• Communications of the Korean Mathematical Society
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• v.32 no.1
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• pp.165-173
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• 2017

In this paper, we prove that the automorphism group of a quasi-homogeneous properly convex affine domain in ${\mathbb{R}_n}$ acts transitively on the set of all the extreme points of the domain. This set is equal to the set of all the asymptotic cone points coming from the asymptotic foliation of the domain and thus it is a homogeneous submanifold of ${\mathbb{R}_n}$.

• Journal of the Korean Mathematical Society
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• v.42 no.3
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• pp.485-498
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• 2005

In this article we show that every quasi-homogeneous convex affine domain whose boundary is everywhere differentiable except possibly at a finite number of points is either homogeneous or covers a compact affine manifold. Actually we show that such a domain must be a non-elliptic strictly convex cone if it is not homogeneous.

• Bulletin of the Korean Mathematical Society
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• v.55 no.1
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• pp.187-204
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• 2018

Let $R={\bigoplus}_{{\alpha}{\in}{\Gamma}}\;R_{\alpha}$ be a graded integral domain, H be the set of nonzero homogeneous elements of R, and ${\star}$ be a semistar operation on R. The purpose of this paper is to study the properties of $quasi-Pr{\ddot{u}}fer$ and UMt-domains of graded integral domains. For this reason we study the graded analogue of ${\star}-quasi-Pr{\ddot{u}}fer$ domains called $gr-{\star}-quasi-Pr{\ddot{u}}fer$ domains. We study several ring-theoretic properties of $gr-{\star}-quasi-Pr{\ddot{u}}fer$ domains. As an application we give new characterizations of UMt-domains. In particular it is shown that R is a $gr-t-quasi-Pr{\ddot{u}}fer$ domain if and only if R is a UMt-domain if and only if RP is a $quasi-Pr{\ddot{u}}fer$ domain for each homogeneous maximal t-ideal P of R. We also show that R is a UMt-domain if and only if H is a t-splitting set in R[X] if and only if each prime t-ideal Q in R[X] such that $Q{\cap}H ={\emptyset}$ is a maximal t-ideal.

• Advances in materials Research
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• v.9 no.4
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• pp.289-309
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• 2020

The aim of the present investigation is to examine the propagation of plane harmonic waves in transversely isotropic homogeneous magneto visco thermoelastic rotating medium with fractional order heat transfer and two temperature. It is found that, for two dimensional assumed model, there exist three types of coupled longitudinal waves (quasi-longitudinal, quasi-transverse and quasi-thermal) in frequency domain. phase velocities, specific loss, penetration depth, attenuation coefficients of various reflected waves are computed and depicted graphically. The effects of viscosity and fractional order parameter by varying different values are represented graphically.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.4
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• pp.151-155
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• 2007

Quasi-phase-matched (QPM) second harmonic generation (SHG) waveguide devices for a green light generation were fabricated by a periodically patterned electrode on the +Z crystal surface and homogeneous LiCl solution using a 5 mol% MgO doped congruent z-cut lithium niobate crystals. Using selective chemical etching, we confirmed the periodic (${\sim}6.8{\mu}m$) domain inverted structure and measured SHG properties of fabricated periodically poled MgO : $LiNbO_3$ ridge-type waveguides.

• Journal of the Korean Home Economics Association
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• v.41 no.12
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• pp.53-68
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• 2003

The purpose of this study was to develop lesson plans and teaching materials applying practical reasoning instruction for the 7th home economics curriculum content, and to test the effect of practical reasoning instruction on morality of middle school students. This study is a quasi-experimental research with a pretest-posttest design. Practical reasoning instruction for experimental group and traditionally lecture oriented instruction for comparison group were input, and tested the statistical differences between two groups before and after the treatment. The subjects for this study were 8th grade students of a middle school located in Kwangju city. Two classes of 76 students homogeneous in characteristics and academic record for each experimental and comparison group were assigned. Instrument used for this study was a revised moral indicator, that was developed by KEDI(2001). Spss/win for 10.0 statistics program was used for analysis of data. ANCOVA was done for testing statistical difference between pretest and posttest of experiment group and comparison group. Result of study which showed statistically significant difference between groups were：1. Virtue of "responsibility for words and deeds"(from 3.22 to 3.61 for experimental group and from 3.27 to 3.26 for comparison group) in domain of responsibility and cooperation, and virtue of "punctuality"(from 3.59 to 3.76 for experimental group and from 3.41 to 3.28 for comparison group) in domain of trustworthiness, 2. Virtue of "conversation etiquette"(from 3.47 to 3.67 for experimental group and from 3.28 to 3.31 for comparison group) in domain of caring for others, 3. Virtue of "forgiveness other′s mistakes"(from 3.32 to 3.65 for experimental group and from 3.33 to 3.25 for comparison group) in domain of kindness, concession, forgiveness, and virtue of "volunteering activity"(from 2.89 to 3.71 for experimental group and from 3.36 to 3.45 for comparison group) in domain of compassion and service, 4. Virtue of "equip the convenient facility for handicapped"(from 4.19 to 4.29 for experimental group and from 4.17 to 3.91 for comparison group) in domain of equality and human rights, virtue of "recovering selfness for own community"(from 2.34 to 2.79 for experimental group and from 2.14 to 2.29 for comparison group), virtue of "opposing way of accomplishing purpose by an means"(from 3.27 to 3.31 for experimental group and from 3.47 to 3.05 for comparison group), virtue of "opposing election of considering acquaintance"(from 3.35 to 3.56 for experimental group and from 3.12 to 3.14 for comparison group) in domain of fairness, and virtue of "eradication of military force or violence among countries"(from 3.49 to 3.57 for experimental group and from 3.38 to 3.05 for comparison group) in domain of love for humanity. The morality of experimental group was improved more than that of comparison group in all of above items. From the results of this study, following conclusion was drawn. Practical reasoning instruction in home economics is effective in raising students′ virtue and value of responsibility in words and deeds, trustworthiness in punctuality, courtesy of not interrupting conversation, forgiveness of other′s mistakes, volunteering activity, equity for handicapped, fairness opposing selfness for own community, fairness opposing way of accomplishing purpose by all means, fairness opposing election of considering acquaintance, and love for humanity opposing war.