基于FDS和元胞自动机动态耦合的火灾疏散模型

为研究火灾场景下温度、烟气和CO浓度等灾害因子对疏散的影响,建立基于FDS和元胞自动机动态耦合的火灾疏散模型。将FDS的网格和元胞自动机的元胞一一对应,将由FDS运行得到的灾害数据通过Python等技术手段实时加载到元胞中,使灾害数据持续影响行人转移概率,从而实现灾害和疏散的动态耦合;以单层教学楼作为仿真场景进行模拟分析,对火源位置和热释放速率等因素进行讨论,得出这些因素对行人疏散进程的影响规律;将模型与传统软件和同类方案进行对比。研究表明,火灾导致的高温和烟气会影响行人对疏散路径和安全出口的选择;热释放速率越大,行人越早处于危险状态,同时处于危险状态的行人也越多;该模型相比传统疏散软件不仅能考虑火灾产生的致灾因子对行人疏散的动态影响,还能确定行人最早处于危险状态的位置和时间,并用可视化的方式表现出来。     

低能见度环境下多出口场馆人群疏散研究

为了提高多出口场馆人群疏散效率,针对低能见度环境下多出口场馆人群疏散问题,在基本的社会力模型上加入了领导者吸引力和能见度范围的限制,建立了低能见度环境下多出口场馆人群疏散仿真模型,研究低能见度条件下人群疏散行为及疏散领导者对疏散结果的影响。在改进的社会力模型中,每个待疏散人员只对能见度范围内的其他个体或墙壁存在心理作用力,并且只有疏散领导者和出口附近的个体能够准确地判断出口位置,而其他个体只能根据能见度范围内的环境信息或疏散领导者的领导进行疏散。仿真结果显示,该模型可以较好地模拟出低能见度环境下多出口场馆人群疏散情形,疏散领导者选择距离最近的出口为疏散方向,普通个体会跟随能见度范围内的大多数个体或疏散领导者进行疏散,且疏散领导者的存在和其初始位置的合理设定能够提高疏散效率。     

双向蚁群算法的智能消防疏散图路径规划

当前我国正处在城市发展高速时期,综合建筑不断涌现,这时可根据火灾实时信息自动调整疏散路径的智能消防疏散图应运而生。路径规划算法是智能消防疏散图的重点研究方向之一。针对智能消防疏散图需结合火场信息动态规划路径等问题,提出了一种改进双向蚁群算法。添加了双向搜索策略,提高了算法全局搜索能力;结合A*算法改进了初始信息素分布,减小了算法初期搜索盲目性;改进了信息素更新策略,提高了算法收敛速度;结合火场信息和转向惩罚系数对算法蒸发系数、启发函数和转移概率进行改进,降低了陷入局部最优风险,提高了算法搜索效率和路径平滑性,并有效避开了火灾影响区域。通过仿真验证了算法有效性。     

隧道火灾疏散模型实时仿真算法的实现

由于隧道火灾的人员疏散难题,提出一种基于网格选择的隧道火灾人员疏散模型算法,设计了人员类型、奔跑速度、奔跑方向、人员所在环境等疏散属性参数,建立基于网格化离散场变量和坐标值的仿真模型。该算法克服了常用的元胞自动机算法计算量大,实时仿真比较困难的缺点。最后,利用Open Inventor进行了计算机仿真,并应用该仿真模型进行了分析,从逃生通道对疏散时间的影响及诱导标志设计对疏散时间的影响两方面验证了模型的有效性,并可直观地为安全疏散设计提供理论依据。     

岛式站台地铁车站人员的安全疏散仿真研究

地铁成为现代城市不可或缺的交通工具。但其特殊的运营环境容易引发事故状态下地铁车站人员的安全疏散问题。以西安某岛式站台地铁车站为研究对象,运用Building Exodus软件分别从人群结构、出入口数量、楼梯宽度以及火灾情况下对地铁车站进行人员安全疏散的模拟仿真研究,通过建立地铁车站模型仿真出各场景下的疏散时间,并与《地铁设计规范》中公式计算所得到的结果进行比对。仿真结果较真实地反映了各因素对车站人员疏散能力的影响,得出楼梯的设计是整个疏散过程的瓶颈所在,并提出相关建议。     

Risk of fire emergency evacuation in complex construction sites: Integration of 4D-BIM,social force modeling,and fire quantitative risk assessment

Construction industry is claimed to be the fourth most dangerous sector by number of fatalities. In complex construction sites, emergency evacuation risk assessment is a challenging task due to their ever-changing nature. This study developed a model to analyze the risk of fire emergency occurrence, and risks which are associated with evacuation performance (in response to that emergency) through an integrated approach in complex construction sites. To analyze the evacuation scenarios more realistically, we utilized Social Force Model (SFM) simulation engine. Using SFM for simulating the evacuation of complex construction sites has not been adequately addressed in the literature. Microscopically simulating the evacuation scenarios for all workdays of the studied complex project required high computation efforts. To tackle this computation challenge, a parallel computing technique was coupled with SFM simulation engine. More importantly, in this paper site’s evacuation performance was evaluated multi-objectively considering evacuation time and evacuation safety. The construction site’s emergency scenarios were modeled by 4D-BIM, potential for trigger fire emergency was determined by a fire ignition Quantitative Risk Assessment (QRA) module, and site evacuation was simulated by SFM simulation engine. The proposed framework handled the collaboration of 4D-BIM, fire QRA module, and SFM engine. This research study benefited from data driven from a real mega project. The findings demonstrated that analyzing the risk of evacuation through an integrated approach by the proposed model could render more realistic results. The results also provided the project managers with a reliable safety decision-making support.     

基于元胞自动机的普通超市火灾疏散模型的构建

通过分析已有的元胞自动机理论,结合人员疏散的特点,构建了考虑出口吸引力、火灾排斥力、摩擦力、排斥力和从众吸引力的普通超市火灾疏散模型。该模型充分考虑了多个因素对疏散过程的影响,对影响因素进行归一化处理,以综合影响因素建立的元胞转移强度作为行人移动规则。针对超市疏散人数、出口宽度及相隔距离、从众心理对疏散时间的影响进行了研究,并采用仿真疏散软件Pathfinder+FDS对模型进行验证,说明疏散模型具有一定可信性。研究表明行人疏散时间随人数呈线性正相关,人数存在临界值;出口宽度越宽或出口越多疏散时间相对越短,当达到出口阈值时对疏散时间影响不大;在陌生疏散环境或紧急情况下适当的从众行为会提高疏散效率。     

基于多智能体的森林火灾人员疏散仿真

森林火灾发生时, 对在林火蔓延过程中灾区人员疏散进行建模与仿真能够检查疏散方案是否合理, 从而为合理救灾提供指导意义. 目前对人员疏散模拟与仿真虽然有很多研究, 但对于森林火灾下人员疏散尚缺乏合适的仿真模型, 给科学救助决策带来很大困难. 为此, 提出将多智能体引入森林火灾蔓延及灾区人员疏散模型研究中, 并借助于Repast平台进行仿真, 实验结果表明本文方法能够为森林火灾人员疏散模拟与仿真提供正确的解决途径.     

基于粒子群神经网络算法的交通枢纽火灾应急疏散评价

在构建交通枢纽火灾应急疏散评价系统的基础上,建立用粒子群优化算法（PS0）和BP神经网络相结合的混合算法来进行综合评价的模型。该模型全面考虑影响应急疏散的各种因素,将定性分析和定量分析相结合,使评价结果更符合实际、更可靠。实例计算结果表明：PSO-BP方法简便、通用,其结果符合运营实际,能很好的反应交通枢纽火灾状况下应急疏散的实施效果。     

试谈人工智能技术在模拟火灾人员疏散时的应用

随着近年来经济的发展,人口密度的不断增大,在火灾事件中疏散人员已成为减少火灾人员伤亡的重要手段。实际疏散演练因为耗费大量的人力物力和时间已经不能满足现实需求,传统的疏散模拟模型又不能全面再现火灾发生时的复杂状况,而使模拟结果和实际有一定差别。将人工智能技术引入火灾人群疏散模拟可以更加清晰真实地再现火灾发生时的实际疏散状况,为实际工作提供更为可靠的指导依据。     

一种用于大型建筑火灾中的应急疏散算法

大型建筑发生火灾后,在现场情况比较复杂的情况下,尽快选择一条既安全、疏散时间又短的疏散路线,是室内人员安全快速的撤离的重要保障。本文在最短路径算法的基础上,提出了一种有效的有计划的应急疏散算法。此算法能有效的缩短总疏散时间,并且综合考虑到实际人流密度以及不同的通道环境对疏散路径的影响,更好地符合应急疏散的实际需求。     

建筑物火灾中的人群疏散研究

建筑物火灾是我国频发的安全事故,所以应研究建筑物火灾人群安全疏散问题。由于在建筑物火灾中,人群疏散时出现拥堵,存在不安全因素,造成人员伤亡。针对在现有的研究中未考虑人员行为的影响,提出了智能体(Agent)的人群行为建模技术在建筑物火灾中的人群疏散仿真中的应用方法。仿真结果显示基于Agent的行为模型可以仿真出人员特性及决策过程对人群疏散的影响,弥补现有的人群疏散模型的不足。仿真结果证明,Agent的行为建模技术具有仿真火灾全过程中人员疏散行为的功能,适用于建筑物火灾中的人群优化疏散策略。     

Modeling an ontology on accessible evacuation routes for emergencies

Providing alert communication in emergency situations is vital to reduce the number of victims. However, this is a challenging goal for researchers and professionals due to the diverse pool of prospective users, e.g. people with disabilities as well as other vulnerable groups. Moreover, in the event of an emergency situation, many people could become vulnerable because of exceptional circumstances such as stress, an unknown environment or even visual impairment (e.g. fire causing smoke). Within this scope, a crucial activity is to notify affected people about safe places and available evacuation routes. In order to address this need, we propose to extend an ontology, called SEMA4A (Simple EMergency Alert 4 [for] All), developed in a previous work for managing knowledge about accessibility guidelines, emergency situations and communication technologies. In this paper, we introduce a semi-automatic technique for knowledge acquisition and modeling on accessible evacuation routes. We introduce a use case to show applications of the ontology and conclude with an evaluation involving several experts in evacuation procedures.     

Agent-CA的体育场馆人群疏散模型

根据体育场馆人群疏散的特点与规律,提出一种基于多智能体和元胞自动机相融合的大型体育场馆人群疏散模型（Agent-CA）。将元胞空间中被虚拟人个体占据的元胞视为一个独立的智能体,将元胞及其状态进行封装,扩展为具有自主性的智能体,通过设计各种人群疏散行为策略做为演化规则,实现个体的差异性以体现个人个性、体力、心理等对疏散行为的影响,对体育场馆的人群疏散进行仿真实验。结果表明,Agent-CA综合了多智能体和元胞自动机的优点,充分考虑了个体内在因素,更接近现实大型体育场馆的人群疏散情形,缩短了疏散时间。     

基于DI-Guy的校园消防训练仿真

针对高校人口密度大、难以高效组织消防训练、缺乏处理应急事件经验等问题,提出一种基于DI-Guy软件的虚拟仿真训练方法。首先利用MultiGen Creator软件建立校园三维模型并加载到DI-Guy的可视化窗口中进行构建,然后模拟火灾发生场景和消防疏散过程,最后对人群疏散方案效果进行数据分析,同时对仿真模拟过程中的一些关键技术,包括利用自定义模型建立、特效实现、人物的行为控制和碰撞检测等进行研究和应用。仿真结果表明,所提出的仿真模型能够合理地反映人群疏散情况,起到良好的展示作用,为校园应急事件在DI-Guy平台的仿真提供可行性方案。     

大型建筑物人员疏散仿真系统及实现

人员疏散仿真的关键是模型的选择,为了使仿真结果更加接近实际,基于元胞自动机模型,改进和优化了人员疏散仿真算法,设计了目标元胞选择算法,提出个体竞争力的定义和计算方法,在疏散仿真模型中引入环境熟悉程度和运动方向等因子,设计并实现了疏散仿真系统,实验结果表明,系统能够更加真实地仿真紧急状况下人员疏散的全过程.     

A BIM-based simulation framework for fire safety management and investigation of the critical factors affecting human evacuation performance

Fire hazards are a big threat to human life and property safety. The U.S. fire statistics reveal that, in 2017 alone, 1,319,500 fires caused 3400 deaths and 14,670 injuries, which resulted in a loss of $23 billion [1]. Effective evacuation planning in densely occupied buildings should be primarily put in place if both the number of injuries/fatalities and the level of property loss are to be minimized. However, it is not realistic, and is unethical to study human evacuation performance under a burning building. For this reason, computational tools tend to be the best approach for simulating fire growth as well as human response to fire hazards. This study aims to develop a BIM-based simulation framework that implements the Fire Dynamic Simulator (FDS) and agent-based modeling (ABM) for simulating fire growth and evacuation performance for different building layout scenarios. An experimental implementation is conducted to validate the proposed framework, which verified the benefits of (1) using BIM to offer a platform for conducting simulation design and visualizing the simulation results of (a) hazardous fire zones and (b) effective escape routes; (2) simulating fire growth using the FDS tool; (3) developing an agent-based model that accounts for the critical factors affecting evacuation performance; and (4) applying a statistical analysis for investigating the effects of influential parameters from the proposed model. As a result, the simulation outputs can be used to optimize the building design and to investigate the influential factors on human evacuation efficiency. The proposed framework contributes to building fire safety management by enabling to minimize both injuries/fatalities and property loss.     

贪心选择在地铁站内行人疏散中的应用

大型室内场所空间布局较为复杂(如地铁站), 人群的高密度聚集往往存在一些潜在的风险. 本文在分析国内外人群快速疏散研究现状的基础上, 提出了一种基于贪心选择的行人疏散方法. 该方法以地铁站内复杂场景作为研究背景: 首先, 针对地铁站内的行人的行动轨迹难以获取问题, 本文利用地铁站内行人真实出站数据, 基于元胞自动机, 构建了行人疏散轨迹半仿真模型, 并利用实际流量数据优化该半仿真模型; 其次, 基于该轨迹模型, 为了满足高动态场景中的实时性, 采用复杂度较低的贪心选择策略分配最优疏散出口; 最后, 以杭州武林广场地铁站为例, 使用真实出站数据设计对比实验, 验证行人轨迹模型的有效性以及出口分配方法的性能. 结果表明, 本文所提出的行人轨迹模型能够较好的模拟行人的轨迹, 仿真中各出口疏散人数同真实出站数据拟合程度的可决系数R2达到了0.67. 相较于最短路径和最短时间出口分配方法, 本文所提出的方法在整体疏散效率上分别提高了27.2%和16.5%.     

A comparative study of evacuation strategies for people with disabilities in high-rise building evacuation

This paper presents new evacuation strategies for a heterogeneous population in high-rise building environments and compares them with traditional simultaneous evacuation strategy. To do so, we first define the maximum comfortable structural capacity of the building as the number of people that can be evacuated without heavy congestion, and estimate it based on flow rate and move frequency ratio. Then we present several evacuation strategies to efficiently evacuate heterogeneous residents at the maximum comfortable structural capacity. The simulation results for a 24-story building suggest several implications for emergency planners. First, we find that a vertically phased evacuation strategy that varies delay times by physical location, is not useful for the simulated building. Second, a phased evacuation strategy that applies a fixed evacuation delay to residents with wheelchairs reduces the aggregated evacuation times, but delaying evacuations of a specific group of individuals may not be ethical or accepted. Finally, evacuation strategies that allows residents with wheelchairs to use elevators are effective, suggesting that emergency administrators should assess whether elevators in their buildings are appropriate for evacuation purposes with appropriate electric controls, electric power, and fire and smoke protection.     

An agent-based simulation system for concert venue crowd evacuation modeling in the presence of a fire disaster

A key activity in emergency management is planning and preparation for disaster. If the right safety measures are implemented beforehand, harmful effects can be significantly mitigated. However, evaluation and selection of effective measures is difficult due to the numerous scenarios that exist in most emergency environments coupled with the high associated cost of testing such scenarios. An agent-based system employs a computational model of autonomous interacting agents in an environment with the purpose of assessing the emergent behavior of the group. This paper presents a prototype of a computer simulation and decision support system that uses agent-based modeling to simulate crowd evacuation in the presence of a fire disaster and provides for testing of multiple disaster scenarios at virtually no cost. The prototype is unique in the current literature as it is specifically designed to simulate a concert venue setting such as a stadium or auditorium and is highly configurable allowing for user definition of concert venues with any arrangement of seats, pathways, stages, exits, and people as well as the definition of multiple fires with fire and smoke dynamics included.