Binary decision diagram quantitative analysis method based on fuzzy set theory

The purpose of this study is to develop a model to investigate the tourists’ preference. Ten attributes of tourist destinations were used in this study. Fuzzy set theory was adopted as the main analysis method to find the tourists’ preference. In this study, 248 pieces of data were used. Besides the evaluations for the factors, the overall evaluations (namely, satisfied, neutral, and dissatisfied) for every tourism destination were also inquired. After screening, 201 pieces of these data could be used. In these 201 pieces of data, 141 were classified into “satisfied” with the tourism destination, accounting for 70.15%, and 49 were “neutral,” accounting for 24.38%, while 11 were “dissatisfied,” accounting for 5.47%. Eight rules were obtained with the method of fuzzy preprocess. Regarding the condition attributes, three of the original ten attributes were found influential, namely, level of prices, living costs, information and tourist services, and tourist safety of the tourism destinations. From the results of this study, it is shown that top management of tourism destinations should put resources in these fields first, in order to allow limited resources to perform to maximum effectiveness.

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Quantitative HAZOP Risk Analysis for Oil Tanks Using the Fuzzy Set Theory

Volume 1: Upstream Pipelines; Project Management; Design and Construction; Environment; Facilities Integrity Management; Operations and Maintenance; Pipeline Automation and Measurement ◽

10.1115/ipc2012-90206 ◽

2012 ◽

Author(s):

Tao Cao ◽

Huabing Zhang ◽

Honglong Zheng ◽

Yufeng Yang ◽

Xin Wang

Keyword(s):

Quantitative Analysis ◽

Risk Analysis ◽

Set Theory ◽

Fuzzy Set ◽

Fuzzy Set Theory ◽

Fuzzy Numbers ◽

Storage Tanks ◽

Worst Case ◽

Quantitative Calculation ◽

Oil Storage

Oil storage tanks are identified as the major hazard installations because of the hazard of huge fire & explosion. Evaluating the risk and controlling the danger is the advancement of accident prevention and the compulsory requirement of laws. HAZOP (Hazard and Operability Analysis), is a simple but intensive, systematic, qualitative risk analytical method, is an important technique for the identification of hidden hazards in operation of tank facility. It can only qualitatively account for potential risks, but cannot quantify their possibility and severity. Thus, research involving HAZOP quantitative analysis has become an area of focus. Due to uncertainty of deviation probability in the traditional HAZOP analysis, this paper discusses a new approach of HAZOP quantitative analysis, combining HAZOP with fuzzy set theory to calculate the possibilities of deviation and consequence quantitatively. The evaluation process and technique route of risk analysis is also brought forward in this paper. Based on the traditional HAZOP analysis, the typical outputs of a HAZOP analysis can be achieved, including identification of possible deviation states, identification of the possible causes for deviations and probable worst case consequence. Next, according to fuzzy evaluation of some HAZOP experts on deviation by means of their knowledge, the triangular fuzzy-number is introduced in this paper to conduct quantitative calculation. Based on the fuzzy set theory, combining Delphi method and judging matrix method, the linguistic values are transformed into triangular fuzzy numbers. The probability of deviation is evaluated by fuzzy cut and raking method of fuzzy numbers. Finally, the probability of consequence caused by deviation is evaluated. A complete quantitative risk analysis example for oil tank is conducted, the probabilities of deviations and incident consequence are computed, the quantitative risk is determined and reasonable mitigations of the storage tanks are given. It is shown that the proposed approach is advanced and practicable to make a quantitative assessment on the risk of existing deviation, which is helpful for risk managers to bring forward the suggested measure and regulate the hidden hazards.

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Application of fuzzy set theory to structural reliability analysis. Method for combining a number of subjective evaluations.

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.39.14 ◽

1990 ◽

Vol 39 (436) ◽

pp. 14-18

Author(s):

Masahiro ICHIKAWA ◽

Takeo SUGIYAMA ◽

Kazuhiko KAKINUMA

Keyword(s):

Reliability Analysis ◽

Set Theory ◽

Fuzzy Set ◽

Fuzzy Set Theory ◽

Structural Reliability ◽

Analysis Method ◽

Structural Reliability Analysis ◽

Subjective Evaluations

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Importance Analysis Method of Fuzzy Fault Tree Based on T-S Modle and Application in Hydraulic System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.470.707 ◽

2013 ◽

Vol 470 ◽

pp. 707-711 ◽

Cited By ~ 1

Author(s):

Lu Lu Zhang ◽

Rui Jun Zhang ◽

Xin Xin Si

Keyword(s):

Set Theory ◽

Fuzzy Set ◽

Fuzzy Set Theory ◽

Hydraulic System ◽

Fault Tree ◽

Analysis Method ◽

Fuzzy Information ◽

Logical Relationship ◽

Importance Analysis ◽

Fuzzy Subsets

In order to overcome the shortage of dealing with fuzzy information and uncertainty of fault logical relationship in traditional importance measures, the fuzzy set theory is presented to fault tree, using fuzzy number to describe the fault states of system and components, and using fuzzy subsets to denote the fault rates, a fuzzy fault tree of T-S modle was established. And a model of fuzzy fault tree was established and a T-S fuzzy importance analysis method was presented on the basis of T-S analysis method. The method is applied in the importance analysis of hydraulic system, and proving that the algorithms are feasible.

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