• Title/Summary/Keyword: Reliability verification

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Reliability Verification of Numerical Prediction Method on Pile Behaviour Characteristics using Field Static Loading Test (현장정재하시험을 이용한 말뚝 거동특성 수치해석 예측기법의 신뢰성 검증)

  • Nam, Hosung;Baek, Seungcheol
    • Journal of the Korean GEO-environmental Society
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    • v.18 no.9
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    • pp.11-18
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    • 2017
  • Numerical analysis method for prediction of pile behaviour characteristics has widely been used in detail design process before construction because field static loading test requires high cost. However, the reliability verification of numerical analysis of result is not permitted compare with field test. In this study, to verify the numerical analysis results, pile behaviour prediction was compared with field static loading test results. For exact analysis of interaction between pile and ground, soil investigation and in-situ test such as boring, SPT and bore-hole shear test were performed before pile static loading test. During the static loading test, pile behaviour characteristics were analyzed under every loading condition. After static pile loading test, numerical analysis was carried out under same condition with static pile loading test. In the numerical analysis, to apply same loading condition with each loading condition in the field test and to compare with between the results of numerical analysis, the field test results for reliability were verified with the results of numerical analysis.

A Knowledge - Base Verification of NPP Expert systems using Extended Petri Nets

  • Kwon, Il-Won;Seong, Poong-Hyun
    • Proceedings of the Korean Nuclear Society Conference
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    • 1995.10a
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    • pp.173-178
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    • 1995
  • The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential ewer checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP (Checker Of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompleteness in a knowledge base. The scope of the verification problem is expanded to chained errors, unlike previous studies that assumed error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainty factors.

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A Method of Knowledge Base Verification for Nuclear Power Plant Expert Systems Using Extended Petri Nets

  • Kwon, I.W.;Seong, P.H.
    • Nuclear Engineering and Technology
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    • v.28 no.6
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    • pp.522-531
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    • 1996
  • The adoption of expert systems mainly as operator supporting systems is becoming increasingly popular as the control algorithms of system become more and more sophisticated and complicated. The verification phase of knowledge base is an important part for developing reliable expert systems, especially in nuclear industry. Although several strategies or tools have been developed to perform potential error checking, they often neglect the reliability of verification methods. Because a Petri net provides a uniform mathematical formalization of knowledge base, it has been employed for knowledge base verification. In this work, we devise and suggest an automated tool, called COKEP(Checker Of Knowledge base using Extended Petri net), for detecting incorrectness, inconsistency, and incompletensess in a knowledge base. The scope of the verification problem is expanded to chained errors, unlike previous studies that assume error incidence to be limited to rule pairs only. In addition, we consider certainty factor in checking, because most of knowledge bases have certainty factors.

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A Study of BIM based estimation Modeling data reliability improvement (BIM기반 견적 모델링 데이터 신뢰성 향상을 위한 연구)

  • Kim, Yeong-Jin;Kim, Seong-Ah;Chin, Sang-Yoon
    • Korean Journal of Construction Engineering and Management
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    • v.13 no.3
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    • pp.43-55
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    • 2012
  • A methodology for BIM Quality Assurance in the construction industry is becoming increasingly an important issue to determine the reliability of BIM. However, the quality assurance of BIM is currently limited to check 3D models, such as clash detection and space layout while verification methods for disciplinary BIM results from structural engineering, mechanical engineering, and estimation do not exist yet. Particularly, in the BIM-based estimation mathematical equations to take off quantities are not clearly exposed so that the results are not quite accepted at practices. With the concept of reliability engineering defined in the manufacturing industry to improve reliability of outcomes of BIM-based quantity take-off, impacting factors that affect reliability of BIM-based quantity take-off were derived. It was found that the factors also include the modeling method and the features of a BIM tool. Therefore, this research aims to propose modeling and verification methods to improve reliability of BIM-based quantity take-off through the pilot test that was performed with commercial BIM tools and IFC-based BIM data.

A Study on the HALT & Life time Test of the Swirl Control Actuator (자동차 흡기유동제어밸브의 초가속수명시험 및 수명시험을 위한 신뢰성연구)

  • Kim, Sung Ok;Park, Sang Wook;Lee, Jin Sik
    • Journal of Applied Reliability
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    • v.14 no.1
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    • pp.59-70
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    • 2014
  • The requirements of reliability verification for new products and technology are increasing more and more in accordance with the trend of climate change prevention and GHG reduction technology, functional skills. SCA(Swirl Control Actuator) is the important part of a car intake manifold system. This device generates swirl that is mixing the fuel and air into the engine combustion chamber. This is to improve output for engine and reduce the emission for exhaust. In this article reliability assessment criteria for swirl control actuator for automobiles are established in terms of basic HALT and life time test.

Quantitative Reliability Assessment for Safety Critical System Software

  • Chung, Dae-Won
    • Journal of Electrical Engineering and Technology
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    • v.2 no.3
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    • pp.386-390
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    • 2007
  • At recent times, an essential issue in the replacement of the old analogue I&C to computer-based digital systems in nuclear power plants becomes the quantitative software reliability assessment. Software reliability models have been successfully applied to many industrial applications, but have the unfortunate drawback of requiring data from which one can formulate a model. Software that is developed for safety critical applications is frequently unable to produce such data for at least two reasons. First, the software is frequently one-of-a-kind, and second, it rarely fails. Safety critical software is normally expected to pass every unit test producing precious little failure data. The basic premise of the rare events approach is that well-tested software does not fail under normal routine and input signals, which means that failures must be triggered by unusual input data and computer states. The failure data found under the reasonable testing cases and testing time for these conditions should be considered for the quantitative reliability assessment. We presented the quantitative reliability assessment methodology of safety critical software for rare failure cases in this paper.

Reliability Assessment Criteria of Motorized Roller Conveyor (자체구동롤러 컨베이어의 신뢰성 평가기준)

  • Kim, Young-Joo;Go, Hee-Yang;Han, In-Sup;Kim, Yong Soo
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.24 no.5
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    • pp.521-529
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    • 2015
  • Owing to a reliance on imported products from Europe and Japan, the use of logistics equipment with poor energy efficiency coupled with high maintenance costs can lead to high operating costs for some domestic logistic centers. To lower their operating costs, the logistic centers use motorized roller conveyors. In order to commercialize this process, it is necessary to establish the test criteria and assess the reliability of the process. Currently, there exists no standard verification method to test the reliability of motorized roller conveyors. In this study, we propose reliability assessment criteria for a: i) reliability test, ii) environmental test, iii) safety test, and iv) lifetime test.

Verification of Reliability and Validity of Korean Version of Nurse's Job Crafting Scale (한국어판 간호사의 잡 크래프팅 측정도구의 신뢰도 및 타당도 검증)

  • Lee, Do Young;Je, Nam Joo;Kim, Yoon Jung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.3
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    • pp.339-350
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    • 2022
  • The purpose of this study was to develop and investigate the validity and reliability of the Korean Version of Nurse's Job Crafting Scale. The Korean version of Job Crafting was translated and reverse-translated, and its content validity was verified by experts. Statistics were processed using SPSS/WIN 21.0 and AMOS 21.0 programs through self-report questionnaires for 151 nurses. Exploratory factor analysis and confirmatory actor analysis were performed to verify construct validity, and model fit, concentrated validity, and discriminant validity were confirmed through the analysis results.To verify the criterion validity, correlations with each domain were obtained using the calling scale. For reliability verification, the internal consistency reliability coefficient was calculated and confirmed. Reliability of all 20 job crafting tools was Cronbach's α = .93, with .91 for factor 1 (Increase in structural work resources, 5 questions) and .87 for factor 2 (Increase in structural work resources, 5 questions). The factor 3 (Increase in social work resources, 5 questions) was .83. The factor 4 (Increasing challenging business needs, 5 items) was .87, which was satisfactory for the reliability of internal consistency, and the Korean Version of Nurse's Job Crafting Scale was found to be an applicable tool. This study shows that the Korean Version of the Nurse's Job Crafting Scale is a valid and reliable instrument to assess nurses in Korea.

Verification Strategy of IEC 61850 Communication Reliability for Constructing the Substation Automation System (변전자동화시스템 구축을 위한 IEC 61850 통신신뢰성 검증 방안)

  • Lee, N.H.;Jang, B.T.;An, Y.H.;Kim, B.H.;Shin, E.B.
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2009.10a
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    • pp.231-234
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    • 2009
  • IEC 61850 based substation automation system is operating under digital network with a number of IEDs and a HMI as relation of server and client. In case of IEDs, before implementing the system, all of the system integrators require IEC 61850 certificate from individual IED manufacture. Otherwise, there is nothing to verify IED for constructing substation automation system at the real substation. This paper shows verification strategy of IEC 61850 communication reliability such as association /release, report, dataset and four type control function.

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A Study on the Safety Plan for a Train Control System (열차제어시스템의 안전계획 수립에 관한 연구)

  • Kim Jong-Ki;Shin Duc-Ko;Lee Key-Seo
    • Journal of the Korean Society for Railway
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    • v.9 no.3 s.34
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    • pp.264-270
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    • 2006
  • In this paper we present a safety plan to be applied to the development of the TCS(Train Control System). The safety plan that can be applied to the life cycle of a system, from the conceptual design to the dismantlement, shows the whole process of the paper work in detail through the establishment of a goal, analysis and assessment, the verification. In this paper we study about the making a plan, the preliminary hazard analysis, the hazard identification and analysis to guarantee the safety of the TCS. The process far the verification of the system safety is divided into several steps based on the target system and the approaching method. The guarantee of the system safety and the improvement of the system reliability is fellowed by the recommendation of the international standards.