A Study on SIL Allocation for Signaling Function with Fuzzy Risk Graph

퍼지 리스크 그래프를 적용한 신호 기능 SIL 할당에 관한 연구

Yang, Heekap;Lee, Jongwoo

  • Received : 2016.01.29
  • Accepted : 2016.03.08
  • Published : 2016.04.30


This paper introduces a risk graph which is one method for determining the SIL as a measure of the effectiveness of signaling system. The purpose of this research is to make up for the weakness of the qualitative determination, which has input value ambiguity and a boundary problem in the SIL range. The fuzzy input valuable consists of consequence, exposure, avoidance and demand rate. The fuzzy inference produces forty eight fuzzy rule by adapting the calibrated risk graph in the IEC 61511. The Max-min composition is utilized for the fuzzy inference. The result of the fuzzy inference is the fuzzy value. Therefore, using the de-fuzzification method, the result should be converted to a crisp value that can be utilized for real projects. Ultimately, the safety requirement for hazard is identified by proposing a SIL result with a tolerable hazard rate. For the validation the results of the proposed method, the fuzzy risk graph model is compared with the safety analysis of the signaling system in CENELEC SC 9XA WG A10 report.


Risk graph;SIL(Safety Integrity Level);Fuzzification;Fuzzy inference;Defuzzification


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Grant : 퍼지 리스크 그래프를 적용한 신호 기능 SIL 할당에 관한 연구

Supported by : 서울과학기술대학교