城市群复合交通网络级联抗毁性

Invulnerability of Urban Agglomeration Compound Traffic Network against Cascading Failure

为保障城市群交通运输系统运营安全,解决城市群交通运输系统站点或线路故障引起的交通网络瘫痪问题,以"复合"的视角对网络级联抗毁性进行深入研究。针对不同运输方式交通网络节点、连边的差异性,构建基于强度和运输方式分担率的城市群复合交通网络模型,进行网络级联失效分析。考虑节点暂停状态对网络性能的影响,分析节点受损后的负载重分配,构建城市群复合交通网络级联失效模型,并引入基于观测信息模糊度的不完全信息攻击策略,以修正后的测度指标评估级联失效对网络抗毁性造成的影响。以呼包鄂城市群为例进行仿真试验,发现轨道子网的叠加增大了节点的过载承受能力,将大量失效节点转变为暂停节点。同时,容量参数、过载能力调节参数越大网络的级联抗毁性越强,而观测信息模糊度越大,网络级联抗毁性不一定越强,其产生作用的阈值为0.4。结果表明:复合交通网络的构建提高了单一运输方式交通子网的级联抗毁性。城市群交通子网的叠加可以增大节点的过载承受能力,将大量失效节点转变为暂停节点,通过增大节点容量并提高其过载承受能力,能够防止级联失效对复合交通网络产生的不利影响。通过对识别出的关键节点加强防护可以进一步优化复合交通网络的级联抗毁性。

In order to ensure the security operations of urban agglomeration transport system and solve traffic network failure caused by urban agglomeration transport system station or line fault, the invulnerability against cascading failure is researched in a ＂compound＂ perspective. In view of the different nodes and edges of traffic networks in various transport modes, the urban agglomeration＇s compound traffic network model based on strength and transport mode＇s share ratio is constructed for analyzing traffic network cascading failure. Considering the influence of node suspension state on network performance, the traffic load reassignment after node damage is analyzed, a cascading failure model of the compound traffic network is built. An incomplete information attack strategy considering the observation information fuzzy degree is introduced, and the impact of cascading failure on the network invulnerability is evaluated by the revised measure index. The simulation test is conducted taking Huhhot - Baotou - Ordos urban agglomeration for example, it is found that the superposition of rail sub-network increased the overload capacity of nodes, and large number of failure nodes is transformed into suspended nodes. The greater the capacity parameter and overload capacity adjustment parameter, the stronger of network invulnerability against cascading failure, but the greater of fuzzy degree of observation information, the not necessarily greater the invulnerability, its threshold value is 0.4. The result shows that （ 1 ） the construction of complex traffic network improved the invulnerability of rail sub-network under single transport mode against cascading failure; （2） the superposition of urban agglomeration transport sub-network can improve nodes＇ endurance capacity of overload and change large number of failure nodes into suspended nodes, improve node capacity and endurance capacity of overload can prevent the adverse effect to compound traffic network caused by cascading failure ; （3） strengthen the protection of the identified key nodes can optimize the invulnerability of compound traffic network in urban agglomeration.