【作者】 周金旺；

【导师】 刘慕仁； 孔令江；

【作者基本信息】 广西师范大学 ， 系统理论， 2009， 硕士

【摘要】 随着社会的高速发展,城市规模急剧膨胀,城市人口迅速增长,大型高层建筑、商业繁华街、公共场所等大量涌现。在这些人员密集的场所,一旦发生火灾、地震、危险源泄漏等紧急情况,如何将建筑物中的大量人员快速安全地疏散是保证人员安全的重要手段,因此,对行人流安全运动的研究已经成为一件极为紧迫和相当重要的事情。行人流是由相互作用的行人构成的多主体复杂系统,行人彼此之间具有较强的非线性相互作用,因此,行人流的运动比交通车辆流的运动更加复杂。为了研究和描述行人的运动,人们提出了各种各样的行人流微观仿真模型,最主要的有社会力模型、格子气模型及元胞自动机模型等,其中元胞自动机模型因其易于计算机模拟运算,受到了更为广泛的关注。元胞自动机是一种时间、空间和变量均离散的数学模型,具有算法简单、灵活可调和计算效率高等特点,是研究非线性复杂系统的有效工具,具有广阔的应用前景。本文根据行人运动特征和建筑物结构的不同特点,在目前对行人流研究的基础上,对现有的某些模型存在不足的地方加以改进使其更加完善。用改进的模型或创新的方法建立新的模型,计算机模拟了特定场合(情景)下行人的安全运动与疏散过程,讨论了不同参数对行人运动的影响,并研究了行人运动自组织现象及其相变和时空图样特性。本文的主要工作包括以下四个方面:1.根据二维元胞自动机的Moore邻居并考虑房间的结构确定行人运动规则,建立行人流疏散仿真模型,对较大房间内人员疏散过程进行了模拟研究,该模型能够较好地再现了房间内人员疏散的整个过程,得到了行人在疏散过程中出现的典型现象,如拥挤、堵塞、人群的拱形结构等,并讨论了疏散时间与房间出口宽度、人员密度及与平均速度和平均流量之间的变化关系。2.考虑行人的位置交换、侧向前进和后退行为,建立了一种改进的元胞自动机模型,来研究地下通道中具有多种运动速度的双向行人流。并将改进的元胞自动机模型同Weng的模型相比较。计算机模拟表明,改进的模型具有提高系统中行人的平均速度并降低行人占据密度的倾向。3.熟悉的行人之间经常存在着聚集运动的整体跟随行为现象,为了研究成对行为对疏散过程的影响,考虑了行人的并排成对、前后成对和混合成对三种方式,建立了一个新的元胞自动机模型,研究了三种成对方式对双出口房间内行人疏散过程的影响,并分析、讨论了不同参数下成对方式之间的差异,得到了行人单个疏散总要比成对疏散快,行人成对行为总要对疏散起阻碍作用的特征,对于双出口的房间,两出口间距太小或太大也都不利于行人的疏散。4.根据内廊式建筑楼层系统的结构特点,重新定义位置危险度,并引入运动优先级的概念,对楼层中的行人分别采用同步并行更新和排队按序更新位置,建立楼层系统行人疏散元胞自动机模型,对内廊式建筑某楼层的行人疏散过程进行了模拟研究,得出了行人排队按序疏散能极大地缩短疏散时间提高疏散效率,房间出口相对位置对疏散时间影响较小,而房间出口宽度、走廊宽度对整个疏散有较大的影响。最后,对全文的工作进行了总结,并指出了若干有待进一步研究的问题,对今后行人流的研究进行展望。更多还原

【Abstract】 With the rapid development of society, rapid expansion of urban scale, the urban scale inflates suddenly, urban population explosive growth, large-scale high-rise construction, commercial lively street, public place and so on massive emergences. In these crowded place, Once has the emergency case, such as the fire or the earthquake and so on, how is guarantees building’s in massive people fast safety dispersal the personal security the important means that ,therefore, research of the security of pedestrian flow movement has become a very necessary and signification.Pedestrian flow is a kind of complex system with multi-agent, which has a strong nonlinear interaction between the pedestrian, therefore, the movement of pedestrian is more complex than the traffic flow. In order to research and describe the movements of the pedestrian flow, many micro-simulation models have been proposed by people, these include the more important model such as social force model, lattice gas model and cellular automaton model. The research of cellular automata model has been concerned extensively because of its easy computer simulation. Cellular automaton model is a mathematical model in which space, time and state values are discrete. It’s parallel and simple for computation, with algorithm simple, flexible and adjustable and high computational efficiency, so cellular automaton is a very good tool for simulating variable complex nonlinear phenomena and physical problems.According to the characteristics of pedestrian movement and the structure of the different building, in this paper, we improved the current deficiencies of study on pedestrian flow to make it more perfect. Using the improved model or innovative methods to propose a new model, computer simulation of the specific occasions (the scene) under the pedestrian safety movement with the evacuation process, discussed the different parameters on the impact of pedestrian movement and studied the phenomenon of self-organizing pedestrian movement and phase transition and characteristics of spatial and temporal patterns.This dissertation consists of the following five main parts:1. According to two-dimensional Cellular automata Moore neighbors and Considering the structure of the room, pedestrian moving rules were established. Occupant evacuation process from a hall was simulated via cellular automaton model. The model can better reproduce the room evacuation of the entire process, the simulation results show that the presented model can capture some essential features of pedestrian counter flows, such as jamming, congestion, arching around the door et al. The relationships among escape time, exit width, mean velocity, mean flux and the density of pedestrian were obtained by simulation.2. Taking into account three basic pedestrian behaviors, position-exchange, lateral-move and step back, we proposed an improved cellular automaton model to simulated pedestrian counter flow with different velocities in subterranean channel. We compared cellular automaton model with Weng’s model. By using computer simulation, the improved model is more efficiency. Moreover, Pedestrians in the system tend to have higher mean velocity and lower occupancy density.3.Collective following behavior is a common phenomenon among familiar pedestrians, In order to investigate the effect of such behavior, a new cellular automaton evacuation model is proposed to simulate the evacuation process for two exits by considering the side-by-side paired, the front-behind paired, and the mixed paired. Three types of paired pattern are respectively discussed and analyzed in detail under different parameters. We get the following conclusions: paired behaviors hindered the evacuation. For a room have two exits, the distance between the two doors is too small or too large is also not conducive to pedestrian evacuation.4. Considering the structural features of building which composed of one corridor at central and several rooms, we redefined the position danger grade, and introduced the concept of movement priority, all the pedestrians in the system are synchronized update or updated in order respectively. Pedestrian moving rules and the evacuation model were established. By using computer simulation, pedestrian evacuated in order can greatly shorten the evacuation time and improve the efficiency of the evacuation, the location of the exit have a smaller impact on evocation time, while the exit width and the corridor with play a important role.Finally, we give the conclusions of our works and present the prospect of further research of pedestrian flow.更多还原