• Bulletin of the Korean Mathematical Society
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• v.55 no.2
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• pp.405-413
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• 2018

In this work, we use the Faber polynomial expansions to find upper bounds for the coefficients of analytic bi-univalent functions in subclass $\Sigma({\tau},{\gamma},{\varphi})$ which is defined by subordination conditions in the open unit disk ${\mathbb{U}}$. In certain cases, our estimates improve some of those existing coefficient bounds.

• Kyungpook Mathematical Journal
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• v.51 no.2
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• pp.217-232
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• 2011

Differential subordination and superordination results are obtained for multivalent meromorphic functions associated with the Liu-Srivastava linear operator in the punctured unit disk. These results are derived by investigating appropriate classes of admissible functions. Sandwich-type results are also obtained.

• Kyungpook Mathematical Journal
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• v.52 no.2
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• pp.209-222
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• 2012

In this paper, we obtain some applications of first order differential subordination and superordination results involving the operator $J_{s,b}^{{\lambda},p}$ for certain normalized p-valent analytic functions associated with that operator.

• Kyungpook Mathematical Journal
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• v.49 no.4
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• pp.631-646
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• 2009

In the present investigation, we introduce new classes of p-valent meromorphic functions defined by Liu-Srivastava linear operator and the multiplier transform and study their properties by using certain first order differential subordination and superordination.

• Kyungpook Mathematical Journal
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• v.58 no.2
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• pp.257-270
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• 2018

The well-known theory of differential subordination developed by Miller and Mocanu is applied to obtain several inclusions between $Carath{\acute{e}}odory$ functions and starlike functions. These inclusions provide sufficient conditions for normalized analytic functions to belong to certain class of Ma-Minda starlike functions.

• Kyungpook Mathematical Journal
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• v.52 no.1
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• pp.21-32
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• 2012

In this paper a new subclass of multivalent functions with negative coefficients defined by Cho-Kwon-Srivastava operator is introduced. Coefficient estimate and inclusion relationships involving the neighborhoods of p-valently analytic functions are investigated for this class. Further subordination result and results on partial sums for this class are also found.

• Honam Mathematical Journal
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• v.40 no.3
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• pp.391-400
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• 2018

The object of this paper to construct a new class $$A^m_{{\mu},{\lambda},{\delta}}({\alpha},{\beta},{\gamma},t,{\Psi})$$ of bi-univalent functions of complex order defined in the open unit disc. The second and the third coefficients of the Taylor-Maclaurin series for functions in the new subclass are determined. Several special consequences of the results are also indicated.

• Honam Mathematical Journal
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• v.40 no.3
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• pp.433-446
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• 2018

In this present investigation, we introduce a new class of harmonic univalent functions of the form $f=h+{\bar{g}}$ in the open unit disk ${\Delta}$. We get basic properties, like, necessary and sufficient convolution conditions, distortion bounds, compactness and extreme points for these classes of functions.

• Kyungpook Mathematical Journal
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• v.49 no.2
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• pp.265-281
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• 2009

In the present paper, we introduce and investigate a new subclass of multivalent functions associated with the Cho-Kwon-Srivastava operator $\tau^{\lambda}_p(a,c)$. Such results as inclusion relationships, convolution properties and criteria for starlikeness are proved. Relevant connections of the results presented here with those obtained in earlier works are also pointed out.

• Bulletin of the Korean Mathematical Society
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• v.57 no.6
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• pp.1529-1539
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• 2020

The present work is aimed at presenting some characteristic properties of functions that map open unit disk onto a lune in the right half plane. Furthermore, we introduce subclasses of functions with boundary and radius rotations which are related to crescent regions. Some useful results, which include coefficient inequalities and some subordination properties associated with these subclasses are derived. Consequently, related problems concerning these classes are also studied.