• 한국농공학회지
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• 제18권3호
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• pp.4171-4183
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• 1976

This study is to investigate the effect of some physical properties of soil on the compaction. The compaction effect depends upon various factors such as soil type, moisture content, gradation and compaction energy. In this study, with steady compaction energy, the relationships between maximum dry density and moisture content, gradation and consistency were analyzed by soil types. Some results obtained in this study are summarized as follows 1. Generally, the coarser the grain size, the bigger is the maximum dry density and the smaller is the optimum moisture content and its moisture-dry denisty curve is relatively steep. The finner the grain size, the smaller is the max. dry density and the bigger is the opt. moisture content and its moisture-dry density curve is less steep. 2. The relationship between max. dry density (${\gamma}$dmax) and opt. moisture content, void ratio, clay content, percent passing of No. 200 sieve, liquid limit and plastic limit can be represented by the equation ${\gamma}$dmax =ao+a1X(a0>0, a1<0) 3. The relationship between opt. moisture content (Wopt) and clay content, percent passing of No. 200 sieve, liquid limit and plastic limit can be represented by the equation Wopt=a0+a1X(a0>0, al>0). 4. The fact that maximum dry density of the compacted soil is decreased with the increase of the optimum moisture content in any types of soil tested, and the fact that optimum moisture content can be positively correlated with clay content, percent passing of No. 200 sieve, liquid limit and plastic limit of the soil, lead to the conclusion that clay content, percent passing of No. 200 sieve, liquid limit and plastic limit of the soil are direct factors in reduction of the maximum dry density of engineering soil.

• 생물환경조절학회지
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• 제17권4호
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• pp.273-282
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• 2008

수분 공급을 제한하여 수분 부족 스트레스를 처리한 상추식물에서 산화적 스트레스와 관련된 monodehydroascorbate reductase (MDHAR)의 활성도, 엽록소 함량, 과산화수소의 함량 등과의 상관관계를 조사한 결과, 생육배지의 수분의 함량이 감소함에 따라 식물체내 과산화수소의 생성량이 증가($R^2$=0.8851)하였으며, 수용성단백질 함량은 점차 감소($R^2$=0.9826)하는 경향을 나타내었다. 총 엽록소함량은 수분 부족 스트레스를 처리한 공시작물에서의 함량이 정상 생육시 보다 그 함량이 대체적으로 낮은 경향을 보였으며, 엽록소 a와 엽록소 b함량 변화도 총 엽록소의 함량변화와 비슷한 경향을 보였다. 그러나 총 엽록소에 대한 카로티노이드의 비율은 수분 부족 스트레스를 처리한 식물에서 정상생육 시 보다 더 높은 경향을 보였다. 수분 부족 스트레스가 진행됨에 따라 아스코브산의 함량은 정상 생육 시 보다 더 높은 경향을 보였으나 환원형인 디하이드로아스코브산의 함량은 수분 부족 스트레스를 처리한 초기에 정상생육 시 보다 더 낮은 경향을 보였다. MDHAR의 활성도는 사이토졸(cytosolic) 분획과 엽록체(chloroplastic) 분획에서 공히 크게 증가하였으며 MDHAR의 mRNA 전사 정도도 수분 부족 스트레스가 진행됨에 따라 크게 증가하였다. 수분함량이 감소함에 따라 MDHAR의 활성도가 크게 증가하였으며, 또한 과산화수소의 함량이 증가함에 따라서도 MDHAR의 활성도가 크게 증가($R^2$=0.9937과 0.8645)되어 수분 부족 스트레스로 나타나는 요인들과 MDHAR 사이에 밀접한 관련이 있음을 확인할 수 있었다.

• 한국심리학회지 : 문화 및 사회문제
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• 제28권4호
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• pp.627-659
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• 2022

본 연구에서는 초기 성인기 사람들의 과거 연애 관계에 대한 사고 정서가를 살펴보기 위해 Brenner와 Vogel(2015)이 개발한 PANERT(the Positive and Negative Ex-Relationship Thoughts Scale)를 번안하고 타당화하였다. 이를 위해 한국어로 번역한 PANERT를 전국의 20대 미혼 성인 남녀 337명을 대상으로 설문을 실시한 후, 주요 변인 간의 성차를 분석해 보았다. 이후, 문항 분석 결과에 따라 원문 12문항을 그대로 사용하여 한국판 PANERT를 구성하였다. 확인적 요인분석을 통해 긍정적 사고 정서가-부정적 사고 정서가의 2요인 모형(12문항)이 적합함을 검증하였고, 하위요인별 내적 합치도가 모두 높게 나타나 문항의 신뢰성이 확인되었다. 준거 관련 타당도 확인을 위해, 한국판 PANERT와 침습적 반추, 우울, 자기지각의 변화, 정적 및 부적 정서 반응과의 상관분석을 실시한 결과, 두 하위요인 모두 자기지각 변화를 제외한 모든 관련 구인과 상관관계를 보이는 것으로 나타났다. 마지막으로 두 요인이 정적 및 부적 정서 반응을 통해 우울에 어떤 역할을 미치는지 연구모형을 설정하여 매개효과를 살펴보았다. 이 과정에서 한국판 PANERT의 수렴타 당도와 변별타당도를 최종적으로 확인하였고, 구조모형의 간접효과 유의성을 확인하였다. 본 연구를 통해 한국판 PANERT는 총 12문항, 2개 하위요인으로 구성된 척도이며 초기 성인들의 이별 경험에 있어서 사고 정서가의 역할을 측정하는 도구로써 신뢰롭고 타당함을 확인하였다.

• 한국과학교육학회지
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• 제40권6호
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• pp.671-685
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• 2020

본 연구의 목적은 교과교육의 의미와 정체성을 탐구하는 한 가지 시도로써, 교과교육과 함께 이와 관련이 깊은 학문, 교과, 교과내용 간의 관계를 비판적으로 고찰하는 것이다. 본 연구에서는 먼저, 과학교육을 중심으로 '분리적' 관점의 기원을 살펴보고 이 관점이 학문, 교과, 교과내용, 교과교육 간의 관계에 대한 인식에 미친 영향을 살펴보았다. 그리고 '본질적-총체적' 관점에서 이들 간의 관계를 고찰하였다. 연구결과, '분리적' 관점은 학문, 교과, 교과내용, 교과교육 간의 유기적이며 전체적인 관계를 파악하는 데 한계가 있는 관점이라는 것을 알 수 있었다. 따라서 우리는 교과교육이 현재의 지평을 넘어 새로운 지평을 열고 모학문, 교과, 교과내용 등과의 온전한 관계를 회복하며 질적 발전을 이루기 위해서는 기존의 '분리적' 관점을 극복할 필요가 있다고 보았다. 한편, '본질적-총체적' 관점은 학문, 교과, 교과내용, 교과교육 간의 본질적으로 분리되지 않는 긴밀한 연관성을 드러냄으로써, 기존의 '분리적' 관점으로 야기된 문제들, 예를 들어 교원양성 교육과정의 파편화, 부실화 등의 문제를 해결하는 데 도움을 줄 수 있을 것으로 기대한다.

• 한국농공학회지
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• 제17권3호
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• pp.3815-3832
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• 1975

This study was made to investigate various engineering properties of earth materials resulting from their changes in density and moisture content. The results obtained in this study are summarized as follows: 1. The finner the grain size is, the bigger the Optimum Moisture Content(OMC) is, showing a linear relationship between percent passing of NO. 200 Sieve (n) and OMC(Wo) which can be represented by the equation Wo=0.186n+8.3 2. There is a linear relationship of inverse proportion between OMC and Maximum Dry Density (MDD) which can be represented by the equation ${\gamma}$d=2.167-0.026Wo 3. There is an exponential curve relationship between void ratio (es) and MDD whose equation can be expressed ${\gamma}$d=2.67e-0.4550.9), indicating that as MDD increases, void ratio decreases. 4. The coefficent of permeability increases in proportion to decrease of the MDD and this increase trend is more obvious in coarse material than in fine material, and more obvious in cohesionless soil than in cohesive soil. 5. Even in the same density, the coefficient of permeability is smaller in wet than in dry from the Optimum Moisture Content. 6. Showing that unconfined compressive strength increases in proportion to dry density increase, in unsaturated state the compacted in dry has bigger strength value than the compacted in wet. On the other hand, in saturated state, the compacted in dry has a trend to be smaller than the compacted in wet. 7. Even in the same density, unconfined compressive strength increases in proportion to cohesion, however, when in small density and in saturated state, this relationship are rejected. 8. In unsaturated state, cohesion force is bigger in dry than in wet from OMC. In saturated state, on the other hand, it is directly praportional to density. 9. Cohesion force decreases in proportion to compaction rate decrease. And this trend is more evident in coarse matorial than in fine material. 10. Internal friction angle of soil is not influenced evidently on the changes of moisture content and compaction rate in unsaturated state, On the other hand in saturated state it is influenced density. 11. Cohesion force is directly proportional to unconfined compressive strength(qu), indicating that it has approximately 35 percent of qu in unsaturated state and approximately 70 percent of qu in saturated state.

• 한국균학회지
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• 제1권2호
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• pp.1-7
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• 1973

양송이 수량을 지배하는 여러인자중에서 퇴비의 전질소 함량과 암모니아 잔류량이 양송이 수량에 미치는 영향을 구명하고자 본시험을 실시한 결과 다음과 같은 결론을 얻었다. 1. 퇴비의 전질소 함량과 양송이 수량간에는 y=1395+0.048x$(r=0.68^{**})$의 관계가 있었으며 전질소 함량이 높을수록 암모니아 잔류량도 증가하는 경향이었다. 2. 유기태급원은 무처리나 무기태급원에 비해 퇴비의 전질소가 증가되었으며 수량도 높았다. 3. 퇴비의 암모니아 잔류량과 양송이 수량간에는 $y=0.38086-0.011948x+0.00012x^2(r=-0.75^{**})$의 관계가 있었으며 안전다수확을 위해서는 0.03%(질소함량으로서)를 넘지 않아야 했다. 4. 유안의 사용은 암모니아 잔류량이 높았으며 양송이 수량이 낮은 반면 요소는 그 잔류량이 낮고 수량이 유안에 비해 현저히 높았다.

• 한국작물학회지
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• 제1권1호
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• pp.42-45
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• 1963

In a plant breeding program, an efficient selection of desired characters in a population is important. Generally, many agronomic characters in a given population are determined by polygenes and quantitatively inherited. In practice, the genetic relationship between two observed characters which are undoubtedly subjected to the environmental influence is difficult to identify. In recent years, many workers have attempted to understant the genetic relationship between characters in terms of genotypic correlation, and the knowledge thus gained should furnish many important and useful information for the planning of breeding, selection, and interpretation of the result. The genotypic correlation is the result of pleiotropy, linkage of genes(2, 3, 5, 6, 8) and natural or artificial selection(4). The purposes of this study were to estimate genotyric and phenotypic correlations between all possible pairs of nine characters. and to seek certain characters which may be useful as indicators of certain important agronomic characters. Weber and Moorthy(10), Johnson et al. (5) and Sheth(7) found that in general, the genotypic correlations were higher than the phenotypic correlations. Weiss et al. (11) obtained significant positive correlations between maturity and oil content, maturity and low protein content, and high protein content and low oil content. Weber and Moorthy(10) reported the positive genotypic correlations between flowering and maturity, yield and maturity, yield and plant height, yield and seed weight, and negative genotypic correlations between maturity and oil content, and oil content and seed weight. Johnson et al. (5) studied the genotypic and phenotypic correlations among 24 characters and concluded that selection based entirely on a long fruiting period, lateness, heavy seed, low protein, high oil and resistance to lodging would be effective in increasing yield. Sheth(7) found the following positive associations among characters; height and maturity, yield and lodging, low protein content and high oil content, and yield and low protein content. Hanson et al.(1) also reported high negative correlation between seed yield and protein content.

• 한국포장학회지
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• 제11권2호
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• pp.91-96
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• 2005

Determination of safety factor of corrugated fiberboard boxes used for agricultural products is very complicated process due to nature of living products. Moisture content is one of the most critical factors to determine overall physical strength of paper, so its influences on strength properties of corrugated board made from different raw materials must be quantified. The results obtained from the study were summarized as follows; 1. Results show a detrimental effect on bursting strength and compressive strength of liners with increasing relative humidity of environment and moisture content of liners. 2. The relevance of equilibrium moisture content at varying relative humidity levels was proved and its relationship was used as an important factor to estimate box compression strength. 3. Test results was statistically used for establish the relationship between relative humidity and moisture content of liners. Estimated compression strength of boxes at varying moisture content was similar to results of theoretical equations such as Kellicutt's. Further study could be carried out in order to determine a optimum safety factors of various corrugated board boxes for agricultural products.

• 수산해양교육연구
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• 제20권3호
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• pp.473-486
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• 2008

This study was to compare 'experiment' presentation types of middle school science textbooks of Korea, Japan, and China and to draw some implication for the improvement of Korean science textbooks. It analyzed the experiments from the unit 'Light' of science textbooks which is common content in all three different science textbooks. The researchers analyzed the experiments with two questions. First, how is the experiment organized? Second, what role does each element of the experiment is playing in the experiment setting? The findings of international comparative analysis of experiment presentation types of middle school science textbooks of three countries were as follows. First, the Korean and Chinese textbooks tended to present the experiments without enough information for the experimental process and method, whereas the Japanese textbook tended to present the experiment with detailed information for the experimental method and process. Second, whereas the Korean and Chinese textbooks tended to have a loosened relationship among pre-experimental content, experiment, after-experiment content, the Japanese textbook tended to have an organic relationship among pre-experimental content, experiment, after-experiment content.

• 한국식품조리과학회지
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• 제15권5호
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• pp.475-482
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• 1999

This study was carried out to prepare green tea by traditional roasting process, Kujeungkupo, and to determine its sensory characteristics. The carotenoid content in green tea was increased by roasting and reached 1,317 mg/100 g by Kujeungkupo. Of all carotenoids, the contents of lutein and $\beta$-carotene were 1,170 mg/100 g and 111.1 mg/100 g, respectively. The total cathechin content in green tea was 14.57 g/100 g after 9th roasting. The more the number of roasting the little contents of cathechin in green teas. Of all cathechin, epigallocathechingallate was the highest(6.80g/100 g) followed by epicathechingallte and epicathechin. total cholrophyll content was 141 mg/100 g of green tea. The free sugar content in Kujeungkupo green tea wet 2.18 g/100 g, of which sucrose comprised 46% (1.01 g/100 g). The color value ($\Delta$E) of Kujeungkupo green tea was 16.25. In sensory evaluation, sweet taste was the highest in green tea roasted 3 times and the flavor was best in that roasted 5 times. The sweet and astringent tastes of green tea had negative relationships with a and b values. The content of cathechin in green tea had a negative relationship with sweet taste and a positive relationship with astringent taste.