• 제목/요약/키워드: Reliability Prediction Specification

검색결과 16건 처리시간 0.023초

PRISM 신뢰성 예측규격서를 이용한 전자부품(PCB) 신뢰도 예측 (Reliability prediction of electronic components on PCB using PRISM specification)

  • 이승우;이화기
    • 대한안전경영과학회지
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    • 제10권3호
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    • pp.81-87
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    • 2008
  • The reliability prediction and evaluation for general electronic components are required to guarantee in quality and in efficiency. Although many methodologies for predicting the reliability of electronic components have been developed, their reliability might be subjective according to a particular set of circumstances, and therefore it is not easy to quantify their reliability. In this study reliability prediction of electronic components, that is the interface card, which is used in the CNC(Computerized Numerical Controller) of machine tools, was carried out using PRISM reliability prediction specification. Reliability performances such as MTBF(Mean Time Between Failure), failure rate and reliability were obtained, and the variation of failure rate for electronic components according to temperature change was predicted. The results obtained from this study are useful information to consider a counter plan for weak components before they are used.

형광등용 전자식 안정기의 신뢰성 모형 (A Reliability Model of Electronic Ballasts for Fluorescent Lamp)

  • 전태보
    • 품질경영학회지
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    • 제35권2호
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    • pp.27-36
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    • 2007
  • A study to build a reliability model of electronic ballasts for the fluorescent lamp has been performed in this study. We selected the widely being used specification, MIL-HDBK-217 for the study. We briefly reviewed the basic concepts of the electronic ballast with the selected reliability specification. We then developed a reliability model for the ballast using MIL-HDBK-217 and predicted the reliability. We further provided some guides which should be considered in future model development.

MIL-HDBK-217을 이용한 형광등용 전자식 안정기의 신뢰성 모형 (A Reliability Model of Electronic Ballasts for the Fluorescent Lamp using MIL-HDBK-217)

  • 전태보
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 2006년도 추계 학술대회
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    • pp.327-332
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    • 2006
  • A study to build a reliability model of electronic ballasts for the fluorescent lamp has been performed in this paper. We selected the widely being used specification, MIL-HDBK-217 for the study. We briefly reviewed the basic concepts of the electronic ballast with the selected reliability specification. We then developed a reliability model for the ballast using MIL-HDBK-217 and predicted the reliability.

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Mathematical Model of Shock Absorber for Performance Prediction of Automobile

  • Park, Jae-Woo;Lee, Jong-Heon;Kim, Jin-Wook
    • Journal of Advanced Marine Engineering and Technology
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    • 제27권4호
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    • pp.467-478
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    • 2003
  • Automotive shock absorber may not be regarded as only one(simple) damping machine because it is composed of many components, and shows non-linear damping characteristics. No matter how advanced form of shock absorber is developed, the oil shock absorber can not be neglected. because their structures are based on the oil shock absorber. Therefore it is essential to accurately analyze the dynamic characteristics of oil shock absorber. It stands mainly roi damper valve tuning which nowadays is still exhaustively done by means of ride work. In this study, damping mechanism and dynamic characteristics for oil shock absorber of twin tube type are analyzed, based on the mathematical model considering internal flow and pressure. For the reliability of numerical prediction. the database is constructed within the limit of adequate reliability. Finally, the programmed system that gives out necessary specification by inputting damping specification and tolerance is to be constructed.

항공기 전자장비의 신뢰성 예측 비교 연구 (A Study on Reliability Prediction Comparison of Aero Space Electronic Equipments)

  • 조인탁;이상천;김윤희
    • 산업공학
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    • 제25권4호
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    • pp.472-479
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    • 2012
  • Before an aircraft is delivered to customers, manufacturers have to verify required reliability for the aircraft. In usual, reliability of electronic equipments in military aircraft are predicted based on MIL-HDBK-217. But the specification has not been revised since 1995. Some alternatives including SR-332 and 217PLUS are suggested in this study. The processes and methods specified in MIL-HDBK-217 are compared with those of SR-332. Additionally, the predicted reliability of aircraft electronic equipment between usage data and field data are investigated using MIL-HDBK-217. The results show that predicted reliability of MIL-HDBK-217 is more conservative (underestimated) than that of usage data and field data.

L.E.O. Satellite Power Subsystem Reliability Analysis

  • Zahran M.;Tawfik S.;Dyakov Gennady
    • Journal of Power Electronics
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    • 제6권2호
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    • pp.104-113
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    • 2006
  • Satellites have provided the impetus for the orderly development of reliability engineering research and analysis because they tend to have complex systems and hence acute problems. They were instrumental in developing mathematical models for reliability, as well as design techniques to permit quantitative specification, prediction and measurement of reliability. Reliability engineering is based on implementing measures which insure an item will perform its mission successfully. The discipline of reliability engineering consists of two fundamental aspects; $(1^{st})$ paying attention to details, and $(2^{nd})$ handling uncertainties. This paper uses some of the basic concepts, formulas and examples of reliability theory in application. This paper emphasizes the practical reliability analysis of a Low Earth Orbit (LEO) Micro-satellite power subsystem. Approaches for specifying and allocating the reliability of each element of the power system so as to meet the overall power system reliability requirements, as well as to give detailed modeling and predicting of equipment/system reliability are introduced. The results are handled and analyzed to form the final reliability results for the satellite power system. The results show that the Electric Power Subsystem (EPS) reliability meets the requirements with quad microcontrollers (MC), two boards working as main and cold redundant while each board contains two MCs in a hot redundant.

상용 전기전자 부품의 품질등급 적용 방안에 관한 연구 (A Study on Method for Classifying Quality Levels of Commercial Electric & Electronic Parts)

  • 정다운;윤희성;곽초롱;이승헌;허만옥
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제12권1호
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    • pp.1-12
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    • 2012
  • The quality of a part has directly effect on part reliability. In the basis of MIL-HDBK-217F model, it is the determined rule that part's quality level should follow its nominal one written in its specification. If quality information is unknown, quality level of the part should be determined as 'Lower'. However, the prediction model is said to be short in reflecting parts applying 'state-of-the-art' technology and result in over-estimated failure rate by some reliability-related authorities or research institutes. In this study, the reliability prediction results by the model of MIL-HDBK-217F and Telcordia SR-332 are compared and analyzed to verify whether the statement is reasonable or not.

내고장 실시간 시스템의 신뢰도 향상을 위한 확률 명세 및 실행 예측 분석 방법 (An Analysis Methodology for Probabilistic Specification and Execution Prediction for Improving of Reliability of Fault-Tolerant Real-Time Systems)

  • 이철;이문근
    • 한국정보과학회논문지:소프트웨어및응용
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    • 제29권12호
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    • pp.926-939
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    • 2002
  • 시스템이 실행 중 다양한 환경 요인에 의해 발생할 수 있는 불확실성을 명세하기 위해 확률의 개념을 적용한 명세 방범이 요구되고 있다. 본 논문에서는 실행에 영향을 주는 많은 환경 요인들을 고려하여, 변화하는 실행 환경에서 시스템의 행위를 예측, 분석하기 위한 확률 정형 기법인 확률 추상 시간 기계(PATM:Probabilistic Abstract Timed Machine)를 제안한다. PATM에서는 확률에 영향을 주는 환경요인을 실행 도중 변경이 가능한 가변 확률 요인과 변경이 불가능한 고정 확률 요인으로 분류하고 있다. 시스템의 행위에 대한 분석은 PATM의 동적 실행모델인 확률 도달성 그래프를 통해서 이루어진다. 분석결과를 토대로 시스템의 동작 실패 가능성을 예측하고, 이에 영향을 미치는 가변 환경 요인을 변경하여 궁극적으로 시스템의 신뢰도를 향상할 수 있도록 한다.

FIDES의 품질 보증 인자에 대한 신뢰도 예측 비교 분석 (Comparative Analysis of Reliability Predictions for Quality Assurance Factors in FIDES)

  • 윤철환;서진욱;정성근;오현웅
    • 항공우주시스템공학회지
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    • 제18권2호
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    • pp.21-28
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    • 2024
  • 최근 뉴스페이스 시대라고 불릴 만큼 우주 산업 분야는 점점 커져가고 있으며, 초소형 위성의 중요성도 또한 커지는 추세이다. 초소형 위성은 주로 COTS 부품을 사용하며 우주급 부품에 비해 낮은 신뢰도를 가지고 있지만 개발 기간, 비용, 성능 측면에서 장점을 가지고 있어 사용성이 확대되고 있다. COTS(Commercial Off-The-Shelf)는 상용으로 판매되는 제품을 가리키며, 이는 특정 조직이나 프로젝트에서 직접 제작하는 대신 시장에서 구입하여 사용되는 것을 의미한다. 위성은 발사되는 순간부터 수리가 불가능 하기 때문에 신뢰도 예측의 중요성은 크게 작용한다. 근래에는 신뢰도 예측 시 부품에 대한 인자 뿐만 아니라 시스템 level에서의 신뢰도를 예측하는 것이 더 중요하게 적용되고 있다. 따라서 본 연구에서는 신뢰도 예측 규격인 MIL-HDBK-217F와 업데이트된 RiAC-HDBK-217Plus와 FIDES를 비교해 본다. 그리고 FIDES 예측 기준에서 다양한 산업 분야에 적용될 수 있도록 구성한 제조업체의 품질 보증 요소를 세분화하여 우주 산업에 적합한 점수가 반영될 수 있도록 하였다.

Mobile Resource Reliability-based Job Scheduling for Mobile Grid

  • Jang, Sung-Ho;Lee, Jong-Sik
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권1호
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    • pp.83-104
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    • 2011
  • Mobile grid is a combination of grid computing and mobile computing to build grid systems in a wireless mobile environment. The development of network technology is assisting in realizing mobile grid. Mobile grid based on established grid infrastructures needs effective resource management and reliable job scheduling because mobile grid utilizes not only static grid resources but also dynamic grid resources with mobility. However, mobile devices are considered as unavailable resources in traditional grids. Mobile resources should be integrated into existing grid sites. Therefore, this paper presents a mobile grid middleware interconnecting existing grid infrastructures with mobile resources and a mobile service agent installed on the mobile resources. This paper also proposes a mobile resource reliability-based job scheduling model in order to overcome the unreliability of wireless mobile devices and guarantee stable and reliable job processing. In the proposed job scheduling model, the mobile service agent calculates the mobile resource reliability of each resource by using diverse reliability metrics and predicts it. The mobile grid middleware allocated jobs to mobile resources by predicted mobile resource reliability. We implemented a simulation model that simplifies various functions of the proposed job scheduling model by using the DEVS (Discrete Event System Specification) which is the formalism for modeling and analyzing a general system. We also conducted diverse experiments for performance evaluation. Experimental results demonstrate that the proposed model can assist in improving the performance of mobile grid in comparison with existing job scheduling models.