• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2000.11a
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• pp.306-310
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• 2000

본 논문에서는 안테나 구조해 따른 PCS 전화기에 의해 인체두부에 유기되는 SAR 값을 비교 분석하였고, SAR 값에 영향들 주는 요인을 분석하였다. 안테나의 종류, 안테나의 부착위치, 단말기의 구조에 따른 1 g 및 10 g 평균 첨두 SAR 값을 계산하였고, 인체 두부의 깊이에 따른 SAR 분포의 변화를 살펴보았다. 플립형 단말기에 부착된 안테나 중에서는 side mounted PIFA(Planar Inverted F Antenna)의 1 g 및 10 g 평균 첨두 SAR 값이 각각 0.686 W/kg과 0.353 W/kg으로 가장 낮았다. 폴더형 단말기에 부착된 모노폴 안테나에 의한 1 g 및 10 g 평균 첨두 SAR값은 플립형에 의한 SAR 값에 비해 약 30 % 가량 낮은 것으로 나타났다. 평균 첨두 SAR 값이 낮은 값을 보이는 두 구조인 side mounted PIFA와 폴더형 구조의 모노폴 안테나의 깊이에 따른 SAR 분포는 나머지 두 구조에 비해 비교적 완만한 경사를 보였다.

• Journal of the Korean Chemical Society
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• v.58 no.6
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• pp.517-523
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• 2014

The micellization of TTAB(tetradecyltrimethylammonium bromide) and the solubilization of 4-halogenated phenol isomers in aqueous solution of that surfactant in water have been studied by the UV-Vis spectrophotometric method. Those properties in aqueous solutions of NaCl and n-butanol have been also measured to determine the interactions between the micelle and 4-halogenated phenols and the solubilized sites of those molecules in the micelle. The results show that the values of ${\Delta}G^o_m$ and ${\Delta}G^o_s$ are all negative and the trends of those values depend on both the kinds and the concentrations of additives. Namely, by adding NaCl both ${\Delta}G^o_m$ and ${\Delta}G^o_s$ values are all decreasing, but by adding n-butanol the ${\Delta}G^o_m$ value decreases and the ${\Delta}G^o_s$ value increases.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.225-229
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• 2006

This study was conducted to screen herbicidal activity of Korean native plants which could be used for the development of new natural herbicides. Fifty-five plants were collected from Wan and Jeju islands in Korea and their methanol extracts were obtained. Herbicidal activity of methanol extracts were determined by seed bioassay using rape (Brassica napus L.) seedlings. Among fifty-five species, five plants were highly herbicidal ($GR_{50}$ < 1,000 ${\mu}g\;g^{-1}$): Clematis apiifolia A. P. DC.; (811 ${\mu}g\;g^{-1}$), Euscaphis japonica (THUNB.) KANITZ (867 ${\mu}g\;g^{-1}$), Hibiscus mutabilis L. (988 ${\mu}g\;g^{-1}$), Phyllostachys pubescens MAZEL (778 ${\mu}g\;g^{-1}$), Yucca recurvifolia (857 ${\mu}g\;g^{-1}$). Twenty-seven plants were shown moderately herbicidal (1,000 < $GR_{50}$ < 2,000 ${\mu}g\;g^{-1}$), however, twenty-three plants were not shown any herbicidal activity.

• Journal of Plant Biotechnology
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• v.31 no.2
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• pp.163-167
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• 2004

The effects of sucrose concentration on the secretion of hGM-CSF, total protein and protease into the medium were investigated in transgenic tobacco cells. The dry cell weight (11.22 g/L), hGM-CSF (181.53 $\mu\textrm{g}$/L) and total protein (66.8 mg/L) were detected as highest at 30 g/L sucrose and protease activity (2660 U/L) was highest at 120 g/L sucrose after 5-day culture. However after 10-day culture, the maximum dry cell weight (28.36 g/L) was found at 60 g/L sucrose while the maximum hGM-CSF (95 $\mu\textrm{g}$/L) was appeared at 150 g/L sucrose. The total protein and protease activity was secreted as 52.28mg/L and 3430 U/L, respectively in the same culture.

• Childhood Kidney Diseases
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• v.11 no.1
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• pp.16-23
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• 2007

Purpose : Hypogammaglobulinemia has been observed in nephrotic syndrome, but its pathophysiology remains unknown. We evaluated the relationship between the serum IgG and at bumin levels for children with minimal change nephrotic syndrome(MCNS). Methods : The levels of immunoglobulin G(IgG), albumin and total cholesterol of a total of 46 children with MCNS(proteinuria $>40mg/m^2/h$, and serum albumin level <2.5g/dL were analyzed. Results : The mean values of albumin, IgG and total cholesterol in MCNS children were $1.7{\pm}0.3g/dL,\;368{\pm}143mg/dL\;and\;431{\pm}78mg/dL$, respectively. There was an inverse correlation between the albumin values and the total cholesterol values(r=0.68, P=0.0001), whereas there was a direct-proportional correlation between albumin values and the IgG values(r=0.4, P=0.01). Conclusion : The IgG level is associated with albumin level, and it may reflect the severity of urinary protein loss in MCNS. Further studies are needed to evaluate this phenomenon.

• The Korean Journal of Food And Nutrition
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• v.24 no.2
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• pp.159-165
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• 2011

This study was carried out to investigate the quality characteristics of pear jam containing fresh ginger(G1) and ginger powders; dried ginger powder(G2), freeze-dried ginger powder(G3), and hot-air dried ginger powder(G4). The moisture, crude protein, and crude ash content of the control group were significantly higher than those of the experimental groups (p<0.001, p<0.05, p<0.01). The pH of the dried ginger powder added jam(G2) was the lowest(p<0.05). Texture profile analysis found that the dried ginger powder added jam(G2) had the highest firmness, consistency, cohesiveness, and resistance to flow/viscosity among all samples(p<0.001). Regarding the spread-meter value of the pear jam, the control group (G1) and hot air-dried ginger powder added jam(G4) had the highest values. The dried ginger power added jam(G2) had the lowest value among the samples(p<0.01). Regarding the color values of the pear jam, the control group(G1) had the highest L and b values. Hot-air dried ginger powder added jam(G4), on the other hand, had the lowest(p<0.001). The opposite was true for a value: hot-air dried ginger powder added jam(G4) had the highest. From the sensory evaluation, a positive trend was observed for the appearance of the dried ginger powder added jam(G2)(p<0.001). For sweetness, the dried ginger powder added jam(G2) had the highest value. A positive trend was observed for the overall acceptability of the dried ginger powder-added jam(G2)(p<0.001). Therefore, the dried ginger powder-added sample(G2) seemed to be the most appropriate to make pear jam with high acceptability.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.152-159
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• 2008

The purpose of this study was to determine the accurate quantification of vitamin A in infant formula by comparing two different standard stock solutions as well as various sample weights using high performance liquid chromatography. The sources of uncertainty in measurement, such as sample weight, final smaple vloume, and the instrumental results, were identified and used as parameters to determine the combined standard uncertainty based on GUM(guide to the expression of uncertainty in measurement) and the Draft EURACHEM/CITAC Guide. The uncertainty components in measuring were identified as standard weight, purity, molecular weight, dilution of the standard solution, calibration curve, recovery, reproducibility, sample weight, and final sample volume. Each uncertainty component was evaluated for type A and type B and included to calculate the combined uncertainty. The analytical results and combined standard uncertainties of vitamin A according to the two different methods of stock solution preparation were 627 ${\pm}$ 33 ${\mu}$g R.E./100 g for 1,000 mg/L of stock solution, and 627 ${\pm}$ 49 ${\mu}$g R.E./100 g for 100 mg/L of stock solution. The analytical results and combined standard uncertainties of vitamin A according to the various sample weighs were 622 ${\pm}$ 48 ${\mu}$g R.E./100 g, 627 ${\pm}$ 33 ${\mu}$g R.E./100 g, and 491 ${\pm}$ 23 ${\mu}$g R.E./100 g for 1 g, 2 g, and 5 g of sampling, respectively. These data indicate that the preparation method of standard stock solution and the smaple amount were main sources of uncertainty in the analysis results for vitamin A. Preparing 1,000 mg/L of stock solution for standard material sampling rather than 100 mg, and sampling not more than 2 g of infant formula, would be effective for reducing differences in the results as well as uncertainty.

• The Journal of the Petrological Society of Korea
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• v.25 no.2
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• pp.151-163
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• 2016

The characteristics of the rock cleavage in Jurassic granite from Geochang were analysed. The evaluation for the three directions of rock cleavages was performed using the parameters such as (1) frequency of microcrack spacing(N), (2) total spacing(${\leq}1mm$), (3) mean spacing($S_{mean}$), (4) difference value($S_{mean}-S_{median}$) between mean spacing($S_{mean}$) and median spacing($S_{median}$), (5) density of spacing(${\rho}$), (6) difference value between two exponents for the whole range of the diagrams(${\lambda}_H-{\lambda}_L$), (7) mean value of exponent(${\lambda}_M$), (8) mean value of exponential constant($a_M$), (9) difference value between two exponents for the section under the initial points of intersection(${\lambda}t_H-{\lambda}t_L$), (10) mean value of exponent(${\lambda}t_M$) and (11) mean value of exponential constant($at_M$). The results of correlation analysis between the values of parameters for three rock cleavages and those for three planes are as follows. The values of (I) parameters(1, 2, 7 and 8) and (II) parameters(3, 4 and 5) are in orders of (I) H(hardway, (H1 + H2)/2) < G(grain, (G1 + G2)/2) < R(rift, (R1 + R2)/2) and (II) R < G < H. On the contrary, the values of the above two groups(I~II) of parameters for three planes show reverse orders. Besides, the values of parameter $6({\lambda}_H-{\lambda}_L)$, parameter $9({\lambda}t_H-{\lambda}t_L)$, parameter $10({\lambda}t_M)$ and parameter $11(at_M)$ for three planes are in orders of R(rift plane, (G1 + H2)/2) < H(hardway plane, (R2 + G2)/2) < G(grain plane, (R1 + H2)/2), H < G < R, H < R < G and R < H < G, respectively. The values of the above four parameters for three rock cleavages show the various orders of R < H < G, R < H < G, H < G < R and H < G < R, respectively. Meanwhile, the spacing values equivalent to the initial points of contact and intersection between the two directions of diagrams were derived. The above spacing values for three rock cleavages are in order of rift(R1 and R2) < grain(G1 and G2) < hardway(H1 and H2). The spacing values for three planes are in order of rift plane(G1 and H1) < hardway plane(R2 and G2) < grain plane(R1 and H2). In particular, the intersection angles for three rock cleavages and three planes are in order of rift and rift plane < hardway and hardway plane < grain and grain plane. Consequently, the two diagrams of rift(R1 and R2) and rift plane(G1 and H1) show higher frequency of the point of contact and intersection. These characteristics of change were derived through the general chart for three planes and three rock cleavages. Lastly, the correlation analysis through the values of parameters along with the distribution pattern is useful for discriminating three quarrying planes.

• Water for future
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• v.27 no.4
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• pp.49-57
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• 1994

This study was carried out to obtain Kinetic constant of Moving Media Complete Mixing Activated Sludge (MMCMAS) for the wastewater treatment. A laboratory MMCMAS reactor was operated at the organic loading rate of 2.5g$BOD_{5}$/$m^{2}$ /d~48g$BOD_{5}$/$m^{2}$/d kinetic constant of MMCMAS reactor was estimated as follows:

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.723-728
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• 2014

The physicochemical characteristics of coffees extracted using 7 different extraction methods were investigated. The pH values of coffees extracted via different extraction methods ranged from 5.26 to 5.54, and coffee extracted by Ibrik had the highest pH among all samples. The soluble solid content and titratable acidity of coffee extracted using an Espresso machine were significantly higher than those obtained using other extraction methods. Furthermore, the total phenol and caffeine contents of coffee extracted using an Espresso machine were 6.46 and 2.65 mg/mL, respectively. In regard to color, the $L^*$, $a^*$ and $b^*$ values of coffee extracted via different extraction methods were in the ranges of 0.81-38.94, 4.49-37.75, and 0.71-66.42, respectively. In regard to the phenolic compounds, the chlorogenic acid, caffeic acid and ferulic acid contents of coffee extracted using an Espresso machine were higher than those obtained by other extraction methods at 0.15 mg/mL, $0.075{\mu}g/{\mu}L$, and $0.019{\mu}g/{\mu}L$, respectively.