• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.2
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• pp.9-19
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• 2002

Steel piers and concrete-filled steel(CFS) piers, in spite of reasonable strength, high ductility, small section, and fast construction, have not been considered as one of alternatives to RC piers even in the highly populated urban area where aseismic safety, limited space and fast construction are indispensably required. This paper, the first of two companion papers for the seismic performance of steel and CFS piers, tests steel and CFS piers under quasi-static cyclic loading to estimate their ductility and strength. Additional details such as rebars and base ribs are added to increase the ductility of a concrete-filled steel pier with minimum additional cost. Also, simplified numerical analyses using nonlinear spring and shell elements are examined for the estimation of the ductility and strength of concrete-filled steel piers and a steel pier. The result shows that concrete-filled steel peirs have higher energy absorption, i.e., ductility and strength than those of steel pier and increasing bonding between in-filled concrete and lower diaphragm, and the improved details of stress concentrated region would be important for the ductility and strength of a pier. Numerical results show that simplified modeling with nonlinear springs and shells has potential to be effective modeling technique to estimate the seismic performance of a concrete-filled steel pier.

• Journal of Korea Entertainment Industry Association
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• v.15 no.4
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• pp.217-227
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• 2021

The study aims to explore the rapidly changing university sports-related lecture environment from the perspective of professors and seek comprehensive and practical improvements in the online lecture environment for both professors and learners. In order to achieve the purpose of this study, six professors related to physical education at the university were selected as research participants, and in-depth interviews were used for about four months from September 2020 to December 2020. Examples of the problems, counterplans, and the improvement plans of professors who related to sports were shown as the results. First, the difficulties faced by professors have been divided into online and offline lecture problems, which are Internet and media possession, online lecture place amulet, professor-learner communication disorder, attendance verification and evaluation, COVID-19 infection, and face-to-face lecture place restriction since the outbreak of COVID-19. Second, professors' response to online and offline lecture problems was diversification of communication media, telecommuting, providing online learning videos, replacing and reinforcing practical classes, which were found to be somewhat lacking in government and school support systems. Finally, since the COVID-19 outbreak, Sports-related lecture's continuous problems and the professor's responses require the improvements such as government-level guidelines, university-level expansion of the venues for on- and off-line lecture, devising online lecture programs that enhance professor's convenience, and adjusting the number of participants for on- and off-line lecture.

• The Journal of the Korea Contents Association
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• v.9 no.10
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• pp.492-499
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• 2009

This research was conducted in order to know how influential the acknowledgment of factors such as the quality of educational contents and the conducting of off-line lectures is in terms of effective learning for leaners. Based on the satisfaction-importance model of the multi-attribute attitude model, this study would like to clarify the degree to which the quality of on-line contents of on-line education and the simultaneous conducting of off-line lectures influences one's learning attitude. On-line contents satisfaction will evaluated through the three categories: audio lectures, video lecture and WEI lectures, which make up the quality of on-line contents. We would also like to do a survey on the transformation of learning attitudes when on-line and off-line lectures were conducted simultaneously.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.475-479
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• 2008

West Java 지역에 위치한 인도네시아 Citarum 강 유역은 자국의 효율적인 수자원관리를 위하여 매우 중요한 요충지에 해당하며 최근 통합수자원관리 프로젝트(ICWRMP)를 통하여 활발한 투자와 개발이 행해지고 있는 곳이다. West Tarum Canal은 Jatiluhur 댐 하류단에 위치하여 자카르타시의 생공용수를 공급을 담당하고 있으며 저수지 방류수와 더불어 Cibeet 강, 그리고 Cikarang 및 Bekasi 강이 차례로 유입되면서 부족한 용수를 충당하게 된다. 건설초기에는 풍부한 수량과 양호한 수질을 확보하여 효율적인 용수공급이 이루어졌으나 주변지역 산업개발에 따른 인구 및 오염원 증가, 주민들의 무분별한 취수로 말미암아 이 지역의 수질악화가 날로 심각해지는 상황이다. 특히 Bekasi강은 도심부를 포함하고 있어 이 지역으로부터 배출되는 오염물질의 영향이 WTC의 수질에 가장 큰 영향을 미치게 된다. 수질모의는 Qual2E-Plus 모형을 이용하여 수행하였으며 이를 기반으로 시나리오를 구성, 오염정도가 심각한 Cikarang 강과 Bekasi강에 사이폰 시설을 도입 현재 운영중인 Weir 시설을 대체함으로써 얻을 수 있는 수질개선효과를 검토한 결과 Bekasi 강의 경우 10%, Cikarang 및 Bekasi강에 동시에 도입하였을 경우 12%의 수질 개선 효과가 있는 것으로 분석되었다. 한편 오염부하량이 가장 높은 Bekasi강 유역에 환경기초 시설을 도입함으로써 기대할 수 있는 수질개선효과는 처리시설의 효율에 따라 16% 에서 최고 48%에 달하는 것으로 분석되었다.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.267-274
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• 2014

Even though computer based college lecture management system was developed long ago and has been used ever since, developing perfect lecture management is not simple. The main objective of this system is to develop appropriate online lecture supportive management program suitable for college lectures. This system [ADLEMS] mainly focuses on the management of college database lectures, exams, and grades. This system supports management and grading of attendance, reports, quizzes, mid-term, and final exams. Exam management categorizes into multiple choice questions, essay questions, short answer questions, and SQL. Especially for SQL, division analysis was applied when developing grading system for more effective grade management. For essay questions and short answer questions, manual [hand] grading method was used. Every student can verify the grading process in person to alleviate the problems occurring during the grading process.

• Journal of the Earthquake Engineering Society of Korea
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• v.3 no.4
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• pp.33-46
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• 1999

In spite of 6.8 magnitude and the neighborhood of the epicenter, the steel moment frame survived after Northridge earthquake without collapse or casualties. However, following investigation revealed that there were severe damages at the column-weld interface of welded flange-bolted web (WFBW) steel moment connection, which was believed to be economic and safe from earthquakes based on experience and past tests. In this paper, this unexpected brittle fracture of the steel moment connection is explored using linear elastic fracture mechanics and post-Northridge tests. A method to predict the brittle fracture strength of the steel moment connection is proposed. Using this method, the failure mode of the WFBW connection and reduced beam section (RBS) connection are presented.

• Communications for Statistical Applications and Methods
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• v.18 no.1
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• pp.35-45
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• 2011

Some researchers insist that many students respond to the course evaluation surveys without sincerity and even without reading the questions. To analyze the pattern of student responses, the results of course evaluations for five semesters at Jeonbuk National University are reviewed. In mandatory course evaluations, 20% of the students marked the same option numbers to all questions regarding their lectures. In addition, consistent responses were over 50%. These results show that the university administration should reform the current course evaluation system in all respects.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1363-1367
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• 2007

낙동강 하류지점인 물금은 2003년${\sim}$2005년의 대부분이 부영양화의 기준을 넘고 있다. 본 연구에서는 WASP 모형을 이용하여 낙동강 하류에서 부영양화의 주요원인이 되는 영양물질과 결과적으로 나타나는 Chl-a 농도변화를 모의하였다. Chl-a의 농도모의를 위한 주요 입력자료로서 측정된 동물성 플랑크톤의 개체수가 입력되었다. 선정된 수질조사 지점은 낙동강 본류(왜관, 고령, 적포, 남지, 하남, 낙동강 하구둑)와 지류인 금호강, 회천, 황강, 남강, 밀양강이다. 수질모의 구간은 낙동강 본류(왜관${\sim}$낙동강 하구둑)와 지류인 금호강, 회천, 황강, 남강, 밀양강을 포함한 총 72개의 구간이다. 모형의 모의시간과 출력시간은 각각 1일로 하였다. 2003년의 자료를 이용하여 추정된 수질 매개변수들의 적합성을 확인하기 위해 2004년${\sim}$2005년의 수질자료와 유량자료를 이용하여 검증하였고, 입력된 매개변수와 기상 입력자료(유량, 수온, 일사량, 일조율)의 값을 중심으로 10% 씩 상하로 변화시켰을 때의 민감도를 분석하였다. Chl-a는 민감도분석결과 Chl-a의 성장률과 동물성 플랑크톤의 섭식률에 의해 영향을 많이 받았다. 인은 Chl-a에 영향을 주었지만 질소는 거의 영향이 없었다. 기상자료의 민감도분석결과 유량, 수온, 일조율, 일사량의 순서로 민감하게 모의 되었다. WASP 모형에서 동물성 플랑크톤 개체수의 입력 유 무에 따른 수질모의결과는 동물성 플랑크톤을 입력했을 때가 더 정확히 모의되는 것으로 나타났다.

• The Journal of the Korea Contents Association
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• v.10 no.12
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• pp.477-491
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• 2010

This paper aimed to understand current trends in online lectures for Korean SAT based on students' academic performances through a qualitative interview approach. In results, the highest academic performance group showed a good deal of interest and usage in online lectures. This group participants preferred private online lectures to public ones. However, the lowest academic group liked to use public online lectures. The middle academic groups who lived in an expensive area spent a lot of money for tutoring or attending private institutes rather than online lectures. Suggestions are: self-regulated learning is needed, public onilne lectures should have improved contents, and lastly, these online lectures are required to be connected with regular school curriculum.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.36-37
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• 2018

낙동강 하구역의 퇴적환경은 육성기원 퇴적물과 해성기원 퇴적물에 따라 다양하고 복잡하게 이루어진다. 낙동강 하굿둑이 건설된 이후의 퇴적환경 특성을 파악하기 위하여 해양공학회(2003)와 수자원공사(2016)의 자료를 수집 분석하였다. 2003년과 2016년의 표층퇴적물 분석결과, 낙동강 하구는 전반적으로 사질퇴적물이 우세하고 분급도가 양호하고 중앙입경 보다 조립질의 퇴적물이 우세하게 분포되는 것으로 나타났다. 기존 연구결과와 금회 연구결과로부터 2003년 이후 낙동강 하구 퇴적환경은 평형상태를 이루고 있는 것으로 판단되며, 낙동강 하굿둑 유출 유사량과 외해측 파랑에 의한 영향이 크게 받고, 창조시의 약화된 유속으로 인하여 니질퇴적물의 이동이 줄어든 것으로 판단된다. 또한, 니질퇴적물이 우세한 구간은 사주와 갯골 부근의 간사지로, 이로 인한 낙동강 하구역의 퇴적우세 현상은 지속될 것으로 판단된다