1354 Words6 Pages

This paper presents a Fault Tree (FT) based approach for quantitative risk analysis in the construction industry that can take into account both types of uncertainties including objective and subjective uncertainty. In this research, the identified basic events are first categorized based on the availability of historical data into probabilistic and possibilistic. The probabilistic and possibilistic events are represented by probability distributions and fuzzy numbers, respectively. The hybrid uncertainty analysis is then performed through combination of Monte Carlo simulation and fuzzy set theory. The probability of occurrence of top event is finally calculated using the proposed fault tree based hybrid uncertainty analysis method. The efficiency*…show more content…*

In construction industry, several researches have been conducted in the area of QRA using*…show more content…*

The proposed approach accounts for both types of uncertainties (i.e., probabilistic and possibilistic) as well as the interdependencies that exist among different events. The flowchart diagram of different stages of quantitative FTA using the proposed hybrid uncertainty analysis method is depicted in Fig. 1. As shown in this figure, in the first step the objectives of analysis using FT are identified. The top event is identified and the scope of FTA is defined in the second and third steps. In the fourth step, the root causes of top event are investigated and the basic events leading to the occurrence of top event are recognized. Then, the identified basic events are categorized based on the availability of historical data into probabilistic and possibilistic. The probabilistic and possibilistic events are represented by objective and subjective probability, respectively. Then, the fault scenarios leading to the occurrence of top event are identified by constructing the FT structure. The hybrid uncertainty analysis is performed through combination of Monte Carlo simulation and fuzzy set theory which is explained in detail in section 3 of this paper. The probability of occurrence of top event is now calculated using the proposed fault tree based hybrid uncertainty analysis method. Finally, by calculating the importance measure of each fault scenario, the response strategies can be adopted by manager for

In construction industry, several researches have been conducted in the area of QRA using

The proposed approach accounts for both types of uncertainties (i.e., probabilistic and possibilistic) as well as the interdependencies that exist among different events. The flowchart diagram of different stages of quantitative FTA using the proposed hybrid uncertainty analysis method is depicted in Fig. 1. As shown in this figure, in the first step the objectives of analysis using FT are identified. The top event is identified and the scope of FTA is defined in the second and third steps. In the fourth step, the root causes of top event are investigated and the basic events leading to the occurrence of top event are recognized. Then, the identified basic events are categorized based on the availability of historical data into probabilistic and possibilistic. The probabilistic and possibilistic events are represented by objective and subjective probability, respectively. Then, the fault scenarios leading to the occurrence of top event are identified by constructing the FT structure. The hybrid uncertainty analysis is performed through combination of Monte Carlo simulation and fuzzy set theory which is explained in detail in section 3 of this paper. The probability of occurrence of top event is now calculated using the proposed fault tree based hybrid uncertainty analysis method. Finally, by calculating the importance measure of each fault scenario, the response strategies can be adopted by manager for

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## Fault Tree Analysis Methodology

2358 Words | 10 PagesIt is a deductive methodology that is it involves reasoning from the general to the specific, working backwards through time to examine preceding events leading to failure. FTA is used for determining the potential causes of incidents, or for system failures more generally. The safety engineering discipline uses this method to determine failure probabilities in quantitative risk assessments. A fault tree is a graphic model that displays the various logical combinations of failures that can result in an incident, as shown in figure given below. These combinations may include equipment failures, human errors and management system failures.

## Bonhuetter Ferguson Case Study

1253 Words | 6 PagesThe Bonhuetter-Ferguson Method: [18]This is a Bayesian technique, meaning it incorporates the independently derived prior estimates of the overall expected losses with the estimates generated in a similar matrix as the BCL method. To use the Bonhuetter –Fergusson method one must take the expected loss ratio and expected past/future split. Use these to calculate the expected position and compare with the actual position. This method is useful when the data are unstable. The Bonhuetter-Ferguson method assumes that the expected incremental losses are proportional to the ultimate for the accident year not to the emerged to date.

## Failure Mode And Effect Analysis: Ford Motor Co., Ford Motor Co)

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## Examples Of Critical Assumptions

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## Probabilistic Risk Assessment

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## Advantage Forecasting Models

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## Ethics: The Role Of Ethical Issues In Business

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## Fraud Triangle Case Summary

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## Advantages And Disadvantages Of Forecasting

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## Advantages And Disadvantages Of Fuzzy Theory

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### Fault Tree Analysis Methodology

2358 Words | 10 Pages### Bonhuetter Ferguson Case Study

1253 Words | 6 Pages### Failure Mode And Effect Analysis: Ford Motor Co., Ford Motor Co)

1250 Words | 5 Pages### Examples Of Critical Assumptions

894 Words | 4 Pages### Probabilistic Risk Assessment

702 Words | 3 Pages### Advantage Forecasting Models

2690 Words | 11 Pages### Ethics: The Role Of Ethical Issues In Business

958 Words | 4 Pages### Fraud Triangle Case Summary

1797 Words | 8 Pages### Advantages And Disadvantages Of Forecasting

961 Words | 4 Pages### Advantages And Disadvantages Of Fuzzy Theory

1021 Words | 5 Pages