6,576 research outputs found

    Reformulating aircraft routing algorithms to reduce fuel burn and thus CO2 emissions

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    During the UN Climate Change Conference (COP26), in November 2021, the international aviation community agreed to advance actions to reduce CO2 emissions. Adopting more fuel efficient routes, now that full global satellite coverage is available, could achieve this quickly and economically. Here flights between New York and London, from 1st December, 2019 to 29th February, 2020 are considered. Trajectories through wind fields from a global atmospheric re-analysis dataset are found using optimal control theory. Initially, time minimal routes are obtained by applying Pontryagin’s Minimum Principle. Minimum time air distances are compared with actual Air Traffic Management tracks. Potential air distance savings range from 0.7 to 16.4%, depending on direction and track efficiency. To gauge the potential for longer duration time minimal round trips in the future, due to climate change, trajectories are considered for historic and future time periods, using an ensemble of climate models. Next, fixed-time, fuel-minimal routes are sought. Fuel consumption is modelled with a new physics-driven fuel burn function, which is aircraft model specific. Control variables of position-dependent aircraft headings and airspeeds or just headings are used. The importance of airspeed in finding trajectories is established, by comparing fuel burn found from a global search of optimised results for the discretised approximation of each formulation. Finally, dynamic programming is applied to find free-time, fuel-optimal routes. Results show that significant fuel reductions are possible, compared with estimates of fuel use from actual flights, without significant changes to flight duration. Fuel use for winter 2019–2020 could have been reduced by 4.6% eastbound and 3.9% westbound on flights between Heathrow and John F Kennedy Airports. This equates to a 16.6 million kg reduction in CO2 emissions. Thus large reductions in fuel consumption and emissions are possible immediately, without waiting decades for incremental improvements in fuel-efficiency through technological advances

    Corporate Social Responsibility: the institutionalization of ESG

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    Understanding the impact of Corporate Social Responsibility (CSR) on firm performance as it relates to industries reliant on technological innovation is a complex and perpetually evolving challenge. To thoroughly investigate this topic, this dissertation will adopt an economics-based structure to address three primary hypotheses. This structure allows for each hypothesis to essentially be a standalone empirical paper, unified by an overall analysis of the nature of impact that ESG has on firm performance. The first hypothesis explores the evolution of CSR to the modern quantified iteration of ESG has led to the institutionalization and standardization of the CSR concept. The second hypothesis fills gaps in existing literature testing the relationship between firm performance and ESG by finding that the relationship is significantly positive in long-term, strategic metrics (ROA and ROIC) and that there is no correlation in short-term metrics (ROE and ROS). Finally, the third hypothesis states that if a firm has a long-term strategic ESG plan, as proxied by the publication of CSR reports, then it is more resilience to damage from controversies. This is supported by the finding that pro-ESG firms consistently fared better than their counterparts in both financial and ESG performance, even in the event of a controversy. However, firms with consistent reporting are also held to a higher standard than their nonreporting peers, suggesting a higher risk and higher reward dynamic. These findings support the theory of good management, in that long-term strategic planning is both immediately economically beneficial and serves as a means of risk management and social impact mitigation. Overall, this contributes to the literature by fillings gaps in the nature of impact that ESG has on firm performance, particularly from a management perspective

    A Decision Support System for Economic Viability and Environmental Impact Assessment of Vertical Farms

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    Vertical farming (VF) is the practice of growing crops or animals using the vertical dimension via multi-tier racks or vertically inclined surfaces. In this thesis, I focus on the emerging industry of plant-specific VF. Vertical plant farming (VPF) is a promising and relatively novel practice that can be conducted in buildings with environmental control and artificial lighting. However, the nascent sector has experienced challenges in economic viability, standardisation, and environmental sustainability. Practitioners and academics call for a comprehensive financial analysis of VPF, but efforts are stifled by a lack of valid and available data. A review of economic estimation and horticultural software identifies a need for a decision support system (DSS) that facilitates risk-empowered business planning for vertical farmers. This thesis proposes an open-source DSS framework to evaluate business sustainability through financial risk and environmental impact assessments. Data from the literature, alongside lessons learned from industry practitioners, would be centralised in the proposed DSS using imprecise data techniques. These techniques have been applied in engineering but are seldom used in financial forecasting. This could benefit complex sectors which only have scarce data to predict business viability. To begin the execution of the DSS framework, VPF practitioners were interviewed using a mixed-methods approach. Learnings from over 19 shuttered and operational VPF projects provide insights into the barriers inhibiting scalability and identifying risks to form a risk taxonomy. Labour was the most commonly reported top challenge. Therefore, research was conducted to explore lean principles to improve productivity. A probabilistic model representing a spectrum of variables and their associated uncertainty was built according to the DSS framework to evaluate the financial risk for VF projects. This enabled flexible computation without precise production or financial data to improve economic estimation accuracy. The model assessed two VPF cases (one in the UK and another in Japan), demonstrating the first risk and uncertainty quantification of VPF business models in the literature. The results highlighted measures to improve economic viability and the viability of the UK and Japan case. The environmental impact assessment model was developed, allowing VPF operators to evaluate their carbon footprint compared to traditional agriculture using life-cycle assessment. I explore strategies for net-zero carbon production through sensitivity analysis. Renewable energies, especially solar, geothermal, and tidal power, show promise for reducing the carbon emissions of indoor VPF. Results show that renewably-powered VPF can reduce carbon emissions compared to field-based agriculture when considering the land-use change. The drivers for DSS adoption have been researched, showing a pathway of compliance and design thinking to overcome the ‘problem of implementation’ and enable commercialisation. Further work is suggested to standardise VF equipment, collect benchmarking data, and characterise risks. This work will reduce risk and uncertainty and accelerate the sector’s emergence

    The place where curses are manufactured : four poets of the Vietnam War

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    The Vietnam War was unique among American wars. To pinpoint its uniqueness, it was necessary to look for a non-American voice that would enable me to articulate its distinctiveness and explore the American character as observed by an Asian. Takeshi Kaiko proved to be most helpful. From his novel, Into a Black Sun, I was able to establish a working pair of 'bookends' from which to approach the poetry of Walter McDonald, Bruce Weigl, Basil T. Paquet and Steve Mason. Chapter One is devoted to those seemingly mismatched 'bookends,' Walt Whitman and General William C. Westmoreland, and their respective anthropocentric and technocentric visions of progress and the peculiarly American concept of the "open road" as they manifest themselves in Vietnam. In Chapter, Two, I analyze the war poems of Walter McDonald. As a pilot, writing primarily about flying, his poetry manifests General Westmoreland's technocentric vision of the 'road' as determined by and manifest through technology. Chapter Three focuses on the poems of Bruce Weigl. The poems analyzed portray the literal and metaphorical descent from the technocentric, 'numbed' distance of aerial warfare to the world of ground warfare, and the initiation of a 'fucking new guy,' who discovers the contours of the self's interior through a set of experiences that lead from from aerial insertion into the jungle to the degradation of burning human feces. Chapter Four, devoted to the thirteen poems of Basil T. Paquet, focuses on the continuation of the descent begun in Chapter Two. In his capacity as a medic, Paquet's entire body of poems details his quotidian tasks which entail tending the maimed, the mortally wounded and the dead. The final chapter deals with Steve Mason's JohnnY's Song, and his depiction of the plight of Vietnam veterans back in "The World" who are still trapped inside the interior landscape of their individual "ghettoes" of the soul created by their war-time experiences

    Pastoralists and Predators in Alai: Political Ecology of Wildlife Management in Kyrgyzstan

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    The study is devoted to the human-environmental relationships in the post-socialist period of Kyrgyzstan. It addresses the human-wildlife conflicts using the example of the Alai Valley in the south of the country. Environmental and climatic characteristics of this highland valley provide suitable conditions for pastoralism and serve as habitat for wildlife. In recent decades, the natural landscape of the region came under increasing international attention with regard to nature conservation, sustainable land management and development projects. Historically, pastoralism has played a significant role for the economy of Kyrgyzstan. Following the dissolution of the Soviet Union, the collapse of state agricultural infrastructure facilities, veterinary care, loss of markets, and privatisation of the agricultural sector of the economy and other factors have led to a major downfall in the animal husbandry industry. The number of sheep and goats decreased from ten million in 1990 to four million in 2000. Nevertheless, pastoralism has considerable importance to the national economy and remains as the crucial income source for rural livelihoods in Kyrgyzstan. The post-socialist period of Kyrgyzstan has faced rapid socio-economic and political transformation which has resulted in changes not only to local livelihoods, but also in livestock husbandry, nature protection and wildlife management. In recent decades many pastoralists often complain about the increase in livestock depredation by wild predators. It is taking place despite the presence of state sponsored predator-control activity. From another side, there are public concerns about wildlife conservation. With the engagement of many environmental NGOs and mass-media, wildlife management issues have quickly become highly politicised in Kyrgyzstan. Becoming a Party to several global environmental conventions has increased the realisation of many projects funded by external donor organisations, and the implementation of their obligations for wildlife conservation, together, have substantially raised the profile of wildlife management in Kyrgyzstan at the international level. Moreover, since the independence of Kyrgyzstan, the territory of Protected Areas has increased by three times. Protected Areas are crucial to wildlife conservation and are promoted by the nature conservation community as a beneficial measure to the mitigation of human-wildlife conflicts. Despite this fact, livestock depredation by wild predators generates conflicts and has become a serious conservation issue. The study aims to better understand human-wildlife interrelationships in connection with pastoralism, protected areas and wildlife management in Kyrgyzstan. Wildlife related conflicts are analysed to determine the status of livestock depredation and to explore its linkages with rural livelihoods and wildlife conservation concerns in the Republic. The project design emphasises different utilisation strategies for the same area of rangelands, including the provision of fodder resources, wildlife habitat area, livestock grazing, and other uses by humans. Additionally, the focus of this study is directed towards a historical aspect of the region in relation to the development processes in the Alai Valley and use of its natural resources

    False Profits: An Analysis of Planning's Cult of Growth and the Demands of Justice

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    Degrowth planning and radical approaches have been minimally investigated within the planning department and teeter on the fringes of planning pedagogy. Planning methods have essentialized growth-approaches that yield opportunity and economic vitality. Planners have the power to spatially transform development and should have a role in the downscaling of society at all levels. Public planning is a major governmental institution that organizes and manages spatial development and prioritizes market needs and the facilitation of capital accumulation. The growth model is not sustainable model because of the planetary boundaries we exist under. The growth model functions under the assumption that all growth is beneficial and that there are unlimited reserves of resources for people to extract from. Unregulated free-market Capitalism and city/urban planning are at odds because planning should be used as a tool to mitigate uncertainty. Unregulation begets uncertainty and crisis. Degrowth is a model that subverts the market-fetishistic/Capitalistic nature of planning and the functioning of society. It can be used as a preemptive measure to reduce the effects of the current global economic, environmental, and social crises of extraction and exploitation. Degrowth’s aim is to retract the bounds economic systems at all levels.Master of City and Regional Plannin

    Command and Persuade

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    Why, when we have been largely socialized into good behavior, are there more laws that govern our behavior than ever before? Levels of violent crime have been in a steady decline for centuries—for millennia, even. Over the past five hundred years, homicide rates have decreased a hundred-fold. We live in a time that is more orderly and peaceful than ever before in human history. Why, then, does fear of crime dominate modern politics? Why, when we have been largely socialized into good behavior, are there more laws that govern our behavior than ever before? In Command and Persuade, Peter Baldwin examines the evolution of the state's role in crime and punishment over three thousand years. Baldwin explains that the involvement of the state in law enforcement and crime prevention is relatively recent. In ancient Greece, those struck by lightning were assumed to have been punished by Zeus. In the Hebrew Bible, God was judge, jury, and prosecutor when Cain killed Abel. As the state's power as lawgiver grew, more laws governed behavior than ever before; the sum total of prohibited behavior has grown continuously. At the same time, as family, community, and church exerted their influences, we have become better behaved and more law-abiding. Even as the state stands as the socializer of last resort, it also defines through law the terrain on which we are schooled into acceptable behavior. This title is also available in an Open Access edition

    Ecology and Applied Environmental Science

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    Ecology and Applied Environmental Science addresses the impact of contemporary environmental problems by using the main principles of scientific ecology. It offers a brief yet comprehensive explanation of ecosystems based on energy, populations, and cycles of chemical elements. The book presents a variety of scientific ecological issues and uses these to examine a range of environmental problems while considering potential engineering, scientific, and managerial solutions. It takes an engineering approach and avoids excessive biological detail, while introducing ecology with a systemic approach. The book examines categories of organisms as well as the physical and chemical processes that affect them. It refers to the dynamics of populations and analysis of their major mutual influences, elaborates on the roles of primary production, limiting factors, energy flow, and circulation of chemical substances in the ecosystems, and presents the basic functions of aquatic ecosystems. The author considers important issues related to environmental degradation of forests, aquatic habitats, coastal zones, other natural landscapes, and urban areas, includes a survey of problems related to waste and toxic and radioactive substances, and presents the greenhouse effect and impacts from climate change. He discusses environmental management prospects and the potential for technological control of pollution from liquid, solid, and gaseous waste. He also highlights existing tools for environmental management, ecological and social aspects of biodiversity and landscape protection, and the contrast between development and environment in combination with ideas about sustainability. The Open Access version of this book, available at http://www.taylorfrancis.com, has been made available under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 license
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