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To reduce the flammability exposure assessment time and meet the requirements of airworthiness regulations of transport aircraft, inerting system has become the standard configuration of modern civil aircraft. Therefore, airworthiness regulations put forward definite quantitative index requirements for the safety of inerting system, and to obtain the quantitative data of the safety of inerting system, it is necessary to solve the calculation method. As one of the quantitative/qualitative evaluation techniques for system safety, fault tree analysis is recognized by international airworthiness organizations and national airworthiness certification agencies. When fault tree analysis technology is applied to quantitative analysis of the safety of inerted system, there are still some problems, such as heavy margin of constructing fault tree, great difficulty, high requirement for analysts and poor accuracy of solving when there are too many minimum cut sets. However, based on tens of thousands of flight simulation tests, Monte Carlo random number generation method can solve this problem.

In this paper, the fault tree of airborne inerting system is established, and the top event is airborne inerting system losing air separation function. Monte Carlo method based on random number generation is used to carry out system security analysis. The reliability of this method is verified.

The static fault tree analysis method based on Monte Carlo random number generation can not only solve the problem of quantitative analysis of inerting system, but can also avoid the defects of complicated solution and inaccurate solution caused by the large number of minimum cut sets, and its calculation results have good reliability.

The research results of this paper can be used as supporting evidence for airworthiness compliance of airborne inerting system.

The research results of this paper can provide practical guidance for the current civil airworthiness certification work.

Risk analysis is a critical investigation field for many sectors and organizations to maintain the information management reliable. Since mining is one of the riskiest sectors for both workers and management, comprehensive risk analysis should be carried out. The purpose of this paper is to explore comprehensively the undesired events that may occur during a particular process with their main reasons and to perform a risk analysis for these events, by developing a risk analysis methodology. For performing risk analysis, discovering and defining the potential accidents and incidents including their root causes are important contributions of the study as distinct from the related literature. The fuzzy approach is used substantially to obtain the important inferences about the hazardous process by identifying the critical risk points in the processes. In the scope of the study, the proposed methodology is applied to an underground chrome mine and obtaining significant findings of mining risky operations is targeted.

Fault tree analysis and fuzzy approach are used for performing the risk analysis. When determining the probability and the consequences of the events which are essential components for the risk analysis, expressions of the heterogeneous expert group are considered by means of the linguistic terms. Fault tree analysis and fuzzy approach present a quiet convenience solution together to specify the possible accidents and incidents in the particular process and determine the values for the basis risk components.

This study primarily presents a methodology for a comprehensive risk analysis. By implementing the proposed methodology to the underground loading and conveying processes of a chrome mine, 28 different undesired events that may occur during the processes are specified. By performing risk analysis for these events, it is established that the employee’s physical constraint while working with the shovel in the fore area, the falling of materials on employees from the chute and the scaling bar injuries are the riskiest undesired events in the underground loading and conveying process of the mine.

The proposed methodology provides a confidential and comprehensive method for risk analysis of the undesired events in a particular process. The capability of fault tree analysis for specifying the undesired events systematically and the applicability of fuzzy approach for converting the experts’ linguistic expressions to the mathematical values provide a significant advantage and convenience for the risk analysis.

The major contribution of this paper is to develop a methodology for the risk analysis of a variety of mining accidents and incidents. The proposed methodology can be applied to many production processes to investigate the dangerous operations comprehensively and find out the efficient management strategies. Before performing the risk analysis, determining the all possible accidents and incidents in the particular process using the fault tree analysis provides the effectiveness and the originality of the study. Also, using the fuzzy logic to find out the consequences of the events with experts’ linguistic expressions provides an efficient method for performing risk analysis.

A binary decision diagram (BDD) is a representation of Boolean functions that uses the notion of two‐way branching. It has long been used in the synthesis, simulation and testing of Boolean circuits, and has recently been adopted to solve fault tree models for both quantitative and qualitative reliability analyses. In this paper, the concept of binary decision diagram is first introduced. Then, a new method is proposed to analyze the reliability of fault tolerant systems using binary decision diagrams. Traditionally, such analyses are tackled by using fault trees based on cutsets. For complex models, an algorithm based on binary decision diagrams can shorten solution time dramatically. Experimental results are also presented to demonstrate the practicality and benefits of applying the proposed method in reliability analysis.

Presents a new qualitative fault tree evaluation algorithm based on bit manipulation techniques for the identification of the largest independent sub‐trees and the subsequent determination of all minimal cut sets of large and complex fault trees. The methodology developed is validated by direct application to a complex fault tree taken from the literature. Results obtained are compared with those available in the literature. Shows that the use of the algorithm (FTABMT) developed results in significant savings in both computer time and storage requirements.

This study aims to improve the reliability of emergency safety barriers by using the subjective safety analysis based on evidential reasoning theory in order to develop on a framework for optimizing the reliability of emergency safety barriers.

The emergency event tree analysis is combined with an interval type-2 fuzzy-set and analytic hierarchy process (AHP) method. In order to the quantitative data is not available, this study based on interval type2 fuzzy set theory, trapezoidal fuzzy numbers describe the expert's imprecise uncertainty about the fuzzy failure probability of emergency safety barriers related to the liquefied petroleum gas storage prevent. Fuzzy fault tree analysis and fuzzy ordered weighted average aggregation are used to address uncertainties in emergency safety barrier reliability assessment. In addition, a critical analysis and some corrective actions are suggested to identify weak points in emergency safety barriers. Therefore, a framework decisions are proposed to optimize and improve safety barrier reliability. Decision-making in this framework uses evidential reasoning theory to identify corrective actions that can optimize reliability based on subjective safety analysis.

A real case study of a liquefied petroleum gas storage in Algeria is presented to demonstrate the effectiveness of the proposed methodology. The results show that the proposed methodology provides the possibility to evaluate the values of the fuzzy failure probability of emergency safety barriers. In addition, the fuzzy failure probabilities using the fuzzy type-2 AHP method are the most reliable and accurate. As a result, the improved fault tree analysis can estimate uncertain expert opinion weights, identify and evaluate failure probability values for critical basic event. Therefore, suggestions for corrective measures to reduce the failure probability of the fire-fighting system are provided. The obtained results show that of the ten proposed corrective actions, the corrective action “use of periodic maintenance tests” prioritizes reliability, optimization and improvement of safety procedures.

This study helps to determine the safest and most reliable corrective measures to improve the reliability of safety barriers. In addition, it also helps to protect people inside and outside the company from all kinds of major industrial accidents. Among the limitations of this study is that the cost of corrective actions is not taken into account.

Our contribution is to propose an integrated approach that uses interval type-2 fuzzy sets and AHP method and emergency event tree analysis to handle uncertainty in the failure probability assessment of emergency safety barriers. In addition, the integration of fault tree analysis and fuzzy ordered averaging aggregation helps to improve the reliability of the fire-fighting system and optimize the corrective actions that can improve the safety practices in liquefied petroleum gas storage tanks.

This study aims to propose a tree‐based analytic tool that may be used in analyzing a large‐scale and complex service process. The tenet of this tool is based on the Boolean logic and named service tree analysis (STA). The proposed STA aims to reflect the customer participation perspective and to propose how to analyze the service process and deduce useful information.

Fault tree analysis is used as an underlying methodology since it has a Boolean logic to describe the customer's selection of each element and identifies critical events. Taking these advantages of the fault tree, the proposed STA consists of three main parts; service tree construction, qualitative analysis, and quantitative analysis. First, a service tree is constructed depending on how the service elements are selected by the customer; If the subordinate events are always selected by customers, they are linked with an AND gate, otherwise, with an OR gate. Next, in the qualitative analysis, service elements are characterized as core services, supporting services, and optional services by deducing a minimal service cut set. Last, qualitative analysis deals with deriving the impact of each service element based on the Kano model.

The suggested STA has advantages which help strategic operation and management of the service process.

This study is unique and even exploratory in that it first adopts the notion of tree analysis in structuring a large‐scale, complex service system. Further, the proposed service tree provides a systematic approach from customer participation perspective, which makes the service process to be managed efficiently.

Fault tree analysis (FTA) is a technique widely used in the study of the reliability of industrial systems and to quantify risks associated with potentially hazardous systems. Most of the studies carried out are related to how to construct a fault tree and how to carry out qualitative and quantitative analysis. However, this paper studies an approach for prioritisation and optimum resource allocation by making use of the FTA technique. The basic idea is to develop a simple procedure for the ranking of basic elements in the complex system, so that maximum increase in reliability can be achieved. We compare our approach with the existing basic event importance measures, and show that the simple approach is easy to apply and provides ranking that is similar to other more complicated approaches. In addition, the new ranking approach can be used at the initial stages of fault tree construction as it does not require the whole fault tree to be completely developed.

The purpose of this paper is to facilitate perishable product supply chain (PPSC) managers and practitioners to assess PPSC failure events. The paper proposed fault tree methodology for assessing failures associated with PPSC for evaluating the performance in terms of effective PPSC management adoption.

Initially, different failure events were identified from literature and semi-structured interviews from experts. Fault tree model was developed from the identified failure events. Probability of failure events was calculated using Poisson distribution based on the annual reports and interviews conducted from experts. Further, qualitative analysis – minimum cut sets (MCSs), structural importance coefficient (SIC) – and quantitative analysis – Birnbaum importance measure (BIM), criticality importance factor (CIF) and diagnosis importance factor (DIF) – were performed for ranking of failure events. In this study, fault tree development and analysis were conducted on apple supply chain to present the authenticity of this method for failure analysis.

The findings indicate that the failure events, given as failure at production and procurement (A2), that is, involvement of middleman (BE3), handling and packaging failure (BE4) and transportation failure (A3), hold the highest-ranking scores in analysis of PPSC using fault tree approach.

This research uses the modularization approach for evaluation of failure events of PPSC. This paper explores failures related to PPSC for efficient management initiatives in apple supply chain context. The paper also provides suggestion from managerial perspective with respect to each failure event.

This paper sets out to outline a human hazard analysis methodology as a tool for managing human error in aircraft maintenance, operations and production. The methodology developed has been used in a slightly modified form on Airbus aircraft programmes. This paper aims to outline a method for managing human error in the field of aircraft design, maintenance and operations. Undertaking the research was motivated by the fact that aviation incidents and accidents still show a high percentage of human‐factors events as key causal factors.

The methodology adopted takes traditional aspects of the aircraft design system safety process, particularly fault tree analysis, and couples them with a structured tabular notation called a human error modes and effects analysis (HEMEA). HEMEA provides data, obtained from domain knowledge, in‐service experience and known error modes, about likely human‐factors events that could cause critical failure modes identified in the fault tree analysis. In essence the fault tree identifies the failure modes, while the HEMEA shows what kind of human‐factors events could trigger the relevant failure.

The authors found that the methodology works very effectively, but that it is very dependent on locating the relevant expert judgement and domain knowledge..

The authors found that the methodology works very effectively, but that it is very dependent on locating the relevant expert judgement and domain knowledge. Using the method as a prototype, looking at aspects of a large aircraft fuel system, was very time‐consuming and the industry partner was concerned about the resource implications of implementing this process. Regarding future work, the researchers would like to explore how a knowledge management exercise might capture some of the domain knowledge to reduce the requirement for discursive, seminar‐type sessions with domain experts.

It was very clear that the sponsors and research partners in the aircraft industry were keen to use this method as part of the safety process. Airbus has used a modified form of the process on at least two programmes.

The authors are aware that the UK MOD uses fault tree analysis that includes human‐factors events. However, the researchers believe that the creation of the human error modes effects analysis is original. On the civil side of the aviation business this is the first time that human error issues have been included for systems other than the flightdeck. The research was clearly of major value to the UK Civil Aviation Authority and Airbus, who were the original sponsors.