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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.
361

Three essays on the effectiveness of Oregon's land-use planning system : economic analysis with quasi-experimental methods

Dempsey, Judith 14 May 2012 (has links)
Oregon's land use planning system is often recognized as having been successful in its goals of limiting urban sprawl and protecting resource lands from development. However, it is difficult to quantify the impact of these regulations, because we cannot observe what would have happened in the absence of land use planning. The three essays in this dissertation explore the effects of Oregon's land use planning regulations on development patterns in the state, and also examine how the land use regulations are administered at the local level. The first essay in this dissertation asks if Oregon’s land use regulations have successfully restricted sprawl outside of urban areas. Urban containment policies, including Urban Growth Boundaries (UGBs), are a common tool used by city planners to promote compact development. We analyze how well UGBs do in containing development using fine-scale GIS data on cities in Oregon. Earlier studies on UGBs yield mixed results, with some authors finding no effects of UGBs on housing market variables and urbanization rates and others finding significant effects. A challenge in measuring these effects is that the location of the UGB is unlikely to be an exogenous determinant of a land parcel's value for development. The panel structure of our dataset allows us to estimate the UGB's effect on the probability of development using a difference-in-difference estimator. This estimator controls for time-invariant unobservable variables and common temporal effects among parcels, thereby mitigating the potential for biased estimates due to the endogeneity of the UGB's location. We also pursue a novel approach to controlling for time-varying factors inspired by regression discontinuity design. We find that UGBs are effective in containing development in many of the Oregon cities we examine, although there are some cities in which development rates are the same inside and outside of the UGB. Our results show that we would greatly overstate the effects of the UGBs were we to evaluate cross-sectional differences in development rates, as is common in previous studies. Besides the creation of UGBs, another goal of Oregon's land use regulations is to encourage citizen involvement in the planning process. The second essay in this dissertation examines the use of voter annexation as a form of citizen involvement. More specifically, this paper addresses the following two questions. First, does voter annexation cause changes in city demographics and characteristics? Second, assuming that a city votes for amendments and annexations to the UGB and city limits, what factors impact the outcome of the vote? We analyze the first question using the method of propensity score matching, which has not previously been used to explore this topic. This allows us to account for the endogeneity that stems from the fact that cities with certain characteristics may be more likely to use voter annexation in the first place. The second question, which is only evaluated for cities that employ voter annexation, is analyzed with the use of the logit model. Oregon's land use regulations must be approved at the state level, but are administered locally. Therefore, unlike past studies, we are able to isolate specific differences in the way the program is administered, and are not evaluating the stringency of the program itself. Previous studies have found that voter-approved annexation causes developers to provide more public goods and increase the scale of development, thereby shifting community demographics. Once a land use decision is on the ballot, it is also noted that cities that are whiter, wealthier, and more liberal are more likely to pass referenda that promote preservation and restrict development. For the first question, we compare specific demographic indicators between the two groups of cities. Contrary to the results of previous studies, we find no effect of voter annexation on these indicators. Our results for the second question indicate that the characteristics of the voting process itself impact the outcome more than community characteristics, which also differs from the results of previous analyses. The third essay in this dissertation is an extension of the first essay, and focuses on the impact of Oregon's land use regulations on the protection of land in riparian corridors and land that has been designated for exclusive farm use (EFU). Riparian corridors are protected with the use of Oregon Goal 5, which focuses on development of natural resource lands inside of UGBs, while EFU land is protected with the use of Oregon Goal 3, which focuses on protection of agricultural land at the county level. The LCT dataset that was used in the first essay is also used in this essay. EFU land by definition has no probability of development in the initial period. Land located in riparian corridors may also face different initial levels of protection than other land. We deal with this endogeneity, and also account for location inside or outside of a UGB, with the use of the difference -in-difference-in-differences estimator. This is an approach that has not been used to explore the effect of Oregon's land use regulations on these land categories. Most of the past studies that have examined the impact of land use planning on development of agricultural land in Oregon have relied on analysis of general trends and indicators, and have concluded that land use regulations have been successful in protecting this land. Previous research on riparian zone protection has focused on protection of aquatic wildlife, and for the most part has not examined the protection of riparian corridors inside of UGBs. The limited studies that have studied the effect of these regulations in UGBs have determined them to be effective in slowing, but not stopping, development in these areas. Overall, we find that Oregon's land use regulations have been successful in protecting both county level agricultural land and riparian corridors located inside of UGBs from development. It is less clear whether these regulations have protected riparian corridors located inside of UGBs from other anthropogenic uses. / Graduation date: 2012
362

Arsenic Contamination in Groundwater in Vietnam: An Overview and Analysis of the Historical, Cultural, Economic, and Political Parameters in the Success of Various Mitigation Options

Ly, Thuy M 01 May 2012 (has links)
Although arsenic is naturally present in the environment, 99% of human exposure to arsenic is through ingestion. Throughout history, arsenic is known as “the king of poisons”; it is mutagenic, carcinogenic, and teratogenic. Even in smaller concentrations, it accumulates in the body and takes decades before any physical symptoms of arsenic poisoning shows. According to the World Health Organization (WHO), the safe concentration of arsenic in drinking water is 10 µg/L. However, this limit is often times ignored until it is decades too late and people begin showing symptoms of having been poisoned. This is the current situation for Vietnam, whose legal arsenic concentration limit is 50 µg/L, five times higher than the WHO guidelines. Groundwater in Vietnam was already naturally high in arsenic due to arsenic-rich soils releasing arsenic into groundwater. Then, in the past half century, with the use of arsenic-laden herbicides dispersed during the Vietnam War and subsequent industrial developments, the levels of bio-available arsenicals has dangerously spiked. With the proliferation of government-subsidized shallow tube-wells in the past two decades, shallow groundwater has become the primary source for drinking and irrigation water in Vietnam. This is a frightening trend, because this groundwater has arsenic concentrations up to 3050 µg/L, primarily in the +3 and +5 oxidation states, the most readily available oxidation states for bioaccumulation. This thesis argues that measures must be taken immediately to remedy the high concentration of arsenic in groundwater, which in Vietnam is the primary and, in some cases, the sole source of water for domestic consumption and agricultural production. Although there are numerous technologies available for treating arsenic in groundwater, not all of them are suited for Vietnam. By analyzing the historical, cultural, economic, and political parameters of Vietnam, several optimal treatments of groundwater for drinking water emerged as most recommended, a classification that is based on their local suitability, social acceptability, financial feasibility, and governmental support. Further research on irrigation water treatment is proposed due to the need for sustainable crop production, the safe ingestion of rice and vegetables, and the continued growth of Vietnam’s economy, which is heavily dependent on agriculture.
363

Methane Production by a Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water

Thomson, Sean Richard 01 December 2014 (has links) (PDF)
Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping. In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced by reciprocation mixing to decrease pumping costs and the risk of media clogging. Three packed-bed digesters containing walnut shells as media were constructed at the on-campus dairy and studied for about six months. Over that time, several organic loading rates (OLRs), measured as both chemical oxygen demand (COD) and volatile solids (VS) were applied to the new packed-bed digesters to allow modeling of methane production. The influence of temperature on methane production was also investigated. Additionally, the study measured solids accumulation in the walnut shell packed-bed as well as the effectiveness and durability of walnut shells as packing media. Finally, a simple economic analysis was developed from the methane model to predict the financial feasibility of packed-bed digesters at flush water dairies under similar OLR conditions. Three methane production models were developed from organic loading: saturation-type (following the form of the Monod equation), power and linear. The models were evaluated in terms of regression analysis and the linearity of experimental to predicted methane production. The best model was then chosen to develop the economic predictions. Economic predictions for packed-bed digesters were calculated as internal rate of return (IRR) using the methane models along with additional input variables. Comparisons of IRRs were made using electric retail rates of $0.10 to $0.20 per kilowatt-hour and capital cost subsidies from zero to 50%. Sludge accumulation in the packed-bed was measured via change in porosity, and walnut shell durability was measured as the change in mass of representative walnut shells over the course of the study. The linear-type model of methane production from volatile solids OLR best represented this data set. Digester temperature was not found to influence methane production in this study, likely due to the small daily average ambient temperature range experienced (14°C to 24°C) and the greater influence of organic loading. Porosity of the walnut shell packed-bed decreased from 0.70 at startup to 0.34±0.06 at the end of the six-month study, indicating considerable media fouling. Sludge accumulated in each digester from zero at startup to 281±46 liters at termination. Walnut shells in the packed-bed lost on average 31.4±6.3% mass during the study period which may be attributed to degradation of more readily bio-degradable cellulose and hemi-cellulose within the walnut shells. Given the predicted methane production and media life, at present, the economic outlook for packed-bed digesters at commercial dairies is quite dependent on utility electrical rates, available subsidies and future improvements to packed-bed digester technology. The predicted IRRs ranged from below 0% (at 0% capital subsidy and $0.10/kWh) up to 25% (at 50% capital subsidy and $0.20/kWh) at large dairies (3000 milking cows). Increases in organic loading were not shown to necessarily increase IRR, particularly at OLRs above 10 g/Lliquid-d (as COD or VS). Ultimately, to better assess the value of packed-bed digesters for flush dairies, additional study is needed on topics such as sludge accumulation prevention, long-term walnut shell degradation, dairy barn flush water mixing, and more detailed economic analysis.
364

Economic aspects of the Boulder Canyon Project

McKaig, Leonard 01 January 1929 (has links) (PDF)
The recent passage of the Swing-Johnson bill by Congress and its approval by the President has been the signal for a general rejoicing throughout the West, and especially in Southern California, the section to be meet directly benefited by this legislation. There has been a widespread feeling that the long fight for Federal development of this great western river is over, and that we may begin shortly to realize some concrete returns upon our investment. Press reports indicate that many are already seeking work on the construction of the dam at Black Canyon, in anticipation of the immediate launching of the project. · "Wild cat" employment agencies have sprung up and are extorting fees from work-seekers by promises of good positions on the construction job. Real estate "sharks" are already active and have promoted the sale of much land which they represent as being situated in a favorable spot for irrigation from water to be impounded by the dam. Much of this land is said by the government to be situated several hundred feet above the level of the proposed dam to be unfit for use even if water were available. To forestall this exploitation of men and land the government has recently issued a timely warning to the effect that it will be at least eighteen months before work on the construction of the dam is actually begun and that no homesteading claims on land under the project will be allowed until its completion which will be about eight years. !his announcement may come as somewhat of a shock to many optimists unacquainted with the actual provisions of the bill, for them it may be said that much depends upon the possibility of reaching a satisfactory solution of the problem of water allocation between California and Arizona. To date such a solution has not been reached and unless Arizona is satisfied it is highly probable that the question will be carried to the courts and long months of litigation ensue. If a satisfactory compromise is reached, the launching of the work will not be· long delayed. Of the ultimate outcome there can be no doubt, and the future seems to hold a very rich promise for the great Southwest. As this subject is approached for study one is somewhat overwhelmed by its many ramifications. The engineering problems alone are of tremendous scope. The legal aspects of the question furnish material for exhaustive study. The political issues tend to claim a greater place than their real merit would seem to justify. While all the different phases of the question are somewhat closely bound together, it has been the purpose of the writer in this study to draw at least a faint line of demarcation and confine it as much as possible to the economic aspects. The Boulder Canyon Project Act proposes a four fold plan of economic development; namely, flood-control, irrigation, power development and domestic water-supply. It is to these features that most attention will be given, together with the historical background of the program. It would be only just at this point to acknowledge the very generous response to calls sent out by the writer for reference material. More than a score of individuals and organizations responded with most gratifying results. Included in these were the governors of the seven states in the Colorado River basin, Senator Hiram W. Johnson and Congressman Philip Swing of California, co-authors of the Swing-Johnson bill; the Chairmen of the Senate and House committees on Irrigation and Reclamation; the Pacific Gas and Electric Company; the Southern California Edison Company; the Boulder Dam Association, and many others.
365

Exploring the Blue Economy Nexus: Government, Industry, and Market’s Perspectives on Seafood

Jingjing Tao (18273118) 29 March 2024 (has links)
<p dir="ltr">Seafood plays a pivotal role in global economies, livelihoods, and nutritional security. However, climate change and global pandemics pose significant threats to seafood harvests, production, supply chains, and marketing channels. The focus of my thesis is to understand the impact of external factors on our seafood resources and explore adaptive strategies in the face of uncertainties. We utilize economics techniques to study human-nature systems by zooming into social elements (government agencies, industry stakeholders, and fish farmers/fishermen) and aquatic resources. The three essays of my thesis delve into this inquiry from the perspectives of government, industry, and market, accordingly.</p><p dir="ltr">The first chapter in my thesis, <i>Climate Change and Snow Crab Harvest - Applying Random Effect Estimators with Instrumental Variable</i>, estimates the snow crab harvest function with unbalanced panel data of eastern Bering Sea snow crab, Canadian snow crab, Japanese snow crab, and Barents Sea snow crab. Specifically, we analyze the relationship between snow crab biomass, stock, and catch. To address the endogeneity of stock in the harvest function, climate change indicators are selected as instrumental variables. We identify that the Arctic Sea ice extent is effective in addressing the endogeneity and the random effects instrumental variable model with error components two stage least squares estimator performs the best to control heterogeneity. We find that a 1% increase in snow crab fishing effort is associated with a 0.42% increase in snow crab harvest, and a 1% increase in snow crab stock causes a 0.98% increase in snow crab harvest. The reported estimates indicate a large stock-harvest elasticity and provide supporting evidence for government fishery agencies to prioritize stock enhancement in policy designs.</p><p dir="ltr">The second chapter, <i>Online Media Sentiment Analysis of Shrimp and Salmon in the United States</i>, employs online media analytics on shrimp and salmon in the US to provide insights into consumer perceptions and potential demand signals for seafood. Search hits and mentions are quantified for top sources, domains, and prevalent terms. In addition, sentiment drivers and sentiment values are identified and calculated using natural language processing tools. The results reveal that the occurrence of peak mentions does not necessarily coincide with the peak of net sentiment, and farmed seafood consistently exhibits lower net sentiments compared to their wild counterparts. Autoregressive modeling is conducted to predict the dynamics of seafood’s net sentiments. The regional analysis demonstrates that public attitudes toward both farmed shrimp and salmon in the East North Central region exhibit a more positive net sentiment, while the New England and Middle Atlantic regions tend to have a lower net sentiment for farmed shrimp and salmon, respectively. The fitted forecast model serves as a supplementary tool for industry stakeholders to quickly respond to future public perceptions. Regional statistics also help the seafood industry tailor business strategies to different regions.</p><p dir="ltr">In the third chapter, <i>Comparative Case Study of Small-Scale Fish Processing for Local Seafood Supply</i><i>,</i> we examine the feasibility of utilizing a shared-use commercial kitchen and on-farm kitchen to support small-scale local fish processing, which helps diversify marketing channels in the US Midwest and supply seafood to local food systems. A case study of each facility type is assessed for economic viability for fish farmers. The financial analysis suggests farmers interested in processing tilapia or rainbow trout from 2,500 lbs to 5,000 lbs per year utilize rental commercial kitchens. A minimum of 15% markup and processing of 10,000 lbs/year tilapia is required to make the on-farm kitchen option more viable. For farmers who process rainbow trout, 10,000 lbs/year with a 10% markup using an on-farm kitchen is a better choice. Factoring in the stochastic variability of raw product prices, rental rates, and set-up costs, we provide simulated ranges for economic metrics including profitability index, payback period, and net present values. The reports of estimated costs, revenues, and breakeven prices, provide fish farmers with suggested selling prices, kitchen choices, and production levels to achieve optimum profits under risks.</p>
366

Solid waste reduction management with special reference to developing countries

Human, Etienne Hugo 30 November 2005 (has links)
Sustainable development and the Triple Bottom Line integrated sustainability concept focus on the choices between the imperatives of economic efficiency, social development and environmental sustainability. Corporate governance is being imposed by stakeholders and corporate social responsibility is indicated as being the most important socio-environmental demand being made on contemporary leaders. The influence of idealism and realism on, and the reasons for failure of, solid waste reduction projects in terms of sustainability is the foundation of the theories postulated in this research. It is the objective of this research to identify the motivational factors, with special reference to developing countries, of social capital, including management processes leadership and people management, that will augment solid waste reduction projects that are lethargic at starting, or deteriorating, to achieve sustainability. The methodology is to review the literature available to identify the augmenting (motivational) factors, and use analytical philosophical and empirical research to test formulated constructs using hypotheses. The criterion for the research sample is to obtain the opinions of environmental specialists in South Africa using a questionnaire. The technique employed is multivariate data analysis to identify the type of interdependent relationships, including cluster and multidimensional scaling analyses. Hypothesis testing, in this research, leads to the conclusion that additional motivational factors are needed to support the economic imperatives to make the process sustainable. `Reality' is statistically significantly different to `idealistic'. The inference is that for solid waste reduction projects to succeed leaders from government and the private sector are required, through the use of legislation and taking into consideration the value of waste, to instil economic incentives. According to this research, personal values and belief systems have little to contribute to the process of sustainability. The outcome of this research provides a strategy-benchmarking-model that leaders can use to target and prioritise their efforts in respect of achieving success with waste projects. The contribution it makes to the knowledge base of the subject and responsible leadership is contained in its summation of the augmenting factors required, their relative importance, and the lessening of the complexity of approach to these projects. / Graduate School of Business Leadership / D.B.L.
367

Solid waste reduction management with special reference to developing countries

Human, Etienne Hugo 30 November 2005 (has links)
Sustainable development and the Triple Bottom Line integrated sustainability concept focus on the choices between the imperatives of economic efficiency, social development and environmental sustainability. Corporate governance is being imposed by stakeholders and corporate social responsibility is indicated as being the most important socio-environmental demand being made on contemporary leaders. The influence of idealism and realism on, and the reasons for failure of, solid waste reduction projects in terms of sustainability is the foundation of the theories postulated in this research. It is the objective of this research to identify the motivational factors, with special reference to developing countries, of social capital, including management processes leadership and people management, that will augment solid waste reduction projects that are lethargic at starting, or deteriorating, to achieve sustainability. The methodology is to review the literature available to identify the augmenting (motivational) factors, and use analytical philosophical and empirical research to test formulated constructs using hypotheses. The criterion for the research sample is to obtain the opinions of environmental specialists in South Africa using a questionnaire. The technique employed is multivariate data analysis to identify the type of interdependent relationships, including cluster and multidimensional scaling analyses. Hypothesis testing, in this research, leads to the conclusion that additional motivational factors are needed to support the economic imperatives to make the process sustainable. `Reality' is statistically significantly different to `idealistic'. The inference is that for solid waste reduction projects to succeed leaders from government and the private sector are required, through the use of legislation and taking into consideration the value of waste, to instil economic incentives. According to this research, personal values and belief systems have little to contribute to the process of sustainability. The outcome of this research provides a strategy-benchmarking-model that leaders can use to target and prioritise their efforts in respect of achieving success with waste projects. The contribution it makes to the knowledge base of the subject and responsible leadership is contained in its summation of the augmenting factors required, their relative importance, and the lessening of the complexity of approach to these projects. / Graduate School of Business Leadership / D.B.L.
368

Factors Influencing Indiana Residents' Level of Interest in Engaging with Purdue University

Ashley E Rice (6615803) 15 May 2019 (has links)
The land-grant university system was founded in the 19th century as a public means to help improve people’s everyday lives. A century and a half later, the challenges that the public faces to live a quality life are constantly changing, creating a need for the land-grant system to respond and adapt to continue to fulfill its mission. While the literature contains a wealth of conceptual papers addressing the role and mission of land-grant universities, relatively few papers could be found that reported empirical data or proposed and tested metrics for public engagement constructs. The current study sought to address this void in the literature through the investigation of factors influencing Indiana residents’ level of interest in engaging with Purdue University. Mail survey methods were used in which up to three contacts were made with adult members of 4,500 Indiana households identified through address-based sampling. Stratified random sampling was employed to ensure adequate rural household participation for other project purposes. Usable responses were received from 1,003 households representing 87 Indiana counties for a total response rate of 26%. <br><div><br> </div><div> A theoretical perspective was developed from Public Sphere Theory and the social science writings of Jurgen Habermas and Alexis de Tocqueville. Descriptive findings revealed some to moderate concerns about community and social issues such as affordable health care, violent crime, pollution and prescription drug abuse. Moderate levels of anomie, or perceived social disconnectedness, were also reported by respondents. Several items tapped respondents’ past levels of interaction with and current perceptions of Purdue University. Nearly a fifth of respondents reported interacting with Purdue University by having visited a website for news or information, followed by interacting with a Purdue University Extension professional. Regarding perceptions of Purdue University, the results of this study revealed relative consensus among respondents that Purdue University makes a positive contribution to the state of Indiana through its educational, research and outreach programs. For a majority of the perceptual items regarding Purdue University, more than one-third of the respondents neither agreed nor disagreed with the statement, suggesting some areas in which the university might improve its reputational standing with Indiana residents in the future. Nearly one-quarter to about half of the respondents indicated interest in topical areas addressed by Purdue Extension programs as well as an interest in engaging with the university. Respondents reported the highest levels of interest in free Extension programs in their local area, followed by the topics of science and technology, health and well-being, and gardening.</div><div><br> </div><div> A predictive model of respondent interest in engaging with Purdue University was developed and tested using binary logistic regression procedures. The model was shown to be of modest utility in accounting for variance in respondent interest in engaging with Purdue University, explaining 12% to 16% of total variance. Past interaction with Purdue University, perceived level of concern for social and community issues, and highest level of education were the strongest predictors in the model.</div><div><br> </div><div> The current research was completed in 2019 as Purdue University celebrated its 150th anniversary. Results and implications of this study provide important insight into current engagement levels, concerns and perceptions of residents within the state of Indiana, whom the university is mandated to serve. One of the study’s primary contributions is the establishment of baseline engagement data on current levels of Indiana residents’ interest in engaging with Purdue University on selected topics. Findings from this study could be of benefit to university administrators, faculty, staff and Extension professionals in assessing and improving future programming and setting strategic priorities. This study also adds to the conceptual and empirical body of literature, which may help inform future public engagement efforts at other land-grant universities. Periodic social science and public opinion research is needed to keep pace with the changing needs and perceptions of Indiana residents. Different data collection modes should be utilized to reach more audience segments and add to the growing knowledge base of public engagement.</div>

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