• Journal of applied mathematics & informatics
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• v.30 no.5_6
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• pp.1051-1065
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• 2012

In this paper, the global stability and almost periodicity are investigated for generalized Hopfield neural networks with time-varying neutral delays. Some sufficient conditions are obtained for the existence and globally exponential stability of almost periodic solution by employing fixed point theorem and differential inequality techniques. The results of this paper are new and complement previously known results. Finally, an example is given to demonstrate the effectiveness of our results.

• Kyungpook Mathematical Journal
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• v.52 no.3
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• pp.279-290
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• 2012

In this paper we present some results on absolute almost generalized N$\ddot{o}$rlund summability of orthogonal series. The most important corollaries of the main results also are deduced.

• Journal of the Chungcheong Mathematical Society
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• v.30 no.4
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• pp.387-396
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• 2017

Our aim is to study covariant derivative with respect to complete and vertical lifts of generalized almost r-contact structure in tangent bundle.

• Honam Mathematical Journal
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• v.46 no.4
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• pp.522-537
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• 2024

In this article, we research the conditions for invariant sub-manifolds in an almost 𝛼-cosymplectic (𝜅, 𝜇, 𝜈) space to be pseudo-parallel, Ricci-generalized pseudo-parallel and 2-Ricci-generalized pseudo-parallel. We think that the results for the relations among the functions will contribute to differential geometry.

• Journal of the Korean Mathematical Society
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• v.41 no.5
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• pp.865-874
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• 2004

The present paper treats with a subfoliation of a CR-foliation F on an almost Hermitian manifold M. When M is locally conformal almost Kahler, it has three OR-foliations. We show that a CR-foliation F on such manifold M admits a canonical subfoliation D(1/ F) defined by its totally real subbundle. Furthermore, we investigate some cohomology classes for D(1/ F). Finally, we construct a new one from an old locally conformal almost K hler (in particular, an almost generalized Hopf) manifold.

• Honam Mathematical Journal
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• v.43 no.4
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• pp.571-586
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• 2021

The present paper deals with the study of generalized quasi-conformal curvature tensor inside the setting of (𝑘, 𝜇)'-almost Kenmotsu manifold with respect to 𝜂-Ricci soliton. Certain consequences of these curvature tensor on such manifold are likewise displayed. Finally, we illustrate some examples based on this study.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.925-930
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• 1994

We consider statistical properties of the generalized Capon's method. It is observed that the estimation error of the generalized Capon's method has almost the same variance as the MUSIC method, although the generalized Capon's method yields a slightly biased estimate.

• Communications of the Korean Mathematical Society
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• v.34 no.3
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• pp.921-934
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• 2019

The object of the present paper is to study generalized pseudo-projectively symmetric manifolds and Einstein generalized pseudo-projectively symmetric manifolds. Finally, the existence of generalized pseudo-projectively symmetric manifolds have been proved by two non-trivial examples.

• Honam Mathematical Journal
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• v.42 no.1
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• pp.123-137
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• 2020

The object of the present paper is to study certain geometrical properties of the submanifolds of generalized Sasakian space-forms. We deduce some results related to the invariant and anti-invariant slant submanifolds of the generalized Sasakian spaceforms. Finally, we study the properties of the sectional curvature, totally geodesic and umbilical submanifolds of the generalized Sasakian space-forms. To prove the existence of almost semiinvariant and anti-invariant submanifolds, we provide the non-trivial examples.

• Kyungpook Mathematical Journal
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• v.58 no.1
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• pp.137-148
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• 2018

In the present paper we prove that in an almost Kenmotsu manifold with generalized $(k,{\mu})^{\prime}-nullity$ distribution the three conditions: (i) the Ricci tensor of $M^{2n+1}$ is of Codazzi type, (ii) the manifold $M^{2n+1}$ satisfies div C = 0, (iii) the manifold $M^{2n+1}$ is locally isometric to $H^{n+1}(-4){\times}R^n$, are equivalent. Also we prove that if the manifold satisfies the cyclic parallel Ricci tensor, then the manifold is locally isometric to $H^{n+1}(-4){\times}\mathbb{R}^n$.