School of Aerospace Transport and Manufacturing, Cranfield University, Bedford, United Kingdom.
The Alan Turing Institute, London, United Kingdom.
Sci Rep. 2020 Feb 27;10(1):3599. doi: 10.1038/s41598-020-60501-9.
In an increasingly connected world, the resilience of networked dynamical systems is important in the fields of ecology, economics, critical infrastructures, and organizational behaviour. Whilst we understand small-scale resilience well, our understanding of large-scale networked resilience is limited. Recent research in predicting the effective network-level resilience pattern has advanced our understanding of the coupling relationship between topology and dynamics. However, a method to estimate the resilience of an individual node within an arbitrarily large complex network governed by non-linear dynamics is still lacking. Here, we develop a sequential mean-field approach and show that after 1-3 steps of estimation, the node-level resilience function can be represented with up to 98% accuracy. This new understanding compresses the higher dimensional relationship into a one-dimensional dynamic for tractable understanding, mapping the relationship between local dynamics and the statistical properties of network topology. By applying this framework to case studies in ecology and biology, we are able to not only understand the general resilience pattern of the network, but also identify the nodes at the greatest risk of failure and predict the impact of perturbations. These findings not only shed new light on the causes of resilience loss from cascade effects in networked systems, but the identification capability could also be used to prioritize protection, quantify risk, and inform the design of new system architectures.
在一个日益互联的世界中,网络动态系统的弹性在生态学、经济学、关键基础设施和组织行为学等领域都很重要。虽然我们很好地理解了小规模的弹性,但对大规模网络弹性的理解却很有限。最近在预测有效网络级弹性模式方面的研究,提高了我们对拓扑结构和动力学之间耦合关系的理解。然而,对于由非线性动力学控制的任意大规模复杂网络中单个节点的弹性的估计方法仍然缺乏。在这里,我们开发了一种顺序平均场方法,并表明在 1-3 步的估计之后,节点级别的弹性函数可以用高达 98%的精度来表示。这种新的理解将更高维度的关系压缩成一个一维的动态,以便于理解,映射了局部动力学和网络拓扑统计性质之间的关系。通过将这个框架应用到生态学和生物学中的案例研究,我们不仅能够理解网络的一般弹性模式,还能够识别出最容易发生故障的节点,并预测扰动的影响。这些发现不仅为网络系统中级联效应导致的弹性丧失的原因提供了新的认识,而且识别能力还可以用于优先保护、量化风险,并为新系统架构的设计提供信息。