基于复杂网络的社区供应保障韧性评估方法

An Evaluation Method of Community Supply Support and Resilience Based on Complex Network

特大城市生活必需品供应保障体系直接影响社区的供应韧性,而社区系统无法孤立存在,其作为城市治理基本单元对推动供需联动与增强城市韧性具有关键作用。本研究探索性提出一种基于复杂网络理论的城市社区供应保障韧性评估方法,尝试测度社区动态韧性,实现从“单系统评价”走向“多系统关联评价”的韧性评估底层理论思维突破。以广东省广州市中心城区六区为例,充分利用手机信令等多源数据,基于市民时空间行为构建“市场-社区”生活物资供需网络,同时基于社区韧性5个指标制定网络攻击策略;引入级联失效机制评估其网络抗毁性,结合熵权法赋予权重得到社区韧性评估结果;并通过研究供应网络不同阶段节点失效的社区影响因素,进一步解析社区韧性与供应体系间的影响机理。研究发现:①基于本研究构建的城市生活物资网络模型,可实现较好地模拟城市社区供需网络和评价社区韧性,其中潜在供应保障缺失的低韧性社区主要分为老旧街区、城中村、城郊街区3种空间类型;②通过针对社区5种不同攻击策略下网络抗毁性分析,发现社区韧性主导影响因素不同,其中人口密度为首要考虑因素;③社区韧性与供应保障间存在复杂双向影响,包括低韧性社区在面对城市突发事件时存在明显脆弱性,社区自组织能力、供应设施布局与供应点间联动调度等都会影响社区整体韧性。

The assurance of a consistent supply of daily necessities in megacities is pivotal in fortifying community supply resilience.It is axiomatic that a community system is not an insular entity;rather,it intricately intertwines with various elements of urban systems.As a foundational unit of urban governance,the urban community is instrumental in facilitating a congruent nexus between supply and demand,thereby augmenting urban resilience.This study proposes an exploratory evaluation method for the urban community supply support and resilience based on complex network theory,attempting to achieve a breakthrough in the underlying theoretical framework of resilience assessment from"single system assessment"to"multi-system correlation assessment".Taking the six districts in the central city of Guangzhou as an example,we build a supply-demand network based on citizens'spatio-temporal behaviors using multi-source data such as mobile phone signaling data and other data.The attacking strategies of network are based on five community resilience indicators.Besides,the cascade failure mechanism is introduced to evaluate the network resilience,and the entropy-weighted method is employed to obtain resilience evaluation results.The influence mechanism of community resilience on the supply system is further analyzed by studying the factors affecting community node failure at different stages of supply network.The findings are as follows:(1)The proposed evaluation model of the community supply support and resilience can effectively simulate urban community supply-demand networks and evaluate the resilience of communities.Low-resilience communities are mainly categorized into three spatial types:old blocks,urban villages,and suburban blocks;(2)Through the analysis of network resilience under five different attack strategies,it is found that the dominant influencing factors are different,with the population density being the primary factor;(3)There exists a complex bidirectional relationship between community resilience and supply security,including the obvious vulnerability of low-resilience communities.And the community selforganization ability,the supply facility layout,and the linkage scheduling between supply points all affect the overall community resilience.