• Bulletin of the Korean Mathematical Society
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• v.30 no.2
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• pp.213-221
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• 1993

In this paper, we will show that the multiplicative group G in a finite ring R with identity 1 has a (B, N)-pair satisfying the following conditions; (1) G=BNB where B and N are subgroups of G. (2) B.cap.N is a normal subgroup of N and W = N/(B.cap.N), is generated by a set S = { $s_{1}$, $s_{2}$, .., $s_{k}$} where $s_{i}$.mem.N/(B.cap.N), $s_{i}$$^{2}$.iden.1 and $s_{i}$.neq.1. (3) For any s.mem.S and w.mem.W, we have sBw.contnd.BwB.cup.BswB. (4) We have sBs not .subeq. B for any s.mem.S. When G, B, N and S satisfy the above conditions, we say that the quadruple (G, B, N, S) is a Tits system. The group W is called the Weyl gorup of the Tits system.ystem.m.

• Journal of the Korean Mathematical Society
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• v.54 no.5
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• pp.1505-1519
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• 2017

Assume that M is an R-module where R is a commutative ring. A proper submodule N of M is called a weakly 2-absorbing primary submodule of M if $0{\neq}abm{\in}N$ for any $a,b{\in}R$ and $m{\in}M$, then $ab{\in}(N:M)$ or $am{\in}M-rad(N)$ or $bm{\in}M-rad(N)$. In this paper, we extended the concept of weakly 2-absorbing primary ideals of commutative rings to weakly 2-absorbing primary submodules of modules. Among many results, we show that if N is a weakly 2-absorbing primary submodule of M and it satisfies certain condition $0{\neq}I_1I_2K{\subseteq}N$ for some ideals $I_1$, $I_2$ of R and submodule K of M, then $I_1I_2{\subseteq}(N:M)$ or $I_1K{\subseteq}M-rad(N)$ or $I_2K{\subseteq}M-rad(N)$.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.2
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• pp.23-29
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• 2015

The baby-step giant-step algorithm seeks b in a discrete logarithm problem when a,c,p of $a^b{\equiv}c$(mod p) are already given. It does so by dividing p by m block of $m={\lceil}{\sqrt{p}}{\rceil}$ length and letting one giant walk straight toward $a^0$ with constant m strides in search for b. In this paper, I basically reduce $m={\lceil}{\sqrt{p}}{\rceil}$ to p/l, $a^l$ > p and replace a giant with an adult who is designed to walk straight with constant l strides. I also extend the algorithm to allow $2^k$ adults to walk simultaneously. As a consequence, the proposed algorithm quarters the execution time of the basic adult-walk method when applied to $2^k$, (k=2) in the range of $1{\leq}b{\leq}p-1$. In conclusion, the proposed algorithm greatly shorten the step number of baby-step giant-step.

• Tuberculosis and Respiratory Diseases
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• v.42 no.6
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• pp.862-870
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• 1995

Background: Oxygen free radicals have generally been considered as cytotoxic agents. On the other hand, recent results suggest that small nontoxic amounts of these radicals may act a role in intracellular signal transduction pathway and many efforts to reveal the role of these radicals as secondary messengers have been made. It is evident that the oxygen radicals are released by various cell types in response to extracellular stimuli including LPS, TNF, IL-1 and phorbol esters, all of which translocate the transcription factor $NF{\kappa}B$ from cytoplasm to nucleus by releasing an inhibitory protein subunit, $I{\kappa}B$. Activation of $NF{\kappa}B$ is mimicked by exposure to mild oxidant stress, and inhibited by agents that remove oxygen radicals. It means the cytoplasmic form of the inducible tanscription factor $NF{\kappa}B$ might provide a physiologically important target for oxygen radicals. At the same time, it is well known that LPS induces the release of oxygen radicals in neutrophil with the activation of $NF{\kappa}B$. From above facts, we can assume the expression of IL-8 and IL-$1{\beta}$ gene by LPS stimulation may occur through the activation of $NF{\kappa}B$, which is mediated through the release of $I{\kappa}B$ by increasing amounts of oxygen radicals. But definitive evidence is lacking about the role of oxygen free radicals in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. We conducted a study to determine whether oxygen radicals act a role in the expression of IL-8 and IL-$1{\beta}$ gene in mononuclear phagocytic cells. Method: Human peripheral blood monocytes were isolated from healthy volunteers. Time and dose relationship of $H_2O_2$-induced IL-8 and IL-$1{\beta}$ mRNA expression was observed by Northern blot analysis. To evaluate the role of oxygen radicals in the expression of IL-8 and IL-$1{\beta}$ mRNA by LPS stimulation, pretreatment of various antioxiants including PDTC, TMTU, NAC, ME, Desferrioxamine were done and Northern blot analysis for IL-8 and IL-$1{\beta}$ mRNA was performed. Results: In PBMC, dose and time dependent expression of IL-8 and IL-$1{\beta}$ mRNA by exogenous $H_2O_2$ was not observed. But various antioxidants suppressed the expression of LPS-induced IL-8 and IL-$1{\beta}$ mRNA expression of PBMC and the suppressive activity was most prominant when the pretreatment was done with TMTU. Conclusion: Oxygen free radical may have some role in the expression of IL-8 and IL-$1{\beta}$ mRNA of PBMC but that radical might not be $H_2O_2$.

• Communications of the Korean Mathematical Society
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• v.20 no.3
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• pp.427-436
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• 2005

Let (R, m) be a 2-dimensional regular local ring with algebraically closed residue field R/m. Let K be the quotient field of R and v be a prime divisor of R, i.e., a valuation of K which is birationally dominating R and residually transcendental over R. Zariski showed that there are finitely many simple v-ideals $m=P_0\;{\supset}\;P_1\;{\supset}\;{\cdotS}\;{\supset}\;P_t=P$ and all the other v-ideals are uniquely factored into a product of those simple ones. It then was also shown by Lipman that the predecessor of the smallest simple v-ideal P is either simple (P is free) or the product of two simple v-ideals (P is satellite), that the sequence of v-ideals between the maximal ideal and the smallest simple v-ideal P is saturated, and that the v-value of the maximal ideal is the m-adic order of P. Let m = (x, y) and denote the v-value difference |v(x) - v(y)| by $n_v$. In this paper, if the m-adic order of P is 2, we show that $O(P_i)\;=\;1\;for\;1\;{\leq}\;i\; {\leq}\;{\lceil}\;{\frac{b+1}{2}}{\rceil}\;and\;O(P_i)\;=2\;for\;{\lceil}\;\frac{b+3}{2}\rceil\;{\leq}\;i\;\leq\;t,\;where\;b=n_v$. We also show that $n_w\;=\;n_v$ when w is the prime divisor associated to a simple v-ideal $Q\;{\supset}\;P$ of order 2 and that w(R) = v(R) as well.

• Journal of Korean Society of Forest Science
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• v.73 no.1
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• pp.9-13
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• 1986

Karyotypes are described for Juniperus rigida Sieb. et zucc, in two provenances of Gyeong-nam and Choong-puk. Chromosome numbers of two provenances, are 2n=22. The most common feature of mitotic chromosomes was shown at the chromosome 7, which has secondary constriction on the short arm. And the most differential chromosome was shown at chromosome 9 from Gyeong-nam and chromosome 5 from Choong-puk provenance which bore secondary constriction. The karyotype formulae are as follows; Gyeong-nam, Jinyang provenance race is $$K(2n)=22=2A^m+2B^m+2C^m+2D^{sm}+2E^{st}+2F^m+2^{sc}G^m+2H^m+2^{sc}I^t+2J^{st}+2K^m$$ Choong-puk, Jechun provenance race is $$K(2n)=22=2A^m+2B^m+2C^m+2D^{st}+2^{sc}E^{sm}+2F^m+2^{sc}G^m+2H^m+2I^m+2J^{st}+2K^{sm}$$.

• Electrical & Electronic Materials
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• v.9 no.4
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• pp.372-378
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• 1996

The phtoreflectance(PR) spectra of B ion implanted semi-insulating(SI) GaAs were studied. Ion implantation was performed by 150keV implantation energy and 1*10/aup 12/-10$^{15}$ ions/c $m^{2}$ doses. Electronic band structure was damaged by ion implantation with above 1*10$^{13}$ ions/c $m^{2}$ dose. When samples were annealed, " peak was observed at 30-40meV below band gap( $E_{g}$). It should be noted that this energy is close to the ionization energies of S $i_{As}$ , and GeAs in G $a_{As}$ which are also found as impurities in LEC GaAs, it is therefore possible that this feature is related to S $i_{As}$ , or G $e_{As}$ and B ions by implanted defect associated with them. From PR spectra of etched samples which is as-implanted by 1*10$^{14}$ and 1*10$^{15}$ ions/c $m^{2}$ dose, the depth of destroyed electronic band structure was from surface to 0.2.mu.m below surface.nic band structure was from surface to 0.2.mu.m below surface.

• YAKHAK HOEJI
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• v.36 no.5
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• pp.496-505
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• 1992

The correlation between GABA receptors($GABA_A$ and $GABA_B$ receptor) and benzodiazepine receptor on the saline infusion-induced micturition reflex contraction was studied in the female rat. To investigate the effect of ${\gamma}-aminobutyric$ acid(GABA) on the micturition reflex, exogenous GABA(10 mg/kg) and GABA transaminase inhibitor(aminooxyacetic acid; AOAA $1\;{\mu}g$) were administered intravenously(i.v.) and intracerebroventriculary(i.c.v.), respectively. In result, both GABA and AOAA inhibited the saline induced micturition reflex contraction. This AOAA induced inhibition of micturition reflex was blocked by both bicuculine. $GABA_A$ receptor antagonist, and Ro 15-1788, benzodiazepine receptor antagonist. Muscimol, $GABA_A$ receptor antagonist($0.1\;{\mu}g$ i.c.v., $3\;{\mu}g$ intrathecal; i.t., 1 mg/kg i.v.) and baclofen, $GABA_A$ receptor agonist($1\;{\mu}g$ i.c.v., $3\;{\mu}g$ i.t., 1 mg/kg i.v.) also inhibited the bladder contraction. Pretreatment of bicuculline($1\;{\mu}g$ i.c.v.), but not of 5-aminovaleric acid(AVA, $1\;{\mu}g$ i.c.v.), $GABA_B$ receptor antagonist blocked the central inhibition of muscimol. These inhibitory effects were reversed by Ro15-1788 but were potentiated by flurazepam, benzodiazepine receptor antagonist. On the other hand, the inhibitory effects of baclofen were not affected by Ro 15-1788. Diazepam and flurazepam also inhibited the micturition reflex contraction when they were administered $3\;{\mu}g$ i.c.v., $10\;{\mu}g$ i.t., $10\;{\mu}M$, $30\;{\mu}M$ transurethrally, respectively. In conclusion, these results suggest that the micturition reflex is mediated by $GABA_A$, $GABA_B$ receptor and benzodiazepine receptor. The bezodiazepines increase the receptor binding of GABA to the $GABA_A$ receptor, so that the benzodiiazepines show the synergistic effect on the inhibition of the micturition reflex contraction, but not to the $GABA_B$ receptor.

• Bulletin of the Korean Mathematical Society
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• v.57 no.3
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• pp.803-813
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• 2020

Let M be a finitely generated G-projective R-module over a PVMD R. We prove that M is projective if and only if the canonical map θ : M⨂_R M^∗ → Hom_R(Hom_R(M, M), R) is a surjective homomorphism. Particularly, if G-gldim(R) ⩽ ∞ and Extⁱ_R(M, M) = 0 (i ⩾ 1), then M is projective.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.303-308
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• 2010

Pseudo-first-order rate constants ($k_{obsd}$) have been measured spectrophotometrically for nucleophilic substitution reactions of 4-nitrophenyl benzoate (5a), 4-nitrophenyl 4-methoxybenzoate (5b), and 4-nitrophenyl 4-hydroxybenzoate (5c) with alkali metal ethoxides, $EtO^-M^+$ ($M^+=Li^+$, $Na^+$ and $K^+$) in anhydrous ethanol (EtOH) at $25.0{\pm}0.1^{\circ}C$. The plots of $k_{obsd}$ vs. [$EtO^-M^+$] exhibit upward curvatures in all cases, indicating that $M^+$ ions catalyze the reactions and ionpaired $EtO^-M^+$ species are more reactive than dissociated $EtO^-$. Second-order rate constants for reactions with dissociated $EtO^-$ and ion-paired $EtO^-M^+$ (i.e., $k_{EtO^-}$ and $k_{EtO^-M^+}$, respectively) have been calculated from ion-pair treatment for the reactions of 5a and 5b. However, such ion-pair treatment has failed to determine $k_{EtO^-}$ and $k_{EtO^-M^+}$ values for the reactions of 5c. It has been concluded that reactions of 5a and 5b are catalyzed by one metal ion, which increases electrophilicity of the reaction center through coordination on the carbonyl oxygen. In contrast, reactions of 5c have been suggested to involve two metal ions, i.e., the one coordinated on the carbonyl oxygen increases the electrophilicity of the reaction center while the other one associated on the phenoxy oxygen decreases the charge repulsion between the anionic reagents (i.e., $EtO^-$ and deprotonated 5c). It has been found that the rate equation derived from the mechanism involving two metal ions fits nicely to the kinetic results obtained for the reactions of 5c.