• Journal of the Korean Geotechnical Society
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• v.29 no.10
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• pp.49-56
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• 2013

The use of geothermal energy has been increased for economic and environmental friendly utilization. Ground thermal conductivity and borehole thermal resistance are very important parameters in the design of geothermal heat pump system. This paper presents an experimental study of heat exchange rate of U and W type ground heat exchangers (GHEs) measured by thermal performance tests (TPTs). U and W type GHEs were installed in a partially saturated dredged soil deposit, and TPTs were conducted to evaluate heat exchange rates under 100-hr continuous operation condition. The heat exchange rates were also calculated by analytical models to estimate borehole thermal resistances and were compared with experimental results. It comes out that multi-pole and equivalent diameter (EQD) models resulted in more accurate agreement than shape factor (SF) model which is currently more often used.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.4
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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.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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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.

• The Mathematical Education
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• v.45 no.4 s.115
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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.

• Journal of Navigation and Port Research
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• v.32 no.7
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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.

• Korean Journal of Health Education and Promotion
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• v.27 no.3
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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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• v.4 no.4
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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.

• Journal of the Korea Convergence Society
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• v.10 no.5
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• pp.267-278
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• 2019

The objective of the current study was to engage in an in-depth discussion and analysis about the process of overcoming hardships in students that play varsity sports as student athletes and who grew up under incomplete family structures, To achieve this end, the current study conducts a narrative inquiry into the subjects, which found the following: First, in terms of improvement and expansion of interpersonal relationships, the student athletes were able to change their personalities to be more confident and active in their daily routines. Second, in forming positive emotions through playing sports, the student athletes were able to actively search for ways to overcome difficult situations and self-regulated their emotions. Third, in relation to improvement of problem-solving skills, the student athletes were able to find the most effective ways to overcome hardships caused by their broken family situations, in addition to exhibiting advanced problem-solving skills that enabled them to find courses that are most adequate for solving future problems.

• The Journal of Korean Society for School & Community Health Education
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• v.1 no.2
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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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• v.31 no.5
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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.