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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.
801

Origin of the circular silverpit structure, UK North Sea : meteorite impact or salt withdrawal?

Conway, Zana Kate January 2007 (has links)
The origin of the Silverpit structure, UK North Sea has been contested since its discovery on seismic data in 2002. The Silverpit structure consists of a 3 - 4km central zone of deformation, which includes a conical uplift. This is surrounded by a series of ring faults up to a maximum diameter of 20km. Meteorite impact, evaporite withdrawal, pull-apart basin tectonics and halokinesis tectonics have all been suggested as possible origins. This thesis uses a multi-discipline approach to test these hypotheses and determine with certainty the origin of the Silverpit structure. Seismic interpretation of the Silverpit structure has highlighted that deformation in the central deformation zone and beneath the structure is comparable with other meteorite craters. However, the ring faults are comparable with other structures formed by regional evaporite dissolution and movement. Seismic interpretation on a regional, 3500km2 scale proved that the structure is unique and that salt movement was taking place at the same time as the Silverpit structure was created. Unusual diagenesis in the chalk beneath the Silverpit structure was identified as a result of the presence of both unusual geophysical and geochemical signatures. An anomalous sonic log response is attributed to a significantly decreased porosity at the base of the chalk unit. Anomalously negative stable oxygen isotopes were also found in the chalk beneath the structure. Unusually elevated heat flow is the likely cause of these irregularities. The evidence presented in this thesis leads to the conclusion that the origin of the Silverpit structure is in fact two-phase. Meteorite impact has lead to the formation of the central zone of deformation and conical uplift. It has also influenced the diagenesis of the chalk beneath the crater and created a more brittle chalk unit. Regional salt withdrawal is responsible for the formation of the ring faults, which have only formed in the meteorite impact induced brittle chalk. In simple terms, a meteorite impact formed the 3km crater and then salt withdrawal produced the circular rings during several million years after the impact.
802

Exploring and assessing social research impact : a case study of a research partnership's impacts on policy and practice

Morton, Sarah Catherine January 2012 (has links)
There is increasing emphasis on the outcomes of research in terms of its impact on wider society. However in the social sciences the ways in which research is taken up and used, discussed, shared and applied in different policy, practice and wider settings is complex. This thesis set out to investigate the ways in which social research was used by various non-academic actors, and to explore what impact it had in order to develop methods for understanding and assessing impact. The research investigated what research impact is, how it occurs, and how it might be assessed. The research was in two phases: firstly, a case study of a research partnership between a research centre and a voluntary organisation; and, secondly, the development and seeking feedback on a framework to assess impact. The care study employed two main approaches: forward-tracking - from research to policy and/or practice - and backward tracking - from policy back to research. Both phases were conducted through a practitioner-research approach, bringing experience of working with the projects involved into the heart of the research model. The study found many ways the research from the partnership had been used in different sectors by different actors. Impacts from the research were harder to identify. In cases where there were clear impacts, the actors involved had adapted research to fit the context for research use in order to create impact. Research users continued to draw on the research for many years after publication, creating further impact as new policy or practice agendas arose. The framework used a 'pathways to impact' model to develop a theory-based approach to assessing impact and to create categories for data collection. The ways in which research might impact on policy and practice are many and cannot be easily predicted. Concepts from complexity theory, particularly a focus on relationships, an understanding of context and the concept of emergence have been useful in framing the picture of impact generated from this research. Any assessment of impact from social research needs to acknowledge that many actors are involved in the process of research being taken up and used, and impact cannot be achieved from the supply side alone. Partnership research, between an academic and voluntary sector organisation, facilitated the use and impact of the research in many ways. The thesis reconceptualises ideas about how research impacts on society, suggesting the concept of 'contribution' is more accurate and useful than attribution. It also adds to the body of empirical work on the processes of impact, and in particular of the role of research partnerships in increasing impact. It suggests that process-based approaches to assessing impact that acknowledge complexity may be fruitful in developing impact assessment methodology.
803

Effects of Sport-Related Concussion and Pre-Injury Neuropsychological Functioning on Academic Outcomes

Colllins, Christina Lynn January 2016 (has links)
While substantial literature exists regarding the neurocognitive sequelae of concussion and return to play determinations for student-athletes who have suffered a concussion, there is a paucity of research that has conceptualized the impact of concussion on common academic outcomes. This study examined these topics in an attempt to evaluate the impact of concussion on GPA and school attendance, the association of preinjury neurocognitive performance to changes in academic achievement following a concussion, as well as the relationship between baseline neurocognitive performance and academic outcomes. The change in monthly assignment GPA and attendance were analyzed for three comparison groups (concussion, other sport-related injuries, control) regarding their differences pre and post injury. Second, whether a student-athlete's performance on a computerized baseline neuropsychological assessment (ImPACT) moderated the change in monthly assignment GPA for a group of concussed student-athletes identified as either short recovery or long recovery was investigated. Lastly, the association between baseline ImPACT scores and cumulative GPA/standardized achievement measures was examined for the entire group of student- athletes. Results of this study indicated no systematic differences between comparison groups (concussion, control, and injury) with the change in pre and post injury monthly assignment GPA and daily attendance rates, although academic declines were evident among all student-athletes. Further analysis revealed that more athletes who experienced concussions evidenced a significant drop in GPA (> .5) than would be expected by chance. Contrary to expectations, baseline ImPACT assessment scores did not moderate the degree of academic decline for concussed student-athletes within the short or long recovery groups. Finally, baseline ImPACT composite scores were significantly related to general academic achievement outcomes. Specifically, the ImPACT Visual Memory, Visual Motor and Reaction Time Composite scores significantly predicted GPA. Standardized academic achievement scores as measured by the Arizona Instrument to Measure Standards (math, reading, writing and science) were all significantly predicted by the baseline ImPACT Visual Motor Composite score. This study highlights the risk factors that may lead to diminished academic performance for student-athletes and the pre-injury neurocognitive variables measured by ImPACT that predict academic performance for student-athletes.
804

Investing in photovoltaics in Jämtland : Environmental concern? Or profitability push

van der Kraan, Bram January 2016 (has links)
The Regional Council of Jämtland has a goal to increase the export of renewable energy and with that reduce the total greenhouse gas (GHG) emissions. One of the measures used to reach this goal is to give subsidies and tax reductions for investments in photovoltaics. Photovoltaics are generally perceived as “good for the environment” and give a “good image” to companies. They are marketed as interesting for private persons and farmers from a profitability point of view. Sweden has an electricity mix with average CO2 emissions of 20-30 g/kWh. Compared to other countries in Europe this is very low. The CO2 emissions of photovoltaics during their lifetime are 46 g/kWh according to the International Panel on Climate Change (IPCC). Taking this in consideration it can be concluded that photovoltaics actually increase GHG emissions as they have higher emissions of CO2 than the average in Sweden. When the decision to invest in photovoltaics is made with profitability as a main reason, it is debatable if the subsidies and tax reductions are needed. When the decision to invest in photovoltaics is made with environmental concern as a main reason, the subsidies might be given to other environmental technologies that are better from a climate perspective. Considering this, the push for profitability of photovoltaics can be seen as just another increase in consumption.
805

Would you like your receipt? : Sustainability perspectives of consumer paper receipts

Sarenmalm, Isabel January 2016 (has links)
This report researches and analyses the sustainability perspectives of paper receipts, focusing on the economical, environmental and social aspects using a qualitative research method and by simultaneously drawing inspiration from the Sustainability Impact Assessment (SIA) model. The result section is conducted by using a literature review where a combination of previously used sources within my masters program is analysed and by reviewing articles and statistics in the search engine at the Uppsala University e-library database. The overall research purpose, to assess the sustainability of consumer receipts, is achieved by using the concept of sustainable development as the theoretical framework. This report suggests that there are some sustainability concerns with the current consumption of the traditional paper receipt, mainly in the context of environmental and social considerations. Three different alternatives to the traditional paper receipt are furthermore discussed as examples of potential routes forward. Two of the alternatives, electronic receipts and introducing a charge on paper receipts, are arguably the two most sustainable alternatives to regular paper receipts. The third alternative cannot be perceived as equally sustainable since “BPA/Bisphenol-free” receipts contain other chemicals equivalently hazardous to humans and the environment.
806

A critical investigation of the impact of internal family migration on the city of Benghazi in Libya

Saad, M. January 2011 (has links)
During the last fifty years the city of Benghazi in Libya has attracted huge streams of migrants from villages and small towns. This is due to the pull factors of jobs and social services in the city and to the push factors associated with the neglect of villages and small towns. This resulted in the city quickly increasing in size, leading to rapid population growth, culminating in many economic, social and demographic problems. However, little is known about Libyan migration especially in relation to the challenges posed by internal migration. Therefore, there is a need to examine the phenomena of internal migration and its effect on Benghazi, in order to provide planners and policy makers with up-to-date and relevant information to help them make appropriate decisions. The key aim of this study was to determine and critically evaluate the impact of internal migration on Benghazi using an interpretive approach. This was achieved by combining quantitative and qualitative methods. The empirical core of this thesis is based on field work data, including questionnaire interviews with 150 heads of household who had migrated to Benghazi; supplemented by 10 in-depth narrative studies with selected families; and semi structured interviews with key informants (policy makers) to investigate Government policy and the economic, social and demographic impact of internal migration on the city of Benghazi. The starting point of the theoretical basis of this study is based on theories developed by Ravenstein, Lee and Sjaastad. The research shows that there has been a high rate of migration flow to Benghazi over the last fifty years, and that the economic elements (job opportunities, higher incomes and more regular work) are the most important motives for migrating, in addition to social factors namely attending education and having access to health services. The research found that migration to Benghazi involved a bulk exodus of the whole family unit to take advantage of a better lifestyle in Benghazi. The thesis further reveals that these family streams of migrants have affected the social, economic and demographic situation of Benghazi. Despite the Libyan Government seeking to reduce streams of internal migrants, some of these policies have worked, others have not. There is thus difference between what was planned and what has actually been achieved on the ground, demonstrating the need for research such as this.
807

Streamlined interconnection analysis of distributed PV using advanced simulation methods

Reno, Matthew J. 27 May 2016 (has links)
With the penetration of PV on the distribution system continually increasing, new advanced simulation methods are necessary to model the potential technical impacts of PV to the equipment and operation of the distribution system. With distributed PV, a timeseries analysis approach is necessary to more fully capture the time-varying nature of solar energy and the interaction with distribution system operations. The objective of the research is to streamline the PV interconnection process by providing more accurate methods that require less time for both the PV interconnection screening criteria and the PV interconnection impact study process. To improve the computational speed of timeseries simulations, an equivalent circuit reduction method is developed to simplify the circuit to a reduced-order model. The reduced circuit is equivalent during timeseries simulations, but it solves in a fraction of the time. The algorithm works with unbalanced multi-phase complex distribution system models, and it is shown to have high accuracy when validated against the full feeder models. An advanced PV hosting capacity simulation tool is developed and used to quantify system impacts for many PV interconnection scenarios, configurations, and locations, which can be generalized to develop improved future interconnection screening criteria. The advanced tools quantify location-specific impacts and the locational hosting capacity of potential PV interconnection locations on the feeder, including PV impact signatures and zones. A set of 50 different real distribution systems is analyzed in detail to demonstrate the range of scenarios and impacts that can occur depending on the feeder characteristics and topology. Specific methods are developed for time-series analysis, faster simulation times, distribution system equivalent circuit reduction, and PV hosting capacity analysis. The advancements presented in this thesis assist in streamlining PV interconnection studies with faster interconnection analysis times and more accurate screening criteria.
808

Performance Audits : A study of the factors affecting audit impact in Sweden

Persson, Elin, Näsström, Milla January 2016 (has links)
There have been uncertainties to what a performance audit generates, as audit impact have an inherent causality problem. Prior studies present several factors that affect perceived audit impact, but the generalizability is low and not applicable in a Swedish context, thus this thesis contributes to the development of the existing knowledge by investigating audit impact. This thesis consists of a sample of three performance audits which are investigated through a mix methods approach with a total 23 interviews and multiple public documents, analyzed with earlier studies and theories as a benchmark. The findings indicate that audit impact is complex where several factors affect audit impact, this thesis indicated that usefulness and quality of the performance audit are the main factors that affects perceived audit impact. There are also additional effects by the performance audit that fall outside of the audit impact definition. Due to the small sample size and the fact that performance audits often are regulated by local laws one must be careful in what context these findings are solely applied in another context.
809

A benchmark for impact assessment of affordable housing

Okehielem, Nelson January 2011 (has links)
There is a growing recognition in the built environment for the significance of benchmarking. It is recognized as a key driver for measuring success criteria in the built environment sector. In spite of the huge application of this technique to the sector and other sectors, very little is known of it in affordable housing sub-sector and where it has been used, components of housing quality were not holistically considered. This study considers this identified deficiency in developing a benchmark for assessing affordable housing quality impact factors. As part of this study, samples of 4 affordable Housing projects were examined. Two each were originally selected from under 5 categories of ‘operational quality standards’ within United Kingdom. Samples of 10 projects were extracted from a total of 80 identified UK affordable housing projects. Investigative study was conducted on these projects showing varying impact factors and constituent parameters responsible for their quality. Identified impact criteria found on these projects were mapped against a unifying set standard and weighted with ‘relative importance index’. Adopting quality function deployment (QFD) technique, a quality matrix was developed from these quality standards groupings with their impact factors. An affordable housing quality benchmark and a relative toolkit evolved from resultant quality matrix of project case studies and questionnaire served on practitioners’ performance. Whereas the toolkit was empirically tested for reliability and construct validity, the benchmark was subjected to refinement with the use of project case study.
810

The Tap Shek Kok Power Plant, Hong Kong: a marine environmental impact assessment

Lam, Wai-wai, Vivian., 林慧慧. January 1987 (has links)
published_or_final_version / Zoology / Doctoral / Doctor of Philosophy

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