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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.
141

MAPPING LAND COVER LAND USE CHANGE IN MBEERE DISTRICT, KENYA

Maluki, Peter Masavi 14 August 2007 (has links)
No description available.
142

A Model of Change Process and Its Use in Self-Assessment

Ford, Matthew W. January 2000 (has links)
No description available.
143

Political culture, governance and climate change adaptation : case study of South Korea

Park, Keumjoo January 2013 (has links)
Many scholars highlight the essence of a participatory governance approach to climate change adaptation and the positive impact of allowing multiple actors participation in the process of decision making as a determinant for successful adaptation to climate change. However, political culture in some societies does not support participation, and people are neither interested nor even aware of political actions. There are very few studies carried out that examine cultural, especially political cultural, influences over governing climate change adaptation. In response to this academic gap, this research aims to investigate how political culture influences a governance approach to climate change adaptation. Using an empirical case study of the process of formulating national climate change adaptation policies in South Korea, this study examines the way decisions are made about climate change policies under ‘dominant bureaucratic’, ‘authoritarian’ and ‘weak participant’ political cultures and investigates how such political cultures will hamper or encourage a governance approach to effective climate change adaptation. This study therefore advances knowledge about how political culture influences climate change adaptation. It provides a basis for comparative analyses of other political cultures in different regions and will enable scholars to understand the challenges that particular forms of governance hold for promoting climate change adaptation.
144

The relationship between organizational structural variables and the utilization of nursing practice innovations

Derenowski, Eileen January 1988 (has links)
This research sampled a group of 261 nurse managers to test the relationships among organizational structural variables and the utilization of nursing practice innovations. Subjects completed instruments that measured organizational complexity, centralization, formalization and the utilization of nursing practice innovations. Pearson correlations revealed a significant positive relationship between utilization of nursing practice innovations and individual perception of autonomy in decision-making. Within organizational centralization the decision-making components of organizational centralization entered into a multiple regression equation which explained 27% of the variance in utilization of nursing practice innovations, with total decision-making contributing the greatest amount of variance. Organizational complexity variables entered into a multiple regression equation which explained 2% of the variance in utilization of nursing practice innovations with the certification variable explaining the majority of the variance. Five variables related to organizational centralization and complexity together explained 28% of the variance in utilization of nursing practice innovations with the total decision-making variable explaining the majority of the variance.
145

Dynamically Downscaled NARCCAP Climate Model Simulations| An Evaluation Analysis over Louisiana

Tamanna, Marzia 30 December 2015 (has links)
<p> In order to make informed decisions in response to future climate change, researchers, policy-makers, and the public need climate projections at the scale of few kilometers, rather than the scales provided by Global Climate Models. The North American Regional Climate Change Assessment Program (NARCCAP) is such a recent effort that addresses this necessity. As the climate models contain various levels of uncertainty, it is essential to evaluate the performance of such models and their representativeness of regional climate characteristics. When assessing climate change impacts, precipitation is a crucial variable, due to its direct influence on many aspects of our natural-human ecosystems such as freshwater resources, agriculture and energy production, and health and infrastructure. The current study performs an evaluation analysis of precipitation simulations produced by a set of dynamically downscaled climate models provided by the NARCCAP program. The Assessment analysis is implemented for a period that covers 20 to 30 years (1970-1999), depending on joint availability of both the observational and the NARCCAP datasets. In addition to direct comparison versus observations, the hindcast NARCCAP simulations are used within a hydrologic modeling analysis for a regional ecosystem in coastal Louisiana (Chenier Plain). The study concludes the NARCCAP simulations have systematic biases in representing average precipitation amounts, but are successful at capturing some of the characteristics on spatial and temporal variability. The study also reveals the effect of precipitation on salinity concentrations in the Chenier Plain as a result of using different precipitation forcing fields. In the future, special efforts should be made to reduce biases in the NARCCAP simulations, which can then lead to a better presentation of regional climate scenarios for use by decision makers and resource managers.</p>
146

The actual rhetoric of change in the UK clearing banks

Hughes, Mark January 1998 (has links)
Whilst, the reality of changing organizations is accepted, understanding about the rhetoric of change in organizations is still evolving. This thesis provides new insights into the rhetoric of change in organizations through addressing the following research aims. i. To establish a theoretical framework for classifying change. ii. To identify and analyse the actual rhetoric of change of senior management in the UK clearing banks. iii.To compare the actual rhetoric of change identified in the UK clearing banks against the theoretical framework for classifying change. iv. To develop an Actual Rhetoric of Change Framework. The Annual Reports and Internal Newspapers of Barclays, Lloyds, Midland and National Westminster Bank over the five years 1990 to 1994 were analysed using discourse analysis. This naturally occurring data contained the actual rhetoric of change. In terms of banking change, this thesis makes an original contribution to knowledge by identifying and analysing the actual rhetoric of change in banking. The thesis makes original contributions to knowledge about the rhetoric of changing organizations in two ways. Firstly the development of the literature based Change Classifications Framework. Secondly, through comparing the literature and the data, an Actual Rhetoric of Change Framework was developed. The Actual Rhetoric of Change Framework predicts that change will be depicted in organizations as being challenging, constant, coherent, contextualised and chronological.
147

Environmental change and flooding in the Gambia River Basin

Amara, Sakpa S. January 1993 (has links)
It is argued in this thesis that the climate signal shows more strongly in the runoff regime of the Gambia River Basin (GRB) than the signal from deforestation. Partial and multiple regression was used to partition the effects on runoff of rainfall characteristics and deforestation over the GRB since the turn of this century. The expected shorter, higher more rapidly responding wet season flood peaks which result from deforestation have not occurred in the GRB. Rather, peak floods have fluctuated since the beginning of the century, but showing a clear declining trend similar to the rainfall regime. The large size (z 7550 km') of the sub-catchments of the GRB inhibit synchronisation of the rapid runoff that is associated with deforestation. Furthermore, deforestation, as it occurs in the GRB, takes place piece-meal as small plots of land are cleared. The nature of clearance of vegetation is important; the vegetation cleared is either replaced with another type of vegetation, for example, groundnuts or millet, or is soon allowed to recover after a cropping phase. Surface and sub-surface hydrological processes within the GRB are therefore not subjected to the severe form of alteration that characterise massive and total clearance of vegetation schemes in urban development. However, deforestation has significantly affected low flowsthere are now longer periods of lower dry season flows, and these are ascribed to the diminishing recharge of ground water. By augmenting overland flow and reducing interception and infiltration, deforestation causes a reduction in ground water recharge, which is an important component of dry season flows. Both climate change and deforestation have worked in parallel to cause a fluctuating but declining flow regime of the Gambia River. This, in turn, affects both the agricultural potential and productivity of the GRB.
148

Studies on polymorphic proteins of Plasmodium falciparum

Fenton, Brian Forbes Neil January 1987 (has links)
No description available.
149

Altering the thermal regime of soils below heated buildings in the continuous and discontinuous permafrost zones of Alaska

Perreault, Paul Vincent 27 May 2016 (has links)
<p> This research investigates the impacts of thermal insulation on the thermal regime of soils below heated buildings in seasonally and perennially frozen soils. The research provides practical answers (A) for designing frost-protected shallow foundations in unfrozen soils of the discontinuous permafrost zone in Alaska and (B) shows that applying seasonal thermal insulation can reduce the risk of permafrost thawing under buildings with open crawl spaces, even in warming climatic conditions. </p><p> At seasonal frost sites, this research extends frost-protected shallow foundation applications by providing design suggestions that account for colder Interior Alaska&rsquo;s air freezing indices down to 4,400 &deg;C&dot;d (8,000 &deg;F&dot;d). This research includes field studies at six Fairbanks sites, mathematical analyses, and finite element modeling. An appendix includes frost-protected shallow foundation design recommendations. Pivotal findings include the discovery of more pronounced impacts from horizontal frost heaving forces than are likely in warmer climates. </p><p> At permafrost sites, this research investigates the application of manufactured thermal insulation to buildings with open crawl spaces as a method to preserve soils in the frozen state. This research reports the findings from using insulation to reduce permafrost temperature, and increase the bearing capacity of permafrost soils. Findings include the differing thermal results of applying insulation on the ground surface in an open crawl space either permanently (i.e., left in place), or seasonally (i.e., applied in warm months and removed in cold months). Research includes fieldwork in Fairbanks, and finite element analyses for Fairbanks, Kotzebue, and Barrow. Pivotal findings show that seasonal thermal insulation effectively cools the permafrost. By contrast, Fairbanks, Kotzebue, and Barrow investigations show that permanently applied thermal insulation decreases the active layer, while also increasing (not decreasing) the permafrost temperature. </p><p> Using seasonal thermal insulation, in a controlled manner, satisfactorily alters the thermal regime of soils below heated buildings and provides additional foundation alternatives for arctic buildings.</p>
150

Climate Change and Forest Biodiversity in the Eastern United States: Insights from Inventory Data

Zhu, Kai January 2014 (has links)
<p>Ecologists have long been interested in the relationships between climate change and forest biodiversity. For centuries, the scientific problems remain understanding the patterns of climate variation, forest geographic distribution, and demographic dynamics. Besides scientific merits, these questions will also help forest managers and policy makers to anticipate how forests respond to global change. This dissertation tackles these problems by using statistical modeling on climate and forest inventory data in the eastern United States.</p><p>In Chapter 1, we ask the question on the observed tree range distributions in response to contemporary climate change in the eastern United States. Tree species are expected to track warming climate by shifting their ranges to higher latitudes or elevations, but current evidence of latitudinal range shifts for suites of species is largely indirect. In response to global warming, offspring of trees are predicted to have ranges extend beyond adults at leading edges and the opposite relationship at trailing edges. Large-scale forest inventory data provides an opportunity to compare present latitudes of seedlings and adult trees at their range limits. Using the USDA Forest Service's Forest Inventory and Analysis data, we directly compared seedling and tree 5th and 95th percentile latitudes for 92 species in 30 longitudinal bands for 43,334 plots across the eastern United States. We further compared these latitudes with 20th century temperature and precipitation change and functional traits, including seed size and seed spread rate. Results suggest that 58.7% of the tree species examined show the pattern expected for a population undergoing range contraction, rather than expansion, at both northern and southern boundaries. Fewer species show a pattern consistent with a northward shift (20.7%) and fewer still with a southward shift (16.3%). Only 4.3% are consistent with expansion at both range limits. When compared with the 20th century climate changes that have occurred at the range boundaries themselves, there is no consistent evidence that population spread is greatest in areas where climate has changed most; nor are patterns related to seed size or dispersal characteristics. The fact that the majority of seedling extreme latitudes are less than those for adult trees may emphasize the lack of evidence for climate-mediated migration, and should increase concerns for the risks posed by climate change.</p><p>In Chapter 2, we ask the question on tree abundance within geographic range responding to climate variation in the eastern United States. Tree species are predicted to track future climate by shifting their geographic distributions, but climate-mediated migrations are not apparent in a recent continental-scale analysis (Chapter 1). To better understand the mechanisms of a possible migration lag, we analyzed relative recruitment patterns by comparing juvenile and adult tree abundances in climate space. One would expect relative recruitment to be higher in cold and dry climates as a result of tree migration with juveniles located further poleward than adults. Alternatively, relative recruitment could be higher in warm and wet climates as a result of higher tree population turnover with increased temperature and precipitation. Using the USDA Forest Service's Forest Inventory and Analysis data at regional scales, we jointly modeled juvenile and adult abundance distributions for 65 tree species in climate space of the eastern United States. We directly compared the optimal climate conditions for juveniles and adults, identified the climates where each species has high relative recruitment, and synthesized relative recruitment patterns across species. Results suggest that for 77% and 83% of the tree species, juveniles have higher optimal temperature and optimal precipitation, respectively, than adults. Across species, the relative recruitment pattern is dominated by relatively more abundant juveniles than adults in warm and wet climates. These different abundance-climate responses through life history are consistent with faster population turnover and inconsistent with the geographic trend of large-scale tree migration. Taken together, this juvenile-adult analysis suggests that tree species might respond to climate change by having faster turnover as dynamics accelerate with longer growing seasons and higher temperatures, before there is evidence of poleward migration at biogeographic scales.</p><p>In Chapter 3, we ask the question on the demographic dynamics of density dependence at the individual tree level in eastern US forests. Density dependence could maintain diversity in forests, but studies disagree on its importance. Part of the disagreement results from the fact that different studies evaluate different responses (per-seedling or per-adult survival or growth) of different stages (seeds, seedlings, or adults) to different inputs (density of seedlings, density or distance to adults). Most studies are conducted on a single site and thus are difficult to generalize. Using USDA Forest Service's Forest Inventory and Analysis data, we analyzed over a million seedling-to-sapling recruitment observations of 50 species for both per-tree (adult) and per-seedling recruitment rates, controlling for climate effects in eastern US forests. We focused on per-tree recruitment as it is most likely to promote diversity at the population level, and it is most likely to be identified in observational or experimental data. To understand the prevalence of density dependence, we quantified the proportion of species with significant positive or negative effects. To understand the strength of density dependence, we determined the magnitude of effects among conspecifics and heterospecifics, and how it changes with overall species abundance. We found that the majority of the 50 species have significant density dependence effects, mostly negative, on both per-tree and per-seedling recruitment. Per-tree recruitment is positively associated with conspecific seedlings, saplings, and heterospecific saplings, negatively associated with heterospecific seedlings, conspecific and heterospecific trees. Per-seedling recruitment is positively associated with conspecific and heterospecific saplings, but negatively associated with conspecific and heterospecific seedlings and trees. Furthermore, for both per-tree and per-seedling recruitment, density dependence effects are stronger for conspecific than heterospecific neighbors. However, the strength of these effects does not vary with species abundance. We conclude that density dependence is pervasive, especially for per-tree recruitment, and its strength among conspecifics and heterospecifics is consistent with the predictions of the Janzen-Connell hypothesis.</p> / Dissertation

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