• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.537-541
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• 2007

관거시설의 맨홀에서 수두손실이 과대해지면 관거의 통수능력이 저하되어 배수구역의 침수피해가 발생되고, 우수의 분출 시 맨홀 뚜껑이 유실되어 인명사고를 유발할 수도 있다. 특히 1990년대부터 국지성 집중호우에 의한 도심지역의 침수피해가 빈번히 발생하고 있는 현실을 감안할 때, 관거시설 내 맨홀에서의 수리적 에너지 손실에 대한 연구와 보다 구체적인 설계 기준의 제시가 요구되고 있는 실정이다. 이러한 점을 고려할 때, 도시지역의 우수관거 시스템의 우수 배제 능력을 증가시켜 도심지의 침수를 방지하기 위한 관거시설의 적정 설계 기준이 필요하며, 합리적인 설계 기준을 제시하기 위하여 맨홀 내에서의 수두 손실을 분석할 필요가 있다. 그러므로 본 연구에서는 일반적으로 설치되어 있는 직사각형 맨홀의 현장조사와 설계기준을 조사하여 수리 실험 장치를 제작하였다. 선정된 실험조건인 맨홀의 내부형상 변화와 하수도 시설기준상의 맨홀 내의 단차규정에 따른 수리실험을 실시하여 맨홀 내부의 흐름특성의 변화와 에너지 손실에 대하여 분석하였다. 또한 실험조건 변화에 따른 수두 손실계수를 산정하여 직사각형 맨홀 내부의 에너지 손실을 감소시키기 위한 방안을 제시하였다.

• Journal of The Korean Association For Science Education
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• v.33 no.2
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• pp.425-443
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• 2013

We developed problem-solving type inquiry learning programs reflecting scientists' research process and analyzed the activities of science-gifted high school students, and the understanding and the effects of the programs after implementation in class. For this study, twelve science-gifted students in the 10th grade participated in the program, which consisted of three different modules - making a cycloidal pendulum, surface growth, and synchronization using metronomes. Diet Cola Test (DCT) was used to find out the effect on the improvement of the ability to design experiments by comparing pre/post scores, with a survey and an interview being conducted after the class. Each module consisted of a series of processes such as questioning the phenomenon scientifically, designing experiments to find solutions, and doing activities to solve the problems. These enable students to experience problem-solving type research process through the program class. According to this analysis, most students were likely to understand the characteristics of problem-solving type inquiry learning programs reflecting the scientists' research process. According to the students, there are some differences between this program class and existing school class. The differences are: 'explaining phenomenon scientifically,' 'designing experiments for themselves,' and 'repeating the experiments several times.' During the class students have to think continuously, design several experiments, and carry them out to solve the problems they found at first. Then finally, they were able to solve the problems. While repeating this kind of activities they have been able to experience the scientists' research process. Also, they showed a positive attitude toward the scientists' research by understanding problem-solving type research process. These problem-solving type inquiry learning programs seem to have positive effects on students in designing experiments and offering the opportunity for critical argumentation on the causes of the phenomena. The results of comparing pre/post scores for DCT revealed that almost every student has improved his/her ability to design experiments. Students who were accustomed to following teacher's instructions have had difficulty in designing the experiments for themselves at the beginning of the class, but gradually, they become used to doing it through the class and finally were able to do it systematically.

• Journal of the Korea Concrete Institute
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• v.27 no.6
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• pp.625-632
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• 2015

In this study, a comparative analysis have been conducted to examine seismic reinforcement effect of a school building that is designed with a CBD (Channel Beam Damper) system supported by H-frame with existing non-seismic RC frame. As a result of experiment, seismic reinforcement specimen with CBD system showed hysteretic characteristics of a large ellipse with great energy dissipation ability and increased strength and stiffness, while non-seismic design specimen showed rapid reduction in strength and brittle shear failure at top and bottom of the left and right column. In addition, comparing the stiffness reduction between the two specimens, CBD system was effective in preventing the reduction of stiffness. Energy dissipation ability of specimen reinforced by CBD system was about 4.0 times higher than the non-reinforced specimen. Such enhancement in energy dissipation ability could be considered as the result of improved strength and deformation for further application in designing of seismic reinforcement.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.10-17
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• 2015

In this study, to examine seismic reinforcement effect of a school building constructed prior to application of seismic design, a Double I-type damper supported by wall was installed to perform comparative analysis on existing non-seismic designed RC frame. As a result of experiment, while non-seismic designed specimen showed rapid reduction in strength and brittle shear destruction as damages were focused on top and bottom of left and right columns, reinforced specimen showed hysteretic characteristics of a large ellipse with great energy absorption ability, exhibiting perfectly behavior with increased strength and stiffness from damper reinforcement. In addition, as a result of comparing stiffness reduction between the two specimens, specimen reinforced by shear wall type damper was effective in preventing stiffness reduction. Energy dissipation ability of specimen reinforced by Double I-type damper was about 3.5 times as high as energy dissipation ability of non-reinforced specimen. Such enhancement in energy dissipation ability is considered to be the result of improved strength and deformation.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.715-723
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• 2007

A displacement-based seismic design procedure was proposed for mid-to-low-rise steel moment frames. The proposed method was totally different from the current R-factor approach in that it directly uses available connection rotation capacity as a primary design variable. To this end, the relationship between available connection rotation capacity and seismic response modification (R factor) was established first; this relationship has been a missing link in current ductility-based design practice. A step-by-step displacement-based iterative design procedure was then proposed and verified using inelastic dynamic analysis.

• Journal of Engineering Education Research
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• v.14 no.3
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• pp.38-44
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• 2011

The purpose of this study is to provide the information of decision making that can be used to improve curriculum of engineering education by surveying and analyzing that educational needs of ${\bigcirc}{\bigcirc}$ university' engineering students about program outcomes. The conclusions of this study are as follows. First, it was found that engineering students surveyed valued much of the necessity of PO2(analysis experiment), PO3(design capability), PO6(teamwork) among program outcomes. In addition, it was found that engineering students surveyed thought their ability was low in PO3(design capability), PO4(problem solving), PO10 (knowledge of current events). Second, it was found that the order of educational needs about program outcomes was PO3(design capability), PO2(analysis experiment), PO1(knowledge application), PO5(practical ability), PO4(problem solving) which suggested that engineering students surveyed had high educational needs for engineering program outcomes. On the other hand, it was found that engineering students surveyed showed lower awareness of PO7, PO10, PO11 which had characteristics of humanities. It is necessary that systematic establishment of course completion system in basic design, element design and comprehensive design by giving weight to design education that aims to strengthen design capability should be made in curriculum of engineering education. It was found that there was considerable difference in educational needs about program outcomes especially in PO1(analysis experiment), PO4(problem solving), PO5(practical ability), PO6(teamwork) according to grade, gender and specialty and therefore this should be considered in designing curriculum. It is judged that operation of flexible education program should be arranged if learning achievement through regular curriculum Is limited.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1251-1255
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• 2006

도로 조건에 따른 빗물받이 유입구의 설치간격, 적정크기 및 관리 방안을 마련하여야 하며, 빗물받이 설계 시, 빗물받이 유입구의 통수능력을 저하시키는 빗물받이 유입구의 막힘 현상을 고려한 빗물받이 유입구의 합리적인 설계와 관리 방안을 마련하여 빗물 배제 능력을 향상시킴으로써 도시 홍수피해의 경감대책을 수립하여야 한다. 따라서 본 연구에서는 합리식을 이용하여 우수유출량을 계산하고, 빗물받이 차집효율 실험을 통하여 산정된 빗물받이 규격별 차집유입량 경험식을 이용하여 빗물받이의 차집유입량을 산정하였다. 막힘 현상을 고려한 빗물받이 유입구의 찻집효율 분석 실험을 실시하여 제시되어진 막힘 계수를 이용하여 빗물받이 유입구의 막힘 현상을 고려한 도로의 격자형 빗물받이 유입구의 설계 방법을 제시하였으며, Excel을 이용하여 간략하게 프로그램화 하였다. 제시된 설계방법은 실무에서 도로 조건의 변화와 빗물받이의 막힘 현상을 고려한 빗물받이 유입부의 설계에 사용 가능하다고 판단된다.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.30-30
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• 2011

국내의 내진설계 기준은 1988년에 처음 도입되었으며, 최근 점차 강화되고 있는 실정이다. 공동주택에 주로 적용되는 전단벽식 구조시스템에서 증가된 지진력에 저항하기 위해서는 벽량과 철근이 증가하게 되어 공사비가 상승하게 된다. 이러한 단점을 보완하기 위한 제진설계의 필요성이 대두되고 있는 실정인데, 기존의 제진장치는 주로 가새형 또는 벽체형을 대부분이라 평면계획에 제약이 있다. 따라서 전단벽식 구조의 공동주택의 제진설계 시에는 우리나라와 같은 중 약진 지역에 적합하고 저렴한 비용으로 충분한 내진성능과 평면의 가변성을 확보할 수 있는 댐퍼의 선택이 필요하다. 본 연구의 목적은 기존의 가새형 및 벽체형 제진장치의 국내 공동주택 적용시의 문제점인 평면의 가변성 확보에 유리하고, 수동형 제진장치의 장점을 추구할 수 있는 마찰댐퍼를 삽입한 커플링보 제진시스템의 내진성능을 조사하는 것이다. 내진성능을 평가하기 위해서 실대형 커플링보 실험체를 계획하고 제작하였다. 실험체는 2개로 구성되어 있으며, 하나는 기존의 철근배근 상세를 갖는 철근콘크리트 커플링보 실험체와 커플링보에 마찰댐퍼가 삽입된 실험체이다. 횡하중에 대한 성능을 평가하기 위해서 유사정적 반복가력실험을 실시하였다. 엑츄에이터로부터 실험체 상보의 가력지그를 통해 하중이 전달되도록 하였으며, 가력은 최초 0.25%의 층간변형각부터 변위제어를 통해 목표 층간변형각인 1.5% 이상까지 진행되도록 하였다. 실험결과, 두 실험체의 이력곡선과 에너지 흡수능력을 평가하였다. RC 실험체는 핀칭현상이 관찰되었고, 가력이 진행됨에 따라 커플링보와 벽체에서의 균열이 확산되어 종국적으로 취성적인 커플링보의 전단파괴가 발생하였다. 마찰댐퍼를 삽입한 실험체는 계획된 마찰거동이 잘 발휘되어 목표 층간변형각인 1.5%까지 이선형거동이 잘 나타났다. 최대 내력은 RC 실험체가 3배 이상 크지만, 누적층간변형각에 따른 에너지 흡수능력은 마찰댐퍼 실험체가 2배 이상 우수한 결과를 보였으며, 커플링보 및 벽체에서의 균열이 매우 저감되었다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2006.11a
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• pp.310-313
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• 2006

본 논문은 스마트 무인항공기를 개발하거나 획득시에 요구되는 전투실험 수행 중 지능화 정도에 대한 평가 및 실험방향을 제시를 위한 지능화 성숙도 모델을 제안한다. 먼저 표적탐색 소요검증 전투실험 절차를 제시하고, 지능화 정도를 4단계로 나누어 단계별 요구되는 지능수준을 제시한다. 분류된 지능수준별로 기술수준, 동작수준, 상호운용성 수준 영역의 4단계 각 수준별 요구 능력을 분석, 제시하여 지능화 정도를 측정할 수 있는 지능화 성숙도 모델을 설계한다. 마지막으로 표적탐색 소요판단을 위한 전투실험시 활용 가능한 중점분야를 지능화 성숙도 모델 영역별로 식별하고, 단계별 식별된 중점분야를 실험할 수 있는 전투실험 평가요소를 제시한다.

• Journal of Gifted/Talented Education
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• v.16 no.1
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• pp.43-60
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• 2006

This study mainly intended to investigate the relation between scientific inquiry and several entrance exam results of the gifted in earth science gifted program. The scientific inquiry was tested with their experiment designs. Entrance exams included achievement scores, creativity scores, problem solving, and oral test of high ability students. Student entrance scores were used to judge the level of students' competency in science. Recently students' ability of 'doing science' as measured by their designing experiments has been highly appreciated as a criteria of scientifically gifted students. One of the well known tests was Diet Cola Test developed by Fowler(1990). We used it as a test to figure out students' experiment design ability. We selected 22 gifted students in earth science. We compared their entrance test scores and Diet Cola Test results. Based on the comparison results we proposed several guideline of science education program for high ability students.