This study aims to create a detailed urban sprawl index, investigate the relationship between density and other urban sprawl factors, and analyze how these factors affect commuting mode time in South Korean cities using structural equation modeling and multiple linear regression. Urban sprawl factors are categorized from various individual perspectives into density, urban landscape, land-use mix, centeredness, and street connectivity. We show that while scores for urban landscape, density, and centeredness were high in cities with large populations, scores for land-use mix and street connectivity were high in cities with medium and small populations. We found that density had significant effects on urban landscape, centeredness, and street connectivity. The indirect effects of density on commuting modes and time counterbalance the direct effects, indicating that while the indirect effects do not change the direction of the direct effects, they reduce their magnitude, making the total effect smaller than the direct effect. A higher density was associated with fewer commuters using cars and higher numbers of public transit, but the reduction in cars was limited to less than 30 min of commuting time. In addition, high density was positively associated with commuting time. High scores for urban landscape, land-use mix, and street connectivity were associated with a reduction in commuting time but did not have an effect on the conversion from cars to public transit for the journey to work. High scores for urban landscape and street connectivity were associated with more walking commuters but were limited to commuting for less than 60 min. This study shows that urban sprawl factors are mutually complementary for commuting mode changes and time. This study provides evidence for establishing sustainable transportation plans. In addition, the urban sprawl index can be used in future research to investigate the effects of urban sprawl on various social and environmental phenomena.

中文翻译：

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量化城市扩张并调查城市扩张因素、通勤模式和时间之间的因果关系：以韩国城市为例


本研究旨在创建详细的城市扩张指数，调查密度与其他城市扩张因素之间的关系，并利用结构方程模型和多元线性回归分析这些因素如何影响韩国城市的通勤模式时间。城市扩张因素从不同的角度分为密度、城市景观、土地利用组合、中心性和街道连通性。我们发现，虽然人口众多的城市在城市景观、密度和中心度方面得分较高，但在中小人口城市中，土地利用组合和街道连通性得分较高。我们发现密度对城市景观、中心性和街道连通性有显着影响。密度对通勤模式和时间的间接影响抵消了直接影响，这表明虽然间接影响不会改变直接影响的方向，但它们会降低其幅度，使总影响小于直接影响。较高的密度与使用汽车的通勤者较少和公共交通数量较多有关，但汽车的减少仅限于通勤时间少于 30 分钟。此外，高密度与通勤时间呈正相关。城市景观、土地利用组合和街道连通性的高分与通勤时间的减少有关，但对上班途中从汽车到公共交通的转换没有影响。城市景观和街道连通性得分高与更多步行通勤者相关，但仅限于通勤时间少于 60 分钟。本研究表明，城市扩张因素对于通勤方式变化和时间是相互补充的。 本研究为制定可持续交通计划提供了证据。此外，城市扩张指数可用于未来的研究，以调查城市扩张对各种社会和环境现象的影响。