Event Tree Analysis Method Research Articles

An experimental study into the fault recognition of onboard systems by navigational officers

Autonomy has allowed the maritime industry to design integrated systems leading to the concept of maritime autonomous surface ships. As research towards autonomous operations increases seafarers must be equipped with the knowledge of how to react to onboard system faults and threats to the safety of crew, vessel and cargo. Consequently, the maritime industry may utilise bridge simulators to train seafarers in autonomous operations. By integrating simulation into navigational officer training, it is possible to aid the development of seafarers fault recognition patterns. Moreover, simulation training can provide seafarers with the knowledge to be proactive in fault finding over reactive. Therefore, this study is conducted in a navigational simulator and investigates the fault recognition patterns of seafarers during realistic watch conditions with alternative tasks i.e. paperwork. Moreover, a novel Event Tree Analysis method is proposed to analyse the performance of seafarers and effectiveness of human machine relationship. The study found a low percentage of candidates successfully reacted to all faults and without additional alarms the vessel may have resulted in further danger. Applying the methodology and data assimilated from the study could aid the development of navigational officer short courses, developing seafarers behavioural skills which complement their technical talents.

Evaluation of M&A Risk Based on Adaptive Immune Genetic Algorithm

In order to improve the convergence and accuracy of M&A risk assessment method, an M&A risk assessment method based on adaptive immune genetic algorithm is proposed. The risk of M&A is divided into M&A preparation stage, M&A implementation stage, and M&A integration stage. The event tree analysis method is used to clarify the inducement of M&A risk events. We optimize the traditional genetic algorithm, design adaptive immune genetic algorithm to ensure the convergence of risk assessment algorithm, select the risk assessment indicators of enterprise M&A, determine the weight of the assessment indicators, and construct the quantitative model of enterprise M&A risk assessment. The experimental results show that the proposed risk assessment method takes less time, has higher accuracy, and has less probability of enterprise data imbalance.

Research on Abnormal Event Classification of Expressway Tunnel based on Security Control

Based on the perspective of tunnel traffic safety operation and control and the human, vehicle, road, and environment system in tunnel operation process, adopting event tree analysis method according to the different influencing factors, generation mechanism and performance characteristics of tunnel abnormal events, this research propose abnormal event classification tree diagram. According to the current abnormal event management and control mechanism in China, the administration departments and disposal facilities associated with different types of abnormal events in expressway tunnel operation are sorted out, which can provide decision-making support for the rapid treatment of abnormal events and realize intelligent control of tunnel.

Research on Online Verification of Relay Protection Setting Value Based on Multi-source Information Fusion Technology and Bow-tie Model

In view of the complexity and flexibility of the current power grid, in order to make relay protection online verification more accurate and effective, a protection importance degree sequence assessment method based on the multi-source information fusion technology and bowtie model is proposed. Firstly, the cause of incorrect protection actions is analyzed by establishing a fault tree through multi-source information fusion technology, and the event tree analysis method is used to deduce the final development result of the event. Combined with the fault tree and the event tree, a bow-tie model is formed to visually and completely describe the whole process of the event. Then the economic loss of the event is analyzed as the basis for assessing the protection importance degree, and the online inspection of the protection setting value is completed from high to low according to the importance degree sequence. Finally, the IEEE 3-machine 9-bus system is used to verify the correctness and rationality of the method through simulation.

Assessment, Mitigation, and Control of Potential Gas Leakage in Existing Buildings Not Designed for Gas Installation in Indonesia

Operational activities of gas pipelines are associated with potential hazards and risks that can potentially lead to pipeline failure, including failure of the gas distribution pipeline in existing buildings. Unfortunately, few studies on risk analysis of the gas distribution pipeline in existing buildings have been published. Therefore, this study was conducted to provide a reference for analyzing the risk of pipeline leakage caused by small-scale leakage, large-scale gas release, and gas pipeline rupture in existing buildings in Indonesia not designed for gas installation. The study was performed using the event tree analysis method. The methodology of this study was initiated by identifying the scenario of the case of small-scale leakage, large-scale gas release, or gas pipeline rupture. Then, pivotal events were identified, an event tree diagram was constructed, the event failure of each pivotal event was determined, and the probability value of the outcome risk was calculated. The risk was evaluated in terms of fire, casualties, and gas released. The results of this study showed the highest risk in each scenario which can result in fire, severe casualties, and light poisoning. The highest risk in the small-scale leak scenario had a probability value of 1.5 × 10−3. In the large-scale gas release scenario, the highest risk had a probability value to incur a fireball, severe casualties, and light gas poisoning of 6.0 × 10−4. In the gas pipeline rupture scenario, the highest risk had a probability value of fireball, severe casualties, and light poisoning of 7.0 × 10−4. The probability value of each risk was reduced by the installation of a gas detector and water sprinkler as a barrier.

Risk Analysis of Earth-Rock Dam Failures Based on Fuzzy Event Tree Method.

Earth-rock dams make up a large proportion of the dams in China, and their failures can induce great risks. In this paper, the risks associated with earth-rock dam failure are analyzed from two aspects: the probability of a dam failure and the resulting life loss. An event tree analysis method based on fuzzy set theory is proposed to calculate the dam failure probability. The life loss associated with dam failure is summarized and refined to be suitable for Chinese dams from previous studies. The proposed method and model are applied to one reservoir dam in Jiangxi province. Both engineering and non-engineering measures are proposed to reduce the risk. The risk analysis of the dam failure has essential significance for reducing dam failure probability and improving dam risk management level.

The application of event tree analysis in a work accident at maintenance operations

Event tree analysis is an inductive method, which involves determining the events flowing from the failure of a component or part of the system. Starting from an initiator event or an origin failure, the event tree analysis allows the estimation of system deviation, taking into account in a systematic manner the functioning or failure of detection devices, alarm, prevention, protection or intervention. This paper follows the steps in determining the causes that led to a work accident through the Event Tree Analysis method. The construction of event tree analysis consists of graphical representation of operations which through a succession of decisions lead to an accident during maintenance of work equipment.

Risk analysis in case of fire on PZL BRYZA using the event tree analysis / Analiza ryzyka w przypadku pożaru samolotu PZL BRYZA z wykorzystaniem metody drzewa zdarzeń

Abstract The paper presents application of the Event Tree Analysis method for analyzing risk in complex situations. A model associated with the occurrence of fire on PZL Bryza was developed using the aircraft flight manual. The probabilities of events caused by the initiating event and the losses caused by each of the highlighted final undesirable events were determined. Statistical data for flight safety was used to calculate probability of the initiating event. The risk was determined as the probability that losses of at least given category will occur during one flight. As a result of the conducted analysis it was found that the probability of in-flight fire is very small. However, in such a case, the probability of death of one or more passengers is relatively high.

A-SMGCS 기능 위험 평가 사례 연구

Safety assessment is necessary to develop safety related CNS/ATM system. It includes functional hazard assessment (FHA), effects eliciting system safety requirement that mitigates system`s hazardous event. This paper performs a case study for functional hazard assessment of A-SMGCS. To do this, related A-SMGCS studies from Eurocontrol and EMMA are surveyed, and assessment schemes of functional hazard from Eurocontrol and EMMA are combined. Not only FHA scope but also several assumptions for FHA are defined for Incheon airport. 29 hazards are identified and their severities are assessed. And exposures and safety objectives from hazards are analyzed using event tree analysis method. Differences between result of this study and result of EMMA are analysed, and assessment results in this study are also reviewed.

Risk Assessment on the Transition Program for Air Traffic Control Automation System Upgrade

We analyzed the safety risks of the transition program for Air Traffic Control (ATC) automation system upgrade by using the event tree analysis method in this paper. We decomposed the occurrence progress of the three transition phase and built the event trees corresponding to the three stages, and then we determined the probability of success of each factor and calculated probability of success of the air traffic control automation system upgrade transition. In the conclusion, we illustrate the transition program safety risk according to the results.

Impact Analysis of Human Errors on Operation Reliability in Power System

Based on modification of CREAM extended method, an approach is proposed to calculate the human error probability suitable to power system situation and an operation reliability assessment model is firstly put forward. Then the event tree analysis method is introduced to analyze the impact of human error on operation reliability. Simulation results of IEEE-RTS79 demonstrate that human error makes a significant impact on the operation reliability.

海難審判庁の裁決録をもとにしたイベントツリーを用いた油流出と人身事故の分析

Today, 1350 ship collision incidents occur in Japan in one year. This means that four collisions occur every day. Thesecases not only risked the loss of human life, but also developed into serious oil spills. Oil spill from ships can cause veryserious on the financial and environmental damage, as well.Causes of these incidents are investigated and it is usually concluded, from the psychological and medical viewpoints, tobe operator error. After those incidents, it is very important to perform research for developing and improving safetydevices or systems and for understanding recurrence of incidents. An Event Tree Analysis method of compoundingmaritime incidents, especially those including oil spill and casualties after a collision is introduced.

Evaluation of hazards associated with hydrogen storage facilities

The scope of this paper is to highlight common hazards arising from hydrogen storage and distribution systems, as well as to reveal potential accidents that hydrogen may yield under certain conditions. Hazard analysis performed was based on the Event Tree Analysis Method and examined the final outcomes of an accidental hydrogen release. The output of this analysis was that hydrogen may lead to a series of accident types that can pose a severe threat for property and public safety. Moreover, computational estimation of the dispersion resulting from liquefied hydrogen spills showed that the resulting cloud behaves as a heavy rather than a light gas, remaining in flammable concentrations at low heights above the ground and increasing, therefore, substantially the risk for accidental fires and explosions.

영국철도시스템에 적용된 리스크평가 사례

The British railway safety research group has developed a risk assessment model for the railway infrastructure and major railway accidents. The major hazardous factors of the railway infrastructure were identified and classified in the model. The frequency rates of critical top events were predicted by the fault tree analysis method using failure data of the railway system components and ratings of railway maintenance experts, The consequences of critical top events were predicted by the event tree analysis method. They classified the Joss of accident due to railway system into personal. commercial and environmental damages. They also classified 110 hazardous event due to railway system into three categories. train accident. movement accident and non-movement accident. The risk assessment model of the British railway system has been designed to take full account of both the high frequency low consequence type events (events occurring routinely for which there is significant quantity of recorded data) and the low frequency high consequence events (events occurring rarely for which there is little recorded data). The results for each hazardous event were presented in terms of the frequency of occurrence (number of events/year) and the risk (number of equivalent fatalities per year).