• Nuclear Engineering and Technology
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• 제52권7호
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• pp.1462-1470
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• 2020

Reliability in safety-critical systems and equipment is of vital importance, so the probabilistic safety assessment (PSA) has been widely used for many years in the nuclear industry to address reliability in a quantitative manner. As many nuclear power plants (NPPs) become digitalized, evaluating the reliability of safety-critical software has become an emerging issue. Due to a lack of available methods, in many conventional PSA models only hardware reliability is addressed with the assumption that software reliability is perfect or very high compared to hardware reliability. This study focused on developing a new method of safety-critical software reliability quantification, derived from hardware-software integrated environment testing. Since the complexity of hardware and software interaction makes the possible number of test cases for exhaustive testing well beyond a practically achievable range, an importance-oriented testing method that assures the most efficient test coverage was developed. Application to the test of an actual NPP reactor protection system demonstrated the applicability of the developed method and provided insight into complex software-based system reliability.

• 전기학회논문지P
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• 제58권2호
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• pp.95-100
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• 2009

Recent advances in computer technology have brought more dependence on software to railway systems. Hence, the safety assurance of the vital software running on the railway system is very critical task and yet, not many works have been done. While much efforts have been reported to improve electronic hardware's safety, not so much systematic approaches to evaluate software's safety. In this paper, we suggested an automated analysis tool for S/W change impact in railway system, and presented its result of implementation. The analysis items in the implemented tool had referred to the international standards in relation to the software for railway system, such as IEC 61508 and IEC 62279. In these international standards, 'change impact analysis' for railway system S/W has to be required mandatorily. The proposed tool can be utilized at the assessment stage and also the software development stage.

• Nuclear Engineering and Technology
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• 제32권6호
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• pp.537-548
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• 2000

The requirement of ultra high reliability of the safety critical software can not be demonstrated by testing alone. The specification based on formal method is recommended for safety system software. But there exist various kinds of formal methods, and this variety of formal method is recognized as an obstacle to the wide use of formal method. In this paper six different formal method have been applied to the same part of the functional requirements that is calculation algorithm intensive. The specification results were compared against the criteria that is derived from the characteristics that good software requirements specifications should have and regulatory body recommends to have. The application experience shows that the critical characteristics should be defined first, then appropriate method has to be selected. In our case, the Software Cost Reduction method was recommended for internal condition or calculation algorithm checking, and statechart method is recommended for the external behavioral description.

• International Journal of Internet, Broadcasting and Communication
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• 제16권1호
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• pp.140-147
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• 2024

In Current artificial structures, we must periodically make their safety inspections. In this process, we should consider the safety of workers and the accuracy of safety checks and also consider time and cost savings for safety inspections. Additionally, in the fields of architecture and civil engineering, we are unavoidable the use of foreign commercialized BIM model tools. To address these challenges, we propose mapping crack areas and BIM 3D design drawings based on augmented reality (AR) for the safety inspection of Huge Bridges. For this purpose, we define indexing of 2D/3D drawing models, create the tabulation of all 2D/3D drawings into a database, analyze QR codes, and finally integrate with augmented reality devices. we may expect our method to improve the efficiency of safety inspections on bridge sites. Moreover, we will enable the domestics of our pure technology.

• 한국항공우주학회지
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• 제46권1호
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• pp.86-94
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• 2018

항공기 시스템에서 소프트웨어의 사용이 증가 추세에 있어 안전 및 보안 위협에 대한 노출이 점차 증대되고 있다. 소프트웨어 안전에 관한 인증기준은 DO-178C가 발표되었으나, 소프트웨어 보안을 위한 인증기준은 포함되어 있지 않다. 한편 최근 항공기 및 시스템 감항 보안 인증기준으로 DO-326A, DO-356 및 DO-355가 별도로 발표되었다. 그러나 안전과 보안의 인증을 위해 각각의 기준과 절차를 준수함으로써 별도의 비용과 노력이 요구되는 실정이다. 따라서 본 논문에서는 안전과 보안을 위한 각각의 인증기준을 하나로 통합하여 비용, 노력 및 시간 등을 감소시킬 수 있는 효율적인 통합인증 방안을 제시하고자 한다.

• 품질경영학회지
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• 제46권4호
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• pp.1001-1014
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• 2018

Purpose: Autonomous driving cars, which are often represent the new convergence product, have been researched since the early years of 1900 but their safety assurance policies are yet to be implemented for real world practices. The primary purpose of this paper is to propose a modular concept based on which a safety assurance system can be designed and implemented for operating autonomous driving cars. Methods: We combine a set of key attributes of CE mark (European Assurance standard), E-Mark (Automobile safety assurance system), and A-SPICE (Automobile software assurance standard) into a modular approach. Results: Autonomous vehicles are emphasizing software safety, but there is no integrated safety certification standard for products and software. As such, there is complexity in the product and software safety certification process during the development phase. Using the concept of module, we were able to come up with an integrated safety certification system of product and software for practical uses in the future. Conclusion: Through the modular concept, both international and domestic standards policy stakeholders are expected to consider a new structure that can help the autonomous driving industries expedite their commercialization for the technology advanced market in the era of Industry 4.0.

• 전기학회논문지P
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• 제58권2호
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• pp.108-115
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• 2009

Recent advances in computer technology have brought more dependence on software to train control systems. Hence, the safety assurance of the vital software running on the railway system is very critical task and yet, not many works have been done. While much efforts have been reported to improve electronic hardware's safety, not so much systematic approaches to evaluate software's safety, especially for the vital software running on board train controllers. In this paper, we have developed the static software testing tool for railway signaling, especially Fagan Inspection module and checklists supporting module. This static testing tool for railway signaling can be utilized at the assessment phase, and also usefully at the software development stage also. It is anticipated that it will be greatly helpful for the evaluation on the software for railway signalling system.

• 품질경영학회지
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• 제41권3호
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• pp.433-441
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• 2013

Purpose: This study investigates software qualification procedures based on the FA-50 flight control software to satisfy high reliability and flight safety. Methods: We studied software qualification categories, standard/specification and developed country case. We proposed procedure to satisfy not only flight safety but also international standard. Results: The proposed software qualification procedure satisfied flight safety and airworthiness based on the testing result of the FA-50 flight control software. Conclusion: This paper showed an appropriate qualification procedures of the flight control software in domestic circumstance through the FA-50 flight control software qualification.

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.404-418
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• 2016

This paper presents a documentation and development method to facilitate the certification of scientific computing software used in the safety analysis of nuclear facilities. To study the problems faced during quality assurance and certification activities, a case study was performed on legacy software used for thermal analysis of a fuelpin in a nuclear reactor. Although no errors were uncovered in the code, 27 issues of incompleteness and inconsistency were found with the documentation. This work proposes that software documentation follow a rational process, which includes a software requirements specification following a template that is reusable, maintainable, and understandable. To develop the design and implementation, this paper suggests literate programming as an alternative to traditional structured programming. Literate programming allows for documenting of numerical algorithms and code together in what is termed the literate programmer's manual. This manual is developed with explicit traceability to the software requirements specification. The traceability between the theory, numerical algorithms, and implementation facilitates achieving completeness and consistency, as well as simplifies the process of verification and the associated certification.

• 한국의료질향상학회지
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• 제24권1호
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• pp.9-22
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• 2018

Purpose: The purpose of this study is to develop the Korean root cause analysis (RCA) software that can be used to systematically investigate underlying causes for preventing or reducing recurrence of patient safety incidents. Methods: We reviewed the existing guidelines and literatures on the RCA in order to figure out the RCA process. Also we examined the existing RCA softwares for investigating patient safety incidents to design the contents and interface of the RCA software. Based on the results of reviewing literatures and softwares, we developed a draft version of the Korean RCA software that can be easily used in Korean hospital settings by RCA teams. Results: The Korean RCA software consisted of several modules, which are modules for identifying patient safety incidents, organizing RCA team, collecting and analysing data, determining contributory factors and root causes, developing the action plans, and guiding evaluation. Conclusion: The Korean RCA software included optimized RCA process and structured logic for cause analysis. Thus even beginners in RCA are expected to easily use this software for investigating patient safety incidents. As software has been developed with the public financial support, it will be distributed free of charge. We hope that it will contribute to facilitating patient safety improvement activities in Korea.