• 대한안전경영과학회지
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• 제13권4호
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• pp.9-16
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• 2011

Modern systems become more complex and the demand for systems safety goes up sharply. Thus, the proper handling of the safety requirements in the systems design is getting greatly increased attention these days. Hazard analysis has been one of the active areas of research in connection with systems safety. In this paper, we study a subject on how the hazard analysis results can be incorporated in the systems design. To this end we set up a goal on how to systematically generate safety requirements that should reflect hazard analysis results and be implemented in the systems design and development. To do so, we first review the process for systems design and suggest the associated Model. Then the process and results of hazard analysis are analyzed and Modeled particularly with emphasis on the safety data. The resulting data Model incorporating both the hazard analysis and system life cycle is used in the generation of safety requirements. Based on the developed data Model, the generation of the requirements, the construction of requirements DB, and the change management later on is demonstrated through the use of a computer-aided software tool.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권1호
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• pp.81-91
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• 2014

The IEC 61508 standard was established to specify the functional safety of E/E/PE safety-related systems. Safety life cycle to provide the framework and direction for the application of IEC 61508 is included in this standard. In this paper, we describe overviews, objects, scopes, requirements and activities of each phase in safety life cycle. In addition, we introduce safety integrity level(SIL) which is used for verifying the safety integrity requirements of E/E/PE system and perform a case study to estimate hardware SIL by FMEDA. The SIL is evaluated by two criteria. One of them is the architectural constraints which restrict the maximum SIL by combination of SFF and HFT. The other is the probability of failure which is classified into PFD and PFH based on frequency of demand and calculated by safe or dangerous failure rates.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2004년도 추계학술대회
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• pp.277-287
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• 2004

This study presents a method of quality category classification by safety, maturity, complexity, and what types and extent of controls and verifications are applied to specific products and services during the various stages of a nuclear facility life cycle. All products, services and processes have various controls and verifications built in to ensure they perform their functions satisfactorily. The highest grade should require the most stringent application of the quality assurance requirements ; while, the lowest grade should require the least stringent. When products or services are modified, the assigned grade of quality assurance requirements could become more stringent or less stringent depending on the significance in nuclear safety. Applying QA program always costs money, and they should be applied and focused to the extent where necessary and not applied or applied to a lesser degree for less important activities. An efficient QA program should be developed to satisfy the necessary requirements and to ensure the required confidence in quality, but without unnecessary stipulations. Not all the requirements of QA standard must be applied identically to all products and services which are to be provided.

• 대한안전경영과학회지
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• 제11권3호
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• pp.19-26
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• 2009

It is becoming more and more important to develop safety-critical systems with special attention. Examples of the safety-critical systems include the mass transportation systems such as high speed trains, airplanes, ships and so forth. Safety critical issues can also exist in the development of atomic power plants that are attracting a great deal of attention recently as oil prices are sky-rocketing. Note that the safety-critical systems are in general large-scale and very complex for which case the effects of adopting the systems engineering (SE) approach has been quite phenomenal. Furthermore, safety-critical requirements should necessarily be realized in the design phase and be effectively maintained thereafter. In light of these comments, we have considered our approach to developing safety-critical systems to be based on the method combining the systems engineering and safety management processes. To do so, we have developed a design environment by constructing a whole life cycle model in two steps. In the first step, the integrated process model was developed by integrating the SE (ISO/IEC 15283) and systems safety (e.g., hazard analysis) activities and implemented in a computer-aided SE tool environment. The model was represented by three hierarchical levels: the life-cycle level, the process level, and the activity level. As a result, one can see from the model when and how the required SE and safety processes have to be carried out concurrently and iterately. Finally, the design environment was verified by the computer simulation.

• 대한안전경영과학회지
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• 제15권1호
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• pp.11-19
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• 2013

In modern systems design and development, one of the key issues is considered to be related with how to reflect faithfully the stakeholder requirements including customer requirements therein, thereby successfully implementing the system functions derived from the requirements. On the other hand, the issue of safety management is also becoming greatly important these days, particularly in the operational phase of the systems under development. An approach to safety management can be based on the use of the failure mode effect and analysis (FMEA), which has been a core method adopted in automotive industry to reduce the potential failure. The fact that a successful development of cars needs to consider both the complexity and failure throughout the whole life cycle calls for the necessity of applying the systems engineering (SE) process. To meet such a need, in this paper a method of FMEA is developed based on the SE concept. To do so, a process model is derived first in order to identify the required activities that must be satisfied in automotive design while reducing the possibility of failure. Specifically, the stakeholder requirements were analyzed first to derive a set of functions, which subsequentially leads to the task of identifying necessary HW/SW components. Then the derived functions were allocated to appropriate HW/SW components. During this design process, the traceability between the functions and HW/SW components were generated. The traceability can play a key role when FMEA is performed to predict the potential failure that can be described with the routes from the components through the linked functions. As a case study, the developed process model has been applied in a project carried out in practice. The results turned out to demonstrate the usefulness of the approach.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.683-688
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• 2007

The importance of reliability and safety, recently, shows a tendency to increases in railway system constructions and projects. At the point of view of safety, especially, the railway authority proposes an establishment of the safety case that is the documented demonstration that products comply with the specific safety requirements in railway industry. In case of reliability activities, there is no systematic documented demonstration in the railway industry. At this circumstance, this study presents the establishment of Reliability, Availability and Maintainability Case for railway system based on the MoD(Ministry of Defence) 00-42. This RAM Case will support that systems and products produced from suppliers or manufacturers meet the specific RAM requirements during the system life cycle(i.e, from design to operation & maintenance) through systematic process and evidences. Also, it is expected that railway system operations will be managed and supported from reliability activities in accordance with RAM Case.

• 한국재난정보학회 논문집
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• 제5권2호
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• pp.10-21
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• 2009

This study contains the fire protection safety of the public-utilization shops. The toll of fires in the public-utilization shops is so heavy in spite the less occurency. The shops are mostly compartmented into small rooms by partition wall which hinders the evacuation of the people on fire. This study provides additional requirements on the fire safety of the public-utilization shops needed for human life and property.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제6권12호
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• pp.543-548
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• 2017

최근에는 의료기기의 구성 요소 중 소프트웨어의 기능과 역할이 커지고, 의료기기 소프트웨어의 작동이 사용자의 생명과 안전에 직결되는 특성으로 인해 의료기기 소프트웨어의 안전성 보장에 대한 중요함은 더욱 강조되고 있다. 이를 위해 의료기기의 안전성을 효과적으로 보장할 수 있는 활동과 각각의 요구사항들을 제시하고 있는 여러 표준이 제정되었다. 표준들이 의료기기 소프트웨어의 안전성을 보장하기 위해 제시하는 활동으로는 크게 의료기기 소프트웨어의 개발생명주기와 위험관리 프로세스로 나뉜다. 이 두 활동은 개발 과정 중 동시에 진행되어야 하지만, 의료기기 소프트웨어 개발생명주기의 각 단계에서 수행되어야하는 위험관리 요구사항들은 분류되어있지 않다는 한계점이 있다. 이로 인해 개발자들은 의료기기 개발 중에 직접 표준들의 연관성을 분석하여 위험관리 활동을 수행해야한다. 따라서 본 논문에서는 의료기기 소프트웨어 개발생명주기와 위험관리 프로세스의 연관성을 분석하고, 위험관리 요구사항 항목들을 추출한다. 그리고 분석한 연관성을 토대로 추출된 위험관리 요구사항 항목을 개발생명주기에 대응시킴으로서, 의료기기 소프트웨어의 개발 중 효과적이고 체계적인 위험관리를 가능하게 한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1118-1125
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• 2010

This paper presents the methods to acquire the Safety Certificate from Independent Safety Assessment based on the IEC standard62279 which is commonly applied to railway system for Automatic Train Control(ATC) system in accordance with Urban Maglev project. This also shows approach methods and relative activities for project life-cycle to accomplish and ensure the system requirements of ATC system, RAMS and S/W quality activities. Furthermore, the key tasks conducted with ISA are noted in detail. These kind of activities for software quality of ATC system to obtain Safety Certificate could be a CASE model to improve the quality of domestic railway system and products, and also contribute to the growth of railway business and toward the achievement of overseas' railway signaling markets.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2004년도 품질경영모델을 통한 가치 창출
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• pp.114-119
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• 2004

Software verification and validation(V&V) is a means to develop high-quality software and assure safety and reliability for software. Also, we can achieve the desired software quality through systematic V&V activities. The software to be applied safety critical system like nuclear power plants is required to setup the V&V methodology that comply with licensing requirements for nuclear power plants and should be performed V&V activities according to it. In this paper, we classified safety-critical, safety-related and non-safety for software according to safety function to be peformed and define V&V activities to be applied software grade. Also, we defined V&V activities, procedures and documentation for each phase of software development life cycle and showed techniques and management to perform V&V. Finally, we propose the V&V framework to be applied software development of SMART(System-integrated Modular Advanced ReacTor) MMIS (Man-Machine Interface System) and to comply with domestic licensing requirements.