• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.216-221
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• 2011

An important problem in reliability analysis for repairable systems is to model the maintenance effect. The most of researches have assumed two extreme cases; one is perfect maintenance and the other is minimal maintenance. However, many of maintenances performed by domestic subway operators are imperfect maintenances which have the effect between both of two extreme cases. This article deals with the problem determining the imperfect preventive maintenance intervals based on failure data in units of the PDS(passenger door system) in Metro EMU. This paper deals with a case study on determining imperfect maintenance interval by using the level of maintenance effect through reliability analysis of PDS.

• Water for future
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• v.23 no.4
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• pp.487-497
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• 1990

The qualitative and quantitative prediction for the dispersion of thermal discharge from nuclear / fossil power plant, steel works etc. has significant roles for the cooling system. Design and environmental management. In this study, the several important physical properties for the behavior of a thermal discharge with strong turbulent and buoyant effects are described. The comparative evaluation between MIT and PDS models is carried out, which have the different model structures. In general, MIT and PDS models are commonly used to calculate the thermal discharge behavior with considering the ambient current and the angle of jet in an unstratified water body. The simulated results by these models have great discrepancies due to the different assumptions in modling.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10a
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• pp.255-261
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• 1998

본 연구는 물류산업에 있어 중심의 위치를 차지하고 있는 항만산업에서 컨테이너 터미널 운영 기업(Container Terminal Operating Company, TOC)들이 현재 처해 있는 경제 상황하에서 생존을 하기 위해 어떠한 모습으로 변화되어야 할 것인지, 그리고 21세기를 선도하기 위하여 TOC들이 반드시 갖추어야 할 역량이 무엇인가에 관한 체크리스트와 미래를 어떻게 대비해 나가야 하는가에 대한 로드맵(roadmap)을 제시하고자 한다. 먼저 국내의 컨테이너 터미널 운영 기업들이 현재 처해있는 환경에 대한 새로운 인식을 통해 컨테이너 TOC들의 목표를 재 설정하고, 차세대 컨테이너 TOC의 모델을 제시한다. 그리고 이에 대한 추진과제를 설정하고 이렇게 설정된 과제들 중에서 정보시스템 부분에 대한 실행 계획 및 요소 기술, 추진 전략 등을 제시한다.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1053-1057
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• 2008

본 연구에서는 산악형 강수 해석을 위해 제주도내 강우관측 자료를 이용하여 확률강우량 산정 및 고도와의 선형회귀분석을 수행하였다. 제주도내 강우관측 자료는 기상관서 4개소 및 AWS(Automatic Weather System, 자동기상관측소) 13개소의 자료를 활용하였다. 확률강우량 산정시 AWS 강우관측 자료는 AMS(Annual Maximum Series, 연 최대치 계열) 모형을 적용하기에는 자료기간이 충분하지 않으므로 짧은 자료기간에 적합한 PDS(Partial Duration Series, 부분 기간치 계열) 모형을 적용하였다. 따라서 본 연구에서는 PDS의 대표적인 분포형인 GPD(Generalized Pareto Distribution)를 적용하여 지속시간별 확률강우량을 산정하였다. 산정된 지속시간별 확률강우량과 고도와의 관계를 확인하기 위하여 선형회귀분석을 수행하였다. 회귀분석 결과 확률강우량은 고도가 증가함에 따라 선형적으로 증가하였다. 또한, 재현기간이 길어질수록 고도에 따른 확률강우량 증가율도 증가하였다. 다만, 재현기간과 관계없이 지속시간이 짧을 경우 확률강우량과 고도와의 선형 관계는 약해지는 것으로 나타났다.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.164-172
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• 2018

This study explores how to implement a learning experience-based professionalism program for a medical students and evaluates its program through effectiveness and usability test. This study aims to provide practical implications for experience-based learning in an undergraduate level. Seventy four first-year medical students enrolled in PDS1(Patient-Doctor-Society 1): professionalism, one-week block (30 hours), one-credit program based on a experience-based learning model. All of the students were given six learning themes and learning resources and supporting tools, and conducted stepwise learning activities; preparation, organization, sharing, reflection and evaluation of experiences. The effectiveness of learning was evaluated by comparing the pre and post results of student's self-assessment on 24 questionnaire items about professionalism. After the course, the students and instructors conducted a usability evaluation of the program through questionnaires or group interviews. Learners' self-assessment results of professionalism such as leadership, self-directed learning, professional attitude, and social accountability all showed significant differences between the pre- and post-test. Satisfaction of the program was distributed to 3.58~3.78 according to items. Instructors and learner interviews confirmed practical usability throughout the course design, implementation and students evaluation. The results of the study showed the feasibility of implementing learning experience-based professionalism program in medical school. This study provides practical implications to develope and evaluate the learning experience-based professionalism program in medical education.