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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.
171

Modeling Impacts of Land-Use/Land-Cover Change and Variable Precipitation on Hydrology and Water Quality of a Coastal Watershed in Texas

Castillo, Cesar Ricardo 16 December 2013 (has links)
Land use/land cover (LULC) change and variations in precipitation can alter the quantity and quality of freshwater flows. The Mission-Aransas (M-A) estuary depends on inputs of freshwater and material from streams in order to maintain its ecological integrity. Freshwater inflow estimates for the M-A estuary have been established, but no analyses using scenarios of LULC change and precipitation variability have been conducted that inform how freshwater inflows could be impacted. A land change analysis for the M-A region was conducted by classifying two Landsat images for the years 1990 and 2010. A large degree of LULC change occurred within the M-A region during this time; with 27.1% of the land area experiencing LULC change. Furthermore, developed land increased by 44.9%. A SWAT hydrological model was developed to model the quantity and quality of freshwater inflows. SWAT was calibrated at a monthly scale using data from a stream gage. Model evaluations indicated that the model had a good performance rating with a Nash-Sutcliffe model efficiency coefficient (NS) of 0.66 and coefficient of determination (R2) of 0.66 for the calibration period; and an NS of 0.76 and R2 of 0.78 for the validation period. Three LULC change scenarios and three precipitation scenarios were developed to be used in a scenario analysis with the calibrated SWAT model. Each LULC change scenario represents a different amount of developed land (3.4, 3.7, and 4.7% of watershed area). Precipitation data was analyzed to select weather data for each precipitation scenario that each had different amounts of annual precipitation (763, 907, and 996 mm). A scenario analysis was conducted that analyzed how stream/channel flows and loads of sediment, total nitrogen, and total phosphorus were impacted under scenario conditions. A general increase in all output variables was exhibited as the amount of precipitation and developed land increased; with impacts from precipitation variability outweighing impacts from varying amounts of developed land. Furthermore, sediment loads were the variable most impacted by differing amounts of developed land. This study provides information on how LULC and precipitation can influence watershed hydrology that can be used in watershed management for the M-A region.
172

Indiana Jones and the Mysterious Maya: Mapping Performances and Representations Between the Tourist and the Maya in the Mayan Riviera

Batchelor, Brian Unknown Date
No description available.
173

Greening our working lives : the environmental impacts of changing patterns of paid work in the UK and the Netherlands, and implications for working time policy

Pullinger, Martin Iain January 2012 (has links)
Paid working patterns are currently regulated by governments around the world for a range of social and economic reasons: to increase labour supply and skills; to provide a strong tax base to support an ageing population; to help people reconcile work and family life over increasingly diversified life courses; and to be in line with the general principle of the activating, employment led welfare state. Environmental considerations rarely feature in the design or evaluation of working time policy. Nevertheless, various authors working on policies for sustainable development argue that reductions in average paid working time could lead to environmental benefits: as people work less, they in turn earn less, and so consume less, resulting in lower environmental impacts from lower levels of production of products. This thesis takes this argument as its starting point, and synthesises these distinct perspectives on working time and its regulation to address two key questions: what level of environmental benefits could arise from such reductions in paid working time?; and what are the implications for the design of working time policy? The research addresses these questions, taking the case of greenhouse gas emissions, and the UK and the Netherlands in the early 2000s as case studies. Using household expenditure survey data and data on product emissions intensities, the relationship between paid working time and emissions is analysed at both the household and national levels. At the household level, statistically and substantively significant correlations are found between higher levels of paid work and higher levels of consumption and so greenhouse gas emissions. The effects on emissions of hypothetical changes in the working patterns of the national populations are then modelled. The research estimates that meeting current national objectives to increase labour market participation rates would increase national greenhouse gas emissions by 0.6-0.7%, a cost that might be considered acceptable if it also achieves its aims of reducing income poverty, benefit dependency, and social exclusion. Meanwhile, widespread reductions in average working hours and increased use of career breaks, with corresponding reductions in income, would reduce national emissions. The scenarios modelled (a 20% reduction in the working hours of full time workers, and increasing use of 3 month career breaks) lead to reductions of 3-4.5% in national emissions, with the corresponding increases in “leisure” time, reductions in income inequality, and reduced gender imbalances in the distribution of paid work potentially also improving wellbeing, social cohesion, and gender equality in work and care. The results indicate that environmental factors warrant consideration in the design and evaluation of working time policy, and that challenging but achievable levels of working time reduction could contribute a small but significant share to meeting greenhouse gas emissions targets. Policy instruments would need to address a range of values, attitudes and norms around employment and consumption, as well as employer and situational factors, if substantial working time reduction were to be achieved. Reconciling diverse environmental, social and economic goals also requires careful policy design, particularly for certain demographic groups such as the low income, who would need financial and other support to turn rights to reduce working time into functional freedoms that they could utilise.
174

Policy development framework for aviation strategic planning in developing countries

Itani, Nadine M. 02 1900 (has links)
There exists no predefined framework for aviation policy making and development. While aviation policy planning in most developed countries comes as a result of institutional and industry coordination and is embedded within other national policies addressing the welfare and growth of the country, it is found that in many cases in less developed countries (LDCs), aviation policy planning is often influenced by political pressures and the interests of fund donors. The complexity of this situation in the developing countries results in aviation plans that represent stand alone studies and attempt to find solutions to specific problems rather than comprehensive aviation plans which fit well the country‘s competitiveness profile and are properly coordinated with other national policies for achieving medium and long-term objectives. This study provides a three-stage policy development framework for aviation strategic planning based on situational analysis and performance benchmarking practices in order to assemble policy elements and produce a best-fit aviation strategy. The framework builds on study results that indicate an association between air transport sector performance and aviation policy strategies, arguing that it is not sufficient to simply describe performance but also to be able to assess it and understand how policymakers can use strategic planning tools to affect the air transport industry efficiency levels. This can be achieved by recognizing the level of the country‘s stage of development and working on enhancing the policy elements that produce better output and induce more contributions by aviation to the national economic development and connectivity levels. The proposed aviation policy development framework is systematic and continuous. It helps policymakers in LDC to manage uncertainty in complex situations by allowing them to defend, correct and re-examine the policy actions based on a forward thinking approach which incorporates the contingency elements of the policy and tracks the developments that can affect the odds of its success. The framework‘s elements and its flow of process are explained by providing an illustrative example applied to the Hashemite Kingdom of Jordan.
175

The impact of scenarios and personas on requirement elicitation : an experimental study

Arikoglu, Serap 07 February 2011 (has links) (PDF)
La problématique centrale de la thèse est l'évaluation de l'impact de démarches utilisant la formulation de scénarios et de personnages sur les phases d'expression des besoins en conception innovante. La méthodologie de recherche mise en œuvre est une démarche empirique qui s'appuie sur l'analyse de situations de conception. Au cours du doctorat, un protocole expérimental mis en œuvre a été dupliqué trois fois dans des laboratoires partenaires. Cette recherche aboutit à un mémoire de thèse qui présente plusieurs contributions : La première contribution se situe autour de la méthodologie de recherche proposée. Le protocole d'étude empirique mis en place est original, il s'appuie sur l'état de l'art des réflexions de la communauté et sur ces démarches de recherche, et proposes des éléments nouveaux à cette réflexion en conciliant approches quantitatives et qualitatives. La seconde contribution porte sur la caractérisation de l'impact des méthodologies étudiées sur la construction d'une représentation partagée du problème de conception et de la formalisation des exigences de conception. Enfin la troisième contribution porte sur l'analyse des interactions dans les activités de conception étudiées. Les analyses identifient et qualifient les impacts des méthodes étudiées sur le contenu des interactions dans les phases amont de la conception.
176

Strategic repositioning of Safripol in the South African polymer industry / W.A. du Plessis

Du Plessis, Willem Adriaan January 2010 (has links)
Safripol is a South African polymer company producing mainly high density polyethylene and polypropylene for the South African market. Safripol used to be part of a global chemical company Dow Chemicals. Dow Chemical's divested in South Africa in 2006 and Safripol lost all the advantages of being part of a global corporate enterprise. The company is faced with a unique situation in that it is receiving monomer from Sasol, which is also its main competitor in the polymer market. The price of monomer and its low availability is putting pressure on Safripol's product margins, with a negative effect on the company's sustainability. The above was also defined as the research problem that threatens to undermine the company's competitive edge in the polymer market. It was clear from this research study that monomer and specifically propylene was the biggest burning point for Safripol regarding the price and availability thereof. Research into the South African polymer market has shown that Safripol will lose significant market share if the company is not showing additional growth in the market. The research problem is investigated through interviews, monomer availability investigations, plant capacity increasing and potential technology partner's discussions. A specific scenario planning process was also followed to help Safripol identify potential present and future scenarios that the company can investigate. The research problem was addressed by developing a strategy for Safripol to address the research objectives. Recommendations were done regarding the following: 1) Recommendations for additional propylene supply. 2) Recommendations to increase the polypropylene plant capacity. 3) Recommendations with regards to technology partners. 4) Recommendations regarding the scenario planning process. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011. (Mag eers in 2014 gepubliseer word)
177

Beyond the high road : a scenario analysis of the prospects for political stability or instability in South Africa over the period to 2024 / Frans Johannes Cornelius Cronje

Cronje, Frans Johannes Cornelius January 2013 (has links)
Despite the widely hailed success of South Africa’s transition from apartheid to democracy it was apparent by the mid-2000s that beneath the veneer of stability lay a country facing serious social and economic challenges. The employment and labour market participation rates were uniquely low among emerging markets. Protest action against the state had reached levels last encountered in the volatile 1980s and early 1990s. The budget and current account deficits had reached unsustainable levels. By its own admission the government realised that the country was not recording GDP growth rates necessary to make dramatic inroads into poverty, unemployment and inequality levels. A number of analysts and commentators therefore came to question the future stability of South Africa’s political system. Trade unions and some Cabinet ministers routinely described unemployment as a “ticking time bomb”. The Chairman of the Institute of International Affairs wrote in Business Day that he could predict when South Africa’s “Tunisia Day” would arrive. The respected Economist newspaper ran a front page feature on what it called South Africa’s “downhill slide”. Former President FW de Klerk warned that South Africa was approaching a precipice. Clem Sunter, South Africa’s most renowned scenario planner, upped his prospects that South Africa may become a failed state. Global ratings agencies downgraded South Africa citing the fear that government policy could not meet popular demands. Amidst such speculation it is vitally important that the prospects for instability be investigated and determined, not via opinion or speculation, but rather against a sound body of theory. This task is complicated by the fact that the feared instability may only occur at a point in the future. The theory must therefore be applied via a methodology capable of overcoming the weak track record of political science in accurately anticipating major shifts in political systems. This problem statement will be addressed by showing that complex systems theory holds the key to a series of units of analysis via which the stability or instability of any political system can be objectively determined, compared to any other political system, and tracked over time. Secondly that there are scenario planning methodologies that can overcome the uncertainty inherent in the futures of all complex systems and thereby the poor track record that political scientists have in anticipating dramatic future changes in the systems they study. When combined into a single complex systems/scenario model, these theoretical and methodological points of departure will allow the long term prospects for stability or instability of any political system to be accurately and objectively determined. / PhD (Development and Management) North-West University, Potchefstroom Campus, 2013
178

Strategic repositioning of Safripol in the South African polymer industry / W.A. du Plessis

Du Plessis, Willem Adriaan January 2010 (has links)
Safripol is a South African polymer company producing mainly high density polyethylene and polypropylene for the South African market. Safripol used to be part of a global chemical company Dow Chemicals. Dow Chemical's divested in South Africa in 2006 and Safripol lost all the advantages of being part of a global corporate enterprise. The company is faced with a unique situation in that it is receiving monomer from Sasol, which is also its main competitor in the polymer market. The price of monomer and its low availability is putting pressure on Safripol's product margins, with a negative effect on the company's sustainability. The above was also defined as the research problem that threatens to undermine the company's competitive edge in the polymer market. It was clear from this research study that monomer and specifically propylene was the biggest burning point for Safripol regarding the price and availability thereof. Research into the South African polymer market has shown that Safripol will lose significant market share if the company is not showing additional growth in the market. The research problem is investigated through interviews, monomer availability investigations, plant capacity increasing and potential technology partner's discussions. A specific scenario planning process was also followed to help Safripol identify potential present and future scenarios that the company can investigate. The research problem was addressed by developing a strategy for Safripol to address the research objectives. Recommendations were done regarding the following: 1) Recommendations for additional propylene supply. 2) Recommendations to increase the polypropylene plant capacity. 3) Recommendations with regards to technology partners. 4) Recommendations regarding the scenario planning process. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2011. (Mag eers in 2014 gepubliseer word)
179

Beyond the high road : a scenario analysis of the prospects for political stability or instability in South Africa over the period to 2024 / Frans Johannes Cornelius Cronje

Cronje, Frans Johannes Cornelius January 2013 (has links)
Despite the widely hailed success of South Africa’s transition from apartheid to democracy it was apparent by the mid-2000s that beneath the veneer of stability lay a country facing serious social and economic challenges. The employment and labour market participation rates were uniquely low among emerging markets. Protest action against the state had reached levels last encountered in the volatile 1980s and early 1990s. The budget and current account deficits had reached unsustainable levels. By its own admission the government realised that the country was not recording GDP growth rates necessary to make dramatic inroads into poverty, unemployment and inequality levels. A number of analysts and commentators therefore came to question the future stability of South Africa’s political system. Trade unions and some Cabinet ministers routinely described unemployment as a “ticking time bomb”. The Chairman of the Institute of International Affairs wrote in Business Day that he could predict when South Africa’s “Tunisia Day” would arrive. The respected Economist newspaper ran a front page feature on what it called South Africa’s “downhill slide”. Former President FW de Klerk warned that South Africa was approaching a precipice. Clem Sunter, South Africa’s most renowned scenario planner, upped his prospects that South Africa may become a failed state. Global ratings agencies downgraded South Africa citing the fear that government policy could not meet popular demands. Amidst such speculation it is vitally important that the prospects for instability be investigated and determined, not via opinion or speculation, but rather against a sound body of theory. This task is complicated by the fact that the feared instability may only occur at a point in the future. The theory must therefore be applied via a methodology capable of overcoming the weak track record of political science in accurately anticipating major shifts in political systems. This problem statement will be addressed by showing that complex systems theory holds the key to a series of units of analysis via which the stability or instability of any political system can be objectively determined, compared to any other political system, and tracked over time. Secondly that there are scenario planning methodologies that can overcome the uncertainty inherent in the futures of all complex systems and thereby the poor track record that political scientists have in anticipating dramatic future changes in the systems they study. When combined into a single complex systems/scenario model, these theoretical and methodological points of departure will allow the long term prospects for stability or instability of any political system to be accurately and objectively determined. / PhD (Development and Management) North-West University, Potchefstroom Campus, 2013
180

Forest health based scenario building as an accessible tool for climate change management in Bruce Peninsula National Park

Moores, Kelly January 2014 (has links)
The global climate is changing; there are many predictions about the ecological impacts, and even more uncertainty. Predicted ecological impacts include northward shifting biomes, invasive species, decoupling of biotic interactions, all of which are threats to the ecological integrity (EI) of Canada’s National Parks System. To maintain EI, parks must be managed for resilience with climate change in mind. Lack of human and financial resources are restrictions to managing for climate change, challenges exacerbated by government cutbacks in 2012. To overcome these restrictions a tool for informing management in a climate was designed using an existing research program and management based scenario building at the case study location of Bruce Peninsula National Park (BPNP). The tool designed for informing management is called Scenario Building, which accounts for uncertainty and focuses on the essential drivers of the local ecological community. Diversity and health in the forest community are essential drivers in the BPNP ecosystem with interactions at many tropic levels so the forest health research program was selected as the basis for scenarios. Results show a range of tree species that require a variety of soil and moisture regimes. Understanding the ecology of the keystone forest species allows for understanding of how they may reacted to predicted climate changes. Regional climate predictions based on the A2 and B1 primary climate scenarios of the IPCC were integrated with the forest health data, and two levels management option- passive and active to develop 4 scenarios that can inform management of the park. Passive and active management were defined by the number of dollars spent on active management. The 4 scenarios developed were: Scenario 1 B1 Passive Management - Status Quo, Scenario 2 B1 Active Management - Regional Resilience, Scenario 3 A2 Passive Management - Evolving Forests, Scenario 4 A2 Active Management- Anticipatory Restoration. A set of scenarios allows managers to set a management trajectory balances resilience and EI with economic viability in the face of climate change. Analysis of the BPNP scenario suite tell us that BPNP is one park that is in a good position to be able to adapt to a changing climate without major risk to EI, however significant steps can be taken to minimize losses or even improve EI by anticipating needs and investing in active management.

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