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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.
111

Spatial analysis of thermal aging of overhead power transmission lines

Bhuiyan, Md. Mafijul Islam Unknown Date
No description available.
112

Spatial analysis and efficiency of systematic designs in intercropping experiments.

Wandiembe, Symon Peter. January 2002 (has links)
In studies involving intercropping plant populations, the main interest is to locate the position of the maximum response or to study the response pattern. Such studies normally require many plant population levels. Thus, designs such as spacing systematic designs that minimise experimental land area are desired. Randomised block designs may not perform well as they allow few population levels which may not span the maximum or enable exploration of other features of the response surface. However, lack of complete randomisation in systematic designs may imply spatial variability (largescale and small-scale variations i.e. trend and spatial dependence) in observations. There is no correct statistical method laid out for data analysis from such designs. Given that spacing systematic designs are not well explored in literature, the main thrusts of this study are two fold; namely, to explore the use of spatial modelling techniques in analysing and modelling data from systematic designs, and to evaluate the efficiency of systematic designs used in intercropping experiments. Three classes of models for trend and error modelling are explored/introduced. These include spatial linear mixed models, semi-parametric mixed models and beta-hat models incorporating spatial variability. The reliability and precision of these methods are demonstrated. Relative efficiency of systematic designs to completely randomised design are evaluated. The analysis of data from systematic designs is shown be easily implemented. Measures of efficiency that include <pp directed measures (A and E criteria), D1 and DB efficiencies for regression parameters, and power are used. Systematic designs are shown to be efficient; on average 72% for A and E- efficiencies and 93% for D1 and DB efficiencies. Overall, these results suggest that systematic designs are suitable and reliable for intercropping plant population studies. / Thesis (M.Sc.) - University of Natal, Pietermaritzburg, 2002
113

Liquefaction evaluation using a spatial analysis system

Luna, Ronaldo 05 1900 (has links)
No description available.
114

Rebuilding for Sustainability: Spatial Analysis of Bolivar Peninsula after Hurricane Ike

Subasinghe Arachchilage Don, Chamila Tharanga 2011 December 1900 (has links)
Recurring extreme events of nature challenge disaster-prone settlements in complex ways. Devastating property damages are one of the tests of survival for such settlements in both economic and social terms. It also provides unique opportunities to rethink the environment cleared by massive natural disasters. However, rebuilding for long-term resiliency is one of the least investigated areas, particularly when employing tacit knowledge in the sustainable recovery process. This study examines the post-disaster rebuilding process in spatial terms for Bolivar Peninsula in the aftermath of Hurricane Ike. It further investigates the nexus between connectivity among open space networks to various levels of surge damage among Bolivar spontaneous settlements. The study uses syntactical methods to measure axial connectivity of the Bolivar Peninsula access grid and one-way Analysis of Variance to interpret the way connectivity varies along the no damage to destroyed damage scale. In addition, the permeability rubric analyzes the elevation characteristics of houses that demonstrated higher probabilities of survival through a logistic regression. The conclusions are based on two basic premises. Local knowledge demands an indefinite time to be adapted and mobilized because of the increasing intensity of natural disasters. In addition, the high frequency of disaster events significantly challenges the versatility of local coping and survival strategies. The results reveal that the connectivity of the access grid has an inversely proportional relationship with various damage levels, particularly for no damage and destroyed. Furthermore, out of a number of resiliency characteristics listed in the literature, only ground elevation and ground enclosure demonstrated probability significances for survival. Potentially, the results of this research could support three significant outcomes pertaining to sustainable disaster recovery: preserving place character, social justice among affected groups, and promoting rapid recovery.
115

The Effects of Urbanization on Baseflow over Time: An Analysis of Changing Watersheds and Stream Flow Response in Georgia

Furtsch, Emily B 09 May 2015 (has links)
This study examines the relationship between baseflow and urbanization over time with the help of spatial analysis using Geographic Information Systems. The urbanization parameters used were population and urban land use. Five urban and three non-urban streams were chosen for analysis in the state of Georgia. Four percentile baseflows for each stream were identified and analyzed for trends over time. A correlation analysis was also run to determine how baseflow varies as a function of urbanization. According to the trend analysis, the baseflows over time were considered stable or had no statistically significant trend. The correlation analysis between baseflow and urbanization revealed some scattered relationships though a general conclusion cannot be drawn. The simplicity of the study may have contributed to not capturing all of the baseflow changes with the urbanization parameters.
116

AN ECONOMETRIC ANALYSIS OF INFANT MORTALITY, POLLUTION, AND INCOME IN THE U.S. COUNTIES

Somov, Margarita Yuri 01 January 2004 (has links)
The concept of economic development has broadened to include environmental quality and population health. Interactions between income and pollution, income and health, and pollution and health have been studied separately by researchers from various disciplines. This study attempts to unify several different research strands and analyze simultaneous interactions between population health, measured by the infant mortality rate, pollution, and income in one endogenous system. Socioeconomic, racial, and rural urban disparities in infant mortality, pollution, and income are analyzed. The simultaneous equation system, estimated using the two-stage least squares method, tests whether pollution effects on infant mortality are outweighed by income effects. The study finds that income is a stronger determinant of infant mortality than pollution. Evidence for the environmental Kuznets curve is ambiguous. Disparities in infant mortality, pollution, and income are correlated with counties rural-urban status, income inequality, and ethnic diversity. Regional patterns identify wide geographical differences in levels of pollution, income, and infant mortality. The Southeast region stands out as a region with the highest infant mortality rate, relatively high levels of air pollution and chemical releases, and low per capita incomes.
117

Eliciting and mapping the attributes of landscape perception : an integration of personal construct theory (PCT) with geographic information systems (GIS)

Harvey, Rachel January 1995 (has links)
Scotland's tourist industry partly depends upon the quality of the Scottish landscape. However, despite demands for improved management of landscape resources, there is no standard method for the assessing landscape quality. This research takes a user-based approach to this problem and explores the use of Kelly's Personal Construct Theory (PCT) in eliciting underpinning attributes and dimensions of perception in a range of uses and across a range of Scottish landscapes. A novel aspect of the research is that it involves experimentation in mapping the resultant constructs through use of a Geographic Information System (GIS). Sixteen key constructs were gained from one to one. interviews and used in the preliminary mapping experiments. These showed that it was possible to express the constructs spatially. To evaluate between user group/landscape type responses a questionnaire was designed, piloted and applied. A total of 1286 responses were analyzed. Differences were found between landscape type but were stronger between user groups. The research has demonstrated that the application of PCT coupled to GIS is a valuable way of exploring landscape perception/landscape quality and their spatial expression.
118

Measuring spatial mobility - towards new perspectives on accessibility

Mohall, Marcus January 2015 (has links)
In recent years, spatial data derived from cell phones has become increasingly recognized as a valuable data source for urban analysis. Using a sizeable dataset depicting the physical movements of several million Swedish and Danish cell phones during 24 hours, an analysis of aggregated individual mobility levels and mobility patterns is conducted. The analysis covers two measurements of mobility, total diurnal mobility and commuting mobility. Findings indicate that phone data may provide seminal insights on otherwise scarcely accessible information on how space is experienced and interacted with depending on the individual's residential location. The data is analysed using a broad set of spatial analysis techniques incorporating both statistical and visual representations of spatial mobility and spatial relationships.
119

Spatial Patterns of Neighbourhood Crime in Canadian Cities: The Influence of Neighbourhood and City Contexts

Luo, Xue January 2012 (has links)
The main goal of this study is to investigate the spatial patterns of police-reported crime rates across select Canadian urban neighbourhoods and to explore their relationships with both neighbourhood- and city-level characteristics, as well as neighbourhood spatial dependence. Analyses were based on aggregated data from the 2001 Incident-Based Uniform Crime Reporting Survey (UCR2) and the Census of Population for six Canadian cities: Edmonton, Halifax, Montreal, Saskatoon, Thunder Bay and Toronto. Exploratory spatial data analysis (ESDA) was used to examine the spatial distribution of crime as well as to test for spatial dependence in the crime data. By using multilevel modelling and spatial regression techniques, neighbourhood violent and property crime rates were modeled respectively as a function of both city- and neighbourhood-level contextual variables while controlling for spatial dependence. The results show that crime is not distributed randomly, but tends to be concentrated in particular neighbourhoods, notably around the city centers of these cities. Neighbourhood variance in crime rates is not only dependent on local neighbourhood characteristics, but also on the characteristics of surrounding neighbourhoods, as well as the broader city environment where neighbourhoods are embedded. These findings suggest that strategies aimed at preventing or reducing crime should be developed in light of specific local neighbourhood contexts, while taking into account social forces external to the immediate neighbourhood in the wider social environment.
120

Hierarchical spatio-temporal models for environmental processes

Arab, Ali, January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed Nov. 21, 2007). Vita. Includes bibliographical references.

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