The failure of a small but variable set of links can bring down a supply network Cascading behaviors are ubiquitous, from power-grid failures (1) to “flash crashes” in financial markets (2, 3) to the spread of political movements such as the “Arab Spring” (4). The causes of these cascades are varied with many unknowns, which make them extremely difficult to predict or contain. Particularly challenging are cascading failures that arise from the reorganization of flows on a network, such as in electric power grids, supply chains, and transportation networks. Here, the network edges (or “links”) have some fixed capacity, and we see that some small disturbances easily dampen out, but other seemingly similar ones lead to massive failures. On page 886 of this issue, Yang et al. (5) establish that a small “vulnerable set” of components in the power grid is implicated in large-scale outages. Although the exact elements in this set vary with operating conditions, they reveal intriguing correlations with network structure.

中文翻译：

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减少级联故障

一组小但可变的链接的故障可能会导致供应网络瘫痪 级联行为无处不在，从电网故障 (1) 到金融市场的“闪电崩盘”(2, 3) 再到政治运动的蔓延，例如“阿拉伯之春”（4）。这些级联的原因各不相同，有许多未知数，这使得它们极难预测或控制。特别具有挑战性的是由网络上的流量重组引起的级联故障，例如在电网、供应链和运输网络中。在这里，网络边缘（或“链接”）有一些固定的容量，我们看到一些小干扰很容易被抑制，但其他看似相似的干扰会导致大规模故障。在本期第 886 页，Yang 等人。(5) 确定电网中一小部分“易受攻击的”组件与大规模停电有关。尽管该集合中的确切元素因操作条件而异，但它们揭示了与网络结构的有趣相关性。