• Journal of the Korean Mathematical Society
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• v.33 no.3
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• pp.625-639
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• 1996

A convex $RP^n$-structure on a smooth anifold M is a representation of M as a quotient of a convex domain $\Omega \subset RP^n$ by a discrete group $\Gamma$ of collineations of $RP^n$ acting properly on $\Omega$. When M is a closed surface of genus g > 1, then the equivalence classes of such structures form a moduli space $B(M)$ homeomorphic to an open cell of dimension 16(g-1) (Goldman [2]). This cell contains the Teichmuller space $T(M)$ of M and it is of interest to know what of the rich geometric structure extends to $B(M)$. In [3], a symplectic structure on $B(M)$ is defined, which extends the symplectic structure on $T(M)$ defined by the Weil-Petersson Kahler form.

• Bulletin of the Korean Mathematical Society
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• v.55 no.2
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• pp.533-543
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• 2018

Under the symbol ${\Omega}$ is a combination of ${\phi}_i$ ($i=1,2,3,{\ldots},n$) which has a suitable growth condition, for dimension n = 2 and $n{\geq}3$, when the initial data f belongs to homogeneous Sobolev space, we obtain the global $L^q$ estimate for maximal operators generated by operators family $\{S_{t,{\Omega}}\}_{t{\in}{\mathbb{R}}}$ associated with solution to dispersive equations, which extend some results in [27].

• Communications for Statistical Applications and Methods
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• v.10 no.3
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• pp.749-764
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• 2003

In this paper we explain that normal theory likelihood-ratio tests(z, t, $x^2$. F) for mean(s) or variance(s) can be geometrically related to volume of difference of two joint pdf's. One is an estimated joint pdf under null parameter space $\omega$ and the other is an estimated joint pdf under full parameter space $\Omega$. For explanations, ‘distance between two distributions’ is defined. We study properties of it, and derive some results on the distance between two multivariate normal distributions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.776-778
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• 2003

In the paper, the novel linear ultrasonic motor for precision position control was designed and fabricated. It was composed of two piezoelectric actuators with longitudinal ultrasonic fluctuations and shaking beam. When two AC electric fields ($Usin{\omega}t$, $Ucos{\omega}t$) were applied in two piezoelectric actuators respectively, the middle part of shaking beam had an elliptical trajectory. According to experimental results, good symmetrical characteristic of two piezoelectric actuators were obtained.

• Journal of Magnetics
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• v.20 no.3
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• pp.317-321
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• 2015

In this paper, magnetorheological fluids (MRFs) based on micro-sized iron particles dispersed in silicone oil are presented. The iron particles are modified by adding different ratios of oleic acid and lauric acid as surfactants to the suspensions. Lauric acid was found to reduce the stability of the MRFs, and more lauric acid results in a higher rate of sedimentation. Further study showed that the formation and structure of lauric acid may result in the sedimentation of micrometer-sized particles. Meanwhile, the electro-resistance of MRF in this paper shows a decrease from beyond $6000M{\Omega}$ to $190{\Omega}$ with an increase in the external field from 0 mT to 400 mT.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1193-1194
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• 2015

The volume electrical resistivity of $3.777{\times}10^{13}{\Omega}{\cdot}cm$ of dried CSPE for 660~750 days after seawater & freshwater soaking is lower than $4.011{\times}10^{13}{\Omega}{\cdot}cm$ of that before seawater soaking. The peak binding energy of oxygen and sulphur of CSPE after seawater & freshwater soaking are shifted above 1.0ev. The grass transition temperature($T_g$) of $-19.76^{\circ}C$ of seawater & freshwater soaked CSPE are lower than $-19.59^{\circ}C$ of that of non-soaked CSPE. The melting temperatures($T_m$) of seawater & freshwater soaked and non-soaked CSPE are $45.58^{\circ}C$ and $45.59^{\circ}C$, respectively.

• Journal of the Korean Mathematical Society
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• v.51 no.2
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• pp.383-402
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• 2014

We expose a pattern for establishing Friedman-Weiermann style independence results according to which there are thresholds of provability of some parameterized variants of well-partial-ordering. For this purpose, we investigate an ordinal notation system for ${\vartheta}{\Omega}^{\omega}$, the small Veblen ordinal, which is the proof-theoretic ordinal of the theory $({\prod}{\frac{1}{2}}-BI)_0$. We also show that it sometimes suffices to prove the independence w.r.t. PA in order to obtain the same kind of independence results w.r.t. a stronger theory such as $({\prod}{\frac{1}{2}}-BI)_0$.

• The Pure and Applied Mathematics
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• v.1 no.1
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• pp.25-27
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• 1994

Suppose that X is a Banach space with continuous dual $X^{**}$, ($\Omega$, $\Sigma$, ${\mu}$) is a finite measure space. f : $\Omega\;{\longrightarrow}$ $X^{*}$ is a weakly measurable function such that $\chi$$^{**}$ f $\in$ $L_1$(${\mu}$) for each $\chi$$^{**}$ $\in$ $X^{**}$ and $T_{f}$ : $X^{**}$ \longrightarrow $L_1$(${\mu}$) is the operator defined by $T_{f}$($\chi$$^{**}$) = $\chi$$^{**}$f. In this paper we study the properties of bounded $X^{*}$ - valued weakly measurable functions and bounded $X^{*}$ - valued weak＊ measurable functions.(omitted)

• East Asian mathematical journal
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• v.37 no.5
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• pp.577-584
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• 2021

Let p : X → D be a proper surjective holomorphic submersion where X is a Kähler manifold and D is the unit disc in ℂ. Let Ω be a d-closed semi-positive real (1, 1)-form on X. If each X_s := p^-1(s) for s ∈ D satisfies $-c_1(X_s)+{\Omega}{\mid}_{X_s}$ is Kähler, then the Kähler-Ricci flow twisted by ${\Omega}{\mid}_{X_s}$ has a long time solution by Cao's theorem. This family of twisted Kähler-Ricci flows induces a relative Kähler form ω(t) on the total space X. In this paper, we prove that the positivity of ω(t) is preserved along the twisted Kähler-Ricci flow.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.66-71
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• 2007

Two isolates of genus Acinetobacter were obtained from Jang-Baek waterfall in North Korea. Morphological characteristics of the isolated 2 strains were Gram-negative, aerobic and rod shape bacteria. Physiological and biochemical characterization of the isolated 2 strains were some different aspect from those of type strains. 16S rDNA sequence analysis showed that the two isolates shared 99.9% sequence similarity. Strains JB10 and $JB15^{T}$ were shown to belong to the Gammaproteobacteria and showed the highest levels of sequence similarity to Acinetobacter tandoii $4N13^{T}$ (97.3%), Acinetobacter haemolyticus $ATCC17906^{T}$ (97.2%), Acinetobacter johnsonii $DSM6963^{T}$ (97.2%), Acinetobacter junii $DSM6964^{T}$ (96.7%), Acinetobacter schindleri $LUH5832^{T}$ (97.0%) and Acinetobacter ursingii $LUH3792^{T}$ (96.6%). The major cellular fatty acid in Acinetobacter type strains and isolated strains included $C_{18:1}\;{\omega}9c\;and\;C_{16:1}\;{\omega}7c/C_{15:0}\;iso\;2OH$. Eventhough it was ascertained that the isolated strains were closely related to genus Acinetobacter, physiological and biochemical characteristics and the result of the isolated strains 16S rDNA analysis indicate some different aspects from those of type strains of genus Acinetohacter It is considered that the isolated JB10 (=KEMC 52-093) and $JB15^{T}\;(=KEMC\;52-094^{T})$ strains be new species of genus Acinetobacter. We name it as Acinetobacter koreensis sp. nov.