• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.575_576
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• 2009

최근 전력산업의 구조적인 측면에서는 수직적 형태의 분리 및 경쟁 도입, 그리고 민영화를 통한 효율 증진 등 전력산업 개편이 전세계적으로 이루어지고 있다. 전력산업의 개편 과정에서 전력공급자(ESP)는 불완전한 시장으로 인한 재정적인 위험에 직면한다. ESP가 재정적인 위험에서 근본적으로 벗어나기 위해서는 합리적인 전기 소매 가격의 책정이 필요하다. 본 논문에서는 현재 적용되고 있는 고정 소매 가격제에 대한 문제점을 제시하고 이를 극복하기 위해서 전기 공급 도매 가격의 변동성을 예측함으로써 헤징을 통한 새로운 요금제의 도입의 필요성을 제안하는 것이 본 논문의 목적이다. 본 논문에서 소개될 새로운 요금제인 Critical Peak Pricing(CPP)에서 전기 공급 도매 가격의 변동성의 예측은 CPP 요금을 적용하는데 중요한 역할을 담당하는 지표로 활용된다. CPP 요금을 적용함으로써 ESP의 재정적인 위험을 최소화하고 수요 탄력성이 반영되어 전기 소비자들과의 관계 향상 또한 유도될 수 있다.[4],[6]

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.341-346
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• 2011

To study the effects of salinity-sodicity on bacterial population and enzyme activities, soil samples were collected from the Bay of Yellow Sea, Incheon, South Korea. In the soils nearest to the coastline, pH, electrical conductivity ($EC_e$), sodium adsorption ratio (SAR), and exchangeable sodium percentage (ESP) were greater than the criteria of saline-sodic soil, and soils collected from sites 1.5-2 km away from the coastline were not substantially affected by the intrusion and spray of seawater. Halotolerant bacteria showed similar trends, whereas non-tolerant bacteria and enzymatic activities had opposite trends. Significant positive correlations were found between EC, exchangeable $Na^+$, and pH with SAR and ESP. In contrast, $EC_e$, SAR, ESP, and exchangeable $Na^+$ exhibited significant negative correlations with bacterial populations and enzyme activities. The results of this study indicate that the soil chemical variables related with salinity-sodicity are significantly related with the sampling distance from the coastline and are the key stress factors, which greatly affect microbial and biochemical properties.

• Journal of Korean society of Dental Hygiene
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• v.21 no.1
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• pp.41-51
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• 2021

Objectives: This study analyzes the demands of dental hygiene college students for English courses and proposes ways to improve English courses for college students majoring in dental hygiene that would take advantage of English for specific purposes (ESP) in the future. Methods: Using a structured questionnaire, four universities by region with departments of dental hygiene were selected at random, and out of a total of 260 college students majoring in dental hygiene, data of 258 students, excluding data with missing values, were considered for investigating the needs of English curriculum development using the SPSS program. Results: Total 82.1% of the students expected English programs, and they said that English was important, The proposal for English curriculum development indicated that although the number of English programs was sufficient, diversification of English programs or changes in methods of managing classes were required. As for the need for English programs (66.4%), they required more ESP, such as practical English for dental or dental terminology, which can be used clinically and more than English for general purposes (EGP). Conclusions: Students in dental hygiene showed a higher demand for more professional ESP that can use clinically as dental hygienists in the future. It is necessary to consider the reorganization of the curriculum or changes in the method of managing English classes by reflecting one demands of dental hygiene students.

• Parasites, Hosts and Diseases
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• v.51 no.4
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• pp.479-484
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• 2013

Neutrophils are the predominant inflammatory cells found in vaginal discharges of patients infected with Trichomonas vaginalis. In this study, we examined superoxide anion ($O^{\cdot}_{2^-}$) production by neutrophils activated by T. vaginalis. Human neutrophils produced superoxide anions when stimulated with either a lysate of T. vaginalis, its membrane component (MC), or excretory-secretory product (ESP). To assess the role of trichomonad protease in production of superoxide anions by neutrophils, T. vaginalis lysate, ESP, and MC were each pretreated with a protease inhibitor cocktail before incubation with neutrophils. Superoxide anion production was significantly decreased by this treatment. Trichomonad growth was inhibited by preincubation with supernatants of neutrophils incubated for 3 hr with T. vaginalis lysate. Furthermore, myeloperoxidase (MPO) production by neutrophils was stimulated by live trichomonads. These results indicate that the production of superoxide anions and MPO by neutrophils stimulated with T. vaginalis may be a part of defense mechanisms of neutrophils in trichomoniasis.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.04a
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• pp.137-137
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• 2019

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.317-323
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• 2018

BACKGROUND: This study was conducted to evaluate the water-dispersible clay content of paddy soils over the country in the summer rainy season as affected by cultivated years using heavy agro-machinery and soil properties such as texture and exchangeable sodium percentage. METHODS AND RESULTS: Water-dispersible clay content of 16 soil series of Korean paddy soils over the country were investigated in summer rainy season from July to August, 2006 by Middleton's method. Water-dispersible clay content ranged from non-detected to 4.8%, showing maximum value from the fine textured soils and high clay dispersibility in average from the coarse textured soils. Longer cultivated years using agro-machinery more than 40 hp result in higer water-dispersible clay content for 60% of studied paddy soils with less than 5% of exchangeable sodium percentage (ESP). Exceptionally, soils with relatively big difference of ESP at about 10 percent showed higher water-dispersible clay content with higher ESP. CONCLUSION: Long years of cultivation using agro-machinery with more than 40 hp enhanced water-dispersiblility of clay in approximately 60% of the studied paddy fields except for salt-affected soils.

• Journal of Korea Society of Industrial Information Systems
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• v.10 no.2
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• pp.67-75
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• 2005

In this paper, we design and implement real time IP security packet analyzer on IPv4 and IPv6 network. This packet analyzer sniffs and analyzes the packets generated by the protocols that are used by IPsec, IKE, IPv4 and IPv6 such as AH, ESP, ISAKMP, IP, ICMP and so on. The purpose of this analyzer is to check current security status of the network automatically. In this paper we provide implementation details and the examples of security evaluation by using our security packet analyzer system.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.92-99
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• 2000

To compare the effect of food waste compost(FWC) application on the sodicity of paddy and upland soil, laboratory experiment was conducted. Six kinds of FWC made of various mixing ratio of food waste and pig slurry as raw material were applied to paddy soil under submerged condition and to upland soil in field water capacity, and were kept at $25^{\circ}C$ under laboratory incubation. The higher the mixing ratio of food waste on making FWC, the higher the FWC showed Na content and EC. Mineralized ratio of cations in FWC during incubation showed no difference between paddy and upland soil. It was high in the order of Na>K>Mg>Ca as 99, 94, 71, and 71%, respectively. NaCl contents of FWC applied to soils against SAR and ESP were fitted well to first linear regression with extremely high significance($R^2=0.99$). Increasing rate of SAR and ESP was higher in upland soil than paddy soil by 2.3 times. The difference was considered to be caused by dilution effect which was exerted by the application of more soil to water ratio to paddy soil than to upland soil on SAR analysis in consideration of cultivating condition. The calculated values of $([Ca^{2+}+Mg^{2+}]/2)^{1/2}$ used as a denominator on SAR calculation showed a little difference among FWC treatments by 2.1~2.4, while [$Na^+$] used as a numerator showed much variance by 3.1~9.5. Therefore, as a parameter for the assessment of FWC quality affecting soil sodicity, the use of only Na content in FWC was proposed without regarding Ca and Mg contents. Soil Ex. Na contents showed extremely high correlation($R^2=0.99$) with ESP. Moreover, because the former can be more easily determined than the latter, soil Ex. Na content was proposed as a new sodicity index.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1893-1897
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• 2010

The total polyphenol contents and antioxidative activities of water and ethanol extracts from Synurus excelsus and Synurus palmatopinnatifidus var. palmatopinnatifidus were determined. Total polyphenol contents of ESE and ESP were 195.7 and 216.2 mg/g, and were higher than WSE (74.7 mg/g) and WSP (77.4 mg/g). The total flavonoid contents were also higher in ESE (176.6 mg/g) and ESP (148.8 mg/g) than WSE and WSP. DPPH radical scavenging activities of ESE and ESP (73.1 and 73.4%) were higher than WSE and WSP as like total polyphenol and flavonoid contents. Although the DPPH radical scavenging activities of the extracts were proportional to total polyphenol contents, there are no differences between water extracts and ethanol extracts of Synurus excelsus and Synurus palmatopinnatifidus on ABTS radical scavenging activities. Moreover, all the solvent extracts (ESE, ESP, WSE and WSP) had no SOD-like activity. These results suggest that consideration for adoption of method is necessary to evaluate antioxidative activity of extracts from plants including vegetables.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.4
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• pp.524-533
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• 2003

DBD(Dielectric Barrier Discharge) plasma in air is well established for the production of large quantities of ozone and is more recently being applied to aftertreatment processes for HAPs(Hazardous Air Pollutants). Aim of this work is to determine design and operating parameters of a hybrid air cleaning system. DBD and ESP(Electrostatic Precipitator) are used as nano particle charger and collector, respectively. Pelletized MnO$_2$ catalyst or activated carbon is used fer ozone decomposition or adsorption material. AC voltage of 7～10 KV(rms) and 60 Hz is used as DBD plasma source. DC - 8 KV is applied to the ESP for particle collection. The overall particle collection efficiency for the hybrid system is over 85 % under 0.64 m/s face velocity. Ozone decomposition efficiency with pelletized MnO$_2$ catalyst or activated carbon packed bed is over 90 % when the face velocity is under 0.4 m/s in dry air.