本文根据林火蔓延的自身特点结合元胞自动机(CA)分析,并提炼出影响森林火灾蔓延的关键影响因素。这一模型中森林用一个二维网格来表示,其中每个格点代表一棵树或代表空地,各节点的树具有相同的生长概率和着火概率,以一定的规则进行演化。这一模型忽略树木间的差别,假设初始状态只有一个着火点,不存在闪电袭击导致着火,从这一个着火点开始蔓延,如果绿树最近邻居中有一个树在燃烧,则它变成正在燃烧的树。通过这样的模型,研究蔓延的概率达到多大时森林可能会被烧光。
随着目前CA研究的深入,CA在森林火灾扩散的预测研究中越来越广泛,论文结合提出的模型,并根据CA表现出的很强的模拟复杂系统的能力,采用Matlab平台,做了模拟仿真的实验工作。采用动态方式进行模拟,使用图形页面展示,并可以根据仿真显示结果调整更新相关参数,最终得到一个能更好的模拟现实森林火灾蔓延情况的预测模型。最终,通过对显示结果的对比分析,验证了模型的可靠性及可用性。
关键词:森林火灾;元胞自动机(CA);蔓延;生长概率;着火概率
According to the characteristics of forest fire spread and cellular automata (CA) analysis, the key influencing factors of forest fire spread were extracted in this paper. In this model, the forest is represented by a two-dimensional grid, in which each lattice represents a tree or an open space, and the tree of each node has the same growth and ignition probability, which evolves according to certain rules. This model ignores the differences between trees, assuming that there is only one ignition point in the initial state and that there is no lightning strike that causes a fire, spreading from this point of ignition, if one of the nearest neighbors of the green tree is burning. Then it becomes a burning tree. With this model, When the probability of spreading is great, the forest may burn up.
With the development of CA research, it is more and more widely used in the prediction of forest fire diffusion. This paper combines the proposed model and adopts Matlab platform according to the ability of CA to simulate complex system. The experimental work of simulation is done. The simulation is carried out in a dynamic way, the graphical page is displayed, and the relevant parameters can be adjusted and updated according to the simulation results. Finally, a better prediction model for simulating the real forest fire spread is obtained. Finally, the reliability and availability of the model are verified by comparing and analyzing the display results.
Key words: forest fire; cellular automaton (CA); spread; growth probability; ignition probability
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