• Korean Journal of Mathematics
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• 제1권
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• pp.55-64
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• 1993

• Korean Journal of Mathematics
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• 제3권1호
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• pp.99-106
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• 1995

• Kyungpook Mathematical Journal
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• 제32권2호
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• pp.257-261
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• 1992

• East Asian mathematical journal
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• 제10권1호
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• pp.85-90
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• 1994

• 한국수학사학회:학술대회논문집
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• 한국수학사학회 1999년도 가을학술발표회 논문초록집
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• pp.7-7
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• 1999

• 대한수학회논문집
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• 제25권3호
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• pp.349-364
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• 2010

P. M. Cohn called a ring R reversible if whenever ab = 0, then ba = 0 for a, $b\;{\in}\;R$. Commutative rings and reduced rings are reversible. In this paper, we extend the reversible condition of a ring as follows: Let R be a ring and $\alpha$ an endomorphism of R, we say that R is right (resp., left) $\alpha$-shifting if whenever $a{\alpha}(b)\;=\;0$ (resp., $\alpha{a)b\;=\;0$) for a, $b\;{\in}\;R$, $b{\alpha}{a)\;=\;0$ (resp., $\alpha(b)a\;=\;0$); and the ring R is called $\alpha$-shifting if it is both left and right $\alpha$-shifting. We investigate characterizations of $\alpha$-shifting rings and their related properties, including the trivial extension, Jordan extension and Dorroh extension. In particular, it is shown that for an automorphism $\alpha$ of a ring R, R is right (resp., left) $\alpha$-shifting if and only if Q(R) is right (resp., left) $\bar{\alpha}$-shifting, whenever there exists the classical right quotient ring Q(R) of R.

• Structural Engineering and Mechanics
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• 제90권4호
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• pp.391-401
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• 2024

The present study focuses on the effect of extension-bending coupling on the elastic stability (buckling) of laminated composite plates. These plates will be loaded under uni-axial or bi-axial in-plane mechanical loads, especially in the orthotropic or anti-symmetric cross-angle cases. The main objective is to find a limit where we can approximate the elastic stability behavior of angularly crossed anti-symmetric plates by the simple behavior of specially orthotropic plates. The contribution of my present study is to predict the explicit effect of extension-flexion coupling on the elastic stability of this type of panel. Critically, a parametric study is carried out, involving the search for the critical buckling load as a function of deformation mode, aspect ratio, plate anisotropy ratio and finally the study of the effect of lamination angle and number of layers on the contribution of extension-flexure coupling in terms of plate buckling stability. We use first-order shear deformation theory (FSDT) with a correction factor of 5/6. Simply supported conditions along the four boundaries are adopted where we can develop closed-form analytical solutions obtained by a Navier development.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제23권1호
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• pp.53-59
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• 2016

Let G be a finite group containing a non-abelian Sylow 2-subgroup. We elementarily show that every G-Galois field extension L/K has a hyperbolic trace form in the presence of root of unity.

• 대한수학회논문집
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• 제10권3호
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• pp.519-525
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• 1995

By using an exact sequence of extension groups corresponding to an isogeny of a Drinfeld module we investigate which extension classes are coming from Hom(G,C). In the last section of this paper an example was given where the connecting homomorphism can be explictly computed.

• 대한수학회지
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• 제31권4호
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• pp.691-702
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• 1994

Let X be a normed linear space, M a subspace of X, and V a subspace of the dual space $X^*$. In [3], we studied the Hahn-Banach extension property in V. Here we give the definition and a characterization of the Hahn-Banach extension property in V.