Improving resilience through vulnerability assessment and management

The increasing complexity of infrastructure systems and the possibility of severe consequences due to interdependency and uncertain demands have led to an increased emphasis on resilience. Resilience, in simple terms, is the ability of a system to withstand adverse conditions and to recover quickly from these. Its interpretations and linkages to the related concepts of vulnerability and risk are examined. It is argued that vulnerability is an inherent characteristic of any system, hard or soft, and its identification and management is essential for improving the system's resilience. A systems approach to identify the vulnerable failure scenarios uses the concepts of form, connectivity and hierarchical modelling. Modelling of interactions with social systems and assessing their consequences requires dealing with uncertainty and it remains a challenge.