Reviewing qualitative research approaches in the context of critical infrastructure resilience

Modern societies are increasingly dependent on the proper functioning of critical infrastructures (CIs). CIs produce and distribute essential goods or services, as for power transmission systems, water treatment and distribution infrastructures, transportation systems, communication networks, nuclear power plants, and information technologies. Being resilient becomes a key property for CIs, which are constantly exposed to threats that can undermine safety, security, and business continuity. Nowadays, a variety of approaches exist in the context of CIs’ resilience research. This paper provides a state-of-the-art review on the approaches that have a complete qualitative dimension, or that can be used as entry points for semi-quantitative analyses. The study aims to uncover the usage of qualitative research methods through a systematic review based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The paper identifies four principal dimensions of resilience referred to CIs (i.e., techno-centric, organisational, community, and urban) and discusses the related qualitative methods. Besides many studies being focused on energy and transportation systems, the literature review allows to observe that interviews and questionnaires are most frequently used to gather qualitative data, besides a high percentage of mixed-method research. The article aims to provide a synthesis of literature on qualitative methods used for resilience research in the domain of CIs, detailing lessons learned from such approaches to shed lights on best practices and identify possible future research directions

FAILURE MODE EFFECTIVE ANALYSIS IN A BOILER USING COMBINATION OF EVENT TREE AND FAULT TREE ANALYSIS

Boilers are valued highly in many industrial industries and are expensive assets. In addition to their initial expense, they demand a large maintenance budget in order to guarantee output in respectable and safe working conditions. In order to avoid extreme repercussions, including the loss of lives, these assets must be carefully operated under experienced, well-trained supervision and subject to rigorous maintenance schedules and safety activities. However, this investigation is carried out with the help of the FMEA method, considering the previous literature\u27s studies of boiler accidents in Asia so far. Phase I has detailed information about boilers and Asian boiler accidents, and this research paper explains its nature. Subsequently, based on the data obtained in Phase I, an FMEA model will be developed in Phase II to highlight key boiler safety points. This research helps boiler manufacturers, boiler-related entrepreneurs, and boiler users to ensure maximum safety and identify any new things related to boiler safety

Multi-Agent Systems and Complex Networks: Review and Applications in Systems Engineering

Systems engineering is an ubiquitous discipline of Engineering overlapping industrial, chemical, mechanical, manufacturing, control, software, electrical, and civil engineering. It provides tools for dealing with the complexity and dynamics related to the optimisation of physical, natural, and virtual systems management. This paper presents a review of how multi-agent systems and complex networks theory are brought together to address systems engineering and management problems. The review also encompasses current and future research directions both for theoretical fundamentals and applications in the industry. This is made by considering trends such as mesoscale, multiscale, and multilayer networks along with the state-of-art analysis on network dynamics and intelligent networks. Critical and smart infrastructure, manufacturing processes, and supply chain networks are instances of research topics for which this literature review is highly relevant

Preventing Wide Area Blackouts in Transmission Systems: A New Approach for Intentional Controlled Islanding using Power Flow Tracing

A novel method to reduce the impact of wide area blackouts in transmission networks is presented. Millions of customers are affected each year due to blackouts. Splitting a transmission system into smaller islands could significantly reduce the effect of these blackouts. Large blackouts are typically a result of cascading faults which propagate throughout a network where Intentional Controlled Islanding (ICI) has the advantage of containing faults to smaller regions and stop them cascading further. Existing methodologies for ICI are typically calculated offline and will form pre-determined islands which can often lead to excessive splits. This thesis developed an ICI approach based on real time information which will calculate an islanding solution quickly in order to provide a ‘just-in-time’ strategy. The advantage of this method is that the island solution is designed based on the current operating point, but well also be designed for the particular disturbance location and hence will avoid unnecessary islanding. The new method will use a power flow tracing technique to find a boundary around a disturbance which forms the island that will be cut. The tracing method required only power flow information and so, can be computed quite quickly. The action of islanding itself can be a significant disturbance, therefore any islanding solution should aim to add as little stress as possible to the system. While methods which minimise the power imbalance and total power disrupted due to splitting are well documented, there has been little study into the effect islanding would have on voltage. There a new approach to consider the effects that islanding will have on the voltage stability of the system is developed. The ICI method is based on forming an island specific to a disturbance. If the location of a source is known along with information that a blackout is imminent, the methodology will find the best island in which to contain that disturbance. This is a slightly different approach to existing methods which will form islands independent of disturbance location knowledge. An area of influence is found around a node using power flow tracing, which consists of the strongly connected elements to the disturbance. Therefore, low power flows can be disconnected. This area of influence forms the island that will be disconnected, leaving the rest of the system intact. Hence minimising the number of islands formed. Finally the methodology is compared to the existing methods to show that the new tool developed in this thesis can find better solutions and that a new way of thinking about power system ICI can be put forward

Infrastructure Interdependencies: Opportunities from Complexity

Infrastructure networks, such as those for energy, transportation, and telecommunications, perform key functions for society. Although such systems have largely been developed and managed in isolation, infrastructure now functions as a system of systems, exhibiting complex interdependencies that can leave critical functions vulnerable to cascade failure. Consequently, research efforts and management strategies have focused on risks and negative aspects of complexity. This paper explores how interdependencies can be seen positively, representing opportunities to increase organizational resilience and sustainability. A typology is presented for classifying positive interdependencies, drawing on fundamental principles in ecology and validated using case studies. Understanding opportunities that arise from interdependency will enable better understanding and management of infrastructure complexity, which in turn will allow the use of such complexity to the advantage of society. Integrative thinking is necessary not only for mitigating risk but also for identifying innovations to make systems and organizations more sustainable and resilient

Infrastructure interdependencies : opportunities from complexity

Infrastructure networks, such as those for energy, transportation, and telecommunications, perform key functions for society. Although such systems have largely been developed and managed in isolation, infrastructure now functions as a system of systems, exhibiting complex interdependencies that can leave critical functions vulnerable to cascade failure. Consequently, research efforts and management strategies have focused on risks and negative aspects of complexity. This paper explores how interdependencies can be seen positively, representing opportunities to increase organizational resilience and sustainability. A typology is presented for classifying positive interdependencies, drawing on fundamental principles in ecology and validated using case studies. Understanding opportunities that arise from interdependency will enable better understanding and management of infrastructure complexity, which in turn will allow the use of such complexity to the advantage of society. Integrative thinking is necessary not only for mitigating risk but also for identifying innovations to make systems and organizations more sustainable and resilient