The analysis and evaluation of urban structure are important while considering sustainable urban policies. It is necessary to develop a method that can easily analyze the social dynamics that are the result of changes over time in urban transportation and land use. Therefore, by describing the relationships between various agents in urban areas as a network, it is possible to analyze them by focusing on their structures. However, since there are few existing studies on social dynamics using network-based methods, it is necessary to examine the validity and effectiveness of these methods. The purpose of this study is to examine the possibility of urban analysis and evaluation focusing on the network shape by describing the urban activities and modeling the dynamics with a multilayer network. In particular, we focus on household composition and individual facility access, examine what kind of interpretation is possible for network indicators, and mention the applicability of complex networks to urban analysis. The model was applied to a two-dimensional grid virtual city, and the household composition and individual facility accessibility were quantified using the centrality index.

To ensure children’s safe independent mobility on the road, they need to learn basic traffic rules. In this case, traffic rule education in a realistic environment through a play-way method can be a significant learning strategy. This research focuses on the “Traffic Park (TP)”, which provides that opportunity. Specifically, this research examined how elementary school children’s knowledge of traffic rules and behavioral intentions are influenced by their experiences of using and playing in a TP before and after they start school. Children from four different elementary schools (grades 1~6) were surveyed in Toyohashi City, Japan using a web-based questionnaire survey. Structural equation modeling (SEM) was applied to analyze the effect of TP use experience on children’s awareness of traffic rules and behavioral intentions. Three distinct SEM models were tested to measure the effect pattern of children’s TP use experience on their traffic rule awareness and behavioral intentions. The results show that TP use experience before entering school has a statistically significant effect on children’s traffic rule awareness (β = 0.16, p < 0.004; model 1) and behavioral intention improvement (β = 0.09, p < 0.07; model 2). However, TP use experience after entering school was found to have no significant effect. Finally, children’s TP use experience indirectly improves their behavioral intentions (β = 0.74, p < 0.001; model 3) by improving their awareness of traffic rules. Overall, the findings of this study highlight the contribution of TPs in promoting children’s safe independent mobility and fostering the development of sustainable child-friendly cities worldwide.

Considering the rapid integration of digital services into daily life, it is crucial to analyze the impacts of the substitutability of physical services with digital alternatives. Limited studies have been conducted to investigate the relationship between service substitution and social networks and assess their impact on urban structure. Therefore, this study fills the gap by investigating how digital service substitution and social networks influence residential location choices and urban structure, aiming to support future sustainable urban modeling and planning tools. The study, through a comprehensive analysis incorporating cluster analysis, factor analysis, and binomial logistic regression on a web-based questionnaire survey (n = 6210), finds that socio-demographic factors significantly influence digital alternatives, and that digital service substitution and social networks impact sustainable urban structure. Younger individuals showed significantly higher adoption of digital alternatives, with age negatively associated with relocation likelihood. In urban areas, each additional year of age reduces the likelihood of relocation by approximately 4.4%, and individuals with high shopping substitution are 3.12 times more likely to consider relocation. These findings suggest that urban planners and policymakers to balancing physical and digital service provision to maintain a higher quality of life aligned with the SDGs and ensure sustainable urban development.

Evaluation of an individual’s accessibility to urban services is crucial for urban planners and policymakers to assess various urban policies and scenarios. Most studies have emphasized accessibility in physical spaces, with limited attention to the role of Information and Communication Technology (ICT) in providing virtual access and its implications for quality of life (QOL) and sustainability. This study addresses this gap by examining the substitutability of physical activities with digital alternatives and their potential contribution to decarbonization. Using data from an online questionnaire survey in Japan, we analyze how individuals access services across both transportation and ICT networks. We propose an integrated evaluation framework that measures QOL by considering accessibility in both physical and virtual spaces. The analysis highlights differences in substitutability across activities such as shopping, working, schooling, and entertainment, while revealing that services like healthcare and physical tourism remain less substitutable. The results disclose that accessibility strongly influences individuals’ adoption of digital alternatives, which in turn offer significant benefits in terms of convenience and environmental impact. The proposed methodology provides valuable insights seeking to balance physical and virtual service accessibility, supporting sustainable urban development in line with UN Sustainable Development Goals 10 and 11.

The reduction in locational traffic accident risks through appropriate traffic safety management is important to support, maintain, and improve children’s safe and independent mobility. This study proposes and verifies a method to evaluate the risk of elementary school students-vehicle accidents (ESSVAs) at individual intersections on residential roads in Toyohashi city, Japan, considering the difference in travel purposes (i.e., school commuting purpose; SCP or non-school commuting purpose: NSCP), based on a statistical regression model and Empirical Bayes (EB) estimation. The results showed that the ESSVA risk of children’s travel in SCP is lower than that in NSCP, and not only ESSVAs in SCP but also most ESSVAs in NSCP occurred on or near the designated school routes. Therefore, it would make sense to implement traffic safety management and measures focusing on school routes. It was also found that the locational ESSVA risk structure is different depending on whether the purpose of the children’s travels is SCP or NSCP in the statistical model. Finally, it was suggested that evaluation of locational ESSVA risks based on the EB estimation is useful for efficiently extracting locations where traffic safety measures should be implemented compared to that only based on the number of accidents in the past.