• Polymer(Korea)
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• v.29 no.2
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• pp.172-176
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• 2005

Environmentally friendly water dispersion polyurethanes containing fluorine were prepared with a fluorinated polyol having $62\%$ of fluorine $(Fluorolink^{(R)}\;M_n\;1000)$. In order to control the fluorine contents of the synthesized polyurethanes polytetramethylene glycol (PTMG2000) and $Fluorolink^{(R)}$ were mixed at assigned ratios and reacted with isophorone diisocyanate (IPDI) as a diisocyanate used. Introducing hydrophilic anion to the polymer chain was achieved by applying dimethyl propionic acid (DMPA). The ionic groups were neutralized with triethyl amine (TEA) before dispersion into water. Chain extension was executed by adding ethylene diamine at the final stage. Mechanical properties of the polymers showed that modulus increased with increasing $Fluorolink^{(R)}$ content. Surface energy values obtained from contact angle measurement decreased with increasing $Fluorolink^{(R)}$ content up to $20\%$. We expect that the synthesized polyurethanes present reliable effect from the fluorine atoms incorporated even at a small amount of $Fluorolink^{(R)}$.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.199-199
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• 1994

Thioglycerol과 glycerol로부터 rac-1-S-octa-decyl-2-O-palmitoyl-1-S-thioglycerol-3-phosphate (DL -PTBA-P)와 rac-1-O-octadecyl-2-O-palmitoyl-g1ycerol-3-phosphate (DL-PBA-P)등을 합성하였고, 이들에 ara-C 유도체인 ara-CMP morpholidate를 반응시켜 최종 산물인 ara-CDP-DL-PCA, ara-CDP-DL-PBA, ara-CDP-DL-PTCA 및 ara-CDP-DL-PTBA등을 합성하였다. 이들 최종산믈의 항암효과는 L1210 lymphoid leukemia, colon 26 carcioma, M5076 sarcoma, C-1300 neuroblastoma, 3-Lewis lung carcinoma, WEHI-3B leukemia, human colon cancer, hum an pancreatic cancer 등의 암세포주를 사용하여 실험하였다. L1210를 DB/2J의 뇌막 또는 복강, DBA/1J의 복강내에 이식하여 ara-C, Ehss thioether lipid의 ara-C 유도체 (ara-CDP-L-DP, ara-CDP-DL-PCA, ara-CDP-DL-PBA, ara -CDP-DL-PTCA, ara-CDP-D-PTBA, ara-CDP-L-PTBA, ara-CDP-DL-PTBA)를 단일 투여 또는 중복 투여하였고, 3-Lewis는 C57BL/6 의 발바닥 피하, colon26은 BALB/C의 견갑상부 히아조직, M5076은 C57BL/6의 피하, WEHI-3B는 BALB/C의 복강, C-1300는 A/strong Ros에 각각 이식한 후 ara-C 또는 ara-CDP-DL-PTBA를 단일 또는 중복 투여하였다.

• Journal of Korean Society of Steel Construction
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• v.22 no.6
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• pp.533-541
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• 2010

H-shaped beams, which are constructed between columns, are used widely as slaves in steel structures. The bending moments that occur on both ends of an H-shaped beam, however, are about twice the bending moment that occurs at the center of the H-shaped beam. Because such beam is designed with maximum bending moment, it is deeper and has smaller spaces. To improve these features, if both ends of an H-shaped beam that have maximum bending moments are merely reinforced, the beams could be designed by the bending moment at the center of the H-shaped beam. To analyze the structural performance of the proposed end-reinforced beams (eco-girders). Four specimens were prepared with the following parameters: end-reinforced steel plate, reinforced bars, and reinforced studs and experimental tests of the specimens were performed.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.3
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• pp.21-30
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• 2020

With the widespread of smartphones, the Quick response (QR) code became one of the most popular codes. In this paper, a new type of QR code is proposed to increase the storage capacities and also to contain private information by changing the colors and the shape of patterns in the codes. Then, for a variety of applications of the printed QR codes, this paper proposes an efficient authentic certification system, which is built on an conventional CNN (Convolutional neural network) architecture - VGGNet and classifies authentic or counterfeit with smartphones, easily. For authentic codes, the proposed system extracts the embedded private information. Through practical experiments with a printed QR code, it is shown that the proposed system can classify authentic or counterfeit code, perfectly, and also, are useful for extracting private information.

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.173-178
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• 2017

This study was conducted to investigate the effect of pyroligneous acids on urea hydrolysis for the purpose of inhibiting ammonia volatilization during urea fertilizer application. Different types of synthetic urease inhibitors have been searched and developed, but their use is limited due to varying inhibition effects on soil urease, and environmental problems. In this study, the effect of pyroligneous acids, a natural substance, on urea hydrolysis in soil was evaluated by analyzing inhibition of urease activity. Pyroligneous acids inhibited plant urease and microbial urease activity, as well as soil urease with various urease complex. In addition, pyroligneous acids exhibited non-competitive urease inhibition effect through urease kinetics and inhibited urea hydrolysis in the soil. This study showed that pyroligneous acids treatment with urea fertilizer decreases the loss of urea fertilizer, improves the efficiency of nitrogen application on plant and reduces the amount of nitrogen fertilizers applied in soil.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.68-71
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• 2001

Of the cyclic imide type compounds, S-275 was known to exhibit a potent herbicidal effects. We have designed and synthesized the compounds having diverse subsutuents in place of the chlorine group of bicyclic 4,5,6,7-tetrahydroindazole part of S-275. Their herbicidal activities were studied under flooded paddy conditions. The results showed that the most compounds gave relatively weak herbicidal activities, whereas tile compound substituted with methylthio group showed potent herbicidal effects against paddy weeds at a rate of 0.015 kg/ha and improved tolerance on rice compared to S-275.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.295-301
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• 2008

Phenylformamidines are well known as insecticides for their specific activity against the insects. It has now been established that they show insecticidal activity as agonists on the octopamine receptor which is located in the synapse membrane. In this study we tried to test the effect of fluorine substituted aromatic formamidines and 1,3,5-triazapenta-1,4-dienes. Among the compounds, 2h, 2k, 21, 3g, 3h, 3k showed good activity against mite and aphid and 4f and 4g showed high activity against mite.

• Journal of the Korea Society for Simulation
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• v.21 no.4
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• pp.81-90
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• 2012

Presented in this paper is a study for construction of a simulation system for the engagement of ground weapon systems. This paper proposes architecture for the simulation system based on agent simulation design methodology. Every entity of the proposed architecture is developed by assembling modularized agent components, and it enhances the reusability and composability of the entity. Consequently, time, costs, and efforts that are required to develop a new simulation system is able to be reduced by the enhancement. In the case of ground engagement simulation, it is very important to reflect environmental effects. Synthetic battlefield of the proposed architecture has environmental data of the battlefield and interacts with entities in the simulation system. The proposed architecture based simulation system can build swiftly various simulation models by the objectives and derive reasonable results from behaviors of entities that include environmental effects. This paper contains the construction of an example system based on the proposed architecture to verify the advantages of the architecture.

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.95-100
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• 2018

The metal oxide/graphene nanocomposites are promising functional materials for high capacitive electrode material of secondary batteries, and high sensitive material of high performance gas sensors. In this study, vanadium dioxide($VO_2$) nanostructrures were grown on CVD graphene which was synthesized on Cu foil by thermal CVD, and exfoliated graphene which was exfoliated from highly oriented pyrolytic graphite(HOPG) using a vapor transport method. As results, $VO_2$ nanostructures on CVD graphene were grown preferential growth on abundant functional groups of graphene grain boundaries. The functional groups are served to nucleation site of $VO_2$ nanostructures. On the other hand, 2D & 3D $VO_2$ nanostructures were grown on exfoliated graphene due to uniformly distributed functional groups on exfoliated graphene surface. The characteristics of morphology controlled growth of $VO_2$/graphene nanocomposites would be applied to fabrication process for high capacitive electrode materials of secondary batteries, and high sensitive materials of gas sensors.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.139-144
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• 1981

Modified radish Kimchi and radish-root juice were fermented under $N_2$ atmosphere at $22{\sim}23^{\circ}C$ and $37^{\circ}C$, respectively and their changes of vitamin C content. were determined by dinitrophenylhydrazine and indophenol methods. In the earlier period of the fermentation, vitamin C content decreased temperarily and then began to increase. When the flavor of Kimchi was most acceptable, vitamin C showed the maximum value which eras equivalent to or more than the initial, after which vitamin C content decreased gradually. The increase of vitamin C content seemed to come from the biosynthesis of the vitamin owing to the enzymatic action occurred in radish-root. The addition of galacturonic acid to Kimchi and to radish-root juice elevated the vitamin C content, which suggested galacturonic acid was a good substrate for the synthesis of vitamin C. The optimum pH of the Kimchi fermentation for the better vitamin C content ranged 4.0 to 4.5.