Bio-Inspired Human Network Design: A Multi-Currency Robustness Metric Inspired by Ecological Network Analysis

Abstract

The Ecological Network Analysis (ENA) metric ecological robustness quantifies the unique balance that biological food webs have between their pathway efficiency and redundancy, enabling them to maximize their robustness to system disturbances. This robustness is a potentially desirable quality for human systems to mimic. Modeling the interactions between actors in human networks as predator-prey type exchanges (of a medium or currency rather than caloric exchanges) enables an ENA analysis. ENA has been shown to be a useful tool in improving the design of human networks because it allows the characteristics of biological networks to be mimicked. The application of these metrics is, however, limited to networks with only one flow type. Human networks are composed of many different types of flow interactions and thus a biologically-inspired indicator of total system robustness must take into account all of these interactions. This work further develops the traditional ENA ecological robustness metric to accommodate various flows between actors in multi-currency human networks. Two novel methods for quantifying multi-currency flow network robustness are introduced. The mathematical formulation for these new metrics is presented. The water network for the Kalundborg Eco-Industrial Park (EIP) is used as a case study to determine the benefits of the proposed robustness metrics. The results obtained using the single-currency robustness and the two multi-currency robustness metrics are compared using the case study. Based on the analysis of the results obtained at the system level, as well as at the sub-levels, both multi-currency metrics showed the ability to predict systems characteristics for the multi-currency Kalundborg EIP. While both of these are promising, more research regarding these metrics is needed in order to develop an elegant and comprehensive total system robustness metric.