Critical Infrastructure Management Research Articles

Vulnerability of the Infrastructure: Risk Management and Implementation of the Information Systems

This article focuses on a comprehensive view of the connection between infrastructure, risks, and Geographic Information System (GIS). In the context of the current era, where critical infrastructure faces various threats and risks, it is essential to explore new methods and technologies that enable better identification, assessment, and management of these challenges. The first part of the article analyzes the current state of critical infrastructure and its connection to risks. Understanding how various threats, from natural disasters to cyber-attacks, affect infrastructure elements is crucial for effective protection and resilience. The second part examines the benefits and uses of Geographic Information Systems (GIS) in the context of risk assessment and management of critical infrastructure. GIS provides tools for collecting, analyzing, and visualizing spatial data, improving the ability to identify key risk areas and their interconnections. The results of this paper demonstrate how effectively linking these elements can enhance the resilience of critical infrastructure to various hazards.Overall, this article provides an overview of current trends in connecting infrastructure, risks, and Information Systems, emphasizing the importance of this comprehensive approach to ensuring the security and sustainability of critical infrastructure.

Impact of space systems capabilities and their role as critical infrastructure

The cyber domain has led to growth in current satellite capabilities, which have become essential due to the increased use of both civil and military critical infrastructure (CI) management systems. In recent decades, outer space has proven to be an increasingly critical sector for the international management of commercial CI, with private operators acting on both multi- and transnational levels. However, the space domain is characterised by not only opportunities but also risks and threats. As the security implications of space were not sufficiently considered at the beginning of the space era, some of the predominant risks currently extend into the commercial sphere. These risks must be considered to ensure the resilience of connected CIs in outer space. Security is a vital issue in the cyber and space domains and should be considered in every phase of a space system's life cycle, from the development and manufacturing of space assets to their deployment and end of life. This involves CI in several sectors, each of which exhibits different but interrelated risks. For example, telecommunications and location systems increasingly require the use of CI, which creates a fragile interdependence that is extremely vulnerable to threats. This paper underlines the importance of recognising space systems as CI and emphasises the need for a better integration of these assets in a system-of-systems analysis. The consequences of global satellite disruption on terrestrial CI are used to support this view. In such a disruptive scenario, mitigation measures based on in-orbit servicing or responsive space capabilities, for example, would allow CI to be restored to first ensure national security followed by commercial activities. Moreover, this paper provides an overview of the legal and policy aspects of using space systems’ capabilities in CI to better understand their implications and encourage the development of recommendations.

A surrogate deterioration model of debris retention systems towards cost-effective maintenance strategies and increased protection efficacy

Protection systems are usually implemented in mountains aiming to resist natural dangerous phenomena. As any other critical infrastructure, protection systems should always withstand and operate efficiently as they guarantee the safety of people and protect socio-economic assets. However, the efficacy of these systems decreases with the increase of the deterioration level of the interdependent components, which constitute them. To provide desirable operation over their lifetime, the management of protection systems is of paramount importance. A major key issue in such critical infrastructure management is to optimize the cost effectiveness of maintenance actions while maintaining a sufficient protection efficacy. This study proposes a decision-aiding model to assess different maintenance strategies applied to a protection system against debris flows. The model is constructed using physics-based stochastic Petri nets. It incorporates (1) a stochastic deterioration model, which is a surrogate model of a physics-based model developed for building deterioration trajectories of the system and (2) maintenance model that permits assessing the cost and efficiency of maintenance strategies. This study addresses the case of a debris retention system, in which the progressive filling of its basin by debris materials is modeled. This is followed by assessing several maintenance strategies concerning the cleaning of the basin. A simple sensitivity analysis is also carried out in order to check the effect of the uncertainty that invades the model’s inputs on maintenance decisions. A numerical analysis is performed using real data of the retention system located in the Claret torrent in France and subjected to debris flows over a period of 50 years.

Risk management of critical information infrastructure: threats-vulnerabilities-consequences

Today, interaction between people and objects, including industrial ones, has become an integral part of our everyday life. Access to communications, finance, and all forms of information management and permission to use them can be obtained from almost anywhere using compact devices.
 For example, operators can remotely control individual sectors and control operations in several areas at the same time, surgeons can operate on patients thousands of miles away, and car manufacturers can detect when one of their vehicles has been in an accident within a few seconds after the accident.
 As a result of the spread of the Internet and wireless data networks, the interconnection of so much data, technology and network equipment and devices has quickly become the basis of modern society. At present, we have become a knowledge-based society that often relies on technology to execute or support almost all tasks and functions of human life. Undoubtedly, this has greatly expanded the range of tasks to be solved, but at the same time, the society became much more vulnerable to threats in information and communication systems.
 The vulnerability is explained by the fact that at some point most of the production of different directions and industries is supported by the introduction, storage and search of data/information in a interconnected network of hard disks and data servers, locally or remotely located. And at each of these stages there is an opportunity to steal data, bypass protection, manipulate or replace information. But the risks associated with unintentional accidents caused by human errors, system failures, incompatibility or other unexpected problems, as well as “natural disasters,” must also be taken into account.
 Therefore, the security of computer or cyber systems is a matter of national security. Actually, cyber-threats are so great that more and more security experts are pointing out that protection of cyber systems and data is more of a problem than terrorism. Given the scale of the threat (in terms of cyberattacks) and the actual damage it can be argued, certain systems and structures are at risk [1, 2]. It is proved that hackers can break into government and business websites, steal personal data, change the traffic light scheme, accelerate and slow down travel, and much more.
 As an example, the implementation of a specially created malware program - Stuxnet. The effects of its use were the self-destruction in 2010 of dozens of centrifuges, which supported Iranʼs nuclear program [3, 4]. Some experts think that Stuxnet was created not by independent attackers and possibly with the support of the government. Thus, as a conclusion, it can be confirmed that hackers operate from anywhere in the world, and the links and boundaries between cyberspace and physical systems are sufficiently leveled. Thus, as a conclusion, it can be confirmed that intruders operate from anywhere in the world, and the links and borders between cyberspace and physical systems are sufficiently leveled.
 Society is increasingly faced with the fact that a group or even a person armed with a complex computer virus or knowledge about the vulnerability of software or hardware can cause a lot of physical damage to people’s lives or physical destruction, impose significant social or economic damage, and so on. For example, there are facts published by the Financial times on May 8, 2012 (http://on.ft.com/1wviXHW) that an unknown group for many years is trying to penetrate into the systems of managing the networks of gas pipelines of the USA. At the end of 2014, the National Oceanic and Atmospheric Administration of the United States announced that hackers from China successfully broke and destroyed American satellite networks, causing loss of services related to the prediction of various natural cataclysms, air flight corridors, navigation and other industries within a few days (http://wapo.st/1u7N9dJ).
 As a rule, the critical infrastructure includes power and transport main networks, oil and gas pipelines, sea ports, high-speed and governmental communication channels, systems of life support (water and heat supply) of mega-cities, waste management, emergency services and emergency response services, high-tech enterprises and enterprises of military-industrial complex, as well as central authorities.
 The government critical information infrastructure is only one of many important systems and networks that create our modern society. Therefore, the state and society are fully dependent on the functioning of different objects and subjects of critical information infrastructure, and the loss of integrity of any of them can lead to various kinds of failures (termination of production and transfer of electricity, temporary and long-term interruptions, improper access to medical care, and much more). Each state is a separate critical information infrastructure, but cooperation between states takes place within the framework of global critical information infrastructure. At the same time, large investments in each sector of critical information infrastructure have led to an increase in economic development rates and improvement in the quality of life.

Structural performance of aged Reinforced Autoclaved Aerated Concrete (RAAC) roof panels

AbstractReinforced Autoclaved Aerated Concrete (RAAC) is a lightweight, aerated cementitious material with no coarse aggregate, hence the material properties and structural behavior vary significantly compared with “traditional” reinforced concrete. It was a popular form of precast concrete panelized construction in the 1970s, especially in critical infrastructure such as hospitals, schools, and government buildings, and many of these structures are now at the end of their design life.Although the quality of contemporary RAAC precast elements and structures is considered to be good, concerns exist regarding the durability, serviceability and structural reliability of 40–50 year old RAAC panels still in service.Ongoing survey regimes and preliminary site observations and investigations of multiples structures in the United Kingdom have revealed significant problems in a small number of panels such as excessive cracking and deflection, insufficient cover, and reinforcement that is corroding and/or incorrectly placed.This paper therefore presents data on the structural performance and integrity of aged RAAC panels from the 1960s and 70s still in service in the United Kingdom, and presents the outcomes of the most significant and largest research project in the United Kingdom in the last 10 years, which investigated the material properties, structural performance, and monitoring strategies of aged RAAC panels. Structural testing on full scale panels in the laboratory and in situ have been conducted, together with petrographical examination and computational finite element modeling of RAAC panels form different structures and locations around the United Kingdom.The research has developed considerable new knowledge and understanding regarding the structural and material performance of aged RAAC panels and their associated failure modes, which will have significant implications for the repair, monitoring and management of these national critical infrastructure.

Approaches to the intellectualization of information and telecommunication networks security control in transport

The specifics of modern information and telecommunication networks in transport, as an object of information security control, are investigated. The main trends in the development of information and telecommunication network protection technologies (TNPT) have been identified. The presence of the interrelation of the main integrative properties: readiness, mobility, throughput, stealth, accessibility, manageability, which is a consequence of the convergence of information transmission and processing technologies, is noted. A new integrative property of ITCS has become the presence and characteristics of distributed system memory, which allows storing transmitted messages for a certain time. An important feature of modern TNPT is the presence of artificial intelligence, which is formed on the basis of information and algorithmic support of modern TNPT, providing flexibility of the system behavior. These trends indicate the transformation of TNPT into a supersystem, the management tasks of which are insufficiently investigated at present. The purpose of this work is to study new approaches to ensuring the safety management of modern TNPT critical infrastructure, which includes modern systems of sea and river transport, taking into account their features. The object of the study is the information security control system of modern TNPT. The subject of the study is the scientific and methodological support of the TNPT critical infrastructure control. The research objectives are to analyze existing and develop new conceptual frameworks, as well as approaches to improving the TNPT information security control system based on intellectualization methods. The analysis of the existing methodology for managing complex organizational and technical systems and information security control technologies is carried out. The concept of TNPT information security control is formalized schematically. The analysis of the existing approach to the organization of the TNPT information security control process is carried out. The tasks of control intellectualization are defined. The problem of ensuring the efficiency and reliability of the TNPT control is formulated. The main scientific tasks of the development of the TNPT information security control methodology are defined.

Cybersecurity of the Power Production and Distribution of Critical Infrastructure

The paper presents a structured, comprehensive, and universally applicable approach to the management of cyber security of the power production and distribution of critical electricity national infrastructure. A complete and comprehensive Program based on current legislation and established standards is the basis of cyber security management of critical power infrastructure. Mutually complementary activities of risk assessment and Business Impact Analysis BIA achieve a satisfactory level of industrial processes continuity of critical electric infrastructure. Vulnerabilities with associated risks against the continuity and integrity of the industrial processes of electricity production and distribution based on underlying national critical infrastructure, and newly created vulnerabilities as a result of the consequent deregulation and liberalization of the electricity market, such as the service flexibility of the electricity distribution system, aggregation and energy communities, e-mobility, balancing, auxiliary services, congestion management, and consumption management, have yet to be incorporated and appropriately treated within the framework defined by the Program and presented in this paper.

Physics-based probabilistic assessment of creep-fatigue failure for pressurized components

To achieve a high-reliability design of high-temperature structures with a feasible balance between accuracy and efficiency, the physics-based probabilistic assessment for creep-fatigue failure is proposed under the probabilistic Linear Matching Method (pLMM) framework. At the physical level, the structural failure mechanism is reflected in the prepared training database, which is generated by the direct method procedures. And to efficiently express the relationship between design parameters and structural responses implicitly, the direct method-driven artificial neural network is built with the superior fitting quality of damage and lifetime. With the benchmarks provided, the applicability of the proposed probabilistic analysis approach for risk management of critical infrastructures is demonstrated, where the reliability-based creep-fatigue evaluation diagram is established according to different requirements. Furthermore, a novel data classification scheme is proposed to deal with the randomness in creep damage-dominated probabilistic assessment.

The Impact of Edge Computing on the Industrial Internet of Things

The emergence of the Industrial Internet of Things (IIoT) has improved the management of industrial operations and processes. IIoT involves collecting and processing data from a vast array of sensors deployed across industrial complexes. This enables the measurement of the efficiency of industrial processes, monitoring the health of machinery, optimisation of operations, and response to real-time events. In its application, IIoT underpins the operation of critical infrastructure in sectors including manufacturing and utilities. Maintaining the availability and resilience of critical infrastructure against internal and external threats is essential to minimise disruptions that could have a debilitating effect on a nation’s economy. Although internal threats can lead to a critical infrastructure’s downtime, external threats through cyberattacks also pose a significant threat. Historical events have demonstrated that the successful disruption of critical infrastructure can lead to the loss of human life, the interruption of necessary economic activities and national security concerns. Therefore, the availability of resilient critical infrastructures is vital to the well-being of a country. In this context, the paper compares the deployment of traditional IIoT to that of edge computing for the storage and processing of data. Traditional IIoT relies on a centralised server for data storage and processing, which is insufficient as IIoT environments cannot tolerate delays in responding to real-time events. Conversely, edge computing allows for data processing at the edge, closer to the data source, which plays a crucial role in enabling IIoT devices to respond to real-time events by reducing decision-making latency. Moreover, the decentralised nature of edge computing reduces the reliance on a centralised server by only sending required data to the cloud for further processing. Although edge computing enhances IIoT deployments, a notable concern is a resultant increase in the attack surface of IIoT environments, which consequently restricts its implementation. Exploratory research is conducted to explore the integration of edge computing into IIoT environments with a focus on improving the management and operation of critical infrastructures. A review of the current literature is performed to identify and discuss security concerns prevalent in edge computing-enabled IIoT environments and proposed mitigation strategies.

Ground infrastructure monitoring in coastal areas using time-series inSAR technology: the case study of Pudong International Airport, Shanghai

ABSTRACT Shanghai Pudong International Airport (PDIA), with its east side built along the coast with weak geological conditions, is prone to uneven foundation settlement due to the consolidation and compression of soil and erosion of coastal tides, affecting the safe operation of the airport. Therefore, it is crucial to conduct dynamic subsidence monitoring within the airport, especially in the runway area. 29 scenes of ascending track Sentinel-1A radar images from August 2016 to June 2018 are selected to perform surface deformation inversion based on PS-InSAR and improved SBAS-InSAR for PDIA and its around coastal area. Through cross-validation, the reliability of the time-series InSAR technique for dynamic monitoring of surface deformation of coastal zone infrastructures is confirmed. The results show severely uneven settlement. By combining the monitoring results with the local geological and hydrological dataset, the driving factors of differential deformation of the infrastructures are analyzed, including stratigraphic geological conditions, ground loadings, foundation treatment methods, water erosion, and groundwater level changes. Finally, the time-series deformation characteristics and the causes of PDIA's runway are emphasized based on the PS deformation results. This case provides a reference for the safety management of critical infrastructure in coastal areas using advanced InSAR technique.

Real Time Automation and Ratio Control Using PLC & SCADA in Industry 4.0

Industrial Control Systems (ICS) and SCADA (Supervisory Control and Data Acquisition) systems play a critical role in the management and regulation of critical infrastructure. SCADA systems brings us closer to the real-time application world. All process and equipment control capability is typically provided by a Distributed Control System (DCS) in industries such as power stations, agricultural systems, chemical and water treatment plants. Instead of control through DCS, this paper proposes a SCADA and PLC (Programmable Logic Controller) system to control the ratio control division and the assembly line division inside the chemical plant. A specific design and implementation method for development of SCADA/PLC based real time ratio control and automated assembly line system in a chemical plant is introduced. The assembly line division is further divided into sorting stage, filling stage and the auxiliary stage, which includes the capping unit, labelling unit and then the storage. In the ratio control division, we have defined the levels inside the mixer and ratio of the raw materials through human machine interface (HMI) panel. The ratio of raw materials is kept constant on the basis of flow rates of wild stream and manipulated stream. There is a flexibility in defining new levels and the ratios of the raw materials inside the mixer. But here we taken the predefined levels (low, medium, high) and ratios (3:4, 2:1, 2:5). Control valves are used for regulating the flow of the compositions. In the assembly line division, the containers are sorted on the basis of size and type of material used i.e., big sized metallic containers and small sized non-metallic containers by inductive and capacitive proximity sensors. All the processes are facilitated with laser beam type or reflective type sensors on the conveyor system. Building a highly stable and dependable PLC/SCADA system instead of Distributed Control System is required to achieve automatic management and control of chemical industry processes to reduce waste manpower and physical resources, as well as to improve worker safety.

A Systemic Review of the Cybersecurity Challenges in Australian Water Infrastructure Management

Cybersecurity risks have become obstinate problems for critical water infrastructure management in Australia and worldwide. Water management in Australia involves a vast complex of smart technical control systems interconnected with several networks, making the infrastructure susceptible to cyber-attacks. Therefore, ensuring the use of security mechanisms in the control system modules and communication networks for sensors and actuators is vital. The statistics show that Australia is facing frequent cyber-attacks, most of which are either undetected or overlooked or require immediate response. To address these cyber risks, Australia has changed from a country with negligible recognition of attacks on critical infrastructure to a country with improved capability to manage cyber warfare. However, little attention is paid to reducing the risk of attacks to the critical water infrastructure. This study aims to evaluate Australia’s current cybersecurity attack landscape and the implemented controls for water infrastructure using a systematic literature review (SLR). This study also compares Australia in the context of global developments and proposes future research directions. The synthesis of the evidence from 271 studies in this review indicates the importance of managing security vulnerabilities and threats in SCADA water control systems, including the need to upgrade the contemporary water security architecture to mitigate emerging risks. Moreover, human resource development with a specific focus on security awareness and training for SCADA employees is found to be lacking, which will be essential for alleviating cyber threats to the water infrastructure in Australia.

Framework for Operational Resilience Management of Critical Infrastructures and Organizations

Progressing digitalization and networking of systems and organizations representing Critical Infrastructures opens promising new potentials and opportunities, which on the downside, are accompanied by rising complexity and increasingly opaque interdependencies. The consequently increasing lack of knowledge leads to uncertainties affecting risk assessment and decision-making in case of adverse events. This trend motivated recent discussions and developments in risk science, emphasizing the need to handle such uncertainties. Complementarily, research in the resilience domain focuses on system capabilities to handle surprising hazardous situations. Several frameworks presented in the literature aim at combining both perspectives but either lack the focus on operational management, have a rather theoretical approach, or are designed for specific applications. Based on this observation, we propose an approach that integrates resilience management into the actual operation of Critical Infrastructure Systems and Organizations by providing an operational process that coordinates the fundamental resilience capabilities of responding, monitoring, anticipation, and learning. Furthermore, we tackle the challenge of uncertainties resulting from a lack of knowledge by aligning the concepts of digital twin and resilience management. The proposed framework is extensively discussed, and required processes are presented in detail. Eventually, its applicability and potential are reviewed by means of a complex hazardous situation at a Bavarian district heating power plant.

A model for managing the security of maritime critical infrastructure under the conditions of the fourth industrial revolution

The primary objective of the author of this paper is to propose a preliminary and theoretical model of security management of maritime critical infrastructure under the conditions of the fourth industrial revolution. The proposed model in the definition is to be comprehensive in terms of shaping information security management. The article is also an attempt to capture the main threats in the sphere of information security management during the management of critical infrastructure. In addition, the author‘s intention is to provoke/open a discussion on this topic, because as is evident from numerous scientific studies, the awareness of the negative consequences of progress is essential to take correct actions to minimize their impact.

Просторове забезпечення управління сталим господарюванням у критичній інфраструктурі в особливий період

The article proposes to use the methodological provisions for the development and implementation in practice of a spatial three-level complex of monitoring programs (general/standard, operational/crisis and background/scientific), which was formed taking into account the current geopolitical and internal economic situation in the state according to the block principle of configurational transformation in the quality of the National Spatial System for Monitoring the Effectiveness of Management of Sustainable Management in Critical Infrastructure. The target activity of the National Monitoring System has been formulated, which should be aimed at: a) organization of information support at the level of decision-making and control over the execution of assignments and the creation of a permanent information testing ground for critical infrastructure objects; b) obtaining, in addition to technical-economic, technological and financial information, also information related to the dynamics of threats to the sustainable management of critical infrastructure and its submission to state bodies, management and management entities, etc.; c) the use of measures directly aimed at increasing the level of protection against identified threats and risks, which should be successfully used for decision-making in various economic and business processes. The main provisions of the cybernetic theory were used to determine the key problems of critical infrastructure in the unstable conditions of economic and military aggression, which makes it possible to consider the self-organization of the state entity as a process of achieving a dynamic balance between the management system of sustainable management in critical infrastructure and its environment.

Foundation Treatment in Urban Underground Engineering Using Big Data Analysis for Smart City Applications

A core element of the sustainable approach to global living quality improvement can now become the intensive and organized usage of underground space. There is a growing interest in underground building and growth worldwide. The reduced consumption of electricity, effective preservation of green land, sustainable wastewater and sewage treatment, efficient reverse degradation of the urban environment, and reliable critical infrastructure management can improve the quality of life. At the same time, technological innovations such as artificial intelligence (AI), cloud computing (CC), the internet of things (IoT), and big data analytics (BDA) play a significant role in improved quality of life. Hence, this study aims to integrate the technological innovations in urban underground engineering to ensure a high quality of life. Thus, this study uses big data analytics to carry out the status quo of foundation treatment and proposes a conceptual framework named the BDA with IoT on urban underground engineering (BI0T-UUE). This framework connects hidden features with various high-level sensing sources and practical predictive model characterization to lower building costs, productive infrastructure management, preparedness for disasters, and modern community smart services. The IoT integration gives an optimum opportunity to work towards the functionality of ‘‘digital doubles’’ of secret infrastructure, both economical and scalable, with the increasing sophistication and tooling of the underworld. The simulation analysis ensures the highest efficiency and cost-effectiveness of the underground engineering with a value of 96.54% and 97.46%.

Some problems of security management of “Smart cities” and ways to solve them based on the criteria modeling methodology

In the EU countries, South Korea, China, Russia and India, smart city technologies are being introduced that allow improving the efficiency of critical infrastructure management. In large systems with many critical components, such as smart cities, there are always a huge number of threats and vulnerabilities. Often in such cases, a security system is built against a limited number of threats and vulnerabilities. It is necessary to control not how vulnerable, but how thorough, high-quality, reliable security systems are. And if they are not controlled, then large cognitive distortions can appear in security management. Criteria modeling methodology) allow us to solve this problem and ensure the efficient functioning of a smart city. Criteria modeling methods make it possible to significantly facilitate the control of security and stability of the entire set of cybernetic systems and smart city technologies. The article describes a criteria modeling methodology that allows you to identify and take control of all threats and vulnerabilities, and above all those that cannot be eliminated. This methodology is described and the benefits of using it in smart city security management are given. The application of this methodology makes it possible to prevent the occurrence of cognitive distortions in security management, control existing vulnerabilities and timely redistribute resources allocated to security.

ANALYSIS OF CYBER RESISTANCE ASSESSMENT METHODS OF CRITICAL INFRASTRUCTURE

The availability of critical infrastructure through cyberspace makes national security dependent on the degree of its security. Critical infrastructure is a set of automated management systems, which provide the interaction of information and telecommunications networks that solve problems of public administration, defense, security and law enforcement, and others. The protection of critical infrastructure directly depends on the possession of the relevant structures of new weapons, the degree of its effectiveness, methods of use and means of protection against the same weapons of the enemy. It is necessary to address the issue of effective confrontation in cyberspace. The analysis of problems in the development of methods for assessing the functional stability of critical infrastructure in cyber confrontation requires the definition of basic methods and criteria that can be used in Ukraine to assess the stability of critical infrastructure. Cyber weapons, which carry out destructive information effects, are not weapons in the classical sense, because they do not physically damage the object of attack, but translate its information and automated control systems into a crisis mode of operation. The process of counteraction of two or more parties, in this form, is a cyber confrontation that is realized using a common common resource - the global information space. In the process of critical infrastructure management, cyber confrontation imposes additional requirements to ensure the sustainable operation of critical infrastructure. Stability is an integral property that is inextricably linked to the operating environment. Cyber resilience is an integrated indicator and is determined by cyber reliability, which reflects the ability to perform its tasks in a complex critical infrastructure management system in the context of information destructive influences.

A Hierarchical Resilience Enhancement Framework for Interdependent Critical Infrastructures

Resilience is becoming a key concept for risk assessment and safety management of interdependent critical infrastructures (ICIs). This work proposes a resilience enhancement framework for ICIs. With reference to the accidental event, ex-ante and ex-post solutions for enhancing system resilience are analysed and included into a hierarchical model of resilience enhancement strategies (RES). To provide specific resilience enhancement solutions for ICIs, we integrate the hierarchical model with a model predictive control-based dynamic model of ICI system operation. The relationships between the solutions implemented and their impacts on the system parameters are discussed. A multi-objective optimization (MOO) problem is defined, with the objectives of simultaneously minimizing RES cost and maximizing ICIs resilience. The fast non-dominated sorting genetic algorithm NSGA-II is used to solve the MOO problem. For exemplification, a case study is considered, involving interdependent natural gas network and electric power grid. The results show that the resilience enhancement framework is effective in finding optimal RESs for given ICIs.

Seismicity and seismic hazard assessment in West Africa

No in-depth seismic hazard study for West Africa (WA) has ever been conducted, as the regional earthquake catalogues are incomplete. Such lack of comprehensive seismic hazard study for the region has negatively affected the planning and development of critical infrastructure and disaster risk management. Therefore, this study aims to bridge the knowledge gap by applying modern techniques to updating the existing catalogues and assessing the seismic hazards for the region. We updated the current earthquake catalogue for WA using information from the International Seismological Centre, published information, and data from seismic stations in the region. The seismotectonic setting of WA is considered stable continental crust despite several recorded earthquakes occurring in the region, the largest being the June 22, 1939 earthquake of magnitude M6.8 with epicentre in Ghana. However, WA has also been classified as a region of shallow crustal seismicity. Therefore, we investigated both these research schools of thought and compared their results. For each scenario, three different ground-motion models (GMMs) were applied and combined to produce each hazard map using logic tree formalism with equal weights. The region was divided into five seismic source zones for computation of the earthquake recurrence parameters, with the same parameters computed for the entire WA region. The computed Gutenberg–Richter b-value, activity rates λ, and regional maximum possible magnitudes mmax for the five zones ranged from 0.84 to 1.0, 0.3–2.1, and 5.2–7.0, respectively. The calculated b-value, λ, and mmax for the entire region were 0.77, 4.1, and 7.2, respectively. The estimated b-value of 0.77 falls within the generally accepted range for tectonic seismicity. The seismic hazard predicted by GMMs for stable continental areas was higher than that predicted for shallow crustal seismicity in the investigated region. Therefore, our results confirmed that WA is characterised by stable continental crust. The highest hazard levels were observed in parts of Ghana, Togo, Guinea-Bissau, Guinea, and the Cameroon Volcanic Line region (CVL), ranging between 0.02 g and 0.03 g.