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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.
1

Aspects of compliance in common pool resources

Navrouzoglou, Polmia January 2013 (has links)
There is an inherent externality across generations in environmental economics: extensive use of the natural environment by the current generation may affect the welfare of future generations. The use of the natural environment includes not only the reduction of resource stocks, like fossil fuels and rain forests, but also the accumulation of pollution stocks. Efficient policy directed to changing the resource extraction and pollution profiles needs to take into account the internal and external forces driving resource markets and their impacts on the aggregate economy. But compliance to these measures is not warranted unless there is an implicit or explicit (or both) enforcement mechanism in place. The traditional approach to discuss the optimal centralized exploitation policy has been to assume that individuals are narrowly self-interested. Empirical evidence suggests, however, that individuals’ characteristics (heterogeneity) play a key role in resolving collective action problems. Chapter 1 develops a dynamic model of common renewable resources management where a centralized mechanism works together with a self-enforcement one—guided by social norms—to form an institution. The results provide a theoretical explanation for the evidence of why economies with abundance of resource stocks may not improve their institutions while others with scarcity of resource stocks may do. Institutional context is likely to determine the impact of trade liberalization on welfare and resource conservation. Chapter 2 follows the recent literature on trade and endogenously determined institution to investigate this link further. It combines a common renewable resource model with elements of moral hazard and identifies conditions under which countries escape the ‘tragedy of commons’. It shows that country characteristics and technologies in alternative sources of income determine how centralized institutions perform and whether there are gains 2 from trade. A key issue underlying global environmental protection is that international trade puts downward pressure on countries’ environmental standards. Chapter 3 explores—within an imperfectly competitive environment—the welfare implications of taxation when production causes environmental pollution (a global public bad) under two tax principles, ‘destination’ and ‘origin’. It shows that the noncooperative environmental tax policy does not always give rise to taxes that are too low in equilibrium, from welfare point of view, and identifies conditions under which the presence of a global public bad tilts the welfare comparison towards, interestingly, either tax principle.
2

On the validity of contingent valuation : a psychological perspective

Svedsater, Henrik January 2001 (has links)
This thesis addresses the validity of the Contingent Valuation (CV) methodology. Unlike conventional economic approaches, this is based on stated preferences in hypothetical market scenarios and is used in attempts to estimate economic benefits of non-marketed public goods, most notably natural resources. However, the methodology is not without controversy and many researchers question people's ability to provide valid economic values for environmental amenities in these contexts. The present research applies a psychological perspective to this area, and hence adopts a different approach than mainstream work in the field that has traditionally been more concerned with methodological procedures and how well data fit with economic theory. The first section presents the rationale of the CV methodology and reviews a number of conceptual problems and empirical anomalies that have been demonstrated across studies and contexts. It sets these within a theoretical framework that, it is envisaged, will contribute to our understanding of people's responses to CV questions. In the empirical section a number of hypotheses derived from this theorising are tested. The results indicate that statements of economic value, particularly for complex amenities, are unresponsive to the magnitude or importance of the resource being valued. Some people also tend to provide, often seemingly 'reasonable' responses, irrespective of their ambivalence toward the valuation procedure. It is further demonstrated that there is a high degree of uncertainty involved in reported economic value, indicating that CV responses are quite imprecise representations of underlying preferences. Finally, hypothetical willingness to pay are shown to be a poor indicator of real economic commitments, resulting partly from the self-image people strive to achieve in these contexts, particularly when choices appear inconsequential. The major conclusions of the thesis are that responses in CV studies to a large extent are motivated by expressive rather than instrumental considerations, that respondents' interpretations of the valuation task do not always correspond with the intention by the researcher, and that situational and contextual factors have important implications for the assessment of environmental benefits.
3

Complexing capacities and conditional stability constants of zinc-organic complexes in interstitial and estuarine waters

Dharmvanij, S. January 1983 (has links)
No description available.
4

The development, application and evaluation of participatory geographic information system methodologies for improved environmental decision making

Cinderby, S. January 2014 (has links)
This thesis reflects upon almost two-decades of my continued use, reflection and development of methods utilising maps as discussion tools allowing different groups views on environmental issues and development options to be more clearly understood. The overall aim of this improved participation and communication has been the identification and implementation of alternative (more democratic and informed from a wider evidence base) development choices. This improved understanding is intended to result in more sustainable outcomes from decision making processes at a variety of appropriate and relevant management scales. The thesis is comprised of seven published papers exploring the development and application of participatory geographic information system (PGIS) approaches in the context of their utility and effectiveness in improving environmental management decision making processes and outcomes. Within this overall commonality the papers can be differentiated into four themes. Firstly, four papers assess the development of focus group based PGIS approaches to improve shared understanding and public involvement in natural resource management and pollution control in the UK and South African contexts. The second theme explored in two papers describes the evolution of mapping engagement and mixed methods approaches to widen participation to, often, disenfranchised groups or to facilitate the inclusion of local perspectives in contested or sensitive issues both from the UK. The third theme investigated in the penultimate paper is the potential for using PGIS derived data as a framework to nest different spatial and experiential scales of knowledge within a decision making process. The fourth theme from the final paper involves widening PGIS approaches to include elements of other social research methods, in this example vignettes, to stimulate the mapping process and outputs.
5

2MW : the wood fuel energy systems conceptual design metamodel : a novel approach to participatory design, contextualised to the case of Mozambique

de Albuquerque Martins, Ricardo Jorge January 2014 (has links)
This research endorsed, built and tested a metamodel, the 2MW: a novel design tool to assist all knowledgeable actors on wood fuel (e.g. firewood users, charcoal makers, policy makers) in the participatory conceptual design of wood fuel energy systems (WES), i.e., in the process of co-conception, co-specification and co-modelling of WES. The 2MW relevance is twofold. First the 2MW fulfils a gap in the portfolio of design tools for WES. Second the conceptual design of WES is a fundamental concern since billions of people in 'Developing Countries' (DCs) rely heavily on WES for energy needs; and the WES are mutually embedded within global priorities, including deforestation and poverty. In the context of this work, Mozambique, over 70% of the population rely exclusively on WES, and the charcoal business has an estimated value of 520million US$/year. Despite the documented drawbacks, the few available or applicable WES design tools simplify the WES complexity into a set of parameters to be optimised/simulated into normative and prescriptive tools, mostly computer based and designed exclusively by/for experts to facilitate the analysis/decision on the transition towards what are considered to be more sustainable, efficient and modern solutions. The 2MW represents a fundamental departure from this energy transitions paradigm in a number of interwoven aspects. Based on systems and design thinking the 2MW embraces WES as a complex design problem favouring full participation, reflective practice, learning, sensemaking and suitability to the intended users and contexts. Therefore, the 2MW is not a parametric simulation model, but a design metamodel made of 13 design elements, which make explicit what WES actors think about when they think about WES design. The 2MW is non-computer based and visually presented as 13 boxes drawn on paper or the ground suitable for low literacy and resource limitations in DCs. The 13 design elements have been derived through ontological analysis of relevant literature and semi-structured interviews with 131 pertinent actors in the WES in Mozambique and elsewhere and the 2MW has been extensively and intensively tested in 7 participatory design workshops conducted in rural and urban Mozambique involving over 50 persons covering a wide range of WES perspectives. The results consistently confirmed: 1) the 13 design elements are meaningful, sufficient and necessary intuitively easy to understand and interact, with 2) the 2MW is an effective, efficient, explicit and interactive common ground/language facilitating the debate, knowledge sharing, sensemaking and learning on participants' terms (by-passing predefined normative and concepts); 3) the WES conceptual designs produced with the 2MW is creative, comprehensive, easily shared and meaningful. Finally, as an efficient and effective tool for WES participatory conceptual design the 2MW is potentially useful to complement other available design tools on wider and more integrated WES design, analysis and implementation.
6

Are all energy resources created equal? : a comparative analysis of the dynamics of resources for the energy system

Speirs, Jamie January 2014 (has links)
There is a longstanding debate about the future availability of energy resources, and a significant literature has developed around the issues of oil availability in particular. More recently, the availability of lesser-known critical metals, such as lithium and indium, has been called into question. These metals are key components in low-carbon energy technologies and a new evidence base that questions their future availability is emerging. Much of this research applies methods and techniques also applied to the analysis of oil resources, with the implicit assumption that these resources are in some way analogous. However, although there are similarities, there are also structural differences and the appropriateness of the assumed analogy has not been sufficiently tested. This thesis explores the similarities and differences in the structure of the oil, lithium and indium resource systems, examining the likely response of these systems to availability constraints and testing the appropriateness of this assumed analogy. The systems that define the market for resources are dynamically complex and involve a number of different interlinked variables. The way in which these resource systems respond to changes in surrounding conditions arises from the structure of these variables and their linkages. However, much of the existing analysis of critical metals relies on simplistic assumptions regarding the structure and function of these systems. To address this knowledge gap, this thesis first presents case studies of the three resource systems. The case studies are then used to develop three system dynamics models. This thesis finds that, while there are many similarities in the structure of the three resource systems modelled, the differences between them have a significant impact on their dynamic system behaviour. Analysis which overlooks these differences is likely to draw inaccurate conclusions. In particular, the resilience of metals to periods of constrained availability is potentially greater than that of oil if metal recycling is taken into account. However, metals recovered as by-products are potentially limited in their ability to resist constrained availability.
7

Metapopulation modelling and spatial analysis for HEG technology in the control of malaria

Dickens, Borame January 2014 (has links)
The success of any vector control strategy can be enhanced by onsite analysis and investigation. Combatting malaria, a global disease carried by the vector Anopheles gambiae, has led to the development of novel genetic technologies such as the use of HEG; homing endonuclease genes. This thesis explored the age and stage elements of the vector, building upon current biological understanding and using fitting algorithms with metapopulation matrices to create cohort orientated survival and transition. The environmental forces were analysed alongside this with emphasis on sub-model creation and tool design, employing an array of methods from RBF to satellite classification to couple the local environment and vector. When added, the four potential genetic strategies all demonstrated the ability to suppress a wild type population and even eradicate it, although reinvasion and hotspot population phenomena were reoccurring observations. The movement of the vector was an important factor in control efficiency, which was investigated as a series of different assumptions using wind driven movement and host attraction. Lastly, practical factors such as monitoring and resource distribution within a control project were assessed, which required routing solutions and landscape trapping assessments. This was explored within a framework of Mark-Release-Recapture experiment design that could provide critical information for efficient HEG release strategies.
8

The role of transmission networks in the evolution of a low carbon electricity system in the UK

Hughes, Nicholas January 2014 (has links)
The UK's commitments to addressing climate change require a radical restructuring of the electricity sector. This thesis examines what role the electricity transmission networks could play in this transformation. In order to examine the possible role of policy making within a socio-technical system under conditions of long-term uncertainty, a novel scenario method is developed which accounts for political values, actor dynamics and technological networks. The approach is used to examine possible pathways for the electricity transmission network within alternative policy value-sets, which are defined by the level of locational signal provided to generators in respect of their network usage, and the degree of anticipatory or strategic planning involved in network policy. The scenarios emphasise the importance of a locational signal which acts at the operational timescale as well as the investment timescale. They also suggest a role for strategic coordination, particularly to join up planning across onshore, offshore and interconnector regimes. However, due to the range of possible generation and network configurations the scenarios span, they do not support the idea of a central design authority working to a single network blueprint. Specific policy recommendations aim to incorporate these suggestions within the grain of the existing policy trajectory and its prevailing value system. The two principle policy recommendations are therefore, the inclusion of a locational signal within the BSUoS charge in order to better reflect network usage at the operational timescale, and the establishment of an independent body with a remit to identify and contribute needs cases for cross-regime strategic coordination opportunities. The latter recommendation could be achieved with some adaption and clarification of the remit of the ENSG.
9

The limits of bioenergy : a complex systems approach to land use dynamics and constraints

Strapasson, Alexandre Betinardi January 2015 (has links)
This thesis aims to use a novel methodology to obtain an understanding of the potential limits of bioenergy by using a complex systems approach for assessing land use dynamics and constraints. Although bioenergy is classified as a renewable energy source, land is a finite resource and its expansion limited. The anthropogenic demands on land result from a combination of multiple provisioning services. These include global food consumption, dietary preference, crop and livestock yields, land use integration, wastes and residues, and bioenergy yields and forms, as well as the allocation of surplus land for forestry and energy crops, and the potential role of negative emission technologies. Thus, bioenergy is just one part of a complex land-use system. The general hypothesis is that there are fundamental limits to the overall scale and rate of the sustainable expansion of bioenergy, which can be assessed by means of combinations of empirical data, mapping tools and complex systems models. To this end, a novel methodological approach is proposed, which is based on a combination of two original models. The first one is termed the Global Calculator Land Use Change Model (GCLUC), developed as part of the Global Calculator Project, in which land is freely allocated worldwide and food security is assumed a priority. The second considers land for dedicated energy crops as a delimited reserve, by integrating Hubbert’s curve principles (originally proposed for peak oil assessments) in agro-ecological zoning schemes (as recently done for sugarcane ethanol in Brazil), resulting in a new model here termed green-Hubbert. The results show ranges of bioenergy potentials and expansion rates in the context of different land use futures. The potential public policies necessary to support sustainable bioenergy are also discussed. Finally, the conclusions show that, indeed, there are fundamental limits to bioenergy, and these limits are dynamic over time.
10

Conceiving a systemic approach to implement solar energy technology : the case of Israel

Luvchik, Avi January 2015 (has links)
Population growth, lifestyle and income changes as well as urbanisation are powerful driving forces behind increasing demand for energy. Since 1900, world population has more than quadrupled, real income has grown by a factor of 25, and primary energy consumption has risen by a factor of 22.5. The joint phenomenon of urban and economic growth is particularly relevant in Israel where 76% of the population lives in cities and Israel economic growth rate stood at 5.4% in 2010, a relatively high value compared to most of the OECD countries. As a consequence, total green House Gas (GHG) emissions originated from the use fossil fuels in Israel are expected to rise sharply in 2030. The promotion of renewable energy, particularly solar is a way to deal with predicted rising emissions as well as addressing energy security and increase of oil price that afflict the Middle East region. Worldwide, solar cell electricity generation market has grown dramatically, both in terms of electricity generation and market size. A paradox that this study addresses is that while Israel has developed and exported advanced solar technology, it is among the last countries that actual use this type of technology for self consumption. For most of its history, Israel has been an energy-poor state, relying almost completely on imported fossil fuels to meet its energy needs. However, the Israeli energetic independence has been changed dramatically in 2009 when two large fields (nearly 3.1 Trillion Cubic Feet) of natural gas were discovered in the Mediterranean Sea 60 km off the Israeli coast line. These discoveries have changed the energy market in Israel, bringing the decision makers to rethink about electricity production by renewable energy sources. The approaches developed in this thesis aims to achieve two main goals. To find electricity capacity can be generated by solar technologies based on atmospheric parameters and to find the optimal government incentive for renewable energy to encourage private investors to invest in PV solar systems and thus to meet the government goals of greenhouse gas reduction. To tackle these two main goals of the research, two mathematical approaches and decision-making models were developed. One model -Technical Environmental and Atmospheric (TEA Model) and optimises the application and selection of solar energy technologies in Israel. TEA model taking into accounts mainly atmospheric, demand and environmental parameters. The model provides quantitative and qualitative formulations to energy production capacity, costs, environmental impact and future electricity demand. The second model (policy model) designed to optimise the level of Feed in Tariff (FIT) by using a linear program and a Monte- Carlo Simulation. The innovation of the study is that the decision-making model takes into account factors that had not been considered together before but could have a decisive influence on the uptake of the right solar energy technology. This research found that the annual average energy output by PV system in Israel is 1735kWh=kWp (+/- 10%) and the annual average of performance ratio is 82.3%. In regards to atmospheric pollution, it was found that the increasing of air pollution causes to decrease of electricity generation by more then 10% a year. In respects to the policy analysis it was found the optimal FIT should be 0.15 $/kWh compared to 0.165 $/kWh which was paid in 2015.

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