• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.9
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• pp.756-759
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• 2017

In this paper, the radar cross section of a tank is analyzed at millimeter wave W-band. We calculate the radar cross section of the tank using the program based on PO and PTD and the computed results are compared with those of commercial simulator to check the accuracy of computations. The radar cross section is calculated in terms of the incident angle, polarization, and tank with or without cannon. The radar cross section can be reduced by changing the shape of the turret that can be applied to stealth tanks.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.403-407
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• 2010

건축 구조재료로 사용되는 소나무의 화재조건을 알아보기 위하여 콘칼로리미터(ISO 5660-1)를 이용하여 연소성질을 분석하였다. 자연 건조된 소나무에 $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$ 등의 암모늄염을 이용하여 난연성을 부가하였다. 소나무의 함수율은 10.2%였으며 초기 열방출 곡선은 $(NH_4)_2HPO_4$인 경우 완만하게 증가하였으며 가장 좋은 난연성을 보였다. $HRR_{peak}$ 값은 무처리된 경우 $217\;kW/m^2$, $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$인 경우에는 각각 $190\;kW/m^2$, $188\;kW/m^2$, $166\;kW/m^2$로 나타났다. 즉 $(NH_4)_2HPO_4$로 처리된 경우 23.5%의 감소현상이 관찰되었다. $HRR_{peak}$ 도달 시간은 무처리된 시험편(290s) 및 $(NH_4)_2SO_4$, $NH_4H_2PO_4$, $(NH_4)_2HPO_4$으로 처리된 시험편은 각각 298s, 263s, 313s로 나타났다. 연기 발생속도는 사용한 암모늄염 중 $(NH_4)_2SO_4$로 처리된 시험편이 가장 작게 관찰되어 저발연성 감연제 역할을 하는 것으로 판단된다.

• Journal of Life Science
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• v.14 no.4
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• pp.560-566
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• 2004

Agrocybe aegerita is Hymenomycetes fungus belonging to the order Agaricales and family of Bolbitiaceae. Much less is known about liquid culture of Agrocybe aegerita. Thus, the present study was to investigate the liquid cultural characteristics of Agrocybe aegerita my-celium. The optimal medium for the mycelial growth and density was ME medium, optimal tem-perature and initial pH were 25$\pm$1$^{\circ}C$ and 5.5, respectively. And optimal culture time for mycelial growth was 12 days. The modified optimal medium compositions were dextrin 3% (w/v), yeast extract 2% (w/w), MgSO$_4$0.05% (w/v), and KH$_2$PO$_4$0.15% (w/v). Under optimal culture conditions, the mycelial growth of modified optimal medium was higher than that of ME medium.

• Journal of Life Science
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• v.13 no.4
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• pp.498-504
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• 2003

This Study was carried out to investigate the optimal mycelial growth of Pholiota nameko. The optimal medium for the mycelial growth was ME medium. The optimal temperature and pH were $25^{\circ}C$$\pm$1 and 5.5, respectively. The modified optimal medium compositions were glucose 3% (w/v), malt extract 0.25% (w/v), yeast extract 0.25% (w/v), $KH_2PO_4$ 0.046% (w/v), $K_2HPO_4$ 0.1% (w/v), $MgSO_4$ㆍ$7H_2O$ 0.05% (w/v). From the result of experiments on the optimal temperature, pH and nutritional requirements, the mycelial growth of modified optimal medium was higher than that of ME medium.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.135-139
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• 2016

We developed a liquid-liquid extraction method using an inorganic salt to dramatically improve the recovery efficiency of the anticancer agent paclitaxel from plant cell cultures. As a result of liquid-liquid extraction using a diverse types of inorganic salt (NaCl, KCl, $K_2HPO_4$, $NaH_2PO_4$, $NaH_2PO_4{\cdot}2H_2O$), NaCl gave the highest yield (~96%) and lowest partition coefficient (0.053) of paclitaxel. The optimal NaCl/solvent ratio, methylene chloride/MeOH ratio, and pure paclitaxel content for liquid-liquid extraction using NaCl were 1% (w/v), 26% (v/v), and 0.066% (w/v), respectively. Under the optimal conditions developed in the present method, most of the paclitaxel (~96%) was recovered from biomass by a single extraction step. In addition, this method facilitated 3-fold higher recovery efficiency of paclitaxel in a shorter extraction number than the conventional liquid-liquid extraction method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.1079-1082
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• 2015

In Article 23 of Technical regulations for Telecommunication Line and Facilities, we have criteria of separation distance between telecommunication lines and power lines, and its related exceptional conditions. However, this is a conflicts condition with Article 32 that provides the type of indoor telecommunication cables such as twisted-pair cables and optical fiber cables. Also, it is frequently raised that exceptional condition related the PoE cables with up to 15.4W is improved to accept PoE cables with up to 30W. In this paper, we have proposed improvement plans of Technical regulations for separation distance between telecommunication lines and power lines by analyzing the variety of standard specifications at home and abroad.

• Journal of Soil and Groundwater Environment
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• v.15 no.4
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• pp.39-45
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• 2010

In order to treat paddy soils contaminated by Pb, Cd, and As near the abandoned mine, $H_2PO_4$ was used for stabilization of Pb ($PO_4$/Pb mole ratio of 2/1). In addition, $CaCO_3$ and $FeSO_4$ were used as stabilizers for treating Cd and As (2% w/w), respectively. Leaching tests were conducted with artificial rain in the column to assess the heavy metal stabilization efficiency. The mass of heavy metals in the effluents passed through the columns were analyzed. The remaining heavy metals in the soils were also analyzed as Korean soil standard method, phytoavailability test and sequential extraction test. Lead in the effluent was not detected when $H_2PO_4$ was used as a stabilizer. This result suggests that $H_2PO_4$ is efficient for Pb stabilization. In addition results of sequential extraction scheme suggest that heavy metals are present as residual forms which is not easily extracted.

• Journal of Internet of Things and Convergence
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• v.10 no.6
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• pp.111-116
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• 2024

The core of blockchain technology lies in the fact that instead of a centralized approach, individual nodes autonomously create blocks, but go through a consensus process so that eventually, all nodes have the same blockchain ledger. The technology used in this process is the consensus algorithm. Additionally, the consensus algorithm also helps solve the issue of double spending. To address this, the consensus algorithms used, such as Proof of Work (PoW), Proof of Stake (PoS), and Delegated Proof of Stake (DPoS), have been examined. Therefore, this paper aims to examine the types of double-spending attacks in blockchain and propose a Delegated Proof of Stake (DPoS) consensus algorithm incorporating Counting Bloom Filters (CBF) to prevent double-spending attacks and collusion among delegates.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.901-905
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• 1995

Three flavonoid compounds, astragalin(1), isoquercitrin(2) and quercetin $3-O-{\beta}-D-xylopyranosyl(1-2)-{\beta}-D-glucopyranoside(3)$ isolated from the leaves of Eucommia ulmoides were identified and quantified by HPLC. All flavonoids were well separated on a ${\mu}-Bondapak\;C_{18}$ column with a mobile phase composed of THF-dioxane-MeOH-HOAc-5% $H_3PO_4-H_2O$(145 : 125 : 50 : 20 : 2 : 658). The contents of compound 1 in the methanol extract and n-butanol fraction were 0.09%(w/w) and 0.46%(w/w), of compound 2 were 0.08%(w/w) and 0.48%(w/w), and of compound 3 were 0.40%(w/w) and 1.22%(w/w), respectively.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.428-439
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• 2020

This study was carried out to investigate the effect of PO film on the increase of crop yield and energy saving through PO and PE film greenhouse application and comparison test. As a experimental greenhouse, two single span greenhouses (1-1 W) and two double span greenhouses (1-2 W) were used. During winter season, PO film (0.15 mm outer layer, 0.10mm inner layer) was used as a covering material of greenhouse in double layers for double-span (B15) and single-span(B21), and PE film used for double-span (B15), and single-span (B23) as a control. The experimental vegetable was tomato(Solanum lycopersicum L.) cultivated in soil and the cultivar of that was 'Happiness'. That was cultivated from December 3, 2019 to April 30, 2020. The temperature at night inside the greenhouse was maintained at 15℃, and the side and roof windows were opened to maintain 23 ~ 24℃ during the day. As a result, this study showed that the yield in single-span greenhouse(B21) covered with a PO film increased 20% and that in double-span greenhouse (B16) increased by 9% compared to the greenhouse covered with a PE film (B23, B15). Fuel consumption of the single-span greenhouse (B21) with the cover of PO film was reduced by 12.4% and that of double-span greenhouse was done by 11.5% compared to that of the PE film greenhouse (B23, B15) without any difference between them in growing state.