基于断裂点理论和网络加权Voronoi图分析的北京市商业中心辐射域研究

Radiation domain of commercial centers in Beijing based on breakpoint theory and analysis of road network weighted voronoi diagram

城市断裂点理论作为城市地理学经典理论,与Voronoi图结合将是划分城市商业中心空间势力范围的一种有效工具.尝试对北京市主要商业中心的辐射范围进行了划分,实现了基于道路网络分析的网络Voronoi图和网络加权Voronoi图的构建.对道路系统更新前后构建的网络Voronoi图比较分析,表明构建网络加权Voronoi图是模拟商业中心辐射域的一种有效方法.将断裂点理论与网络加权Voronoi面域图结合,模拟出北京市主城区道路系统更新前后商业中心不同的辐射域空间格局变化,并提取了辐射域覆盖面积、覆盖人口、路网长度、路网密度等信息.实验结果表明:网络加权Voronoi面域图在模拟商业中心辐射域时更加接近地理实际;道路系统更新升级对于商业中心辐射空间格局变化影响明显;商业中心自身规模影响其辐射域的扩张趋势.

To determine the spatial domain of influence of urban commercial centers, the transmission force of road network could not be ignored. The Breakpoint theory as a classical theory of Urban Geography, combined with Voronoi ters. It was diagram was an effective tool to divide spatial domain of the influence of urban commercial cen- attempted to divide the radiation domain of commercial centers in Beijing. Firstly, thet Network Voronoi diagram and Network weighted Voronoi diagram were set up based on road network analysis. Then, by contrast of Network Voronoi diagram in different road network system, the weighted Voronoi area diagram based on network analysis was proved to be most effective to simulate the radiation domain of commercial cen- ters. Secondly, breakpoint theory combined with Network weighted Voronoi area diagram, the spatial pattern change of radiation domain of commercial centers in Beijing was simulated, whether or not the road network system was updated. Finally, there were picked up the covering information of radiation domain, including ar-ea, population, length of road network, density of road network and so on. The experiments data and analysis showed that, the weighted Voronoi area diagram was a near-actual and effective method to simulate the radia- tion domain of commercial centers. The influence of road system updated for the spatial pattern change of radi- ation domain of commercial center was obvious and the scale merit of commercial center affected the trend of radiation domain expansion.