The aim of the present paper is to state a simplified nonlinear mathematical model to describe the dynamics of the novel coronavirus (COVID-19). The design of the mathematical model is described in terms of four categories susceptible ([Formula: see text], infected ([Formula: see text], treatment ([Formula: see text] and recovered ([Formula: see text], i.e. SITR model with fractals parameters. These days there are big controversy on if is needed to apply confinement measure to the population of the word or if the infection must develop a natural stabilization sharing with it our normal life (like USA or Brazil administrations claim). The aim of our study is to present different scenarios where we draw the evolution of the model in four different cases depending on the contact rate between people. We show that if no confinement rules are applied the stabilization of the infection arrives around 300 days affecting a huge number of population. On the contrary with a contact rate small, due to confinement and social distancing rules, the stabilization of the infection is reached earlier.

中文翻译：

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基于新型冠状病毒 (COVID-19) 动力学的非线性 SITR 分形模型设计

本文的目的是陈述一个简化的非线性数学模型来描述新型冠状病毒 (COVID-19) 的动态。数学模型的设计从易感（[公式：见文]、感染（[公式：见文]）、治疗（[公式：见文]和恢复（[公式：见文]）四个类别来描述，即具有分形参数的 SITR 模型。如今，关于是否需要对这个词的人群采取限制措施，或者感染是否必须发展出与我们的正常生活共享的自然稳定性（如美国或巴西政府声称），存在很大争议。我们研究的目的是呈现不同的场景，根据人们之间的接触率，我们在四种不同的情况下绘制模型的演变。我们表明，如果不应用限制规则，感染的稳定会在 300 天左右到达，影响大量人口。相反，由于限制和社会疏远规则，接触率很小，感染的稳定会更早达到。