基于社会力模型的民用机场航站楼消防安全评价

针对以往单独进行火灾烟气蔓延模拟以及忽略疏散过程中人自身因素、人与人之间相互作用和环境对人的作用以评估航站楼消防安全的现状,基于国内某机场航站楼旅客进出港的过程,运用社会力模型模拟仿真航站楼内人员流动,同时采用火灾动力模拟软件FDS模型结合楼内设施模拟分析特定火灾背景下航站楼内火灾烟气蔓延,在此基础上,仿真模拟航站楼内人员疏散情况,分析不同火灾场景下航站楼的人员安全疏散时间、各个疏散通道疏散人数,进而研究安全出口宽度设置对于人员疏散时间的影响。与常用的安全评价方法进行对比分析,基于社会力模型和FDS模型的航站楼仿真安全评价方法考虑了旅客流动的分布特征和随机性,模拟更接近于真实的疏散场景。     

基于元胞自动机的应急疏散系统仿真研究

分析了紧急情况下人员疏散的难点,提出了应急系统人员疏散策略,设计了一种基于CA的人员疏散模型.通过模型仿真,分析模型中相关参数对疏散效果的影响,在此基础上对人员疏散模型中地场方法进行改进,模拟结果表明,基于CA的应急疏散仿真能够很好的模拟建筑内人员应急疏散行为及紧急事件的发展情况.同时该仿真方法具有直观性、灵活性和可扩展性,为应急管理研究提供了一个很好的研究思路.     

基于FDS的火灾仿真研究

研究火灾中人员优化疏散、减少损失问题,为获取各种火灾数据,克服实际火灾数据获取困难及体现疏散过程中人员的个体差异性,研究了在公共火灾中的疏散方法,并构建了具有个体差异性的人员疏散模型.研究了火灾仿真软件及基本控制方程.利用FDS( Fire Dynamics Simulator)火灾研究工具软件可较为准确快速地分析复杂的三维火灾问题.以某KTV场所为应用实例,研究FDS的具体应用方法.根据FDS火灾数据,在Java环境下实现了上述模型,并进行了相应的仿真验证.结果表明可为火灾研究和人员疏散提供手段,并对建筑物的布局设计具有一定的指导意义.     

船舶多出口房间疏散问题研究

为了提高船舶人员疏散效率,针对船舶火灾情况下多出口房间的人员疏散,提出了结合博弈论和社会力模型的疏散优化模型.模型考虑了人员之间的相互作用、人员到出口的距离和出口大小对人员选择出口的影响,用博弈理论得出多出口条件下人员个体的最优决策路线,并对社会力模型中人员动力学进行修正,作为新模型中人员运动的动力学基础.用新模型对多出口无障碍房间进行人员疏散仿真,结果显示,上述模型可以仿真出人员在多出口房间中对出口的优化选择,并能改善基础社会力模型中存在的不足.仿真结果表明,上述模型能有效缩短人员逃离房间的时间,并能模拟多出口条件下人员疏散的场景,为规划和管理多出口房间的疏散提供参考.     

基于物理的真实感火灾疏散仿真

人员的疏散是目前防火防灾研究的热点,但是传统的人员疏散研究多集中于人群疏散的离散仿真及可视化显示,无法逼真地表现个体的疏散行为.从火灾时人员疏散的物理特点出发,考虑不同人在火灾情况下的行为特征,采取几何连续的疏散空间,可较准确地计算人员安全疏散的时间及路径;建立了建筑物、火焰和角色动画的三维模型,动态交互地模拟火灾疏散过程,仿真效果逼真.     

基于人工势场和Agent的人员疏散系统仿真

从聚众场合火灾中疏散群体的个体角度出发,结合人工势场和Agent,提出了微观的仿真模型。该模型首先将场化影响人行为的火、门和障碍物等因素量化,构建了人工势场体系,其次以个体为对象,通过受力分析确定人员移动方向,最后通过是否开启安全通道,有无人员疏导的分析对比,合理仿真了人员疏散情形。基于Visual C++实现了疏散仿真系统,通过仿真结果分析,该系统能够较真实地模拟人员疏散过程。     

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。     

基于元胞自动机的人员疏散过程研究

紧急情况(如火灾等)下的人员疏散研究可为减少人员受到伤害提供必要的指导.提出了一种基于元胞自动机的微观离散模型,该模型将人群按照年龄和性别进行了划分,把所有人员都作为一种客体.在疏散过程中,每个人员的行为参照在其视野中的其它人员的行为进行加权处理.针对不同移动速度的人员比例,权系数等参数,进行了多方面的数值模拟,研究结果表明,提出的模型能够较好地模拟紧急情况下的人员疏散现象.     

森林场景可视化和林火模拟仿真技术研究综述

森林是生态环境系统的重要组成部分。随着气候变暖,恶劣气候气象条件造成全球森林火灾频繁发生,给国民经济和消防救援带来巨大挑战,森林火灾已成为全球主要的自然灾害。因此,森林场景可视化建模、3维场景仿真、林火模拟仿真、火场复现、预测和灾害评估成为林业虚拟仿真研究热点。本文对树木形态结构建模技术、森林场景大规模重建和实时渲染、森林场景可视化、林火模型和林火模拟仿真等前沿技术和算法进行综述。对相关的林木、植被的形态结构表达和真实感可视化建模方法进行归纳分类,并对不同可视化方法的算法优劣、复杂度、实时渲染效率和适用场景进行讨论。基于规则的林木建模方法和基于林分特征的真实场景重建方法对大规模森林场景重建技术进行分类,基于物理模型、经验模型和半经验模型对森林火灾的林火模型、单木林火、多木林火模拟和蔓延进行总结,对影响林火蔓延的不同环境气象因子（如地形地貌、湿度、可燃物等）和森林分布对林火发生、扩散和蔓延的影响进行分析,对不同算法的优劣进行对比、分析和讨论,对森林场景可视化和林火模拟仿真技术未来的发展方向、存在问题和挑战进行展望。本文为基于森林真实场景的森林火灾模拟仿真和数字孪生沉浸式互动模拟系统的构建提供了理论方法基础,该平台可以实现森林场景快速构建、不同火源林火模拟、火场蔓延模拟仿真以及不同气象影响条件的火场预测,可对森林火场救援指挥、火场灾害评估和火场复原提供可视化决策支持。     

森林火灾蔓延的三维实时仿真

本文着眼于林火行为的预测预报及林火蔓延模拟的三维动态可视化问题,探讨了森林火灾蔓延三维仿真思路,采用了一种适合林火的火焰和烟雾模拟生成方法.作者以福建省漳浦林业地区的实际情况为例,创建了三维林火蔓延模型,利用VEGA三维实时仿真平台,实现了火灾蔓延三维动态仿真.最后,本文就林火蔓延模型和蔓延模拟的发展前景做了简要探讨.     

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.     

基于数字地球的林火灾害建模

针对数字地球上林火灾害可视化问题,建立林火灾害仿真可视化框架。设计蔓延表现算法,采用Rothermel火行为计算模型和邻接单元蔓延模型。提出一种网格均匀划分的简化模型,进行仿真实验。结果表明,该方法能在数字地球上表达林火蔓延过程,较好地描述林火蔓延物理机理,为三维地理环境上的灾害分析提供辅助支持。     

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.     

Agent-based simulation of affordance-based human behaviors in emergency evacuation

Complex cognitive processes corresponding to human control behaviors cannot be easily inferred using (1) a logical rule-based model, (2) a statistical model, or (3) an analytical predictive model. Predicting human behaviors in complex and uncertain environments like emergency evacuation is considered almost impossible (at least NP hard) in systems theory. In this paper, we explore simulating human behaviors using affordance-based finite state automata (FSA) modeling, based on the ecological concept of affordance theory. To this end, we introduce the conceptual and generic framework of affordance-based human behavior simulation developed through our previous work. Following the generic framework, formal simulation models of affordance-based human behaviors are developed, especially for emergency evacuation, to mimic perception-based dynamic human actions interacting with emergent environmental changes, such as fire. A “warehouse fire evacuation” case is used to demonstrate the applicability of the proposed framework. The human action planning algorithms in the simulation model are developed and implemented using the Adjusted Floor Field Indicators, which represent not only the evacuee’s prior knowledge of the floor layout but the perceivable information about dynamic environmental changes. The results of our simulation study verify that the proposed framework accurately simulates human fire evacuation behavior. The proposed framework is expected to capture the natural manner in which humans behave in emergency evacuation and enhance the simulation fidelity of analyses and predictions of perceptual human behaviors/responses in the systems by incorporating cognitive intent into human behavior simulations.     

A household-level approach to staging wildfire evacuation warnings using trigger modeling

Wildfire evacuation trigger points are prominent geographic features (e.g., ridges, roads, and rivers) utilized in wildfire evacuation and suppression practices, such that when a fire crosses a feature, an evacuation is recommended for the communities or firefighters in the path of the fire. Recent studies of wildfire evacuation triggers have used Geographic Information Systems (GIS) and fire-spread modeling to calculate evacuation trigger buffers around a location or community that provide a specified amount of warning time. Wildfire evacuation trigger modeling has been applied in many scenarios including dynamic forecast weather conditions, community-level evacuation planning, pedestrian evacuation, and protecting firefighters. However, little research has been conducted on household-level trigger modeling. This work explores the potential uses of wildfire evacuation trigger modeling in issuing household-level staged evacuation warnings. The method consists of three steps: 1) calculating trigger buffers for each household; 2) modeling fire-spread to trigger the evacuation of all households; and 3) ranking households by their available (or lead) time, which enables emergency managers to develop a staged evacuation warning plan for these homes. A case study of Julian, California is used to test the method's potential and assess its advantages and disadvantages.     

Integrating fire spread patterns in fire modelling at landscape scale

Fire spread modelling in landscape fire succession models needs to improve to handle uncertainty under global change processes and the resulting impact on forest systems. Linking fire spread patterns to synoptic-scale weather situations are a promising approach to simulating fire spread without fine-grained weather data. Here we present MedSpread—a model that evaluates the weights of five landscape factors in fire spread performance. We readjusted the factor weights for convective, topography-driven and wind-driven fires (n = 123) and re-assessed each fire spread group's performance against seven other control simulations. Results show that for each of the three fire spread patterns, some landscape factors exert a higher influence on fire spread simulation than others. We also found strong evidence that separating fires by fire spread pattern improves model performances. This study shows a promising link between relevant fire weather information, fire spread and fire regime simulation under global change processes.     

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。     

计算机图形技术在林火蔓延模拟计算中的应用

蔓延模型在过火区图元集和蔓延灰度图的基础上进行位图操作和轮廓搜索,用蔓延填充处理地理要素的复杂拓扑关系,以位图旋转和错切代替过火区形状的投影变换,利用地形灰度图计算太阳辐射,由此克服了原有波动模型计算性能上的局限.对利用图形技术提高计算速度的实质作了理论分析.最后用算例证实了文中模型能提供精确、实时、可靠、全局、易维护、高适应性的火场发展图.