<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Donetsk National Technical University</institution>
          ,
          <addr-line>76, Sambirska Str., Drohobych, Lviv region, 82111</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>G. E. Pukhov Institute for Modeling in Energy Engineering of National Academy of Sciences of Ukraine</institution>
          ,
          <addr-line>15, Oleha Mudraka Str., Kyiv, 03164</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”</institution>
          ,
          <addr-line>37, Prospect Beresteiskyi (former Peremohy), Kyiv, Ukraine, 03056</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Taras Shevchenko National University of Kyiv</institution>
          ,
          <addr-line>60 Volodymyrska Street, Kyiv, 01033</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
      </contrib-group>
      <fpage>109</fpage>
      <lpage>124</lpage>
      <abstract>
        <p>Critical infrastructure ensures the stability of society, economic growth, and national security. This paper presents a tensor-based model for assessing infrastructure resilience, considering technical, economic, environmental, social, and managerial aspects. The proposed model represents infrastructure subsystems - generation, transportation, and resource consumption-across different operational phases: pre-disaster, crisis, and recovery. Tensor analysis enables a comprehensive evaluation of interactions between system components, multiple threat impacts, and resilience criteria such as functionality, recovery time, threat resistance, adaptability, and economic efficiency. By defining threat vectors for various disruptions, including cyberattacks, natural disasters, and technological failures, the model identifies vulnerabilities and provides insights for strengthening infrastructure resilience. The findings support strategic management, risk mitigation, and policy development in national security and engineering planning.</p>
      </abstract>
      <kwd-group>
        <kwd>resilience of critical infrastructures</kwd>
        <kwd>tensor analysis</kwd>
        <kwd>resilience criteria</kwd>
        <kwd>threat modeling</kwd>
        <kwd>risk management</kwd>
        <kwd>strategic planning</kwd>
        <kwd>multidimensional analysis</kwd>
        <kwd>system adaptability</kwd>
        <kwd>cyberattacks</kwd>
        <kwd>environmental sustainability</kwd>
        <kwd>1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Critical infrastructures, including energy, transportation, communications, water supply, and
healthcare, are essential for national security and economic stability. However, these systems face
increasing threats from natural disasters, cyberattacks, technological failures, and geopolitical
conflicts. Their interconnected nature makes resilience a key priority.</p>
      <p>Resilience defines a system’s ability to maintain functionality, resist external impacts, and recover
after crises. It involves technical, organizational, social, and economic factors that ensure adaptability
to dynamic threats. A structured approach to assessing resilience requires clear criteria,
mathematical modeling, and analytical methods.</p>
      <p>This paper explores tensor analysis as a tool for modeling resilient critical infrastructure. Tensor
models enable the evaluation of complex interactions between system components, threat scenarios,
and adaptive strategies. The proposed approach integrates technical, economic, and managerial
aspects to enhance infrastructure security and operational stability.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Literature Review</title>
      <p>
        The article [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] presents an innovative approach to assessing the resilience of critical infrastructure
under conditions of multi-level threats, particularly for transportation facilities as key components
of critical infrastructure. The authors have developed an adaptive methodology that integrates
various risk parameters, providing a robust foundation for decision-making during crises. This
approach serves as a basis for further research in infrastructure resilience and risk management.
      </p>
      <p>
        The following study [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] focuses on a novel framework for evaluating the resilience of
multicomponent critical infrastructure. Specifically, it demonstrates how modern approaches in
engineering systems management can enhance resilience to complex threats. To achieve this, the
authors pay significant attention to mathematical models for analyzing inter-system dependencies,
which are critical for ensuring the uninterrupted functioning of infrastructure during emergencies.
      </p>
      <p>
        In article [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], a quantitative method for evaluating the resilience of interdependent infrastructures
is proposed. The mathematical model developed by the authors enables the assessment of
functionality losses and recovery rates after emergency events. This approach is particularly relevant
as it considers interconnections between infrastructure components, making it valuable for practical
risk management solutions.
      </p>
      <p>
        The analysis of urban critical infrastructure resilience, exemplified by Ahvaz, Iran, is presented
in study [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. The authors employ an indicative approach to assess vulnerabilities in urban networks
such as water supply, electricity, and transportation. This method emphasizes the integration of
environmental, social, and technical factors, thereby enhancing the overall resilience of urban
systems to crises.
      </p>
      <p>
        The work [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] proposes metrics and frameworks for analyzing the resilience of engineering and
infrastructure systems. The research focuses on methods for evaluating systems' ability to withstand
external impacts, quickly adapt, and restore functionality. This study provides a theoretical
foundation for further works in resilience and risk management for infrastructure.
      </p>
      <p>
        Research [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] emphasizes the impact of dynamic cost changes on assessing infrastructure
resilience. It highlights the importance of incorporating time factors to improve the accuracy of
resilience forecasting, developing methodologies for adaptive risk assessment and infrastructure
management.
      </p>
      <p>
        The development of metrics and methods for quantitative assessment of the resilience of power
systems is presented in study [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. The authors propose an integrative approach to analyzing
operational and structural resilience. The suggested metrics allow the formulation of strategies for
risk minimization and enhancing the reliability of energy supply systems.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] presents a comprehensive framework for evaluating the resilience of critical
infrastructure components by incorporating technical, organizational, and social dimensions. This
multidimensional approach aids in designing measures to enhance resilience across different sectors
of critical infrastructure, offering a holistic view of how various factors interact.
      </p>
      <p>
        Study [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] introduces a methodology for assessing the resilience of networked infrastructures,
with a focus on the interdependencies among system elements and the effects of their potential
failure. The findings provide a foundation for creating effective risk management strategies to
maintain and strengthen critical infrastructure resilience.
      </p>
      <p>
        In article [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], operational models for analyzing infrastructure resilience are examined. The study
focuses on identifying vulnerabilities in networks and finding optimal solutions for ensuring
continuous infrastructure operation during crises, making this work a significant step in developing
resilience strategies.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] explores the resilience of power systems, considering approaches to assessing critical
infrastructure resilience and criteria established by government policies. The work presents an
interdisciplinary approach integrating technical and regulatory aspects to enhance the reliability of
energy infrastructure.
      </p>
      <p>
        Research [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] highlights the use of expert judgment to assess the resilience of critical
infrastructures. The authors propose a model that incorporates subjective expert evaluations for
quantitatively determining resilience levels. This study is useful for rapid risk analysis in situations
with limited data.
      </p>
      <p>
        In article [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], the concept of resilience curves for infrastructure is presented. The study identifies
new performance metrics and data aggregation methods to evaluate the effectiveness of
infrastructure systems during emergencies. The proposed approach allows for a detailed analysis of
recovery dynamics and functionality losses.
      </p>
      <p>
        Study [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] introduces a framework for evaluating the resilience of both infrastructural and
economic systems. It offers an in-depth analysis of methods for modeling interdependencies among
system components, facilitating a clearer understanding of their responses to different types of
threats.
      </p>
      <p>
        Work [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] presents a scenario-based methodology for assessing the resilience of critical
infrastructures, with a particular focus on the seismic resilience of seaports. The authors develop a
multi-level approach that integrates scenario modeling and impact assessment, enabling precise
forecasting of potential risks.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] conducts a systematic review of quantitative resilience indicators for water
infrastructure systems. The research focuses on developing metrics that quantify the ability of water
systems to recover functionality after adverse impacts. This study serves as a foundation for strategic
decision-making in water resource management.
      </p>
      <p>
        Study [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] analyzes approaches to measuring the resilience of transportation infrastructure. The
work focuses on developing indicators and methods for resilience assessment in the context of
transport systems, although it provides limited information on the specifics of the infrastructure.
      </p>
      <p>
        In article [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ], the performance of green infrastructure is investigated through the lens of urban
resilience. The authors propose an analytical methodology for assessing the impact of green
infrastructure on the recoverability of urban systems, considering environmental and
socioeconomic aspects.
      </p>
      <p>
        Research [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] focuses on evaluating and enhancing organizational resilience in Slovakia's critical
infrastructure. The work presents a multi-level approach to strengthening organizational capacity
for adaptation and crisis response.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] examines principles and criteria for evaluating the resilience of energy systems in
urban environments. This review study highlights key factors ensuring the reliability and continuity
of energy supply under rapidly changing conditions.
      </p>
      <p>
        In article [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ], time-dependent resilience of urban infrastructural systems is assessed. The authors
propose a methodology for resilience evaluation that accounts for dynamic changes in infrastructure
functionality over time, enabling more precise planning for resilience improvements.
      </p>
      <p>
        Study [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ] offers a continuous and multidimensional assessment of resilience based on functional
analysis for interconnected systems. This work emphasizes the importance of an integrated approach
to infrastructure resilience assessment, where each element interacts with others, creating a complex
network of interdependencies.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ] explores metrics and methods for measuring resilience in transportation
infrastructure. The work discusses the current state of development of criteria and methodologies
for resilience assessment in transport systems, particularly in the context of climate change and
extreme events.
      </p>
      <p>
        Research [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ] focuses on the assessment of infrastructure resilience, exploring different methods
and approaches for measuring how infrastructure systems adapt to changing conditions.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ] examines the integrity of infrastructure systems through a systemic perspective,
highlighting the significance of integrating multiple components to ensure they can operate
cohesively under unexpected circumstances.
      </p>
      <p>
        In article [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ], the concept of system resilience in the context of infrastructure is analyzed using
Latvia as a case study. The research applies theoretical approaches to assessing infrastructure
resilience in countries with transitional economies.
      </p>
      <p>
        Study [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ] proposes a unified approach to assessing the resilience and sustainability of urban
infrastructure. This approach incorporates various parameters to evaluate infrastructure resilience
under climate change and extreme events.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ] proposes a qualitative methodology for evaluating the performance of IT
infrastructure elements, considering technical characteristics and operating conditions. The author
developed a model to assess the reliability and performance of IT system components, predict
potential failures, and optimize operations, emphasizing the approach's versatility for various types
of infrastructure.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ] discusses a new approach to measuring the resilience of transportation infrastructure
networks. The work focuses on developing methods for resilience assessment that consider various
extreme event scenarios.
      </p>
      <p>
        Research [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ] addresses the assessment of resilience in interdependent infrastructure systems,
emphasizing the modeling and analysis of joint recovery processes following damage.
      </p>
      <p>
        Article [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ] evaluates the resilience of interdependent infrastructures by examining different
response strategies, with a focus on their capacity to recover during major disasters or crises.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Results</title>
      <sec id="sec-3-1">
        <title>3.1. Key Criteria for Critical Infrastructure Resilience</title>
        <p>Based on the analysis of the literature, the main criteria for the resilience of critical infrastructures
have been identified (Table 1):









</p>
        <sec id="sec-3-1-1">
          <title>Infrastructure Functionality – assessment of the ability of infrastructure to perform its core</title>
          <p>functions during and after stress events (e.g., natural disasters or man-made catastrophes).</p>
        </sec>
        <sec id="sec-3-1-2">
          <title>Recovery Capability – the ability of infrastructure to quickly recover after damage or functional disruptions. This criterion includes time, resources, and measures needed to return to normal conditions.</title>
        </sec>
        <sec id="sec-3-1-3">
          <title>Resistance to External Threats – the ability of infrastructure to withstand extreme factors, such</title>
          <p>as natural disasters, technological accidents, economic and social crises.</p>
        </sec>
        <sec id="sec-3-1-4">
          <title>Flexibility and Adaptability – the capacity of infrastructure to adapt to new conditions and changes, such as climate change, technological advancements, or shifts in political and economic contexts.</title>
        </sec>
        <sec id="sec-3-1-5">
          <title>Economic Cost Assessment – evaluation of recovery costs after a disaster, including direct</title>
          <p>costs of restoration and indirect losses from service interruptions.</p>
        </sec>
        <sec id="sec-3-1-6">
          <title>Integration with Other Systems – assessment of how infrastructure systems interact and depend on each other. This criterion is important for identifying how one failure may affect others.</title>
        </sec>
        <sec id="sec-3-1-7">
          <title>Instant Analysis and Forecasting – utilization of data for real-time evaluation of the current state of infrastructure and prediction of potential issues.</title>
        </sec>
        <sec id="sec-3-1-8">
          <title>Flexibility of Management Structures – the ability of management bodies and organizations responsible for infrastructure to quickly adapt to new conditions, organize effective responses, and coordinate recovery efforts.</title>
        </sec>
        <sec id="sec-3-1-9">
          <title>Data Security and Protection – ensuring the security of data and information systems against</title>
          <p>cyberattacks and other threats that may disrupt infrastructure operations.</p>
        </sec>
        <sec id="sec-3-1-10">
          <title>Environmental Sustainability – assessment of the extent to which infrastructure complies with environmental standards and can adapt to changes in the surrounding environment. 112</title>
          <p>Criterion
Infrastructure</p>
          <p>Functionality
Recovery Capability</p>
          <p>Resistance to
External Threats
Flexibility and
Adaptability
Economic Cost</p>
          <p>Assessment
Integration with</p>
          <p>Other Systems
Instant Analysis and</p>
          <p>Forecasting
Flexibility of
Management</p>
          <p>Structures
Data Security and</p>
          <p>Protection
Environmental
Sustainability</p>
          <p>Criterion Description Sources (References)</p>
        </sec>
        <sec id="sec-3-1-11">
          <title>Assessment of the ability of infrastructure [1], [6], [12], [17], to perform its core functions during and [19], [29] after stress events.</title>
        </sec>
        <sec id="sec-3-1-12">
          <title>The ability of infrastructure to quickly [2], [9], [14], [17], recover after damage or functional [18], [29] disruptions, including time, resources, and measures needed for restoration.</title>
        </sec>
        <sec id="sec-3-1-13">
          <title>The ability of infrastructure to withstand [3], [7], [15], [20], extreme factors, such as natural disasters, [24], [28] technological accidents, economic, and social crises.</title>
        </sec>
        <sec id="sec-3-1-14">
          <title>The capacity of infrastructure to adapt to [4], [12], [14], [17],</title>
          <p>
            new conditions and changes, such as [
            <xref ref-type="bibr" rid="ref26">26</xref>
            ], [
            <xref ref-type="bibr" rid="ref30">30</xref>
            ]
climate change, technological
advancements, or shifts in political and
economic contexts.
          </p>
        </sec>
        <sec id="sec-3-1-15">
          <title>Evaluation of recovery costs after a [8], [11], [18], [23], disaster, including direct restoration costs [28] and indirect losses from service interruptions.</title>
        </sec>
        <sec id="sec-3-1-16">
          <title>Assessment of how infrastructure systems [5], [11], [15], [18], interact and depend on each other, [22], [29] identifying how one failure may impact others.</title>
        </sec>
        <sec id="sec-3-1-17">
          <title>Utilization of data for real-time evaluation [6], [9], [19], [21], of the current state of infrastructure and [30] prediction of potential issues.</title>
        </sec>
        <sec id="sec-3-1-18">
          <title>The ability of management bodies and [5], [14], [20], [29],</title>
          <p>
            organizations responsible for [
            <xref ref-type="bibr" rid="ref30">30</xref>
            ]
infrastructure to quickly adapt to new
conditions, organize effective responses,
and coordinate recovery.
          </p>
          <p>
            Ensuring the security of data and [
            <xref ref-type="bibr" rid="ref13">13</xref>
            ], [
            <xref ref-type="bibr" rid="ref15">15</xref>
            ], [
            <xref ref-type="bibr" rid="ref17">17</xref>
            ], [
            <xref ref-type="bibr" rid="ref28">28</xref>
            ]
information systems against cyberattacks
and other threats that may disrupt
infrastructure operations.
          </p>
          <p>
            Assessment of the extent to which
infrastructure complies with
environmental standards and can adapt to
changes in the surrounding environment.
[
            <xref ref-type="bibr" rid="ref4">4</xref>
            ], [
            <xref ref-type="bibr" rid="ref7">7</xref>
            ], [
            <xref ref-type="bibr" rid="ref10">10</xref>
            ], [
            <xref ref-type="bibr" rid="ref15">15</xref>
            ],
[
            <xref ref-type="bibr" rid="ref27">27</xref>
            ]
utility systems),
post-disaster).
          </p>
          <p>


stages;
statistical data.</p>
          <p>Next, we will examine the tensor model of critical infrastructure resilience based on the identified
resilience criteria.</p>
        </sec>
      </sec>
      <sec id="sec-3-2">
        <title>3.2. Tensor Model of Resilient Critical Infrastructure</title>
        <p>To construct a tensor model of resilient critical infrastructure based on the defined criteria, each
criterion can be considered as a separate component interacting with others through specific
parameters. A tensor model is a multidimensional mathematical object that allows for the description
of interconnections between various characteristics of infrastructure and its resilience.</p>
        <p>Let T represent the tensor describing the resilient critical infrastructure. Each element of the
tensor corresponds to a specific resilience characteristic of the infrastructure, grouped according to
its various parameters. The model can be represented as a third-order tensor:
 – index representing individual resilience criteria,
 – index representing subsystems or components of infrastructure (e.g., energy, transportation,
 – index representing the time aspect or stages of recovery (e.g., pre-disaster, during disaster,</p>
        <sec id="sec-3-2-1">
          <title>Principles of the model operation are as follows:</title>
          <p>the tensor  , , defines all the interrelationships between resilience criteria, subsystems, and
for each stage  changes in infrastructure resilience can be assessed based on specific criteria,
as well as interdependencies between subsystems;
tensor parameters can be calculated based on expert assessments, mathematical models, or
The proposed model can easily be expanded by introducing additional tensors. For example, we
can introduce an additional threat tensor  , which demonstrates the impact of specific threats on the
resilience criteria of the system.</p>
          <p>Let there be  threats affecting the resilience of the system. Then, for each resilience criterion,
we have the following threat vector  , which reflects the impact of each threat on criterion  :</p>
          <p>The result of the impact of threats on the resilience of subsystems can be represented by tensor
 , composed of the corresponding matrices  , which contain the result of multiplying  by the
corresponding threat element  . Thus, for each criterion i we will obtain a matrix of size    ×  ,
where each element of this matrix is calculated as:

= (
…</p>
          <p>).</p>
          <p>, , =  , , ×  ,
where:
 , , – element of the matrix for criterion  , subsystem  and stage  for threat  .
 , , – element of the matrix for criterion  , subsystem  and stage  .</p>
          <p>– element of the threat vector for criterion  and threat  .</p>
          <p>The general appearance of the matrix  for each threat  is as follows:</p>
          <p>Additional tensors can also be introduced into the model, which, for example, describe
vulnerabilities and protection mechanisms within the system. Additionally, further interaction and
mutual influence rules between tensors can be defined.</p>
        </sec>
      </sec>
      <sec id="sec-3-3">
        <title>3.3. Scenarios for model research</title>
        <p>The model, built on multidimensional tensors for assessing system resilience under the influence
of threats, allows for a series of experimental studies to analyze systems in different scenarios:
1. Analysis of the impact of different threats on system resilience


</p>
        <sec id="sec-3-3-1">
          <title>Objective – to investigate how different types of threats affect different resilience criteria.</title>
          <p>Experiment:


change the values of tensor  to simulate varying threat intensities;
analyze the resulting tensor  to identify resilience criteria most affected by the
threats.</p>
        </sec>
        <sec id="sec-3-3-2">
          <title>Result – identification of the most vulnerable criteria or subsystems.</title>
          <p>2. Evaluation of the effectiveness of protection measures</p>
        </sec>
        <sec id="sec-3-3-3">
          <title>Objective – to verify how specific protective measures reduce the impact of threats.</title>
          <p>Experiment:
 add a correction tensor to  representing the influence of protective measures;
 recalculate  and compare it to the baseline value.</p>
          <p>Result – assessment of the effectiveness of specific measures.
3. Analysis of disaster scenarios










</p>
          <p></p>
        </sec>
        <sec id="sec-3-3-4">
          <title>Objective – to investigate how changes in one or more elements of  affect the resulting  .</title>
          <p>Experiment:

gradually change the threat values (e.g., increase or decrease the impact of a
specific threat on a specific criterion);
analyze the dynamic changes in  .</p>
        </sec>
        <sec id="sec-3-3-5">
          <title>Objective – to model various disaster scenarios and assess system resilience at each stage.</title>
          <p>Experiment:

for each stage (pre-disaster, during disaster, post-disaster), modify the
corresponding values of tensor  and analyze the changes in tensor  ;
 specifically, study how the system recovers after a disaster.</p>
        </sec>
        <sec id="sec-3-3-6">
          <title>Result – identification of critical stages requiring the most attention.</title>
          <p>4. Comparison of systems with different resilience characteristics</p>
        </sec>
        <sec id="sec-3-3-7">
          <title>Objective – to assess which system has higher resilience under the same threat conditions.</title>
          <p>Experiment:

use different initial values of tensor  (e.g., for different organizations, regions,
or system types);
 analyze the resulting tensors  and identify the systems with the best
performance.</p>
          <p>Result – ranking of systems based on resilience level.
5. Determination of system sensitivity to changes in threat intensity












</p>
        </sec>
        <sec id="sec-3-3-8">
          <title>Result – identification of critical threats with the most significant impact on the system.</title>
          <p>6. Determination of interrelationships between resilience criteria</p>
        </sec>
        <sec id="sec-3-3-9">
          <title>Objective – to find out how the impact of one threat on a specific criterion can change other criteria.</title>
          <p>Experiment:
 analyze the matrices in tensor  corresponding to different resilience criteria;
 build correlations between the results.</p>
        </sec>
        <sec id="sec-3-3-10">
          <title>Result – identification of interdependencies between criteria.</title>
          <p>7. System parameter optimization
9. Model validation on real data</p>
        </sec>
        <sec id="sec-3-3-11">
          <title>Objective – to assess how the system responds to prolonged periods of threat impact.</title>
          <p>Experiment:
 use a variable tensor  to model long-term or periodic threats;
 analyze changes in  over time.</p>
        </sec>
        <sec id="sec-3-3-12">
          <title>Result – forecasting the long-term resilience of the system.</title>
        </sec>
        <sec id="sec-3-3-13">
          <title>Objective – to compare the model's results with real-world data.</title>
          <p>Experiment:
 use empirical data to build  and  .</p>
          <p> compare the resulting  with actual performance indicators of systems.</p>
        </sec>
        <sec id="sec-3-3-14">
          <title>Result – validation of the model and its potential use for real systems.</title>
        </sec>
        <sec id="sec-3-3-15">
          <title>Objective – to determine optimal parameter values to reduce the impact of threats.</title>
          <p>Experiment:

use optimization algorithms to find values of  that maximize resilience  with
fixed  .</p>
        </sec>
        <sec id="sec-3-3-16">
          <title>Result – recommendations for improving the system.</title>
          <p>8. Modeling long-term consequences</p>
        </sec>
      </sec>
      <sec id="sec-3-4">
        <title>3.4. Example of using the model for the energy sector</title>
        <p>To apply the tensor model of critical infrastructure resilience to the energy sector, it is necessary to
define how each of the resilience criteria affects energy systems and determine the values for each
criterion and subsystem (e.g., energy networks, generation, and electricity transmission).</p>
        <p>We describe the resilience criteria of the model as follows:
 infrastructure functionality  – the ability of electrical networks and stations to perform their
functions after natural disasters or man-made accidents.
 recovery capability  – the time required to restore power supply after an accident or disaster.
 resilience to external threats  – the ability of energy systems to withstand natural disasters
(floods, snowstorms) or technological accidents.
 flexibility and adaptability  – the ability to adapt to changes in electricity demand or new
technologies, such as the integration of renewable energy sources.
 economic cost assessment  – the cost of restoring energy infrastructure after a disaster.
systems.
to energy crises.
integration with other systems</p>
        <p>– the impact of energy disruptions on other critical
infrastructures, such as transportation or utilities.
real-time analysis and forecasting  – the use of data to assess the current state of energy
flexibility of management structures  – the ability of management bodies to respond quickly
data security and protection  – protection of energy systems from cyberattacks.
environmental resilience</p>
        <p>– adaptation of energy systems to environmental requirements,
particularly reducing CO2 emissions.</p>
        <p>For each criterion (10 criteria), we have a 3x3 matrix, where each matrix represents a subsystem
at different stages. Therefore, the overall form of the tensor  will be as follows (1):</p>
        <sec id="sec-3-4-1">
          <title>Let us assume there are three main subsystems of energy infrastructure:  : energy generation;  : electricity transmission;  : electricity consumption (distribution and consumption).</title>
        </sec>
        <sec id="sec-3-4-2">
          <title>We will evaluate the resilience of the energy system at three stages:  : before the disaster (normal state);  : during the disaster (damage);  : after the disaster (recovery).</title>
          <p>where each  is a matrix that describes the corresponding criterion.</p>
          <p>In particular, for each  (2):
 =  , ,</p>
          <p>We have a three-dimensional structure where each element  is a matrix of size 3  × 3 and
represents a subsystem at different stages for each resilience criterion,
the first index  represents the resilience criterion (for  = 1,2, … ,10),
the second index  (1 – generation, 2 – transportation, 3 – consumption),
the third index  (1 – before the disaster, 2 – during the disaster, 3 – after the disaster).</p>
          <p>Let there be 4 threats that affect the system's resilience. Then, for each resilience criterion, we
have the following threat vector  , which reflects the impact of each threat on criterion  (3):

= (
… 
). (3)</p>
          <p>The result of the impact of threats on subsystem resilience can be represented by a tensor  ,
consisting of the corresponding matrices  , which contain the result of multiplying 
by the
corresponding threat element  . Thus, for each criterion  , a matrix of size 3  × 3 will be obtained,
where each element of this matrix is computed as (4):</p>
          <p>, , =  , , ×  , (4)</p>
          <p>, , is the element of the matrix for the  -th criterion, the  -th subsystem, and the  -th stage for
infrastructure functionality ( ):
recovery capability ( ):
resilience to external threats ( ):
for  : 
for  : 
for  : 
= [0.9,0.8,0.7,0.6],
= [0.85,0.75,0.65,0.55],
= [0.8,0.7,0.6,0.5].</p>
          <p>, , is the element of the matrix for the  -th criterion, the  -th subsystem, and the  -th stage.</p>
          <p>is the element of the threat vector for the  -th criterion and the  -th threat.</p>
          <p>The general form of the matrix  for each threat  is as follows (5):

allows assessing the resilience of the energy system to disasters by analyzing the impact of threats
on key resilience criteria. Let us have the following matrices  for three criteria:









</p>
        </sec>
        <sec id="sec-3-4-3">
          <title>For each resilience criterion  we calculate the matrices  for all threats  using formula (4).</title>
        </sec>
        <sec id="sec-3-4-4">
          <title>Below are a few examples:</title>
          <p>threat 1, criterion 1 (
Four main threats for the three criteria (
The results presented indicate the following:
resilience reduction during a disaster ( ):


</p>
          <p>0.7 ⋅ 0.85
= 0.6 ⋅ 0.85
0.4 ⋅ 0.85
0.6 ⋅ 0.85
0.55 ⋅ 0.85
0.3 ⋅ 0.85
0.5 ⋅ 0.85
0.5 ⋅ 0.85 =
0.2 ⋅ 0.85
for criterion  , the most vulnerable stages are in the transportation subsystem
( ) and consumption subsystem ( ).
for criterion  , the impact of the disaster reduces the ability for quick recovery,
particularly in the generation subsystem.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4. Discussions</title>
      <p>The results displayed on the heatmaps (Figures 1-9) provide crucial information about changes in
systems and threat levels at different stages of a disaster. Each heatmap shows the values of the
tensor SS for a specific stage of the disaster (before, during, after) for each criterion, such as
"Infrastructure Functionality," "Restoration Capability," and "Resilience to Threats." The color scale,
such as "seismic," allows for visualization of contrasts between high and low values. Warm colors
like red and orange may indicate high values or critical threat levels, while cool colors like blue and
purple represent low values or the absence of threats.</p>
      <p>The threat levels can have varying impacts on different subsystems, which is reflected in the
heatmap. Generally, higher threat levels lead to significant changes in the values of tensor SS,
indicating vulnerabilities in infrastructure or restoration capability. Different stages of the disaster
also have varying impacts on these indicators. In the pre-disaster stage, values may be relatively
stable, but weak points may already be identified that require attention. During the disaster stage,
tensor values can change dramatically, indicating a high level of threats and potential degradation
of system efficiency. After the disaster, the recovery or stabilization process may be visible, although
tensor values may remain high due to the long-term effects of the disaster (Figures 3, 6, 9).</p>
      <p>The heatmap also shows how each subsystem, such as generation, transportation, and
consumption, responds to different threat levels at various stages. For example, the "Transportation"
subsystem may be more vulnerable during the disaster, while "Generation" might show more stable
results before the disaster. It is important to compare the heatmaps for different disaster stages to
understand how system behavior changes over time. This helps identify trends, such as an increase
in system vulnerability at certain times, depending on the type of disaster and threat level.</p>
      <p>Overall, the heatmaps help visualize how various threat levels and disaster stages impact the
functionality of systems and subsystems, as well as indicate areas where improvements are necessary
to enhance resilience and infrastructure recovery.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Conclusions</title>
      <p>This paper examines the conceptual and practical aspects of ensuring critical infrastructure resilience
in an era of growing complexity and system interdependence. The proposed resilient critical
infrastructure model, based on tensor analysis, captures the multidimensional nature of
infrastructure, threat impacts, and subsystem dynamics across different operational stages.</p>
      <p>The model formalizes key resilience criteria, including functionality, recovery speed, adaptability,
economic efficiency, data security, and environmental sustainability. Tensor-based assessments
enable precise identification of vulnerabilities and the evaluation of threat impacts, particularly in
energy infrastructure.</p>
      <p>The findings highlight the model’s potential for risk monitoring, forecasting, and strategy
development to enhance infrastructure resilience. The approach is valuable for national security
agencies, engineers, and researchers in risk management. Future work will expand the model to
address intersectoral dependencies and assess the role of digitalization, AI, and blockchain in
strengthening adaptive capabilities.</p>
    </sec>
    <sec id="sec-6">
      <title>Declaration on Generative AI</title>
      <p>During the preparation of this work, the authors used X-GPT-4 in order to: Grammar and spelling
check. After using these tools/services, the authors reviewed and edited the content as needed and
take full responsibility for the publication’s content.</p>
      <p>References</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>S.</given-names>
            <surname>Argyroudis</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Mitoulis</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L.</given-names>
            <surname>Hofer</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Zanini</surname>
          </string-name>
          , E. Tubaldi, and
          <string-name>
            <given-names>D.</given-names>
            <surname>Frangopol</surname>
          </string-name>
          , “
          <article-title>Resilience assessment framework for critical infrastructure in a multi-hazard environment: Case study on transport assets.,” The Science of the total environment</article-title>
          , vol.
          <volume>714</volume>
          , p.
          <fpage>136854</fpage>
          ,
          <string-name>
            <surname>Jan</surname>
          </string-name>
          .
          <year>2020</year>
          , doi: 10.1016/j.scitotenv.
          <year>2020</year>
          .
          <volume>136854</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>B.</given-names>
            <surname>Wu</surname>
          </string-name>
          ,
          <string-name>
            <given-names>Z.</given-names>
            <surname>Tan</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Che</surname>
          </string-name>
          , and L. Cui, “
          <article-title>A Novel Resilience Assessment Framework for Multicomponent Critical Infrastructure,”</article-title>
          <source>IEEE Transactions on Engineering Management</source>
          , vol.
          <volume>71</volume>
          , pp.
          <fpage>14011</fpage>
          -
          <lpage>14031</lpage>
          ,
          <year>2024</year>
          , doi: 10.1109/TEM.
          <year>2024</year>
          .
          <volume>3438157</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>C.</given-names>
            <surname>Nan</surname>
          </string-name>
          and G. Sansavini, “
          <article-title>A quantitative method for assessing resilience of interdependent infrastructures,”</article-title>
          <string-name>
            <surname>Reliab. Eng. Syst. Saf.</surname>
          </string-name>
          , vol.
          <volume>157</volume>
          , pp.
          <fpage>35</fpage>
          -
          <lpage>53</lpage>
          ,
          <year>2017</year>
          , doi: 10.1016/j.ress.
          <year>2016</year>
          .
          <volume>08</volume>
          .013.
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4]
          <string-name>
            <given-names>H.</given-names>
            <surname>Alizadeh</surname>
          </string-name>
          and
          <string-name>
            <given-names>A.</given-names>
            <surname>Sharifi</surname>
          </string-name>
          , “
          <article-title>Assessing Resilience of Urban Critical Infrastructure Networks: A Case Study of Ahvaz</article-title>
          , Iran,” Sustainability, vol.
          <volume>12</volume>
          , p.
          <fpage>3691</fpage>
          , May
          <year>2020</year>
          , doi: 10.3390/su12093691.
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>R.</given-names>
            <surname>Francis</surname>
          </string-name>
          and
          <string-name>
            <given-names>B.</given-names>
            <surname>Bekera</surname>
          </string-name>
          , “
          <article-title>A metric and frameworks for resilience analysis of engineered and infrastructure systems</article-title>
          ,” Reliab. Eng. Syst. Saf., vol.
          <volume>121</volume>
          , pp.
          <fpage>90</fpage>
          -
          <lpage>103</lpage>
          ,
          <year>2014</year>
          , doi: 10.1016/j.ress.
          <year>2013</year>
          .
          <volume>07</volume>
          .004.
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <given-names>C.</given-names>
            <surname>Poulin</surname>
          </string-name>
          and
          <string-name>
            <given-names>M.</given-names>
            <surname>Kane</surname>
          </string-name>
          , “
          <article-title>The Effect of Time-Varying Value on Infrastructure Resilience Assessments,” IEEE Access</article-title>
          , vol.
          <volume>9</volume>
          , pp.
          <fpage>134556</fpage>
          -
          <lpage>134575</lpage>
          ,
          <year>2021</year>
          , doi: 10.1109/ACCESS.
          <year>2021</year>
          .
          <volume>3112944</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>M.</given-names>
            <surname>Panteli</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Mancarella</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Trakas</surname>
          </string-name>
          , E. Kyriakides, and
          <string-name>
            <given-names>N.</given-names>
            <surname>Hatziargyriou</surname>
          </string-name>
          , “
          <article-title>Metrics and Quantification of Operational and Infrastructure Resilience in Power Systems,”</article-title>
          <source>IEEE Transactions on Power Systems</source>
          , vol.
          <volume>32</volume>
          , pp.
          <fpage>4732</fpage>
          -
          <lpage>4742</lpage>
          , Feb.
          <year>2017</year>
          , doi: 10.1109/TPWRS.
          <year>2017</year>
          .
          <volume>2664141</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <given-names>D.</given-names>
            <surname>Rehak</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Senovsky</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Hromada</surname>
          </string-name>
          , and T. Loveček, “
          <article-title>Complex approach to assessing resilience of critical infrastructure elements,”</article-title>
          <string-name>
            <given-names>Int. J.</given-names>
            <surname>Crit</surname>
          </string-name>
          . Infrastructure Prot., vol.
          <volume>25</volume>
          , pp.
          <fpage>125</fpage>
          -
          <lpage>138</lpage>
          , Jun.
          <year>2019</year>
          , doi: 10.1016/J.IJCIP.
          <year>2019</year>
          .
          <volume>03</volume>
          .003.
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <given-names>D.</given-names>
            <surname>Reed</surname>
          </string-name>
          ,
          <string-name>
            <given-names>K.</given-names>
            <surname>Kapur</surname>
          </string-name>
          , and
          <string-name>
            <given-names>R.</given-names>
            <surname>Christie</surname>
          </string-name>
          , “
          <article-title>Methodology for Assessing the Resilience of Networked Infrastructure,” IEEE Systems Journal</article-title>
          , vol.
          <volume>3</volume>
          , pp.
          <fpage>174</fpage>
          -
          <lpage>180</lpage>
          , May
          <year>2009</year>
          , doi: 10.1109/JSYST.
          <year>2009</year>
          .
          <volume>2017396</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <given-names>D.</given-names>
            <surname>Alderson</surname>
          </string-name>
          , G. Brown, and W. Carlyle, “
          <article-title>Operational Models of Infrastructure Resilience,” Risk Analysis</article-title>
          , vol.
          <volume>35</volume>
          ,
          <string-name>
            <surname>Apr</surname>
          </string-name>
          .
          <year>2015</year>
          , doi: 10.1111/risa.12333.
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <given-names>H.</given-names>
            <surname>Raoufi</surname>
          </string-name>
          and
          <string-name>
            <given-names>V.</given-names>
            <surname>Vahidinasab</surname>
          </string-name>
          , “
          <article-title>Power system resilience assessment considering critical infrastructure resilience approaches and government policymaker criteria,” IET Generation, Transmission</article-title>
          &amp; Distribution, Jun.
          <year>2021</year>
          , doi: 10.1049/GTD2.12218.
        </mixed-citation>
      </ref>
      <ref id="ref12">
        <mixed-citation>
          [12]
          <string-name>
            <given-names>A.</given-names>
            <surname>Mottahedi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>F.</given-names>
            <surname>Sereshki</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Ataei</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Qarahasanlou</surname>
          </string-name>
          ,
          <article-title>and</article-title>
          <string-name>
            <given-names>A.</given-names>
            <surname>Barabadi</surname>
          </string-name>
          , “
          <article-title>Resilience estimation of critical infrastructure systems: Application of expert judgment,”</article-title>
          <string-name>
            <surname>Reliab. Eng. Syst. Saf.</surname>
          </string-name>
          , vol.
          <volume>215</volume>
          , p.
          <fpage>107849</fpage>
          ,
          <string-name>
            <surname>Jun</surname>
          </string-name>
          .
          <year>2021</year>
          , doi: 10.1016/J.RESS.
          <year>2021</year>
          .
          <volume>107849</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref13">
        <mixed-citation>
          [13]
          <string-name>
            <given-names>C.</given-names>
            <surname>Poulin</surname>
          </string-name>
          and
          <string-name>
            <given-names>M.</given-names>
            <surname>Kane</surname>
          </string-name>
          , “
          <article-title>Infrastructure Resilience Curves: Performance Measures and Summary Metrics,”</article-title>
          <string-name>
            <surname>Reliab. Eng. Syst. Saf.</surname>
          </string-name>
          , vol.
          <volume>216</volume>
          , p.
          <fpage>107926</fpage>
          ,
          <string-name>
            <surname>Jan</surname>
          </string-name>
          .
          <year>2021</year>
          , doi: 10.1016/j.ress.
          <year>2021</year>
          .
          <volume>107926</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref14">
        <mixed-citation>
          [14]
          <string-name>
            <given-names>E.</given-names>
            <surname>Vugrin</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Warren</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Ehlen</surname>
          </string-name>
          , and
          <string-name>
            <given-names>R.</given-names>
            <surname>Camphouse</surname>
          </string-name>
          , “
          <article-title>A Framework for Assessing the Resilience of Infrastructure and Economic Systems</article-title>
          ,” pp.
          <fpage>77</fpage>
          -
          <lpage>116</lpage>
          ,
          <year>2010</year>
          , doi: 10.1007/978-3-
          <fpage>642</fpage>
          -11405-
          <issue>2</issue>
          _
          <fpage>3</fpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref15">
        <mixed-citation>
          [15]
          <string-name>
            <given-names>A.</given-names>
            <surname>Shafieezadeh</surname>
          </string-name>
          and
          <string-name>
            <surname>L. I. Burden</surname>
          </string-name>
          , “
          <article-title>Scenario-based resilience assessment framework for critical infrastructure systems: Case study for seismic resilience of seaports,”</article-title>
          <string-name>
            <surname>Reliab. Eng. Syst. Saf.</surname>
          </string-name>
          , vol.
          <volume>132</volume>
          , pp.
          <fpage>207</fpage>
          -
          <lpage>219</lpage>
          , Dec.
          <year>2014</year>
          , doi: 10.1016/j.ress.
          <year>2014</year>
          .
          <volume>07</volume>
          .021.
        </mixed-citation>
      </ref>
      <ref id="ref16">
        <mixed-citation>
          [16]
          <string-name>
            <given-names>S.</given-names>
            <surname>Shin</surname>
          </string-name>
          et al.,
          <article-title>“A Systematic Review of Quantitative Resilience Measures for Water Infrastructure Systems</article-title>
          ,” Water, vol.
          <volume>10</volume>
          , p.
          <fpage>164</fpage>
          ,
          <string-name>
            <surname>Feb</surname>
          </string-name>
          .
          <year>2018</year>
          , doi: 10.3390/W10020164.
        </mixed-citation>
      </ref>
      <ref id="ref17">
        <mixed-citation>
          [17]
          <string-name>
            <given-names>J. F.</given-names>
            <surname>Hughes</surname>
          </string-name>
          and
          <string-name>
            <given-names>K.</given-names>
            <surname>Healy</surname>
          </string-name>
          , “
          <article-title>Measuring the resilience of transport infrastructure,” in Proc</article-title>
          .,
          <year>2014</year>
          . [Online]. Available: https://api.semanticscholar.org/CorpusID:106702067.
        </mixed-citation>
      </ref>
      <ref id="ref18">
        <mixed-citation>
          [18]
          <string-name>
            <given-names>X.-S.</given-names>
            <surname>Fu</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Hopton</surname>
          </string-name>
          , and
          <string-name>
            <given-names>X.</given-names>
            <surname>Wang</surname>
          </string-name>
          , “
          <article-title>Assessment of green infrastructure performance through an urban resilience lens</article-title>
          .,
          <source>” Journal of cleaner production</source>
          , vol.
          <volume>289</volume>
          ,
          <string-name>
            <surname>Nov</surname>
          </string-name>
          .
          <year>2020</year>
          , doi: 10.1016/j.jclepro.
          <year>2020</year>
          .
          <volume>125146</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref19">
        <mixed-citation>
          [19]
          <string-name>
            <given-names>D.</given-names>
            <surname>Rehak</surname>
          </string-name>
          , “
          <article-title>Assessing and strengthening organisational resilience in a critical infrastructure system: Case study of the Slovak Republic,” Safety Science</article-title>
          , vol.
          <volume>123</volume>
          , p.
          <fpage>104573</fpage>
          ,
          <string-name>
            <surname>Mar</surname>
          </string-name>
          .
          <year>2020</year>
          , doi: 10.1016/j.ssci.
          <year>2019</year>
          .
          <volume>104573</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref20">
        <mixed-citation>
          [20]
          <string-name>
            <given-names>A.</given-names>
            <surname>Sharifi</surname>
          </string-name>
          and
          <string-name>
            <given-names>Y.</given-names>
            <surname>Yamagata</surname>
          </string-name>
          , “
          <article-title>Principles and criteria for assessing urban energy resilience: A literature review,” Renewable &amp; Sustainable Energy Reviews</article-title>
          , vol.
          <volume>60</volume>
          , pp.
          <fpage>1654</fpage>
          -
          <lpage>1677</lpage>
          , Jul.
          <year>2016</year>
          , doi: 10.1016/J.RSER.
          <year>2016</year>
          .
          <volume>03</volume>
          .028.
        </mixed-citation>
      </ref>
      <ref id="ref21">
        <mixed-citation>
          [21]
          <string-name>
            <given-names>O.</given-names>
            <surname>Min</surname>
          </string-name>
          and
          <string-name>
            <given-names>L.</given-names>
            <surname>Dueñas-Osorio</surname>
          </string-name>
          , “
          <article-title>Time-dependent resilience assessment and improvement of urban infrastructure systems</article-title>
          .,” Chaos, vol.
          <volume>22</volume>
          3, p.
          <fpage>33122</fpage>
          ,
          <string-name>
            <surname>Aug</surname>
          </string-name>
          .
          <year>2012</year>
          , doi: 10.1063/1.4737204.
        </mixed-citation>
      </ref>
      <ref id="ref22">
        <mixed-citation>
          [22]
          <string-name>
            <given-names>D.</given-names>
            <surname>Kamissoko</surname>
          </string-name>
          et al.,
          <article-title>“Continuous and multidimensional assessment of resilience based on functionality analysis for interconnected systems</article-title>
          ,
          <source>” Structure and Infrastructure Engineering</source>
          , vol.
          <volume>15</volume>
          , pp.
          <fpage>427</fpage>
          -
          <lpage>442</lpage>
          , Dec.
          <year>2018</year>
          , doi: 10.1080/15732479.
          <year>2018</year>
          .
          <volume>1546327</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref23">
        <mixed-citation>
          [23]
          <string-name>
            <given-names>W.</given-names>
            <surname>Sun</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Bocchini</surname>
          </string-name>
          , and
          <string-name>
            <given-names>B.</given-names>
            <surname>Davison</surname>
          </string-name>
          , “
          <article-title>Resilience metrics and measurement methods for transportation infrastructure: the state of the art</article-title>
          ,
          <source>” Sustainable and Resilient Infrastructure</source>
          , vol.
          <volume>5</volume>
          , pp.
          <fpage>168</fpage>
          -
          <lpage>199</lpage>
          , May
          <year>2020</year>
          , doi: 10.1080/23789689.
          <year>2018</year>
          .
          <volume>1448663</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref24">
        <mixed-citation>
          [24]
          <string-name>
            <given-names>W.</given-names>
            <surname>Xu</surname>
          </string-name>
          ,
          <string-name>
            <given-names>J.</given-names>
            <surname>Cong</surname>
          </string-name>
          , and
          <string-name>
            <given-names>D.</given-names>
            <surname>Proverbs</surname>
          </string-name>
          , “
          <article-title>Evaluation of infrastructure resilience</article-title>
          ,”
          <source>International Journal of Building Pathology and Adaptation</source>
          , Jul.
          <year>2021</year>
          , doi: 10.1108/ijbpa-09-2020-0075.
        </mixed-citation>
      </ref>
      <ref id="ref25">
        <mixed-citation>
          [25]
          <string-name>
            <given-names>R.</given-names>
            <surname>Peculis</surname>
          </string-name>
          ,
          <string-name>
            <given-names>F.</given-names>
            <surname>Shirvani</surname>
          </string-name>
          , and
          <string-name>
            <given-names>P.</given-names>
            <surname>Perez</surname>
          </string-name>
          , “
          <article-title>Assessing Infrastructure System of Systems Integrity</article-title>
          ,”
          <year>2017</year>
          , doi: 10.36334/modsim.
          <year>2017</year>
          .f1.peculis.
        </mixed-citation>
      </ref>
      <ref id="ref26">
        <mixed-citation>
          [26]
          <string-name>
            <given-names>C.</given-names>
            <surname>Rochas</surname>
          </string-name>
          ,
          <string-name>
            <given-names>T.</given-names>
            <surname>Kuzņecova</surname>
          </string-name>
          , and
          <string-name>
            <given-names>F.</given-names>
            <surname>Romagnoli</surname>
          </string-name>
          , “
          <article-title>The concept of the system resilience within the infrastructure dimension: application to a Latvian case</article-title>
          ,
          <source>” Journal of Cleaner Production</source>
          , vol.
          <volume>88</volume>
          , pp.
          <fpage>358</fpage>
          -
          <lpage>368</lpage>
          , Feb.
          <year>2015</year>
          , doi: 10.1016/J.JCLEPRO.
          <year>2014</year>
          .
          <volume>04</volume>
          .081.
        </mixed-citation>
      </ref>
      <ref id="ref27">
        <mixed-citation>
          [27]
          <string-name>
            <given-names>L.</given-names>
            <surname>Wang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>X.</given-names>
            <surname>Xue</surname>
          </string-name>
          ,
          <string-name>
            <given-names>Z.</given-names>
            <surname>Wang</surname>
          </string-name>
          , and
          <string-name>
            <given-names>L.</given-names>
            <surname>Zhang</surname>
          </string-name>
          , “
          <article-title>A Unified Assessment Approach for Urban Infrastructure Sustainability</article-title>
          and Resilience,” Advances in Civil Engineering, Jul.
          <year>2018</year>
          , doi: 10.1155/
          <year>2018</year>
          /2073968.
        </mixed-citation>
      </ref>
      <ref id="ref28">
        <mixed-citation>
          [28]
          <string-name>
            <given-names>S.</given-names>
            <surname>Telenyk</surname>
          </string-name>
          ,
          <string-name>
            <given-names>O.</given-names>
            <surname>Rolick</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Bukasov</surname>
          </string-name>
          ,
          <string-name>
            <given-names>Y.</given-names>
            <surname>Dorogiy</surname>
          </string-name>
          ,
          <string-name>
            <given-names>D.</given-names>
            <surname>Halushko</surname>
          </string-name>
          and
          <string-name>
            <given-names>A.</given-names>
            <surname>Pysarenko</surname>
          </string-name>
          ,
          <article-title>"Qualitative evaluation method of IT-infrastructure elements functioning,"</article-title>
          <source>2014 IEEE International Black Sea Conference on Communications and Networking (BlackSeaCom)</source>
          , Odessa, Ukraine,
          <year>2014</year>
          , pp.
          <fpage>165</fpage>
          -
          <lpage>169</lpage>
          , doi: 10.1109/BlackSeaCom.
          <year>2014</year>
          .
          <volume>6849031</volume>
          .
        </mixed-citation>
      </ref>
      <ref id="ref29">
        <mixed-citation>
          [29]
          <string-name>
            <given-names>L.</given-names>
            <surname>Wang</surname>
          </string-name>
          ,
          <string-name>
            <given-names>X.</given-names>
            <surname>Xue</surname>
          </string-name>
          , and
          <string-name>
            <given-names>X.</given-names>
            <surname>Zhou</surname>
          </string-name>
          , “
          <article-title>A New Approach for Measuring the Resilience of Transport Infrastructure Networks</article-title>
          ,” Complex., vol.
          <year>2020</year>
          , pp.
          <fpage>7952309</fpage>
          -
          <lpage>7952309</lpage>
          , Aug.
          <year>2020</year>
          , doi: 10.1155/
          <year>2020</year>
          /7952309.
        </mixed-citation>
      </ref>
      <ref id="ref30">
        <mixed-citation>
          [30]
          <string-name>
            <given-names>O.</given-names>
            <surname>Min</surname>
          </string-name>
          and
          <string-name>
            <given-names>Z.</given-names>
            <surname>Wang</surname>
          </string-name>
          , “
          <article-title>Resilience assessment of interdependent infrastructure systems: With a focus on joint restoration modeling and analysis</article-title>
          ,
          <source>” Reliab. Eng. Syst. Saf.</source>
          , vol.
          <volume>141</volume>
          , pp.
          <fpage>74</fpage>
          -
          <lpage>82</lpage>
          , Sep.
          <year>2015</year>
          , doi: 10.1016/J.RESS.
          <year>2015</year>
          .
          <volume>03</volume>
          .011.
        </mixed-citation>
      </ref>
      <ref id="ref31">
        <mixed-citation>
          [31]
          <string-name>
            <given-names>J.</given-names>
            <surname>Kong</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Simonovic</surname>
          </string-name>
          , and
          <string-name>
            <given-names>C.</given-names>
            <surname>Zhang</surname>
          </string-name>
          , “
          <source>Resilience Assessment of Interdependent Infrastructure Systems: A Case Study Based on Different Response Strategies,” Sustainability</source>
          , vol.
          <volume>11</volume>
          , p.
          <fpage>6552</fpage>
          ,
          <string-name>
            <surname>Nov</surname>
          </string-name>
          .
          <year>2019</year>
          , doi: 10.3390/su11236552.
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>