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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

Dasymetric stratification of a flood plain: development and refinement of the HAZUS flood mapping tool for Canada

Howells, Angela 16 September 2016 (has links)
The high frequency and cost of flooding in Canada has demonstrated the need for effective risk assessment (Public Safety Canada (PSC), 2010). In response to this need, the United States Federal Emergency Management Agency (FEMA) developed HAZUS, a hazard risk assessment tool which relies on a geographic information system (GIS) (FEMA, 2015). Unfortunately, in many rural communities in Canada, only aggregate population data may be available. In those cases, the ability to further partition aggregated data may prove essential in generating robust and accurate risk assessments. The results of this study show that HAZUS can be adapted for use in Canada and provides a new methodology for conducting hazard estimations in areas where available data is coarsely aggregated. There was a strong relationship between nighttime light and population density. High populations were associated with developed land cover classification. These relationships can be used to increase the accuracy of HAZUS predictions. / October 2016
2

A Dasymetric Approach to Estimating Domestic Groundwater Well Use in the United States

Murray, Andrew R. January 2016 (has links)
No description available.
3

A comparative analysis of areal interpolation methods

Hawley, Kevin J. January 2005 (has links)
No description available.
4

Estimating Health Outcomes and Determinants in Rural Ottawa: An Integration of Geographical and Statistical Techniques

Mosley, Brian 12 November 2012 (has links)
Many health geography studies, including the Ottawa Neighbourhood Study (ONS), have faced significant challenges uncovering local variation in patterns of community health in rural areas. This is due to the fact that sparsely populated rural areas make it difficult to define neighbourhoods that are representative of the social and resource utilization patterns of the individuals therein. Moreover, rural areas yield small samples from population-based regional health surveys and this leads to insufficient sample sizes for reliable estimation of health determinants and outcomes. In response to this issue this thesis combines geographical and statistical techniques which allow for the simulation of health variables within small areas and populations within rural Ottawa. This methodological approach combines the techniques of dasymetric mapping and statistical micro-simulation in an innovative way, which will allow health geography researchers to explore health determinants and health outcomes at small spatial scales in rural areas. Dasymetric mapping is used to generate a statistical population surface over Ottawa and then estimate socio-economic (SES) variables within small neighbourhood units within rural Ottawa. The estimated SES variables are then used as correlate variables to simulate health determinant and health outcome variables form the Canadian Community Health Survey (CCHS) using statistical micro-simulation. Through this methodology, simulations of specific health determinants and outcome can be investigated at small spatial scales within rural areas. Dasymetric mapping provided neighbourhood-level population estimates that were used to re-weight as set of SES variables that were correlates with those in the Canadian Community Health Survey (CCHS). These neighbourhood-level correlates allowed microsimulation and consequent spatial exploration of prevalence for smoking, binge drinking, obesity, self-rated mental health, and the presence of two or more chronic conditions. The methodology outlined in this paper, provides and innovative way of exploring health determinants and health outcomes in neighbourhoods for which population and health statistics are not traditionally collected at levels that would allow traditional statistical analyses of prevalence.
5

Formas de representação da densidade demográfica para a Região Metropolitana de São Paulo com base em dados do Censo 2010 do IBGE / Means of representation of demographic density for Região Metropolitana de São Paulo based in 2010 IBGE Census data

Yamada, Mauricio 19 February 2016 (has links)
Esta pesquisa tem como objetivo principal desenvolver formas de representação da densidade demográfica para a Região Metropolitana de São Paulo (RMSP). Acredita-se que estes estudos possam estabelecer metodologias de trabalho úteis para subsidiar ações de planejamento e gestão desta complexa metrópole. Os estudos desenvolvem um procedimento com análise espacial realizado em ambiente SIG, o tratamento dasimétrico. O tratamento dasimétrico procura resolver certas incoerências do método coroplético, quando este é aplicado a bases censitárias, para isso conta com bases auxiliares de informação para melhor localizar a distribuição de densidade populacional. Tal procedimento é oportuno pois conta-se com considerável patrimônio cartográfico disponível para a área em estudo. Para dar coerência aos procedimentos realizados, faz uma revisão com um viés humanista, procurando entender o estado da evolução da Cartografia, posicionando a análise espacial em meio a outras linguagens, correntes cartográficas e suas discussões. / This research has as main purpose to develop types of demographic density representation from the Região Metropolitana de São Paulo (RMSP). Its believed that studies could establish useful work methodologies to subsidize planning actions and management of this complex metropolis. Studies develop a procedure with spatial analysis accomplished in GIS environment, the dasymetric treatment. The dasymetric treatment seeks to solve certain inconsistencies from choropleth method, when this is applied to a census basis, for this auxiliary basis of information is needed to better locate the distribution of population density. Such procedure is timely because it can count on considerable cartographic property available to the study site. To give consistency for performed procedures, revises with a humanistic bias, looking for understand the evolution status of Cartography, positioning the spatial analysis amid other languages, cartographic chains and their discussions.
6

Assessing the Environmental Justice Implications of Flood Hazards in Miami, Florida

Montgomery, Marilyn Christina 09 July 2014 (has links)
While environmental justice (EJ) research in the U.S. has traditionally focused on inequities in the distribution of technological hazards, the disproportionate impacts of Hurricane Katrina on racial minorities and socioeconomically disadvantaged households have prompted researchers to investigate the EJ implications of natural hazards such as flooding. Recent EJ research has also emphasized the need to examine social inequities in access to environmental amenities. Unlike technological hazards such as air pollution and toxic waste sites, areas exposed to natural hazards such as hurricanes and floods have indivisible amenities associated with them. Coastal property owners are exposed to flood hazards, but also enjoy water views and unhampered access to oceans and the unique recreational opportunities that beaches offer. Conversely, dense urban development and associated impervious surfaces increase likelihood of floods in inland areas which may lack the amenities of proximity to open water. This dissertation contributes to the emerging literature on EJ and social vulnerability to natural hazards by analyzing racial, ethnic, and socioeconomic inequities in the distribution of flood risk exposure in the Miami Metropolitan Statistical Area (MSA), Florida--one of the most hurricane-prone areas in the world and one of the most ethnically diverse MSAs in the U.S. The case study evaluates the EJ implications of residential exposure to coastal flood risk, inland flood risk, and no flood risk, in conjunction with coastal water related amenities, using geographic information science (GIS)-based techniques and logistic regression modeling to estimate flood risk exposure. Geospatial data from the Federal Emergency Management Agency (FEMA) are utilized to delineate coastal and inland 100-year flood hazard zones. Socio-demographic variables previously utilized in EJ research are obtained from tract level data published in the 2010 census and 2007-2011 American Community Survey five-year estimates. Principal components analysis is employed to condense several socio-demographic attributes into two neighborhood deprivation indices that represent economic insecurity and instability, respectively. Indivisible coastal water related amenities are represented by control variables of percent seasonal homes and proximity to public beach access sites. Results indicate that racial/ethnic minorities and those with greater social vulnerability based on the neighborhood deprivation indices are more likely to reside in inland flood zones and areas outside 100-year flood zones, while residents in coastal flood zones are disproportionately non-Hispanic White. Moreover, residents exposed to coastal flood risk tend to live in areas with ample coastal water related amenities, while racial/ethnic minorities and individuals with higher neighborhood deprivation who are exposed to inland flood risk or no flood risk reside in areas without coastal water related amenities. This dissertation elucidates the importance of EJ research on privilege and access to environmental amenities in conjunction with environmental hazards because areas exposed to natural hazards are likely to offer indivisible benefits. Estimating people and places exposed to hazards for EJ research becomes difficult when the boundaries of census areal units containing socio-demographic data do not match the boundaries of hazard exposure areas. This challenge is addressed with an application of dasymetric spatial interpolation using GIS-based techniques to disaggregate census tracts to inhabited parcels. Several spatial interpolation methods are assessed for relative accuracy in estimating population densities for the Miami MSA, and the output units from the most accurate method are employed in EJ regression analyses. The dasymetric mapping efforts utilized herein contribute to research on the modifiable areal unit problem (MAUP) and its effects on statistical analyses. Since the dasymetric mapping technique used for EJ analyses disaggregates census tracts to the inhabited parcel level, the results of the associated analyses for flood hazards exposure and access to coastal water related amenities should be more reliable than those based on tracts. The enhanced accuracy associated with inhabited parcels is a result of using a more precise geospatial depiction of residential populations, which leads to a more accurate portrayal of disproportionate exposure to flood hazards. Consequently, this dissertation contributes methodologically to GIS-based techniques of dasymetric spatial interpolation and empirically to EJ analysis of flood hazards with indivisible coastal water related amenities.
7

Estimating Health Outcomes and Determinants in Rural Ottawa: An Integration of Geographical and Statistical Techniques

Mosley, Brian 12 November 2012 (has links)
Many health geography studies, including the Ottawa Neighbourhood Study (ONS), have faced significant challenges uncovering local variation in patterns of community health in rural areas. This is due to the fact that sparsely populated rural areas make it difficult to define neighbourhoods that are representative of the social and resource utilization patterns of the individuals therein. Moreover, rural areas yield small samples from population-based regional health surveys and this leads to insufficient sample sizes for reliable estimation of health determinants and outcomes. In response to this issue this thesis combines geographical and statistical techniques which allow for the simulation of health variables within small areas and populations within rural Ottawa. This methodological approach combines the techniques of dasymetric mapping and statistical micro-simulation in an innovative way, which will allow health geography researchers to explore health determinants and health outcomes at small spatial scales in rural areas. Dasymetric mapping is used to generate a statistical population surface over Ottawa and then estimate socio-economic (SES) variables within small neighbourhood units within rural Ottawa. The estimated SES variables are then used as correlate variables to simulate health determinant and health outcome variables form the Canadian Community Health Survey (CCHS) using statistical micro-simulation. Through this methodology, simulations of specific health determinants and outcome can be investigated at small spatial scales within rural areas. Dasymetric mapping provided neighbourhood-level population estimates that were used to re-weight as set of SES variables that were correlates with those in the Canadian Community Health Survey (CCHS). These neighbourhood-level correlates allowed microsimulation and consequent spatial exploration of prevalence for smoking, binge drinking, obesity, self-rated mental health, and the presence of two or more chronic conditions. The methodology outlined in this paper, provides and innovative way of exploring health determinants and health outcomes in neighbourhoods for which population and health statistics are not traditionally collected at levels that would allow traditional statistical analyses of prevalence.
8

Exurban Development: Mapping, Locating Factors, and Ecological Impact Analysis using GIS and Remote Sensing

Shrestha, Namrata 31 August 2012 (has links)
Anthropogenic disturbance in a landscape can take various forms, including residential development, which has substantial impact on the world’s ecosystems. Exurban development, characterized by low density residential development outside urban areas, was and continues to be one of the fastest growing forms of residential development in North America. It has disproportionately large ecological impacts relative to its footprint, yet is mostly overlooked in scientific studies. Specifically, a lack of spatially explicit (disaggregate) data on exurban development at regional level has contributed to a very limited understanding of this interspersed low density development. The main goal of this dissertation is to provide an increased understanding of exurban development in terms of its location, locating factors, and conservation and ecological implications at regional level, especially to enable incorporation of exurban information in the decision making processes. For this I asked four specific questions in this dissertation: (i) Where exactly is exurban development? (ii) What are the most likely factors that influence exurban development location? (iii) How does current and future development conflict with conservation goals? And (iv) What is the extent of the exurban development’s ecological impacts? Using a heterogeneous landscape, the County of Peterborough (Ontario, Canada), as the case study this dissertation undertook a number of separate yet related analyses that collectively provided the improved understanding of exurban development. The investigation of traditionally used surrogates for development, like roads and census data, and a more direct remote sensing method, using moderate resolution SPOT/HRVIR imagery, provided insights and contributed to development of spatially explicit data on exurban development. The evaluation of several commonly hypothesized locating factors in relation to exurban development revealed some of the major influences on the location of this development, especially in the context of Ontario. This research contributed to our understanding of the future risks of land conversion and identification of potential conflict areas between development and conservation plans in the study area. Lastly, examining the ecological impact of exurban development including associated roads, in terms of functions such as barrier effects and landscape connectivity, highlighted the importance of these seldom included anthropogenic disturbances in land and conservation planning. The contributions of this research to the existing body of knowledge are threefold. First, this dissertation reveals the limitations associated with existing methods used to map exurban development and presents a relatively easy, effective, automated and operational method to delineate exurban built areas at regional level using GIS and remote sensing. Second, the analyses conducted in this dissertation repeatedly highlights the importance of incorporating fine level details on exurban development in land and conservation planning as well as ecological impact assessments and presents methods and tools that can systematically and scientifically integrate this information in decision making framework. Third, this study conducted one of a kind, comprehensive and spatially explicit study on exurban development in Canada, where there is near absence of such research. With the rarely available exurban built footprint data delineated for the study area, this study not only identified the potential locating factors, future conversion risk, and conflict areas between development and conservation plans, but also quantified ecological impact in terms of landscape function, namely barrier effects and landscape connectivity, using a relatively novel circuit theoretic approach that can directly inform land and conservation decision planning process.
9

Exurban Development: Mapping, Locating Factors, and Ecological Impact Analysis using GIS and Remote Sensing

Shrestha, Namrata 31 August 2012 (has links)
Anthropogenic disturbance in a landscape can take various forms, including residential development, which has substantial impact on the world’s ecosystems. Exurban development, characterized by low density residential development outside urban areas, was and continues to be one of the fastest growing forms of residential development in North America. It has disproportionately large ecological impacts relative to its footprint, yet is mostly overlooked in scientific studies. Specifically, a lack of spatially explicit (disaggregate) data on exurban development at regional level has contributed to a very limited understanding of this interspersed low density development. The main goal of this dissertation is to provide an increased understanding of exurban development in terms of its location, locating factors, and conservation and ecological implications at regional level, especially to enable incorporation of exurban information in the decision making processes. For this I asked four specific questions in this dissertation: (i) Where exactly is exurban development? (ii) What are the most likely factors that influence exurban development location? (iii) How does current and future development conflict with conservation goals? And (iv) What is the extent of the exurban development’s ecological impacts? Using a heterogeneous landscape, the County of Peterborough (Ontario, Canada), as the case study this dissertation undertook a number of separate yet related analyses that collectively provided the improved understanding of exurban development. The investigation of traditionally used surrogates for development, like roads and census data, and a more direct remote sensing method, using moderate resolution SPOT/HRVIR imagery, provided insights and contributed to development of spatially explicit data on exurban development. The evaluation of several commonly hypothesized locating factors in relation to exurban development revealed some of the major influences on the location of this development, especially in the context of Ontario. This research contributed to our understanding of the future risks of land conversion and identification of potential conflict areas between development and conservation plans in the study area. Lastly, examining the ecological impact of exurban development including associated roads, in terms of functions such as barrier effects and landscape connectivity, highlighted the importance of these seldom included anthropogenic disturbances in land and conservation planning. The contributions of this research to the existing body of knowledge are threefold. First, this dissertation reveals the limitations associated with existing methods used to map exurban development and presents a relatively easy, effective, automated and operational method to delineate exurban built areas at regional level using GIS and remote sensing. Second, the analyses conducted in this dissertation repeatedly highlights the importance of incorporating fine level details on exurban development in land and conservation planning as well as ecological impact assessments and presents methods and tools that can systematically and scientifically integrate this information in decision making framework. Third, this study conducted one of a kind, comprehensive and spatially explicit study on exurban development in Canada, where there is near absence of such research. With the rarely available exurban built footprint data delineated for the study area, this study not only identified the potential locating factors, future conversion risk, and conflict areas between development and conservation plans, but also quantified ecological impact in terms of landscape function, namely barrier effects and landscape connectivity, using a relatively novel circuit theoretic approach that can directly inform land and conservation decision planning process.
10

Formas de representação da densidade demográfica para a Região Metropolitana de São Paulo com base em dados do Censo 2010 do IBGE / Means of representation of demographic density for Região Metropolitana de São Paulo based in 2010 IBGE Census data

Mauricio Yamada 19 February 2016 (has links)
Esta pesquisa tem como objetivo principal desenvolver formas de representação da densidade demográfica para a Região Metropolitana de São Paulo (RMSP). Acredita-se que estes estudos possam estabelecer metodologias de trabalho úteis para subsidiar ações de planejamento e gestão desta complexa metrópole. Os estudos desenvolvem um procedimento com análise espacial realizado em ambiente SIG, o tratamento dasimétrico. O tratamento dasimétrico procura resolver certas incoerências do método coroplético, quando este é aplicado a bases censitárias, para isso conta com bases auxiliares de informação para melhor localizar a distribuição de densidade populacional. Tal procedimento é oportuno pois conta-se com considerável patrimônio cartográfico disponível para a área em estudo. Para dar coerência aos procedimentos realizados, faz uma revisão com um viés humanista, procurando entender o estado da evolução da Cartografia, posicionando a análise espacial em meio a outras linguagens, correntes cartográficas e suas discussões. / This research has as main purpose to develop types of demographic density representation from the Região Metropolitana de São Paulo (RMSP). Its believed that studies could establish useful work methodologies to subsidize planning actions and management of this complex metropolis. Studies develop a procedure with spatial analysis accomplished in GIS environment, the dasymetric treatment. The dasymetric treatment seeks to solve certain inconsistencies from choropleth method, when this is applied to a census basis, for this auxiliary basis of information is needed to better locate the distribution of population density. Such procedure is timely because it can count on considerable cartographic property available to the study site. To give consistency for performed procedures, revises with a humanistic bias, looking for understand the evolution status of Cartography, positioning the spatial analysis amid other languages, cartographic chains and their discussions.

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