A TRIZ Approach to Reliable Megaproject Sustainability

Purposes: This article presents a recent research into megaproject sustainability with a particular focus on identifying a structure of its body of knowledge so as to establish the methodology of megaproject assessment on sustainability (MAS), which consists of a research roadmap toward megaproject sustainability and a system reliability analysis. In response to the research topic on “Reviews for Advanced Construction Management” at Frontiers in Built Environment, this article aims to make a contribution with the description about a generic approach to conducting literature review based on a whole range of relevant evidence in a systemic way.Methodology: The research described in this article is underpinned by the use of several methods. The nine-square process (NSP) of Theory of Inventive Problem Solving (TRIZ) is the method for facilitating a systemic evidence-based learning (EBL) process to identify further research into MAS. A normal process to establish research roadmap was then introduced to summarize what has been identified as specific research tasks alongside lifecycle processes on megaproject delivery, to which RIBA Plan of Work 2020 was adopted as the prototype. An event tree analysis (ETA) was eventually introduced by incorporating the novel measurements on system reliability to support quantitative MAS in terms of both practices and research.Findings: This article presents several findings from the described research, and these include that the use of NSP led to the formation of a systematic procedure for literature review, a procedure to support MAS, a research roadmap to facilitate efforts to be made for megaproject sustainability, and the feasibility of system reliability analysis to measure the status of sustainability underpinned by research and practices throughout megaproject lifecycle.Implications: The described research provides four modules to foster further research into megaproject sustainability, and these include a TRIZ-based module to facilitate systemic literature review for EBL, a lifecycle process module for MAS, a prototype research roadmap to guide research and development for megaproject sustainability, and an ETA module to support a system reliability analysis in the dynamic process of research and practices toward megaproject sustainability.Value: The research described in this article has made an initial effort to conduct a strategic review, development, analysis, and discussion about tactics for research and development toward megaproject sustainability. Research findings can be used for related research and practices with regard to technical guidance and best practices in megaproject delivery.

SELECTION AND APPLICATION OF APPROPRIATE ANALYTICAL METHODS NEEDED TO ASSESS THE RISKS REDUCING THE SECURITY OF THE PROTECTED SYSTEM

Risk assessment is one of the prerequisites for understanding its causes and possible consequences. We base our risk assessment on the principles described in the European standard EN 31000 - Risk Management Process. This standard comprehensively describes the continuous activities that are necessary in managing risks and minimizing their possible adverse effects on the operation of the system under investigation. In this activity, it is necessary to first identify the existing risks, then analyze and evaluate the identified risks. In the analysis of existing risks, it is possible to use both qualitative and quantitative analytical methods, or combine them. We use qualitative methods in cases where we do not have a sufficient amount of input information, these are more subjective. Quantitative methods are more accurate, but also more demanding on input information and time. The choice of a suitable analytical method is a basic prerequisite for knowledge of risks and their evaluation. The values of individual risks obtained in this way are the basis for determining the measures that are necessary to minimize them, i.e., to adjust them to an acceptable level. The draft measures are always based on the value of the individual components used to calculate the risk number, as well as on the value of the asset , which needs to be protected. Appropriately chosen analytical methods are one of the basic prerequisites for the consistent application of the principles of risk management, as a continuous process aimed at increasing the overall security of the system under study. In the article, the author describes the procedures used in risk assessment, as well as specific analytical methods that can be used in working with risks. The aim of identifying risk factors is to create a list of events that could cause undesirable disruption to ongoing processes. At this stage, we define all the risks that will be subsequently analyzed and evaluated. When identifying, we can use methods such as, e.g. SWOT, PHA (Preliminary Hazard Analysis) or CA (Checklist Analysis). Methods suitable for determining the causes and creating scenarios for the course of a risk event are ETA (Event Tree Analysis) or FTA (Fault Tree Analysis). The basic analysis of the system can be performed using the FMEA method (Failure Mode and Effect Analysis), which provides a numerical risk assessment. By comparison with the numerical value of the risk that we are willing to accept, we obtain 2 groups of risks. Acceptable, which will be given regular attention and unacceptable, which we will focus on in risk management and we will try to minimize its negative affect on the functioning of the system under study.

Methodology for tunnel risk assessment using fault and event tree analysis

The intense demand and construction of tunnels is accompanied by uncertainties. The reason for appearance of uncertainties are the complex solutions and conditions for these structures. Location and dimensions are becoming more challenging, and the construction is predicted in complexed geological conditions, leading to application of new approaches, methodologies and technologies by the engineers. Most of the uncertainties and unwanted events in tunnelling occur in the construction phase, which generally leads to economic consequences and time losses. For easier handling of the uncertainties, they should be anticipated and studied within a separate part of each project. One of the newer approaches to dealing with uncertainties is hazard and risk assessment and defining ways to deal with them i.e. management. Hazards and risks can be analysed qualitatively and quantitatively. The quantitative analysis, examines the causes and consequences in more detail way and gives explanation of the dependencies. With the quantitative approach, a more valuable information for decision-making can be provided. There are various models and methods used for the quantification of hazards and risks. This paper presents a methodology in which the fault tree analysis and event tree analysis are used in combination to obtain quantitative results. The fault tree analysis is used for assessment of various hazards and the different ways and reasons that cause them. The event tree analysis is a method for assessing the possible scenarios, which follow after a certain hazard i.e. the consequences that may occur in the project. These trees represent graphic models combined with a mathematical (probabilistic) model, which give the probability of occurrence of the risks.

A Tutorial on Fire Domino Effect Modeling Using Bayesian Networks

High complexity and growing interdependencies of chemical and process facilities have made them increasingly vulnerable to domino effects. Domino effects, particularly fire dominoes, are spatial-temporal phenomena where not only the location of involved units, but also their temporal entailment in the accident chain matter. Spatial-temporal dependencies and uncertainties prevailing during domino effects, arising mainly from possible synergistic effects and randomness of potential events, restrict the use of conventional risk assessment techniques such as fault tree and event tree. Bayesian networks—a type of probabilistic network for reasoning under uncertainty—have proven to be a reliable and robust technique for the modeling and risk assessment of domino effects. In the present study, applications of Bayesian networks to modeling and safety assessment of domino effects in petroleum tank terminals has been demonstrated via some examples. The tutorial starts by illustrating the inefficacy of event tree analysis in domino effect modeling and then discusses the capabilities of Bayesian network and its derivatives such as dynamic Bayesian network and influence diagram. It is also discussed how noisy OR can be used to significantly reduce the complexity and number of conditional probabilities required for model establishment.

A Risk Assessment Framework Proposal Based on Bow-Tie Analysis for Medical Image Diagnosis Sharing within Telemedicine

The purpose of this paper is to propose a framework for cybersecurity risk management in telemedicine. The framework, which uses a bow-tie approach for medical image diagnosis sharing, allows the identification, analysis, and assessment of risks, considering the ISO/TS 13131:2014 recommendations. The bow-tie method combines fault tree analysis (FTA) and event tree analysis (ETA). The literature review supported the identification of the main causes and forms of control associated with cybersecurity risks in telemedicine. The main finding of this paper is that it is possible, through a structured model, to manage risks and avoid losses for everyone involved in the process of exchanging medical image information through telemedicine services. Through the framework, those responsible for the telemedicine services can identify potential risks in cybersecurity and act preventively, recognizing the causes even as, in a mitigating way, identifying viable controls and prioritizing investments. Despite the existence of many studies on cybersecurity, the paper provides theoretical contributions to studies on cybersecurity risks and features a new methodological approach, which incorporates both causes and consequences of the incident scenario.

Probabilistic Tephra Hazard Assessment of Campi Flegrei, Italy

<p>Campi Flegrei is an active volcano located in one of the most densely inhabited areas in Europe and under high-traffic air routes. There, the Vesuvius Observatory’s surveillance system, which continuously monitors volcanic seismicity, soil deformations and gas emissions, highlights some variations in the state of the volcanic activity. It is well known that fragmented magma injected into the atmosphere during an explosive volcanic eruption poses a threat to human lives and air-traffic. For this reason, powerful tools and computational resources to generate extensive and high-resolution hazard maps taking into account a wide spectrum of events, including those of low probability but high impact, are important to provide decision makers with quality information to develop short- and long- term emergency plans. To this end, in the framework of the Center of Excellence for Exascale in Solid Earth (ChEESE), we show the potential of HPC in Probabilistic Volcanic Hazard Assessment. On the one hand, using the ChEESE's flagship Fall3D numerical code and taking advance of the PRACE-awarded resources at CEA/TGCC-HPC facility in France, we perform thousands of simulations of tephra deposition and airborne ash concentration at different flight levels exploring the natural variability and uncertainty on the eruptive conditions on a 3D-grid covering a 2 km-resolution 2000 km x 2000 km computational domain. On the other hand, we create short- and long-term workflows, by updating current Bayesian-Event-Tree-Analysis-based prototype tools, to make them capable of analyze the large amount of information generated by the Fall3D simulations that finally gives rise to the hazard maps for Campi Flegrei.</p>

Towards a Semi-Quantitative Approach for Assessing Evacuation Scenarios in the Context of Popocatépetl Volcano, México—The Case of San Pedro Tlalmimilulpan

Volcanic exposure implies multiple hazards for human settlements. The identification of the potential hazards that volcanic activity can entail is a challenge requiring assessing the specific situations that a determined place would face. Popocatépetl, a volcano in the centre of México, represents a significant hazard source, and it is located within a densely populated region with more than 20 million people. Despite the existence of a colour-based volcano alert level system for the current activity of the volcano, it is relevant to assess which local scenarios are more likely depending on numerous variables, namely, related to the distance from the volcano. A semi-quantitative analysis was carried out based on existing hazard maps and considering the probability of occurrence of volcanic explosivity, taking the settlement of San Pedro Tlalmimilulpan as a case study. This analysis led to a hierarchised rank of hazards, providing a basis for analysing multiple scenarios through failure mode and event analysis, failure tree analysis and event tree analysis. This process facilitates the contextualisation of the multiple challenges and potential chains of events that emergency actions, namely, emergency evacuations, would face. The analysis of the critical paths can help to identify critical aspects that could hinder the post-event response.