• Title/Summary/Keyword: safety-critical system

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Implementation of Methodology & Tool for Communication Safety Guarantee in Railway System (철도시스템 통신 안전성 확보를 위한 방법 제시 및 도구 구현)

  • Jo, Hyun-Jeong;Hwang, Jong-Gyu;Kim, Yong-Kyu
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.59 no.1
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    • pp.10-17
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    • 2010
  • Safety-critical systems related to the railway communications are currently undergoing changes. Mechanical and electro-mechanical devices are being replaced by programmable electronics that are often controlled remotely via communication networks. Therefore designers and operators now not only have to contend with component failures and user errors, but also with the possibility that malicious entities are seeking to disrupt the services provided by theirs systems. Recognizing the safety-critical nature of the types of communications required in train control operations, the communications infrastructure will be required to meet a number of safety requirements such as system faults, user errors and the robustness in the presence of malicious attackers who are willing to take determined action to interfere in the correct operation of a system. In this paper, we proposed the safety strategies employed in the railway communications and a security mechanism for Korean railway communication system. Also, we presented the developed means for validation and determination of communication safety based on the proposed security mechanism in the railway system.

Design and Implementation of Safety-Critical Real-Time Operating System (Safety-Critical Real-Time Operating System의 설계 및 구현)

  • 윤기현;김용희;박희상;성영락;이철훈
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04a
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    • pp.226-228
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    • 2003
  • 실시간 운영체제(Real-Time Operating System)는 그 실행환경상 시스템이 예상치 못한 특정 이벤트가 발생하는 악 조건속에서도 태스크 수행의 데드라인을 초과하지 않도록 시간적인 측면의 determinism을 보장하는 안정된 스케줄링 기능을 갖춘 운영체제이다. 또한, 예상치 못한 fault 를 미연에 방지할 수 있는 장치를 가지고 있어야 한다. 본 논문에서는 예상치 못한 fault 를 미연에 방지하기 위하여 필요한 운영체제를 설계 및 구현하는데 그 목적이 있다.

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Experimental Study on Calculation of Critical Velocity in Accordance with Gradient of a Road Tunnel at Fire (도로터널 화재시 경사도에 따른 임계풍속산정에 관한 실험적 연구)

  • Kim, Jong-Yoon;Seo, Tae-Beom;Rie, Dong-Ho;Lim, Kyung-Bum;Yoo, Ji-Oh
    • Journal of the Korean Society of Safety
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    • v.21 no.5 s.77
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    • pp.1-5
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    • 2006
  • This study provides a basic data necessary to design a facility of smoke management after calculating the critical velocity of the gradient scale model tunnel and reviewing its adequacy to establish an optimum disaster prevention system for a road tunnel at fire. The experiment is carried out by using Froude scaling to a scale model which is about 1/29 as big as the real tunnel, and its critical velocity calculation is calculated to the 0-2% gradient of the tunnel. The result shows that the higher the gradient is, the stronger the critical velocity, but that it doesn't affect the critical velocity so much when the gradient is less 2%. In addition, this result is studied in comparison with the results done by other researchers to review the adequacy of the critical velocity.

The study on the applicability of Galileo system in railway application (철도응용분야에서의 갈릴레오 시스템의 적용방안 연구)

  • Shin, Kyung-Ho;Joung, Eui-Jin;Lee, Jun-Ho;Jeong, Rag-Gyo
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.947-952
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    • 2007
  • EU is in the process of developing a new european global navigation satellite system - Galileo project - which technologies and capitals from member states of EU are put into, after determining to set up a separate GPS against that of US late in the 1990s. Galileo system is commercial global navigation satellite system, which allows other else nations outside of EU to participate in system development and operation, different from GPS. Korea also decided to join in the project on February in 2005. Galileo system provide 5 Services - Open Service, Safety of Life, Commercial Service, Public Regulated Service, Search and Rescue Service, and especially it can be applicable to safety-critical areas, and is to provide its part of services certified. In this paper, we are to compare the services of Galileo system, and to present necessary factors to be considered, and the applicability to use the Galileo system in safety-critical application areas, such as train control system

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A Study on the Safety Requirements Establishment through System Safety Processes (시스템 안전성평가를 통한 효율적 요건 도출방안 연구)

  • Yoo, Seung-woo;Jung, Jinpyong;Yi, Baeck-Jun
    • Journal of Aerospace System Engineering
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    • v.7 no.2
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    • pp.29-34
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    • 2013
  • Safety requirements for aircraft and system functions include minimum performance constraints for both availability and integrity of the function. These safety requirements should be determined by conducting a safety assessment. The depths and contents of aircraft system safety assessment vary depending on factors such as the complexity of the system, how critical the system is to flight safety, what volume of experience is available on the type of system and the novelty and complexity of the technologies being used. Requirements that are defined to prevent failure conditions or to provide safety related functions should be uniquely identified and traceable through the levels of development. This will ensure visibility of the safety requirements at the software and electronic hardware design level. This paper has prepared to study on promoting the efficiency of establishing hierarchical safety requirements from aircraft level function to item level through system safety processes.

Safety Evaluation on Real Time Operating Systems for Safety-Critical Systems (안전필수(Safety-Critical) 시스템의 실시간 운영체제에 대한 안전성 평가)

  • Kang, Young-Doo;Chong, Kil-To
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.10
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    • pp.3885-3892
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    • 2010
  • Safety-Critical systems, such as Plant Protection Systems in nuclear power plant, plays a key role that the facilities can be operated without undue risk to the health and safety of public and environment, and those systems shall be designed, fabricated, installed, and tested to quality standards commensurate with the importance of the functions to be performed. Computer-based Instrumentation and Control Systems to perform the safety-critical function have Real Time Operating Systems to control and monitoring the sub-system and executing the application software. The safety-critical Real Time Operating Systems shall be designed, analyzed, tested and evaluated to have capability to maintain a high integrity and quality. However, local nuclear power plants have applied the real time operating systems on safety critical systems through Commercial Grade Item Dedication method, and this is the reason of lack of detailed methodology on assessing the safety of real time operating systems, expecially to the new developed one. This paper presents the methodology and experiences of safety evaluation on safety-critical Real Time Operating Systems based upon design requirements. This paper may useful to develop and evaluate the safety-critical Real Time Operating Systems in other industry to ensure the safety of public and environment.

An Empirical Study for Improving the Aptitude Management of the Railway's Safety-Critical Workers: Focusing on the Way of Stress Management (철도안전업무종사자의 적성관리 개선을 위한 실증 연구: 스트레스 요인의 관리방안을 중심으로)

  • Shin, Tack-Hyun
    • Journal of the Korean Society for Railway
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    • v.12 no.5
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    • pp.605-612
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    • 2009
  • The purpose of this article is to empirically suggest the necessity of reconsidering the new aptitude factors such as the ability to withstand work stress, to handle unusual events, and to work independently, in the respect that the environmental change in railway safety-critical worker's job should be flexibly reflected in the current aptitude management system. Besides, several ways of reducing the stress level for the railway safety-critical workers were suggested as well.

A Comparative Study of Formal Methods for Safety Critical Software in Nuclear Power Plant

  • Sedo Sohn;Seong, Poong-Hyun
    • Nuclear Engineering and Technology
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    • v.32 no.6
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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.

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Effects of Clinical Nurses Critical Reflection Competency, Professional Pride, and Person-Centered Care Practice on Patient Safety Management Activities (임상간호사의 비판적 성찰 역량, 전문직 자부심, 인간중심간호 수행이 환자안전간호활동에 미치는 영향)

  • Lee, Subin;Shin, Sujin
    • Journal of Korean Critical Care Nursing
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    • v.16 no.3
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    • pp.87-98
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    • 2023
  • Purpose : This descriptive survey investigated the effects of clinical nurses' critical reflection competency, professional pride, and person-centered care practices on patient safety management activities. Methods : The participants were 183 clinical nurses working at a tertiary hospital in South Korea. The questionnaires consisted of the Critical Reflection Competency Scale for Clinical Nurses Professional Pride the Person-Centered Nursing Assessment Tool and Patient Safety Management Activities. The collected data were analyzed using descriptive statistics, t-tests, ANOVA, Tukey's HSD, Pearson's correlation coefficient, and multiple regression using SPSS 29.0. Results : The mean score for patient safety management activities was 4.65±0.34 out of 5. There were significant differences in patient safety management activities according to age (F=3.90, p =.010), education level (t=-2.56, p =.013), total work experience (F=3.87, p =.010), and the number of healthcare accreditation system experiences (F=5.22, p =.006). Patient safety management activities were positively correlated with critical reflection competency (r=.337, p <.001), professional pride (r=.271, p <.001), and person-centered care practices (r=.399, p <.001). The results indicated that person-centered care practices affected patient safety management activities (𝛽=.358, p <.001) with the explanatory power of 22.5%. Conclusion : To improve clinical nurses' patient safety management activities, it is necessary to develop participatory educational programs that can integrate skills and attitudes based on conceptual knowledge of person-centered care. Intervention studies are needed to test the effect of person-centered care on patient safety when applied in clinical practice.

A Korean Food Safety Management System(FSMS) Based on the Premises of ISO 22000 (ISO 22000 국제규격 제정에 따른 한국형 식품안전경영시스템(FSMS) 구축모델과 적용방안)

  • Moon, Jae-Sung;Yoo, Wang-Jin;Lee, Cheol-Gyu
    • Journal of Korean Society for Quality Management
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    • v.33 no.3
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    • pp.41-46
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    • 2005
  • The production, processing, sale and service of food materials are not subject to attainment via a single country. In accordance with internationalization of the world, issues related to food safety have emerged as critical international concerns and they are closely associated with the health and interest of domestic consumers, producers, manufacturers, and distributors. As a third party certification standards, ISO 22000 is in progress International Organization for Standardization(ISO) and the Draft International Standard(DIS) has already been presented on December 2004. The purpose of this study is to analyze the international standards, guidelines and legislation in regard of Food Safety Management System(FSMS) including ISO 9001, Hazard Analysis Critical Control Point(HACCP) and Product Liability(PL) so as to present Korean-model Food Safety Management System requirements and system establishment model.