# Transportation and Reserve of Emergency Medical Supplies during Public Health Events
## 4 Experimental Results
### Parameter Fitting of the SEIRD Model  
In this paper, the unit time is set as day (d). To solve the differential equations, it is necessary to estimate the parameters of the equations. To calculate the development trend of modern public health issues, according to the COVID-19 epidemic report issued by the China Health and Health Commission and the Hubei Health and Health Commission of China, the COVID-19 epidemic data released from 11 January 2020 to 11 April 2020 in the initial stage of the epidemic are used as fitting data, including confirmed data, lurker data, cured data, and death data [42]. It is necessary to preprocess the data before fitting the parameters. In the early stage of the epidemic, the monitoring reagent resources are scarce, the medical staff are insufficient, and the people are not familiar with the illness. Panic occurs easily, leading to hiding the actual number of infected people [43], and large fluctuations in the statistical data in Hubei. On 27 January 2020, due to the strengthening of detection capabilities, cases that had not been detected before turned into new cases, and there were more newly confirmed cases. Cases were allocated to the first 5 days in proportion. [PERSON], director of the National Public Health Center of the Ministry of Health of Kazakhstan, was interviewed by reporters on 8 May 2020 and commented on the recent prevention and control of the COVID-19 epidemic in China. According to [PERSON], the average treatment cycle of confirmed patients in China is 16-17 days. On 12 February 2020, \"clinical diagnosis\" was added to the classification of case diagnosis in Hubei Province, so that patients can receive standardized treatment according to confirmed cases as early as possible. The number of clinically diagnosed cases was included in the number of confirmed cases, infected but undetected patients and suspected cases were found as much as possible. A total of 13,332 clinically diagnosed confirmed cases were added, and the cases were assigned to the first 16 days in proportion, to preprocess the data and make it more scientific and convenient to study. According to the relevant literature, the latency time is designed [44] and adjusted according to the actual situation. The parameters values determined are shown in Table 4.  
According to the initial data on the COVID-19 epidemic released by the China Health and Health Commission and the CDC, using the epidemic data released on 11 January 2020, as input, the coefficients \(\beta\), \(\gamma\), and \(\mu\) of the differential equations are fitted by MATLAB using the least-squares method, and the differential equations are fitted by fourth-order Runge-Kutta. The results of the coefficient fitting are shown in Table 5, and the simulation diagram is shown in Figure 2.  
According to the results of the fitting in Figure 2, it can be seen that the number of susceptible persons fitted by the SEIRD model will gradually decrease, while the number of the exposed will first decrease and then increase. And the number of patients will produce a peak, while the number of recovered persons and dead persons will always increase. The majority of individuals will initially become patients, subsequently recover, and only a small minority are likely to die, owing to China's effective medical treatment and appropriate policies. The predicted results are consistent with the actual data, and the fitting effect is very consistent with the development of the epidemic situation. According to the China CDC report, as of December 20, 2022, 82.4% of people have suffered from COVID-19 and more than 82% of the population has been infected in two months. Most people will experience a 4-7-day cycle of illness, the virus toxicity will weaken, and most people will recover slowly.