• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1043-1053
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• 1994

This study suggests a practical but rational approach for the development of reliability-based LRFD criteria for transmission towers under wind and ice loadings in Korea. Based on available statistical data on wind speed and icing on transmission lines in Korea, the design wind and ice loads are obtained by Monte Carlo Simulations. In the study, the AFOSM reliability method and an Importance Sampling Technique are used for the element and system reliability evaluation of actual transmission towers. Based on the selected target reliabilities, a set of load and resistance factors for the LRFD criteria are calibrated using the AFOSM and the code optimization technique.

• Computational Structural Engineering
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• v.6 no.1
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• pp.117-125
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• 1993

In general, the strength and stiffness of laminated composite cylindrical shells are very sensitive to the variation of slenderness parameters, some coupling-stiffness parameters, lamination angles, stacking sequence and number of layers. In this paper, the effects of these factors on the strength and buckling reliabilities of GFRP laminated cylindrical shells are investigated based on the proposed strength and buckling limit state models. As these factors have various and complicated effects on the strength and buckling reliabilities of GFRP laminated cylindrical shells, the results should be incorporated into the design formula such that optimum design technique and design code which provide uniform consistent reliability for balanced design in practice

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.3-4
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• 2007

본 논문은 전력계통의 보다 합리적인 신뢰도 운영을 실시하고자 근래 V&R Energy System Research에서 개발한 신뢰도 평가 프로그램인 POM과 EPRI에서 개발한 PRA를 이용하여 우리나라계통에 적용하여 성공적으로 얻은 다양한 사례연구 결과를 소개한다. 여기서는 PRA 프로그램을 우리나라 전력계통의 계획측면에서 활용방안을 모색하기로 하고 다음과 같은 몇 가지 사례연구에 주안점을 두고 실시하였다. 2008년도 우리나라 계통의 병입되는 당진화력 7,8호기의 신설에 따란 계통영향에 대한 신뢰도 지수 비교 순석과 2007년부터 2012년까지의 향후 6년간에 걸친 장기계통계획에 대한 우리나라계통의 신뢰도 지수의 변화를 비교 분석하는 등 계통계획측면에서의 활용방안의 타당성에 관하여 검토하였다.

• The Korean Journal of Applied Statistics
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• v.26 no.2
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• pp.321-333
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• 2013

Credibility theory is one of important theories in actuarial science to produce proper insurance premium. In this paper, new partial credibilities are proposed and introduced with widely accepted credibility theories such as rule of relative exposure volume, square root rule, B$\ddot{u}$hlmann credibility and B$\ddot{u}$hlmann-Straub credibility. Also, with credibilities estimated by current and newly suggested, the performance of the accuracy for estimating the risk is compared through real data analysis and we show that the newly suggested methods are improving the performance by reducing the error.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.193-200
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• 2010

Structural design requires simultaneously to ensure safety by considering quantitatively uncertainties in the applied loadings, material properties and fabrication error and to maximize economical efficiency. As a solution, system reliability-based design optimization (SRBDO), which takes into consideration both uncertainties and economical efficiency, has been extensively researched and numerous attempts have been done to apply it to structural design. Contrary to conventional deterministic optimization, SRBDO involves the evaluation of component and system probabilistic constraints. However, because of the complicated algorithm for calculating component reliability indices and system reliability, excessive computational time is required when the large-scale finite element analysis is involved in evaluating the probabilistic constraints. Accordingly, an algorithm for SRBDO exhibiting improved stability and efficiency needs to be developed for the large-scale problems. In this study, a more stable and efficient SRBDO based on the performance measure approach (PMA) is developed. PMA shows good performance when it is applied to reliability-based design optimization (RBDO) which has only component probabilistic constraints. However, PMA could not be applied to SRBDO because PMA only calculates the probabilistic performance measure for limit state functions and does not evaluate the reliability indices. In order to overcome these difficulties, the decoupled algorithm is proposed where RBDO based on PMA is sequentially performed with updated target component reliability indices until the calculated system reliability index approaches the target system reliability index. Through a mathematical problem and ten-bar truss problem, the proposed method shows better convergence and efficiency than other approaches.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.6 no.4
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• pp.53-60
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• 1986

This study is directed to propose a probability based LRFD design code, which could possibly replace the traditional USD provisions of the current code, based on the AFOSM reliability theory. The uncertainties of resistances and load effects for each R.C. structural elements are evaluated and adopted considering our practice, and a set of rational target reliability indices are selected based on the calibration with the reliability of the current R.C. design code and by considering the desired hierarchy of safety level. Then, a set of common load factors are chosen from the results of load and resistance factors which are computed by AFOSM method using the Rackwitz-Fiessler's efficient practical algorithm which is to transform the non-normal variables into the equivalent normal variables. It may be asserted that the proposed LRFD code for the R.C. building structures may have to be incorporated into the current RC. design codes as a design provision corresponding to the USD provisions of the current R.C. design code.

• Journal of The Korean Association For Science Education
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• v.41 no.1
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• pp.59-70
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• 2021

Ability to make informed decisions by critically evaluating media information on socioscientific issues (SSI) is one of the crucial elements of scientific literacy that citizens should obtain. This study aims to investigate how middle school students evaluated media information about socioscientific issues (SSI) when they faced two different types of information (i.e., numerical and empathic information). To achieve the aim, 96 middle school students responded to the questionnaires asking them to evaluate reliability and persuasiveness of SSI media information. The questionnaires consisted of two sets of newspaper articles on each SSI (pro-numerical/empathic, against-numerical/empathic). After reading the articles, the students evaluated reliability and persuasiveness of each article and wrote the reasons for their evaluation. The results were as follows: First, the students believed that news articles with numerical information were more reliable than the ones with empathic information in all SSI contexts. They tended to trust scientific evidence and data from numerical information, and real cases, societal problems, expressions, and values from empathic information. In addition, they evaluated their reliability based on the logic of information, accuracy of information, breadth and depth of data, and quantity and quality of sources both numerical and empathic information. Second, in case of evaluating persuasiveness of the articles, they focused more on the values that information contained, richness and logicality of the information, rather than the types of information, regardless of the type of information.

• 대학교육
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• s.79
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• pp.68-77
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• 1996

불행하게도 우리 대학의 경우, 자원의 사용에 대한 정보의 공시가 적정수준으로 이루어진 적이 없다. 정보의 공시란 다수의 의사결정자들이 합리적 판단을 할 수 있도록 하는 기능을 수행하기 때문에 사회적으로 가치를 갖는 것이다. 여기에서 우리는 재정 개혁을 위한 출발점으로 재무정보의 신뢰성 있는 공시를 제안한다. 최고의 지성집단인 대학이 자원 사용에 대한 보고책임을 게을리 하면서 부족한 자원을 공급해달라고 사회에 요청하는 것은 어불성설이다. 겸허한 자세로 정직.성실한 보고를 한 후 부족 자원 공급을 요청하는 것이 순리다.

• Defense and Technology
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• no.5 s.279
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• pp.38-45
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• 2002

하드웨어와 소프트웨어 개발비용을 독립적인 요소로 고려하지 않은 부정확한 무기체계의 소프트웨어 개발비용산정은 소프트웨어 개발사업 계획의 어려움을 가중시키며, 합리적인 무기체계 사업계획 수립을 곤란하게 할 수 있다. 무기체계의 소프트웨어 개발비용 산정에 대한 세부적인 방안 미비로 인하여 발생한 여러 문제점을 해결하고, 대국민, 대기업의 신뢰성 향상을 위하고 여러 가지 어려움에 봉착해 있는 방위산업체의 어려움을 해소하여, 비교적 정확하고 체계적인 무기체계 소프트웨어 개발비용 산정 방안이 제시되어야 한다. 따라서 이 글에서는 무기체계 소프트웨어 개발비용 산정에 적합한 개선방안을 제시하고자 한다.

• The Journal of the Korean dental association
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• v.22 no.11 s.186
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• pp.931-940
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• 1984

협회는 회원들의 유기적인 결속과 지속적인 보수교육을 평생교육으로 유도하여 신뢰받는 치과의사상을 구현하고자 지난 ‘83. 3. 17일 치과의사 보수교육지침서를 제정 하였읍니다. 이 지침서는 의료법으로 규정하고 있는 국내치과의사의 보수교육을 보다 간편하고 효과적으로 이수할 수 있도록 세부사항을 정하여 놓은 것으로서 보수교육의 미필로 법에 규정된 행정 처분을 받는 회원이 발생되지 않도록 하는 길잡이가 되고 우리 치과의사의 품위와 권익을 보호하는데 일익을 담당하게 될 것으로 믿읍니다. 본 지침서에 다소 문제점과 불편한 사항이 있드라도 감수하면서 문제점시정을 건의하고 개선하여 우리 모두가 바라는 합리적인 방향으로 발전해 갈수 있도록 협조를 하여 주시기 바랍니다.