• Title/Summary/Keyword: reliability and safety

Search Result 3,067, Processing Time 0.041 seconds

Verification and Validation to develop Safety-critical Software (안전에 중요한 소프트웨어 개발을 위한 확인 및 검증)

  • Lee Jong-Bok;Suh Sang-Moon;Keum Jong-Yong
    • Proceedings of the Korean Society for Quality Management Conference
    • /
    • 2004.04a
    • /
    • pp.114-119
    • /
    • 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.

  • PDF

On the Ensuring Safety and Reliability through the Application of ISO/PAS 21448 Analysis and STPA Methodology to Autonomous Vehicle

  • Kim, Min Joong;Choi, Kyoung Lak;Kim, Joo Uk;Kim, Tong Hyun;Kim, Young Min
    • International Journal of Internet, Broadcasting and Communication
    • /
    • v.13 no.3
    • /
    • pp.169-177
    • /
    • 2021
  • Recently, the use of electric and electronic control systems is increasing in the automobile industry. This increase in the electric and electronic control system greatly increases the complexity of designing a vehicle, which leads to an increase in the malfunction of the system, and a safety problem due to the malfunction is becoming an issue. Based on IEC 61508 relating to the functional safety of electrical/electronic/programmable electronics, the ISO 26262 standard specific to the automotive sector was first established in 2011, and a revision was published in 2018. Malfunctions due to system failure are covered by ISO 26262, but ISO/PAS 21448 is proposed to deal with unintended malfunctions caused by changes in the surrounding environment. ISO 26262 sets out safety-related requirements for the entire life cycle. Functional safety analysis includes FTA (Fault Tree Analysis), FMEA (Failure Mode and Effect Analysis), and HAZOP (Hazard and Operability). These analysis have limitations in dealing with failures or errors caused by complex interrelationships because it is assumed that a failure or error affecting the risk occurs by a specific component. In order to overcome this limitation, it is necessary to apply the STPA (System Theoretic Process Analysis) technique.

The Comparative Study on Safety Factors at Elevator Management System Operation (승강기 관리시스템 운영 시 안전요소에 관한 비교연구)

  • Park, Joo-Bong;Shin, Seung-Jung
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.14 no.6
    • /
    • pp.159-162
    • /
    • 2014
  • Recently, from 2008 to 2012, there are many of elevator safety patents from patent office survey. In this paper, we analyzed the elevator safety patent from 2009 to 2013, found out safety factor is safety control, emergency stop equipment and door opening equipment. Through reliability statistics, we defined the most important things for safety elevator factor is this three things, studied the reason about many patents. Finally, we propose the Kinect Scada elevator system for prevention safety accident.

Risk Analysis of Off-site Risk Assessment using Vulnerability by Environmental Medium (환경매체별 취약성을 반영한 장외영향평가 위험도 분석)

  • Choi, Woo Soo;Back, Jong Bae
    • Journal of the Korean Society of Safety
    • /
    • v.33 no.5
    • /
    • pp.150-156
    • /
    • 2018
  • As the types and usage of chemical increase, modern countries should protect their health and environment from the risk of hazardous chemical. Chemical accidents not only affect humans but also cause huge losses to the environment. Moreover, since its effects do not end in a short period of time, it is necessary to identify the extent of the damage and establish a prevention and response system in advance. In 2015, the Chemical Substances Management Act provided a system for assessing the impact on the people and the environment around the workplace. However, it is difficult to quantitatively evaluate the impact on environmental factors such as vegetation and aquatic, with the current hazard assessment methods. The purpose of this study is to analyze the quantitative risk of environmental receptors. This study improved the existing risk assessment formula by using the environmental vulnerability index and established the end point concentration criterion which can estimate the damage range to environmental media. To verify the results of the study, a virtual accident scenario was selected and a case study was conducted. As a result, the extent of impact on the environmental medium can be calculated, and the degree of environmental risk of the zone can be quantified through the risk analysis considering the environmental vulnerability. This study is expected to increase the reliability of the reliability of the existing risk anaylsis method beacause it is a risk analysis method that can be applied when the environmental factors are absolutely necessary and when the residents and environment are complex.

On derivation the System Analysis and Evaluation Indicators of Blockchain-based Smart Electronic Transport Waybill Platform for Improvement of Logistics Service Operation Efficiency and Personal Information Security (물류 서비스 운영 효율과 개인정보 보안 향상을 위한 블록체인 기반 스마트 전자 운송장 플랫폼 시스템 분석 및 평가지표 도출에 관한 연구)

  • Park, Jae-Min;Won, JoNg-Woon;Seong, Ki-Deok;Kim, Young-Min
    • Journal of the Korea Safety Management & Science
    • /
    • v.22 no.4
    • /
    • pp.75-86
    • /
    • 2020
  • With the advent of the 4.0 era of logistics due to the Fourth Industrial Revolution, infrastructures have been built to receive the same services online and offline. Logistics services affected by logistics 4.0 and IT technology are rapidly changing. Logistics services are developing using technologies such as big data, artificial intelligence, blockchain, Internet of things, and augmented reality. The convergence of logistics services and various IT new technologies is accelerating, and the development of data management solution technology has led to the emergence of electronic cargo waybill to replace paper cargo waybill. The electronic waybill was developed to supplement paper waybill that lack economical and safety. However, the electronic waybill that appeared to complement the paper waybill are also in need of complementation in terms of efficiency and reliability. New research is needed to ensure that electronic cargo waybill gain the trust of users and are actively utilized. To solve this problem, electronic cargo waybill that combine blockchain technology are being developed. This study aims to improve the reliability, operational efficiency and safety of blockchain electronic cargo waybill. The purpose of this study is to analyze the blockchain-based electronic cargo waybill system and to derive evaluation indicators for system supplementation.

Safety-Related Equipment Classification for Maintenance Purposes with Risk Measures

  • Park, Byoung-Chul;Kwon, Jong-Jooh;Cho, Sung-Hwan
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 1998.05a
    • /
    • pp.838-843
    • /
    • 1998
  • Risk importance measures are widely wed to rank risk contributors in risk-based applications. Typically, Fussell-Vesely (F-V) importance and risk achievement worth (RAW) are used in the component importance raking for the reliability centered maintenance (RCM) analysis of safety system in nuclear power plants (NPPs). This study was performed as part of feasibility study on RCM for domestic NPPs, which is focused on the component importance ranking approach the maintenance recommendation. The approach of modulizing faulting tree basic events was applied in the simplification process of the PSA model and the validity of the approach was evaluated As a result of the case study, this paper included the importance and the maintenance recommendations for the safety-related equipments associated with safety injection and containment spray in large loss of coolant accident sequences.

  • PDF

Parameter Estimation and Reliability Analysis Using Bayesian Approach for Bolted Joint and O-ring Seal of Solid Rocket Motor (고체 로켓 모터의 체결 볼트와 오링에 대한 베이지안 접근법 기반 모수 추정과 신뢰성 해석)

  • Gang, Jin Hyuk;Choi, Joo Ho
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.41 no.11
    • /
    • pp.1055-1064
    • /
    • 2017
  • Since a device such as a rocket motor requires very high reliability, a reasonable reliability design process is essential. However, Korea has implemented a design method for applying a safety factor to each component. In classic reliability analysis, input variables such as mean and standard deviation, used in the limit state function, are treated as deterministic values. Because the mean and standard deviation are determined by a small amount of data, this approach could lead to inaccurate results. In this study, reliability analysis is performed for bolted joints and o-ring seals, and the Bayesian approach is used to statistically estimate the input variables. The estimated variables and failure probability, calculated by the reliability analysis, are derived in the form of probability distributions.

Evaluation of Performance and Reliability of a White Organic Light-Emitting Diode(WOLED) Using an Accelerated Life Test(ALT) (가속수명시험(ALT)을 이용한 WOLED의 성능 및 신뢰성 평가)

  • Moon, Jin-Chel;Park, Hyung-Ki;Choi, Chung-Seog
    • Journal of the Korean Society of Safety
    • /
    • v.27 no.4
    • /
    • pp.13-19
    • /
    • 2012
  • The purpose of this study is to extract the major factors related to the deterioration mechanism of white organic light-emitting diodes(WOLED) by performing accelerated testing of temperature, voltage, time, etc., and to develop an accelerated life test(ALT) model. The measurement results of the brightness of the WOLED exhibited that their average brightness tended to increase as the operating voltage increased and that the half-life period of the brightness appeared after approximately 400 hours when the operating voltage was 20V and the ambient temperature was $85^{\circ}C$. It could be seen that although the WOLED showed comparatively the same brightness when the initial acceleration began after the operating voltage was applied to it, its brightness changed excessively after the WOLED's thermal storage had been made. In addition, it was observed that the half-life period was reduced as the ambient temperature and applied voltage increased. The strength of the WOLED which had been maintained in the range of visible light at the maximum load was reduced by the deterioration of the organic light emitting material due to the influence of the operating voltage and temperature, and the reduction of emitted light was small at low voltage and temperature. It could be seen that the failure of the WOLED during the ALT was caused by wear due to load accumulation over time, and that Weibull distribution was appropriate for the life distribution and acceleration was established between test conditions. From the WOLED analysis, it is thought that factors influencing the brightness deterioration are voltage, temperature, etc., and that comprehensive analysis considering discharge control, dielectric tangent margin, etc., would further increase the reliability.

The Functional Safety Assessment of WIG Craft in Design Stage (위그선 설계단계에서의 안전성 평가)

  • Lee, Soon-Sup;Park, Beom-Jin;Lee, Jong-Kap
    • Journal of Ocean Engineering and Technology
    • /
    • v.24 no.6
    • /
    • pp.103-108
    • /
    • 2010
  • WIG crafts are high speed vessels with the features of a dynamic supported craft. These crafts, which are predominantly lightweight and operate at substantially greater speeds than conventional craft, could not be accommodated under traditional maritime safety instruments. WIG crafts inherently possess more hazard factors than conventional ships because of their relatively high speed, lightweight, and navigational characteristics, and an accident is likely to cause damage to the ship and a high loss of life. Because WIG crafts are composed of many systems and subsystems, the safety assessment of a WIG must use a commercial software system in the design stage. This paper reviews a safety assessment process and methodology proposed by the IMO interim guideline, which were developed in view of the configuration of WIG crafts. This safety assessment system was developed to fit the WIG's safety assessment process using a reliability analysis system widely used in commercial systems. The FHA was performed on the functional hazards of systems in the conceptual design stage.

A Study on Explosion Risk Management for Hot Oil Heater (열매체 가열기 설비에서의 폭발위험관리에 관한 연구)

  • Jang, Chul;Kwon, Jin-Wook;Hwang, Myoung-Hwan
    • Journal of the Korea Safety Management & Science
    • /
    • v.19 no.3
    • /
    • pp.1-9
    • /
    • 2017
  • In the industrial field, various type of fuel have been used for product processing facilities. Recent for 10 years, the usage of natural gas (NG) was gradually increased. Because it has many merits; clean fuel, no transportation, storage facility and so on. There are common safety concept that strict explosion protection approaches are needed for facilities where explosive materials such as flammable liquid, vapor and gases exist. But some has an optimistic point of view that the lighter than air gases such as NG disperse rapidly, hence do not form explosion environment upon release into the atmosphere, many parts has a conventional safety point of view that those gases are also inflammable gases, hence can form explosion environment although the extent is limited and present. In this paper, the heating equipments (Hot Oil Heater) was reviewed and some risk management measures were proposed. These measures include hazardous area classification and explosion-proof provisions of electric apparatus, an early gas leak detection and isolation, ventilation system reliability, emergency response plan and training and so on. This study calculates Hazardous Area Classification using the hypothetical volume in the KS C IEC code.