• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.689-696
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• 2018

System grounding is applied to the neutral point of a power source to secure the from any abnormal voltage and/or grounding fault. System grounding, which is applied mainly in ships is an ungrounded and resistance grounded system. Vessels using the MV power system with 3.3kV, 6.6kV, and 11kV mainly adopt a high resistance grounding system among the resistance grounding systems. The ground fault accounts for 95% of all faults occurring in the electrical system and when a fault occurs, the line-to-ground voltage of the power system is increased excessively, which adversely affects the onboard insulation system. This study analyzed the variation characteristics of the line-to-ground voltage neutral point according to the degree of ground fault in a resistance ground system applied in vessels. For this purpose, the characteristics of the grounding system were first explained, and the modeling of the neutral point potential of the line-to-ground voltage of the resistance grounding system in the vessels was derived. Finally, this study examined how the line-to-ground voltage, line voltage, and neutral point change according to various variable environments through MATLAB simulations.

• Journal of Life Science
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• v.25 no.11
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• pp.1223-1229
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• 2015

Oryzalin is a dinitroaniline herbicide, which disrupts the arrangement of microtubules. Microtubules and microfilaments are cytoskeletal components that are thought to play a role in the sedimentation of statoliths and the formation of cell walls. Statoliths regulate the perception of gravity by columella cells in the root tip. To determine the effect of oryzalin on the gravitropic response, ethylene production in primary roots of maize was investigated. Treatment with 10^-4 M oryzalin to the root tip inhibited the growth and gravitropic response of the roots. However, the treatment had no effect on the elongation zone of the roots. An application of 10^-4 M oryzalin for 15 hr to the root tip caused root tip swelling. The application of 1-aminocycopropane-1-carboxylic acid (ACC), a precursor of ethylene, to the root tip also inhibited the gravitropic response. To understand the role of oryzalin in the regulation of the growth and gravitropic response of roots, ethylene production in the primary roots of maize was measured following treatment with oryzalin. Oryzalin stimulated ethylene production via the activation of ACC oxidase (ACO) and ACC synthase (ACS), and it increased the expression of ACO and ACS genes. Indole-3-acetic acid (IAA) played a key role in the asymmetric elongation rates observed during gravitropism. The results suggest that oryzalin alters the gravitropic response of maize roots through modification of the arrangement of microtubules. This might reduce the distribution of IAA in the upper and lower sides of the elongation zone and increase ethylene production, thereby inhibiting growth and gravitropic responses.

• Journal of Life Science
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• v.22 no.5
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• pp.681-686
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• 2012

Light, one of the environmental stimuli, is fundamental to the growth and development of plants. Red and far-red light are sensed using the phytochrome family of plant photoreceptors. To investigate the effect of light on root growth and gravitropism, we used the Arabidopsis phytochrome mutants grown in several light conditions. The root growth of $phyA$ reared in all light conditions except white light and was stimulated compared to the WT. The stimulation of root growth was obvious in $phyA$ grown in red light. On the other hand, the root growth of $phyB$ grown in all light conditions decreased, and the lowest rate of decrease was observed in $phyAB$ grown in white and red light. The gravitropic response of $phyA$ was stimulated compared to the WT when it was grown in all light conditions except far-red light. $PhyAB$ grown in all light conditions showed the inhibition of gravitropic response. The transcript level of ACS, one of the enzymes regulating ethylene biosynthesis, increased in $phyA$ grown in white and red light, but not in $phyA$ grown in far-red light. In conclusion, these results suggested that the $P_{fr}$ form of $phyB$ regulates the root growth and gravitropism.

• Applied Biological Chemistry
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• v.14 no.1
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• pp.35-41
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• 1971

Changes in fatty substance of hot pepper fruit during the after-ripening period were studied for both neutral and polar fatty substance. The results obtained from these studies are tabulated as follows; 1. Total fatty substance decreased as the after-ripening proceeded, while neutral fatty substance was least during the climacteric period. Polar fatty substance showed sudden drop in the amount during the post-climacteric period. 2. Fatty acid composition in neutral fatty substance showed that there is decrease in linoleic acid during the post-climacteric period, and in myristic acid and oleic acid respectively during the climacteric period. Stearic acid contents also drops sharply as after-ripening proceeds. 3. Value for saturates to unsaturates in and the amount of neutral fatty substance became least during the climacteric period, indicating that there is relationship between metabolism of neutral fats and climacteric rise. 4. Fatty acid composition of polar fatty substance showed that there is decrease in linoleic acid when after-ripening takes place whereas linolenic acid increases. These became reverse in the amounts after the climacteric period, suggesting that these changes may be useful to indicate true maturity of the fruits.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.305-308
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• 2002

선택적인 이온센서의 개발은 환경적, 생리학적, 의학적 중요성에 의해 높은 관심을 받고 있다. 지금까지 전기 화학적인 검출, 형광검출, 그리고 다른 광학적인 방법들에 근거한 매우 다양한 이온센서들이 연구되어 왔다. 금속이온들의 선택적인 결합은 음이온들이나 중성물질 보다 상당히 쉽게 결합하기 때문에, 금속이온 인식을 위한 형광 화학센서들의 개발이 일찍부터 이루어졌다. (중략)

• Horticultural Science & Technology
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• v.32 no.4
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• pp.484-492
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• 2014

We quantified the effects of the composition and concentration of fertilizer solutions on the growth and nutrient uptake of 'Maehyang' strawberry at the vegetative growth stage. Acid fertilizer (AF), neutral fertilizer (NF), and basic fertilizer (BF) with concentrations of 100 or $200mg{\cdot}L^{-1}$ based on N, were formulated and applied during the 100 days after transplanting, at which point crop growth and tissue nutrient contents were analyzed. The soil solutions were sampled every two weeks to measure the pH, EC and nutrient concentrations. BF was a more effective fertilizer compared to AF and NF for growth of 'Maehyang' strawberry when fertilizer concentrations were controlled to $100mg{\cdot}L^{-1}$. By contrast, the fresh and dry weights were greatest in the NF treatment when fertilizer concentrations were controlled to $200mg{\cdot}L^{-1}$. The tissue contents of N, P, and Na were 2.20, 0.51 and 0.10%, respectively, in the NF 200 treatment, and these were the highest among all treatments tested. The highest contents of K, Ca and Mg were 2.60% in AF 200, 0.95% in BF 200 and 0.45% in BF 100, respectively. During the fertilization period, the highest and lowest pHs were 6.13 in BF 100 and 4.92 in AF 200. The lowest EC was $1.376dS{\cdot}m^{-1}$ in BF 100 and the highest was $4.936dS{\cdot}m^{-1}$ in NF 200 treatments. The highest $NH_4{^+}$ concentrations in the soil solution occurred during the AF 200 treatment, followed by those with NF 200 and AF 100. When fertilizer concentrations were equal, AF treatment gave rise to the highest $Ca^{+2}$ and $Mg^{+2}$ concentrations, followed by NF and BF, until day 84 of fertilization. The BF treatments had the highest $NO_3{^-}$ concentrations followed by NF and AF. The trends for $PO_4^{-3}$ concentrations were similar in all fertilizer treatments when the fertilizer concentrations were equal. The above results indicate that neutral and basic fertilizers were most effective to promote 'Maehyang' strawberry growth when fertilizer solutions were controlled to low or high concentrations, respectively. These findings are useful for planning fertilization programs for vegetative propagation of 'Maehyang' strawberry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.677-683
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• 2010

This study investigated the effect of young Phragmites communis (Pc) leaves on lipid profiles, lipid metabolism and erythrocyte antioxidant defense system in high-fat diet fed mice. Three groups of mice were fed different diets for 8 weeks: normal diet (Normal), high-fat diet (High-fat; 37% calories from fat) and high-fat diet supplemented with 1% Pc (wt/wt, HF-Pc). Body weight, daily food intake and energy intake tended to decrease by Pc supplement in high-fat fed mice. Pc supplementation significantly lowered plasma triglyceride and total cholesterol concentrations compared to the high-fat control group. Pc also lowered hepatic and heart cholesterol contents, whereas it significantly increased fecal excretion of triglyceride and cholesterol compared to the high-fat control group. Pc significantly inhibited fatty acid synthase, 3-hydroxy-3-methylglutaryl CoA reductase and acyl-CoA:cholesterol acyltransferase activities compared to the high-fat control group. Erythrocyte superoxide dismutase and catalase activities were also significantly higher in the high-fat group than in the normal group, however Pc supplementation reversed these changes. The Pc supplementation significantly lowered erythrocyte lipid peroxidation level compared to the high-fat control group. Accordingly, these results suggest that Pc improves lipid metabolism and erythrocyte antioxidant defense system in high-fat diet fed mice.

• Annual Conference on Human and Language Technology
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• 1992.10a
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• pp.367-375
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• 1992

한국어는 다른 언어와는 달리 초성, 중성, 종성의 자소가 모여서 한 음절을 이룬다. 음절을 이루는 자소는 그 발생의 확률적 성질에 따라 확률변수로 간주된다. 음절 안에서 자소간의 발생의 상관관계는 자소간 조건부 확률 및 엔트로피로 표시된다. 음절이 모여서 단어를 이루고 단어를 이루는 음절은 그 발생의 확률적 성질에 따라 확률변수로 간주된다. 한국어 단어안에서 음절간의 발생의 상관관계는 음절간 조건부 확률 및 엔트로피로 표시된다. 수 있다. 그런데 가능한 음절의 종류가 매우 많기 때문에 음절 발생의 상관관계를 표시하는 지표로서 음절간 조건부 확률 대신 초성, 중성, 종성 단위의 조건부 확률을 사용하는 것이 음절간의 발생의 상관관계를 표시하는데 효과적이다. 이러한 한국어의 정보이론적 연구를 위하여서는 기초자료로서 한국어 단어의 빈도분포가 필요하다. 한국어 단어의 빈도분포의 포괄적인 조사는 1956년의 "우리말 말수 사용의 잦기 조사"가 유일한 실정이다. 시간 경과에 따른 한국어의 정보이론적 특성 변화의 분석을 위하여서는 한국어 단어 빈도의 주기적인 조사가 필요하다. 한국어에서 초성, 중성, 종성단위의 정보이론적 연구결과는 한국어 음성인식 및 함성, 자연언어처리, 암호법, 언어학, 음성학, 한국어부호 표준화 연구등에 이용될 것으로 기대된다. 남북한의 언어는 분단이 지속됨에 따라 상호 이질화가 진행되고 있다. 이러한 이질화를 극복하려는 부분적인 노력으로 남북한 언어의 한국어 영문표기의 단일화 등이 있었다. 이러한 노력에 병행하여 남한과 북한의 언어에 대한 정보이론적 비교 연구도 있어야 할 것이다. 정보를 효과적으로 캐싱할 수 있도록 인접한 데이터를 클러스터링해서 브로드캐스팅하여 이동 호스트의 구성 시간(setup time)을 최소화하였다. 그리고, 맨하탄거리(Manhattan Distance)를 사용해서 위치 의존 질의에서 사용하는 데이타를 캐싱하고 질의를 처리하는 방법을 제안한다. 맨하탄 거리를 이용해서 캐싱하면 도로에 인접해서 위치한 데이타를 효과적으로 캐싱할 수 있다. 또한, 거리 계산 방법으로 맨하탄 거리를 사용하면 도심에서 실제 이동 거리와 비슷한 값을 알 수 있고, 직선 거리 계산식에 비해서 계산식도 간단하기 때문에 시스템 계산량도 줄일 수 있다. 기준으로 라이신 부산물은 어분 단백질을 40%까지 대체가 가능하였으며, 아울러 높은 라이신 부산물의 대체 수준에 있어서 사료효율과 단백질 전환효율을 고려한다면 아미노산 첨가(라이신과 아르지닌)와 중화 효과에 좋은 결과가 있을 것으로 사료된다.의한 적정 양성수용밀도는 각고 5~6cm 크기의 경우 10~15개체가 적합하였다. 수증별 성장은 15~20 m 수층에서 빨랐으며, 성장촉진과 폐사를 줄이기 위해서는 고수온이 지속되는 7~10월에는 20~30m수층으로 채롱을 내려 양성하고 그 외 시기에는 15 m층 내외가 좋은 것으로 나타났다. 상품으로 출하 가능한 크기 인 각고 10 cm이상, 전중량 140 g 내외로 성장시 키기까지는 채묘후 22개월이 소요되었고, 출하시기는 전중량 증가가 최대에 이르는 3월에서 4월 중순이 경제적일 것으로 판단된다.er 90 % of good relative dynamic modulus of elasticity due

• 한국전기화학회:학술대회논문집
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• 1998.10a
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• pp.15-15
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• 1998

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1977.10a
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• pp.195.4-196
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• 1977

Trypsin에 대해서 비해물질을 생성하는 Streptomyces속 균주 AS 707을 선별하고 이 균주가 생성하는 물질의 작용성 및 제성질을 조사한 결과 본 저해물질은 열에 대해서 비교적 강하고 pH 처리에 대해서는 산성에서 중성에 걸쳐서는 안정하나 alkali성에서는 불안정했고 $\alpha-chymotrypsin과$ papain에 대해서도 저해작용을 하였으며 trypsin에 대한 저해양상은 mixed type이었다.(중략)