Measuring the evolution of urban morphology remains challenging, with dynamic approaches for capturing overall spatial evolution are still limited. Directional measurement is essential, offering a macro-level lens that links urban form evolution relative to overall historical patterns and captures the underlying spatial heterogeneity of urban expansion. Here, we introduce a directional expansion index (DEI) to quantify the directional dynamic characteristics of urban expansion relative to historical pattern based on vectorial properties. Using the DEI, three distinct types of expansion are identified, and two variants are developed to enable multi-scale quantification of directional characteristics from a bottom-up perspective. Moreover, an adaptive clustering approach is employed to reveal directional heterogeneity through dynamic rather than single-scale partitioning. The DEI was demonstrated in the Wuhan metropolitan area (China) from 1995 to 2020. Our findings reveal that the directional expansion pattern of the Wuhan metropolitan area was becoming increasingly homogeneous and compact. Based on the employed clustering algorithm, the multi-scale partitions retain significant independent characteristics at the micro scale while containing macro-scale homogeneous characteristics simultaneously. By comparing with a representative dynamic index, we demonstrate that DEI expands the characterization dimensions by filling the gap in measuring expansion compactness from the perspective of directional heterogeneity.
This paper shows that global skyscraper construction both accelerated and globalized after the 2001 attacks on the Twin Towers in New York, into the twenty-first century. Despite being increasingly incorporated into the global economy as a ‘new frontier’ for global investors, Sub Saharan Africa (SSA) did not share in this construction boom. This paper demonstrates that the absence of skyscrapers in SSA is an empirical puzzle. The key drivers of skyscraper construction – economic growth, population increase and migration, globalization, and vanity-driven competition – should all be pushing SSA into building upwards. The key to resolving the empirical puzzle of why SSA doesn't build skyscrapers lies in land markets: better functioning land markets would directly increase the supply and indirectly increase the demand for skyscrapers. This paper suggests a mechanism to allow city governments to focus their capacity on protecting the property rights of developers building skyscrapers, allowing a skyscraper project to be granted the status of a standalone Special Economic Zone (SEZ). The resulting construction of skyscrapers may simply increase the supply of luxury residential accommodation and office space and displace any pre-existing informal construction to a less advantageous location on the city periphery. The demand for formal residential accommodation is also influenced by more than price – culture matters. Consequently, the paper concludes by noting that inclusive or affordable housing construction needs to be rooted in a more holistic development strategy.
This mixed-methods case study evaluates Iran's Smart Schools Project in Zahedan, a socioeconomically heterogeneous city, to identify barriers and scalable interventions for technology-enhanced schooling in resource-constrained contexts. Data comprise structured surveys (n = 150), semi-structured interviews with policymakers (n = 10), and classroom observations across urban, semi-urban and rural schools. Findings reveal stark infrastructure and access gaps (rural device-sharing 1:175; chronic power outages; intermittent urban connectivity). Targeted, low-cost interventions (solar microgrids, offline learning-management systems, and Raspberry Pi deployments) produced measurable gains (rural literacy +25%; STEM engagement +18%). Cultural resistance was substantially reduced through engagement with religious leaders, raising parental approval from 20% to 65%. Analysis is situated within TPACK (Technological Pedagogical Content Knowledge) and SAMR (Substitution, Augmentation, Modification, Redefinition) frameworks. Policy implications include tiered funding that prioritizes rural allocation (proposed 60% share), promotion of domestic low-cost device manufacturing, and decentralized, context-sensitive teacher training. The study demonstrates that equity-driven, culturally attuned strategies can align national smart-school ambitions with local realities, offering a replicable model for other resource-limited regions seeking to close the urban–rural digital divide.
With the advancement of modern lighting technologies, widespread light pollution has become a significant environmental hazard. The ecotoxicological effects of ALAN on the urban aquatic environment have long been overlooked, despite substantial scientific focus on terrestrial and atmospheric environments. The impacts on aquatic organisms and ecosystem functions are highly complex and variable. This review compiled the ecotoxicological effects of ALAN on aquatic environments, from ecological processes to individual responses. We examined how ALAN influences key aquatic species, such as fish, algae, and zooplankton, by causing cascade effects on community composition, food webs, habitat integrity, nutrient cycles, and energy flow. We also detailed how ALAN interacts with other environmental stressors, including chemical pollution and global warming. Notably, we highlighted laws and policies addressing light pollution across different countries. Finally, we identified and proposed future research directions to improve the understanding of light pollution in urban aquatic ecosystems, aiming to clarify its profound impacts and to offer science-based recommendations for nighttime lighting management.
This study conceptualizes university campus open spaces as socio-ecological systems and develops an integrated evaluation framework combining spatial elements, ecological services, and adaptive capacities. Addressing the tendency for campus open spaces to be assessed through site-specific criteria, the study applies a resilience-based urban systems perspective to capture the interdependencies among environmental, spatial, and functional performance attributes. Using a case study at a Hong Kong university campus, questionnaire-based surveys were conducted with 220 users across ten open-space types, and Structural Equation Modelling (SEM) was employed to examine how perceived importance of performance attributes shapes satisfaction with different open-space settings. The results reveal two distinct satisfaction pathways. For passive open spaces (courtyards, cafés, squares), satisfaction is predominantly driven by spatial elements (β = 0.507), indicating that perceptions of openness, scale, and aesthetic quality play a decisive role in shaping user experience, with ecological services exerting an indirect influence through spatial elements. In contrast, satisfaction with active open spaces (sport places) is primarily shaped by adaptive capacities (β = 0.268), such as accessibility, safety, and sociability, reflecting a more function-oriented appraisal. Across both pathways, ecological services emerge as a foundational dimension, significantly influencing spatial elements and adaptive capacities, and being directly associated with satisfaction in ecologically intensive settings such as rooftop gardens. By revealing differentiated satisfaction mechanisms and their structural relationships, this study advances the understanding of campus open spaces as integrated and resilient systems. The findings provide actionable guidance for campus planning and management, suggesting that investments should prioritize spatial quality in passive spaces while emphasizing functional accessibility and safety for active environments.
Smart city indexes increasingly influence urban governance, policy benchmarking, and investment narratives, yet their conceptual evolution remains insufficiently examined. This article investigates how major smart city evaluation frameworks changed between 2017 and 2022 through a longitudinal thematic analysis of six prominent smart city indexes selected from an initial inventory of sixteen. The findings suggest a shift in the smart city index landscape from more technocentric assessment frameworks toward more integrated evaluation logics that give greater attention to governance capacity, economic conditions, and societal dimensions.
From being infrastructure utilities, urban underground spaces (UUS) have developed into multipurpose public spaces that combine commercial, cultural, and transit functions. While their technical and spatial contributions to compact urbanism are evident, their capacity to foster conviviality, the experiential quality of inclusiveness, sociability, and shared belonging, is less understood. This study develops and empirically tests a conceptual framework that operationalizes conviviality in UUS by linking seven spatial-perceptual dimensions (safety and security, identity and meaning, accessibility, functionality, environmental comfort, aesthetics, and structure and form) to behavioral mediators of willingness to use and social interaction, culminating in perceived conviviality. Using the Theatre-Shahr underground complex in Tehran as a case study, data were collected through structured surveys and analyzed via Partial Least Squares Structural Equation Modeling (PLS-SEM). The findings indicate that although environmental factors generally have a positive indirect effect on perceived conviviality, social interaction emerges as the primary mechanism shaping conviviality in urban underground spaces, while willingness to use plays only a complementary and limited mediating role in this process. Among the environmental factors, accessibility, environmental comfort, and safety and security show the strongest effects. In contrast, some variables, particularly identity and meaning and structure and form, do not demonstrate statistically significant effects in certain pathways. These findings suggest that planning and design strategies for urban underground spaces should prioritize environmental qualities that support social interaction, to enhance perceived conviviality.
Riyadh's greenhouse gas emissions and urban climate risks are likely heightened by accelerated urbanization and profound dependence on private cars. Despite the government's investment in public transportation, societal resistance to giving up private cars and using public transit persists due to cultural and traditional factors. Within the Gulf context, this study is the first to investigate the unique socio-cultural and urban context of Riyadh to understand university students' mobility behavior, identify four factors that significantly are associated with their travel choices, and quantitatively rank the relative influence of these factors. Surveys (n = 710) were used to assess four key factors, analyzed via multiple regression, chi-square, and t-tests. Results indicate that, in descending order of influence, psychological factors (explaining 23% of the variance) have the most significant association with students' willingness to switch to public transport in Riyadh, followed by trip characteristics (13%), urban factors (12%), and socioeconomic and demographic factors (12%). The result suggests that, alongside infrastructure improvements, coordinated strategies are required to change social norms, enhance environmental awareness, and create culturally responsive incentives. The findings support the implementation of place-based policies for sustainable mobility.
Studying the long-term migration network within cities effectively reveals changes in urban spatial structures. This paper focuses on intra-city migration activities, introducing a method for dynamic network construction and analysis based on spatiotemporal data, offering a new perspective for examining the dynamic characteristics of residential migration within cities and their relationship to urban development. Migration behaviors are aggregated at the community level in the form of migration flows, and a time-varying network model of migration flows is constructed. Community detection and dynamic evolution analyses are conducted to uncover migration behavior characteristics. Using Shenzhen, a megacity in China, as a case study, a migration network spanning six consecutive years (2018–2023) was constructed using mobile phone signaling data. Our findings reveal that the gravitational pull of communities in the northern and eastern sub-center areas has increased. The dynamic evolution of community structures is closely related to the city's polycentric structure. Smaller network communities are more susceptible to changes, while strengthened regional connections have led to community mergers. The time-varying migration network proposed in this study provides an effective method for observing the development patterns of urban spatial structures from a mesoscopic perspective by tracking and analyzing migration flow patterns between different areas within a city.
In an increasingly uncertain global environment, the resilience of city networks has become a key indicator of regional stability and adaptability. This paper examines four mega-city regions in China by constructing two ownership-segmented city networks based on state-owned enterprises (SOEs) and privately owned enterprises (POEs). Comparative analysis of their structures and resilience performance reveals systematic “resilience asymmetry” associated with ownership logics. Both networks display a basic center–periphery pattern, but with distinct configurations and shock responses: SOE-based networks form highly centralized, radiating structures with strong resource integration, exhibiting a “weaker resistance—faster recovery” trajectory; POE-based networks exhibit multi-centered, proximity-based structures with greater initial resistance but slower recovery, showing a “stronger resistance—slower recovery” trajectory. These findings highlight that ownership-driven network structures each possess unique resilience advantages. The paper contributes by advancing the concept of resilience asymmetry and suggesting that future governance should foster more compound and adaptive network configurations.
This essay argues that the most consequential question for AI in architecture is not whether AI can generate buildings, but whether it can be guided toward designs that are coherent, beautiful, and supportive of human life. To move past the present impasse of style-driven generation, the essay develops a Living Structure + AI paradigm grounded in Christopher Alexander's theory and operationalised through a skeleton–skin workflow. The skeleton encodes hierarchical order through nested substructures and computable indicators — the L-score and the B-score produced by the Beautimeter; the skin is generated by AI under structural constraint. The paradigm is illustrated through four real renovations on the HKUST(GZ) campus and connected to recent — and still preliminary — results in which large language models, properly prompted, judge architecture in broad agreement with public preference and with measured brain responses. AI for architecture, on this account, is less about spectacle than about the quiet, demanding work of structural diagnosis and structurally constrained generation.
This paper presents a comprehensive legal and qualitative analysis of Florida's Community Redevelopment Agencies (CRAs), focusing on their compliance with state law and their effectiveness in addressing urban blight. Since the enactment of the Florida Redevelopment Act of 1969, CRAs have played a vital role in urban renewal, economic development, and the provision of low-to-moderate income housing across the state. Despite their widespread adoption concerns persist regarding their accountability, transparency, and susceptibility to political influence. The objective of this research then is to understand if the criticism of CRAs, not living up to their legislative requirements especially as it pertains to the misuse of taxpayer funds holds weight. Through a systematic review of Agency websites and redevelopment plans, the study evaluates seven key legislative requirements. The findings reveal significant variability in CRA performance, with many agencies failing to meet basic statutory standards and a majority operating with outdated redevelopment plans. The analysis highlights systemic issues in oversight and governance, suggesting that poor compliance with minor requirements may indicate broader challenges in fulfilling major legal obligations. The paper concludes by recommending enhanced accountability measures and targeted legislative reforms to ensure CRAs effectively serve their intended public purpose.
This study examines the effectiveness of public transportation maps in Indonesia cities by evaluating both user perceptions and compliance with recognized mapping standards. Utilizing data from user surveys and secondary data, it analyzes key design elements, such as station naming conventions, schematic line diagrams, typography, color contrast, and the depiction of landmarks to create a seamless wayfinding. The results reveals significant inconsistencies in map clarity and accessibility, as well as a lack of standardization across major cities like Yogyakarta, Jakarta, Surabaya and Bandung. Based on these findings, the study proposes a unified set of design standards for transit maps – aiming to improve usability for people with disabilities, facilitating easier navigation for all users, and aligning Indonesia's transit maps with international best practices. The propose standards are intented to support more coherent, accessible, and user-friendly public transportation systems, thereby contributing to enhanced transportation infrastructure, intersectional equity and sustainable urban mobility.
The outbreak of COVID-19 significantly reduced the use of public transportation. Due to the changes in the epidemic development, transport volume decreased when the epidemic was severe, and when the epidemic eased, the transport volume rebounded. This study used data from the Ministry of Transportation's Statistical Query Network and government open platforms to observe the impact of COVID-19 on the volume of public transportation at different times and to different degrees. This study explored mass transportation volume trends of a variety of public transportation systems in the post-epidemic era and used a Prophet-based time series model to evaluate ridership trends. Five types of resilience indicators were created to classify type of ridership recovery, including proportion of ridership drop and recovery, average ridership decline and recover rate, and time to recovery. Furthermore, it provides traffic volume forecasts and offers specific operational recommendations based on data analysis. This research contributes to the understanding of travel behaviors in various parts of Taiwan during and after the epidemic and specific operational suggestions through data forecasts, providing practical references for policy makers and relevant operating units so that more efficient transportation capacity allocation and use can be made in the future.
Urban shrinkage and aging exhibit complex interactions in population spatial redistribution. However, existing studies largely remain descriptive and correlation-oriented, and lack a systematic theory of spatial coupling and mechanism analysis. This study constructs a spatial coupling theoretical framework centered on the direct and indirect effects of young workforce relocation. Using data from 142 county-level units in the Chengdu-Chongqing Economic Circle of China from 2010 to 2020, the study employs bivariate LISA and OPGD models to analyze and verify the spatial coupling process and mechanisms. The results indicate that: (1) Urban shrinkage and aging theoretically constitute a reinforced bidirectional spatial coupling mechanism through the direct relocation of the young workforce and its indirect socioeconomic and functional impacts. (2) Empirically, under the “core-periphery” pattern, the two processes intensify synchronously, with a Moran's I of 0.558, significant High-High and Low-Low clustering, and bidirectional factor explanatory power exceeding 0.3, indicating a significant spatial coupling effect. (3) Mechanism analysis further confirms that young workforce relocation represents the core logic driving coupling evolution. This coupling process is simultaneously shaped by population structure heterogeneity, regional labor division, public service disparities, and ancestral culture. This study advances theoretical understanding of urban shrinkage-aging interactions and offers a new analytical perspective for integrated governance.
