Speaker

Dr. Sooyhun Yang (Seoul National University) will give a seminar in which she analyses urban infrastructure networks and their similarities with natural systems regarding the emergent scaling features found in the traits of living organisms, especially those of natural river networks. A summary of her talk is copied below.

Abstract

Earth’s natural systems exhibit strikingly similar patterns across a broad range of observational scales. This is evident in the shapes of coastlines and river networks formed by geological and geomorphological processes. Similarly, biological systems hold a remarkable consistency in the number of heartbeats per lifetime of different animal species. These phenomena are scientifically termed as ‘scaling feature’, ‘scale invariance’, or ‘fractality’, and are mathematically represented as exponential or power-law functions. Interestingly, such scaling features have been found in diverse human-formed systems including cities and urban infrastructure networks over various sizes and types. For example, power-law relationships were observed in the node-degree distributions for dual-mapped graphs of urban drainage, water distribution, and road networks across numerous global cities. Furthermore, spatial interdependence and co-evolution of these networks over several decades were evidenced by the convergence of their functional topology, suggesting similar generative mechanisms in the human-built networks. Particularly for urban drainage networks, a pronounced scale invariance mirroring their expansion was identified. The finding was uncovered through core scaling expressions found from river networks which correspond to their natural counterparts. This presentation aims to introduce the emergence of scale invariant characteristics in the urban infrastructure networks, primarily based on pivotal studies conducted by the lecturer and her collaborative researchers. The talk will conclude with a discussion on how these research findings can inform the design and functionality of urban infrastructure networks to enhance their resilience against external and internal threats.