Search Results (179)

While urban historic areas are most vulnerable to disasters, they offer insights into leveraging their features to mitigate risk. This study analyzes scientific approaches to evacuation simulations to assess the tolerance of historic areas. Using a heritage-led disaster risk reduction approach, this study uses a heritage site as a case study for evacuation. This study uses a GIS-based methodology to define various blockage risks, categorizing them as no-obstruction, rubble-obstruction, on-street vehicle obstruction, and combined obstruction. The input parameters were transferred from a GIS to a simulation application, with combined obstruction representing the worst-case scenario. No-obstruction served as a baseline for measuring historic area vulnerability. Statistical analysis evaluated time usage and the number of evacuees, while GIS identified vulnerable places and street congestion. Obstructions significantly increase evacuation risks, with combined obstructions posing a 3.8 times higher risk than the no obstruction scenario (2638 s compared to 683 s). Vehicle obstruction causes a vulnerability of 1404 s, while building collapse-related rubble obstruction causes a vulnerability of 1073.1 s, despite creating dead-end streets. The strategy of reinventing heritage sites as temporary evacuation sites appears viable. This approach can support evacuees during and after disaster responses and expand options for ensuring urban heritage resilience. Full article

The kindergarten activity unit is the main space for children’s daily life and learning, and also represents a special type of densely populated public building. Its layout and evacuation design play an important role in ensuring children’s safety and improving evacuation efficiency in emergency situations. Therefore, our study aims to achieve a paradigm shift in kindergarten evacuation research, from the discrete analysis of evacuation ‘components’ (such as corridors and entrances) to integrated analysis of the ‘activity units’ as a whole system. As a complete evacuation analysis unit, the focus is on exploring the coupling mechanism between its internal spatial configuration and functional block layout, in order to improve evacuation efficiency. The results showed that when the classroom and dormitory of the activity unit are compared, the reasonable location for the exit of the classroom and dormitory can shorten the average evacuation time by 13.84%. When classrooms and dormitories are separated, it is necessary to control the connection exits between the classrooms and dormitories as well as the independent exits of the classrooms. This can significantly reduce the average evacuation time. The results of this study will help improve the survival ability of children in emergency situations, ensuring their safety and well-being. Full article

Subway stations are enclosed spaces with high passenger density and complex evacuation conditions. Fires in such environments can escalate rapidly and cause severe consequences. This study proposes a dynamic risk assessment model grounded in dual symmetries. The first symmetry is a balanced “Human–Machine–Environment–Management” analytical structure. The second is a coherent model transformation from a Fault Tree (FT) to a Bayesian Network (BN). Shuanggang Station on Nanchang Metro Line 1 serves as a case study. This work establishes a comprehensive evaluation system based on 4 first-level indicators of man–machine–environment–management, 9 secondary indicators, and 27 tertiary indicators. FT analysis identified 117 minimal cuts and 14 minimal paths, pinpointing core risk nodes such as flammable materials and oxidizers, electrical equipment overheating, and fire management deficiencies. The model was then symmetrically converted into a BN using GeNle Academic 4.1 software to support dynamic probability inference. The results show that prevention measures at Shuanggang Station reduce the fire occurrence probability from 0.000249 to 0.00007 (a 71.9% reduction). The probability importance of rescue escape routes is 0.00223. This indicates that the accessibility of rescue routes constitutes a highly sensitive hazard. The symmetric framework and modeling approach offer a scientific basis for targeted fire prevention, control, and evacuation management in the Nanchang Metro and similar stations. The findings support improvements in the safety and resilience of metro operations. Full article

The growing incidence of natural and man-made disasters, exacerbated by climate change, has highlighted the role of urban planning and design in reducing the impact of the risks they pose. This refers to pre-disaster recovery planning (PDRP), an innovative practice that aims to improve the response of urban contexts affected by a disaster, with urban planning actions implemented in peacetime, i.e., before the disaster occurs. This paper presents a methodology that integrates agent-based simulation and safety-based urban design within a sustainability-oriented urban planning framework. The methodology aims to support the design of safer and more resilient public spaces, focusing on open areas within heritage districts and operating within a sustainability-oriented urban planning framework. The proposed approach integrates simulation and design to evaluate the performance of existing spatial layouts under stress conditions and explore alternative configurations that optimize evacuation dynamics and minimize risks. The result of applying the simulation to the current urban context therefore allows for the identification of appropriate urban design techniques and practices aimed at defining alternative spatial scenarios and improving the urban form in terms of its evacuation performance. Full article

Urban underground spaces, including tunnels, subways, and underground commercial buildings, have grown quickly as urbanization has progressed. Fires frequently break out following industrial accidents and multi-hazard natural disasters, and they can severely damage human health. Fire smoke is a major contributor and a major hazard to public safety. The flow patterns of fire smoke in underground spaces, the risks to human casualties, and engineering and personal protective technologies are all thoroughly reviewed in this work. First, it analyzes the diffusion characteristics of fire smoke in underground spaces and summarizes the coupling effects between human behavior and smoke spread. Then, it examines the risks of casualties caused by toxic gases, particulate matter, and thermal effects in fire smoke from both macroscopic case studies and microscopic toxicological viewpoints. It summarizes engineering protection strategies, such as optimizing ventilation systems, intelligent monitoring and early warning systems, and advances in the application of new materials in personal respiratory protective equipment. Future studies should concentrate on interdisciplinary collaboration, creating more precise models of the interactions between people and fire smoke and putting life-cycle management of underground fires into practice. This review aims to provide theoretical and technical support for improving human safety in urban underground space fires, thereby promoting sustainable urban development. Full article

Urbanization and the growing scarcity of surface land resources have highlighted the strategic importance of underground space as a critical component of sustainable urban infrastructure. This study presents a multi-objective optimization framework for underground infrastructure planning around transit hubs, aligning with the principles of Transit-Oriented Development (TOD). By integrating an agent-based model (ABM) with the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and incorporating the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), the framework forms a unified evaluation and optimization tool that accounts for user behavior while addressing competing objectives, including minimizing evacuation time and functional conflicts, maximizing functional efficiency, and reducing layout deviations. Using Qingdaobei Railway Station in China as a case study, the method yields notable improvements: a 15% reduction in evacuation time, a 16% increase in development benefits, and a more balanced spatial configuration. Beyond technical gains, the study also discusses station planning and governance under the TOD policy context, highlighting how integrated layouts can alleviate congestion, strengthen functional synergy, and support sustainable urban development. Full article

The global shift towards cleaner energy sources is driving the adoption of hydrogen as an environmentally friendly alternative to fossil fuels. Among the forms currently available, Liquid Hydrogen (LH₂) offers high energy density and efficient storage, making it suitable for large-scale transport by rail. However, the flammability of hydrogen poses serious safety concerns, especially when transported through confined spaces such as railway tunnels. In case of an accidental LH₂ release from a freight train, the rapid accumulation and potential ignition of hydrogen could cause catastrophic consequences, especially if freight and passenger trains are present simultaneously in the same tunnel tube. In this study, a three-dimensional computational fluid dynamics model was developed to simulate the dispersion and explosion of LH₂ following an accidental leak from a freight train’s cryo-container in a single-tube double-track railway tunnel, when a passenger train queues behind it on the same track. The overpressure results were analyzed using probit functions to estimate the fatality probabilities for the passenger train’s occupants. The analysis suggests that a significant number of fatalities could be expected among the passengers. However, shorter users’ evacuation times from the passenger train’s wagons and/or longer distances between the two types of trains might reduce the number of potential fatalities. The findings, by providing additional insight into the risks associated with LH₂ transport in railway tunnels, indicate the need for risk mitigation measures and/or traffic management strategies. Full article

China has entered a period of urban renewal, with the focus shifting from large-scale incremental construction to both upgrading existing building quality and adjusting incremental structures. There are three main types of urban renewal: demolition and reconstruction, comprehensive improvement, and organic renewal. The latter systematically optimizes and enhances urban functions, spaces, and culture through gradual renovation methods and is, therefore, suitable for use in ancient cities. To promote organic renewal, the problem of limited space resources must first be addressed, which can be resolved to a certain extent by the moderate development of underground spaces; preliminary evaluations of the development potential are also required. In consideration of the demands of organic renewal, we constructed a novel indicator system for evaluating underground space development potential (USDP) in ancient cities that assesses two dimensions: development demand and development suitability. A multi-factor comprehensive evaluation method was adopted to quantify the indicators of USDP, taking Shaoxing Ancient City (SAC) as the case study. According to the USDP evaluation, SAC can be divided into four kinds of areas: high-potential, general-potential, low-potential, and prohibited development areas. High-potential areas accounted for 16.38% of the total evaluation area and were primarily concentrated in or near key locations: train transit stations (Shaoxing Railway Station), public service facilities, evacuated land, and cultural and tourism facilities around historic districts (Shusheng Guli Historical and Cultural Street). The proposed development strategies for these areas included the interconnection of metro stations, redevelopment of relocation-related and vacated land, construction of underground cultural corridors, and supplementation of parking facilities. For developed underground spaces with low utilization efficiency, functional renewal and management improvement measures were put forward. Our method of evaluating the USDP of ancient cities and the strategies proposed to optimize the utilization of underground space can provide reference examples for SAC and other similar ancient cities. Full article

Social dimensions of environmental conservation are crucial for the long-term success of watershed conservation efforts. This study investigates the intricate relationship between community well-being, socioeconomic factors, and watershed conservation efforts in rural areas, particularly in the Mt. Magdiwata Watershed Forest Reserve (MMWFR) in the Philippines. Using the Structural Equation Model (SEM), the findings highlight that the Quality of Life (QoL, R² = 0.55) is the most influential latent factor shaping local attitudes toward conservation, with the provision of safe evacuation areas and access to green spaces emerging as key priorities. Community willingness (R² = 0.39) to participate in watershed conservation is significantly influenced by socio-economic demographics (R² = 0.31), including civil status, household size, and agricultural dependence, highlighting the need for context-specific conservation strategies. The study also identifies water provisioning (R² = 0.14) as a significant motivator for participation, with accessibility and convenience being more critical than cost in driving community involvement. While the influence of awareness of local environmental policies is relatively low (R² = 0.08), it remains a crucial factor for fostering long-term behavioral change and policy support. The research highlights the importance of integrating socio-economic realities, improving service delivery, and increasing community awareness to develop effective and sustainable watershed conservation programs. Policy frameworks must integrate these relationships in ongoing advocacy for the efficient conservation of MMWFR as a protected area in the Philippine countryside. Full article

Subway stations are complex spaces with high passenger density and mobility, making evacuation efficiency particularly important. The position of evacuation signage is a key factor affecting the efficiency of passenger wayfinding. This study constructed a virtual subway station scenario by virtual reality technology (VR), recording and analyzing the evacuation time and exit selection of 60 participants. The results showed that hanging evacuation signage, with their superior visual advantages, can greatly improve passenger wayfinding efficiency, followed by signage affixed to walls and columns, and finally signage on the ground. This study has provided a theoretical basis for the scientific layout and optimization of evacuation signage positions in subway stations, thereby enhancing passenger safety and evacuation efficiency. Full article

The energy requirements for conditioning spaces have been increasing primarily due to population growth and climate change. This paper shows a comparison between an adsorption (ADC) and absorption cooling (ABC) systems to keep a building below the 25 °C set-point in dynamic conditions, utilizing a latent heat storage tank with MgCl₂·6H₂O and erythritol, and employing evacuated tube and parabolic trough collectors. The storage tank geometry is a plate heat exchanger. An auxiliary system was incorporated to control the temperature range of the solar cooling systems. The results showed that the coefficient of performance was kept around 0.40–0.60 and 0.70 for adsorption and absorption cooling, respectively. The latent heat storage tank with erythritol captured more solar energy than MgCl₂·6H₂O. A maximum solar fraction of 0.96 was obtained with MgCl₂·6H₂O, a thickness of 0.15 m, 20 m² of parabolic trough collector area, and absorption cooling, while the energy supply was fully satisfied with a solar collector with erythritol, a thickness of 0.1 m, 13 m² of parabolic trough area, and absorption cooling. In general, erythritol obtained better results of solar collector fractions than MCHH; however, it has less thermal stability than MgCl₂·6H₂O, and the cost is higher. Full article

Ensuring the safety of building occupants during emergency evacuations is a critical aspect of building design. The spatial configuration and functional layout of buildings significantly influence overall evacuation efficiency. However, accurately assessing evacuation performance based on spatial characteristics remains challenging. This study proposes a weighted network analysis approach to evaluate the evacuation efficiency of buildings. It establishes the “Space-to-Network” diagram translation principles for converting spatial configurations into graph-based representations, defines analytical indicators for evacuation-weighted networks, and introduces a systematic methodology and workflow. A case study demonstrates the effectiveness of this approach, showing that the average relative deviation from evacuation simulation results is less than 10%. The method is particularly well suited for evaluating designs during the early stages. This research offers a novel perspective for evacuation analysis and provides a concise and reliable tool for the quantitative evaluation and performance optimization of building evacuation space. Full article

When a building normally used for exhibitions is converted into a Fangcang shelter hospital in emergency situations, its original space combination, functional flow line, and safety exits are significantly changed. When the building becomes densely populated, if an accident such as a fire, explosion, or earthquake occurs, then safe evacuation will be a serious challenge. This study systematically considers the characteristics of the building space and functional flow line after the conversion of an exhibition building to a Fangcang shelter hospital. Pathfinder software was used to simulate representative scenarios of a Fangcang shelter hospital and to analyze the main spatial factors affecting evacuation efficiency in terms of evacuation time, spatial congestion characteristics, and the exits used by personnel. Then, a targeted design optimization strategy was proposed based on the accessibility of safety exits and the internal space layout of the building. Finally, a simulation was used to verify the effectiveness of the design strategy. The results of this study provide solid theoretical support and methodological guidance for the spatial arrangement of exhibition buildings converted into Fangcang shelter hospitals so as to effectively improve the efficiency of safe evacuation and promote the resilience and safety of exhibition buildings. Full article

Global optimization problems, ubiquitous scientific research, and engineering applications necessitate sophisticated algorithms adept at navigating intricate, high-dimensional search landscapes. The Escape (ESC) algorithm, inspired by the complex dynamics of crowd evacuation behavior—where individuals exhibit calm, herding, or panic responses—offers a compelling nature-inspired paradigm for addressing these challenges. While ESC demonstrates a strong intrinsic balance between exploration and exploitation, opportunities exist to enhance its inter-agent communication and search trajectory diversification. This paper introduces an advanced bio-inspired algorithm, termed Crisscross Escape Algorithm (CCESC), which strategically incorporates a Crisscross (CC) information exchange mechanism. This CC strategy, by promoting multi-directional interaction and information sharing among individuals irrespective of their behavioral group (calm, herding, panic), fosters a richer exploration of the solution space, helps to circumvent local optima, and accelerates convergence towards superior solutions. The CCESC’s performance is extensively validated on the demanding CEC2017 benchmark suites, alongside several standard engineering design problems, and compared against a comprehensive set of prominent metaheuristic algorithms. Experimental results consistently reveal CCESC’s superior or highly competitive performance across a wide array of benchmark functions. Furthermore, CCESC is effectively applied to a complex reservoir production optimization problem, demonstrating its capacity to achieve significantly improved Net Present Value (NPV) over other established methods. This successful application underscores CCESC’s robustness and efficacy as a powerful optimization tool for tackling multifaceted real-world problems, particularly in reservoir production optimization within complex sedimentary environments. Full article

Metropolitan city express line tunnels are fully enclosed and often span long distances between stations, allowing multiple trains within a single interval. Traditional segmented ventilation ensures only one train per section, but ultra-long tunnels with shaftless designs introduce new challenges under fire conditions. This study investigates smoke behavior in an ultra-long inter-district tunnel during multi-train blockage scenarios. A numerical model evaluates the effects of train spacing, fire source location, and receding spacing on smoke back-layering, temperature distribution, and flow velocity. Results indicate that when train spacing exceeds 200 m and longitudinal wind speed is above 1.2 m/s, the impact of train spacing on smoke back-layering becomes negligible. Larger train spacing increases back-layering under constant wind speed, while higher wind speeds reduce it. Fire source location and evacuation spacing affect the extent and pattern of smoke spread and high-temperature zones, especially under reverse ventilation conditions. These findings provide quantitative insights into fire-induced smoke dynamics in ultra-long tunnels, offering theoretical support for optimizing ventilation control and evacuation strategies in urban express systems. Full article