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Spatial growth of informal settlements in Delhi: an application of remote sensing

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Slum development and growth is quite popular in developing countries. Many studies have been done on what social and economic factors are the drivers in establishment of informal settlements at a single cross-section of time, however limited work has been done in studying their spatial growth patterns over time. This…

Slum development and growth is quite popular in developing countries. Many studies have been done on what social and economic factors are the drivers in establishment of informal settlements at a single cross-section of time, however limited work has been done in studying their spatial growth patterns over time. This study attempts to study a sample of 30 informal settlements that exist in the National Capital Territory of India over a period of 40 years and identify relationships between the spatial growth rates and relevant factors identified in previous socio-economic studies of slums using advanced statistical methods. One of the key contributions of this paper is indicating the usefulness of satellite imagery or remote sensing data in spatial-longitudinal studies. This research utilizes readily available LANDSAT images to recognize the decadal spatial growth from 1970 to 2000, and also in extension, calculate the BI (transformed NDVI) as a proxy for the intensity of development for the settlements. A series of regression models were run after processing the data, and the levels of significance were then studied and compared to see which relationships indicated the highest levels of significance. It was observed that the change in BI had a higher strength of relationships with the change in independent variables than the settlement area growth. Also, logarithmic and cubic models showed the highest R-Square values than any other tested models.
ContributorsPrakash, Mihir (Author) / Guhathakurta, Subhrajit (Thesis advisor) / Myint, Soe W. (Committee member) / Aggarwal, Rimjhim (Committee member) / Arizona State University (Publisher)
Created2011
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Understanding open spaces in an arid city

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This doctoral dissertation research aims to develop a comprehensive definition of urban open spaces and to determine the extent of environmental, social and economic impacts of open spaces on cities and the people living there. The approach I take to define urban open space is to apply fuzzy set theory…

This doctoral dissertation research aims to develop a comprehensive definition of urban open spaces and to determine the extent of environmental, social and economic impacts of open spaces on cities and the people living there. The approach I take to define urban open space is to apply fuzzy set theory to conceptualize the physical characteristics of open spaces. In addition, a 'W-green index' is developed to quantify the scope of greenness in urban open spaces. Finally, I characterize the environmental impact of open spaces' greenness on the surface temperature, explore the social benefits through observing recreation and relaxation, and identify the relationship between housing price and open space be creating a hedonic model on nearby housing to quantify the economic impact. Fuzzy open space mapping helps to investigate the landscape characteristics of existing-recognized open spaces as well as other areas that can serve as open spaces. Research findings indicated that two fuzzy open space values are effective to the variability in different land-use types and between arid and humid cities. W-Green index quantifies the greenness for various types of open spaces. Most parks in Tempe, Arizona are grass-dominant with higher W-Green index, while natural landscapes are shrub-dominant with lower index. W-Green index has the advantage to explain vegetation composition and structural characteristics in open spaces. The outputs of comprehensive analyses show that the different qualities and types of open spaces, including size, greenness, equipment (facility), and surrounding areas, have different patterns in the reduction of surface temperature and the number of physical activities. The variance in housing prices through the distance to park was, however, not clear in this research. This dissertation project provides better insight into how to describe, plan, and prioritize the functions and types of urban open spaces need for sustainable living. This project builds a comprehensive framework for analyzing urban open spaces in an arid city. This dissertation helps expand the view for urban environment and play a key role in establishing a strategy and finding decision-makings.
ContributorsKim, Won Kyung (Author) / Wentz, Elizabeth (Thesis advisor) / Myint, Soe W (Thesis advisor) / Brazel, Anthony (Committee member) / Guhathakurta, Subhrajit (Committee member) / Arizona State University (Publisher)
Created2011
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Sustainability implications of mass rapid transit on the built environment and human travel behavior in suburban neighborhoods: the Beijing case

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The sustainability impacts of the extension of the Mass Rapid Transit (MRT) system in suburban Beijing are explored. The research focuses on the neighborhood level, assessing sustainability impacts in terms of greenhouse gas emissions, air pollution, and energy consumption. By emphasizing suburban neighborhoods, the research targets the longest commuting trips,…

The sustainability impacts of the extension of the Mass Rapid Transit (MRT) system in suburban Beijing are explored. The research focuses on the neighborhood level, assessing sustainability impacts in terms of greenhouse gas emissions, air pollution, and energy consumption. By emphasizing suburban neighborhoods, the research targets the longest commuting trips, which have the most potential to generate significant sustainability benefits. The methodology triangulates analyses of urban and transportation plans, secondary data, time series spatial imagery, household surveys, and field observation. Three suburban neighborhoods were selected as case studies. Findings include the fact that MRT access stimulates residential development significantly, while having limited impact in terms of commercial or mixed-use (transit-oriented development) property development. While large-scale changes in land use and urban form attributable to MRT access are rare once an area is built up, adaptation occurs in the functions of buildings and areas near MRT stations, such as the emergence of first floor commercial uses in residential buildings. However, station precincts also attract street vendors, tricycles, illegal taxis and unregulated car parking, often impeding access and making immediate surroundings of MRT stations unattractive, perhaps accounting for the lack of significant accessibility premiums (identified by the researcher) near MRT stations in suburban Beijing. Household-based travel behavior surveys reveal that public transport, i.e., MRT and buses, accounts for over half of all commuting trips in the three case study suburban neighborhoods. Over 30% of the residents spend over an hour commuting to work, reflecting the prevalence of long-distance commutes, associated with a dearth of workplaces in suburban Beijing. Non-commuting trips surprisingly tell a different story, a large portion of the residents choose to drive because they are less restrained by travel time. The observed increase of the share of MRT trips to work generates significant benefits in terms of lowered energy consumption, reduced greenhouse gas and traditional air pollution emissions. But such savings could be easily offset if the share of driving trips increases with growing affluence, given the high emission intensities of cars. Bus use is found to be responsible for high local conventional air pollution, indicating that the current bus fleet in Beijing should be phased out and replaced by cleaner buses. Policy implications are put forward based on these findings. The Intellectual Merit of this study centers on increased understanding of the relationship between mass transit provision and sustainability outcomes in suburban metropolitan China. Despite its importance, little research of this genre has been undertaken in China. This study is unique because it focuses on the intermediate meso scale, where adaptation occurs more quickly and dramatically, and is easier to identify.
ContributorsXie, Liou (Author) / Webster, Douglas (Thesis advisor) / Cai, Jianming (Committee member) / Pijawka, David (Committee member) / Guhathakurta, Subhrajit (Committee member) / Arizona State University (Publisher)
Created2012
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GeoAI-enhanced Techniques to Support Geographical Knowledge Discovery from Big Geospatial Data

Description
Big data that contain geo-referenced attributes have significantly reformed the way that I process and analyze geospatial data. Compared with the expected benefits received in the data-rich environment, more data have not always contributed to more accurate analysis. “Big but valueless” has becoming a critical concern to the community of…

Big data that contain geo-referenced attributes have significantly reformed the way that I process and analyze geospatial data. Compared with the expected benefits received in the data-rich environment, more data have not always contributed to more accurate analysis. “Big but valueless” has becoming a critical concern to the community of GIScience and data-driven geography. As a highly-utilized function of GeoAI technique, deep learning models designed for processing geospatial data integrate powerful computing hardware and deep neural networks into various dimensions of geography to effectively discover the representation of data. However, limitations of these deep learning models have also been reported when People may have to spend much time on preparing training data for implementing a deep learning model. The objective of this dissertation research is to promote state-of-the-art deep learning models in discovering the representation, value and hidden knowledge of GIS and remote sensing data, through three research approaches. The first methodological framework aims to unify varied shadow into limited number of patterns, with the convolutional neural network (CNNs)-powered shape classification, multifarious shadow shapes with a limited number of representative shadow patterns for efficient shadow-based building height estimation. The second research focus integrates semantic analysis into a framework of various state-of-the-art CNNs to support human-level understanding of map content. The final research approach of this dissertation focuses on normalizing geospatial domain knowledge to promote the transferability of a CNN’s model to land-use/land-cover classification. This research reports a method designed to discover detailed land-use/land-cover types that might be challenging for a state-of-the-art CNN’s model that previously performed well on land-cover classification only.
ContributorsZhou, Xiran (Author) / Li, Wenwen (Thesis advisor) / Myint, Soe Win (Committee member) / Arundel, Samantha Thompson (Committee member) / Arizona State University (Publisher)
Created2019