摘要
自然灾害实际上是“人-自然系统”呈现为一种无序的状态.在人类面临的众多的自然灾害中,有一些特殊类型的自然灾害具有“混沌性态”的无序性.当(1)人-自然系统内出现混沌无序并超过某一临界值时,或(2)人-自然系统的某一纯粹的自然子系统出现混沌无序性且继而引发了整个人-自然系统的无序性时,危及人类生存,便产生了自然灾害。在人-自然系统中,导致混沌性自然灾害的条件至少有四种:(1)三个或三个以上作用源加上非线性关系;(2)某些变量的周期性解变得不稳定;(3)控制参量超过临界值导致周期倍增;(4)周期性扰动作用于非线性项.在此基础上,本文进一步提出了防灾或减灾的如下四条原则措施:在人—自然系统中,(1)减弱某些非线性机制;(2)隔离某些相互作用的要素及其子环路;(3)控制某些关键性参量的变化,(4)提高(或降低)某些重要变量的临界值.
Some particular natural disasters possess the chaotic mechanisms.It is possible to appear these nat-ural disasters,if in the human-nature system (1) there are three interaction sources and some nonlinearrelation;or (2) the periodic solution of some variables becomes unstable;or (3)some periodic perturba-tions act the nonlinear relation;or (4) period doubling is formed by some control parameter surpassingthe critical point.So we can propose some principles of decreasing or preventing natural disasters as fol-lows:in the human-nature system,we must (1) reduce some nonlinear mechanisms;(2)separatethe interaction subsystems;(3) control the change of some key parameters;(4) raise (or reduce) thevalue of the critical point of the important variables.
出处
《自然灾害学报》
CSCD
1992年第2期3-16,共14页
Journal of Natural Disasters
关键词
自然灾害
混沌机制
非周期性
防治
Human-nature System
Natural disaster
Chaotic mechanism
Nonperiodic
Disaster Prevention and mitigation
