and the Footprint rate will be the subject of further research. As an incentivised system, it has the potential to considerably increase R&D spending and investment in sustainable technologies and improve the efficiency of business processes without compromising revenue. It is structured so as to avert the trade-offs and/or conflicts normally associated with injecting environmental concerns into fiscal policies. It does this by aligning economic and environmental goals with drivers of corporate decision-making. The framework is transparent and broad-based, able to be applied broadly across and within all industry sectors. Being a tax-offset, adoption will be voluntary thereby minimising any resource allocation bias and compliance costs. It also facilitates accountability with respect to the sustainable use of resources.

This thesis examines the rhetorical and visual manifestations of race as they figured in the months prior to and within the 2006 New Orleans mayoral election discourses, and examines how the Nagin campaign tapped into a strategy that capitalized upon pre-existing racial tensions exacerbated by Katrina in order to win re-election. Much of the research for this thesis emerged from the making of a documentary film that examines the intersection between race and politics within this same election, and draws upon primary source video interviews conducted between February - May, 2006, and secondary source media and communications materials to posit that race rendered all political response to Katrina impotent, and that the reductive discourse of a racialized campaign was founded upon traditional, outmoded, and predictable interpretations of racial differences facilitated by socioeconomic hierarchies that both provided a structure for and allowed the psychological framework for such a strategy to work.