Resilience Assessment Methodology Research Articles

Fast Resilience Assessment of Distribution Systems With a Non-Simulation-Based Method

Traditional simulation-based method for resilience assessment of distribution systems is very time consuming since the network topology is characterized with a large number of scenario-specific optimization models. In this paper, we propose a methodology for fast resilience assessment of distribution systems with a non-simulation-based method, which can significantly improve the assessment accuracy and computational efficiency. First, a probabilistic metric is proposed to assess the system resilience against extreme events, which quantifies the system performance starting from the pre-event stage to the post-event stage. Then, a mixed-integer linear programming (MILP) is proposed to model the energization paths (EPs) with binary decision variables. Subsequently, the resilience metric-related probability events are built using the EPs. Last, the probabilistic resilience metric is explicitly expressed based on the total probability formula, conditional probability formula and EP-topology simplification methods. In the proposed method, the topology evolution along with the system degradation, restoration (part healed) and recovery (all healed) is characterized with a non-simulation-based method, rather than the multiple scenarios in traditional methods. The numerical tests validate the effectiveness of the proposed method and superiority over the simulation-based approach.

Assessing flood resilience of urban drainage system based on a ‘do-nothing’ benchmark

To deal with the threat of urban flooding, it is necessary to assess the flood resilience of urban drainage systems at the planning and design stage. This study proposes a system resilience assessment methodology based on a ‘do-nothing’ benchmark. In this new benchmark, the number of flooded nodes used in computation of mean flood duration in the system is that observed under a ‘do-nothing’ scenario (i.e. with no intervention), irrespective of the scenario under evaluation. This methodology is demonstrated using a case study in Chizhou city, China, a simple stormwater drainage network with seven subcatchments. Schemes of interventions (with distributed storage tanks) that aim to mitigate flooding are then produced by zero-one integer programming and schemes sampling. The results show that the proposed method can compute the mean flood duration and system resilience reasonably and helps identify effective intervention schemes. Compared with traditional methods, this resilience assessment method based on a ‘do-nothing’ scenario can correctly indicate the change in trend of system resilience provided by different schemes, and aids understanding of different interventions to improve system resilience to urban flooding. This study also provides a new way to test different interventions and to explore which provide the greatest improvement in system resilience.

Optimal Restoration Strategy Based on Resilience Improvement for Power Transmission Systems Under Extreme Weather Events

In the past few years, extreme weather events have threatened operations of power systems. The improvement of resilience for power system becomes crucial. This paper proposes an optimal restoration strategy, considering the resilience index of power transmission systems in restoration processes. Firstly, a typhoon is taken as an example to establish an extreme weather event impact model to obtain the failure probability of lines. Then Monte Carlo method is used to generate fault sets. For each restoration time point, the optimal restoration model is used to acquire the maximum recovery loads. The resilience index of system can be obtained by the resilience assessment methodology during restoration. Finally, the proposed strategy is compared with distance-based strategy in IEEE 6-bus system, which demonstrates the superiority of the proposed strategy.

A resilience assessment simulation tool for distribution gas networks

Energy networks, especially the ones of natural gas, electric energy and district heating, are crucial infrastructures for the everyday life of our countries and cities. Thus, resilience and security of networks are becoming increasingly critical issues due to: a) the vulnerability of the territories, b) the effects of climate change (e.g. landslides, floods) and/or natural events (e.g. heartquakes) and c) cyber and terrorist attacks. In recent years, more attention has been paid to transmission networks rather than to urban distribution ones, although important consequences in terms of economic and public health damages can arise for urban distribution networks too.In this paper, the authors propose a resilience assessment methodology for natural gas distribution networks. The methodology allows simulating fault conditions in the network leading to quality of service issues (e.g. methane dispersion in the atmosphere, prolonged service interruption) and to disservices (e.g. disrupted final users). In such way, it could be possible to define effective operational management strategies to reduce the risk of service disruption and to increase the network resilience evaluating structural network improvement measures. The proposed methodology has been experimented in a case study of a real distribution network and the results show it is possible to avoid or minimize the risk of service.

Assessing Urban Resilience in Complex and Dynamic Systems: The RESCCUE Project Approach in Lisbon Research Site

Urban environments are challenged with unprecedented anthropogenic and natural pressures, the latter being accelerated by the growing awareness of the consequences of climate change. The concept of urban resilience has been growing in response, since it allows us to understand city behaviour as a system of systems, improving its response to extreme climate-related events. This paper presents the EU H2020 Resilience to Cope with Climate Change in Urban Areas (RESCCUE) project approach in Lisbon’s research site, regarding the Hazur® resilience assessment methodology. This methodology focuses on the interdependencies between services and infrastructures, and on the recovery times needed to restore its normal functionalities. This approach allows the integration of several work packages of the RESCCUE project, from climate change projections to adaptation strategies selection. The assessment was conducted for 19 services and 146 infrastructures, including water (supply and drainage systems), power, mobility, waste, telecommunication, environment, and the social sector. The principal climate-related hazard analysed at the Lisbon research site was urban flooding. The main result consists of a deep understanding of the relations between different services and the consequent cascade effects triggered by flooding events. Stakeholders’ involvement, beyond the project consortium, was fundamental for the success of the methodology implementation.

Quantification of the Benefits for Power System of Resilience Boosting Measures

Severe natural events leading to wide and intense impacts on power systems are becoming more and more frequent due to climate changes. Operators are urged to set up plans to assess the possible consequences of such events, in view of counteracting them. To this aim, the application of the resilience concept can be beneficial. The paper describes a methodology for power system resilience assessment and enhancement, aimed at quantifying both system resilience indicators evaluated for severe threats, and the benefits to resilience brought by operational and grid hardening measures. The capabilities of the methodology are demonstrated on real study cases.

After the hurricane: Validating a resilience assessment methodology

With increasing utility grid outages in the United States, there is growing interest in assessing risk and developing mitigation strategies to reduce the impact of grid outages. Working with the U.S. Air Force, the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) developed a replicable energy resilience assessment methodology and investment decision tool to: (1) identify and score hazards and vulnerabilities at the site level; (2) analyze risks to energy infrastructure; and (3) identify and prioritize energy resilience investments. This work improves on existing resilience assessment methodologies and tools by combining a bottom-up, all-hazards assessment methodology with top-down geographic information system mapping capabilities to provide an innovative, dynamic tool for identifying and prioritizing actionable solutions. This process combines probabilistic forecasting with an iterative approach for continuously updating and reassessing risks to address temporal dynamism. Relationships among systems are modeled and visualized to estimate the effectiveness of resilience actions across multiple interdependent systems and inform financial priorities through cost-difficulty-impact trade-offs. The approach is validated in a case study at Tyndall Air Force Base (AFB) in Florida, which experienced a Category 5 hurricane in 2018. The risks and mitigation strategies identified pre-hurricane are compared with post-hurricane, realized impacts. The assessment effectively identifies risks and actions to increase site energy resilience, but the methodology can be enhanced though greater consideration of the interdependencies between the energy system and related systems like transportation, communication, and food/water systems, which impact the recovery of the energy system and the base.

Tackling the “New Normal”: A Resilience Assessment Method Applied to Real-World Urban Water Systems

The water sector is, currently and for the foreseeable future, challenged by rising levels of uncertainty in demand and availability of water, in a context of aging infrastructure and limited investment. In order to support strategic planning, water companies need a way to assess how their system behaves when faced with a range of changing conditions (climatic trends, asset deterioration, behavioral patterns, etc.) as well as accidents/incidents and/or extreme events (wildcards). In this study, a resilience assessment methodology was demonstrated, with ‘stress tests’ alternative water system configurations (including systems designed with decentralized or distributed philosophies) under a range of scenarios and extreme events. A ‘resilience profile graph’ was developed to quantify the performance of each configuration. The methodology was applied to the real-world urban water system of Oasen, which supplies the eastern part of the Province of South Holland, where the current system configuration and two potential future configurations were tested (one decentralized and one distributed). We show how the concept of resilience, operationalized through this methodology, can assist long term decision making and support strategic infrastructure planning.

Resilience modeling of engineering systems using dynamic object-oriented Bayesian network approach

Resilience is defined as the ability of a system to efficiently recover from a disruptive event. For an engineered system, it is dependent on the system performance and time. In this study, a new resilience assessment methodology is proposed. The methodology considers an engineered system to be characterized with three resilience capacities of absorption, adaptation, and restoration. These capacities are modeled as a function of time using dynamic object-oriented Bayesian network formalism. The application of the methodology is demonstrated using the Fukushima Daiichi nuclear power accident. The analysis showed that the adaptive capacity contributed most to the system resilience, followed by the absorptive capacity and the restorative capacity. The applicability of the proposed formalism has demonstrated that the concept of resilience is highly valuable for engineering design, operation, and emergency planning.

Resilience of coastal communities to climate change in Bangladesh: Research gaps and future directions

Abstract The assessment of resilience for people, places, and systems to climate-change hazards is essential for understanding how to reduce disaster risks. Globally, a number of resilience assessment methodologies have been developed and implemented by a variety of entities, including national and local organizations, donor agencies, and academic researchers. In Bangladesh, although a number of resilience studies have been conducted, it has never been determined whether these assessments rightfully addressed conceptual understanding, methodological approaches, and disciplinary underpinnings, and maintained compliance with on-going research communications standards. To unpack this gap, we systematically reviewed 38 articles to characterize how the resilience to climate change, of coastal communities in Bangladesh, is being assessed. To operationalize the study, we have presented a brief overview of the assessment tools and then applied an analytical framework containing six criteria: comprehensiveness of dimensions, scalar relationships, temporal dynamism, addressing uncertainties of climate change by modeling and scenario-making, participatory approaches, and action plans. The overview analysis shows diverse traditions of methodological underpinnings, and reveals authors' often incomplete conceptual understandings of resilience. Results of the review analysis reveal extensive inadequacy regarding multiple dimensionality, scalar and temporal scales, and more importantly, addressing the uncertainty of climate change. In relation to comprehensiveness, current literature has failed to consistently comply with global research communication in regard to the criteria of institutional and infrastructural dimensions. More attention needs to be placed on temporal and scalar dynamics. Most importantly, the uncertainty issue is virtually overlooked in the literature, and iterative processes and the development of alternate states of planning through scenario analysis are also critical, for risk reduction and adaptation to climate-change impacts. Substantial emphasis should be given to include all possible stakeholders in the planning and implementation of any climate-change adaptation or mitigation program.

Towards a More Resilient Delhi: Rapid Urbanization and Climate Change

The discourse on resilient cities encapsulates various analogies, which are further constructed through the work of researchers in creation of several resilience assessment methodologies and toolkits. Despite the presence of numerous resilience assessment tools, there is an apparent lack of participation of residents of the global south within the assessment and iterative transformation processes. The situation, hence, is not truly represented through application of these tools in certain socio-political climates such as of India. Consistent economic growth of India has resulted in rapid urbanization of major cities. But, this has not been supplemented with proper planning, resulting in imbalances in all spheres of city infrastructure. Delhi, capital city of India, has been one of the worst hit cities. The hot seasons have caused thousands of fatalities in the past few years. An attempt is made to review the application of current resilience tools in Delhi against the backdrop of the sustainable development goals. In an attempt to improve the approach of these existing tools, an initial iteration is conducted, hinging on qualitative data obtained through surveying a sample population of the city and accessible quantitative metric data. Possible intervention scenarios are further suggested in view of aforementioned stressors and resilience scores. Research question: Where are the current resilience tools found lacking in the case of the global south, specifically in Delhi? How can the applicability of these tools be improved without compromising the deliverables yet ensuring an all-inclusive approach? Key findings: (1) The city is found lacking in adequate infrastructure facilities to its residents especially within the ambits of basic water and sanitation provision and healthcare services. (2) The city is relatively unprepared to face unforeseen events, both at the administrative and the grassroots levels. The lack of knowledge transfer and cooperation are largely evident.

Socio-Environmental Vulnerability Mapping for Environmental and Flood Resilience Assessment: The Case of Ageing and Poverty in the City of Wrocław, Poland.

The phenomena of urbanization and climate change interact with the growing number of older people living in cities. One of the effects of climate change is an increased riverine flooding hazard, and when floods occur this has a severe impact on human lives and comes with vast economic losses. Flood resilience management procedures should be supported by a combination of complex social and environmental vulnerability assessments. Therefore, new methodologies and tools should be developed for this purpose. One way to achieve such inclusive procedures is by incorporating a social vulnerability evaluation methodology for environmental and flood resilience assessment. These are illustrated for application in the Polish city of Wrocław. Socio-environmental vulnerability mapping, based on spatial analyses using the poverty risk index, data on the ageing population, as well as the distribution of the areas vulnerable to floods, was conducted with use of a location intelligence system combining Geographic Information System (GIS) and Business Intelligence (BI) tools. The new methodology allows for the identification of areas populated by social groups that are particularly vulnerable to the negative effects of flooding. Integr Environ Assess Manag 2018;14:592-597. © 2018 SETAC.

Ecosystem services-based composite indicator for assessing community resilience to floods

Disaster resilience studies have acknowledged the role of the natural environment in reinforcing community resilience; however, pragmatic environmental indicators are lacking, particularly geospatial composite indicators. This paper aims to introduce a composite environmental indicator for assessing community resilience to floods, targeting regional-scale geospatial applications. The composite indicator has been built on conceptualized inter-relationships between Ecosystem Services (ESs) and community resilience. The environmental parameters used to measure the composite were identified by surveying the cross-disciplinary literature from the domains of ESs and disaster resilience. The application of the composite indicator was demonstrated by a case study in Colombo, Sri Lanka. The composite indicator was tested on flood declaration and community response data from Colombo. The application employed a Weighted Linear Combination Method (WLCM) and was executed in a Geographic Information System (GIS)-based platform. The geospatial data for application and validation were collected through secondary sources. The developed composite indicator consists of four proxy indicators (i.e., soil hydraulic properties, slope, land use, and a precipitation factor) and parameters used to measure them. The parameters were also derived from the conceptualized relationship that elaborates ESs into a bundle of services, including flood regulation, climate regulation, and nutrient recycling, whereas many of the existing resilience assessment methodologies focused only on flood regulation. Furthermore, the composite indicator organized the environmental parameters into two tiers, facilitating a range of users. Hence, incorporating this ESs-based composite indicator into existing resilience assessment methodologies could guide community resilience-building initiatives towards more sustainable outcomes.

Sustainability of integrated energy systems: A performance-based resilience assessment methodology

One of the key elements of any community or facility is the integrated energy system (IES) which consists of utility power plants, distributed generation systems, and building heating and cooling systems. Assessing the sustainability of an IES would be of great value to decision-making relevant to design, future growth planning, and operation of such systems. This paper addresses one of the basic issues in this regard, i.e. resilience assessment and quantification of IES. A new performance-based method for characterizing and assessing resilience of multi-functional demand-side engineered systems is proposed in this study. Through modeling of system response to potential internal and external failures (called failure modes) during different operational temporal periods (such as different diurnal and seasonal periods of the year), the proposed methodology quantifies resilience of the system based upon loss in the services which the system is designed to deliver. A three-dimensional matrix, called Loss Matrix, is introduced whose elements represent the undelivered system services under different scenarios, i.e. combinations of failure modes and different operational temporal periods. Assigning monetary penalty costs to such losses and including them in the objective function of an optimization model of the entire system allows the three-dimension loss matrix to be reframed into a two-dimensional Consequence Matrix where individual elements represent the imposed penalty costs to the system stakeholders due to undelivered services and/or non-optimal system performance. Normalizing the individual elements results in the Resilience Matrix of the system for different scenarios. The developed methodology is illustrated for IES of a large office building serves to satisfy critical and noncritical electrical, heating, and cooling loads. The resilience assessment framework proposed in this paper would serve as a mean to identify critical components of a particular IES, thereby facilitating resilient design and operation, and also to evaluate cost-effective resilience enhancement strategies.

Three-module Power System Resilience Assessment Framework under Different Types of Disasters

With the frequent occurrence of natural disasters and the increasing of terrorism, the study of power system resilience has attracted extensive attention. Based on the three stages of the development of different disasters: pre-disaster, during-disaster and post-disaster, this paper proposes a complete assessment framework of power system resilience. It defines the toughness of power system under various types of disasters, the losses caused by disaster, the response ability of power system, the recovery ability and some other concepts or indices, in order to reflect the levels of power system resilience synthetically. IEEE RTS 79 system is tested to verify the effectiveness of the proposed assessment framework. The new framework can measure the robustness and power restoration ability of power system under various disasters, making up the shortcomings of existing resilience assessment methodologies.

Power System Resilience to Extreme Weather: Fragility Modeling, Probabilistic Impact Assessment, and Adaptation Measures

Historical electrical disturbances highlight the impact of extreme weather on power system resilience. Even though the occurrence of such events is rare, the severity of their potential impact calls for 1) developing suitable resilience assessment techniques to capture their impacts and 2) assessing relevant strategies to mitigate them. This paper aims to provide fundamentals insights on the modeling and quantification of power systems resilience. Specifically, a fragility model of individual components and then of the whole transmission system is built for mapping the real-time impact of severe weather, with focus on wind events, on their failure probabilities. A probabilistic multitemporal and multiregional resilience assessment methodology, based on optimal power flow and sequential Monte Carlo simulation, is then introduced, allowing the assessment of the spatiotemporal impact of a windstorm moving across a transmission network. Different risk-based resilience enhancement (or adaptation) measures are evaluated, which are driven by the resilience achievement worth index of the individual transmission components. The methodology is demonstrated using a test version of the Great Britain's system. As key outputs, the results demonstrate how, by using a mix of infrastructure and operational indices, it is possible to effectively quantify system resilience to extreme weather, identify and prioritize critical network sections, whose criticality depends on the weather intensity, and assess the technical benefits of different adaptation measures to enhance resilience.

Avaliação da Resiliência como ferramenta para entender a fronteira amazônica como um sistema socioecológico

Este artigo apresenta o pensamento de resiliência e uma metodologia para avaliação desta que consisteem definir o sistema (pergunta-chave e limites do sistema no tempo e no espaço); olhando paraa história (linha do tempo, fatores desencadeantes e interações entre escalas); especificando a resiliência“do que” e “contra que” (definição de atributos e variáveis); cenários (prováveis fatores desencadeantesfuturos e possíveis regimes futuros desejáveis e indesejáveis); e desenvolvimento deconsiderações de gestão para promover cenários desejáveis. A avaliação de resiliência de três grandesgrupos sociais do município de Cotriguaçu em Mato Grosso, Brasil ”“ proprietários de terras médias egrandes, os povos indígenas Rikbaktsa e agricultores familiares ”“ revelou que cada grupo social passoupor várias iterações do ciclo adaptativo (crescimento-colapso-reorganização), e que a dinâmica dessesistema é em grande parte determinada por fatores econômicos e políticos que vêm de uma escala maior. Contribuições para a metodologia de avaliação de resiliência incluem basear a análise do sistemaem sua trajetória histórica, procurar incorporar explicitamente as perspectivas dos atores locais, eusar a análise de cenários para desenvolver possíveis intervenções de gestão.

Multiple-Hazard Fragility and Restoration Models of Highway Bridges for Regional Risk and Resilience Assessment in the United States: State-of-the-Art Review

AbstractHighway bridges are one of the most vulnerable constituents of transportation networks when exposed to one or more natural hazards, such as earthquakes, hurricanes, tsunamis, and riverine floods. To facilitate and enhance prehazard and posthazard event mitigation and emergency response strategies of transportation systems and entire communities, probabilistic risk and resilience assessment methodologies have attracted increased attention recently. In this context, fragility and restoration models for highway bridges subjected to a range of hazards are essential tools for efficient and accurate quantification of risk and resilience. This paper provides a comprehensive review of state-of-the-art fragility and restoration models for typical highway bridge classes that are applicable for implementation in multihazard risk and resilience analyses of regional portfolios or transportation networks in the United States. An overview of key gaps in the literature is also presented to guide future research.

A critical review of selected tools for assessing community resilience

The concept of resilience is increasingly used in academic and policy circles. To operationalize this concept and reduce the ambiguities surrounding it, since the turn of the century, various resilience assessment methodologies have been introduced. This paper provides a critical review of 36 selected community resilience assessment tools. These tools have been developed by a variety of entities, including national and local organizations, international donor organizations, and academic researchers. First, an overview of the selected tools is presented. This overview analysis shows that while some commonalities exist, there are also considerable differences between the tools. Next, based on literature review, an analytical framework is developed that identifies six criteria for evaluating performance of resilience assessment tools. These are, namely, addressing multiple dimensions of resilience, accounting for cross-scale relationships, capturing temporal dynamism, addressing uncertainties, employing participatory approaches, and developing action plans. Results show that limited success has been achieved in addressing these criteria. In terms of comprehensiveness, the environmental dimension has received relatively less attention in spite of its significance for building community resilience. Further improvements are needed to account for dynamics over time and across space. More attention to employing iterative processes that involve scenario-based planning is needed to better address challenges associated with uncertainties. Results also show that more attention needs to be paid to stakeholder participation in developing assessment tools. The paper concludes by highlighting several other areas of weakness that need to be addressed and discussing major challenges that still remain.

Mapping and assessing coastal resilience in the Caribbean region

Assessing the vulnerability and resilience to coastal hazards is a critical worldwide issue, especially for hurricane-prone coastal regions such as the Caribbean. However, the development of a useful metric for vulnerability and resilience assessment has a lot of challenges. Cartography and GIS analysis can contribute effectively to the solution of the issue by integrating natural and human data layers for assessment, mapping, and visualization. This paper uses the new Resilience Inference Measurement (RIM) model to assess the resilience of 25 countries in the Caribbean region to hurricanes. The RIM indices of the countries were computed using three variables representing three dimensions: exposure, damage, and recovery, and eight variables representing social-environmental capacity. The RIM resilience indices were mapped and compared with the vulnerability indices computed in a previous study. The results show that Turks & Caicos Islands had the highest resilience, whereas Montserrat had the lowest. This paper contributes to the hazard literature by demonstrating new vulnerability and resilience assessment methodologies that include validation and enable inference. The paper also contributes to the cartography and GIS literature by demonstrating the need to integrate data and perspectives from multiple disciplines and regions, as well as the ability of geospatial technology, in producing useful decision-making tools for a very pressing societal problem.