Improved integrated metric for quantitative assessment of resilience

Abstract

Resilience provides a new approach that system administrators can use in the design and analysis of engineering systems to enhance the ability of such systems to withstand uncertain threats. In this article, an improved integrated metric is proposed for the quantitative assessment of resilience. The proposed metric is constructed in the form of a summation of two capacities: absorptive and restorative capacities. A weight coefficient is assigned to each capacity to enhance the flexibility according to various system requirements of stakeholders. In addition, based on the absolute time scale, a new time factor is proposed and incorporated into the resilience metric to quantify the effect of time on system performance. To test the performance of the proposed metric, three experimental studies are conducted wherein the proposed metric is compared with two other metrics reported in the literature. The results indicate that the proposed metric extends the flexibility of the previous metrics to systems where the time scale is addressed, and that the numerical values of resilience lie in a proper range and can be compared conveniently across different engineering systems. Furthermore, an example of an information exchange network is adopted to demonstrate the applicability of the proposed metric.