Fault tree analysis (FTA) is one of the important analysis methods of safety system engineering commonly utilized in various industries to evaluate and improve the reliability and safety of complex systems. To grasp the current situation and development trend of FTA research and to further point out FTA’s future development directions, 1469 FTA-related articles from the literature were retrieved from the SCIE and SSCI databases. Informetric methods, including co-authorship analysis, co-citation analysis and co-occurrence analysis, were adopted for analyzing the cooperation relationship, research knowledge base, research hotspots and frontier in the FTA research field. The results show that China has the highest number of publications, and the Loughborough University of England has the highest number of publications of relevant institutions. Dynamic fault tree analysis, fuzzy fault tree analysis and FTA based on binary decision diagrams are recognized as the knowledge bases in FTA studies. “Reliability Engineering and System Safety”, “Safety Science” and “Fuzzy Sets and Systems” are the core journals in this field. Fuzzy fault tree analysis, dynamic fault tree analysis based on Bayesian networks and FTA combined with management factors may be both the main research hotspots and the frontiers. Then, by deriving the above results, this study can help scholars better master the current research status and frontiers of FTA to improve system reliability and safety.

Public health emergency management has been one of the main challenges of social sustainable development since the beginning of the 21st century. Research on public health emergency management is becoming a common focus of scholars. In recent years, the literature associated with public health emergency management has grown rapidly, but few studies have used a bibliometric analysis and visualization approach to conduct deep mining and explore the characteristics of the public health emergency management research field. To better understand the present status and development of public health emergency management research, and to explore the knowledge base and research hotspots, the bibliometric method and science mapping technology were adopted to visually evaluate the knowledge structure and research trends in the field of public health emergency management studies. From 2000 to 2020, a total of 3723 papers related to public health emergency management research were collected from the Web of Science Core Collection as research data. The five main research directions formed are child prevention, mortality from public health events, public health emergency preparedness, public health emergency management, and coronavirus disease 2019 (COVID-19). The current research hotspots and frontiers are climate change, COVID-19 and related coronaviruses. Further research is needed to focus on the COVID-19 and related coronaviruses. This study intends to contribute inclusive support to related academia and industry in the aspects of public health emergency management and public safety research, as well as research hotspots and future research directions.

A bibliometric analysis of relevant literature was conducted using co-occurrence, clustering, co-citation, and other analysis techniques to understand the state of research in areas related to subway fires. According to the research findings, the primary areas of focus for subway fire research hotspots include fire behavior and smoke control, ventilation and smoke management, evacuation and personnel safety, fire tolerance and fire protection materials, simulation and modeling technology, climate change, and control systems. The optimization of ventilation modes, the development of simulation technology, the advancement of fireproof materials, the integration of artificial intelligence and social force models in evacuation models, and the impact of environmental and climate change on subway fires are the current research frontiers. The disciplines of environmental science, material engineering, social science, and artificial intelligence are increasingly intersecting with the research of subway fires. More cross-disciplinary cooperation will be beneficial for future research. These findings help researchers in rapidly comprehending the general state of situations regarding subway fires.

To gain a comprehensive understanding of the current research landscape in the field of new energy vehicle (NEV) fires and to explore its knowledge base and emerging trends, bibliometric methods—such as co-occurrence, clustering, and co-citation analyses—were employed to examine the relevant literature. A research knowledge framework was established, encompassing four primary themes: thermal management and performance optimization of power batteries, battery materials and their safety characteristics, thermal runaway (TR) and fire risk assessment, and fire prevention and control strategies. The key research frontiers in this domain could be classified into five categories: mechanisms and propagation of TR, development of high-safety battery materials and flame-retardant technologies, thermal management and thermal safety control, intelligent early warning and fault diagnosis, and fire suppression and firefighting techniques. The focus of research has gradually shifted from passive identification of causes and failure mechanisms to proactive approaches involving thermal control, predictive alerts, and integrated system-level fire safety solutions. As the field advances, increasing complexity and interdisciplinary integration have emerged as defining trends. Future research is expected to benefit from broader cross-disciplinary collaboration. These findings provide a valuable reference for researchers seeking a rapid overview of the evolving landscape of NEV fire-related studies.

Longitudinal ventilation fans in extra-long submarine tunnels are usually arranged at both ends of the tunnel limited by the tunnel cross section, which is usually hindered by insufficient power caused by extra-long ventilation distances. In this paper, the conception of a ventilation mode is proposed that services the tunnel and cross passages, to provide auxiliary air supply to the main tunnel. Two critical factors have been analyzed on the premise of evacuation safety, which combine to affect the ventilation efficiency in the case of an accident inside the tunnel, these are: air volume within the service tunnel, and cross passage open numbers. FDS simulation software is used to simulate the tunnel model; consider the number of cross passages from one to four; and simulate the service tunnel airflow velocity of 0.7 m/s, 0.75 m/s, 0.85 m/s, 1.0 m/s and 1.3 m/s. The results show that when 1.3 m/s wind speed is applied at both ends of the service tunnel, and three cross passages are operated, 20 MW of fire smoke within the accident tunnel can be effectively controlled; additionally, the wind speed in the cross passage will not hinder the evacuation. The simulation results are verified by ventilation network calculation.

Full-jet longitudinal ventilation is widely used in urban tunnels for its structural simplicity and high cost-effectiveness, yet its overall efficiency is constrained by high energy consumption. This study systematically investigates the influence of jet fan diameter and outlet velocity on ventilation performance. A three-dimensional numerical model of a typical urban tunnel was developed using ANSYS Fluent. Parametric simulations were conducted by varying jet velocity from 20 m/s to 38 m/s and fan diameter from 500 mm to 1600 mm. Jet flow evolution and the underlying mechanisms governing ventilation efficiency, including pressure development, air entrainment, and cross-sectional flow uniformity were rigorously analyzed. Results indicate that for a 500 mm diameter fan, increasing jet velocity from 20 m/s to 38 m/s elevates the ventilation pressure coefficient from 16% to 66%. At a fixed velocity of 38 m/s, enlarging the diameter from 500 mm to 1600 mm further improves the pressure enhancement coefficient from 66% to 73%, with fan pressure gain exhibiting a quadratic relationship with diameter. The analysis demonstrates that higher jet velocities enhance both momentum thrust and ambient air entrainment, thereby strengthening the longitudinal airflow driving force. Concurrently, larger fan diameters widen the jet diffusion angle, producing a more uniform cross-sectional airflow with reduced stratification. These findings clarify the distinct yet interdependent roles of jet velocity and fan diameter in jet behavior and ventilation efficacy, offering quantitative guidance for fan selection and energy-efficient longitudinal ventilation design.