200 research outputs found
Self-organized crowd dynamics : research on earthquake emergency response patterns of drill-trained individuals based on GIS and multi-agent systems methodology
Predicting evacuation patterns is useful in emergency management situations such as an earthquake. To find out how pre-trained individuals interact with one another to achieve their own goal to reach the exit as fast as possible firstly, we investigated urban peopleâs evacuation behavior under earthquake disaster conditions, established crowd response rules in emergencies, and described the drill strategy and exit familiarity quantitatively through a cellular automata model. By setting different exit familiarity ratios, simulation experiments under different strategies were conducted to predict peopleâs reactions before an emergency. The corresponding simulation results indicated that the evacueesâ training level could affect a multi-exit zoneâs evacuation pattern and clearance time. Their exit choice preferences may disrupt the exit optionsâ balance, leading to congestion in some of the exits. Secondly, due to peopleâs rejection of long distances, congestion, and unfamiliar exits, some people would hesitant about the evacuation direction during the evacuation process. This hesitation would also significantly reduce the overall evacuation efficiency. Finally, taking
a community in Zhuhai City, China, as an example, put forward the best urban evacuation drill strategy. The quantitative relation between exit familiar level and evacuation efficiency was obtained. The final results showed that the optimized evacuation plan could improve evacuationâs overall efficiency through the self-organization effect. These studies may have some impact on predicting crowd behavior during evacuation and designing the evacuation plan
Environmental effect on egress simulation
Abstract. Evacuation and egress simulations can be a useful tool for studying the effect of design decisions on the flow of agent movement. This type of simulation can be used to determine before hand the effect of design decisions and enable exploration of potential improvements. In this work, we study at how agent egress is affected by the environment in real world and large scale virtual environments and investigate metrics to analyze the flow. Our work differs from many evacuation systems in that we support grouping restrictions between agents (e.g., families or other social groups traveling together), and model scenarios with multiple modes of transportation with physically realistic dynamics (e.g., individuals walk from a building to their own cars and leave only when all people in the group arrive).
Agent-Based Simulation and Analysis of Human Behavior towards Evacuation Time Reduction
Human factors play a significant part in the time taken to evacuate following an
emergency. An agent-based simulation, using the Prometheus methodology (SEEP
1.5), has been developed to study the complex behavior of human (the âagentsâ) in
high-rise buildings evacuations. In the case of hostel evacuations, simulation results
show that pre-evacuation phase takes 60.4% of Total Evacuation Time (TET). The
movement phase (including queuing time) only takes 39.6% of TET. From sensitivity
analysis, it can be shown that a reduction in TET by 41.2% can be achieved by
improving the recognition phase. Exit signs have been used as smart agents.
Expanded Ant Colony Optimization (ACO) was used to determine the feasible
evacuation routes. Both the âfamiliarity of environmentâ wayfinding method, which is
the most natural method, and the ACO wayfinding, have been simulated and
comparisons made. In scenario 1, where there were no obstacles, both methods
achieved the same TET. However, in scenario 2, where an obstacle was present, the
TET for the ACO wayfinding method was 21.6% shorter than that for the âfamiliarityâ
wayfinding method
An operational research-based integrated approach for mass evacuation planning of a city
Large-scale disasters are constantly occurring around the world, and in many cases evacuation of regions of city is needed. âOperational Research/Management Scienceâ (OR/MS) has been widely used in emergency planning for over five decades. Warning dissemination, evacuee transportation and shelter management are three âEvacuation Support Functionsâ (ESF) generic to many hazards. This thesis has adopted a case study approach to illustrate the importance of integrated approach of evacuation planning and particularly the role of OR/MS models. In the warning dissemination phase, uncertainty in the householdâs behaviour as âwarning informantsâ has been investigated along with uncertainties in the warning system. An agentbased model (ABM) was developed for ESF-1 with households as agents and âwarning informantsâ behaviour as the agent behaviour. The model was used to study warning dissemination effectiveness under various conditions of the official channel. In the transportation phase, uncertainties in the householdâs behaviour such as departure time (a function of ESF-1), means of transport and destination have been. Households could evacuate as pedestrians, using car or evacuation buses. An ABM was developed to study the evacuation performance (measured in evacuation travel time). In this thesis, a holistic approach for planning the public evacuation shelters called âShelter Information Management Systemâ (SIMS) has been developed. A generic allocation framework of was developed to available shelter capacity to the shelter demand by considering the evacuation travel time. This was formulated using integer programming. In the sheltering phase, the uncertainty in household shelter choices (either nearest/allocated/convenient) has been studied for its impact on allocation policies using sensitivity analyses. Using analyses from the models and detailed examination of household states from âwarning to safetyâ, it was found that the three ESFs though sequential in time, however have lot of interdependencies from the perspective of evacuation planning. This thesis has illustrated an OR/MS based integrated approach including and beyond single ESF preparedness. The developed approach will help in understanding the inter-linkages of the three evacuation phases and preparing a multi-agency-based evacuation planning evacuatio
Role of opinion sharing on the emergency evacuation dynamics
Emergency evacuation is a critical research topic and any improvement to the existing evacuation models will help in improving the safety of the evacuees. Currently, there are evacuation models that have either an accurate movement model or a sophisticated decision model. Individuals in a crowd tend to share and propagate their opinion. This opinion sharing part is either implicitly modeled or entirely overlooked in most of the existing models. Thus, one of the overarching goal of this research is to the study the effect of opinion evolution through an evacuating crowd. First, the opinion evolution in a crowd was modeled mathematically. Next, the results from the analytical model were validated with a simulation model having a simple motion model. To improve the fidelity of the evacuation model, a more realistic movement and decision model were incorporated and the effect of opinion sharing on the evacuation dynamics was studied extensively. Further, individuals with strong inclination towards particular route were introduced and their effect on overall efficiency was studied. Current evacuation guidance algorithms focuses on efficient crowd evacuation. The method of guidance delivery is generally overlooked. This important gap in guidance delivery is addressed next. Additionally, a virtual reality based immersive experiment is designed to study factors affecting individuals\u27 decision making during emergency evacuation
Multi-scale Models for Transportation Systems Under Emergency Conditions
The purpose of this study is to investigate human behavior in emergencies. More specifically, agent-based simulation and social force models were developed to examine the impact of various human and environmental factors on the efficiency of the evacuation process, through a series of case studies. The independent variables of the case studies include the number of exits, the number of passengers, the evacuation policies, and instructions, as well as the queue configuration and wall separators. The results revealed the location of the exits, number of exits, evacuation strategies, and group behaviors all significantly impact the total time of the evacuation. For the queue configuration, short aisles lower infection spread when rope separators were used. The findings provide new insights in designing layout, planning, practice, and training strategies for improving the effectiveness of the pedestrian evacuation process under emergency
Adaptive cell-based evacuation systems for leader-follower crowd evacuation
The challenge of controlling crowd movement at large events expands not only to the realm
of emergency evacuations but also to improving non-critical conditions related to operational
efficiency and comfort. In both cases, it becomes necessary to develop adaptive crowd motion
control systems. In particular, adaptive cell-based crowd evacuation systems dynamically
generate exit-choice recommendations favoring a coordinated group dynamic that improves
safety and evacuation time. We investigate the viability of using this mechanism to develop
a ââleader-followerââ evacuation system in which a trained evacuation staff guides evacuees
safely to the exit gates. To validate the proposal, we use a simulationâoptimization framework
integrating microscopic simulation. Evacueesâ behavior has been modeled using a three-layered
architecture that includes eligibility, exit-choice changing, and exit-choice models, calibrated
with hypothetical-choice experiments. As a significant contribution of this work, the proposed
behavior models capture the influence of leaders on evacuees, which is translated into exitchoice
decisions and the adaptation of speed. This influence can be easily modulated to evaluate
the evacuation efficiency under different evacuation scenarios and evacueesâ behavior profiles.
When measuring the efficiency of the evacuation processes, particular attention has been paid
to safety by using pedestrian Macroscopic Fundamental Diagrams (p-MFD), which model the
crowd movement dynamics from a macroscopic perspective. The spatiotemporal view of the
evacuation performance in the form of crowd-pressure vs. density values allowed us to evaluate
and compare safety in different evacuation scenarios reasonably and consistently. Experimental
results confirm the viability of using adaptive cell-based crowd evacuation systems as a guidance
tool to be used by evacuation staff to guide evacuees. Interestingly, we found that evacuation
staff motion speed plays a crucial role in balancing egress time and safety. Thus, it is expected
that by instructing evacuation staff to move at a predefined speed, we can reach the desired
balance between evacuation time, accident probability, and comfort
e-Sanctuary: open multi-physics framework for modelling wildfire urban evacuation
The number of evacuees worldwide during wildfire keep rising, year after year. Fire evacuations at the wildland-urban interfaces (WUI) pose a serious challenge to fire and emergency services and are a global issue affecting thousands of communities around the world. But to date, there is a lack of comprehensive tools able to inform, train or aid the evacuation response and the decision making in case of wildfire. The present work describes a novel framework for modelling wildfire urban evacuations. The framework is based on multi-physics simulations that can quantify the evacuation performance. The work argues that an integrated approached requires considering and integrating all three important components of WUI evacuation, namely: fire spread, pedestrian movement, and traffic movement. The report includes a systematic review of each model component, and the key features needed for the integration into a comprehensive toolkit
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