• Korean Journal of Mathematics
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• 제10권2호
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• pp.157-166
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• 2002

We show that the contact conformal curvature tensor on 3-dimensional Sasakian manifold always vanishes. We also prove that if the contact conformal curvature tensor vanishes on a 3-dimensional locally ${\varphi}$-symmetric contact metric manifold M, then M is a Sasakian space form.

• 한국산업정보학회논문지
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• 제7권3호
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• pp.89-94
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• 2002

본 논문은 주로 개 f-코심플렉틱 다양체를 다룬다. 이 개념은 개 코심플렉틱 다양체와 개 겐모츠 다양체를 포함한다. 개 코심플렉틱 다양체는 ［1］에서 도입된 이래 ［2］, ［3］, ［4］ 등 여러 학자들에 의해 연구되어져 왔으며 개 겐모츠 다양체는 ［5］에서 도입된 이래 ［6］, ［7］ 등에서 연구되어져 왔다. 본 논문에서는 개f-코심플렉틱 다양체의 접촉 초함수에 의해 정의되는 정규 엽층구조의 기하학적 성질을 연구한다. 본 논문의 목적은 ［8］, ［9］에서 얻은 성과를 확장하는 것이다.

• 호남수학학술지
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• 제41권4호
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• pp.669-682
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• 2019

The objective of this paper is to introduce and study Einstein-like para-Kenmotsu manifolds. For a para-Kenmotsu manifold to be Einstein-like, a necessary and sufficient condition in terms of its curvature tensor is obtained. We also obtain the scalar curvature of an Einstein-like para-Kenmotsu manifold. A necessary and sufficient condition for an almost para-contact metric hypersurface of a locally product Riemannian manifold to be para-Kenmotsu is derived and it is shown that the para-Kenmotsu hypersurface of a locally product Riemannian manifold of almost constant curvature is always Einstein.

• Korean Journal of Mathematics
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• 제27권3호
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• pp.691-705
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• 2019

In the present paper is to classify Beta-almost (${\beta}$-almost) Ricci solitons and ${\beta}$-almost gradient Ricci solitons on almost $CoK{\ddot{a}}hler$ manifolds with ${\xi}$ belongs to ($k,{\mu}$)-nullity distribution. In this paper, we prove that such manifolds with V is contact vector field and $Q{\phi}={\phi}Q$ is ${\eta}$-Einstein and it is steady when the potential vector field is pointwise collinear to the reeb vectoer field. Moreover, we prove that a ($k,{\mu}$)-almost $CoK{\ddot{a}}hler$ manifolds admitting ${\beta}$-almost gradient Ricci solitons is isometric to a sphere.

• 대한수학회논문집
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• 제38권1호
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• pp.205-221
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• 2023

The main goal of the paper is the introduction of the notion of conformal hemi-slant submersions from almost contact metric manifolds onto Riemannian manifolds. It is a generalization of conformal anti-invariant submersions, conformal semi-invariant submersions and conformal slant submersions. Our main focus is conformal hemi-slant submersion from cosymplectic manifolds. We tend also study the integrability of the distributions involved in the definition of the submersions and the geometry of their leaves. Moreover, we get necessary and sufficient conditions for these submersions to be totally geodesic, and provide some representative examples of conformal hemi-slant submersions.

• East Asian mathematical journal
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• 제8권1호
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• pp.55-58
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• 1992

• 대한수학회지
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• 제21권2호
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• pp.249-255
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• 1984

• 대한수학회논문집
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• 제8권3호
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• pp.455-465
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• 1993

• 대한수학회논문집
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• 제8권4호
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• pp.689-697
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• 1993

• Kyungpook Mathematical Journal
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• 제32권1호
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• pp.141-148
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• 1992