• 제목/요약/키워드: Systematic Failure

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기능안전의 구현을 통한 Systematic Failure의 감축에 관한 연구 (On the Reduction of Systematic Failure by Realizing a Method for Functional Safety)

  • 정호전;박찬우;이재천
    • 대한안전경영과학회지
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    • 제15권4호
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    • pp.161-169
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    • 2013
  • Due to the recent advances in technology, the systems are becoming more demanding in terms of functionality and implementation complexity. Therefore, when system failures are involved in such complex systems, the effects of the related safety issues can also be more serious, thereby causing in the worst case irrecoverable hazards on both human being and properties. This fact can be witnessed in the recent rail systems accidents. In general, the accidents can be attributed to the systematic failure or the random failure. The latter is due to the aging or unsatisfied quality of the parts used in implementation or some unexpected external cause that would otherwise result in accidents whereas the former is usually related to incomplete systems design. As the systems are becoming more complex, so are the systematic failures. The objective of the paper is to study an approach to solving the systematic failure. To do so, at first the system design process is augmented by the functional safety activities that are suggested in the standard IEC 61508. Analyzing the artifacts of the integrated process yields the traceability, which satisfies the requirements for reduction of systematic failure as provided in ISO 26262. In order to reduce systematic failure, the results are utilized in the conceptual design stage of systems development in which systems requirements are generated and functional architecture is developed.

심부전 환자와 가족 돌봄제공자를 위한 다이애딕 중재에 관한 체계적 고찰 (Dyadic Interventions for Heart Failure Patients and Their Family Caregivers: A Systematic Review)

  • 김다영;김선희;박은주;손연정
    • 중환자간호학회지
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    • 제14권3호
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    • pp.113-127
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    • 2021
  • Purpose : This systematic review was conducted to identify which dyadic intervention could be implemented for heart failure patient-family caregiver dyads to improve patient and/or their family caregivers outcomes. Method : Eleven databases were searched from their inception to July, 2021. This review considered any randomized controlled trials that evaluated the effectiveness of intervention including heart failure patient-family caregiver dyads. Two reviewers independently evaluated the methodological quality using the Cochrane Collaboration's tool for assessing risk of bias and extracted details of the included studies. The studies included in this review were not suitable for meta-analysis and therefore the results were presented as a narrative summary. Results : Six studies including 900 dyads were included and mainly primary family caregiver of patients was spouse. Majority of dyadic intervention were focused on psychoeducational intervention excepting one study on mobile health intervention. All studies included in this review focused on patients' outcomes compared to family caregivers' outcomes and dyadic outcomes. Individual interventions improved quality of life among heart failure patients and their family caregivers in two articles. The overall quality of selected articles was low. Conclusions : This study provides moderate support for the use of a dyadic intervention to improve quality of life among heart failure patients and their family caregivers. More rigorous high-quality studies investigating interventions to meet the needs of patient and family caregivers in heart failure care are needed.

경사제의 다중 파괴모드에 대한 신뢰성 해석 (Reliability Analysis of Multiple Failure Modes of Rubble-Mound Breakwaters)

  • 이철응
    • 한국해안·해양공학회논문집
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    • 제20권2호
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    • pp.137-147
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    • 2008
  • 다중 파괴모드에 대한 경사제 제체의 시스템적 안정성을 신뢰성 이론으로 해석하였다. 먼저 경사제의 안정성과 관련된 네 개의 단일 파괴모드에 대한 신뢰함수가 수립되었다. 각각의 단일 파괴모드에 대한 AFDA 신뢰성 해석 모형이 개발되었으며, CIAD(1985)의 결과와 비교하여 만족스럽게 검증하였다. 단일 파괴모드에 대한 신뢰성 해석에서는 파괴확률 뿐만 아니라 파괴확률에 영향을 미치는 각 확률변수들의 영향계수를 산정하였다. 한편 경사제의 다중 파괴모드에 대한 신뢰성 해석을 수행하기 위해 세 가지, 일차해석법, 이차해석법 그리고 PNET, 해석법이 적용되었다. 해석 결과에 의하면 일차해석법은 파괴확률을 과다 추정하는 경향이 있다. 따라서 다중 파괴모드를 해석할 때는 각 파괴모드간의 상관성을 고려할 수 있는 이차해석법이나 PNET 해석법을 이용하는 것이 바람직하다. 마지막으로 파괴모드간의 상관성에 기인하는 파괴확률의 추가적인 발생 가능성을 다중 파괴모드 해석을 통하여 확인할 수 있었다.

A Systematic Literature Review Towards Service Oriented Architecture Adoption from 2009 to 2015

  • Niknejad, Naghmeh;Ghani, Imran;Hussin, Ab Razak Che;Jeong, Seung Ryul
    • International journal of advanced smart convergence
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    • 제7권3호
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    • pp.79-91
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    • 2018
  • Service Oriented Architecture (SOA) has appeared as an absorbing architectural approach that empowers the available systems to reveal their performance in the act of services, without creating important changes to the systems. This approach, due to its flexibility of adoption, has been widely recognized as an appropriate approach for implementing in organizations by many scholars and practitioners. Though, there are many studies that depict success factors of SOA; at the same time a few minor cases of failure has also been reported in the literature. In spite of the availability of rich material on SOA (in general), there is no systematic literature review on the potential aspect of SOA adoption factors. Hence, this article presents a systematic review of existing studies related to the SOA adoption and its success and failure factors from 2009 to 2015. The principle purpose of the study is to bring forward the existing issues and share our findings with researchers. Moreover, the findings of this paper would help IT experts in organizations to concentrate on the key factors highlighted in this study, so that they could decide whether it is advisable to adopt SOA or not in their context.

Factors Associated With Failure of Health System Reform: A Systematic Review and Meta-synthesis

  • Mahboubeh Bayat;Tahereh Kashkalani;Mahmoud Khodadost;Azad Shokri;Hamed Fattahi;Faeze Ghasemi Seproo;Fatemeh Younesi;Roghayeh Khalilnezhad
    • Journal of Preventive Medicine and Public Health
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    • 제56권2호
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    • pp.128-144
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    • 2023
  • Objectives: The health system reform process is highly political and controversial, and in most cases, it fails to realize its intended goals. This study was conducted to synthesize factors underlying the failure of health system reforms. Methods: In this systematic review and meta-synthesis, we searched 9 international and regional databases to identify qualitative and mixed-methods studies published up to December 2019. Using thematic synthesis, we analyzed the data. We utilized the Standards for Reporting Qualitative Research checklist for quality assessment. Results: After application of the inclusion and exclusion criteria, 40 of 1837 articles were included in the content analysis. The identified factors were organized into 7 main themes and 32 sub-themes. The main themes included: (1) reforms initiators' attitudes and knowledge; (2) weakness of political support; (3) lack of interest group support; (4) insufficient comprehensiveness of the reform; (5) problems related to the implementation of the reform; (6) harmful consequences of reform implementation; and (7) the political, economic, cultural, and social conditions of the society in which the reform takes place. Conclusions: Health system reform is a deep and extensive process, and shortcomings and weaknesses in each step have overcome health reform attempts in many countries. Awareness of these failure factors and appropriate responses to these issues can help policymakers properly plan and implement future reform programs and achieve the ultimate goals of reform: to improve the quantity and quality of health services and the health of society.

수치해석을 이용한 현상학적 연성파괴 모사 기법 (A Numerical Ductile Failure Simulation Technique Based on Phenomenological Damage Concept)

  • 김낙현;오창식;민성환;김윤재
    • 한국압력기기공학회 논문집
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    • 제5권2호
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    • pp.27-34
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    • 2009
  • This paper proposes a simple numerical method to simulate ductile failure behaviors. The method is based on finite element analysis with a simple damage theory. To validate the proposed method, simulated results are compared with experimental data. Despite its simplicity, the proposed method well predicts experimental results systematic analyses are also performed to investigate the effect of the element size.

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소성가공에 있어서의 금형수명 (Tool life in Metal Forming Processes)

  • 최재찬;김병민
    • 소성∙가공
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    • 제3권2호
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    • pp.147-155
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    • 1994
  • The service life of tools in metal forming technology is to a large extent limited by wear and fatigue fracture of the active elements. This presents a basic request for tool cost minimization and reduction of extensive machine down time, caused by premature tool failure. Currents developments are dominated by steps to reduce the causes of tool failure. A main problem of forming technology remains the insufficient reliability of tools due to a large and incalculable life time fluctuation. Only a systematic investigation of the failure mechanisms and operational loading of tools can lead to future improvements in tool layout, that is optimization of tool usage.

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고장원인 확률을 이용한 FMEA와 고장진단 순서의 최적화 (A Study for FMEA and Optimization of Failure Diagnosis Sequence Using Probability of Failure Cause)

  • 송기태;김민호;백영구;이기서;김수명
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.749-757
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    • 2007
  • Recently, with increasing interested in improvement of operational reliability and the systematic maintenance activities, the RCM analysis has been applied and tried to lots of applicable industries. This study covers applying the probability of failure cause to FMEA, and proposes an analytical method for this. Also, the measures of quantitative classification for the result of failure cause probability are addressed. Based on the field data, this thesis presents an identification for causes and characteristics of failure, and reviews them periodically from the above methodologies. As using FMEA applied the probability of failure cause, we in the future can look forward to improvement of efficiency for failure diagnosis & inspection, and reliability.

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User Experience Validation Using the Honeycomb Model in the Requirements Development Stage

  • Kim, Neung-Hoe
    • International journal of advanced smart convergence
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    • 제9권3호
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    • pp.227-231
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    • 2020
  • Recently, the importance of user experience (UX) has been rapidly increasing. Its utilization is emphasized for development of systems, products, and services. User experience is widely used across industries including services, products, processes, society, and culture. Therefore, if it is unsatisfactory, it is likely to have a direct negative impact on the corresponding system, product, or service. The failure to analyze user experience causes significant damage to the project, which may lead to its failure or redevelopment; it is hence necessary to prioritize the verification of UX in the earliest stages of development. The requirements development stage, which is a preceding stage, is an appropriate stage for the verification of user experience because the identification of user needs is completed and prototypes can be implemented. In this paper, we proposed a systematic requirements development stage; it adds user experience verification activities to the requirements development stage, using the Honeycomb model, which is a widely used tool for verifying the overall UX. User experience verification was added to the existing requirements development activities, which consisted of three steps: model definition and requirements placement, discussions between external and internal stakeholders, and review by internal stakeholders. By easily validating the user experience through this systematic requirements development stage, we expect to minimize the damage to the project due to the failure of the user experience analysis and increase the possibility of success.

ISO14971 기반 FMEA를 이용한 중환자실내 인공호흡기 신뢰성 관리 (Reliability Management of Mechanical Ventilator in Intensive Care Unit Using FMEA Based on ISO14971)

  • 김현준;김원규;김태종;서지영
    • 대한의용생체공학회:의공학회지
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    • 제44권1호
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    • pp.19-24
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    • 2023
  • Due to the spread of COVID-19, many patients with severe respiratory diseases have occurred worldwide, and accordingly, the use of mechanical ventilators has exploded. However, hospitals do not have systematic risk management, and the Medical Device Regulation also provides medical device risk management standards for manufacturers, but does not apply to devices in use. In this paper, we applied the Failure Mode Effects Analysis (FMEA) risk analysis technique based on the International Standard ISO 14971 (Medical Devices-Application of risk management to medical devices) for 85 mechanical ventilators of a specific model in use in hospitals. Failure modes and effects of each parts were investigated, and risk priority was derived through multiplication of each score by preparing criteria for severity, occurrence, and detection for each failure mode. As a result, it was confirmed that the microprocessor-based Patient Unit/Monitoring board in charge of monitoring scored the highest score with 36 points, and that reliability management is possible through systematic risk management according to priority.