• 충청수학회지
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• 제13권2호
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• pp.71-79
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• 2001

We study only free actions of finite abelian groups G on the 3-dimensional nilmanifold, up to topological conjugacy. we shall deal with only one out of 15 distinct almost Bieberbach groups up to Seifert local invariant.

• 충청수학회지
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• 제32권3호
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• pp.365-381
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• 2019

We study free actions of finite nonabelian groups on 3-dimensional nilmanifolds with the first homology ${\mathbb{Z}}^2{\oplus}{\mathbb{Z}}_2$, up to topological conjugacy. We show that there exist three kinds of nonabelian group actions in ${\pi}_1$, two in ${\pi}_2$ or ${\pi}_{5,i}$(i = 1, 2, 3), one in the other cases, and clarify what those groups are.

• 한국운동역학회지
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• 제14권1호
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• pp.65-81
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• 2004

The purposes of this study were to determine the functions of actions of the limbs during each of the three support phases of the triple jump and their relationships with the performance of the triple jump. Four elite male triple jumpers were participated as subjects. The Pearson product moment correlation coefficient were used to determine and compare the relationships between the change in each component of the normalized angular momentum of the whole body about center of gravity and the actions of the extremities during different support phases. A level of significance at $\alpha$=.05 was set. After analyzing the angular momentum and correlation during support phase of the hop, step, and jump, the following findings are obtained: The actions of the arms created a side-somersaulting angular momentum about the whole body center of gravity toward the side of the free leg during the support phase of the step, and a somersaulting angular momentum about the whole body center of gravity during each support phase. The action of the free leg created a somersaulting angular momentum about the whole body center of gravity during the support phases of the hop and step.

• 충청수학회지
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• 제14권2호
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• pp.27-35
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• 2001

We shall deal with ten cases out of 15 distinct almost Bieberbach groups up to Seifert local invariant. In those cases we will show that if G is a finite abelian group acting freely on the standard nilmanifold, then G is cyclic, up to topological conjugacy.

• 대한수학회지
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• 제56권1호
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• pp.285-287
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• 2019

• 대한약리학회지
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• 제22권2호
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• pp.135-143
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• 1986

저자는 적출관류 토끼 신장기능에서 칼슘의 역할과 furosemide의 이뇨작용에 미치는 영향을 관찰하여 다음과 같은 결과를 얻었다. hydralazine놔 verapamil을 주로 신혈관 저항의 감소로 이뇨작용을 나타냈다. furosemide를 hydralazine 또는 verapamil 병합투여시 뚜렷한 이뇨작용이 나타났으며 두군 사이에 차이는 없었다. quinidine은 신혈관 수축을 일으켰으나 이뇨작용이 나타났으며 furosemide의 이뇨작용을 항진시켰다. 칼슘제외된 관류액으로 관류시 칼슘은 신혈관 수축에도 불구하고 이뇨작용이 나타났으며 furosemide의 이뇨작용을 항진시켰다. quinidine은 칼슘이 제외된 상태에서 신장기능 및 furosemide의 이뇨작용에 영향을 미 치지 못하였으나 calcium 병합투여시 과도한 신혈관 수축으로 항 이뇨작용을 보였다. verapamil은 칼슘이 제외된 상태에서 약간의 이뇨작용을 보였지만 칼슘 및 furosemide의 이뇨작용을 변화시키지 못하였다. 이상의 성적은 적출관류 토끼 신장에서 칼슘, verapamil 및quinidine이 이뇨작용이 있으며 칼슘은 furosemide의 이뇨작용을 항진시킨다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
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• pp.3-10
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• 2002

Recently, arches are used structurally because of their high in-plane stiffness and strength, which result from their ability to transmit most of the applied loading by axial forces actions, so that the bending actions are reduced. On the other hand, the resistances of arches to (out-of-plane,) flexural-torsional behavior depend on the rigidities EI/sub y/, for lateral bending, GJ for Uniform torsion, and EI/sub w/ for warping torsion which are related to axial stress for flexural-torsional behavior. The resistance of an arch to out-of-plane behavior may be reduced by its in-plane curvature, and so it may require significant lateral bracing. Thus. it is supposed that In-plane preloading which cause an axial stress, have an effect on out-of-plane free vibration behavior of arches. Because axial stresses caused increase or decrease out-of-plane stiffness. But study about this substance is insufficient. In this thesis, We will study an effect of preloading on lateral free vibration of arches, using finite element method based on Kang and Yoo's curved beam theory (about curved beam element have 7 degree of freedom including warping) with FORTRAN programming.

• 대한수학회지
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• 제34권2호
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• pp.453-467
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• 1997

A transitive permutation representation of a group G is said to be multiplicity-free if all of its irreducible constituents are distinct. The character corresponding to the action is called the permutation character, given by $(1_H)^G$, where H is the stabilizer of a point. Multiplicity-free permutation characters are of interest in the study of centralizer algebras and distance-transitive graphs, and all finite simple groups are known to have such characters. In this article, we extend to the alternating groups the result of J. Saxl who determined the multiplicity-free permutation representations of the symmetric groups. We classify all subgroups H for which $(1_H)^An, n > 18$, is multiplicity-free.

• 대한수학회지
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• 제47권3호
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• pp.601-631
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• 2010

In [6] and [7], we introduced graph von Neumann algebras which are the (groupoid) crossed product algebras of von Neumann algebras and graph groupoids via groupoid actions. We showed that such crossed product algebras have the graph-depending amalgamated reduced free probabilistic properties. In this paper, we will consider a scalar-valued $W^*$-probability on a given graph von Neumann algebra. We show that a diagonal graph $W^*$-probability space (as a scalar-valued $W^*$-probability space) and a graph W¤-probability space (as an amalgamated $W^*$-probability space) are compatible. By this compatibility, we can find the relation between amalgamated free distributions and scalar-valued free distributions on a graph von Neumann algebra. Under this compatibility, we observe the scalar-valued freeness on a graph von Neumann algebra.

• 대한수학회보
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• 제31권2호
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• pp.167-172
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• 1994

For a given $C^{*}$-dynamical system (A, G, .alpha.) with a G-simple $C^{*}$-algebra A (that is A has no proper .alpha.-invariant ideal) many authors have studied the simplicity of a $C^{*}$-crossed product A $x_{\alpha{r}}$ G. In [1] topological freeness of an action is shown to guarantee the simplicity of the reduced $C^{*}$-crossed product A $x_{\alpha{r}}$ G when A is G-simple. In this paper we investigate the pure infiniteness of a simple $C^{*}$-crossed product A $x_{\alpha}$ G of a purely infinite simple $C^{*}$-algebra A and a topologically free action .alpha. of a finite group G, and find a sufficient condition in terms of the action on the spectrum of the multiplier algebra M(A) of A. Showing this we also prove that some extension of a topologically free action is still topologically free.