• 한국지반공학회논문집
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• 제29권10호
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• pp.49-56
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• 2013

최근 들어 경제적이고 친환경적인 에너지 활용을 위하여 지열에너지 필요성이 증대되고 있다. 지반의 열전도도(ground thermal conductivity)와 보어홀 열저항(borehole thermal resistance)은 지열 히트펌프 시스템(geothermal heat pump system)의 설계 과정에서 매우 중요한 변수이다. 본 논문에서는 일반 수직밀폐형에서의 U, W 타입의 지중 열교환기(ground heat exchanger)를 매립지 지반에 설치한 후 100시간 연속 운전 조건으로 현장 열성능 실험(thermal performance test)을 수행하였다. 또한 보어홀 열저항 산정 모델들을 이용하여 열효율을 산정한 후 이를 실험값과 비교하였다. 실험 결과 기존에 주로 적용되고 있는 shape factor(SF) 모델보다 multi-pole과 equivalent diameter(EQD) 모델이 계측값과 잘 일치하였다.

• 한국환경복원기술학회지
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• 제13권4호
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• pp.1-9
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• 2010

In response to climate change under a university level, this study has intended to find carbon-neutral campus development measures for Chungbuk National University (CBNU), which is composed of such facilities as education, research, and residential buildings. To reach this goal, we reviewed related literatures to find development measures for carbon neutral campus, employed a survey method asking students to show their preference and suitability toward provided measures, and statistical analyses to find appropriate measures using factor analysis. We have found the following results. First, based on literature review, we have identified several concepts regarding carbon-neutral city and has found the elements of carbon-neutral campus development. Second, we have drawn carbon-neutral campus development measures of CBNU through factor analysis. Finally, based on the characteristics and the present carbon-neutral campus conditions of the CBNU, we presented development measures.

• 한국해양공학회지
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• 제22권5호
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• pp.87-93
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• 2008

The objective of this paper is the investigation of the statistical properties of Vickers hardness (HV) of friction welded parts in nickel based super resisting steel, alloy 718 steel. First, we examine the statistical properties on the case of as-welded parts. Several Virkers indentations were made under same nominal conditions. This was repeated for three different applied loads, 100, 200 and 300g with a duration time, 10 second. The arithmetic mean of Vickers hardness in base metal (BM) materials is larger than that of HAZ in all applied loads. The measure of dispersion, that is, the coefficient of variation (COV) for BM and HAZ is decreased by increasing with the applied load. The distribution of Vickers hardness was not found to be symmetric type. The probability distribution of Vickers hardness was well followed Weibull distribution. The shape parameter and the scale parameter (characteristic hardness) are increased by increasing with the applied load, as both BM and HAZ.

• 한국수학교육학회지시리즈A:수학교육
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• 제45권4호
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• pp.439-457
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• 2006

This research was to understand the features of mathematization and didactical phenomenology, in a way that was not a routine calculation of equation, rather a complete comprehension by the reinventing historical principles of the equation. To achieve the purpose of this study, one-mate middle school student participated in the study. Interview and observation were used for collecting data during the student's performance. The results of research were: First, the student understood the mathematical concepts from a real life and developed the abstract concepts from it, which were very intimately related with his life. Second, the skill and formula definition were accomplished with the accompanying predicted and consequently derived mathematical concepts. Third, through the approach of using the history of mathematics, he became more interested in what he was doing and took lessons with confidence. Forth, the student performed his learning based on the historical reinventing principle under the proper guidance of a teacher.

• 한국항해항만학회지
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• 제32권7호
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• pp.537-542
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• 2008

A lot of cargo accidents occurred due to insufficient securing in the case of marine transportation. If the residual tension of securing rope can be predicted, it will be very useful in the handling of cargo securing work of operators. It was confirmed in the previous study that the fluctuation tension cf securing rope by oscillation could be predicted. In this paper, in order to the prediction of residual tension of securing rope, the experiments were carried out to measure the residual tension of securing rope under the oscillation and cyclic loadings. The residual tensions of two tests were in good agreement with each other. It can be predicted through the cyclic loading test in the estimated fluctuation tension without oscillation test by ship motion simulator.

• 보건교육건강증진학회지
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• 제27권3호
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• pp.1-12
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• 2010

Objectives: This study was to understand the essence and the meanings of smoking experience in female undergraduate students. Methods: Colaizzi's phenomenological method was used. Data were collected by in-depth interviews with six undergraduate female students. Field notes, recording under the subjects' agreement, and telephone interview were also used. Results: In the analysis, 131 significant statements, 15 themes, 7 categories emerged. The seven categories were as follows; 'the first smoking for change and adaptation', 'becoming a part of self', 'good friend without any reason', 'a bond with friends', 'gazing with bad eyes', 'unexpected guest without realizing it', 'willingness to smoke more'. Conclusion: The results of this study will help professionals to understand the smoking behavior of female undergraduate students. We should consider positive experience toward smoking in young women for considering to plan smoking cessation program.

• Journal of Electrochemical Science and Technology
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• 제4권4호
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• pp.119-124
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• 2013

The late Professor Su-Moon Park was an exemplary scientist, teacher and human being. It was my good luck and privilege to have had the opportunity of working under his guidance as a graduate student. Herein, I describe briefly the development and growth of some of the ideas in his career and how he and they influenced my career.

• 한국융합학회논문지
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• 제10권5호
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• pp.267-278
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• 2019

본 연구의 목적은 불완전한 가족 구성원의 형태로서 결손가정인 동시에 학업과 운동을 함께 병행하는 학생선수 들의 '역경극복 과정'에 대해 심층적으로 이야기하고 분석하는데 있다. 이러한 연구 목적의 달성을 위해 내러티브 탐구(narrative inquiry) 방법을 실시하였고, 그 결과는 다음과 같다. 첫째, 대인관계의 개선 및 확대와 관련하여 이들은 일상생활에서 자신 있게 행동하고 적극적인 성격으로 변화할 수 있게 되었다. 둘째, 즐거움을 통한 긍정적 정서형성과 관련하여 역경 상황의 개선을 위해 무엇을 해야 하는지 본인이 적극적인 탐색과 함께 스스로의 감정을 조절하였다. 셋째, 문제해결력의 향상과 관련하여 결손으로 인한 역경 상황에서 자신에게 가장 맞는 효과적인 방법의 발견과 미래의 역경상황에 적합한 방법을 선택할 수 있는 문제해결에 대한 능력이 향상된 것을 확인 할 수 있었다.

• 한국학교ㆍ지역보건교육학회지
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• 제1권2호
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• pp.87-104
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• 2000

The purpose of this study was to obtain the basic data as a improvement method through the fact-revealing concerning the drinking water management of school and utilization of student. The problems of the research are as follows: First, to investigate status of management of drinking water by area and school. Second, to investigate student's utilization of drinking water by area and school. 1,400 students was selected at 45 elementary and middle-high schools located in Kang-won province, and this study was constituted of two questionnaires(for school's questionnaire and student's questionnaire). The results was analyse through the frequency analysis, $x^2$-test on the basis of the above research problem by SPSS program. The findings of this research are as follows; 1) The Management of School Drinking Water First, the source of school drinking water was mostly piped water. Inspection of water quality has been fulfilled under four times a year, in the other hands, from the result inspection, the schools which was given inadequate determination was 22.2%. Second, reservoir cleaning and hygiene inspection failed far short of the regulations. Especially, reservoir cleaning was managed by exterior consignment industry not low-level officials. Third, school water drinking was the most supplied through the type of water purifier. Water purifier has been distributed to city-located and middle-high school highly, factually the water from water purifier was served with water cup. Fourth, the selection standard of water drinking manager showed slightly differently by school, accordingly there need to develope integrated system with the respective to its effective systematic management. Fifth, water cup was mostly treated by only water clear, which is to vindicate the problems concerning hygiene management. 2) Utilization of school student on Drinking Water First, Disbelief on drinking water of school student was very high. Especially, proportion of middle-high school student's disbelief of drinking water was higher than elementary school student, also girls higher than boys. Many of student have heard to don't drink water from around people. And there were showed meaningful differences by area and school. Second, It was showed many student recognize had to utilize water purifier, boiled water. However, they have still drunken the tap water or portable water from their home. Third, Many of student showed negative response with the respective to the management conditions of drinking water in classroom, There were showed meaningful differences by area and school. From the fact-revealing of water cup management, Students mostly answered to 'only water clear' and the answer of 'None use' or 'With personal cup' was higher. Fourth, In bad experience of Drinking Water, student mostly answered to 'occasionally' and there were showed meaningful differences by school. student's disease experience with school drinking water was few and there were showed meaningful differences by area and gender.

• Communications for Statistical Applications and Methods
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• 제31권5호
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• pp.467-485
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• 2024

Policymakers and educational researchers have grown increasingly interested in the extent to which study results generalize across different groups of students. Current generalization research in education has largely focused on the compositional similarity among students based on a set of observable characteristics. However, generalization is defined differently across various disciplines. While the concept of compositional similarity is prominent in causal research, generalization among the statistical learning community refers to the extent to which a model produces accurate predictions across samples and populations. The purpose of this study is to assess the extent to which concepts related to contextual generalization (based on compositional similarity) are associated with the ideas related to model generalization (based on accuracy of prediction). We use observational data from the Programme for International Student Assessment (PISA) 2015 wave as a case study to examine the conditions under which contextual and model generalization are aligned. We assess the correlations between statistical measures that quantify compositional similarity and prediction accuracy and discuss the implications for generalization research.