• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.240-245
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• 2015

The principal objective of this study was to investigate the antioxidant and synergistic effects of fruit and vegetable concentrates. Ten foods from two categories, including fruits (raspberry, blackberry, blueberry, acai berry, aronia, cranberry, wild berry, and red grape) and vegetables (spinach and cabbage) were combined in pairs. The antioxidant activity of the individual and combined samples was measured using DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and FRAP (ferric reducing antioxidant power) assays. Synergistic antioxidant activities of the combinations of cabbage and acai berry, and blueberry and cranberry showed the most significant (p<0.05) increase in the DPPH and FRAP assays, respectively. In addition, the combination of cabbage and red grape demonstrated significantly high synergistic interaction in both DPPH and FRAP assays (p<0.05). These results indicate the importance of strategic selection of foods and their composition ratio for maximum synergistic antioxidant activity.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.14-25
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• 2021

The purpose of this study is to explore what are the interactive factors of synchronous online education in university and identify the level of interaction. This study used mixed research method. As a result of the interaction level, it was recognized that face-to-face education could be more interactive than synchronous online education. Synchronous online education could have better interactive between instructor and learner, and among learners than asynchronous online education. Factors which influencing the interaction were as follows: small group activities and scaffolding, diversification of communication channels and integration of learner's question in learning content. Detrimental elements were distance felt between instructor and learners, low intimacy among learners, content-focused lecture, restrictions on non-verbal communication, unstable systems and misusing microphones. The necessary factors to promote interaction are planning interactive class activities, etc. Based on the results, it was to suggest what kinds of efforts are needed to make interaction more effective in terms of teaching and learning method & activity, tool & system, and environment.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.6
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• pp.78-83
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• 2002

A modified patched grid scheme has been developed and employed for and axi-symmetric unsteady Euler solver based on Roe's FDS to analyze the unsteady flow fields induced by a train and a tunnel. On this paper, the innovative zonal method, named hybrid dimensional approach, was proposed and applied to the train-tunnel interaction problems. The basic idea of this method is to maximize the efficiency of numerical calculations by minimal assumption of spatial dimensions. The hybrid dimensional approach, embedded in the present modified patched grid method, yielded high numerical accuracy as much as the fully axe-symmetric method. The hybrid dimensional approach is expected to reduce the huge computation time of the train-tunnel interaction problems especially in the cases of solving a long tunnel.

• Journal of the Korea Concrete Institute
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• v.23 no.1
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• pp.23-30
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• 2011

In this study, deterioration degrees of concrete were investigated at laboratory under seawater attack and cycling freeze-thaw, which are major durability performance deterioration factors of concrete. Deteriorations of mixed concrete using Portland & blended cement were examined by instrumental analysis of changes in relative dynamic modulus of elasticity and compressive strength. After 520 cycles of freeze-thaw, relative dynamic modulus of elasticity and compressive strength of concrete mixed with normal Portland and LHC over 75% showed relatively low resistance of approximately 44% of those values of SRC. Concrete replaced with 50% fine powder of blast furnace slag showed the most excellent freeze-thaw resistance among the tested blended cement concrete.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.413-418
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• 1991

When L, bulgurzcus KFCC 35462 and S. uvarum KFCC 32021 were mixed cultured in soymilk, gorwth of L. bulgaricus was stimulated with growth of S. uvarunz little affected. Cultured in soymilk singly, L. bulgaricus produced only 0.07%) of acids. S. uvarum, cultured singly, produced 0.40% of ethanol and 0.18% of acids. Mixed culture of both produced 0.27% of acids and 0.42% of ethanol. Thus. S. uvarurrz was not much affected in growth and ethanol fermentation by L. bulgariccus, while L, bulgarzcus was stimulated by Sacch. uvarunz in growth but not in acid fermentation.

• Journal of the Korean Geotechnical Society
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• v.17 no.5
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• pp.129-136
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• 2001

본 논문에서는 석탄회 매립지반의 액상화 가능성을 평가하기 위해 순수 모래시료와 더불어서 모래시료와 석탄회가 혼합된 모래시료에 대한 일련의 진동삼축실험을 변형률제어 방법으로 수행하였다. 실험결과 진동하중에 의해서 시료 내에 발생하는 간극수압의 크기는 작용하는 전단변형률의 크기에 심각하게 영향을 받고, 작용하는 전단변형률이 지반의 한계전단변형률 보다 작은 경우에는 진동수가 높은 조건에서도 간극수압이 발생하지 않음을 알았다. 또한 전단변형률이 약 0.1%보다 작고 한계전단변형률에 가까운 경우에는 순수 모래시료와 비교하여 본 논문에서 조사한 석탄회 함유율 범위 (10%~30%)의 시료에서 간극수압이 더 크게 발생하였다. 반면에, 전단변형률이 큰 경우에는 순수 모래시료에서 간극수압이 크게 발생하는 추세를 보였다. 반복 전단에 따른 간극수압의 발생량은 전반적으로 석탄회 함유율이 증가할수록 커지는 경향을 보였다. 이러한 결과를 근거로 해안이나 하천에 인접한 한계지 개발에 있어서 사질토에 석탄회를 혼합 매립하여 지반을 조성하는 경우에 액상화에 대해서 불안정한 지반이 될 가능성이 있는 것으로 판단되었다.

• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.306-312
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• 1977

A mixed culture of Candida tropicalis and Trichosporon cutaneum was carried out using a n-paraffin medium. The growth of C. tropicalis was markedly enhanced by the mixed culture with T. cutaneum which did not grow on n-paraffin. C. tropicalis extracellularly excreted free fatty acids as metabolic products of n-paraffin in the culture medium. T. cutaneum appeared to assimilate these free fatty acids which were growth inhibitors for C. tropicalis, threreby enhancing the growth of C. tropicalis.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.384-387
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• 2004

강원도 지역 탄산수에 대해 혼합에 의한 용존 희유원소의 거동특성 및 탄산염 침전물 형성에 따른 REE 분별작용을 살펴보았다. 탄산수들은 화학적으로 $Na-HCO_3형,\; Ca-Na-HCO_3형\; 및\; Ca-HCO_3$형으로 구분되며, 동위원소조성도 유형에 따라 명확히 구분되는 특징을 보인다. 지화학 및 동위원소 자료의 해석 결과, $Na-HCO_$형 탄산수는 지하심부에서 심부 기원 $CO_2$의 공급에 의해 형성된 반면, 다른 두 유형의 탄산수들은 $Na-HCO_$ 형 탄산수와 천부지하수 간의 혼합에 의해 생성되었음을 지시하였다. 탄산수 내 용존 REE 함량은 물 유형에 따라 변화하지만, ∑REE 함량은 TDS, pH, alkalinity, $\delta^{18}O$$\delta^{18}O$ 및 tritium 함량과 좋은 상관성을 보여주어, 천부 지하수와의 혼합된 특징을 나타내었다. Na-HCO$_3$형 탄산수의 용존 REE 패턴은 강한 HREE 부화를 보여주어 이른바 'S-shape'을 나타내는 반면, $Na-HCO_$ 형은 분산되어 있으며 LREE 부화를 보여주었다. $Ca-Na-HCO_3$형은 약한 HREE 분화 패턴을 보여주었다. 탄산수로부터 침전된 침전물과 침전물을 제거한 잔류물의 REE 패턴은 원 탄산수와 거의 유사한 형태를 보여주어, 탄산염 침전물과 잔류물 간의 REE 분별작용은 일어나지 않았음을 나타낸다.지 않았음을 나타낸다.

• Analytical Science and Technology
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• v.11 no.6
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• pp.413-420
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• 1998

The hydrophobic interaction has been studied on sodium naphthalene derivatives such as sodium 1-naphthaleneacetate (S1NA), sodium 1-naphthalenemalonate (SINM), sodium 2-naphthaleneacetate (S2NA), and sodium 2-naphthalenepropionate (S2NP) in $H_2O$-MeOH mixture solutions and in surfactant solutions. In $H_2O$-MeOH mixture solutions, the hydrophobic interaction was measured, and resulted in the red shift in emission spectra. In cationic surfactant, cetyltrimethylamonium bromide (CTAB) solution, the hydrophobic interaction was also observed by the red shift in absorption and emission spectra.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.288-294
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• 1997

Field and pot expeiments were carried out to evaluate the interaction between quinclorac and bensulfuron-methyl on growth of the rice plants(Oryza sativa L. cv. Choocheongbyeo) at 20, 45, 65 days-old stages. Quinclorac and bensulfuron-methyl showed antagonistic interaction at both stages, which were detected by the Chisaka's method at isobles of 10% growth inhibition. The antagonism indices were -0.63 and -1.67 at 20 and 65 days-old seedling stages, respectively. Leaf-rolling of rice occurred when quinclorac was applied at 600g ai/ha or more at 20 days-old seedling stage, while it occured at the dose of 900g ai/ha at 65 days-old stage. Bensulfuron-methyl reduced plant height and dry weight as well as tiller production at both stages. Leaf-rolling of rice was reduced when mixture of quinclorac and bensulfuron-methyl was applied due to antagonism of the two herbicides. High temperatures increased the phytotoxicity of bensulfuron-methyl, while the phytotoxicity caused by quinclorac alone was not responsive to temperature. The antagonistic effect between quinclorac and bensulfuron-methyl increased at low temperature as tested by the Colby's method.