Research On Emergency Medical Service Facilities Location For Serious Epidemic Diseases

Epidemics have a huge threat to human health and development.When a region is affected by a major infectious disease,it will not only cause a large number of human casualties and economic losses,but also cause psychological damage to people.So,how to quickly deploy emergency medical facilities to meet the massive medical needs after the epidemic is crucial.The location of emergency medical facilities are influenced the needs of each infected area and the number of medical resources(such as medical staff,hospital capacity,etc.).It also is closely related to the psychological status of patients.This paper focuses on the epidemics,especially large-scale infectious disease.First expounding the value of medical facilities network optimization,and then on the basis of considering the dynamic changes of the random demand and set up dynamic facility location model hierarchy.Finally,consider the psychological status of patients.A dualobjective optimization model was established to minimize the physical and psychological costs of medical facilities.The main contents of this paper include:(1)Forecast of medical demand under epidemic emergency.The reality is that there are clusters of deaths due to complications caused by the virus and asymptomatic clusters of infection among latent populations.Therefore,the population in the epidemic area is divided into six categories: susceptible,latent,infected,recovered,asymptomatic infected,and dead.Based on the COVID-19 epidemic spread characteristics from 2019 to 2020 and the classic SEIR infectious dynamics model,a modified SEIR model was established to obtain the time series data of the number of patients in each infected area.(2)Considering the dynamic level facility location under uncertain demand.Consider the network location of emergency medical facilities and the allocation of patients in an environment of uncertain demand.Epidemics usually last for a period of time.So,policymakers should not only consider the demand for medical resources in a single phase,but also consider the demand dynamics in the context of the continuous spread of infectious diseases and the increasing number of patients.In epidemic prevention and control,patients with different degrees of infection have different demands on medical services.According to the severity of infection,they can be divided into mild and severe patients.Emergency medical facilities can carry out prevention and control isolation and hierarchical diagnosis and treatment for mild and severe patients,and assign mild patients to general medical facilities and severe patients to advanced medical facilities.Therefore,according to the characteristics of infectious diseases,this paper establishes a dynamic level facility site selection model.The site selection results of each time stage are affected by patient allocation in previous stages and random demand,which is based on changes over time.Finally,genetic algorithm is used to compare and analyze the experiments under different hospital capacity scenarios,so as to further understand its value in management practice.(3)Dynamic level facility location considering psychological cost.The shortage of medical resources will affect the delayed admission of patients,which will bring psychological pressure to patients.Therefore,the psychological cost of patients should be considered as well as the physical cost of medical facilities.Considering the psychological conditions of patients and medical staff comprehensively,the psychological cost function was constructed,and the dual-objective dynamic hierarchical location model with the minimum psychological cost and total cost was established.The NSGA-II algorithm was used to solve the model,and finally the deployment plan of medical facilities at all levels in each period and the patient allocation plan were obtained.