• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1308-1309
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• 2015

자력발전소 계측제어시스템은 과거의 아날로그 설비에서 디지털설비로 개선되고 있으며, 신규로 건설되는 발전소에서는 모든 시스템이 디지털화 되었다. 디지털설비는 하드웨어와 소프트웨어, 통신기능이 통합된 매우 복잡한 설비이며, 기존 하드웨어를 중심으로한 신뢰도 분석방법으로는 신뢰도를 확인하는데 한계가 있다. 따라서 본 논문에서는 기존의 신뢰도 분석방법의 한계를 극복하기 위하여 신뢰도 검증설비를 구성하여 다양한 시나리오에 의한 장기 종합시험을 수행하는 방식으로 신뢰도를 보증할 수 있는 방법과 구성들을 제시한다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.5
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• pp.437-443
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• 2014

Engine is one of the most important parts in a rocket for completing its mission successfully. In this paper, we provide a methodology for estimating reliability and development cost of a liquid rocket engine newly developed. To estimate reliability, a baseline engine is selected considering factors whose effects on reliability are unquantifiable. Then reliability of a baseline engine is adjusted to reflect the effect of factors that can be modeled quantitatively. Using the previous Transcost engine cost expressed in terms of mass and the number of hot firing tests, the engine development cost is reexpressed in reliability and thrust requirements. Finally, a numerical example is given to illustrate the application of the methodology to a turbopump rocket engine using staged combustion cycle with LOX/LH2 propellant.

• Electronics and Telecommunications Trends
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• v.15 no.3 s.63
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• pp.42-49
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• 2000

소프트웨어 검증에 사용되는 신뢰도 평가를 위한 기초 고장데이터를 수집하는 시스템 시험 방법과 소프트웨어 종합화에 고려되어야 할 사항들에 대해 제안한다. 그 외에 ATM 교환시스템 개발에서 얻은 경험을 정리하여 차세대 시스템 개발의 소프트웨어 품질 향상과 신뢰도 평가에 활용되도록 하였다.

• The Journal of Korean Association of Computer Education
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• v.9 no.6
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• pp.11-18
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• 2006

The purpose of this paper is to draw problems from analyzing "General Computer" questions of Career Searching Section in the College Scholastic Ability Test in 2005 and 2006 and to offer some suggestions about them. For the qualitative research, this paper analyzed content validity. For the quantitative research, this paper analyzed item difficulty and item discrimination by using Bayesian 1.0 based on 2-parameter item response model and this paper analyzed item reliability and distracters by using Testan 1.0. By analyzing "General Computer" questions, this paper would like to improve the quality of items and estimate item difficulty. Therefore, "General Computer" questions could be suggested as materials for developing reliable and discriminative questions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.11A
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• pp.987-994
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• 2005

Most of the proposed SRGMs are required to perfect debugging based on removal of defect as soon as the detection of defects in system tests. But the detected defects are corrected after few days as a fixed time or induced new fault in software under the imperfect debugging environments. Solving these problems, we discussed that the formal software reliability model considered testing-effort for the fault detection and correction of software defects, and then using this model we have estimated of the software reliability closed to practical conditions.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.273-276
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• 2008

A Through Bulkhead Initiation Module(TBIM) has been designed which guarantees the seal property without using O-ring. The TBIM works as the shock wave generated by a donor charge transmits to the acceptor charge. The structural safety of TBIM housing has been calculated via modeling analysis, and the ignition performance has been proved by 10 cc closed bomb test. The reliability analysis has been made using Probit method on the base of performance test results. According to the reliability analysis the bulkhead thickness of TBIM which is the most important design parameter has been determined.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.831-836
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• 1998

원자로 격납건물은 그 기능적 중요성 때문에 건설종료후 반드시 원자로 가상사고를 가정한 조건에 대해 구조적 건전성을 입증하여야 한다. 본 논문은 이러한 요건에 따라 수행된 월성 3호기 원자로 격납건물 구조건전성 시험(SIT : Structural Integrity Test)의 개요와 결과를 분석한 것으로 시험결과 월성 3호기는 설계시 고려한 허용범위내에서 거동하였으며 사고시 압력하중이 큰 경수로형 원자로와 달리 시험기간중 외기 온도 변화에 민감한 변화를 보인 것으로 확인되었다. 아울러 시험결과의 정확한 평가를 위해서는 시험전 충분한 기간동안 온도변화가 계측되어야 하며, 계측기 출력의 안정화가 계측성과의 신뢰도를 높이는 필수인자임이 확인되었다.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.838-839
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• 2008

실제 가정 및 공장에서 많이 사용되고 있는 저압 차단기는 안전성 및 성능의 신뢰성이 가장 중요한 제품이다. 이와 같은 저압 차단기의 성능평가를 위해서는 반드시 단락성능에 대한 검증이 이루어져야 한다. 단락성능을 검증하기 위한 단락시험설비의 측정시스템은 시험 신뢰도의 확보를 위해 주기적으로 교정하여야 하며, 그 결과를 저압 차단기의 성능평가 시에 적용해야 한다. 본 논문에서는 여러 가지 기기로 구성된 전압 측정시스템에서 각각의 계측기를 개별적으로 교정하지 않고, 전체 측정시스템을 하나의 기기로 간주하고 교정을 실시하는 방법을 통하여 전체 측정시스템에 대한 신뢰도를 확보하고자 한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.7
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• pp.1750-1758
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• 2015

This paper provides Bayesian methodology to estimate the reliability for guided weapons which are not continuously operating. The posterior distribution of subsystems and components becomes the next prior distribution. By analyzing the results of the sub-systems and components presented a method for estimating the reliability of the entire guided weapons. Bayesian methodology using existing test data of subsystems may be used to reduce the sample sizes.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.2 no.1
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• pp.32-42
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• 1991

Spielbergers Test Anxiety Inventory(TAI) is a self-report scale which can measure the cognitive(Worry) and affective(Emotionality) components of test anxiety separately. After having administered it to 756 Korean middle school students, it was concluded that some of the items of TAI were not relevant for Koreans as they were. They have been revised on the basis of informations collected from interviews with Korean students. The Korean Form of TAI(TAI-K) consists of 25 items for primary school- and 35 for high school students. The Cronbach's ${\alpha}$ of the TAI-K and the test-retest reliability were proved(${\alpha}=.90,$ r=.78 for primary school students ; ${\alpha}=.94,$ r=.85 for high school students). General Anxiety Scale and Self-esteem Scale were used to prove its validity. test Anxiety correlates with general anxiety positively. while it correlates with self-esteem negatively.