Resilience assessment

  • 文章类型: Journal Article
    针对列控车载系统故障恢复后性能考核困难的问题,我们提出了一种使用可靠性作为系统弹性指标的弹性评估方法。由于系统故障与时间有关,采用离散时间贝叶斯网络方法获取系统失效前后的可靠性。随后,我们使用指数恢复模型来量化系统在恢复阶段的性能曲线,最后利用弹性三角形面积法对其弹性大小进行了量化。分析CTCS3-300T列控车载系统,我们发现,采用冷备冗余设计和热备冗余设计的系统的弹性分别为89.44%和87.34%,分别,表明与故障前级别相比,故障恢复后系统性能略有下降。当时,有必要根据实际情况调整运营计划,以避免对铁路网造成更大的影响。本文实现了故障恢复后的列控车载系统的性能弹性,为实现高速列车的智能维修提供理论参考。
    To address the problem of difficult performance assessment of train control on-board system after recovery from failures, we have proposed a resilience assessment methodology that uses reliability as an indicator of system resilience. Since the system failures are time-dependent, we adopted the Discrete Time Bayesian Network method to obtain the system\'s reliability before and after failure. Subsequently, we used an exponential recovery model to quantify the system\'s performance curve during the recovery phase, and finally utilized the resilient triangle area method to quantify its resilience size. Analyzing the CTCS3-300T train control on-board system, we found that the resilience of the system with cold standby redundancy design and hot standby redundancy design were 89.44 % and 87.34 %, respectively, indicating a slight decrease in system performance after recovery from failures compared to pre-failure levels. At that time, it was necessary to adjust operational plans based on actual conditions to avoid greater impact on the railway network. This paper realizes performance resilience of train control on-board system after failure recovery, which can be applied to similar systems and provide theoretical references for realizing intelligent maintenance of the high-speed train.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    城市排水系统的弹性评估是建设弹性城市的基本方面。最近,一些学者提出了全局弹性分析(GRA)方法,它根据不同系统故障场景的功能性能评估弹性。与传统的系统动力学方法相比,GRA方法考虑了内部结构失效对弹性的影响,但需要大量的计算。本研究提出了一种改进的GRA方法,通过减少系统场景仿真的数量来提高计算效率和实用性。首先,使用雨水管理模型(SWMM)和Python构建了海淀岛排水网络的水动力学模型。其次,利用聚类分析和收敛性分析对GRA方法进行了改进,以减少仿真场景。第三,通过系统功能功能建立了韧性评估指标,和两种类型的弹性增强措施,集中式和分布式,被提议。结果表明:(i)与传统的GRA方法相比,恢复力评估使计算效率提高了25%;(ii)在所有故障情况下,海淀岛内现有排水网络的恢复力指数均小于设计值(0.7),表明恢复能力水平较低;(Iii)与集中式策略相比,只有当系统故障水平低于9%时才有效,分布式策略增强了城市排水系统在较高故障级别(77%)的恢复能力。
    Resilience assessment for urban drainage systems is a fundamental aspect of building resilient cities. Recently, some scholars have proposed the Global Resilience Analysis (GRA) method, which assesses resilience based on the functional performance of different system failure scenarios. Compared to traditional system dynamics methods, the GRA method considers the impact of internal structural failure on resilience but requires a large amount of computation. This research proposed an improved GRA method to enhance computational efficiency and practicality by reducing the number of system scenario simulations. Firstly, a hydrodynamic model of the drainage network of Haidian Island has been constructed using the Storm Water Management Model (SWMM) and Python. Secondly, the GRA method was improved using cluster analysis and convergence analysis to reduce the simulation scenarios. Thirdly, a resilience assessment index was established through system function functions, and two types of resilience enhancement measures, centralized and distributed, were proposed. The results show: (i) resilience assessment increases the computational efficiency by 25% compared to the traditional GRA method; (ii) the resilience index of the existing drainage network within Haidian Island is less than the design value (0.7) in all failure scenarios, indicating a lower level of recovery capability; (iii) compared to the centralized strategy, which is only effective when the system failure level is less than 9%, the distributed strategy enhances the resilience of the urban drainage system at a higher failure level (77%).
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    传统的无人机群体评估指标缺乏对系统遭受攻击后性能变化的全过程描述。为了满足无人机集群系统日益增长的弹性要求的现实需求,在本文中,研究了无人机群自组织网络的建模和弹性评估方法。首先,基于复杂网络理论,构建了考虑通信层和结构层的双层耦合无人机群网络模型。然后,三个网络拓扑指标,即,平均节点度,平均聚类因子,和平均网络效率,用于表征无人机群体复原力指标。最后,无人机群体复原力评估方法,考虑到动态进化,实现了无人机群在多场景下不同策略下的恢复力评估。仿真实验表明,无人机群体恢复能力评估,考虑动态重构,与网络结构设计有很强的相关性。
    The traditional UAV swarm assessment indicator lacks the whole process description of the performance change after the system is attacked. To meet the realistic demand of increasing resilience requirements for UAV swarm systems, in this paper, we study the modeling and resilience assessment methods of UAV swarm self-organized networks. First, based on complex network theory, a double layer coupled UAV swarm network model considering the communication layer and the structure layer is constructed. Then, three network topological indicators, namely, the average node degree, the average clustering factor, and the average network efficiency, are used to characterize the UAV swarm resilience indicators. Finally, the UAV swarm resilience assessment method, considering dynamic evolution, is designed to realize the resilience assessment of the UAV swarm under different strategies in multiple scenarios. The simulation experiments show that the UAV swarm resilience assessment, considering dynamic reconfiguration, has a strong correlation with the network structure design.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    强大而有弹性的氮(N)流系统可以有效地确保一致的食品生产和消费活动,同时保持环境质量。在这项研究中,我们构建了一个指标体系来评估包括粮食生产和消费在内的N流量系统的弹性,1998年至2018年在青藏高原(QTP)的县尺度上。随后探讨了子系统耦合协调度(CCD)和N损失对N流系统弹性的影响。结果表明,尽管从1998年到2018年,整个N流系统的弹性仍然很低,并且表现出时空差异,但超过90%的县经历了改善。高弹性地区(>0.15)主要集中在四川省部分县,其中N损失与系统弹性呈正相关。复原力的水平取决于农业和畜牧业的发展,在这个地区,子系统的CCD也很高(>0.5),最平衡的环境和社会经济发展。系统弹性较低的地区集中在QTP的东部,人类活动造成了巨大的干扰。农牧系统的碎片化加上粮食生产和驱动压力子系统的系统弹性低,导致子系统之间的CCD低。相比之下,西部地区,以稳定的粮食生产系统为特征,高粮食自给自足,对外部系统的依赖较弱,表现出更高的系统复原力和抵抗力。我们的研究结果为QTP农牧区粮食生产和消费的N资源管理和政策制定提供了参考。
    A robust and resilient nitrogen (N) flow system can effectively ensure consistent food production and consumption activities while preserving environmental quality. In this study, we constructed an indicator system to evaluate N flow system resilience including food production and consumption, at the county scale on the Qinghai-Tibet Plateau (QTP) from 1998 to 2018. The subsystem coupling coordination degree (CCD) and the effect of N losses on N flow system resilience were subsequently explored. The results indicated that despite the overall N flow system resilience remaining low and exhibiting spatiotemporal disparities from 1998 to 2018, over 90 % of the counties experienced improvements. High resilience areas (>0.15) were mainly concentrated in some counties in Sichuan Province, where N losses were positively correlated with system resilience. The level of resilience depended on agricultural and livestock development, and the CCD of subsystems was also high (>0.5) in this region, with the most balanced environmental and socioeconomic development. The low system resilience areas were concentrated in the eastern part of the QTP, where human activities caused substantial disturbances. The fragmentation of the agro-pastoral system coupled with the low system resilience of the food production and driving pressure subsystems led to low CCD between subsystems. In contrast, the western regions, characterized by a stable food production system, high food self-sufficiency, and weak dependence on external systems, showed a higher degree of system resilience and resistance. Our findings provide a reference for N resource management and policy formulation for food production and consumption in the agricultural and pastoral areas of the QTP.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Review
    背景:冠状病毒大流行对护理的组织和提供产生了深远的影响。医疗机构在应对大流行方面面临的挑战加剧了人们对复原力概念的兴趣。虽然努力已经进入了韧性的概念化,关于如何评估组织弹性的工作相对较少。本文报道了对实证医疗保健研究中韧性测量和评估方法的广泛回顾,并检查它们对研究人员的有用性,政策制定者和医疗保健经理。
    方法:各种数据库(MEDLINE,EMBASE,PsycINFO,CINAHL(EBSCO主机),CochraneCENTRAL(Wiley),CDSR,科学引文索引,和社会科学引文索引)从2000年1月到2021年9月进行了搜索。我们包括定量的,定性和建模研究,重点是衡量或定性评估医疗保健背景下的组织弹性。所有研究都是根据标题筛选的,摘要和全文。对于每种方法,关于测量或评估格式的信息,数据收集和分析方法,并提取了其他相关信息。我们将组织弹性的方法分为五个对比主题领域:(1)冲击类型;(2)弹性阶段;(3)包括特征或指标;(4)产出的性质;(5)目的。在这些主题领域中对这些方法进行了叙述性总结。
    结果:35项研究符合纳入标准。我们发现在如何评估医疗保健中的组织弹性方面缺乏共识,应该测量或评估什么,什么时候,以及使用什么弹性特征和指标。测量和评估方法的范围各不相同,格式,内容和目的。方法不同,无论是前瞻性(休克前的弹性)还是回顾性(休克期间或休克后),以及它们在多大程度上解决了一套预先定义的和特定于冲击的特征和指标。
    结论:已经开发了一系列具有不同特征和指标的方法来评估医疗保健中的组织弹性,可能对研究人员有价值,政策制定者和医疗保健经理。在实践中使用的方法的选择应取决于冲击的类型,评估的目的,结果的预期用途,以及数据和资源的可用性。
    BACKGROUND: The coronavirus pandemic has had a profound impact on organization and delivery of care. The challenges faced by healthcare organizations in dealing with the pandemic have intensified interest in the concept of resilience. While effort has gone into conceptualising resilience, there has been relatively little work on how to evaluate organizational resilience. This paper reports on an extensive review of approaches to resilience measurement and assessment in empirical healthcare studies, and examines their usefulness for researchers, policymakers and healthcare managers.
    METHODS: Various databases (MEDLINE, EMBASE, PsycINFO, CINAHL (EBSCO host), Cochrane CENTRAL (Wiley), CDSR, Science Citation Index, and Social Science Citation Index) were searched from January 2000 to September 2021. We included quantitative, qualitative and modelling studies that focused on measuring or qualitatively assessing organizational resilience in a healthcare context. All studies were screened based on titles, abstracts and full text. For each approach, information on the format of measurement or assessment, method of data collection and analysis, and other relevant information were extracted. We classified the approaches to organizational resilience into five thematic areas of contrast: (1) type of shock; (2) stage of resilience; (3) included characteristics or indicators; (4) nature of output; and (5) purpose. The approaches were summarised narratively within these thematic areas.
    RESULTS: Thirty-five studies met the inclusion criteria. We identified a lack of consensus on how to evaluate organizational resilience in healthcare, what should be measured or assessed and when, and using what resilience characteristic and indicators. The measurement and assessment approaches varied in scope, format, content and purpose. Approaches varied in terms of whether they were prospective (resilience pre-shock) or retrospective (during or post-shock), and the extent to which they addressed a pre-defined and shock-specific set of characteristics and indicators.
    CONCLUSIONS: A range of approaches with differing characteristics and indicators has been developed to evaluate organizational resilience in healthcare, and may be of value to researchers, policymakers and healthcare managers. The choice of an approach to use in practice should be determined by the type of shock, the purpose of the evaluation, the intended use of results, and the availability of data and resources.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    网络物理系统(CPS)由计算和通信核心监视和控制。该网络层可以更好地管理受控子系统,但它也给CPS的安全和保护带来了威胁,最近的网络攻击证明了这一点。由此产生的对网络安全的治理和政策强调在学术界得到了大量文献的反映。在这篇文章中,我们将现有的CPS分析知识系统化。具体来说,我们专注于对中断发生前后的CPS进行定量评估。通过对文献中采用的模型和方法的系统分析,我们开发了一个由三个步骤组成的CPS弹性评估框架,即,(1)CPS说明,(2)中断情景识别,(3)韧性策略选择。对于框架的每个步骤,我们提出了CPS分析的既定方法,并提出了方法选择的四个标准.该框架提出了一个标准化的工作流程来评估CPS在发生中断之前和之后的弹性。参考变电站和相关的通信网络来举例说明所提出的框架的应用。案例研究表明,拟议的框架通过量化实施弹性策略的效果来支持弹性决策。
    Cyber-physical systems (CPSs) are monitored and controlled by a computing and communicating core. This cyber layer enables better management of the controlled subsystem, but it also introduces threats to the security and protection of CPSs, as demonstrated by recent cyberattacks. The resulting governance and policy emphasis on cybersecurity is reflected in the academia by a vast body of literature. In this article, we systematize existing knowledge on CPS analysis. Specifically, we focus on the quantitative assessment of CPSs before and after the occurrence of a disruption. Through the systematic analysis of the models and methods adopted in the literature, we develop a CPS resilience assessment framework consisting of three steps, namely, (1) CPS description, (2) disruption scenario identification, and (3) resilience strategy selection. For each step of the framework, we suggest established methods for CPS analysis and suggest four criteria for method selection. The framework proposes a standardized workflow to assess the resilience of CPSs before and after the occurrence of a disruption. The application of the proposed framework is exemplified with reference to a power substation and associated communication network.The case study shows that the proposed framework supports resilience decision making by quantifying the effects of the implementation of resilience strategies.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    相互依赖的基础设施系统容易受到随机故障和自然灾害导致的故障的级联影响。在这项工作中提供的数据是处理后的数据用于拟议的弹性评估框架的相互依存的水和运输网络处理两种类型的故障[1]。案例研究是坦帕的水和运输的互连网络,佛罗里达随机故障的数据是从开发的算法框架以及美国人口普查数据集提供的土地利用和社会脆弱性数据中获得的。然后,我们使用这些生成的数据的子集来构建网络对随机故障的弹性的预测模型。至于自然灾害的情景,我们在2017年关注了飓风伊尔玛,因为它直接影响了佛罗里达州的重点地区。我们使用了这次飓风的具体指南和原始洪水数据,由FEMA提供,估算每个地理区域(多边形)和相关网络组件的积水。根据估计的水位,我们将这些区域标记为失败和未损坏。最后,我们使用这些数据来开发地理空间地理加权回归(GWR)模型来预测每个多边形的弹性。我们提供了水和交通网络的最终数据集,以促进选定城市地区未来任何弹性研究的可重用性。
    Interdependent infrastructure systems are vulnerable to the cascading effect of failures resulting from random failures and natural disasters. The data provided in this work is the processed data used for the proposed resilience assessment framework for interdependent water and transportation networks dealing with both types of failure [1]. The case study is the interconnected networks of water and transportation in Tampa, Florida. The data for the random failure is obtained from the developed algorithmic framework and the land use and social vulnerability data provided by the U.S. Census datasets. We then used a subset of this produced data to construct predictive models for the network resilience to random failures. As for the natural disaster scenario, we focused on hurricane Irma in 2017 as it directly affected the focused region in Florida. We used the specific guidelines and the raw flooding data for this hurricane, provided by FEMA, to estimate the standing water for each geographical area (polygons) and the associated network components. We labeled the areas as failed and undamaged based on the estimated water levels. Finally, we used this data for developing a geospatial Geographical Weighted Regression (GWR) model to predict the resilience in each polygon. We present the final dataset for water and transportation networks to facilitate reusability for any future resilience study in the selected urban area.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    The quality of the environment as well as public health is convincingly coupled with the functioning of a power subsector. The power subsector plays a pivotal role in the sense that it emerges as the key cross-sectional element for the society\'s functioning (production, services, healthcare, education and others). A modern society consists of infrastructure systems that are primarily dependent on continuous electricity supplies. Each and every element of the electric power infrastructure is unique, and thus, its malfunction can disrupt the functioning of an important part of the electric power infrastructure. In conjunction with ensuring the functioning of electric power infrastructure, our attention must be drawn to the resilience issue. As far as the resilience of electric power infrastructure is concerned, it can resist weather-related events ensuring there are no disruptions in continuous electricity supplies. First, in the introductory part, the article presents the legal framework in the Slovak Republic. Second, it describes the current state of the electric power infrastructure of Slovakia. Third, it handles the state of the level of security risk assessment. Later on, in the literature review, besides turning to the issue of resilience assessment, the authors focused on the area of resilience of power engineering. Furthermore, the article scrutinizes resilience assessment in Slovakia, and it briefly examines approaches towards natural threats. In addition, the article demonstrates several approaches towards flood resilience. Having used different methods, the primary concern is to devise a framework for resilience assessment. Therefore, the included case study examines aspects of the proposed framework for resilience assessment. In conclusion, our aim was, in most respects, to outline an innovative methodological framework for increasing the resilience of electricity infrastructure.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

       PDF(Pubmed)

  • 文章类型: Journal Article
    Natural disasters and human-made disasters are threatening urban areas globally. The resilience capacity of the urban system plays an important role in disaster risk response and recovery. Strengthening urban disaster resilience is also fundamental to ensuring sustainable development. Various practices and research for enhancing urban disaster resilience have been carried out worldwide but are yet to be reviewed. Accordingly, this paper gives a scientometric review of urban disaster resilience research by using CiteSpace. The time span (January 2001-January 2021) was selected and divided into three phases based on the number of publications. In addition, according to keyword statistics and clustering results, the collected articles are grouped into four hotspot topics: disaster risk reduction, specific disaster resilience research, resilience assessment, and combination research. The results show that most of the existing research is in the first two categories, and articles in the second and fourth categories both show a high growth rate and could be further research directions. The review indicates that urban disaster resilience is essential for a city\'s sustainable development. Moreover, the findings provide scholars a full picture of the existing urban disaster resilience research which can help them identify promising research directions. The findings can also help urban government officials and policymakers review current urban disaster management strategies and make further improvements.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

       PDF(Pubmed)

  • 文章类型: Journal Article
    Climate change is causing the decline of coral reef ecosystems globally. Recent research highlights the importance of reducing CO2 emissions in combination with implementing local management actions to support reef health and recovery, particularly actions that protect sites which are more resilient to extreme events. Resilience assessments quantify the ecological, social, and environmental context of reefs through the lens of resilience, i.e., the capacity of a system to absorb or withstand stressors such that the system maintains its structure and functions and has the capacity to adapt to future disturbances and changes. Resilience assessments are an important tool to help marine managers and decision makers anticipate changes, identify areas with high survival prospects, and prioritize management actions to support resilience. While being widely implemented, however, there has not yet been an evaluation of whether resilience assessments have informed coral reef management. Here, we assess the primary and gray literature and input from coral reef managers to map where resilience assessments have been conducted. We explore if and how they have been used to inform management actions and provide recommendations for improving the likelihood that resilience assessments will result in management actions and positive conservation outcomes. These recommendations are applicable to other ecosystems in which resilience assessments are applied and will become increasingly important as climate impacts intensify and reduce the window of opportunity for protecting natural ecosystems.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Sci-hub)

公众号