• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.905-915
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• 1994

Let $M_g$ be the moduli space of isomorphism classes of genus g smooth curves. It is a quasi-projective variety of dimension 3g - 3, when $g > 2$. It is known that a complete subvariety of $M_g$ has dimension $< g-1 [D]$. In general it is not known whether this bound is rigid. For example, it is not known whether $M_4$ has a complete surface in it. But one knows that there is a complete curve through any given finite points [H]. Recently, an explicit example of a complete curve in moduli space is given in [G-H]. In [G-H] they constructed a complete curve of $M_3$ as an intersection of five hypersurfaces of the Satake compactification of $M_3$. One way to get a complete curve of $M_3$ is to find a complete one dimensional family $p : X \to B$ of plane quartics which gives a nontrivial morphism from the base space B to the moduli space $M_3$. This is because every non-hyperelliptic smooth curve of genus three can be realized as a nonsingular plane quartic and vice versa. This paper has come out from the effort to find such a complete family of plane quartics. Since nonsingular quartics form an affine space some fibers of p must be singular ones. In this paper, due to the semistable reduction theorem [M], we search singular plane quartics which can occur as singular fibers of the family above. We first list all distinct plane quartics in terms of singularities.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.269-277
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• 2000

When Persicaria thunbergii and Rumex crispus were treated with Cd($NO_3$)$_2$ and Pb($NO_3$)$_2$ of 5 or 10 mM for 5 days, the amount of bioaccumulation of $Pb^{2+}$ in the leaf of P. thunbergii was 2.87-8.08$\mu\textrm{g}$/g and that of $Cd^{2+}$ was 0.82-2.79$\mu\textrm{g}$/g. In the case of P. thunbergii, the concentration of $Pb^{2+}$ in the leaf was higher than that of $Cd^{2+}$. On the other hand, in R. crispus, the concentration of $Cd^{2+}$ and $Pb^{2+}$ were similar as follows ; 1.49$\mu\textrm{g}$/g in $Cd^{2+}$ 5mM, 2.90$\mu\textrm{g}$/g in Cd2+ 10mM, 1.83$\mu\textrm{g}$/g in $Pb^{2+}$ 5mM and 2.73$\mu\textrm{g}$/g in $Pb^{2+}$ 10mM. The remaining rate of heavy metals and the variation of pH in the cultured soil decreased as compared with control (100 % and pH 6.48) after 5 days as follows; to 77.l% and pH 6.39 in $Cd^{2+}$ 5mM, 90.2% and pH 5.79 in $Cd^{2+}$ 10 mM, 81.1% and pH 6.00 in $Pb^{2+}$ 5mM, and 85.7% and pH 5.80 in $Pb^{2+}$ 10 mM. The result of size exclusion chromatography, several phytochelatins were seperated from the extract of the leaf of both plants treated with heavy metals. The molecular mass of these phytochelatins were estimated as follows; in the case of P. thunbergii, about 4,300-8,600 da by $Cd^{2+}$ and about 3,200-9,700 da by $Pb^{2+}$, and in R. crispus, about 4,300 da by $Cd^{2+}$ and about 3,200-7,500 da by $Pb^{2+}$. In addition, $A_{254}$ of these phytochelatins were higher than $A_{280}$. [Phytochelatin, Persicaria thunbergii, Rumex crispus]

• Bulletin of the Korean Mathematical Society
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• v.43 no.3
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• pp.619-626
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• 2006

Let m be any positive integer, R be a ring with identity, $M_m(R)$ be the matrix ring of all m by m matrices eve. R and $G_m(R)$ be the multiplicative group of all n by n nonsingular matrices in $M_m(R)$. In this pape., the following are investigated: (1) for any pairwise coprime ideals ${I_1,\;I_2,\;...,\;I_n}$ in a ring R, $M_m(R/(I_1{\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $M_m(R/I_1){\times}M_m(R/I_2){\times}...{\times}M_m(R/I_n);$ and $G_m(R/I_1){\cap}I_2{\cap}...{\cap}I_n))$ is isomorphic to $G_m(R/I_1){\times}G_m(R/I_2){\times}...{\times}G_m(R/I_n);$ (2) In particular, if R is a finite ring with identity, then the order of $G_m(R)$ can be computed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.3
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• pp.243-250
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• 2009

To develop a new natural whitening agent for cosmetics, we investigated the inhibitory effects of Poria cocos Bark extracts (PCBE) and its active compound on melanogenesis. PCBE showed ROS scavenging activities in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and xanthine/xanthine oxidase system with the $IC_{50}$ values of $19.4{\pm}2.21{\mu}g$/mL and $IC_{50}=103{\pm}3.33{\mu}g$/mL, respectively. PCBE reduced intracellular tyrosinase activity about 34 % at concentration of $50{\mu}g$/mL. And PCBE reduced melanin contents of B16 melanoma cells about 51 % at concentration of $50{\mu}g$/mL without cell cytotoxicity (below $100{\mu}g$/mL). We purified one active compound from PCBE and identified its structure. It was identified as 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid, triterpene family, by $^1H$-NMR, $^{13}C$-NMR and Mass analysis. 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid showed ROS scavenging activities in DPPH radical and xanthine/xanthine oxidase system with the $IC_{50}$ values of $4.3{\pm}0.15{\mu}g$/mL and $54{\pm}1.67{\mu}g$/mL, respectively. Also, it was shown that 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid reduced intracellular tyrosinase activity about 43 % at concentration of $10{\mu}g$/mL. And it inhibited melanin synthesis in a dose dependent manner ($IC_{50}=3.6{\mu}g$/mL) without cell cytotoxicity (below $100{\mu}g$/mL). 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid inhibited tyrosinase, TRP-1 and TRP-2 expression at protein level. These results suggest that PCBE and 3-$\beta$-hydroxylanosta-7,9(11),24-trien-4-oic acid reduced melanin formation by the inhibition of tyrosinase activity and expression in B16 melanoma cells. Therefore, we suggest that PCBE could be used as a useful whitening agent.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.1
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• pp.46-56
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• 2009

The main purpose of this study was to investigate air quality trends of ambient aerosol with obtaining size-fractionated information. The suspended particulate matters were continuously collected on membrane filters and glass fiber filters by an 8-stage cascade impactor for 2 years (Sep. 2005 $\sim$ Sep. 2007) in Kyung Hee University-Global Campus. 8 ionic species ($Na^+$, ${NH_4}^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, ${NO_3}^-$, and ${SO_4}^{2-}$) were analyzed by an IC after performing proper pretreatments of each sample filter. The average concentration levels of each ion were $9.24{\mu}g/m^3$ of ${SO_4}^{2-}$, $7.35{\mu}g/m^3$ of ${NO_3}^-$, $2.81{\mu}g/m^3$ of ${NH_4}^+$, $2.11{\mu}g/m^3$ of $Ca^{2+}$, $1.65{\mu}g/m^3$ of $Cl^-$, $1.87{\mu}g/m^3$ of $Na^+$, $0.80{\mu}g/m^3$ of $Mg^{2+}$, and $0.54{\mu}g/m^3$ of $K^+$, respectively. The distribution pattern of $Na^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, and ${NO_3}^-$ was bi-modal and two peaks appeared in the range of $0.4{\sim}0.7{\mu}m$ and $3.3{\sim}4.7{\mu}m$, respectively. On the other hand, ${SO_4}^{2-}$, ${NH_4}^+$, and $K^+$ showed patterns of uni-modal distribution, mostly abounded in the fine mode group.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.12
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• pp.665-679
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• 2002

The fault diameter of a graph G is the maximum of lengths of the shortest paths between all two vertices when there are $\chi$(G) - 1 or less faulty vertices, where $\chi$(G) is connectivity of G. In this paper, we analyze the fault diameter of recursive circulant $G(2^m,2^k)$ with $k{\geq}3$. Let $ dia_{m.k}$ denote the diameter of $G(2^m,2^k)$. We show that if $2{\leq}m,2{\leq}k, the fault diameter of $G(2{\leq}m,2{\leq}k)$ is equal to $2^m-2$, and if m=k+1, it is equal to $2^k-1$. It is also shown that for m>k+1, the fault diameter is equal to di a_$m{\neq}1$(mod 2k); otherwise, it is less than or equal to$dia_{m.k+2}$.

• Journal of Environmental Science International
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• v.24 no.3
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• pp.317-322
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• 2015

The photocatalytic decomposition characteristics of toluene, acetone, and methyl mercaptan (MM) by UV reactor installed with $TiO_2$-coated perforated plane were studied. The removal efficiency of single toluene, acetone, and MM vapor was increased with increasing oxygen concentration, but decreased with increasing inlet concentration. Elimination capacity of single toluene, acetone, and MM vapor was obtained to be $628g/m^3{\cdot}day$, $1,041g/m^3{\cdot}day$, and $2,158g/m^3{\cdot}day$, respectively. Also, the photocatalytic decomposition of binary vapor consisted of toluene and acetone, toluene and MM, acetone and MM were observed. Elimination capacity of toluene mixed with acetone, toluene mixed with MM, acetone mixed with toluene, acetone mixed with MM, MM mixed with toluene, and MM mixed with acetone was $327g/m^3{\cdot}day$, $512g/m^3{\cdot}day$, $128g/m^3{\cdot}day$, $266g/m^3{\cdot}day$, $785g/m^3{\cdot}day$ and $883g/m^3{\cdot}day$, respectively. The inhibitory effect of acetone was higher than MM in photocatalytic decomposition of toluene, the inhibitory effect of toluene was higher than MM photocatalytic decomposition of acetone, and the inhibitory effect of toluene was higher than acetone in photocatalytic decomposition of MM.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.314-314
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• 1994

대상환자는 15예로, 14예에서 평가 가능하였으며 남녀비는 8:6, 중앙연령 32세(10-70세) 이었고, 대상질환은 악성골옥종 7예, 악성임파종 2예, 위암 2예, 폐암 2예, 그리고 자궁평활근육종 1예였다. rhGM-CSF 50 $\mu\textrm{g}$/$m^2$ 3예, 100 $\mu\textrm{g}$/$m^2$ 3예, 150 $\mu\textrm{g}$/$m^2$ 3예, 250 $\mu\textrm{g}$/$m^2$ 3예, 350 $\mu\textrm{g}$/$m^2$ 3예, 500 $\mu\textrm{g}$/$m^2$ 6예, 700 $\mu\textrm{g}$/$m^2$ 용량 3예에서 시행되었다. 1주기 시행한 환자는 7예, 2주기 5예, 3주기, 4주기 각각 1예씩 있다. 부작용은 50-150 $\mu\textrm{g}$/$m^2$에서 WHO grade I의 발열, 전신쇠약, 식용부진등이 관찰되었으나 grade II이상의 부작용은 없었다. 250 $\mu\textrm{g}$/$m^2$이상의 용량에서도 grade II의 발열이 관찰되었을 뿐 다른 중증의 부작용은 관찰되지 않았다. 최고용량인 700 $\mu\textrm{g}$/$m^2$ 에서도 grade II의 발열외의 중한 부작용은 관찰되지 않았다. 각 용량에 따른 백혈구 증가율(%투여제2일/투여제1일)은 130-500% 이었다. rhGM-CSF는 투여 2-4 시간후 혈중최고치 (0.42-15.4 ng/ml)가 관찰되었으며 투여 12시간까지 0.2-2 ng/ml 의 농도가 지속되었다. 소변내 rh GM-CSF 배설량은 총투여량의 1% 미만이었다.

• Rubber Technology
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• v.6 no.2
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• pp.91-98
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• 2005

Nano-sized cathode materials for high power lithium ion polymer battery are easily and economically prepared using united eutectic self-mixing method without any artificial mixing procedures of reactants and ultra-miniaturization of products. While the micro-sized $LiNi_{0.7}Co_{0.3}O_2$ exhibits the discharge capacities of 167.8 mAh/g at 0.1C and 142.5 mAh/g at 3.0C, those of the nano-sized $LiNi_{0.7}Co_{0.3}O_2$ are 170.8 mAh/g at 0.1C and 159.3 mAh/g at 3.0C. In the case of $LiCoO_2$, the micro-sized $LiCoO_2$ exhibits the discharge capacities of 134.8 mAh/g at 0.1C and 118.6 mAh/g at 5.0C. Differently, the nano-sized $LiCoO_2$ exhibits the discharge capacities of 137.2 mAh/g at 0.1C and 131.7 mAh/g at 5.0C.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.655-664
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• 1999

본 논문은 조기발병형 치주염에 이환된 환자의 immunoglobulin allotype markers(Gm)에 대한 연구를 한 것이다. 원래 이전의 논문에서 Porphyromonas gingivalis(Pg)에 대한 항체 역가를 측정하기위해 선택되었던 환자로 이는 subform I(distinctive localized juvenile periodontitis(LIP) pattern)으로부터 3명, subtype II(post-LJP pattern)으로부터 19명, subform III(localized but rapidly progressing pattern)으로부터 15명 그리고 subform Ⅳ(distinctive rapidly pregressing periodontitis(RPP)으로부터 24명을 추출하여 구성하였고, 각각 인종과 나이에 맞게 50명의 대조군을 구성했다. Gm type은 hemagglutination inhibition assay; b0b1b3b5, G3m(s), G3m(t)를 포함한 G1m(a), G1m(x), G1m(f), G2m(n), G3m(g), G3m(b)로 확인했었다. 관찰되어진 Gm haplotypes의 도수는 각각의 EOP subform에 따라 계산되었고 Gm phenotype은 각 환자에서 발견된 증가된 IgG subclass responses의 다양성에 따라 구분했다. 환자들 중에서 관찰된 9개의 Gm phenotype 은 4개의 Gm haplotype으로 나타났다. subform Ⅳ에서 관찰되어진 모든 4개의 Gm haplotype의 도수는 대조군과 유의성있는 차이가 났다. 특히 haplotype afnb(Gm(n))의 그것이 유의성있게 높았다. 더욱이 G2m(n)은 IgG4와 IgG1의 level뿐만 아니라 IgG2 level의 증가와 밀접한 관련이 있었다. Gm phenotype을 검사 할 때 IgG1+2와 IgG1+2+4모두에서 antibody level이 증가한 모든 환자가 일관되게 Gm phenotype agfnb나 axfnb를 가졌다. 결론적으로, IgG subclass response는 개인의 immunogenetic marker에 의해 조절되었고 genetic predisposition의 가능성은 EOP subform IV환자에서 관찰할 수 있었다. 더욱이 G2m(n)과 Gm phenotype agfnb나 axfnb 모두 IgG1+2 나 IgG1+2+4 antibody의 증가와 밀접한 관련이 있었다.