菌痢流行过程的混沌特性研究及定量判据

Research into Chaotic Characteristics and Quantitative Criterion of Bacillary Dysentery Epidemic

以辽宁省本溪市１９５５～１９９６年的菌痢逐月发病的数据（Ｘｔ）为根据，利用混沌动力学中的“相空间技术”，给出Ｘｔ时间趋势图、混沌相图和递次振幅图，发现Ｘｔ遵从混沌特性及分布模型：Ｘｔ＋１＝０００２６５６１ｒ（Ｘｔ＋１２７９７２２）２ｅｘｐ｛－０００００２２１（Ｘｔ－２５５９４４４）２｝，求出菌痢流行涨落“阈值”ｒ∞＝０９８１４２６·式中，ｔ为发病月份，ｒ为菌痢流行的涨落度·

On the basis of the monthly reported cases of bacillary dysentery in Benxi city in the periods 1955～1996, the reconstruction technique of phase space of chaotic dynamics was employed. They gave the time series,the phase portrait and Poincare section, and found a new model X t+1 =0 0026561r(X t+127 9722) 2 exp {-0 0000221(X t-255 9444) 2}. Also they determimed a criterion to control the infective rate of the epidemic r ∞=0 981426 . In model t is month of cases of bacillary dysetery and r is the infective rate of epidemic.