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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Analysis of health and environmental risks associated with Marcellus Shale development

Mitchell, Austin L. 01 December 2013 (has links)
The rapid growth of the shale gas industry has inspired questions concerning attendant apparent and potential short- and long-term health and environmental risks. My research examined three potential environmental and health risks. (1) For the last half-century the Northeast natural gas market was supplied from major producing areas in Texas, the Gulf Coast, and Canada. Because radon has a short half-life of 3.8 days, the time required to transport the natural gas from these areas to the Northeast resulted in a low-radon product being delivered to homes. As the Northeast gas market transitions to locally-produced natural gas the potential for radioactive decay will diminish and the natural gas being delivered to homes will contain radon at higher levels. I assess the lung cancer risk for people living in homes with unvented gas cooking (approximately half of the homes in the Northeast) and heating appliances, which are in fewer homes. Data on the locally-produced natural gas radon concentration are limited, but for the modeling assumptions considered the radon exposure is predicted to be small compared to typical residential exposures, and additional annual population-level risk will likely be much less than the error in the estimate of annual radon-induced lung cancers. An excess lifetime lung cancer risk >10-4 is possible for high gas usage in poorly ventilated settings. (2) High volume and locally-concentrated surface water withdrawals for Marcellus Shale development may pose a risk to water quality, aquatic and riparian ecosystems, and other uses of water resources. State environmental and interstate water authorities take different approaches to managing these water withdrawals. In the Upper Ohio River Basin, which covers the western third of Pennsylvania, the Department of Environmental Protection requires that all water used for shale gas development be covered by a water management plan. These plans stipulate the amount and timing of surface water withdrawals from each source as a function of annual stream flow statistics. Neighboring regulatory authorities and some environmental groups favor the use of monthly flow statistics instead, but implementation of these statistics in western Pennsylvania would require more data than are currently available. Because hydrologic data in the Upper Ohio River Basin are sparse, the use of the annual flow statistics is more likely than use of monthly flow statistics to prevent water withdrawals when aquatic ecosystems are under the greatest stress. The annual flow statistic might also result in fewer and smaller occurrences of computed ecodeficits under scenarios of development-related water demands in the future. (3) Improperly abandoned and orphan gas wells threaten human health and safety as well as pollute the air and water. Pennsylvania currently requires production companies to post a bond to ensure environmental reclamation of non-productive well sites, but the cost of plugging horizontally drilled wells and reclaiming well pads is estimated to be at least a factor of 10 greater than the current well bonds. The economics of shale gas development favor transfer of assets from large entities to smaller ones. With the assets go the liabilities, and without a mechanism to prevent the new owners from assuming reclamation liabilities beyond their means, the economics favor default on well-plugging and site restoration obligations. In addition to increasing the bond amounts, individual well trust accounts are proposed based on a model from the coal industry. Pre- and delayed-funding options (a fee and severance tax, respectively) to pay for future reclamation are examined from the perspective of the taxpayer. The exposure of the taxpayer to these financial liabilities and to a future orphan well problem can be minimized with minimal impacts to the profitability of gas production regardless of which funding option is used.
152

Quantification of performance and cost trajectory of Li-ion battery designs for personal vehicle electrification in the near future

Sakti, Apurba 01 December 2013 (has links)
Battery cost is among the largest barriers to mainstream adoption of electric vehicles. This dissertation examines near future battery technology and cost by (1) validating existing physics-based battery performance models using laboratory testing and manufacturer specifications, (2) constructing battery design optimization and production cost models to identify the least-cost design and investigating how key design-decision variables affect performance and cost for a variety of vehicle power and energy requirements, and (3) conducting expert elicitation on future battery costs and the key factors that drive cost. The validation, cost, and optimization modeling work use LiNi0.33Co0.33Mn0.33O2/LixC6 (NMC-G) as the chemistry of choice. Validation results of Battery Design Studio™ (BDS) a Li-ion battery modeling software indicated that BDS predictions of total energy delivered under our constant C-rate battery discharge tests are within 6.5% of laboratory measurements for a full discharge and within 2.8% when a 60% state of charge window is considered. Once validated, BDS is used to develop a power meta-model that predicts the 10–sec power capability of a cell design as a function of its capacity (Ah) and cathode coating thickness (microns). The production cost model is a process-based model and is constructed adopting process step information from existing literature. Subsequently, an optimization model is developed which estimates the cheapest cost battery pack design for a set of five different electrified vehicles (EVs) whereby the role of design-decision variables like cathode coating thickness is investigated among others. The energy and power requirements for the EVs, used as constraints in the optimization model, are calculated using the Powertrain Systems Analysis Toolkit (PSAT). Battery pack costs calculated are in the range of costs reported in the literature. Results indicate that higher capacity cells manufactured using higher electrode coating thicknesses can decrease manufacturing costs by 5-8%. Results suggest that economies of scale can be reached at a plant size of about 200MWh. Expert elicitation indicates that a variation of NMC-G is likely to be the cheaper cell-chemistry by 2018 with no major technological breakthroughs. Some experts also expect manufacturing improvements resulting in higher electrode coating thicknesses and cell capacities expected by 2018.
153

Atmospheric Impacts of Biofuel and Natural Gas Life Cycle Greenhouse Gas Emissions and Policy Implications

Schwietzke, Stefan 01 December 2013 (has links)
Many studies have recently reported estimates of greenhouse gas (GHG) emissions and associated potential climate impacts of biofuel and natural gas (NG) use. U.S. corn ethanol production keeps increasing under federal mandates, and NG production soars due to successful tapping of unconventional resources in North America, particularly shale gas. Numerous life cycle assessment (LCA) studies document technology specific corn ethanol and NG GHG estimates. The estimates often include all life cycle stages from fuel supply to combustion, and point out potential for emissions reductions. Several studies suggest that using GHG emissions as an evaluation metric underestimates corn ethanol’s radiative forcing (RF) impact – a precursor and indicator for global temperature change – by 10-90% over the next few decades. This emissions timing effect may overestimate (i) ethanol’s climate benefits over gasoline and (ii) the effectiveness of U.S. policies mandating and subsidizing ethanol. This work revisits the above studies, and builds upon existing models to quantify RF impacts across the corn ethanol life cycle. The emissions timing factor (ETF) is significantly smaller than previous estimates (2-13% depending on the chosen impact time frame), and the effect is dwarfed by uncertainty in the GHG emissions estimates. Nevertheless, ETF reduces ethanol’s probability of meeting the federal target of 20% GHG reduction relative to gasoline from 53% (according to EPA GHG estimates) to 7-29%. However, the small potential climate impacts from U.S. ethanol use may not actually be observable based on estimated initial increases in global average surface temperature of < 0.001 °C. About 25% of global primary energy production comes from NG, whose life cycle GHG emissions and potential future climate impacts from substituting coal are highly uncertain due to fugitive methane (CH4) emissions from the NG industry. Accurately quantifying the NG fugitive emissions (FE) rate – the percentage of produced NG, mainly CH4 and ethane (C2H6) – released to the atmosphere is challenging due to the size and complexity of the NG industry. Recent LCA estimates suggest that the current NG FE rate could be as high as 8% and 6%, from shale and conventional NG, respectively, and other bottom-up studies indicate even higher rates several decades ago. This work analyzes possible ranges of the global average NG FE rate based on atmospheric CH4, C2H6, and carbon isotope (δ13C-CH4) measurements recorded since 1984, and top-down modeling of their sources and sinks. Box-model, δ13C-CH4mass balance, and 3D-modeling results agree on best estimate NG FE rates of 3-5% (of dry NG production and dry NG composition) globally over the past decade, and 5-8% around 1990. Upper bound FE rates are 5% and 7% in 2010 and 2000, respectively. Best estimate and upper bound values may be overestimated because both assume lower bound emissions from oil and coal production as well as complete absence of natural hydrocarbon seepage. While LCA studies are useful for identifying processes with the greatest NG FE reduction potential, the recent high bottom-up estimates do not appear representative of the U.S. national average based on top-down modeling results. Given the steadily declining NG FE rates one may expect that further emissions abatement is possible if industry practices are further improved.
154

An Alternative Approach for Assessing and Implementing Autonomous Ground Robotic Systems

Matsumura, John M. 01 May 2012 (has links)
This research considers a different way to assess autonomous ground robotic systems for implementation into society. For the past two decades, autonomous mobile ground robotic systems have existed in the science and technology domain, but so far, have had only limited applications in the field. An ongoing assumption is that robotic systems must be capable of fitting into an existing infrastructure and way of doing things—one defined for human operators. However, this assumption and the approach designed around it are not well-suited for the advancement of autonomous robotics, especially when complex operations are concerned. This can be attributed, in part, to the challenges in the object recognition and reasoning research areas. While recent strides have been made, the larger context of developing object recognition and reasoning technology to achieve a performance criteria developed for human operation will result in a less optimum path than if a new approach and subsequent integration path were taken. While clearly there are political and cultural constraints that limit the degree to which a new approach can be adopted, this work looks beyond these barriers, specifically considering autonomous robotics in military convoy and commercial snow clearing operations. This research uses a two-tiered approach that separately addresses critical utility-based decision criteria, focusing on technological viability and risk first and then cost and economic viability second. This approach, unlike a single-step net assessment, may be more reflective of the actual decision path. Additionally, by structuring the problem in this way, current risk abatement methods can be made more effective and new ones can be emplaced. Further, assumptions that are either inadvertently designed-in or that unfairly discount benefits and externalities associated with autonomous robotics can be re-visited. Thus, by adopting a new approach that fundamentally changes the underlying concept of operation, implementation of autonomous robotics into complex operations may be achieved much sooner or at substantially lower cost than if the current approach were maintained.
155

The development of Australia's Oceans Policy: change and stability in a policy community

Vince, J January 2004 (has links) (PDF)
In December 1998, the Howard Government released Australia’s Oceans Policy, a major initiative focused at providing a framework for implementing integrated ecosystem based management of Australia’s vast marine domain. This thesis utilises a policy community approach to review the processes and institutions that led to the development of Australia’s Oceans Policy. It argues that despite significant policy change affected by both external and domestic policy drivers, a key element in shaping responses to the policy has been stability within the policy community shaped paradoxically by ‘offshore federalism’ that has made it difficult to implement a fully integrated oceans policy. Analysis of the development and implementation of the Australia’s Oceans Policy indicates that change to ocean related policies embodied in the policy framework have been driven by several interrelated factors. These include debates over appropriate management of resources within and between sectoral groups; coordination of marine resource management between state and Commonwealth governments; and Commonwealth commitments to international instruments. New institutional arrangements established by Australia’s Oceans Policy such as the National Oceans Office, National Oceans Ministerial Board, National Oceans Advisory Group and Regional Marine Plan Steering Committees, reflect a commitment towards integrated ocean management but at the same time confront the legal and jurisdictional framework established following a quarter century of ‘offshore federalism’.
156

Religion and public order in the 1790s

Callaway, Patrick Michael. January 2008 (has links) (PDF)
Thesis (MA)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Billy Smith. Includes bibliographical references (leaves 104-108).
157

Legislative policy-making a case study.

Keynes, Edward. January 1964 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 116-119).
158

States, housing and innovation the role of state housing finance agencies.

Scally, Corianne P. January 2007 (has links)
Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Planning and Public Policy." Includes bibliographical references (p. 190-199).
159

The influence of public policy on the development of California water law a brief historical review and summary of court decisions /

Hayes, William J. January 1911 (has links)
Thesis (Juris Doctor)--University of California, Berkeley, May 1911. / Includes bibliographical references (leaf 53).
160

Internet Price Discrimination, Self-Regulation, Public Policy and Global Electronic Commerce

Bailey, Joseph P. January 1998 (has links)
No description available.

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