• Journal of the Korean GEO-environmental Society
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• v.3 no.3
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• pp.53-63
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• 2002

Until recently the other attempts except linear elastic analysis using assumed elastic modulus had not been made in order to evaluate the settlement of the rock fill materials in Korea. Especially, it was almost impossible to predict the precise settlement of the breakwater structure made with dumped rubble stone. In this study, 3 sets of large scaled triaxial compression tests for porous basaltic quarry rocks were carried out and numerical simulation of those triaxial compression tests were performed applying non linear elastic model. Two stress-strain behaviors were compared to study the adaptability of hyperbolic constitutive model for the rubble stone. The results showed quite good agreements between the two stress-strain behaviors. Thus, the hyperbolic constitutive model is thought to be alternative approach evaluate the settlements of the loose rock-fill material.

• Journal of the Korean Geosynthetics Society
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• v.14 no.3
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• pp.43-51
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• 2015

In seasonal frozen areas which have a temperature difference in the winter and spring season like south korea, if stiffness reduction by repeated freezing and thawing occurs to slopes adjacent to private facilities or mountain slopes, safety factor is insufficient to design criteria and landslide could be occurs due to rainfall or snowfall. It can lead to large damage of human life and property. In this study, in order to examine the safety changes of mountain slopes by repeated freezing and thawing, soil samples series of SP and SM by USCS distributed in surface soil of mountain slopes were collected for specimens. Through the direct shear test, the characterestics of frozen soil shear strength were analyzed and by utilizing numerical methods, chracteristics of strength reduction of weathered granite soil according to repeated action of freezing and thawing, changes in the stability of the slopes when applying freezing and thawing of the soil samples were examined. As a result, the maximum shear stress decreased approximately 10%, and slope stability analysis confirmed that required safety factor is less than compare with the non-frozen samples.

• Journal of the Korean Geotechnical Society
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• v.15 no.1
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• pp.161-173
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• 1999

Settlement analysis based on oedometer test results with or without Skempton-Bjerrum's modification method ( widely used for practical purposes when estimating consolidation settlements of soft clay deposits) has shortcomings that it cannot simulate real stress states and deformation behaviors of soils in case that in-situ loading and deformation conditions are not 1-dimensional. In this study, the stress path method, reflecting various probable stress paths, was employed to normally - consolidated kaolinite samples by using automated triaxial testing device which can control stress paths automatically. From this experimental study, elastic, consolidation, secondary compression and pore pressure development - dissipation behaviors under various stress paths were analyzed and deformation characteristics of soft clays, which can be the basis of rational estimation of settlements, were studied. Also by comparing results of stress path tests with those of 1-dimensional consolidation tests, limitations and problems of conventional methods were clarified.

• Journal of the Korean Geotechnical Society
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• v.30 no.10
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• pp.45-54
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• 2014

Many studies have been made on investigation, design, explanation and treatments etc. to minimize slope failure. However, the problem is that failures of cutting slope and natural slope due to Typhoon and localized heavy rainfall are still not reduced. It is difficult to treat the problem by only strengthening the design standard. And it is very necessary to carry out design and safety analysis under the most suitable conditions considering foundation and rainfall characteristics. In this study, variations of safety factor were discussed from different aspects to investigate the influence of different parameters of rainfall and analysis conditions. Rainfall and foundation conditions are supposed to be the most sensitive parameters to slope stability, and numerical analysis were performed by changing parameters of the two conditions. Rainfall behavior is based on the domestic statistical rainfall and foundation condition is selected as unsaturated soils. Study results show that, application of rainfall characteristics in different area and parameters of unsaturated soils are responding sensitively to variations of slope safety. Therefore, the input parameters should be fully examined when performing the practical design.

• 한국정보교육학회:학술대회논문집
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• 2010.08a
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• pp.243-249
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• 2010

2007 revised curriculum in primary schools by the educational programming should be carried out due to a number of practical constraints have been performed well. Elementary education program conducted by the EPL and Scratch Programming for haneunge was not long after the development of intuitive interface and blocks created using the syntax, contains multimedia elements, such as the benefits that can create artifacts due to the elementary education program is appropriate for. The researcher targeted the school for a semester, 4th year 12 weeks based on the results of scratch programming, programming by way of the Plan and the training and the results were analyzed. Scratch programming to increase student interest and enhance creativity and Formal help cultivate the scientific attitude can give you results. Scratch Programming for Elementary EPL Education is an effective lead of the students' prior knowledge or interest in sex by level of achievement because of the variation to allow individual learning needs to organize a program of study. And results in the production of sufficient thinking ahead and given time to discuss the purpose of education and programming will need to be alive.

• Information Systems Review
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• v.10 no.2
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• pp.179-194
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• 2008

To ensure continued existence, an organization must develop ways to share the knowledge that is possessed within the organization with the people who need, or who will need, that knowledge. Improving the efficiency of knowledge sharing is a highly desirable goal, but the issue of how best to motivate individuals to share their most valuable knowledge is not yet completely resolved. This paper aims to provide a sharing model on job related knowledge. Also, it intends to look for the factors that facilitate knowledge sharing among individuals in an organization. The research model is based on the technology acceptance model and it includes the perceived usefulness, perceived ease of use, attitude and intention to share constructs. Also, two external variables namely organizational culture and system quality were added. However, the actual use was excluded. In the research model, all hypotheses were found to be significant except one, which is the hypothesis that perceived usefulness will positively affect the intention to share.

• Journal of Elementary Mathematics Education in Korea
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• v.9 no.1
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• pp.39-64
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• 2005

The purpose of this study is to transform questions in the 7th curriculum to open-ended problems and exam students' attitude towards open-ended problems. Research questions in this thesis are as follows: First, to transform questions in the 7th curriculum to open-ended problems and apply to a class in the fourth grade D elementary school. Second, to find how students respond to learning mathematics with open-ended problems. As a result of this study, the following are identified. First, the students showed positive reactions towards learning mathematics with open-ended problems. Those experience with open-ended problems make student solve mathematics problems with interest and confidence. Second, both good and bad students in the math class show interest and concentration toward open-ended problem. But a few students show less interest towards those problems. Third, through discussion about problem-solving with open-ended problems, students take part in math class actively and show respect one another. Fourth, especially students show more interest and confidence towards the open-ended problems transformed from mathematics textbook and like the constructive open-ended problems.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.197-197
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• 2011

최근 들어 전력 사용량의 증가로 인한 화력발전소의 부산물인 석탄회 중 바텀애시와 각종 공공사업과 관련하여 해마다 현장발생토의 발생량이 지속적으로 증가하고 있는 추세이다. 바텀애시와 현장발생토사를 효과적으로 재활용하는 방법 중 유동성 뒤채움재를 개발하여 활용하는 방안을 모색하기 위한 연구이다. SP로 분류된 흙 현장발생토와 서천 화력발전소에서 발생하는 석탄회 중 입경이 0.9~1.5mm의 바텀애시만을 선별하여 현장발생토와 바텀애시의 비율을 7 : 3으로 변환한 최적배합을 선정하여 강재로 제작된 가로 80cm, 세로 60cm, 높이 90cm의 모형토조를 이용하여 실험을 진행하였으며, 사용상 지하 매설이 되는 관의 거동 특성은 확인하기 위하여 내경 30cm, 두께 8mm의 연선관 중 하나인 PVC관을 원형지하매설관으로 선정하여 배합을 타설하는 과정과 타설 후 7일간의 양생기간을 거친 후 차량하중으로 가정할 수 있는 하중을 가하여 원형지하매설관의 관외부에서 수직방향과 수평방향의 토압과 관내부의 수직 수평방향 변위 그리고 관 자체의 횡 종단 변형을 측정하여 원형지하매설관의 거동특성을 파악하였다. 타설시 지하매설관은 유동성 뒤채움재의 특성으로 인하여 시간이 지남에 따라 안정화되는 것을 확인할 수 있었으며, 최대하중을 3300kgf로 하여 하중 재하 후 지하매설관의 거동특성은 대체적으로 일반 모래를 사용하여 실험한 값보다 적은 변형 특성을 보이고 있으나 수평토압의 경우 일반적인 흙의 변형과 전혀 상이한 결과값을 보이는 경우도 있어 추가적인 실험 및 고찰의 필요하다. 본 실험에서 사용한 최적배합비 이외의 배합으로 같은 실험을 수행하여 바텀애시 량의 가감 및 재활용 재료인 폐타이어 고무칩등을 첨가한 실험을 계획하고 있으며 추후 실내시험과 모형실험을 토대로 유한요소해석을 추가로 시행하여 실험값과 해석값의 비교를 할 예정이다.

• Proceedings of the Korean DIstribution Association Conference
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• 2003.05a
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• pp.71-92
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• 2003

Specialty stores, which have been major channels of Korean cosmetic industry, are bringing out a lot of problems in current distribution channel systems because of its repeated depression of sales. Especially, inefficiency in distribution channel systems is caused by cannibalistic price-off competition between specialty stores, too many launchings of new products, excessive sales promotion, absence or surplus of stock, and so on. Using qualitative methods such as in-depth interview and group discussion, the authors attempt In diagnose fundamental problems of the cosmetic specialty store distribution channels in three viewpoints； achievement of goals, marketing flows in channels, and relationship management. In addition, this paper suggests core strategies for building up the competitiveness of both of the maker and the retailer, The competitive strategies are mainly about securing profitability of retailers, smoothening of marketing flows in channels, and building-up trustful relationships between distribution channel members.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6509-6517
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• 2014

This study examined the needs assessment of in-service education on teaching for school health teachers. The subjects of this study were 504 school health teachers, who were working in G-city and J-do. The data was collected from questionnaires of school health teacher's teaching from Nov. 9 to 23 2013. The data collected was analyzed by frequency analysis and a $x^2$-test. The conclusions were as follows. The first priority of the school health teacher's work is 'management of health problems' and the second is 'health education'. A difference was observed between the school levels (p< 0.01). The teaching methods mainly used on health care instruction were lecturing, discussion and practical training. The teaching materials of health care instruction mainly used were ppt, internet video, and textbooks. Most of health care teachers agreed to creativity education but they used creativity education less in practice. Most school health teachers want to in-service education on teaching and the contents of the course are creativity education or storytelling for new teaching.