• Korean Journal of Human Ecology
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• v.4 no.1
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• pp.79-92
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• 2001

E. coli transformants EC3, EC4. and EC6. harboring citron oil degrading pathway genes, were co-cultured in M9 media with citron oil as a sole carbon source at 28$^{\circ}C$. Each co-culture(EC3+EC4, EC3+EC6, EC4+EC6 and EC3+EC4+EC6) showed three to four times higher cell growth than each transformant single culture. Microbial conversion products from the co-cultures were determined by GC-MS. Linalool. 4-terpineol and ${\alpha}$-terpineol were the major common products from co-cultures. Various minor products also were detected and important in flavor characteristics of cultures.

• Korean Journal of Construction Engineering and Management
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• v.7 no.3 s.31
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• pp.65-75
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• 2006

Emerging trends regarding USFK(United States Forces, Korea)'s EC(Engineering/Construction) market include: (1) introduction of MATOC(Multiple Award Task Order Contract); (2) increase of DB(Design-Build) contract; and (3) encroachment of large US-origin private EC firms upon Korea. This study analyzes the change of USFK's EC market with focus on the change of construction management actors for USFK's EC projects. Specifically, USFK's EC projects have been managed by FED(Far East District). Recently, however, the large US private EC companies substitute the role previously taken by FED. This phenomenon is accelerated by the business chances in Korea due to LPP(Land Partnership Plan) and intentions of US Government to save military construction costs by means of utilizing US private EC companies. The large US EC firms entering into Korea are business opportunities as well as challenges to Korean EC firms, which are contracting USFK's EC projects. This study concludes that, through teaming joint venture with the large US EC firms, the market changes can be opportunities to acquire foreign market information and learn advanced construction management skill from them.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2005.11a
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• pp.357-360
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• 2005

Domestic enterprises are surveyed and analyzed to find the empirical relationship between environmental characteristics and electronic commerce(EC) performance. Dynamism, hostility and heterogeneity are selected as environmental characteristics. EC performance is articulated as EC utilization, EC satisfaction and EC usefulness. Empirical test presents that dynamism has a statistically significant relationship with EC performance except EC usefulness, but hostility and heterogeneity have no statistically significant relationship with EC performance. The impact of industry type on environmental characteristics and EC performance is also tested.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2003.11a
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• pp.109-131
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• 2003

This Study intends to find the impact of industry type on the relationship between Electronic Commerce(EC) implementation and performance. For this purpose, empirical study of domestic small and medium enterprises(SMEs) is carried out to test the relationship between EC implementation and EC performance and the moderating effect of industry type on the relationship between them. Previous empirical studies on EC mostly focused on the adoption of EC by business firms, and also have been carried out with the data from big enterprises. More often than not, the results obtained from the large business firms are used to provide the guidelines for SMEs. SMEs are, however, different from large business firms in many aspects, and need to be studied on their own. Empirical test shows that there are differences between manufacturing industry and service industry in utilizing EC and in achieving EC performance. The results of data analysis indicate that the industry type of SMEs is moderating the relationship between EC implementation variables(EC type, EC strategy, EC formality and EC character) and EC performance variables(EC utilization, EC satisfaction and EC usefulness).

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.543-548
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• 2000

EC-2B와 EC-2C 획분은 정향(Eugenia caryophyllata)의 알칼리 추출물로부터 에탄올 침전, cetavlon 처리 및 한외여과를 거쳐 분획하였다. EC-2B 획분은 APTT에서 항응고 활성을 가지는 반면, EC-2C 획분은 APTT와 TT 모두에서 항응고 활성을 가지고 있으며 EC-2B와 EC-2C에서 모두 혈소판 응집억제능을 관찰할 수 있었다. EC-2B와 EC-2C 획분의 경구투여에서 두 획분 모두 독성이 없었으며 EC-2B 획문은 1,000 mg/kg (mouse, intravenours)에서도 독성이 없었으나, EC-2C 획분은 LD50 322 mg/kg 정도의 독성을 가지고 있었다. 두 획분의 in vivo 성에서의 항응고 활성을 60% 생존율을 갖는 dose로 표시한 결과 EC-2B는 131 mg/kgdlsep 비해 EC-2C는 58 mg/kg로 활성의 차이가 in vitro에서 보다 크게 나타났다. 이 두획분을 sulfation시킨 후 활성의 변화를 ex vivo를 통해 확인한 결과 두 획분 모두 활성이 증가하였으며 특히 EC-2B 획분의 활성이 급격히 증가하였다.

• Journal of Information Technology Applications and Management
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• v.15 no.3
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• pp.127-152
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• 2008

This study sought to explore how SMEs are utilizing EC. Drawing on existing research on IT and EC related field, this study presented the framework of EC utilization level and analyzed its affecting factors in the point of organizational perspectives; strategy and competency. The impact of EC utilization on firm performance was also examined by employing BSC. Structural equation model was applied to test the relationships among the theoretical constructs with data from 171 SMEs. The results showed that the rate of EC utilization in SMEs is growing quite rapidly. However, manufacturing related firms still remain at a lower level compared to service related firms. As for the two affecting factors of EC utilization level, it was found that the level of EC utilization appeared to be driven not by strategy but by competency. This result implicates that EC utilization in SMEs doesn't reach to strategic purpose yet, while it is dependent on firm's competency. As far as the impact of EC utilization on firm performance, the study showed that the level of EC utilization has significant relationship with all perspectives performance indicators of BSC. This study can provide the managers with current EC utilization pattern and the guidelines as to where to put the efforts in the EC utilization and how to get an effective EC utilization strategy in the future.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.1
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• pp.1-7
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• 2003

Time domain reflectometry (TDR) is a newly developed method for measuring simultaneously solute concentrations and volumetric water content of soil. Bulk electrical conductivity ($EC_a$) of soil is obtained from TDR signal using several equations proposed, and electrical conductivity of soil solution ($EC_w$) can be calculated using the linear relationship $EC_a=EC_w\theta(a\theta+b)+EC_s$ between $EC_a$ and $EC_w$ at constant soil water content. The objectives of this study were to evaluate $EC_a$ proposed by several workers and to obtain the empirical constants (a, b, and $EC_s$) for $EC_w$ of the soils from A, Bl, and B2 horizon of an agricultural field (Coarse loamy, Fluvaquentic Eutrudepts). The $EC_a$ proposed by Yanuka et al. responded most sensitively to the KCl solute concentrations. The empirical constants of a, b, and $EC_s$ for $EC_w$ were -0.249, 1.358, and 0.054 for A horizon, -2.518, 2.708, and 0.097 for Bl horizon, and 2.490, -0.250, and 0.103 for B2 horizon, respectively. Therefore, the results of this study showed that Yanuka et al. equation was most useful one in determining $EC_a$, from TDR signal for agricultural soil with low salinity and that the empirical constants for the calculation of $EC_w$, from $EC_a$ can be obtained through a simple calibration experiment.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.27-27
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• 2022

(-)-Epicatechin (EC), a primary form of flavan-3ol and a building block of proanthocyanidins, has health benefits as it is a potent antioxidant. So far, no quantitative trait loci (QTLs) associated with EC have yet been identified in soybean. In this study, QTLs for EC and hilum color were identified in recombinant inbred lines (RILs) derived from the varieties Jinpung and IT109098 using high-resolution single nucleotide polymorphism linkage mapping. This revealed two major QTLs for EC content, qEC06 and qEC08. qEC06 spanned the T Locus encoding flavonoid 3'-hydroxylase. qEC08, located near the I locus on Chr08, was also a major QTL for hilum color; however, allelic stacking of qEC08 and I revealed no relationship between I and EC content. RILs with IT 109098 alleles at both qEC06 and qEC08 had higher EC content than other lines. These results will enable the production of soybean varieties with high EC content via marker-assisted selection.

• Horticultural Science & Technology
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• v.29 no.4
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• pp.311-316
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• 2011

This study aimed to determine the effect of EC (electrical conductivity) levels of nutrient solution in hydroponic culture on allyl-isothiocyanate (AITC) content within plant tissues, Vitamin C content and physiological responses in wasabi plant (Wasabia japonica M. 'Darma'). The 'Darma' was grown for 5 weeks with a deep flow technique (DFT) system controlled at 5 different EC levels, including 0.5, 1, 2, 3, and $5dS{\cdot}m^{-1}$. In result, the highest total content of AITC showed at EC level 5 and $3dS{\cdot}m^{-1}$ for 1 or 5- week, respectively. The total content of AITC increased about 1.2-1.4 times when the plants were grown in the EC levels between 0.5 and $2dS{\cdot}m^{-1}$, whereas the content decreased about 6 and 56 % in the EC level 3 and $5dS{\cdot}m^{-1}$, respectively. The content of AITC was relatively higher in petiole tissue, about 53 %, taken from 1 week-grown plants when the EC was controlled between 0.5 and $2dS{\cdot}m^{-1}$. Root tissue also had relatively higher content of AITC, about 45.1 %, when the EC was controlled at 3 and $5dS{\cdot}m^{-1}$. However, a 5-fold decrease in the AITC content was found in blade tissue and a 6.8-fold decrease in root when the EC was controlled at $5dS{\cdot}m^{-1}$ for 5 weeks. There was no significant difference in the vitamin C content in 1-week grown leaf tissues under the different EC level treatments; but, the content increased about 27% in 5-week grown plants at the EC level between 0.5 and $2dS{\cdot}m^{-1}$, compared to the 1 week-grown leaf tissue. Electrolyte leakage of leaf tissue taken from 3-week grown plant was 3-fold higher at the EC level $5dS{\cdot}m^{-1}$, compared to the EC level between 0.5 and $2dS{\cdot}m^{-1}$. Chlorophyll content, photosynthesis rate and transpiration rate were decreased when the EC was controlled at higher than $2dS{\cdot}m^{-1}$. Leaf water content, specific leaf area and growth were decreased when the EC was controlled at $5dS{\cdot}m^{-1}$ for 5 weeks. All the integrated results in this study suggest that the EC level of nutrient solution should be maintained at lower than $3dS{\cdot}m^{-1}$ in order to improve nutritional value and quantity required for hydroponically grown wasabi as functional vegetable.

• Journal of Practical Agriculture & Fisheries Research
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• v.24 no.4
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• pp.5-10
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• 2022

After ginseng seeds were planted in sand, the first experiment was conducted by germinating seeds with a nutrient concentration of 0 to 2.5. The average germination rate was highest in EC 1.0 with a nutrient concentration of 87%, followed by the comparative group with EC 1.5, 82%, EC 2.0, 78%, EC 2.5, 72%, EC 0.5, 71%, and con, 68%. Ginseng seeds were sown in the sandy soil, grown for 60 days were transferred to the ginseng soil, and the second growth experiment was conducted 30 days later. As a result of the experiment, at the nutrient concentration of EC 1.5, it grew from 11.64cm to 15.54cm, the average total length(cm)increased the most from 3.90cm. At the EC 1.0, nutrient concentration, the average total weight(g)increased the most from 0.42g to 0.75g to 0.33g. At the EC 0.5, nutrient concentration, the average total root width(mm) increased the most from 4.06mm to 5.52mm to 1.46mm.