大城市多中心静态结构和动态关联特征分析

以郑州市为例，基于居民依赖度和要素属性值对POI要素热点分析结果进行空间加权叠加，分析城市多中心空间静态结构；运用词向量和数据场理论，在表达居民出行偏好的基础上，利用轨迹数据分析城市多中心对动态目标的吸引强度，并挖掘多中心网络的动态交互关系。研究表明：① 城市静态要素呈中央集中、外围分散的圈层空间分布形态，部分多中心已形成了一定吸引聚集能力，而另一部分虽然规划前景广阔，但还远未形成副中心应有的分散疏解作用；② 城市多中心对动态目标的吸引强度不均衡，出租车和电动车轨迹显示的多中心吸引强度和空间交互关系虽有差异，但均体现出城市为典型的外溢型结构，核心城区仍然是空间交互的主要方向。因此，还需通过政策导向和基础设施建设等手段，增强外围多中心的吸引聚集能力，实现城市空间均衡发展。

Static Structure and Dynamic Correlation Characteristics of Polycentric Structure in Big City

Taking Zhengzhou as an example, the hot spot analysis results of POI elements are analyzed by spatial weighted overlay method based on the residents’ dependence and element attribute values, and the results show the static structure of urban polycentric space. This paper expresses residents’ travel preferences by using the theory of word vector and data field, analyzes the attraction strength of urban sub-centers to dynamic targets by using trajectory data, and explores the dynamic interaction relationships of polycentric networks. The results show that: 1) The static elements of the city are in a circle spatial distribution form with a centralized core and scattered peripheries. The density of various elements gradually decreases towards the periphery with Erqi Square as the center. On one hand, affected by the construction policies and plans of new urban districts, some sub-centers have formed the ability of attracting and gathering. Their functional positioning, industrial planning and surrounding traffic play an important role in regional development. On the other hand, although the planning prospects of some remote sub-centers are broad, they are far from forming the decentralization effect that the sub-centers should have. 2) The attraction strength of sub-centers to dynamic targets is not balanced. Although the polycentric attraction strength and spatial interaction shown by the trajectory of taxis and electric bicycles are different, they all reflect the typical overflow structure of this city. Various urban elements and populations gradually disperse from the overly dense core urban area to the periphery. The core urban area is still the main direction of spatial interaction. Therefore, it is necessary to create a good environment for the development of polycentric regions through policy guidance, strengthen the infrastructure and transportation facilities construction of characteristic functional centers, enhance the attraction of peripheral sub-centers, and achieve balanced development of urban space.