Ershkov Sergey V, Rachinskaya Alla
Plekhanov Russian University of Economics, Scopus Number 60030998, 36 Stremyanny Lane, Moscow, Russia 117997.
Odessa I. I. Mechnikov National University, 2 Dvoryanskaya St, Odessa, Ukraine.
Nonlinear Dyn. 2021;106(2):1433-1452. doi: 10.1007/s11071-021-06244-2. Epub 2021 Feb 14.
We have presented in the current analytic research the generating formulae and results of direct mathematical modelling of non-classical trends for COVID-19's evolution in world which, nevertheless, can be divided into two types: (1) the general trends for European countries such as Germany presented by the curve of with up-inclination of the upper limit of saturation (at the end of first wave of pandemic) as well as for other cases of key countries that suffered from pandemic such as USA, India, Brazil, Russia (we conclude that the same type of coronavirus pandemic is valid for most of the countries in world with similar scenarios of the same type for general trends); (2) non-classical general trends for Middle East countries (such as Iran), with the appropriate bulge on graphical plots at the beginning of first wave of pandemic. We expect that the second wave of pandemic will pass its peak at the end of December 2020 for various countries. Moreover, the second wave of pandemic will have come to end at first decade of January 2021 in Germany and Iran (but at the end of January 2021 in India as well), so we should restrict ourselves in modelling the first and second waves of pandemic within this time period for these countries. Thus, the model of first approximation is considered here which allows to understand the mean-time trends of COVID-19 evolution for the first + second waves of pandemic for USA, Brazil and Russia, or predict the approximated time period of the upcoming third wave of pandemic in cases of India, Germany and Iran.
在当前的分析研究中，我们展示了对全球新冠疫情演变非经典趋势进行直接数学建模的生成公式和结果，不过这些趋势可分为两类：（1）欧洲国家（如德国）的总体趋势，由饱和上限呈上升趋势的曲线表示（在疫情第一波结束时），以及其他遭受疫情的主要国家（如美国、印度、巴西、俄罗斯）的情况（我们得出结论，对于世界上大多数国家而言，相同类型的新冠疫情在总体趋势上具有相似情景）；（2）中东国家（如伊朗）的非经典总体趋势，在疫情第一波开始时，图表上有相应的凸起。我们预计，2020年12月底，各国的疫情第二波将达到峰值。此外，德国和伊朗的疫情第二波将于2021年1月的第一个十年结束（印度也将于2021年1月底结束），因此对于这些国家，我们应将疫情第一波和第二波的建模限制在这一时间段内。因此，这里考虑了一阶近似模型，它可以帮助理解美国、巴西和俄罗斯疫情第一波 + 第二波期间新冠疫情演变的平均时间趋势，或者预测印度、德国和伊朗即将到来的疫情第三波的近似时间段。
