Emergency Evacuation Research Articles

Extended Floor Field Cellular Automata Model for Pedestrian Emergency Evacuation Considering Panic Emotion

Panic emotion appears frequently in an emergency evacuation, affecting evacuation efficiency and pedestrian safety. Individual diversity in emotion propagation causes pedestrians to behave differently. To better describe the emotion propagation in the movement of pedestrians, we analyze the characteristics of the emotions of different pedestrians in emergencies. Considering pedestrian heterogeneity, we divide pedestrians into three types (conservative, moderate, and radical) according to the strength of the expression of individual emotions. Based on an analysis of the characteristics of the three types of pedestrian, an improved susceptible-infected-recovered (SIR) model is built to describe the pedestrian emotion propagation process. In addition, a conflict avoidance method that considers pedestrian speed is proposed to demonstrate pedestrian motion more realistically. Based on this foundation, a cellular automata (CA) model that integrates emotion propagation and conflict avoidance techniques is employed to replicate the process of pedestrian emergency evacuation. The simulation results suggest that a higher proportion of pedestrians with initial panic emotions and a radical behavior type leads to a prolonged evacuation time. Many pedestrians in emergency evacuations gather at the exit in a short time (approximately 37 time steps), the density then reaches a high-level (approximately 5.5 pedestrians/m2) for a period of time, and the duration increases with the increase in the number of pedestrians. Methods for guiding pedestrians to evacuate in a rational manner are worthy of promotion and research.

Enhanced Manual Ventilation with a Handheld Audiovisual Device - BENGI - Insights from a Pilot Study in Special Operations Medicine.

In emergency casualty and evacuation situations, manual ventilation using self-inflating bags remains a critical skill; however, significant challenges exist in ensuring safety and effectiveness, since inaccurate manual ventilation is associated with life-threatening risks (e.g., gastric insufflation with aspiration, barotrauma, and reduced venous return). This study assessed the impact of audiovisual feedback from the bag-valve-mask (BVM) emergency narration guided instrument (BENGI), a handheld manual ventilation guidance device, on improving performance and safety, immediately and 2 weeks after, with no additional manual ventilation training. In a crossover manikin simulation study with 20 participants, BENGI immediately and significantly improved tidal volume and respiratory rate accuracy. Intraand inter-participant variations were lower with BENGI, with Poincaré plot analysis showing improved performance that remained for at least 2 weeks following BENGI training. BENGI's audiovisual feedback improves manual immediately and persistently, making it invaluable for training and clinical use in diverse scenarios, from battlespace to civilian emergencies.

A novel extended social force model for studying the impact of the heterogeneity of pedestrian physical fitness on emergency evacuation efficiency

Emergencies in public places, particularly confined crowded areas, will disrupt the stability of dense crowds and consequently lead to accidents. To promote public emergency safety, there is a pressing need for efficient modeling methods to investigate the evacuation mechanism in these places and improve the social public safety. This study proposes a Physical Fitness Heterogeneity based Social Force Model (PFH-SFM) that takes into account the heterogeneous desired evacuation velocity caused by the heterogeneity of pedestrian physical fitness, by means of developing the normalized desired velocity ratio. Then, we use PFH-SFM to investigate the relationships between the escape rate and the desired velocity, and between the evacuation duration and the desired velocity in terms of various group sizes with heterogeneous physical fitness, the relationship between the percentage of reduction in evacuation duration and desired velocity when including weak pedestrians, the pedestrian distribution in the evacuation process, the relationship between the total evacuation duration and the desired velocity in terms of various proportions of weak pedestrians and the relationship between the evacuation duration and the desired velocity in terms of various normalized starting and ending velocity ratios by considering various group sizes, respectively. The findings of this study show that the existence of a certain small proportion of pedestrians with weak physical fitness can promote global evacuation dynamics, especially in the case of high crowded density, and can reduce evacuation duration by up to 20% in our experiments. Additionally, when the percentage of pedestrians with weak physical fitness is relatively high, they tend to have a detrimental effect on the evacuation efficiency. Furthermore, there exists a moderate normalized desired starting velocity ratio that maximizes the overall evacuation efficiency; on the other hand, the lower the normalized desired ending velocity ratio is, the more efficient the evacuation is. To the best of the authors’ knowledge, this study is the first time to introduce the concepts of normalized desired starting and ending velocity ratios and innovatively analyzes the impact of the continuously changing desired velocity of pedestrians on the evacuation efficiency in multi-exit scenarios. The results offer valuable insights for relevant stakeholders to formulate effective evacuation plans, so as to enhance urban emergency capacity and minimize social and economic losses.

Fire emergency management of large shopping malls: IoT-based evacuee tracking and dynamic path optimization

As urbanization accelerates and buildings become more complex, fire emergency evacuation has become increasingly challenging. Traditional evacuation plans often struggle with slow response times and suboptimal path planning in real-time dynamic and complex fire scenarios. To address these issues, this study proposes the IoT-based DWM-Evac model for fire emergency evacuation path planning. The model leverages IoT technology by using various sensors placed inside buildings to monitor fire incidents and spread in real-time, collecting critical data such as temperature, smoke concentration, and flame location. It integrates Dynamic Graph Neural Networks (DGNN), Whale Optimization Algorithm (WOA), and Markov Decision Process (MDP) to enhance path efficiency and safety. Experimental results indicate that the DWM-Evac model achieves an average evacuation time of 315 s in a virtual mall environment, 25 s shorter than traditional plans, with an average path length of 255 meters and a path safety score of 0.92, higher than the traditional plan’s 0.88. The application of IoT in fire emergency management not only improves response speed but also optimizes path planning, significantly enhancing personnel safety.

A Bayesian network-based probabilistic framework for seismic vulnerability assessment of road networks

After an earthquake, roadside debris from collapsed buildings, structural damage to bridges, and large-scale emergency evacuations are major obstructions to the connectivity of road networks (RNs). However, few studies have comprehensively examined the impact of all these obstructions on the seismic vulnerability of RNs while considering uncertainties. In this paper, a novel probabilistic framework is proposed for seismic vulnerability assessment of RNs based on Bayesian networks (BNs). Herein, the vulnerability of RNs is defined as a combination of the failure probability of a road link and its conditional consequences in terms of network dis-connectivity. The framework can be used to assess the effects of debris distributions, the functionality losses of bridges, and evacuation flows on the failure probabilities of road links and the seismic vulnerability of RNs. Uncertainties in the post-earthquake damage states of buildings and bridges, building collapse types, building-to-road distances, and travel costs are explicitly considered and propagated in the framework using Monte Carlo (MC) simulations. The MC results are used to establish prior probabilities, and based on bidirectional inference with BNs, it is possible to assess the seismic vulnerability of RNs and identify critical roads. The proposed methodology is verified through a real-world RN in China.

Septic Abortion at 17 Weeks Gestation after Radical Trachelectomy and Transabdominal Cerclage: A Case Report

Septic abortion can lead to severe maternal morbidity and mortality. The management of septic abortion can be complicated by a history of radical trachelectomy and transabdominal cerclage placement. A 33-year-old G1P0 at 17 weeks and 6 days gestation presented in severe septic shock after being diagnosed 6 days prior with previable rupture of membranes at an outside hospital and managed expectantly. History was notable for cervical adenocarcinoma status post radical trachelectomy and transabdominal cerclage placement. Due to uterine occlusion from the cerclage, the patient underwent emergent uterine evacuation via an abdominal approach. The risks and benefits of expectant management of pre-viable rupture of membranes in patients with abdominal cerclage should be weighed very cautiously. Among women with abdominal cerclage for whom uterine evacuation is indicated, a transabdominal approach may be necessary.

Efficiency Comparison between Simplified and Advanced Evacuation Analysis Models: A Case Study of Guryong Station, Republic of Korea

Modern subway systems have increased in size and complexity, and this growth presents significant challenges for planners of emergency evacuations. In this study, the effectiveness of the simplified and advanced evacuation analysis methods recommended by the International Maritime Organization (IMO) are evaluated for Guryong Station in Seoul, South Korea. The simplified evacuation analysis method facilitates rapid assessments by using general parameters, while the advanced evacuation analysis entails performing detailed simulations of human behavior and physical interactions. Our findings indicate that the results of the simplified evacuation analysis method are reasonably close to those of the more time-consuming advanced evacuation analysis method, thereby demonstrating the practical applicability of the former method for conducting initial evacuation safety assessments. Specifically, both the simplified and advanced methods showed a 20% reduction in Total Evacuation Time when tunnel evacuation routes were utilized. This finding demonstrates that the simplified method can produce results comparable to the advanced method, making it a reliable tool for initial assessments and for evaluating alternative strategies to reduce evacuation time. By demonstrating that the simplified evacuation analysis method can yield reliable results, we provide valuable insights for developing smart, resilient cities with efficient emergency-response capabilities.

Physical Fitness Determinants of a Military Casualty Evacuation Test.

Casualty evacuation has been identified as a typical and essential single military task which every soldier should be able to perform rapidly during combat. Previous studies suggest that casualty evacuation is typically conducted by dragging and demands e.g., lean body mass and anaerobic performance. Association of physical fitness with casualty evacuation by dragging has been studied widely but previous studies lack comprehensive assessment of all physical fitness determinants. The purpose of the present study was to examine comprehensively how casualty emergency evacuation (CEE) performance associates with physical fitness and body composition. A total of 25 conscripts (20 men, 5 women) volunteered for measurements of height, weight, waist circumference, body composition, 1-min sit-ups and push-ups, grip strength, isometric bench and leg press, standing long jump, 30-s cycle ergometer test, and 12-min run test. Subjects performed a CEE test in which evacuation time (ET), heart rate, blood lactate concentration, and rate of perceived exertion were measured. In the CEE test, subjects wore combat gear (11.7 ± 1.6 kg) and dragged a doll wearing combat gear (80.2 kg) 28 m while crawling (go round two cones, Z-pattern) and 20 m upright (straightforward). Correlations and backward regression analysis were used for statistical analyses. The level of significance was set to P ≤ .05. Evacuation time lasted on average 87 ± 32 s with a peak heart rate of 184 ± 6 bpm, lactate concentration of 9.4 ± 2.7 mmol/l, and RPE of 17 ± 1. Evacuation time correlated inversely and strongly with anaerobic capacity and power (r = -0.72-0.78, P ≤ .001), but not with aerobic fitness. Inverse and strong correlations were observed between ET and maximal strength variables (r = -0.58-0.69, P ≤ .01), whereas muscular endurance and ET revealed non-significant correlations. Evacuation time correlated moderate to strongly with body fat percentage (r = 0.48, P ≤ .05) and inversely with lean body mass (r = -0.74, P ≤ .001) and body height (r = -0.53, P ≤ .01). The backward regression analysis showed that anaerobic capacity (standardized β = -0.52, P ≤ .001), fat percentage (standardized β = 0.40, P ≤ .001), and isometric leg press (standardized β = -0.25, P ≤ .1) together explained the variance of ET significantly (adjusted R2 = 0.84, P ≤ .001). This study examined thoroughly how different physical fitness dimensions and body composition relate to a CEE test performed by a combination of dragging while crawling and in upright position. Casualty emergency evacuation was discovered as a high-intensity military task, which demands most importantly high anaerobic performance, lean body mass, and maximal strength capabilities. Improving these dimensions of physical fitness should be considered highly important as CEE is essential and possibly one of the most demanding military tasks which every soldier should be able to conduct in combat. From operational perspective, it is relevant that soldiers are able to perform CEE during operations; therefore, further research is needed on how acute operational stress changes the nature of CEE and its physical determinants.

Spatial Analysis with Detailed Indoor Building Models for Emergency Services

This paper presents a systematic approach to perform spatial analysis with detailed indoor building models for emergency service decision supports. To achieve a more realistic spatial application, this research integrates three-dimensional (3D) indoor building models and their attributes to simulate an emergency evacuation scenario. Indoor building models of a complicated train station with different levels of detail are generated from two-dimensional (2D) floor plans and Building Information Model (BIM) datasets. In addition to the 3D building models, spatial and non-spatial attributes are also associated with the created building models and the objects within them. The ant colony optimization (ACO) algorithm is modified to analyze the indoor building models for emergency service decision support applications. The detailed indoor models and the proposed spatial analysis algorithms are tested in simulated emergency evacuation scenarios to select the best routes during emergency services. The experimental results demonstrate that the proposed system is helpful for selecting the optimal route with the least cost at varying time stamps. Together with the developed spatial analysis framework, they have a great potential for effective decision support during emergency situations.

Simulation on passenger evacuation of metro train fire in the tunnel

The metro tunnel space is relatively closed, it is difficult to rescue after the metro train fire accident, which causes heavy casualties and property losses. Studying the safe evacuation of passengers under fire smoke spread has important significance. The numerical simulation methods are used to analyze the reliability of passenger evacuation in metro train fire scenarios. Firstly, the required safety evacuation time (RSET) calculation methods in short-distance and long-distance tunnels are developed combining the pre-action time and train response time. Then, a passenger evacuation model in metro trains is established in Pathfinder software to simulate the evacuation process under different passenger loads, carriage layouts, evacuation strategies, and train locations. The simulation results show that the RSET is affected by passenger load, seat arrangement, evacuation strategies and train locaitons. The critical point calculation method effectively finds out the critical point of the train location, which guides emergency evacuation strategies in fire scenarios.

Understanding fire combustion characteristics and available safe egress time in underground metro trains: A simulation approach

Due to insufficient oxygen supply in the tunnel, incomplete combustion of the underground metro train fire easily produces toxic gases and smoke dust, causing difficulty in breathing for passengers and rescue. The experimental study of the fire combustion characteristics of metro trains in the tunnel is of great significance for designing metro fire extinguishing and fire prevention systems and providing reliable guidance for emergency evacuation in fire scenarios. A train fire model is established to study the effects of various factors on fire combustion characteristics and calculate the available safe egress time (ASET). The smoke spread characteristics under different conditions such as fire source power, fire source location, carriage layout, and train location are simulated. The simulation results show that the fire source power, location, and seat arrangement have a significant impact on the smoke spread characteristics of carriage fires and ASET.

Multi-Objective Real-Time Planning of Evacuation Routes for Underground Mine Fires

When a fire occurs underground, pre-existing emergency escape routes may become ineffective. Such scenarios necessitate the real-time planning of escape routes that consider evolving conditions and prioritize safety. This paper proposes a multi-objective real-time search method for emergency escape routes using dynamic programming to address these challenges. Firstly, this paper discusses how the evacuation of an underground mine fire caused by external factors depends on the fire monitoring system, personnel positioning system, and emergency evacuation system, as well as the modeling and solution methods of evacuation route planning. Then, based on fire smoke, CO, and temperature sensor data from the mine ventilation network structure and monitoring system, the possible smoke spread in the event of an underground fire was calculated. The objectives are to optimize both the shortest equivalent length of the path and the shortest time to walk through the smoke flow while ensuring that temporary escape time does not exceed the rated protection time of the self-rescuer. A mathematical model for emergency escape route planning is established under these conditions. A labeling algorithm based on dynamic programming is employed to find the Pareto optimal solution set of emergency evacuation routes that meet emergency requirements. Finally, two path evaluation indicators, namely “escape target priority” and “personnel temporary escape time”, are introduced to re-rank the solutions in the Pareto optimal set, thereby obtaining disaster evacuation routes with different priorities. Example verification shows that the algorithm can quickly solve the disaster evacuation routes that meet the actual disaster evacuation needs in complex networks. Example verification shows that the algorithm can quickly solve the emergency escape routes in complex networks that meet actual emergency escape needs.

Effects of Continuous Prenatal Low Dose Rate Irradiation on Neurobehavior, Hippocampal Cellularity, Messenger RNA and MicroRNA Expression on B6C3F1 Mice.

Epidemiological, experimental, and ecological data have indicated the controversial effect of in utero chronic low dose rate (<6 mGy/h) with accumulative low (≤100 mGy) or high (>100 mGy) dose radiation exposure. Our main goal of this study was to examine if different low dose rates of chronic pre- and/or post-natal radiation exposure with accumulative high doses could induce hippocampal cellular, mRNA, and miRNA changes leading to neuropsychiatric disorders. The comprehensive mouse phenotypic traits, organ weight, pathological, and blood mRNA and miRNA changes were also studied. Using different approaches including SmithKline, Harwell, Imperial College, Royal Hospital, Phenotype Assessment (SHIRPA), neurobehavioral tests, pathological examination, immunohistochemistry, mRNA and miRNA sequencing, and real-time quantitative polymerase chain reaction (qRT-PCR) validation, we found that in prenatally irradiated (100 mGy/d for 18 days with an accumulative dose of 1.8 Gy) 1-year-old mice, no cellular changes, including immature neurons in the subgranular zone, mature neurons and glial cells in the hilus of the dentate gyrus and development of cognitive impairment, neuropsychiatric disorders, occurred. However, a significant reduction in body weight and mass index (BMI) was indicated by the SHIRPA test. A reduced exploratory behavior was shown by an open field test. Organ weights showed significant reductions in the testes, kidneys, heart, liver and epididymides with no abnormal pathology. mRNA and miRNA sequencing and qRT-PCR validation revealed the upregulation of Rubcnl and Abhd14b, and downregulation of Hspa1b, P4ha1, and Banp genes in both the hippocampus and blood of mice prenatally irradiated with 100 mGy/d. Meanwhile, downregulation of miR-448-3p and miR1298-5p in the hippocampus, miR-320-3p, miR-423-5p, miR-486b-5p, miR-486b-3p, miR-423-3p, miR-652-3p, miR-324-3p, miR-181b-5p, miR-let-7b, and miR-6904-5p in the blood was induced. The target scan revealed that Rubcnl is one of the miR-181b-5p targets in the blood. We, therefore, concluded that prenatal chronic irradiation with a low dose rate of 100 mGy/d and accumulative dose of 1.8 Gy or below might not induce significant adverse health effects on the offspring. Further study of different low dose rate radiation exposures with accumulative high doses may provide threshold doses for authorities or regulators to set new radiation safety guidelines to replace those extrapolated from acute high dose/dose rate irradiation to reduce unnecessary emergency evacuation or spending once a nuclear accident or leakage occurs.

Numerical simulation study on propane gas leakage and diffusion law in slope terrain

AbstractIt is frequent that gas leakage accidents occur at chemical enterprises located in slope terrain. Meet the requirement of urgently studying the gas leakage and diffusion law in slope terrain. In this study, we utilize computational fluid dynamics (CFD) to simulate the scenarios of propane leakage and diffusion under four distinct slope conditions, which are 0°, 10°, 15°, and 20°. The gas diffusion law under different slopes is investigated, and the influence of wind speed and wind direction on the diffusion process is also further analyzed. The study indicates that when the slope exceeds 15°, the change in slope exerts a pronounced influence on the dispersion of propane leakage. Compared with diffusion on flat ground, there is a distinct propane aggregation area at the bottom of the slope terrain. Also, the steeper the slope, the more noticeable the aggregation phenomenon. The increase of wind speed makes propane gas lifted, and the gas aggregation at the bottom of the slope decreases. In particular, at a wind speed of 3.3 m/s, the aggregation of propane at the bottom of the first 15° and 20° slopes is more pronounced. Under the upwind condition, the propane gas is entrained at the slope surface, increasing the propane concentration in the area around the tank, which in turn increases the safety risk. The findings of this study have significant implications for the rational layout of chemical enterprises, gas leakage monitoring, and emergency evacuation planning for leakage accidents. They can also help enhance chemical enterprises' safety prevention abilities and the efficiency of their emergency response.

A novel multi-source information fusion method for emergency spatial resilience assessment based on Dempster-Shafer theory

In the midst of today's intricate and ever-changing natural and social landscape, this study is committed to proposing a novel multi-source information fusion method for assessing the spatial resilience of urban emergency evacuation and rescue. Its overarching aim is to uncover latent challenges and contribute to the enhancement of a city's capacity to respond to emergencies. To achieve this, we have devised a comprehensive assessment indicator system, capable of not only quantifying a city's spatial resilience but also offering indispensable guidance for urban emergency evacuation and rescue spatial planning. Furthermore, we have introduced an innovative evaluation methodology framework. This framework includes the establishment of the basic probability assignment (BPA) model, a pioneering method for generating BPA for observed values, and the novel application of hierarchical weighting and fusion techniques. By extending the Dempster-Shafer theory, we have not only enhanced the method's ability to express and integrate uncertain information but also significantly improved the precision of the evaluation. Ultimately, we conducted a quantitative assessment using Shenzhen, China, as a case study, identifying existing issues and proposing highly-targeted improvement strategies. These research findings not only provide robust support for the augmentation of urban emergency capabilities in Shenzhen but also offer pioneering insights for the quantitative assessment and advancement of emergency spatial resilience in cities across the globe.

The Impact of Persuasive Communication, Transformational Leaderships, and Work Interest on Work Ethic

The Yogyakarta City Fire Department is located on Jl. Muja Muju. Umbulharjo, Yogyakarta City, is an implementing element of the government that has the responsibility of assisting the community in handling fires and rescues. In addition to extinguishing fires, firefighters are also trained to carry out evacuations such as accidents, natural disasters, and other emergency evacuations. So the importance of competent and qualified human resources (HR) is needed to support the work ethic and activities so that the mission of the company or an organization can succeed. This study aims to prove and collect empirical evidence that Persuasive Communication, Transformational Leadership, and Work Interest affect the Work Ethic of Employees of the Fire and Rescue Service of Yogyakarta City. By conducting this study, the researcher hopes that the results of this study can be an evaluation in improving the performance and work ethic of the relevant agencies. This type of quantitative research with 67 respondents, using a purposive sampling method. Data was collected using a questionnaire and Likert scale as a measurement. The results of the study partially and simultaneously all variables, namely Persuasive Communication, Transformational Leadership, and Work Interest, have a positive and significant effect on the Work Ethic.

Individual route choice behavior in evacuation considering avoidance and phototropism: An experimental study

During an emergency evacuation in a building, participants' evacuation signs obedience behaviors have a significant impact on evacuation efficiency, while participants' possible phototropism and hazard avoidance behaviors occur during evacuation, which will affect evacuation efficiency. To investigate the effects of participants' phototropism and hazard avoidance behaviors on compliance with evacuation signs. One pre-experiment and four groups of evacuation experiments were conducted in the T-junction and Room of the building with a total of 170 participants. A fumes generator and searchlight to simulate light and fumes conditions under fire. Using the statistical analysis to explore the differences in the route choice behavior of evacuees under different conditions. The results show that: (1) In the natural state, participants showed significant phototropism and hazard avoidance. (2) Phototropism and hazard avoidance affect participants' obedience to evacuation signs. (3) In the room scene, participants demonstrated more obvious phototropism and hazard avoidance, even deviating from the evacuation sign's guidelines；(4) Participants showed some decision inertia during two consecutive decisions. Further combined with SHAP interpretable machine learning for analysis, it was found that (1) Scene conditions exist for phototropism and hazard avoidance in evacuees. (2) Fumes prevented participants' obedience to the evacuation sign, whereas light promoted participants' obedience to the sign. This indicates that evacuation signs need to be installed regarding the actual building structure. These findings can be used as theoretical references for building safety design, campus safety, and evacuation simulation tests.

Synergetic Decision-Making: Analyzing the Interplay of Human Behavior and Physical Infrastructure in Emergency Evacuations via an Analytical Approach

Synergetic Decision-Making: Analyzing the Interplay of Human Behavior and Physical Infrastructure in Emergency Evacuations via an Analytical Approach

Portable ultrasound-guided keyhole evacuation of intracerebral hemorrhage: a detailed case report highlighting technical nuances.

Intracerebral hemorrhage (ICH) is a common neurosurgical emergency that is associated with high morbidity and mortality. Minimally invasive or endoscopic hematoma evacuation has emerged in recent years as a viable alternative to conventional large craniotomies. However, accurate trajectory planning and placement of the tubular retractor remains a challenge. We describe a novel technique for handheld portable ultrasound-guided minimally invasive endoscopic evacuation of supratentorial hematomas. A 64-year-old male diagnosed right hematoma (48.5 mL) at the basal ganglia was treated with emergent ultrasound-guided endoscopic transtubular evacuation through a small craniotomy. Ultrasound-guidance facilitated optimal placement of the tubular retractor into the long axis of the hematoma, and allowed for near-total evacuation, reducing iatrogenic tissue damage by mitigating the need for wanding or repositioning of the retractor. The emergence of a new generation of small portable phased array ultrasound probes with improved resolution and clarity has broadened ultrasound's clinical applications.

The Knowledge of Safe Emergency Evacuation During an Earthquake Among the Residents of Tehran, Iran

The Knowledge of Safe Emergency Evacuation During an Earthquake Among the Residents of Tehran, Iran