Modern systems can be characterized by ever-increasing complexity of both the functionality and system scale. Thus, due to the complexity the chances of accidents resulting from systems failure can then be growing. Even worse is that those accidents could result in disastrous damage to the human being and properties as well. Therefore, the need for the developed systems to be assured with systems safety is apparent in a variety of industries such as rail, automobiles, airplanes, ships, oil refinery, chemical production plants, and so on. To this end, in the industry an appropriate safety standard has been published for its own safety-assured products. One of the core activities included in the most safety standards is hazard analysis. A conventional approach to hazard analysis seems to depend upon the scenarios derived from the ones used previously in similar systems or based on former experience. The objective of this paper is to study an improved process for scenario-based hazard analysis. To achieve the goal, the top-level safety requirements have first been reflected in the scenarios. By analyzing and using them, the result has then lead to the development of safety-assured systems. The method of modeling and simulation has been adopted in the generation and verification of scenarios to check whether the safety requirements are reflected properly in the scenarios. Application of the study result in the case of rail safety assurance has also been discussed.

Abstract
 1. 서론
 2. 문제 정의
  2.1 안정보장을 위한 위험원 분석의 중요성
  2.2 안전요건이 반영된 시나리오 생성의 필요성
  2.3. 연구 목표 및 범위
 3. 안전요건이 반영된 시나리오기반의위험원 분석 방법
  3.1. 안전요건이 반영된 시나리오의 생성 방안
  3.2. 모델링과 시뮬레이션을 활용한 시나리오의 생성 및 검증 방법
  3.3. 안전요건이 반영된 시나리오 기반의 위험원 분석방안
 4. 안전요건이 반영된 시나리오 기반의철도 시스템 위험원 분석
  4.1. 안전요건이 반영된 철도시스템 출발 시나리오의 생성 및 검증
  4.2. 안전요건이 반영된 시나리오 기반의위험원 식별
 5. 결론
 6. References
 저 자 소 개

• 정호전(아주대학교 시스템공학과) | Ho Jeon Jung
• 이재천(아주대학교 시스템공학과) | Jae-Chon Lee Corresponding author