• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.157-164
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• 2021

Smart agriculture requires sensing systems which are fundamental for precision agriculture. Adequate and appropriate water and nutrient supply not only improves crop productivity but also benefit to environment. However, there is no available soil sensor to continuously monitor nutrient status in soil. Electrical conductivity (EC) of soil is affected by ion contents in soil and can be used to evaluate nutrient contents in soil. Comparison of various commercial EC sensors showed similar water content and EC values at water content less than 20%. Soil EC values measured by sensors decreased with decreasing soil water content and linearly correlated with soil water content. EC values measured by soil sensor were highly correlated with water soluble nutrient contents such as Ca, K, Mg and N in soil indicating that the soil EC sensor can be used for monitoring changes in plant available nutrients in soil.

• Environmental Engineering Research
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• v.23 no.4
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• pp.345-353
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• 2018

This paper summarizes results of research on the electrochemical (EC) degradation of disinfection by-products (DBPs) and iodine-containing contrast media (ICMs), with the focus on EC reductive dehalogenation. The efficiency of EC dehalogenation of DBPs increases with the number of halogen atoms in an individual DBP species. EC reductive cleavage of bromine from parent DBPs is faster than that of chlorine. EC data and quantum chemical modeling indicate that the EC reduction of iodine-containing DBPs (I-DBPs) is characterized by the formation of active iodine that reacts with the organic substrate. The occurrence of ICMs has attracted attention due to their association with the generation of I-DBPs. Indirect EC oxidation of ICMs using anodes that produce reactive oxygen species can result in a complete degradation of these compounds yet I-DBPs are formed in the process. Reductive EC deiodination of ICMs is rapid and its overall rate is diffusion-controlled yet I-DBPs are also produced in this reaction. Further progress in practically feasible EC methods to remove DBPs, ICMs and other trace-level organic contaminants requires the development of novel electrocatalytic materials, elimination of mass transfer limitations via innovative design of 3D electrodes and EC reactors, and further progress in the understanding of intrinsic mechanisms of EC reactions of DBPs and TrOC at EC interfaces.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.411-419
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• 2019

The purpose of this study was to analyze the growth and functional differences between C. rotundus and G. littoralis according to different electrical conductivity (EC) conditions in reclaimed soil conditions. C. rotundus and G. littoralis seeds were sown in a tray and managed for seedlings stage for eight weeks. They were transplanted in the pots containing reclaimed soils sampled in the Saemangum region. The plants were grown in the reclaimed land soil for 12 weeks under the control, 1, 2, 4, and $8dS{\cdot}m^{-1}$ conditions and in horticultural soils with EC $1.0dS{\cdot}m^{-1}$. Plant height, leaf length and width of C. rotundus were the highest in EC $1dS{\cdot}m^{-1}$. Leaf, flower and tuber numbers of C. rotundus were the highest in EC $2dS{\cdot}m^{-1}$ and the lowest in EC $8dS{\cdot}m^{-1}$, and SPAD was the highest in EC 2 and $4dS{\cdot}m^{-1}$ and the lowest in EC $8dS{\cdot}m^{-1}$. The fresh weights of shoot and root of C. rotundus grown under EC $2dS{\cdot}m^{-1}$ increased and then decreased as the concentration increased. When compared plant growth between reclaimed soil and horticulture soil with EC $1dS{\cdot}m^{-1}$, the fresh weights of shoot and root, SPAD, leaf number, flower number, and tuber number were higher in horticultural soils. Although G. littoralis grown under EC $8dS{\cdot}m^{-1}$ was the lowest in all growth parameters, there were no significant differences among other EC treatments. C. rotundus had the highest p-coumaric acid content in EC $1dS{\cdot}m^{-1}$. And the catechin content in shoot of G. littoralis was the highest in the control, and root of Glehnia littoralis had the highest benzoic acid contents in EC $1dS{\cdot}m^{-1}$. If the soil EC is well managed within $4.0dS{\cdot}m^{-1}$, two plants would be cultivated in reclaimed land.

• Korean Journal of Environmental Agriculture
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• v.38 no.2
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• pp.69-75
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• 2019

BACKGROUND: Measurement of electrical conductivity of saturated soil paste ($EC_e$) for assessment of soil salinity is time-consuming, and thus conversion of EC of 1:5 soil-water extract ($EC_{1:5}$) to $EC_e$ using a dilution factor may be of help to monitor salinity of huge number of soil samples. This study was conducted to evaluate the dilution factor for reclaimed tideland (RTL) soils of South Korea. METHODS AND RESULTS: Soil samples (n=40) were collected from four RTLs, and analyzed for $EC_{1:5}$, $EC_e$, and cation compositions of 1:5 soil-water extract. The dilution factor (8.70) was estimated by regression analysis between $EC_{1:5}$ and $EC_e$, and the obtained dilution factor was validated by applying to an independent data set (n=96) of $EC_{1:5}$ and $EC_e$. The $EC_e$ measured and predicted was strongly correlated ($r^2=0.74$, P<0.001), but $EC_e$ was overestimated by 16% particularly for the soils with high clay content and low sodium adsorption ratio (SAR). CONCLUSION: This study suggests that using the dilution factor to convert $EC_{1:5}$ to $EC_e$ is feasible method to monitor changes in the soil salinity of the study RTL. However, overestimation of $EC_e$ should be cautioned for the soils with high clay content and low SAR.

• Electronics and Telecommunications Trends
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• v.8 no.3
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• pp.142-162
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• 1993

EC 회원국들은 1992년 12월 31일을 기하여 시장통합을 실시하였다. 세계 각국에서의 EC의 시장통합에 대응하는 정책들을 펴나가고 있는 가운데, 특히 시장통합 프로그램 중 중요한 부분이라고 할 수 있는 정보통신표준화 분야에 있어서 효과적인 대응정책을 수립하기 위해, EC 정보통신표준의 종류, 표준화 추진체계 및 주요 기관들의 조직, 기능 등 표준화활동, 현황을 분석하여 봄으로써 EC 표준화제도를 이해하여 국내의 효율적인 표준화추진체계 정립은 물론 EC 통합에 대한 우리나라의 대응 전략수립에 도움을 주려한다.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.167-172
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• 2006

The objective of this study was to determine the effects of substrate water content and electrical conductivity (EC) on the incidence of brown fruit stem and blossom end rot in glasshouse sweet pepper (Capsicum annuum cv. Special). Three levels of water content and EC had been treated since the first fruit reached 3cm in diameter: that is, 49 (low), 65 (medium), and 86% (high) for water content, and 2.4 (low), 4.2 (medium) and $6.3dS{\cdot}m^{-1}$(high) for EC. Shoot growth was reduced with decreasing water content, and it was lower in both high and low EC treatments than medium EC treatment. Fruit weight at harvest was greater in both medium and hish water content treatments than low water content treatment (158g vs 146g). High EC reduced fruit weight compared to or low EC treatments. The incidence of brown fruit stem increased with increasing water content and with decreasing EC. The highest incidence was shown in the high water content/low EC treatment (38%), which was considerably higher than 2.4% of the low water content/high EC treatment. Blossom end rot occurred in general in the low water content and/or high EC conditions. These results indicated that substrate water content and EC should be controlled differently according to the growth stage, to reduce the incidence of blossom end rot and brown fruit stem in glasshouse sweet pepper. First, to reduce blossom end rot incidence, water content should be maintained high (86%) and EC low ($2.4dS{\cdot}m^{-1}$) until Sweets after fruit set. Secondly, to reduce brown fruit stem incidence, water content should be maintained low (49%) and EC high ($6.3dS{\cdot}m^{-1}$), especially after completion of fruit growth.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.25
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• pp.123-163
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• 2005

The strategic alignment between internet marketing's strategic orientation and EC system's strategic orientation is an important concept in Electronic Commerce. This study measured internet marketing's strategic orientation, EC system's strategic orientation, strategic alignment, and strategic EC performance based on previous studies. Analysis of data gathered in mail survey of korea firms in KOSPI and KOSDAQ. The findings suggest that companies with high strategic alignment are better performing EC strategically, and internet marketing and EC system's strategic orientation are positive related to strategic alignment and performance of EC. This study supports that the level of the EC executive's participation in internet marketing planning influences strategic alignment of the EC plan with the internet marketing plan. Further, high levels of that alignment are associated with increased use of EC for strategic performance.

• Proceedings of the Technology Innovation Conference
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• 1999.12a
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• pp.328-347
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• 1999

The substitution of Electronic Commerce(EC) for the traditional transactions triggers the changes of the industry structures and promotes the cost reductions of the firms in the areas of distributions and other administrative operations associated with purchase via EC. Our study clarifies the changes of the environments attributable to EC which are faced inter-and-externally by firms and try to exhibit the trend of EC market growth through such descriptions. Regardless of the rapid spread of EC, recent studies do not show appropriately its impact on the relevant industries and our domestic economy. Therefore, our study focuses on the forecasting of the impacts of EC on the domestic productions and imports. To this end, we develop an analytic framework using the existing data in Input/Output Analysis and the estimations of the EC market growth in the future. We, finally, identify the industrial sectors whose productions and imports are estimated to be accelerated by the extension of EC and forecast the whole effects of EC on domestic productions and imports.

• Proceedings of the Korea Database Society Conference
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• 2000.11a
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• pp.142-151
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• 2000

전자상거래 시장의 폭발적인 성장에도 불구하고 전자상거래 업체들은 날로 치열해 지는 글로벌 시장경쟁 하에서 성공적인 기업으로 성장 발전해 나가기 위해서는 효과적인 사업전략을 구사하고 기업 고유의 차별적 경쟁우위를 확보해야 할 필요성이 대두되고 있다. 이를 위해서는 기업 경쟁전략 및 업무 부문별 실천전략 수립과 구체적인 제품 및 서비스의 제공전략 등이 종합적인 차원에서 일관성 있게 수립되어야 한다. 본 논문은 이와 같은 연구의 필요성 인식 하에서 EC의 기본적인 사업전략 수립 프레임워크와 기능부문별 전략(특히 마케팅 전략)을 종합적으로 검토하는 것을 연구 목적으로 삼고자 한다. 이를 위하여 본 연구는 첫째, Porter의 본원적 전략에 취급상품의 범위 및 경쟁전략을 독립변수로 추가하여 EC 전략을 제시하고자 한다. 본 연구에서 제시하는 EC 전략의 횡축은 총체적 비용우위 전략, 차별화 전략을, 종축은 포터의 집중화 (Focus) 전략에 대한 구분의 형태이다. 둘째, EC의 마케팅전략은 기존의 4P전략에 근거하여 수익획득방식, 상품취급방식, 운영방식, 광고홍보방식으로 구분하여 제시한다. 궁극적으로 EC전략에 따른 EC 마케팅전략의 차이를 분석함으로써 종합적인 EC 전략의 수립이 가능할 것으로 판단된다.

• Journal of Information Technology Services
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• v.2 no.1
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• pp.75-83
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• 2003

Among EC areas. the B2B EC market is being spotlighted as an important interesting research area considering its size and the potential impact on companeies and the whole society. In comparison with private consumers in B2C EC. business buyers in B2B EC have to precisely keep track of the purchase records. and integrate them with the buyer's e-procurement system, which might have been implemented as a part of integrated ERP (Enterprise Resource Planning) systems. There are three approaches for such integration between ERP and e-marketplace in B2B EC; Two previous approaches are Inside-Out approach and Outside-In approach. And a newly, one is b-cart approach. In this paper, we try to survey these three approaches and make a comparison analysis. From this research. we identify that the b-cart approach is the most efficient framework in integrating ERP with e-marketplace in B2B EC.