17 research outputs found

    Spatiotemporal enabled Content-based Image Retrieval

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    Delineating Mixed Urban "Jobs-Housing" Patterns at a Fine Scale by Using High Spatial Resolution Remote-Sensing Imagery

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    The spatial distribution pattern of jobs and housing plays a vital role in urban planning and traffic construction. However, obtaining the jobs-housing distribution at a fine scale (e.g., the perspective of individual jobs-housing attribute) presents difficulties due to a lack of social media data and useful models. With user data acquired from a location-based service provider in China, this study employs a deep bag-of-features network (BagNet) to classify remote-sensing (RS) images into various jobs-housing types. Considering Wuhan, one of the fastest developing cities in China, as a case study area, three jobs-housing types (i.e., only working, only living, and both working and living) at the land-parcel level are obtained. We demonstrate that the multiscale random sampling method can reduce the influence of image noise, increase the utilization of training data, and reduce network overfitting. By altering the network structure and the training strategy, BagNet achieved excellent fitting accuracy for identifying each jobs-housing type (overall accuracy > 0.84 and kappa > 0.8). For the first time, we demonstrate that urban socioeconomic characteristics can be obtained from high-resolution RS images using deep learning techniques. Additionally, we conclude that the total level of mixing within Wuhan is not high at present; however, Wuhan is continuously improving the mixture of jobs and housing. This study has reference value for extracting urban socioeconomic characteristics from RS images and could be used in urban planning as well as government management.ISSN:1076-2787ISSN:1099-052

    Polycentricity and Sustainable Urban Form: An Intra-Urban Study of Accessibility, Employment and Travel Sustainability for the Strategic Planning of the London Region

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    This research thesis is an empirical investigation of how changing patterns of employment geography are affecting the transportation sustainability of the London region. Contemporary world cities are characterised by high levels of economic specialisation between intra-urban centres, an expanding regional scope, and market-led processes of development. These issues have been given relatively little attention in sustainable travel research, yet are increasingly defining urban structures, and need to be much better understood if improvements to urban transport sustainability are to be achieved. London has been argued to be the core of a polycentric urban region, and currently there is mixed evidence on the various sustainability and efficiency merits of more decentralised urban forms. The focus of this research is to develop analytical tools to investigate the links between urban economic geography and transportation sustainability; and apply these tools to the case study of the London region. An innovative methodology for the detailed spatial analysis of urban form, employment geography and transport sustainability is developed for this research, with a series of new application of GIS and spatial data to urban studies. Firstly an intra-metropolitan scale of spatial analysis is pursued, allowing both an extensive regional scope and a sufficiently intensive local level of detail to analyse the decentralisation processes described above. Secondly a series of detailed spatial datasets are introduced to analyse employment geography and dynamics, including business survey data and fine-scale real-estate data. For the measurement of accessibility, detailed network analysis and congestion data is used. Finally for the assessment of transportation sustainability, an indicator of CO2 emissions at intra-urban scales is developed, and is calculated for the 6.5 million journey-to-work trips in the study region. The results highlight extreme intra-urban variation in accessibility, employment geography and travel carbon emissions with clear relevance to urban form and sustainable travel debates in the London region

    Analysis of Land Use Change: Theoretical and Modeling Approaches

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    This Web Book provides information on basic concepts and trends in land use change, and then reviews the state of the art in land use theory and empirical modeling. It concludes by summarizing the main issues pertaining to theories and models of land use change, discusses selected issues in of a more general concern in the context of the analysis of land use change and outlines future research directions.https://researchrepository.wvu.edu/rri-web-book/1000/thumbnail.jp
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