• Title/Summary/Keyword: High reliability

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A Study on Reliability Prediction for Korea High Speed Train Control System (한국형고속철도 열차제어시스템 하부구성요소 신뢰도예측에 관한 연구)

  • Shin Duc-Ko;Lee Jae-Ho;Lee Kang-Mi;Kim Young-Kyu
    • Journal of the Korean Society for Railway
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    • v.9 no.4 s.35
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    • pp.419-424
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    • 2006
  • In this paper we study on a method to predict and to demonstrate the reliability of the Korea high speed train control system in quantitative point of view. For the prediction of the reliability in train control system which is composed of electronic parts, Relax Software 7.7 automation tool is employed and MIL-HDBK-217 Handbook that is a standard for the prediction of the failure rate in electronic components is used. Mean Time Between Failure (MTBF) is predicted based on the failure rate of the subsystems, State Modeling and Markov Modeling method is used to express a reliability function of the train control system composed by hardware redundancy as a function of time. We propose a Reliability Test which is performed on the level of the subsystems and Failure Report, Analysing, Correction action system which use the test operation data to prove the predicted reliability.

A Study on Standardization of K-WPPSI-IV: Analyses of Reliability and Validity (한국 Wechsler 유아지능검사 4판(K-WPPSI-IV)의 표준화연구: 신뢰도와 타당도분석)

  • Park, Hyewon;Lee, KyungOk;Lee, Sang-Hee;Park, Minjung
    • Korean Journal of Childcare and Education
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    • v.12 no.4
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    • pp.111-130
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    • 2016
  • This study examined the reliability and validity evidence of the Korean version of Wechsler Primary & Preschool Scale for Intelligence(K-WPPSI-IV), which was standardized recently. Following the stratified sampling for Korean population in terms of region and maternal education level, 1,700 children aged 2.6~7.7 years were recruited for Korean norm development. The split-half reliability (N=1,700) was high(Fisher's z(.75-.89)) and test-retest reliability(N=100) was satisfactory ranging from .95 to .68. The inter-rater reliability(N=110) was very high(.96-1.0). Discriminant and convergent validities were revealed by correlational patterns among subtests and indices. Future studies are needed to extend both reliability and validity of K-WPPSI-IV by collecting data with a various sample group and a variety of instruments.

A Study on Evaluation of Insulation Reliability for High-Voltage Motor Stator Windings (고압 유도전동기 고정자 권선의 절연 신뢰성 평가에 관한 연구)

  • Hwang, Don-Ha;Shim, Woo-Yong;Kang, Dong-Sik;Kang, Do-Hyun;Kim, Yong-Joo
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1909-1912
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    • 2002
  • Recently, domestic electrical parts and materials without safety and reliability are avoided by consumers and introducing the product liability (PL) law. Therefore, the dependance on import product of electrical machines will be increased in the future. In this paper, high-voltage induction motor ensures reliance that can maintain the performance of machines for a long time. Furthermore, the test of reliability evaluation that predicts a remaining life and breakdown test of the stator winding are performed. Also, this paper introduces various reliability assessment tests for getting reliability of the stator winding insulation in high-voltage motor.

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Inorganic Salt Doped Soluble Polyimide Type Alignment Layer for Improving Panel Reliability and DC Image Sticking Properties

  • Lee, Tae-Rim;Roh, Seung-Kwang;Lim, Young-Nam;Kim, Kyeong-Jin;Shin, Hyun-Ho
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.672-676
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    • 2009
  • Polymide is widely used alignment material of recent commercial LCD panel structure. Generally, polyimide alignment material is classified soluble polyimide type and polyamic acid type with their main bond structure of solution state. specially, compared to polyamic acid alignment layer, soluble polyimide type alignment layer have excellent reliability during long term LCD driving cause of their high imidazation ratio(%), high voltage holding ratio(%) and low ion density. The other side, this type alignment materials has significant DC image stickicng side effect for using in-plane switching mode lcd structure cause of their slow DC discharging property. we applied inorganic salt to usual soluble polyimide type alignment layer and found out this technique had good DC image sticking property without any loss of reliability property in inplane switching LCD cell structure. This approach leads excellent DC image sticking property with maintaining high reliability property this approach confirmed improves an image sticking and a reliability simultaneously from the horizontality aligned LCD mode whose relatively bad image sticking property.

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The Introduction of the Final Proposal for the High-current Standard Measurement System (대전류 표준측정시스템에 대한 STL 최종방안의 소개)

  • Jeong, J.Y.;Shin, Y.J.;Kim, I.S.;Kim, M.K.;Lee, J.G.;Kim, M.H.;Lee, Y.H.
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.403-405
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    • 2003
  • 본 논문에서는 대전류 표준측정에 대한 STL TC의 Ad-Hoc Working Group의 최종방안에 대해 자세히 소개하여 이를 계기로 국내에서도 필요한 사전준비에 만전을 기하고자 한다. 향후 연속적으로 해야 할 업무, Shunt의 소유, 경비 지불방법 등에 대한 사항과 함께 우리나라 대전류 표준측정시스템의 구축절차를 제안하였으며, 이를 통해 대전류 측정에 있어서 국제표준과의 소급성을 확보할 수 있기 때문에 국내에서 시행하는 각종 시험에서 대전류 측정이 국제적으로 유효하게 될 것이다.

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A Study on the Technical Background of the Final Proposal for the High-current Standard Measurement System (대전류 표준측정시스템에 최종방안의 기술적 배경에 대한 고찰)

  • Jeong, J.Y.;Shin, Y.J.;Kim, I.S.;Kim, M.K.;Lee, J.G.;Kim, M.H.;Lee, Y.H.
    • Proceedings of the KIEE Conference
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    • 2003.11a
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    • pp.409-411
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    • 2003
  • 본 논문에서는 대전류 표준측정에 대한 STL TC의 Ad-Hoc Working Group의 최종방안에 대한 기술적 배경을 소개하여 이를 계기로 국내에서도 대전류 표준확보에 필요한 사전준비에 만전을 기하고자 한다. STL의 대전류 reference shunt 요구사항, 측정 불확도 및 각 시험소에서 교정하여야 할 사항 등에 대하여 검토하고, 우리나라 대전류 표준측정시스템의 구축필요성, 구축절차 및 방안에 대하여 기술한다.

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Seismic Reliability Assessment of Mid- and High-rise Post-tensioned CLT Shear Wall Structures

  • Sun, Xiaofeng;Li, Zheng;He, Minjuan
    • International Journal of High-Rise Buildings
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    • v.9 no.2
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    • pp.175-185
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    • 2020
  • Currently, few studies have been conducted to comprehend the seismic reliability of post-tensioned (PT) CLT shear wall structures, due to the complexity of this kind of structural system as well as due to lack of a reliable structural model. In this paper, a set of 4-, 8-, 12-, and 16-storey benchmark PT CLT shear wall structures (PT-CLTstrs) were designed using the direct displacement-based design method, and their calibrated structural models were developed. The seismic reliability of each PT-CLTstr was assessed based on the fragility analysis and based on the response surface method (RSM), respectively. The fragility-based reliability index and the RSM-based reliability index were then compared, for each PT-CLTstr and for each seismic hazard level. Results show that the RSM-based reliabilities are slightly less than the fragility-based reliabilities. Overall, both the RSM and the fragility-based reliability method can be used as efficient approaches for assessing the seismic reliabilities of the PT-CLTstrs. For these studied mid- and high-rise benchmark PT-CLTstrs, following their fragility-based reliabilities, the 8-storey PT-CLTstr is subjected to the least seismic vulnerability; while, following their RSM-based reliabilities, the 4-storey PT-CLTstr is subjected to the least seismic vulnerability

A Note on Improving Reliability in the Development of Weapon Systems (무기체계 개발단계에서 신뢰도 향상방안)

  • Choi, Chung-Hyun;Park, Sang-Eun
    • Journal of Applied Reliability
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    • v.15 no.1
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    • pp.1-5
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    • 2015
  • This note suggests three approaches to improve reliability in developing weapon systems. The high complexity of the weapon systems make it hard to analyze and predict of those reliability. Current situations of the reliability have been reviewed in terms of logistics support analysis (LSA), warranty policy, maintenance and development. Three suggestions are notified to improve the reliability considering the complexity of the weapon systems.

Evaluation of seismic reliability and multi level response reduction factor (R factor) for eccentric braced frames with vertical links

  • Mohsenian, Vahid;Mortezaei, Alireza
    • Earthquakes and Structures
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    • v.14 no.6
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    • pp.537-549
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    • 2018
  • Using vertical links in eccentric braced frames is one of the best passive structural control approaches due to its effectiveness and practicality advantages. However, in spite of the subject importance there are limited studies which evaluate the seismic reliability and response reduction factor (R-factor) in this system. Therefore, the present study has been conducted to improve the current understanding about failure mechanism in the structural systems equipped with vertical links. For this purpose, following definition of demand and capacity response reduction factors, these parameters are computed for three different buildings (4, 8 and 12 stories) equipped with this system. In this regards, pushover and incremental dynamic analysis have been employed, and seismic reliability as well as multi-level response reduction factor according to the seismic demand and capacity of the frames have been derived. Based on the results, this system demonstrates high ductility and seismic energy dissipation capacity, and using the response reduction factor as high as 8 also provides acceptable reliability for the frame in the moderate and high earthquake intensities. This system can be used in original buildings as lateral load resisting system in addition to seismic rehabilitation of the existing buildings.

The Estimation of Analytical Method for Axial Force-Moment Relationships of High-Strength Concrete Structures using Reliability Theory (신뢰성 이론을 이용한 고강도콘크리트 구조물의 축력-모멘트관계에 있어서의 해석방법에 대한 평가)

  • 최광진;장일영;송재호;홍원기
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.04b
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    • pp.447-454
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    • 1998
  • The main object of the study is that axial force-moment relationships for high strength concrete structures using reliability theory(Linear statstical method, Monte Carlo Simulation) including probability conception. And mean stress factors and centroid factors proposed to high strength concrete structures using reliability theory(Linear statstical method, Monte Carlo Simulation). Finally, The established experimental data for axial force-moment relationships are compared to the analytical data(data for Linear statstical method and Monte Carlo Simulation) for axial force-moment relationships in this analytical method.

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