Medical Facility Accessibility Analysis Based On Improved 2SFCA Algorithm And Layout Optimization

Medical service facilities usually adopt centralized and large-scale configuration to improve the utilization rate of medical resources,but often reduce the accessibility of remote areas,resulting in insufficient supply of medical resources in such areas.In order to further optimize the allocation of medical resources,accurate and reliable accessibility analysis should be carried out based on the distribution of existing medical resources to provide data support for the rational layout and optimization of medical facilities and the improvement of the supply level of medical resources.In the accessibility analysis,it is very important to study the actual distance and time from the demand point to the supply point,search radius,distance weight and other factors.Two-step floating catchment area method is a commonly used accessibility analysis method at present.Its search radius usually adopts the Euclidean distance between the demand point and the supply point,without considering the road connectivity between the two and the actual traffic speed of the road,resulting in inaccurate search results and the problem of single search radius.In terms of distance weight,this method also fails to consider the equal opportunity of disadvantaged population in the research unit,resulting in low accessibility results.Therefore,an improved two-step mobile search method was proposed in this paper to improve the accessibility analysis results and to optimize the spatial layout of medical service facilities in the research area.The main research contents and achievements of this paper include:(1)The influence factors of real-time road condition are integrated into the 2SFCA.The API interface of Amap was used to obtain the actual passage time for residential areas to reach the hospital under the real-time road conditions in weekday driving mode,and the time of morning peak,morning,noon,afternoon,evening peak and evening was obtained,so as to solve the problem that the calculation time was only based on the speed of national road planning in the past.(2)The improvement of 2SFCA includes: choosing different time thresholds as search fields to solve the problem of different time thresholds and different accessibility results,and associating the accessibility analysis results with time thresholds;By calculating the weight value of the residential area and the weight value of the corresponding population grid,to solve the problem of access to medical care of the disadvantaged population;Gaussian attenuation function is introduced to calculate the weight value to solve the problem that residents' willingness to travel decreases with the increase of distance and time.(3)The mature calculation method of position allocation model is adopted,and the driving speed of different roads in different road conditions is set to solve the problem that the original model is not accurate in the unified setting of driving speed.Three kinds of impedance interrupts are set at the same time to solve the problem that single impedance interrupts in the original model cannot explain the different results of layout optimization of different impedance interrupts.According to the accessibility analysis results and GIS spatial analysis technology,the effective spatial layout optimization of medical service facilities in the research area was carried out.The results of this study show that,in terms of the analysis of medical access,the study area shows a circular outward diffusion,and the outward diffusion decreases in the center of each urban area.In terms of the optimization of the spatial layout of medical facilities,the research area needs to increase the number of four hospitals to meet the requirements of residents for medical treatment.At the same time,in terms of accessibility analysis method,this paper selects the community as the minimum research unit,integrates real-time road condition factors,selects different search thresholds,and adds the weight value of population grid and other improvements have practical significance.In the layout optimization method,the driving speed of different roads in different road conditions and the interruption of different impedance are set,which can effectively improve the results of the optimized layout.The improved 2SFCA and location allocation model,in the research of accessibility analysis and spatial layout optimization,can obtain the status quo of the existing medical service and health system and understand the configuration of the existing medical service facilities.