• The Korean Journal of Mycology
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• v.41 no.1
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• pp.42-46
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• 2013

Burkholderia pyrrocinia CAB08106-4 was parceled out from the Chungnam Agricultural Research and Extension Center, Korea to evaluate the antagonistic activity against garlic white rot caused by Sclerotium cepivorum. The optimum cultural conditions including temperature, pH, enzyme activity, carbon and nitrogen sources were determined. The optimum culture conditions of B. pyrrocinia CAB08106-4 were $286^{\circ}C$, 150 rpm and pH 7. Chitinase only showed activity among several tested enzymes. The highest cell growth was obtained with 1% glucose and 0.1% $(NH_4)_2SO_4$, respectively.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1076-1081
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• 2012

For the purpose of development of the latex suitable for latex modified concrete, experimental researches on the preparation of carboxylated styrene butadiene latex by the method of the two-step emulsion polymerization and application to concrete were performed. Sodium dodecylbenzene sulfonate and sodium salt of lauryl sulfonate were selected as anionic emulsifiers, and nonylphenoxy poly(ethyleneoxy) ethanols (n=10, 20, 40) as latex stabilizer. Potassium persulfate and sodium bisulfite were used as redox initiator, besides $Na_2HPO_4$ and $K_2CO_3$ as electrolytes. Polymerization recipe of latex suitable for latex modified concrete were suggested from the experimental researches on the effects of anionic emulsifiers and their concentration on the polymerization stability, and the effect of electrolytes concentration on the particle size of latex. Physical properties, such as slump, air contents, compressive and flexural strength, of latex prepared by suggested polymerization recipe were examined. The experimental results showed that latex modified concrete satisfied the quality standards in slump and air contents. Furthermore, it was turned out that the compressive and the flexural strength of latex modified concrete with 28 days curing time showed appreciably improvements.

• The Korean Journal of Applied Statistics
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• v.27 no.5
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• pp.755-771
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• 2014

Isotropy is one of the main assumptions for the ease of spatial prediction (named kriging) based on some covariance models. A lack of isotropy (or anisotropy) in a spatial process necessitates that some additional parameters (angle and ratio) for anisotropic covariance model be obtained in order to produce a more reliable prediction. In this paper, we propose a new class of geometrically extended anisotropic covariance models expressed as a weighted average of some geometrically anisotropic models. The maximum likelihood estimation method is taken into account to estimate the parameters of our interest. We evaluate the performances of our proposal and compare it with an isotropic covariance model and a geometrically anisotropic model in simulation studies. We also employ extended geometric anisotropy to the analysis of real data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.3
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• pp.277-287
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• 2003

As primary source data toward the systematic and efficient management of national land, the aerial photographs have been utilized in many different areas. However, the quality of aerial photographs does not meet the requirement of the users due to unidentified miscellaneous reasons. Aiming for the improvement of the quality of aerial photographs, we first investigated the current status of domestic rules and working procedures related to aerial photographing and film processing in great details. In addition, we investigated and analyzed those of advanced nations such as U.S.A., Canada, G.B. and so on. It was drawn from the comparison and analysis that the poor quality of domestic aerial photographs resulted from lack of the quantitative and objective standards on aerial photography specification as well as poor condition and aging problem of equipments such as aerial camera and film developing equipment. In this paper, we proposed a stepwise strategic plan which consists of the aerial photography specification and quantitative quality control standard taking into consideration the current status of domestic rules and working procedures.

• Journal of Applied Biological Chemistry
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• v.54 no.3
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• pp.218-224
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• 2011

This study was conducted to estimate the water quality of agricultural groundwater well located in Buan-gun, Jinan-gun, Sunchang-gun, and Jangsu-gun of Jeollabuk-do. The groundwater samples were collected at 328 sites (Buan-gun: 158, Jansu-gun: 45, Sunchang-gun: 32, Jinan-gun: 93, respectively). We measured 4 kinds of general contaminants (pH, $NO_3-N$, $Cl^-$, and COD) and 10 kinds of specific contaminants (Cd, As, $CN^-$, Hg, phenol, Pb, $Cr^{+6}$, organophosphorus, trichloroethylene, and tetrachloroethylene). Generally, the level of general contaminants and specific contaminants in the agricultural groundwater was suitable for water quality standard in all sites for agricultural irrigation water. Exceptionally, chloride concentrations were exceeded water quality standard of agricultural groundwater at some sites in western coast area of Jeollabuk-do. Although water quality standards in agricultural groundwater have been suitable, the water contaminants of agricultural groundwater in western coast area were gradually increased than eastern mountain area.

• Fire Science and Engineering
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• v.30 no.5
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• pp.100-107
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• 2016

Today, high-rise buildings expected to meet various needs and improve the quality of frequency of fire and the potential risks are increasing. In particular, the fire spread risk in the vertical direction is increasing. As a result there is a problem with delays in the evacuation time of occupants. To overcome this problem, there is a need to consider the structure of the building and develop a system for the early detection of fire by applying a fire alarm system according to the risk ranking. Therefore, this paper describes the vertical fire spread characteristics of a multistory double-skin and stairs structure with risk. The data were compared with that from the national and international fire alarms as well as with. smoke density, smoke detectors, visibility, and CO concentration using FDS. A fire alarm system for each structure is proposed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.10
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• pp.2054-2061
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• 2015

Biologically inspired modeling techniques have received considerable attention for their robustness, scalability, and adaptability with simple local interactions and limited information. Among these modeling techniques, Gene Regulatory Networks (GRNs) play a central role in understanding natural evolution and the development of biological organisms from cells. In this paper, we apply GRN principles to the WSN system and propose a new GRN model for decentralized node scheduling design to achieve energy balancing while meeting delay requirements. Through this scheme, each sensor node schedules its state autonomously in response to gene expression and protein concentration, which are controlled by the proposed GRN-inspired node scheduling model. Simulation results indicate that the proposed scheme achieves superior performance with energy balancing as well as desirable delay compared with other well-known schemes.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.15-30
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• 2002

최근 화장품 사용인구의 증가와 안전성에 대한 관심 증대에 따라 화장품 중 유해성분 함유에 대한 논란이 종종 있어왔다. 화장품에 대한 전문적 지식이 없는 사람들에 의하여 진행된 잘못된 정보로 인하여 화장품 중에 포함된 모든 중금속이 인체에 심각한 영향을 초래한다는 등의 오해를 불러와 관련 업계에 적지 않은 피해를 주기도 하였다. 이에 본 자료에서는 구체적 근거자료와 연구 논문들을 기반으로 유해한 중금속, 안전하여 사용이 공인된 중금속 등을 조사하여 화장품에서의 중금속의 개념을 정립하고자 하였다. 국내에서는 식품의약품안전청 고시 제2000-27호에 화장품에 포함되었을 때 유해한 중금속으로 납, 비소 및 수은을 명시하고 그 규제농도를 규정하고 있다. 규제 중금속은 아니지만 피부에 알러지를 일으키는 중금속으로는 니켈이 있는데 화장품 중 몇몇 제품군에서 소량(수∼수십ppm) 이 검출되기도 한다. 그러나 이는 일상으로 사용하는 각종 귀금속, 시계, 안경테, 클립, 지퍼 등의 금속 용품에 포함된 니켈의 양(수∼수십%)에 비하여 매우 적은 양이며 정상적인 사람에게는 무해하다. 실제 대다수의 니켈 알러지는 화장품이 아닌 귀금속이나 시계 등의 금속류 제품 등에 의하여 유발된다. 또한 많은 종류의 중금속 화합물이 화장품 원료로 사용되고 있다. 전세계적으로 널리 사용되는 것으로 크롬, 망간, 비스머스, 구리, 철, 코발트, 티타늄, 아연 등의 화합물이 있으며 이들은 각종 화장품 공정서 및 원료집 등에 수재되어 사용되고 있다. 이들 중 코발트와 크롬이 피부에 유해하다는 몇몇 보고가 있지만, 이는 이들 원소의 수용성염형태의 특정 화합물인 cobalt chloride와 chromate 및 dichromate의 염에 관한 것으로 화장품에서 사용되는 불용성 산화물인 cobalt aluminum oxide, cobalt titanium oxide, cobalt blue, chromium oxde greens 및 chromium hydroide green 등, 국제적으로 널리 사용되는 안전한 중금속 화합물과는 그 특성 및 독성이 판이하게 다르다. 따라서 화장품에서는 매우 안전한 중금속 화합물만이 사용된다. 업계는 유해 중금속에 관해서는 규제에 입각한 엄격한 품질관리에 힘쓰고 중금속의 화학적 분자구조(수용성염 vs 불용성산화물)를 구별할 수 있는 분석방법 개발에 주력하여야 한다. 그리고 안전한 화장품을 사용하고자 하는 소비자의 욕구를 충족시키고 잘못된 인식과 보도로 인하여 안전한 화장품이 유해한 것으로 오도되는 것을 막아야 할 것이다.

• Journal of the Korea Convergence Society
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• v.10 no.4
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• pp.131-138
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• 2019

Diesel engines have important advantages over its gasoline counterpart including high thermal efficiency, high fuel economy and low emissions of CO, HC and $CO_2$. However, NOx reducing is more difficult on diesel engines because of the high $O_2$ concentration in the exhaust, marking general three way catalytic converter ineffective. Two method available technologies for continuous NOx reduction onboard diesel engines are Urea-SCR and LNT. The implementation of the Urea-SCR systems in design engines have made it possible for 2.5l and over engines to meet the tightened NOx emission standard of Euro-6. In this study, we investigate the characteristics of NOx reduction with respect to engine speed, load, types of catalyst and the $NH_3$/NOx ratio and present the conditions which maximize NOx reduction. Also we provide detailed experimental data on Urea-SCR which can be used for the preparation for standards beyond Euro-6.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.237-242
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• 2022

In this study, a drying method that can effectively remove residual solvent from (+)-dihydromyricetin was developed. Residual acetone concentration was efficiently removed below ICH-specified value (5,000 ppm) by simple rotary evaporation with ethanol pretreatment. In addition, the residual ethanol met the ICH-specified value (5,000 ppm) by simple rotary evaporation through the addition of water, and the residual moisture also met the specified value (<4%) for active pharmaceutical ingredients. At all the drying temperature (35, 45, and 55 ℃), a large amount of the residual solvent was initially removed during the drying, and the drying efficiency increased when increasing the drying temperature. Removal of residual solvent by ethanol pretreatment was shown to be related to high vapor pressure of acetone-ethanol mixture and hydrogen bonding between acetone and ethanol.