【摘要】 目的:探讨几类传染病的传播与流行规律。方法:利用微分方程理论建立传染病的数学模型并对模型进行动力学分析。结果:建立了传染病的几个数学模型,并获得了模型的一些动力学特征。结论:某些传染病存在区分传染病是否会流行的阈值。当有关参数值不超过该阈值时,传染病不会流行。当有关参数值大于该阈值时,传染病会流行。更多还原

【Abstract】 Objective:To investigate the spread regularities of several types of infectious diseases.Methods:The mathematical models of infectious diseases were established and performed the analysis on the dynamic characters of the models by means of the theory of differential equations.Results:Several mathematical models of infectious diseases were established and some dynamic characters of the models were obtained.Conclusion:For certain infectious diseases,there exists a threshold level which distinguishes whether the infectious diseases will spread.If the related parameter value does not exceed the threshold level,the infectious diseases will not spread;if the related parameter value is greater than the threshold level,the infectious disease will spread.更多还原