Search Results (1,883)

This article summarizes the results of a demand-and-supply analysis of hydrogen road transport development in Poland, conducted as part of a research project at the Motor Transport Institute in 2025, with a time horizon extending to 2040. The central aim of the study is to identify optimal hydrogen refueling station locations and develop a phased deployment plan. It also assesses the potential for using hydrogen as an alternative transport fuel in Poland compared with other European countries. The article presents a multi-criteria decision-making model developed to support the planning of hydrogen infrastructure for the Polish transport system. The model’s assumptions and the research results concerning the selection of hydrogen refueling station locations in large cities are discussed. Technical, ecological, logistical, legal, and social aspects related to the implementation of hydrogen infrastructure are analyzed. The article also outlines methods for parameterizing and assessing the potential for hydrogen adoption in transport. Forecasts indicate that the development of a hydrogen vehicle fleet could contribute to improved public health, sustainable development, and a reduction in the negative effects of high emissions. The objective of the research is to determine the environmental and energy-transition impacts of shifting from combustion-powered transport to hydrogen over the coming decades. The study introduces an innovative modeling approach, as previous research has not examined city rankings and urban mobility plans with comparable depth to identify, structure, and weight the criteria used for selecting optimal hydrogen refueling station locations. Although independent validation remains unattainable due to the absence of certain operational data, the study’s findings can support transport, energy, and climate strategies, with robustness defined strictly as internal stability and cross-method consistency. Full article

A key aspect of sustainability is regenerating inhabited urban areas without demolishing them, since this helps retain the embodied carbon and spatial capital built up in existing buildings while preventing the displacement that results from clearing land. In this approach, which prioritises retention, a major issue when reviving a district is where the first intervention should take place. The usual method is to map out ‘readiness’—a combination of accessibility, public transport facilities, and current levels of activity—and then focus interventions on areas where this criterion is highest. Yet because readiness is evaluated in terms of existing assets, it tends to identify streets that are already working well, and these are also the ones with the least potential for further improvement. This study measures the part of a district which has so far been left unused. The latent field of a district consists of streets that are highly accessible within the larger city network but are not recruited by routes connecting the district’s specified supra-local destinations. The shape of this latent field, whether in the form of long lines or scattered patches, remained stable across the tested threshold and generator-inventory perturbations, whereas its size mainly reflects the modelling assumptions. The practical consequences of this approach are evident in the ISKRA creative-district project, situated in the historic part of Toruń, Poland. Placed at the point of peak readiness, the insertion model brings 11% of the target rib onto the route skeleton; the same generator 500 m along the rib brings 70%. A similar intervention carried out in a different location has no effect. Activation is not related to distance, but it is limited by distance. When applying the method to Toruń’s Old Town, the resulting latent field comprises areas rather than lines, showing that a different intervention strategy is needed. The method requires only an open street network, a list of the main district destinations, and a commitment to preserving the existing urban structure; it generates siting predictions that can be tested using pedestrian counts. Full article

Despite the rising interest in examining factors associated with body mass index (BMI), little longitudinal evidence can be found regarding its associations with the built environment (BE) and commute, which are closely related to sustainable urban development. Employing two rounds of nationwide survey data in China, this research assesses the links between BE, commute, and BMI in both cross-sectional and longitudinal ways. The findings indicate that non-motorized commute duration is negatively associated with BMI in both analyses. Switching from non-motorized to motorized modes is positively associated with BMI change, whereas switching in the opposite direction is negatively associated with BMI change. Among BE factors, increases in density, diversity, and green coverage are negatively associated with BMI change. Additionally, the research highlights the role of urbanization and suggests a nonlinear association with BMI that is consistent with an inverted-U pattern. The findings highlight the potential relevance of non-motorized commuting to overweight prevention and sustainable mobility. This research provides implications for integrating transport planning, public health, and sustainable urban development. Full article

Rural low-carbon planning requires evaluation tools that connect carbon-related performance with the ecological, socioeconomic, and infrastructure conditions of rural settlements, yet carbon inventories and conventional human-settlement assessments do not fully integrate these dimensions. This study developed an exploratory carbon-benefit-oriented sustainability diagnostic and applied it to Qingge Village, Fujian Province. Fuzzy Delphi screening retained 27 indicators across ecological, social, production, and engineering subsystems; Delphi consultation generated expert-based weights; a dimensionless ratio transformation standardized the indicator values; threshold, standardization, and weighting sensitivity analyses evaluated the stability of results across analytical specifications. The primary composite score was 0.413 compared with 0.590 under the target-achievement transformation, and both expert-weighted transformations ranked subsystem contributions as production, ecological, social, and engineering. The ecological and production subsystems performed more strongly against the selected references than the social and engineering subsystems, whereas fully equal global weights placed ecology ahead of production. The principal diagnostic priorities were household energy emissions, green agricultural upgrading, public-transport access, and recorded energy-efficient building coverage. These findings indicate that the diagnostic can organize village-scale low-carbon planning priorities and translate multidimensional performance evidence into a sequenced set of spatial improvement options. This study therefore provides a transparent and practically applicable approach for linking carbon-related indicators with rural human-settlement planning and supporting evidence-informed low-carbon revitalization. Full article

This perspective examines the interactions among microplastics (MPs), emerging contaminants (ECs), climate change, and extreme hydrological events. Droughts, water scarcity, heatwaves, intense rainfall, and floods can alter the occurrence, mobilisation, transport, fate, and risks of MPs and associated ECs across water, soil, and groundwater systems. The analysis focuses on the context-dependent potential of MPs to act as vectors of ECs, soil–water interactions, and the potential influence of MPs on greenhouse gas (GHG) emissions. When these stressors co-occur, their combined effects may be additive, synergistic, or antagonistic. Accordingly, the “perfect storm” framing is used here to describe the potential for mutually reinforcing and cascading risks rather than to imply that synergy occurs universally. An integrated perspective therefore helps anticipate worst-case scenarios and move beyond the fragmented assessment of individual stressors. This paper discusses sustainable mitigation and adaptation strategies, including advanced wastewater treatment, water reuse, climate-resilient water management, infrastructure adapted to increasing hydrological variability, climate-smart agriculture, and safer alternatives to conventional plastics and chemicals. Effective implementation combines technological innovation with monitoring, governance, policy action, and public awareness. By framing the microplastics–contaminants–water–soil–climate nexus as an interconnected sustainability challenge, this work aims to support environmental resilience and progress toward the Sustainable Development Goals. Full article

New Light Rail Transit (LRT) systems are frequently promoted as a means of reducing car dependence and supporting urban sustainability; however, their effectiveness depends on how different traveller segments respond to LRT relative to competing modes. This study examines whether car owners and non-car owners exhibit distinct preference structures and policy sensitivities towards a proposed LRT system in Kerman, Iran. A stated-preference mode-choice survey conducted in November 2023 generated 1916 valid choice observations, including 955 observations from car owners and 961 from non-car owners, based on 736 completed questionnaires. Multinomial Logit (MNL), Nested Logit (NL), and Mixed Logit (MXL) models were estimated separately for each segment. Policy implications were assessed using elasticities, marginal effects, and scenario-based simulations. The results show that, for car owners, the MXL specification provides a slightly better statistical fit, indicating modest preference heterogeneity, while the main behavioural conclusions remain consistent across model structures. For non-car owners, the NL model performs best, revealing clearer substitution between public-transport modes (bus/LRT) and on-demand services (taxi/ride-hailing). Although LRT shows a negative baseline preference, particularly among car owners, its uptake increases substantially with improved LRT travel-time performance and higher private-car operating costs. Overall, improving LRT travel-time competitiveness is critical for both groups, while attracting car owners additionally requires coordinated measures that raise the generalised cost of private-car use and strengthen the relative advantage of LRT. These findings highlight the importance of segment-sensitive policy design for maximising the contribution of LRT to sustainable urban transport and long-term urban sustainability. Full article

The deployment of hydrogen-powered public transport requires operators to decide not only whether to adopt fuel-cell buses, but also how hydrogen should be supplied. This study compares two sourcing strategies, as follows: on-site hydrogen production (Make) and external procurement (Buy). An operator-centered framework combining Levelized Cost of Hydrogen (LCOH) and Total Cost of Ownership (TCO) is applied to two Italian cases, using project-specific procurement and technical data from Monfalcone/Gorizia and Ferrara together with explicit modeling assumptions. Under base-case assumptions, Make yields an LCOH of €13.67/kg H₂ and a fleet TCO of €2.34/km, compared with €2.51/km for Buy at a delivered green hydrogen price of €12/kg. The deterministic break-even price is €10.25/kg, while both hydrogen configurations remain more expensive than diesel (€1.24/km). A probabilistic analysis based on 10,000 Latin Hypercube simulations and six uncertain parameters shows that Make is less costly in 78.8% of cases and Buy in 21.2%. The median probabilistic break-even price is €10.38/kg, with a 5th–95th percentile range of €8.79–12.38/kg. Delivered hydrogen price is the main driver, followed by Make CAPEX, fleet utilization, and financing conditions. Hydrogen sourcing therefore remains a strategic investment choice, with implications for capital exposure, renewable-energy integration, economic sustainability, and supply resilience. Full article

Mobility-as-a-Service (MaaS) has emerged as a promising approach to urban transportation by integrating multiple mobility services into a single digital platform for trip planning, booking, and payment. More recently, Artificial Intelligence (AI) has expanded the capabilities of MaaS, enabling more efficient data processing, predictive analytics, personalized services, and intelligent decision support. This narrative review examines the current state of research on AI-enabled MaaS from both technological and socioeconomic perspectives. The analysis covers five major research areas: data integration and interoperability, predictive systems and demand forecasting, AI-enabled decision support for policy and planning, fairness and ethical AI, and cybersecurity and privacy protection. The findings show that successful implementation depends not only on advances in AI algorithms but also on high-quality interoperable data, effective governance, regulatory support, public trust, and collaboration among stakeholders. The review concludes that the main challenges facing AI-enabled MaaS are no longer primarily technical but organizational, institutional, and social. Future research should focus on trustworthy and explainable AI, privacy-preserving learning, standardized evaluation methods, fairness-aware optimization, resilient cybersecurity, and long-term assessments of MaaS impacts on sustainable urban mobility. Full article

Heavy metal contamination of agricultural soils and urban green spaces has become a major environmental concern, threatening ecosystem functioning, food safety, and sustainable land management. Silicon-based growing media have emerged as an environmentally friendly approach for reducing metal mobility while enhancing plant establishment in contaminated environments. Despite growing research interest, a comprehensive evaluation of the mechanisms, effectiveness, and practical applications of silicon-amended growing media across diverse plant systems remains lacking. This systematic review addresses this gap by synthesizing current evidence following the PRISMA 2020 framework. A systematic search of Web of Science, Scopus, PubMed, ResearchGate and Google Scholar identified 247 publications published between 2010 and 2025, of which 32 peer-reviewed studies met the predefined inclusion criteria for qualitative analysis. The reviewed literature demonstrates that silicon incorporation into growing media improves substrate functionality by modifying physicochemical properties, immobilizing heavy metals, regulating metal transport within plants, strengthening antioxidant and osmo-protective defense systems, preserving photosynthetic activity, and improving nutrient acquisition and water-use efficiency. Furthermore, silicon influences molecular signaling pathways and promotes beneficial rhizosphere interactions that collectively enhance plant resilience under metal stress. Among the evaluated materials, silicon nanoparticles consistently exhibited greater remediation efficiency than conventional silicon sources because of their higher surface reactivity and improved bioavailability. Overall, silicon-based substrate engineering represents a multifunctional and sustainable strategy for mitigating heavy metal contamination while improving the performance of agricultural crops and urban vegetation. Future research should focus on validating these findings under long-term field conditions, optimizing silicon formulations for different substrate types and contamination scenarios, evaluating environmental safety, and integrating silicon-based technologies into climate-resilient agricultural practices and urban green infrastructure. Full article

Advanced Air Mobility (AAM) is increasingly recognized as a promising approach for improving healthcare logistics, yet evidence remains fragmented across aviation, transportation, healthcare, and digital infrastructure. This study examined the operational, clinical, and institutional evidence to characterize the evolution of healthcare-focused AAM, identify dominant research themes, and determine critical knowledge gaps. The review followed PRISMA-ScR guidelines and combined bibliometric analysis, thematic synthesis, and semantic network analysis of 168 peer-reviewed studies published between 2015 and 2025 and retrieved from IEEE Xplore, ScienceDirect, Scopus, and Web of Science. The analysis identified six thematic clusters encompassing system design, healthcare logistics, biological specimen transport, emergency response, health equity, and digital infrastructure. Publication activity increased rapidly after 2020. Emergency response represented the most mature research domain, and pharmaceutical logistics, longitudinal operational validation, and health equity remained comparatively underdeveloped. These findings demonstrate that healthcare-focused AAM functions as a sociotechnical system requiring coordinated advances in technology, governance, institutional integration, and equitable access to support clinically reliable and operationally sustainable healthcare delivery. Full article

Scientific Problem: Governments worldwide are deploying AI-enabled services at scale, yet uncertainty persists about whether these systems genuinely contribute to citizen satisfaction and institutional trust and what organisational conditions make them do so. Existing research has examined technical AI capability and organisational data culture in isolation, leaving unresolved whether both exert independent effects when modelled together and whether emotional and relational mechanisms explain how these antecedents reach citizen outcomes. Aim: This study tests whether AI Sophistication (AIS) and Big Data Organisational Culture (BDOC) independently influence Customer Experience (CX) and Public Trust (PT) in UAE government AI services, whether Emotional Intelligence (EI) and the Real-Time Commensality (RTC) scale developed in this study mediate those relationships, and whether Multicultural Competence (MC) moderates them. Method: Survey data were collected between October and December 2024 from N = 500 verified users of UAE government AI services across healthcare, education, transportation, and administrative domains. All seven constructs were validated against standard psychometric thresholds (AVE > 0.70, CR > 0.88, HTMT < 0.85). A Dual-Driver Mediation–Moderation Model was tested using hierarchical regression, bootstrapped mediation (Hayes PROCESS macro, 5000 resamples), and interaction-term moderation. Results: AIS and BDOC showed near-identical associations with CX (B = 0.567 and B = 0.568, p < 0.001), consistent with dual-driver equivalence. In the full model, BDOC substantially outperformed AIS as a predictor of PT (B = 0.294 vs. B = 0.108). All eight mediation pathways were supported, with EI showing consistently larger indirect effects (range: 0.070–0.093) than RTC (range: 0.049–0.072). EI recorded the lowest construct mean (M = 1.959) despite being the strongest mediator—the affective gap. MC did not moderate any pathway, indicating no model-level evidence of differential associations across levels of Multicultural Competence; given the configural-only invariance assessment, this should not be interpreted as conclusive proof of cultural convergence. Conclusions: These findings extend the DeLone and McLean IS Success Model by positioning BDOC as a co-equal predictor of citizen satisfaction and the stronger predictor of institutional trust—suggesting that sustainable government AI delivery may depend as much on organisational culture as on technical capability. Future Research: Longitudinal designs, cross-country comparisons, and validation of RTC against established social presence measures are identified as priority future directions. Full article

As a potential contributor to urban sustainability, the commercialization of Urban Air Mobility depends on social license rather than mere technical feasibility. To address the limitations of the Technology Acceptance Model (TAM) in high-risk contexts, this study integrates trust, perceived risk, personal innovativeness, and governance expectation to construct an extended acceptance model tailored to China’s policy-driven institutional environment. Based on 567 valid samples analyzed via Structural Equation Modeling (SEM) and Multi-Group Analysis (MGA), the results reveal three core mechanisms. First, perceived risk positively enhances perceived usefulness (β = 0.765, p < 0.001) via risk-induced cognitive reframing, indicating that the public rationalizes threats by amplifying the technology’s functional value. Second, trust exhibits a strong compensatory effect on perceived ease of use (β = 0.885, p < 0.001) and directly drives behavioral intention (β = 0.549, p < 0.001), serving as a heuristic to reduce perceived complexity in risky decisions. Third, governance expectation directly drives behavioral intention (β = 0.225, p = 0.004) and attitude (β = 0.201, p = 0.007), confirming the primacy of institutional trust in China. The model explains 50.5% of the variance in behavioral intention (R² = 0.505) and 48.6% in attitude (R² = 0.486). Notably, the direct effects of perceived ease of use on intention were non-significant, redefining TAM boundaries where safety supersedes efficiency. Finally, gender moderates the covariance between innovativeness and governance expectation (female β = 0.765 vs. male β = 0.720, C.R. = 3.196, p = 0.001), revealing higher institutional dependency among females. These findings elucidate the risk–trust institution nexus in UAM, offering empirical evidence for differentiated sustainable transport policies and marketing strategies. Full article

Circulating fluidized bed (CFB) boilers combine multiphase dynamics, long transport delays, and multimode operation that challenge condition monitoring and performance evaluation. This structured narrative review surveys artificial intelligence for CFB state monitoring, fault diagnosis, performance assessment, and combustion optimization (2005–2026), supported by a reproducible literature search, structured evidence workbook, and concise quality appraisal. The literature is organized by monitoring objectives and method families from soft sensors and deep learning to physics-informed hybrids, digital twins, and multimodal non-destructive testing. Most included evidence remains single-unit and retrospective or offline; accuracy gains in publications often outpace verified sustained online use. One 150 MW project report estimated approximately EUR 699,000 in annualized benefits (not independently audited). Remaining gaps include cross-unit generalization, standardized benchmarks, secure deployment, and closed-loop diagnostics–maintenance integration. Full article

Unmanned aerial vehicles (UAVs) are increasingly considered as enabling technologies for last-mile delivery, emergency medical response, and smart-city applications. However, drone-based logistics, emergency communication, sensing activities, and future aerial mobility are often addressed as separate research domains. This article proposes a four-dimensional planning framework for drone-enabled mobility, integrating goods, information, sensing, and human mobility within a unified conceptual structure. The framework is developed through a literature-informed conceptual analysis and previous applied research experiences related to drone-assisted logistics and emergency communication. Goods mobility includes parcel delivery, medical logistics, emergency supply transport, and hybrid operational models involving trucks, public transport, depots, and micro-hubs. Information mobility refers to the use of drones as mobile communication tools for emergency warnings, citizen interaction, drone-to-infrastructure communication, and infomobility services. Sensing mobility concerns traffic monitoring, environmental observation, disaster mapping, crowd monitoring, and infrastructure inspection. Human mobility is considered as an emerging extension related to urban air mobility (UAM), electric vertical take-off and landing (eVTOL) systems, and low-altitude aerial corridors. Cross-cutting issues such as energy autonomy, solar-assisted drones, multimodal integration, safety, communication, regulation, sustainability, and public acceptance are discussed. The proposed framework provides a structured basis for assessing drones as components of sustainable, resilient, and multimodal mobility systems. Full article

Sustainable public transport in South Africa has become a policy priority over the past few decades. Safety is recognised as a fundamental component of this agenda. In many cities, public transport systems are often characterised by poor safety standards, which undermine ridership and public confidence. In the City of Polokwane, despite the successful recent completion of the first phase of Leeto La Polokwane bus system, an Intelligent Transportation System designed for sustainable transport management, the safety performance of the system and its subsequent influence on travel behaviour remain underexplored. This study addresses this gap by investigating the safety performance of the Leeto La Polokwane Phase 1A and its relationship with commuters’ sustainable travel mode choice. Commuter surveys (n = 344), field observations, and actual ridership data were used to collect data. Principal component analysis extracted two key factors (commuter safety and crime prevention), which together explained 63.14% of the total variance in commuters’ perceptions of safety. Commuters reported a neutral perception of commuter safety (mean = 4.03) and a negative perception of crime prevention (mean = 3.90). Multinomial logistic regression revealed that commuters’ perceptions of safety, particularly concerns related to crime prevention, were statistically significant predictors of sustainable travel mode choice. Multiple linear regression further showed that operational continuity and system maturation were positively associated with ridership growth, with operating days (β = 0.307, p = 0.044) and time in operation (β = 0.670, p < 0.001) emerging as significant predictors. Although taxi protests (β = −0.036, p = 0.804) and school holidays (β = −0.199, p = 0.181) were negatively correlated with ridership. The study concludes that safety is a critical determinant of sustainable public transport use that extends beyond the onboard environment to include the entire commuter journey. To improve public transport safety requires a holistic strategy that integrates safe pedestrian infrastructure, effective crime prevention, operational reliability, and strengthened institutional collaboration. Full article