• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 342
  • 340
  • 64
  • 46
  • 19
  • 15
  • 5
  • 4
  • 3
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 959
  • 959
  • 324
  • 296
  • 203
  • 137
  • 127
  • 124
  • 102
  • 83
  • 77
  • 70
  • 68
  • 66
  • 65
  • 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.
91

Spatial Analysis of the Effect of Absenteeism on Education Quality in Maynas, Peru

Engler, Nathan J. January 2007 (has links)
This thesis examines the effect of absenteeism on education quality for primary-aged public school students in the Department of Loreto, Province of Maynas, situated in the Amazonian region of north-eastern Peru. The thesis also examines the underlying reasons for absenteeism, with a focus on the contribution of childhood morbidity and socio-economic and environmental context to absenteeism, using both gender- and grade-based analyses of student level absenteeism data collected from a sample of schools in the study area. A five-component model with multiple individual indicators measuring each component of education systems defines the concept of education quality as it relates to the analysis in the thesis. The model has been demonstrated in previous research to be effective in explaining variations in education quality in Peru and elsewhere. However, the model has not been applied to this important yet under-researched area of education assessment, namely student absenteeism (at the student and school level) and its effect on education quality. In addition, spatial variations in absenteeism, based on the geographic distribution of the schools over the study area, are evaluated. This analysis allows spatial regularities or spatial randomness to be established for both absenteeism and education quality in the study area. Identifying spatial clustering of public primary schools where a high rate of student absenteeism contributes significantly to explaining overall low levels of education quality can provide education policy planners and decision-makers with insights into causal processes that need to be addressed through planned interventions in the education system.
92

Spatial Analysis of the Effect of Absenteeism on Education Quality in Maynas, Peru

Engler, Nathan J. January 2007 (has links)
This thesis examines the effect of absenteeism on education quality for primary-aged public school students in the Department of Loreto, Province of Maynas, situated in the Amazonian region of north-eastern Peru. The thesis also examines the underlying reasons for absenteeism, with a focus on the contribution of childhood morbidity and socio-economic and environmental context to absenteeism, using both gender- and grade-based analyses of student level absenteeism data collected from a sample of schools in the study area. A five-component model with multiple individual indicators measuring each component of education systems defines the concept of education quality as it relates to the analysis in the thesis. The model has been demonstrated in previous research to be effective in explaining variations in education quality in Peru and elsewhere. However, the model has not been applied to this important yet under-researched area of education assessment, namely student absenteeism (at the student and school level) and its effect on education quality. In addition, spatial variations in absenteeism, based on the geographic distribution of the schools over the study area, are evaluated. This analysis allows spatial regularities or spatial randomness to be established for both absenteeism and education quality in the study area. Identifying spatial clustering of public primary schools where a high rate of student absenteeism contributes significantly to explaining overall low levels of education quality can provide education policy planners and decision-makers with insights into causal processes that need to be addressed through planned interventions in the education system.
93

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.
94

Study of the Impact and Planning Strategies for Local Green Resource Distribution after City-County Consolidation:Case Study on Border Districts Between Kaohsiung City and County

Chien, Che-Wen 08 September 2011 (has links)
The delineation of administrative boundaries not only determines the spatial distribution of urban and rural areas but also affect the natural resources related to conservation, utilization, and management. In Taiwan, various institutional factors such as the urban development gap, the scale of administrative areas, and the administrative system level often result in uneven distribution of resources of social injustice. In this study, the starting point for the discussion on the annexation of the city and county of Kaohsiung is a comparison of similar properties in the area of space but with differences due to administrative boundaries in the distribution of local green resources, in addition to an exploration of the expansion of urban areas when there is regional integration within the resource advantages for fine-scale observations under the impact of the community. The study area will include Kaohsiung City's Lingya in the Cianjhen District and Fengshan City in Kaohsiung County. In addition, the counties and cities are the respective executive authorities within the study area; this point highlights the unique place and historical development of the human context. The research methods of this study will focus on the distribution of spatial location and different specific administrative units with respect to the local green resources analysis and evaluation. In the quantitative analysis, which will, through the landscape ecology indicators among computing tools (Fragstats 3.3R), quantify the characteristics of the landscape within the urban scale, and a geographic information system (ArcGIS 9.3R) spatial analysis module will be applied to evaluate the accessibility of the green space resources. Then a qualitative survey will be carried out using an on-site observation method and a local interview method to reach an understanding of local community resources with respect to the interactive effects and differences. The results show the existence of administrative boundaries for local green resource allocation and planning, which will produce different degrees of impact, so when the city changes in administrative areas, local green resources management institutions may also be involved in the adjustment of planning and assessment opportunities. Finally, we hope to do for the community through the development of local sustainable practices and to determine the appropriate direction for local green resource strategic planning.
95

Ecosystem health at the texas coastal bend: a spatial analysis of exposure and response

Bissett, Wesley Thurlow, Jr. 15 May 2009 (has links)
This dissertation investigated locational risks to ecosystem health associated with proximity to industrial complexes. The study was performed at the behest of ranchers and citizens living and working down-prevailing wind from the Formosa Plastics, Inc. and ALCOA facilities located in Calhoun County, Texas. Concerns expressed were for potential genotoxicity resulting from exposure to complex chemical mixtures released by the facilities. Exposure assessment of the marine environment was performed with sediments and oysters from Lavaca Bay being analyzed. Numerous chemicals were found to be present at concentrations considered likely to result in adverse responses in exposed populations. Bayesian geostatistical analysis was performed to determine if the concentrations were affected by a spatial process. Mercury and polycyclic aromatic hydrocarbons were the most notable of the chemicals found to be present at elevated concentrations and affected by a spatial process. Evaluation of maps generated from spatial modeling revealed that proximity to ALCOA resulted in elevated risks for exposure to harmful concentrations of pollutants. Genotoxicity was measured in two sentinel species. Oysters (Crassostrea virginica) were utilized for evaluation of the marine environment and cattle (Bos taurus and Bos taurus crossbred cattle) were chosen for evaluation of the terrestrial environment. Chromosomal aberration analysis was performed on oyster hematocytes. Analysis of the results failed to demonstrate the presence of an important generalized spatial process but some specific locations close to the ALCOA plant had elevations in this measure of genotoxicity. Stress as measured by the lysosomal destabilization assay was also performed on oyster hematocytes. These results were found to be affected by a significant spatial process with the highest degree of destabilization occurring in close proximity to ALCOA. Genotoxicity in cattle was evaluated with the single cell gel electrophoresis assay and chromosomal aberration analysis. Bayesian geostatistical analyis revealed the presence of important spatial processes. DNA-protein cross-linkage was the most notable with a strong indication of increased damage down-prevailing wind from the industrial complexes. Results indicated that proximity to industrial facilities increased the risk for harmful exposures, genotoxicity, and lysosomal destabilization.
96

Rock art boundaries: considering geographically limited elements within the Pecos River Style

Harrison, James Burr 30 September 2004 (has links)
This thesis examines six prominent Pecos River Style rock art anthropomorph attributes to determine if they are found in limited geographic districts of the Lower Pecos Region. Both Boyd (2003) and Turpin (2004) have suggested that spatially-segregated motif distributions exist in the rock art and that these patterns are important in understanding regional prehistoric hunter-gatherer lifeways during the Archaic Period. This study verifies that the feather hip cluster motif is geographically limited, identified only in the neighboring Seminole and Painted Canyon systems. As part of this spatial analysis, the previously undocumented principle of intersite stylistic traditions is introduced. Possible explanations for these anthropomorph attributes are also discussed. Finally, structural analyses of the six attributes are presented.
97

Analysis of site structure and post-depositional disturbance at two Early Holocene components, Richard Beene site (41BX831), Bexar County, Texas

Mason, James Bryan 30 September 2004 (has links)
Two deeply buried, well-stratified, and well-dated components dating to the Early Holocene period were excavated at the Richard Beene site (41BX831) in Bexar County, Texas. This thesis utilizes both qualitative (interpretation of maps) and quantitative (unconstrained clustering) spatial analysis techniques to identify site structure and assess post-depositional disturbance by analyzing patterns among artifact categories, selected artifacts, and features from these components. Results of spatial analysis are compared to expectations of the archaeological record based on previous research. Each component revealed a distinct pattern. The Lower Medina component (ca. 6900 B.P.) is well preserved and spatial analysis showed clear distinctions between domestic and peripheral zones. The Upper Perez component (8800 B.P.) is a fluvial lag deposit of displaced artifacts and fire-cracked rock features. Results of spatial analysis confirmed that most, if not all, of this component is disturbed, revealing no site structure.
98

Ecosystem health at the Texas coastal bend: a spatial analysis of exposure and response

Bissett, Wesley Thurlow, Jr. 10 October 2008 (has links)
This dissertation investigated locational risks to ecosystem health associated with proximity to industrial complexes. The study was performed at the behest of ranchers and citizens living and working down-prevailing wind from the Formosa Plastics, Inc. and ALCOA facilities located in Calhoun County, Texas. Concerns expressed were for potential genotoxicity resulting from exposure to complex chemical mixtures released by the facilities. Exposure assessment of the marine environment was performed with sediments and oysters from Lavaca Bay being analyzed. Numerous chemicals were found to be present at concentrations considered likely to result in adverse responses in exposed populations. Bayesian geostatistical analysis was performed to determine if the concentrations were affected by a spatial process. Mercury and polycyclic aromatic hydrocarbons were the most notable of the chemicals found to be present at elevated concentrations and affected by a spatial process. Evaluation of maps generated from spatial modeling revealed that proximity to ALCOA resulted in elevated risks for exposure to harmful concentrations of pollutants. Genotoxicity was measured in two sentinel species. Oysters (Crassostrea virginica) were utilized for evaluation of the marine environment and cattle (Bos taurus and Bos taurus crossbred cattle) were chosen for evaluation of the terrestrial environment. Chromosomal aberration analysis was performed on oyster hematocytes. Analysis of the results failed to demonstrate the presence of an important generalized spatial process but some specific locations close to the ALCOA plant had elevations in this measure of genotoxicity. Stress as measured by the lysosomal destabilization assay was also performed on oyster hematocytes. These results were found to be affected by a significant spatial process with the highest degree of destabilization occurring in close proximity to ALCOA. Genotoxicity in cattle was evaluated with the single cell gel electrophoresis assay and chromosomal aberration analysis. Bayesian geostatistical analyis revealed the presence of important spatial processes. DNA-protein cross-linkage was the most notable with a strong indication of increased damage down-prevailing wind from the industrial complexes. Results indicated that proximity to industrial facilities increased the risk for harmful exposures, genotoxicity, and lysosomal destabilization.
99

Three dimensional statistical graphs, visual cues and clustering

Vohra, Neeru Rani. January 2000 (has links)
Thesis (M.A.)--York University, 2000. Graduate Programme in Statistics. / Typescript. Includes bibliographical references (leaves 29-32). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ56213.
100

Strategies for handling spatial uncertainty due to discretization /

Windholz, Thomas K., January 2001 (has links)
Thesis (Ph. D.) in Spatial Information Science and Engineering--University of Maine, 2001. / Includes vita. Includes bibliographical references (leaves 118-132).

Page generated in 0.1101 seconds