Search Results (1,697)

Long-term decarbonization of urban residential buildings in southern China depends on the joint evolution of building stock, end-use efficiency, and electricity carbon intensity. This study develops a dynamic stock-energy-carbon framework for urban residential buildings in China’s hot-summer warm-winter region from 2010 to 2060, using Guangdong, Guangxi, Fujian, and Hainan as case provinces. The model links demographic and housing-space change with stock survival, retrofit of the base-year stock, cohort-specific performance levels for post-2022 new construction, and time-varying provincial grid emission factors. EnergyPlus simulations of seven high-rise residential archetypes show that nearly zero-energy performance reduces province-level EUI by 19.2–26.5% relative to the baseline, with cooling-load reductions forming the dominant part of the improvement in the warmer provinces. Across coupled demand-side scenarios, stricter new-build performance standards reduce 2026–2060 cumulative operational energy by 5.3–10.1% relative to the conservative demand-side setting, while increasing retrofit intensity provides a smaller but consistent additional reduction. Carbon outcomes are more sensitive to electricity-sector assumptions: under the main demand-side setting, moving from the conservative to the accelerated grid pathway advances the operational-carbon peak by 8–15 years across the four provinces and lowers 2060 residual emissions by about 71%. A comparison with available observed provincial household-electricity statistics is added as a plausibility check; it confirms the relevant order of magnitude but also indicates that absolute demand estimates should be interpreted cautiously because of boundary and EUI-representation differences. These results suggest that demand-side efficiency policies must be coordinated with rapid provincial power-sector decarbonization if the residential sector in Hot-Summer Warm-Winter Region is to reach earlier carbon peaks and lower residual operational emissions. Full article

This paper presents a deployment-oriented longitudinal platoon-control architecture for connected and autonomous vehicles operating under repeated leader hard-braking, cut-ins, and spatially varying road friction. The proposed stack combines four elements: (i) a lightweight scalar Kalman filter (KF) that smooths a friction-related signal and feeds friction-dependent constraint tightening; (ii) a model predictive control (MPC) backbone whose weights and horizon are selected offline using multi-objective GA/NSGA-II tuning; (iii) a bounded proximal policy optimization (PPO) residual policy, trained with the aid of a learned surrogate model, that refines the MPC command during transient events; and (iv) a command-level safety projection that enforces instantaneous actuation and clearance constraints at the fast control tick. The contribution is therefore not a new MPC formulation or a new reinforcement-learning algorithm in isolation, but an integrated and experimentally characterized control stack that keeps the safety-critical structure explicit while using learning to improve transient behavior. The method is evaluated in a CARLA digital twin of a six-vehicle platoon over a 5 km mixed urban–highway route and is further assessed in hardware-in-the-loop (HIL) on an automotive ECU using a multi-rate ROS 2/AUTOSAR implementation (50 Hz estimation/safety loop, 10 Hz MPC/RL refresh). Across 10 held-out disturbance seeds, the full stack improves spacing regulation, maintains non-amplifying disturbance propagation according to the reported string-stability indices, and reduces a route-normalized positive tractive-energy-at-the-wheels proxy by about 12% relative to Manual MPC and by up to 18% relative to a PID-CACC reference. Because the PID-CACC baseline does not enforce hard constraints and can collide under the tested disturbance suite, the main performance comparison is among collision-free controllers. The friction signal used in CARLA is derived from simulator road-surface annotations before filtering, so the present study should be interpreted as a friction-aware control and integration study rather than a validated onboard friction-estimation result. Likewise, the reported energy metric is an effort proxy and is not a calibrated fuel or battery consumption model. Full article

As a novel urban leisure activity, Citywalk is reshaping the spatial organization of urban tourism resources and spatial experience patterns. This phenomenon provides a crucial entry point for understanding new tourist–destination relationships from the perspective of spatial behavior. This paper takes Harbin, an Internet-Famous City (IFC), as a case study and integrates multi-source data, including pedestrian trajectories, social media texts, and urban infrastructure. A cross-modal analytical framework for Citywalk networks is constructed to examine the structural evolution of Citywalk networks and the relationship between digital-space and physical-space in the context of IFCs. The results indicate that: (1) During its rise as an IFC, Harbin’s Citywalk network transformed from a single-core agglomeration structure to a multi-nodal radial structure, exhibiting a pattern of core reinforcement and outward expansion. (2) Online visibility was associated with the emergence of new nodes and network expansion, but a structural misalignment was observed between digital-space association and physical-space linkage. (3) Emotional differentiation among newly visible nodes further reflected the uneven development of the Citywalk network, while concentrated digital attention was accompanied by persistent structural imbalance. This study highlights the digital–physical misalignment in urban tourism networks, suggests the important role of social media in shaping tourists’ route imagination and emotional evaluation, and provides references for the spatial optimization and sustainable management of urban tourism resources in the new development stage. Full article

Existing research on the landscape patterns of urban parks and green spaces demonstrates a disproportionate focus across tiers within China’s urban hierarchy. Numerous studies have concentrated on economically developed first-tier cities, such as Beijing, Shanghai, and Guangzhou. In contrast, medium-to-large non-first-tier cities, especially provincial capitals and emerging cities within the first- and second tiers, have been relatively understudied, although they have received increasing attention in recent years. This bias extends regionally, with studies predominantly examining cities in the more developed central and eastern regions, while less-developed areas and lower-tier cities receive significantly less attention. This study tracks changes in park quantity, spatial concentration, patch structure and driver associations at three planning-related time points. Shenyang provides a distinct cold-region and old industrial city case, shaped by long winters, industrial renewal and outward urban growth. Furthermore, to inform park and green-space planning in Northeast China’s cold-climate cities, exemplified here by Shenyang, a major metropolis with a monsoon-influenced humid continental climate (Köppen Dwa), long cold winters, and relatively short warm summers, we document a shift in park distribution from the urban core to peripheral areas. Based on park vector layers reconstructed from planning documents, remote sensing interpretation and field verification, this study combined spatial analysis, landscape metric calculation and driver-association modeling. ArcGIS Pro was used to identify changes in distribution centers, directional extension and local clustering; FRAGSTATS 4.2 was used to calculate park landscape metrics; and SIMCA-P 14.1 was used to examine the statistical associations between selected landscape indicators and potential driving variables. The results show that the number and total area of parks in central Shenyang increased substantially from 2000 to 2024. Spatially, park distribution became less concentrated in the traditional inner city, while new clusters gradually appeared in peripheral districts and newly developed urban areas. The old urban core remained important, but its dominance weakened as park provision expanded outward. The landscape metric results further indicate that park expansion was accompanied by more irregular patch forms, stronger fragmentation and declining structural continuity. The driver association analysis suggests that climate conditions, population change, industrial restructuring, real estate investment, road construction and urban greening policies were related to different aspects of park landscape change. These associations should be interpreted as statistical relationships rather than direct causal effects. Overall, this study clarifies the spatial restructuring of park green spaces in a cold-region old industrial city and provides planning evidence for improving park connectivity, coordinating green space expansion with urban construction and supporting sustainable park system development in Northeast China. Full article

With the large-scale integration of new energy, electric vehicles, and other new loads, disorderly electricity consumption has led to surging peak loads and heightened overload risks for distribution transformers. Particularly in aging, high-density urban areas constrained by the cost and space limitations of upgrading distribution facilities, there is an urgent need to tap into the flexible load control potential of existing power distribution systems to ensure system safety. This paper proposes a multi-timescale cooperative scheduling framework for flexible loads in distribution systems, deeply integrating the dynamic load capacity of transformers with the dispatchable characteristics of a flexible load. First, a day-ahead scheduling layer based on multi-agent reinforcement learning is constructed to optimize electricity plans and smooth peak–valley loads in the distribution system. Second, a dynamic transformer-rating model for distribution transformers is established to uncover their dynamic load capabilities under varying environmental conditions. Finally, an intraday scheduling layer for flexible loads is developed. It dynamically matches the regulation demands of distribution transformers and flexible loads via real-time optimization of consumption strategies to address electricity price fluctuations and user behavior randomness. Case study results demonstrate that the methods described in this paper effectively reduce power load fluctuations, ensuring the safe and stable operation of distribution and power supply systems. Full article

This paper draws on primary research conducted within the international project New Governance for New Spaces—NONA, implemented under the Interreg Danube Region Programme with EU co-funding. The principles of the New European Bauhaus (NEB) initiative are fully aligned with the research framework and outcomes. The study aimed to test the applicability of the NEB model in urban regeneration at four selected pilot sites in four mid-sized cities in Eastern Europe (Bulgaria, Hungary, Bosnia and Herzegovina, and Serbia) with a strong focus on participatory governance and co-creation involving stakeholders, local authorities, and citizens. It also examined appropriate financing and management models to support sustainable improvement and future development of these spaces. A central outcome of the research was the development of a comprehensive methodological framework outlining key steps and potential implementation scenarios, designed as a roadmap for medium-sized European cities. The methodology combined field research, surveys, the establishment of a Local Action Group (LAG), and the implementation of “soft interventions,” including creative competitions, site-based festivals, workshops, expert walks, and panel discussions and forums. These activities informed a set of beneficial practice recommendations, defined through clear requirements and expected outcomes. Full article

Addressing global urbanization and demographic shifts, this study argues that urban affordance—the environment’s capacity to promote or constrain healthy activities—is the critical link missing in current ageing in place (AIP) models. The research introduces a new multidisciplinary approach bridging urbanism, statistics, and psychology to evaluate the relationship between urban space and ageing through the lens of environmental affordance. It synthesizes 47 indicators across five macro-areas (demographic, economic, healthcare, social–relational and urban–environmental) into a composite index named the index of Vulnerability for Ageing in place and Longevity (VAL index). It maps over 65 vulnerabilities related to AIP at the neighbourhood level in Bergamo, an Italian medium-sized city. The VAL index reveals critical discrepancies between objective urban determinants and subjective resident conditions (e.g., high walkability contrast with low perceived safety). In conclusion, this index reorients urban planning for ageing, leveraging an AIP approach to advance spatial justice and demographic resilience. Full article

Abandoned mine methane (AMM) emissions represent a significant public safety and environmental hazard in post-industrial urban areas. Uncontrolled subsurface gas migration may lead to explosive accumulations in confined spaces, human exposure, infrastructure damage, and additional greenhouse gas emissions. This study develops an integrated risk assessment framework for AMM in urban environments, combining quantitative analysis of field monitoring data with semi-quantitative probability–consequence risk matrices and multi-factor evaluation. Methane concentrations were measured at 41 monitoring points during three campaigns (August–September 2024). A total of 42 influencing factors were identified and classified into seven categories (geological, mining, hydrogeological, meteorological, anthropogenic, biological, and special phenomena). Exceedance probabilities of critical thresholds were estimated with 95% confidence intervals. Consequence weights were derived using the Analytic Hierarchy Process (AHP) based on a five-expert panel (CR = 0.043). The framework was applied to the urban area of Lupeni, Romania, where methane concentrations of up to 54% vol. were measured during borehole screening measurements (subsurface probe points). Elevated concentrations were detected four days after commissioning of a new gas pipeline. Gas chromatographic analysis excluded pipeline leakage and confirmed a mining-related source. Results indicate a localized critical risk (R = 25 on a 1–25 scale) in hotspot P2, with a 95% confidence interval for the probability of exceeding the 3% vol. alert threshold of [0.885–1.00], justifying immediate mitigation through controlled drainage. Post-intervention monitoring showed a reduction to instrumentally undetectable levels by February 2025. The study demonstrates that administrative mine closure does not eliminate residual methane risk and proposes a complete decision-support algorithm (URBAN-MINE-RISK) for similar urban settings. The applicability of structural reliability methods (e.g., FORM) is discussed as a future research direction. The methodology is transferable to other post-mining regions in Central and Eastern Europe. Full article

Autonomous flight of UAVs in unmapped environments remains a hot topic in research. While vision- and LiDAR-based autonomy has advanced rapidly for multirotor platforms, research on low-altitude autonomous flight for fixed-wing UAVs is still limited. To address obstacle avoidance in unmapped and complex 3D environments for fixed-wing UAVs, this paper proposes a neural network named FW-MonoAvoid-Net. This network is an end-to-end monocular-vision-based framework for fixed-wing UAVs to accomplish environment awareness and obstacle avoidance. Firstly, we develop a simulation framework to collect safe flight-trajectory data across diverse flight conditions, which is employed to train the proposed FW-MonoAvoid-Net. The proposed flight-learning framework adopts a lightweight visual perception network and a kinematics-aware state fusion module to predict the trajectory. At the output stage, an explicit physics-constrained decoder is embedded to strictly confine predicted trajectories within the feasible flight envelope of fixed-wing UAVs. Experiments are conducted in aerial (simulated spherical obstacles), canyon, urban (simulated high buildings), and New York Manhattan city scenarios. In the Manhattan city test, it achieves an 82.26% success rate at approximately 105 m flight altitude and 20 m/s cruise speed. Manhattan city is not included in the training datasets, FW-MonoAvoid-Net did not “see” similar scenarios in the training process. The testing results demonstrate its strong generalization and zero-shot deployment capability across unmapped environments within the simulation setting. FW-MonoAvoid-Net is a “smaller” model which has fewer than 3 million parameters. A Jetson Orin NX 16GB platform was employed to test the computation efficiency, and the trajectory-generation module reaches an average inference latency of 5.21 ms (about 190 Hz). These results show that, under limited computation and power consumption, the proposed method maintains both high success rates and excellent real-time performance. FW-MonoAvoid-Net is expected to help develop a fully autonomous fixed-wing flight in unmapped 3D spaces. Full article

Since the 1980s, South Korea has continuously supplied public rental housing alongside the development of new towns. However, systematic studies examining the relationship between qualitative changes in floor plan design and the institutional factors influencing them remain limited. This study is based on the premise that floor plans in public rental housing are not merely the result of design improvements, but are structurally shaped by legal and institutional frameworks. It systematically analyzes changes in floor plan types and planning elements according to development periods and housing sizes. To achieve this, this study examines public rental housing supplied in Korean new towns from the 1990s to the 2010s, classifying floor plan types by period and housing size and analyzing their planning characteristics. The analysis focuses on the composition and arrangement of interior spaces, the size of each space, bay structure, and aspect ratio. A comparative analysis further examines the relationship between floor plan changes and relevant laws and institutional frameworks. The results show that floor plan configurations evolved in distinct phases in response to institutional changes and housing size differentiation. In the 1990s, standardized one-bay layouts with integrated living and sleeping spaces were predominant under strict regulatory conditions, including spatial dimension constraints. In the 2000s, following the legalization of balcony extensions, floor plans diversified into two-bay and three-bay configurations. In the 2010s, floor plan types became increasingly diversified and complex under the influence of district unit plans and detailed design guidelines issued by public agencies. In terms of housing size, smaller units (around 20 m²) maintained simplified one-room configurations, while medium-sized units (around 30–40 m²) exhibited a clear transition from integrated to functionally separated layouts, and larger units (around 50 m²) showed a significant increase in spatial diversity and variation in layout composition. These findings indicate that floor plan evolution is not a linear process of design improvement, but a structurally conditioned transformation shaped by regulatory frameworks, institutional changes, and path dependency. The persistence and gradual modification of earlier standardized layouts suggest that floor plan configurations are continuously reproduced and adapted within institutional constraints. By empirically identifying the structural relationship between institutional frameworks and floor plan design, this study reveals the mechanisms through which institutional conditions shape housing design. Furthermore, it contributes to an interdisciplinary understanding that integrates architecture, urban planning, and housing policy, and provides important implications for design guidelines and policy development aimed at improving the quality of public rental housing. Full article

In urban environments characterized by narrow roads and dense networks with short intersection spacing and high connectivity, traffic flows exhibit strong spatiotemporal coupling and pose safety challenges. Conventional traffic signal control approaches are difficult to achieve effective regional coordination, while existing control models based on artificial intelligence (AI) lack consideration for trustworthiness and robustness. To address these challenges, an AI-driven traffic control method for digital city traffic signals is proposed. A unified and decodable latent action representation space is constructed, in which the dependency between phase selection and green time duration is captured using discrete action embedding tables and a conditional variational autoencoder (CVAE), ensuring the stability and interpretability of the AI-driven model. Building on this foundation, a globally shared latent representation is integrated with a local coordination mechanism, and the proximal policy optimization (PPO) algorithm is employed for policy training. A state residual prediction regularization loss is introduced to improve the model’s generalization capability and convergence efficiency. Experiments were conducted using a real-road network and traffic flow data from the Rongdong District of Xiongan New Area. Under spatially imbalanced peak hour traffic conditions, the model reduced average vehicle delay by 14.84% and average queue length by 9.2%; under temporally imbalanced peak hour traffic, it achieved reductions of 5.36% and 7.2% in delay and queue length, respectively. These results demonstrate that the proposed method significantly enhances both traffic efficiency and system robustness, offering scalable, reliable technical support for secure and intelligent transportation systems (ITSs). Full article

In people-centered urban planning, enhancing the well-being of residents and tourists is one of the core objectives. Tourist emotion serves not only as a key indicator of the tourism experience but also indirectly reflects the quality of a city’s public spaces and built environment. In recent years, user-generated content has provided abundant data for understanding human emotional responses in urban environments, while deep learning models offer new technological pathways for extracting spatial–emotional associations from such data. However, existing research lacks a systematic evaluation of emotion analysis models from an urban spatial perspective and their application to uncover the relationship between emotional distribution and spatial characteristics in specific urban contexts. Based on a dataset of 9419 manually annotated travel reviews from Harbin, this study developed a multi-level evaluation framework and conducted a systematic comparison of seven emotion analysis models. This study then screened for the optimal model combinations based on two dimensions—spatial location and emotion polarity—to create a model matching matrix for mapping Harbin’s emotion map. Subsequently, a regression analysis was performed to examine the relationship between emotions and built environment elements. The results show that the ERNIE model demonstrated the best overall performance. Road density, green space density, and accommodation facility density were positively correlated with emotion, while POI diversity showed a negative correlation. This study demonstrates that emotion analysis technology can serve as a valuable analytical tool for identifying spatial patterns of sentiment, thereby offering empirical support for optimizing spatial design parameters and advancing a more people-centered approach to urban development. Full article

In the context of climate change and the challenge of strengthening urban biodiversity, this paper examines the potential of speculative drawing as a methodological tool for developing biodiversity scenarios of the cityscape within the framework of the New European Bauhaus initiative. The research is based on the initiative’s core values of beautiful, sustainable, and together, and is conducted using a drawing-based methodology grounded in inductive reasoning across three spatial scales in Block 30, which is part of the spatial cultural-historical unit of the Central Zone of New Belgrade. The potentials for biodiversity development are explored at the scale of the apartment, the facade, and the open space of the block. By examining the interactions between the indoor and open spaces of mass housing, ecological potentials emerge. The experimental process demonstrates that drawing can function as a methodological tool that reveals opportunities for community engagement through drawing practices. The proposed layering of drawings offers interpretations of cityscape transformation at each of the three scales. Through speculative scenarios, the drawings provide a methodological tool to co-create biodiversity interventions in mass housing as a sensitive architectural layer within the design process, fostering a new understanding of the relationship between nature and the cityscape. Full article

Under growing urbanization and environmental challenges, sustainable urban mobility has become a critical priority for cities worldwide. Public Transport (PT) systems play a central role in reducing car dependency, lowering emissions, increasing network capacity, and promoting more equitable and efficient access to urban spaces for all users. Hence, the present paper aims to investigate PT preferences in the city of Larissa, Greece. Larissa is a medium-sized city currently serviced only by buses, and is currently focusing on the potential introduction of a new tram system to operate in parallel with existing bus services. To this end, a SP survey was designed and implemented, resulting in 972 observations that were collected for further statistical analysis. Survey results show a slight preference for trams over buses, with 54.63% selecting the tram and 45.37% favoring the buses. Moreover, a context-based segmentation pipeline was established using PCA, DBSCAN and t-SNE algorithms, aiding the visualization of existing clusters for transport choice approaches. Afterwards, a series of mixed logit models was applied, and statistically significant variables influencing mode choice were determined. The study also examines Value of Time (VoT) metrics and finds that respondents assign lower VoTs to trams than to buses, especially in out-of-vehicle segments of the journey, such as waiting and walking, and therefore consider trams as more pleasant and less burdensome. The findings also indicate that passengers place a high value on the quality of infrastructure related to access and waiting times, underlining the need to improve the overall user experience beyond the vehicle itself. In summary, the present research offers valuable insights into how the introduction of a tram system could possibly reshape PT usage patterns when compared with the legacy existing bus services. Full article

The people-oriented city serves as the value orientation of urban work in the new era, and age-friendliness is precisely its core practical standard for intergenerational equity and inclusive sharing. Currently, the renovation of old residential areas should transcend single-dimensional physical patching and shift towards an all-age-friendly model that meets the complex needs of multi-age groups. Taking Tuanjiehu Communities in Beijing as a case study, this research constructs an evaluation system covering three dimensions—place, atmosphere, and culture—and 22 third-level indicators, and adopts the Semantic Differential Method (SD) and Analytic Hierarchy Process (AHP) to quantitatively analyze residents’ perceptions. The study finds that old residential areas generally suffer from problems such as “insufficient place safety and functionality, lack of atmospheric vitality, and weak cultural cultivation”. Based on these findings, a progressive renewal strategy of “Consolidating Safety Foundation → Boosting Community Vitality → Cultivating Community Culture” is proposed, offering an empirical illustration for the all-age-friendly renovation of high-density urban old residential areas to transform from “survival-oriented” spaces to “life-oriented” homes, offering preliminary insights for the all-age-friendly renovation of similar high-density urban old residential areas. Full article