• 한국초등과학교육학회지:초등과학교육
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• 제37권1호
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• pp.12-26
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• 2018

The purpose of this study was to investigate the characteristics of reasoning in which $3^{rd}$ grade elementary school students form ideas, design experiments, and interpret the results to solve problems in small group argumentation. For this purpose, 12 3rd-grade students' small group argumentations including experiments were observed. The researchers analyzed students' pre- and post-open questionnaires, field notes, and video recordings of small group argumentation. The results of the research are as follows. First, in the initial opinion formation process, a hasty unification of opinions and a transformation of inquiry problem occurred. In the design and execution of experiments, verification experiments and unplanned and arbitrary experiments were performed. They also selectively noticed or accepted claims, evidence, interpretation, and criticism. They could distinguish between the condition and the cause, but they were confused by using inaccurate terms and tended to keep the initial opinions when interpreting the results and drawing conclusions.

• 한국환경복원기술학회지
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• 제2권1호
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• pp.72-82
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• 1999

The objective of this study was to covering of vine the traffic noise barrier and analyse of their growth characteristics. For the purpose of the experiments, chosen were 28 plants. In January 1996 to December 1998, the nursery seedbeds on the Chonju Arboretum in Korea Highway Corporation were seeding and cutting with those species, and a few species were carried out Honam Highway field experiments. The results are summarized as follows ; The germination ratio of seedbed experiments were Wisteria floribunda(88%), Lonicera japonica(86%), Parthenocissus tricuspidata, Paederia scandens(85%), Celastrus orbiculatus(76%), Clematis terniflora var. denticulata(52%), Clematis mandshurica(44%) respectively. The rooting ratio of cutting experiments were Trachelospermum asiaticum var. intermedium(88%), Parthenocissus quinquefolia(87%), Trachelospermum asiaticum var. asiatica(85%), Kadsura japonica(82%), Hedera rhombea(81%), Euonymus fortunei var. radicans(83%), Trachelospermum jasminoides var. pubescens(80%), Lonicera japonica cv. Aureo-reticulata(80%), Trachelospermum asiaticum var. majus(78%), Euonymus radicans cv. Aureo-marginata(66%), in descending order. As a conclusion, this study shows that the traffic noise barrier was effected by Paederia scandens, Lonicera japonica, Parthenocissus quinquefolia, Wisteria floribunda, Parthenocissus tricuspidata in the field experiments and the others were necessary to maintainable management.

• 한국해양공학회지
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• 제34권4호
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• pp.253-262
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• 2020

This study provides a comparative analysis of experiments-based enhancements and sensitivity evaluations for the structural design of an automatic ocean salt collector under various load conditions. The sizing variables of the structural members were considered as design factors. The strength and weight performances were selected as output responses. The design of experiments used in the comparative study consisted of the orthogonal array design, Box-Behnken design, and central composite design. The response surface model, one of the metamodels, was applied to the approximate model generation. The design enhancement performance metrics, including numerical costs and weight minimization, according to the design of experiments, were compared from the best design case results. The central composite design method showed the most enhanced design results for the structural design of the automatic ocean salt collector.

• 한국과학교육학회지
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• 제9권2호
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• pp.29-45
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• 1989

The purpose of this paper is to study the operational skills of apparatuses in observation and experiments a point of view of the teaching-learning guidance of the middle school science. In order to understand the actual condition of the field learner, the achivment levels of learner have been investigated on the operational skills of apparatuses, observation and experiments through 1120 students of 16 middle schools. The results showed that there were large differences at each item and especially, in animate natural part(physics and chemistry), the handling ability was very low to average 33 percentage. By the result of analyzing the actual condition of the experiment and field science from the question of 114 science teachers who work in 40 middle schools in P distriet. it has been recognized that though the lessons through the experiments stimulate the motivation of learning, it couldn't be mamaged efficently because of all the educational conditions. And it was revealed that the major part of Experiment was performed not by student who is subjective in the course of learning but by teacher through experiments.

• Nuclear Engineering and Technology
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• 제55권3호
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• pp.1105-1117
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• 2023

In this study, the pressure drop behavior of single- and two-phase flows of air and water through the porous beds filled with uniform and non-uniform sized spherical particles was examined. The pressure drop data in the single-phase flow experiments for the uniform particle beds agreed well with the original Ergun correlation. The results from the two-phase flow experiments were analyzed using numerical results based on three types of previous models. In the experiments for the uniform particle beds, the data on the two-phase pressure drop clearly showed the effect of the flow regime transition with a variation in the gas flow rate under stagnant liquid condition. The numerical analyses indicated that the predictability of the previous models for the experimental data relied mainly on the sub-models of the flow regime transitions and interfacial drag. In the experiments for the non-uniform particle beds, the two-phase pressure loss could be predicted well with numerical calculations based on the effective particle diameter. However, the previous models failed to accurately predict the counter-current flooding limit observed in the experiments. Finally, we propose a relation of falling liquid velocity into the particle bed by gravity to appropriately simulate the CCFL phenomenon.

• 산업기술연구
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• 제27권A호
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• pp.85-94
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• 2007

This study, regarding curved channel, was performed to compare and analyze hydraulic characteristics and the speed of water and water level for left bank and right bank through hydraulic model experiments and numerical analysis. Real channels that had characteristics of curved channel were selected as objectives. In order to easily operate one and two dimensional numerical analysis and comparison for total 2.4Km model channel, measuring point was set up as 200m. HEC-RAS model was applied as one dimensional numerical analysis program and SMS model was used as two dimensional numerical analysis program. In respect of speed of water, the average speed of water for right bank recorded 8.33m/s in a model experiment and 3.08m/s, 8.57m/s were average speed of water for right bank in one dimensional and two dimensional numerical analysis. The average speed of water of two dimensional numerical analysis was quite similar to that of model experiments. Also, as for water level, maximum observational errors between one and two dimensional numerical analysis for right and left bank of model experiments were 0.66m, 0.84m and 0.28m, 0.48m for each. It was found that two dimensional numerical analysis had a similar result to hydraulic model experiments. Accordingly, from the result of this study, two dimensional numerical analysis should be used rather than one dimensional numerical analysis, when numerical analysis for curved channel is conducted.

• 동의신경정신과학회지
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• 제8권1호
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• pp.111-125
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• 1997

This study was done in order to investigate Oriental Medicine's meaning on stress, the stress is due to animal experiments.Methods:This research was done by animal experiments's results based on 41 animal experiment treatises carried out by 24 prescriptions about stress control. Each experiments were compared with same conditions, minimizing the experiments differences. The results were analyzed by p-value and Increas e·Decrease percentage of experiments result's numerical value. Results:1. Inquire into frequency in use of each stress stimulus and measuring items, the restriction stimulus stress and measuring the content of catecholamines are numerous.2. Significance of stress stimuluses based on experments's results is good by restriction stimulus.3. Oriental Medicine's meaning for stress is pathological phenomenon of Seven Emotion(七情). Stagnant the Energy(氣鬱), the Fire(火), Dam(痰), Lack of the general Blood thing(血虛), and reaction of an individual body.4. Inguire into the effects of frequency in use of experiments's Herb drugs, Herb Drugs of Tonifing the general Blood thing depend on stabilized Mind(補血安神), Circulated the Energy and Digest(理氣消導), Tonifing the general Blood thing(補血), Clearing the Mind(淸心), Removing the Dam(祛痰) are numerous.5. From a Sasang Medical point of view, experimental use of Herb Drugs are Soeum-in(少陰人) Herb Drugs are numerous.According to above results, it is considered that Herb Drugs of Tonifing the general Blood thing depend on stabilized Mind(補血安神), Circulated the Energy and Digest(理氣消導), Tonifing the general Blood thing(補血), Clearing the Mind(淸心), Removing the Dam(祛淡), and Soeum-in(少陰人) Herb Drugs are used to prevent stress and related diseases.

• 대한화학회지
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• 제51권1호
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• pp.93-100
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• 2007

이 연구의 목적은 중학교 과학 교과서에 제시된 ‘철과 황의 혼합물과 화합물 성질 비교 실험'의 문제점을 분석하고 개선책을 제시하는 것이다. 이를 위하여 9학년 과학 교과서에 제시된 실험 방법을 분석하고, 교과서에 제시된 실험 방법에 따라 중학교 과학을 담당하고 있는 40명의 현직 교사에게 실험을 수행하게 한 후 문제점을 분석하였다. 자극적인 기체 발생으로 인한 거부감, 자성 비교를 이용한 혼합물과 화합물의 구별 실패 등의 문제점이 개선된 개선 실험과 대안실험을 제시하였다. 제안된 2가지 실험을 10명의 현직 화학 교사와 S중학교 3학년 60명에게 적용한 결과, 제안된 실험은 혼합물과 화합물의 특성 비교에 적합하며 개념 이해에 도움이 된다고 응답하였다.

• 대한기계학회논문집A
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• 제32권3호
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• pp.258-266
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• 2008

The conventional approximate optimization method, which uses the statistical design of experiments(DOE) and response surface method(RSM), can derive an approximated optimum results through the iterative process by a trial and error. The quality of results depends seriously on the factors and levels assigned by a designer. The purpose of this study is to propose a new technique, which is called a sequential design of experiments(SDOE), to reduce a trial and error procedure and to find an appropriate condition for using artificial neural network(ANN) systematically. An appropriate condition is determined from the iterative process based on the analysis of means. With this new technique and ANN, it is possible to find an optimum design accurately and efficiently. The suggested algorithm has been applied to various mathematical examples and a structural problem.

• 한국과학교육학회지
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• 제25권3호
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• pp.346-352
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• 2005

이 연구에서는 문제 해결을 강조한 탐구적 일반화학 실험을 개발하여 그 적용 효과와 학생들의 실험에 참여하는 태도에 미치는 영향을 알아보는데 목적을 두고 있다. 문제 해결을 강조한 일반화학 실험이 실험에 참여하는 태도 변화에 효과가 있었는데, 맹목적 참여자에서 비판적 참여자로 변화한 수가 실험집단에서 3배 가까이 많았다. 또한, 차별성 인식, 탐구 정도, 토론의 유용성 부분에서 유의미한 차이를 보였다.