As urban areas exert profound pressures on the natural environment, driving significant resource consumption and waste production, designers need to rethink the way urban projects are being developed. Therefore, this article advances the operationalization of the Circular Urban Metabolism (CUM) framework by analyzing a design case study: the Promenade Nardal in Paris. While CUM integrates the systemic material flow analysis of Urban Metabolism with the restorative strategies of the Circular Economy, it remains limited in its spatial articulation and applicability at the scale of urban design. Through a mixed-methods approach combining Life Cycle Assessment, spatial analysis, and qualitative inquiry, the article compares two circular design strategies, associated with the reuse of paving stones and the recycling of glass to produce Misapor, with conventional alternatives. Results demonstrate that stone reuse reduced CO2 emissions, energy demand, and water use, while Misapor showed energy and water advantages but slightly higher CO2 emissions due to production and transport. Beyond quantitative metrics, the study reveals the distinct design efforts and institutional frictions induced by circular practices, especially reuse, which requires adaptive aesthetics, labor-intensive design, and negotiation with technical norms. By spatializing material flows and foregrounding design agency, the article refines CUM as a situated and scalable framework, highlighting the need for context-sensitive, materially differentiated strategies in circular urban design.

The shift from techno-centric to human-centric development is essential for smart cities to effectively leverage technological innovations and enhance the quality of life of citizens. Despite this recognition, there are limited studies that address the challenges and frame the conditions and impacts involved. This study employs a mixed-method approach, namely the combination of literature review, expert consultation, and case analysis, to investigate human-centered smart city development based on the example of Saudi Arabia. Drawing from the literature, it develops a conceptual framework that provides guidance for achieving human-centric smart cities. The findings indicate that while Saudi Arabia has achieved notable progress in smart city development, inclusivity, centralized planning, public engagement, capacity building, and data security hinder advancement. This study demonstrates that smart city initiatives must aim to go beyond mere buzzwords and integrate components in line with human values and societal expectations. The study’s findings may help in framing urban humanization policies aligned with of Saudi Arabia’s Vision 2030 and offer guidance for cities with similar contexts.

The primary goal of Transportation systems is to provide transportation accessibility to opportunities. Equitable access to essential destinations encompassing social, recreational, educational, and civic opportunities needs to be more consistent across different social groups. This study evaluates the disparities in social justice using social equity as a measure of transit access and walk access to non-work amenities. These non-work amenities include grocery stores, personal services, retail outlets, recreational venues, entertainment centers, and healthcare facilities in the U.S. Logistic regression models are developed using the 2017 National Community Livability Survey data. The results indicate regressive public transit access for socially disadvantaged groups, including older citizens, non-drivers, Medicare/Medicaid beneficiaries, and non-metropolitan residents. Walk access inequities similarly affect older individuals, non-drivers, the physically disabled, the unemployed, students, women, and non-metropolitan residents. This research emphasizes the importance of addressing transit and walk-access inequities to non-work amenities within transportation systems. By acknowledging the disparities in transportation equity, decision-makers and communities can foster more inclusive and equitable access to essential destinations, thereby promoting social cohesion and overall community well-being.

This research explores the visual and non-visual (circadian) perception of light in humans and their brain responses in the urban spaces of two contrasted cities: Madrid and Toledo, in Spain. Lighting has been demonstrated to induce the synthesis of neurotransmitters, which can function as regulators or disruptors of our biological system, causing diseases due to the alteration in our circadian rhythms; these responses are contingent upon the technical properties of the lighting (type of incidence, intensity, colour temperature, and primarily, wavelength), as well as the time and duration of exposure. In Madrid, we analyse Gran Vía, an iconic and busy avenue with high commercial and touristic activity. This has resulted in an excess of illumination, which has a notable impact on the night environment and, in particular, on the biology of the human beings who transit and inhabit these areas. In contrast to Toledo—a small, protected city (a UNESCO World heritage site since 1986) that has maintained a low population density, controlled commercial areas, and a low level of urban lighting at night—Madrid represents an opposite situation. In Madrid, measurements of both lux and light spectrum were taken to demonstrate the excessive light incidence, along with the high emission of short-wavelength light produced by LED screens, which, at night, disrupt our circadian cycle. This paper demonstrates how artificial light at night (ALAN) affects human circadian rhythms. Furthermore, this study suggests directions for urban lighting design, considering human circadian rhythms.

Rapid urbanization and climate change pressure cities to integrate sustainability, digitalization, and circular economy principles. Yet most existing approaches treat these agendas separately, leaving gaps in how urban infrastructures, governance, and data systems can jointly support circular transformations. This paper addresses this challenge by proposing and validating a Sustainable, Smart, and Circular City (SSCC) architecture that operationalizes the waste–energy–information nexus. The architecture is structured into seven interconnected layers—Physical, Digital, Analytical, Participatory Governance, Data Strategy, Innovation Management, and Assessment—and is tested through two integrated experiments in the Fenicia Urban Living Lab, Bogotá: (i) an AI- and drone-based system for waste detection and community reporting and (ii) a solar-powered IoT urban garden for environmental monitoring. These experiments demonstrate how digital twins, participatory governance, and multi-actor collaboration can activate circular strategies while enabling evaluation against international standards (ISO 37106, U4SSC, LEED). The results confirm that the SSCC model can transform siloed services into integrated, circular functions that enhance quality of life, productivity, and ICT-based sustainability. The originality of this study lies in validating an SSCC architecture that incorporates the waste–energy–information nexus across seven layers and demonstrates, through Urban Living Lab experimentation, how such an architecture can guide the transition from Smart Sustainable Cities to Circular Cities.

The rise of independent travel is reshaping tourism, moving away from mass tourism and rigid itineraries toward flexible, technology-driven, and sustainable experiences. This study examines how self-guided digital tours can reduce congestion at points of interest while maintaining visitor engagement. Using a stylized agent-based simulation implemented with the Mesa framework, we modeled guided and self-guided tourist groups to compare congestion patterns, travel flows, and completion rates. The results indicate that self-guided tours flatten congestion peaks and support decentralized, walking-based exploration while maintaining comparable engagement levels. The findings suggest that digital self-guided formats can complement urban visitor management and smart-city strategies by distributing tourist flows more evenly. Future research should calibrate the model with real-world data and case studies to validate and extend these results. This study contributes to the discourse on sustainable urban tourism by positioning self-guided tours as a tool for integrating visitor management into smart infrastructure and enhancing long-term cultural and environmental resilience.

This article explores psychological security in relation to the urban environment, analyzing its connection to people’s homes. The aim is to examine the psychological security of urbanites residing in different types of dwellings. A sample of 233 residents from the city of Yekaterinburg with similar characteristics participated in this study. The authors utilized the Methodology for Measuring Psychological Security of Urban Dwellers devised by O.Yu. Zotova and L.V. Tarasova. A questionnaire was used to document the respondents’ demographic information. It was found that the characteristics of a person’s home are associated with their level of psychological security. This study revealed differences in the private and overall indicators of psychological security among residents of Yekaterinburg living in various types of housing. This is associated with how strongly city residents perceive the reliability of the urban environment and the trustworthiness of relationships within the city. The results suggest that the psychological security of a city dweller is closely linked to the features of their immediate surroundings. The findings can be used by environmental psychologists to evaluate the quality of life of the urban population and create a more comfortable environment by taking into account the needs of people and designing objects that consider their emotional state.

The rapid adoption of electric vehicles (EVs) has intensified the demand for intelligent, scalable, and interoperable charging infrastructure. Traditional EV charging networks based on the Open Charge Point Protocol (OCPP) face challenges related to dynamic load management, cybersecurity, and efficient integration with renewable energy sources. This paper presents a novel AI-driven framework that integrates federated learning, predictive analytics, and real-time control within OCPP-compliant networks to enhance performance and sustainability. The proposed system utilizes edge AI modules at charging stations, supported by a central aggregator that employs federated learning to preserve data privacy while enabling network-wide optimization. A case study involving simulated smart charging stations demonstrates significant improvements, including an 18% reduction in peak load demand, a 29% increase in forecasting accuracy (MAPE of 8.5%), a 10% decrease in average charging wait times, and a 12% increase in on-site solar energy utilization. The framework’s compatibility with OCPP and related standards (e.g., IEC 61851, ISO 15118) ensures ease of deployment on existing infrastructure. These results indicate that the proposed AI-OCPP integration provides a scalable and intelligent foundation for next-generation EV charging networks that align with the goals of sustainable transportation and smart grid evolution.

Land use and land cover change (LUCC) is central to regulating human–land relationships and crucial for urban planning and sustainable development in arid oasis cities. As a typical oasis city in Xinjiang, Shihezi City faces the triple challenges of agricultural protection, urban expansion, and ecological conservation. Taking Shihezi City as the research object, this study used the 30 m resolution China Land Cover Dataset and applied the land use dynamic degree, comprehensive index of land use degree, transfer matrix, Geodetector, and PLUS model to analyse the spatiotemporal dynamics of LUCC from 2002 to 2022, identify driving mechanisms, and predict the land use pattern from 2027 to 2032. The results showed that (1) from 2002 to 2022, farmland decreased by 86.1075 km2, man-made surfaces increased by 63.7389 km2 (annual expansion rate of 2.86%), grassland slightly increased by 24.5592 km2, and other land types remained stable; (2) the dynamics of land use showed a phased characteristic of “growth–equilibrium–acceleration”, and the land use degree index rose to 2.8639; natural factors (elevation, soil, temperature) dominated LUCC, and most interactions among factors showed enhancement effects; (3) the PLUS model predicted that by 2032, farmland would decrease to 224.347 km2 and man-made surfaces would increase to 111.941 km2. This study clarifies the laws of LUCC in Shihezi, demonstrates driving analysis and simulation prediction, and provides scientific support for balancing urban development, agricultural protection, and ecological security in arid oasis regions.

Forgotten spaces, often referred to as lost spaces or non-places, represent a crucial challenge in contemporary urbanism and sustainable urban development. They are underdeveloped and undesirable urban areas that are in urgent need of rethinking, replanning, and redesign. They are mostly undefined, lacking measurable boundaries and communication routes. These natural areas are usually neglected and underutilized, which leads to their insufficient exploration from an urban-ecology perspective. Due to the impacts of climate change, it is necessary to reintegrate these lost places into urban planning. In organized non-spaces, it is crucial to rediscover their function and make these areas accessible or released for use. Wetlands, rich in biodiversity in urban areas and subject to seasonal changes, are threatened by human activity, and their protection is essential for the sustainable development of cities and urbanism today. Cities are interwoven with such non-places, which exhibit various characteristics within the urbans system. In conclusion, unrecognized urban spaces and lost wetlands represent an untapped potential for sustainable urban ecosystem development. This shifts the perception of urban voids from traditional urbanization towards their new potential as spaces for green development within the framework of sustainable contemporary cities.