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This report reviews social housing archetypes in Scotland to enable identification of suitable energy efficiency and zero emissions heating systems.

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13 TeV for Run 2, events with dense environments, such as in the cores of high-energy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of the order of the tracking detectors sensor granularity. Basic track quantities are compared between 3.2 fb$^{-1}$ of data collected by the ATLAS experiment and simulation of proton-proton collisions producing high-transverse-momentum jets at a centre-of-mass energy of 13 TeV. The impact of charged-particle separations and multiplicities on the track reconstruction performance is discussed. The efficiency in the cores of jets with transverse momenta between 200 GeV and 1600 GeV is quantified using a novel, data-driven, method. The method uses the energy loss, dE/dx, to identify pixel clusters originating from two charged particles. Of the charged particles creating these clusters, the measured fraction that fail to be reconstructed is $0.061 \pm 0.006 \textrm{(stat.)} \pm 0.014 \textrm{(syst.)}$ and $0.093 \pm 0.017 \textrm{(stat.)}\pm 0.021 \textrm{(syst.)}$ for jet transverse momenta of 200-400 GeV and 1400-1600 GeV, respectively. The European physical journal / C 77(10), 673 (2017). doi:10.1140/epjc/s10052-017-5225-7 Published by Springer, Berlin

In practice, the quest for the optimal operation of energy systems is complicated by the simultaneous presence of operating constraints, among which the need for producing the power required by the user, and of uncertainty. The latter concept incorporates the potential inaccuracies of the models at hand but also degradation effects or unexpected changes, such as, e.g. random load changes or variations of the availability of the energy source for renewable energy systems. Since these changes affect the optimal values of the operating conditions, online adaptation is required to ensure that the system is always operated optimally. This typically implies the online solving of an optimization problem. Unfortunately, the applicability and the performances of most model-based optimization methods rely on the quality of the available model of the system under investigation. On the other hand, Real-Time Optimization (RTO) methods use the available online measurements in the optimization framework and are, thus, capable of bringing the desired self-optimizing control reaction. In this article, we show the benefits of using several RTO methods (co-) developed by the authors to energy systems through the successful application of (i) “Real-Time Optimization via Modifier Adaptation” to an experimental Solid Oxide Fuel Cells (SOFC) stack, of (ii) the recently released “SCFO-solver ” to an industrial SOFC stack, and of (iii) Dynamic RTO to a simulated tethered kite for renewable power production. It is shown how such problems can be formulated and solved and significant improvements of the performances of the three aforementioned energy systems are illustrated.

Despite looming ecological disaster, a persistent state of insufficient action seems commonplace amongst most organizations. This thesis critically explores how this impasse is constituted by discursive struggles surrounding the global ecological crisis. These struggles are situated within the context of global environmental governance – a power arena that has, over the past 25 years, become a defining battleground regarding environmental sustainability. Here, discourses of the ecological crisis are constituted by political contests amongst, most notably, multinational corporations, civil society organizations, and (trans)national policy actors. This thesis draws mainly from post-structural discourse theory, coupled with critical perspectives on organizations and the natural environment, to explore both the discursive practices that fix meanings surrounding the global ecological crisis, and the power effects thereof. The primary source of data is text – this study is explicitly interested in how discourses of the global ecological crisis evolve as the natural environment is (mis)represented in organizational disclosures. Despite recognition by management and organization scholars that the natural environment is indeed constructed, a functional separation between business and nature persists, the relationship of which is mostly examined from a firm-centric perspective. However, sustainability issues such as climate change transcend the confines of firm activity and operate across spatial and temporal dimensions. Hence, there is an urgent need to reconsider the business-nature dualism. To do so, this study adopts a multi-level, multi-method approach that permits a necessary degree of analytical and theoretical flexibility. The four individual articles that encompass this work, whilst drawing from different theoretical approaches, along with focusing on different levels of analysis, are underpinned by the contentious intersection between discourse, organizations and the natural environment. The first article concerns ‘macro talk’ and, operating on the field level, explores how a dominant understanding of business’ role in sustainable development is constituted during the UN Earth Summits in 1992, 2002, and 2012. The second article regards ‘corporate talk’ and, this time on an organizational level, examines how tensions between economic growth and environmental protection are avoided by the European oil and gas supermajors—BP, Shell and Total—through the practice of mythmaking. The third article takes a longitudinal approach and, also concerning ‘corporate talk’, examines how BP rearticulated a hegemonic discourse of fossil fuels, which, when enacted, reproduces corporate inaction on climate change. Finally, the fourth article emphasizes ‘resistance talk’, focusing on how climate activists, as part of the global fossil fuel divestment movement, engage in certain micro-level practices as they attempt to stigmatize the fossil fuel industry. In all, the findings from these articles suggest that organizations both represent nature as something to be conquered, dominated, and valued economically and as a pristine wilderness to be preserved for the enjoyment of future generations. In pursuing these two extremes concurrently, organizations self-perpetuate a social-symbolic deadlock that hinders finding sustainable ways for human systems to coexist with natural systems. This thesis contributes mainly to literature on organizations and the natural environment by illustrating how certain practices, mechanisms, and processes continuously redefine the business-nature relationship by facilitating a discursive struggle across multiple spatial and temporal dimensions. In doing so, there are implications both for policy and business organizations, which are discussed in the concluding chapter of this work.

Secondary organic aerosol (SOA) is a major component of aerosol. Aerosol affect the radiation budget of the Earth and are detrimental to human health. Robust assessments of the impact of SOA on air quality and climatic are hindered by uncertainties in the SOA lifecycle. There are approximately 37 million unique organic compounds in the atmosphere. With such a large number of potential sources of SOA, representing the SOA lifecycle in a global model is challenging. SOA schemes within models vary in several ways, including: the emissions source types considered, and how volatile organic compound (VOC) physicochemical processing is treated. As a result, estimates of the global SOA production rate from models and observations range several orders of magnitude. Furthermore, simulated SOA concentrations from global models are typically lower than observed. The objectives of this study are to (i) quantify the impact of biogenic, anthropogenic and biomass burning VOC emissions on the global SOA budget and model agreement with observations, (ii) explore the sensitivity of the global SOA budget and model agreement with observations to variations in the physicochemical processing of VOCs, and (iii) examine how future changes in climate and emissions influence the SOA lifecycle. Throughout this study, a global chemistry-climate model (UKCA) is used, developed, and tested against a suite of surface and aircraft observations Firstly, the impact of biogenic, anthropogenic and biomass burning VOC emissions on the global SOA budget and model agreement with observation is quantified. This is achieved by introducing new VOC emission source types, whilst maintaining a fixed VOC oxidation mechanism. As source of SOA, monoterpene (C10H16) has been studied under laboratory conditions extensively. This VOC is commonly included in SOA schemes and, in many cases, is the only source of SOA. In this study, when monoterpene is the only source of SOA, the simulated global SOA production rate is 20 Tg (SOA) a-1 and the normalised mean bias (NMB) with respect to observed SOA is -91 %. In response to the addition of new emission source types, isoprene (C5H8), a lumped anthropogenic VOC (VOCANT) and a lumped biomass burning VOC (VOCBB), to the SOA scheme the global SOA production rate increases by 275 % (to 75 Tg (SOA) a-1), and model agreement with observations improves (NMB = -51 %). The improvement in agreement between simulated and observed SOA is primarily due to the inclusion of VOCANT, as opposed to isoprene or VOCBB. These results demonstrate that, under a single-step oxidation scheme, with a fixed yield of SOA, biogenic, anthropogenic, and biomass burning VOC emissions account for around half of the observed SOA abundance. With the new SOA scheme which considers all major VOC sources of SOA, the next objective is to explore the sensitivity of the SOA budget and model agreement with observations to variations in the physicochemical processing of VOCs. This is achieved by performing simulations with varying VOC deposition and oxidation mechanisms, whilst maintaining fixed VOC emissions. In light of recent field and explicit modelling studies, the sensitivity of SOA to VOC deposition is quantified. By including both dry and wet deposition of all VOC precursors of SOA, the global SOA production rate from all VOC sources reduces by 37 % (to 47 Tg (SOA) a-1) and model agreement with observations worsens (NMB = -66 %). Hence, neglecting VOC deposition can have significant impacts on SOA formation. According to chamber and field studies, VOCs form SOA after several generations of oxidation, and with yields which are sensitive to nitrogen oxide (NOX) concentrations. Therefore, for the anthropogenic and biomass burning VOC precursors of SOA (VOCANT/BB), model simulations are performed varying (a) the parent VOC reactivity, (b) the number of reaction intermediates, and (c) accounting for the influence of NOX on SOA yields. Both variations in parent VOC reactivity and accounting for the NOX-sensitive SOA yields have a substantial impact on simulated SOA, whereas SOA is mostly unaffected by the introduction of the reaction intermediate. In response to these variations in oxidation, the global SOA production rate from VOCANT/BB ranges from 18 Tg (SOA) a-1 to 45 Tg (SOA) a-1 (+150 %) and the NMB with respect to observed SOA ranges from -46 to -71 %. SOA is extremely sensitive to variations in parent VOC reactivity and accounting for the NOX-sensitive SOA yields, but is unaffected by the introduction of the reaction intermediate. These simulations highlight how the use of simplified VOC oxidation mechanisms within SOA schemes can have profound impacts on the global SOA budget and model agreement with observations. Finally, the impact of future changes in climate and emissions on the SOA lifecycle is quantified. This is achieved by driving the UKCA model with the Intergovernmental Panel on Climate Change (IPCC) Representative Concentration Pathway (RCP) 8.5 for the 2090s and the present-day (2000s). Compared to the present-day, climate change alone results in a 23 % increase in the global SOA burden due to increases in both SOA production (10 %) and the SOA lifetime (12 %). This climate-induced increase in SOA production is driven by an 82 % increase in monoterpene emissions due to the warming associated with RCP8.5 (4.6 °C). Global isoprene emissions reduce by 1 % under future climate change due to the opposing effects of warming and rising carbon dioxide concentrations which suppress isoprene synthesis (‘CO2 inhibition’). Projected changes in anthropogenic and biomass burning emissions alone result in a 3 % decrease in the global SOA load compared to the present-day due to a reduction in the SOA production rate (-6 %) and an increase in the SOA lifetime (4 %). This emissions-driven reduction in global SOA production is driven by a projected 11 % decrease in anthropogenic and biomass burning VOCs. When future changes in climate and emissions are combined, the global SOA burden increases by 20 % in the future compared to the present-day, which is due to increases in SOA production (4 %) and a lengthening of the SOA lifetime (15 %). Therefore, these results imply a growth in the global SOA burden due to rising biogenic VOC emissions and a lengthening of the SOA lifetime, despite reductions in anthropogenic and biomass burning emissions. This thesis contributes to the understanding of the SOA lifecycle in the present-day and the future. In relation to uncertainty in SOA and the impacts of SOA on air quality and climate, greater observational constraints on VOC emissions, deposition and oxidation mechanisms are required. Furthermore, these results imply a growing importance of natural sources of SOA in the future.

This report assesses the problems likely to be encountered in transmitting bulk electrical energy from a source tens of kilometers offshore to the mainland of the United Kingdom.