• Korean Journal of Mathematics
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• v.16 no.3
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• pp.425-437
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• 2008

Let P be a poset and G = G(P) be the incomparability graph of P. Stanley [7] defined the chromatic symmetric function $X_{G(P)}$ which generalizes the chromatic polynomial ${\chi}_G$ of G, and showed all coefficients are nonnegative in the e-expansion of $X_{G(P)}$ for a poset P of rank 1. In this paper, we construct a sign reversing involution on the set of special rim hook P-tableaux with some conditions. It gives a combinatorial proof for (3+1)-free conjecture of a poset P of rank 1.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.1
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• pp.55-68
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• 2001

This paper presents a new ALU architecture to minimize glitching power consumption which is appeared in the conventional one with P(carry propagation)/G(carry generation) blocks. In general, A lot of glitches generated once are propagating into the next stage of circuits to make unnecessary power dissipation. Therefore, a new ALU architecture which removes the glitches at the output of P/G blocks is presented in this paper. If a lot of glitches at the output of P/G blocks are removed, then the signal transitions caused by glitches are reduced in the sum generation block and hence power consumption is also reduced. A latch is inserted into the conventional P/G blocks to remove the glitches at the output of P/G blocks. Latch enable signal can make a role in eliminating a lot of glitches at the P/G's outputs by controlling output enable time. Experimental results from HSPICE simulations with implementing 16-b ALU show 28% reduction in glitching power consumption with negligible delay penalty.

• Communications of the Korean Mathematical Society
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• v.28 no.4
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• pp.643-647
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• 2013

Let G be a group and let $p$ be a prime number. If the set $\mathcal{A}(G)$ of all commuting automorphisms of G forms a subgroup of Aut(G), then G is called $\mathcal{A}(G)$-group. In this paper we show that any $p$-group with cyclic maximal subgroup is an $\mathcal{A}(G)$-group. We also find the structure of the group $\mathcal{A}(G)$ and we show that $\mathcal{A}(G)=Aut_c(G)$. Moreover, we prove that for any prime $p$ and all integers $n{\geq}3$, there exists a non-abelian $\mathcal{A}(G)$-group of order $p^n$ in which $\mathcal{A}(G)=Aut_c(G)$. If $p$ > 2, then $\mathcal{A}(G)={\cong}\mathbb{Z}_p{\times}\mathbb{Z}_{p^{n-2}}$ and if $p=2$, then $\mathcal{A}(G)={\cong}\mathbb{Z}_2{\times}\mathbb{Z}_2{\times}\mathbb{Z}_{2^{n-3}}$ or $\mathbb{Z}_2{\times}\mathbb{Z}_2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1633-1637
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• 2005

Five different plant cell wall degrading enzymes were tested for their ability to release p -hydroxybenzoic acid from carrot alcohol insoluble residue (AIR) and cellulose fraction. Phenolics of AIR from cell wall materi민 (CWM) in carrot were found to consist primarily of p-hydroxybenzoic acid (1,977 $\mu$g/g AIR) with minor contribution from vanillin (55.9 $\mu$g/g AIR), ferulic acid (13.6 $\mu$g/g AIR) and p-hydroxybenzaldehyde (10.6 $\mu$g/g AIR). The contents of ferulic acid in Driselase, Cellulase, Macerozyme R-200, Macerozyme R-10 and Sumyzyme MC were 2,319, 2,060, 391, 95.2, 34.1 $\mu$g/g, respectively. Incubation of Driselase with AIR released only 2.8$\%$ of the total 4 M NaOH extractable p-hydroxybenzoic acid. These results indicate that commercial five plant cell wall dograding enzymes can not release P-hydroxybenzoic acid from carrot AIR and cellulose fraction.

• Journal of the Chungcheong Mathematical Society
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• v.28 no.4
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• pp.603-614
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• 2015

For a map $p:X{\rightarrow}A$, we define and study a concept of $G^{\prime}_p$-space for a map, which is a generalized one of a G'-space. Any G'-space is a $G^{\prime}_p$-space, but the converse does not hold. In fact, $CP^2$ is a $G^{\prime}_{\delta}$-space, but not a G'-space. It is shown that X is a $G^{\prime}_p$-space if and only if $G^n(X,p,A)=H^n(X)$ for all n. We also obtain some results about $G^{\prime}_p$-spaces and homology decompositions for spaces. As a corollary, we can obtain a dual result of Haslam's result about G-spaces and Postnikov systems.

• The Mathematical Education
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• v.21 no.3
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• pp.7-11
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• 1983

A measurable function f defined on a measurable subset A of the real line R is called pth power summable on A if │f│$^{p}$ is integrable on A and the set of all pth power summable functions on A is denoted by L$^{p}$ (A). For each member f in L$^{p}$ (A), we define ∥f∥$_{p}$ =(equation omitted) For real numbers p and q where (equation omitted) and (equation omitted), we discuss the Holder's inequality ∥fg∥$_1$<∥f∥$_{p}$ ∥g∥$_{q}$ , f$\in$L$^{p}$ (A), g$\in$L$^{q}$ (A) and the Minkowski inequality ∥＋g∥$_{p}$ <∥f∥$_{p}$ ＋∥g∥$_{p}$ , f,g$\in$L$^{p}$ (A). In this paper also discuss that L$_{p}$ (A) becomes a metric space with the metric $\rho$ : L$^{p}$ (A) $\times$L$^{p}$ (A) longrightarrow R where $\rho$(f,g)=∥f-g∥$_{p}$ , f,g$\in$L$^{p}$ (A). Then, in this paper prove the Riesz-Fischer theorem, i.e., the space L$^{p}$ (A) is complete and that the space L$^{p}$ (A) is separable.

• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.27-33
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• 2007

This research investigated the effects of spherical and aspherical R.G.P lenses which was performed by optometrists in In-Cheon and Kyung-Gi region. This research survey included various questions such as the fitting status, after-care method, preliminary test. Results of the survey revealed that the optometriests sold the asperical and spherical lenses with a ratio of 7:3, respectively, and most of them did not cheked Topography, Fluorescein test by slit lamp biomicroscope, Tear Break up time test, Schirmer test and so on. And, with fitted R.G.P lenses symptoms like light odd-feeling, congestion, eye-stimulus, dimness and dryness were frequently reported. The purposes of this study are to search for the ideal fitting check of R.G.P lens and remind the most important preliminary test for contact lens fitting.

• Pediatric Infection and Vaccine
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• v.22 no.2
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• pp.81-90
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• 2015

Purpose: Group A rotavirus (RV) is most common etiologic agent of acute gastroenteritis (AGE) in children worldwide. Recently, vaccination has been introduced in several countries to reduce the disease burden caused by RV infections, but continuous surveillance of RV strains is necessary to detect the emergence of potential variants induced by vaccine-immune pressure. This study aimed to investigate the changing pattern of RV genotypes in children with AGE, following the introduction of vaccination in Korea. Methods: Genotyping of RVs by RT-PCR on the basis of VP7 and VP4 gene segment sequence was carried out on 201 rotavirus-positive stool samples, from children hospitalized with AGE between August 2009 and June 2013. We have directly sequenced PCR products and analyzed the phylogenetic tree. Results: The most prevalent G genotype was G9 (33.3%), followed by G1 (22.4%), G3 (15.9%), G2 (6.0%), G4 (3.0%), G10 (1.5%), and mixed G-type (15.4%), with some nontypeable cases (2.5%). The detected P genotypes were P[4] (45.3%), P[8] (43.8%), mixed P-type (10.4 %), and P[2] (0.5%). The G9P[4] genotype was predominantly observed in hospitalized cases in Seoul in 2010/2011, however G1P[8] has been re-emerged as the predominant genotype in the following season (P =0.004). Conclusions: It seems that the periodic fluctuation in predominance of the G1, G3, and G9 strains occurred in Korea during 2009-2013, following the introduction of RV vaccination.

• Bulletin of the Korean Mathematical Society
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• v.51 no.4
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• pp.943-948
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• 2014

Suppose that G is a finite group and H is a subgroup of G. H is said to be an ss-quasinormal subgroup of G if there is a subgroup B of G such that G = HB and H permutes with every Sylow subgroup of B; H is said to be semi-p-cover-avoiding in G if there is a chief series 1 = $G_0$ < $G_1$ < ${\cdots}$ < $G_t=G$ of G such that, for every i = 1, 2, ${\ldots}$, t, if $G_i/G_{i-1}$ is a p-chief factor, then H either covers or avoids $G_i/G_{i-1}$. We give the structure of a finite group G in which some subgroups of G with prime-power order are either semi-p-cover-avoiding or ss-quasinormal in G. Some known results are generalized.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.141-144
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• 2003

청양 및 서보광산에서 채취한 광미 및 오염된 토양에 대한 산성비를 고려한 용출실험 결과, 아연, 카드뮴 및 망간 pH 6.2-5.8, 철 pH 5.2-3.2, 코발트 pH 4.4-3.2, 구리 pH 3.2-3.0, 납과비소 pH3.0-3.5의 용출조건에서 최초로 각 원소의 용출이 발생하였다. 반응용액의 최종 pH5.0-1.5사이에서 용출되는 중금속은 이온교환형태 및 탄산염광물형태와 수반된 것이 용해된 것이다. 반응용액의 최종 pH1.5이하에서 용출되는 중금속은 철과 밀접하게 수반된 것으로 해석되었다. 청양광산과 서보광산의 광미가 pH2.0이하로 유지되는 경우가 발생한다면, 청양광산은 비소(최대 6,006$\mu\textrm{g}$/g), 아연(최대 2,503$\mu\textrm{g}$/g) 및 납(최대 29,638$\mu\textrm{g}$/g), 서보광산은 납(최대 2,258$\mu\textrm{g}$/g)과 111소(최대 874$\mu\textrm{g}$/g)의 오염확산이 크게 우려되며, 이 결과는 광미에 대한 환경복원이 필요한 것을 지시한다. 서보광산의 오염된 토양은 pH3.0까지의 산성비와 반응하는 경우에는 중금속의 오염확산이 거의 우려되지 않으며, pH3.0이하의 강산 용액과 반응한다면 아연의 오염확산이 우려된다.