Development of an Input-Output Model Considering Simultaneous Effect of Risks in Infrastructure under Dynamic Conditions

Abstract

In this paper, a multi-objective model is proposed based on Haimes and Jiang's Input-Output model [1], which was developed to examine the impact of each infrastructure's risks on the performance other infrastructures in an interconnected system. Also, the simultaneous effect of risks on the model was investigated. Additionally, to reduce the harmful effects of risks, risk response strategies and associated costs were identified for each risk. The proposed model selects the best response strategies, which minimizes the inoperability of any infrastructure considering the limited budget. Thus, the comparison between the static input-output inoperability model (IIM) and dynamic inoperability input-output model (DIIM) was made for each infrastructure's risks and associated risk responses considering the simultaneous effect of risks. In the first case, 32 out of the 48 selected risk responses have been eliminated the effect of the relevant risk, whereas in the second case only 9 risk responses had this capability. Therefore, the simultaneous occurrence of risks leads to a decrease in the performance of the infrastructure as well as an increase in the inoperability of the infrastructure, and as a result, the efficiency of the responses decreases.