GIS与Voronoi多边形在医疗服务设施地理可达性分析中的应用

GIS and Voronoi Polygon Based Public Health Care Accessibility Analysis

地理可达性是研究评价各种服务设施布局及其服务域的重要指标之一,空间距离、交通便捷性、出行成本等是可达性测度的重要因子。由于医疗设施等公共设施通常以服务的公平性和覆盖性为目标,因此可定义居民点到最邻近医院的距离为地理可达性的测度。在此基础上,作者提出了基于GIS与Voronoi多边形的地理可达性计算方法。这一方法不仅将地理可达性分析中的空间点对之间的距离计算简化为空间查询,方便了GIS应用,而且计算的Voronoi多边形在本质上就是最邻近意义上医院的服务域,即服务域内各居民点到该医院的距离就是最邻近距离。此外结合人口分布等属性数据,还可深入分析各医院的服务承载力,本方法为医疗设施等公共服务设施的规划决策提供了重要的工具。

Accessibility is an important concept and approach to describe the geographic location of the health care service in relations to population need. Geographic accessibility is often measured by some spatial related factors like distance, transportation, travel time, and cost. Because the equity and converging is the main objects of public health care, the author defines the nearest distance between the location of hospital and residential area, which is represent by the centroid of the residential polygon. And then we proposed a GIS and Voronoi based approach to measure the geographic accessibility. According the distribution of hospitals, the Voronoi polygons was computed in MapInfo, which is the hospital service area defined by the nearest distance from residential area to that hospital. We found that , the GIS based Voronoi polygon method not only avoid complex computation in accessibility measure, but also reveal more useful information by visualize the service area and the distribution of nearest distance. The analysis approach of GIS based Voronoi polygon to accessibility measure also suit for other public service facility like health care.