• Journal of applied mathematics & informatics
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• 제42권4호
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• pp.997-1006
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• 2024

In this paper, making use of symmetric differential operator, we introduce a new class of ℓ-symmetric - mutually adjoint functions. To make this study more comprehensive and versatile, we have used a differential operator involving three-parameter extension of the well-known Mittag-Leffler functions. Mainly we investigated the inclusion relation and subordination conditions which are the main results of the paper. To establish connections or relations with earlier studies, we have presented applications of main results as corollaries.

• 호남수학학술지
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• 제40권3호
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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.

• 대한수학회논문집
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• 제10권2호
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• pp.401-407
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• 1995

The best constants for two distinct weak-type inequalities for martingales and their differential subordinates with values in some spaces isomorphic to a Hilbert space are shown to be the same. This extends the result of Burkholder shown in the Hilbert space setting.

• Korean Journal of Mathematics
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• 제7권1호
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• pp.85-101
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• 1999

Let $p$ be analytic in the unit disc U and let $q$ be univalent in U. In addition, let ${\Omega}$ be a set in C and let ${\psi}:c^3{\times}U{\rightarrow}C$. The author determines conditions on ${\psi}$ so that $$\{{\psi}(p(z),zp^{\prime}(z),z^2p^{{\prime}{\prime}}(z);z){\mid}z{\in}U\}{\subset}{\Omega}{\Rightarrow}p(U){\subset}q(U)$$. Applications of this result to differential inequalities, differential subordinations and integral inequalities are presented.

• 대한수학회보
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• 제53권1호
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• pp.215-225
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• 2016

We consider a sufficient condition for w(z), analytic in ${\mid}z{\mid}$ < 1, to be bounded in ${\mid}z{\mid}$ < 1, where $w(0)=w^{\prime}(0)=0$. We apply it to the meromorphic starlike functions. Also, a certain Briot-Bouquet differential subordination is considered. Moreover, we prove that if $p(z)+zp^{\prime}(z){\phi}(p(z)){\prec}h(z)$, then $p(z){\prec}h(z)$, where $h(z)=[(1+z)(1-z)]^{\alpha}$, under some additional assumptions on ${\phi}(z)$.

• 대한수학회논문집
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• 제33권2호
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• pp.445-458
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• 2018

In this article we study the inclusion properties of the Bessel-Struve kernel functions in the Janowski class. In particular, we find the conditions for which the Bessel-Struve kernel functions maps the unit disk to right half plane. Some open problems with this aspect are also given. The third order differential subordination involving the Bessel-Struve kernel is also considered. The results are derived by defining suitable classes of admissible functions. One of the recurrence relation of the Bessel-Struve kernel play an important role to derive the main results.

• Kyungpook Mathematical Journal
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• 제55권4호
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• pp.953-967
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• 2015

In this article, by making use of a linear multiplier fractional differential operator $D^{{\delta},m}_{\lambda}$, we introduce a new subclass of spiral-like functions. The main object is to provide some subordination results for functions in this class. We also find sufficient conditions for a function to be in the class and derive Fekete-$Szeg{\ddot{o}}$ inequalities.

• Kyungpook Mathematical Journal
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• 제53권3호
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• pp.459-465
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• 2013

Let $p(z)$ be an analytic function defined on the open unit disk D and $p(0)=1$. Condition ${\beta}$ in terms of complex numbers D and real E with -1 < E < 1 and ${\mid}D{\mid}{\leq}1$ is determined such that $1+{\beta}{\prec}\frac{1+Dz}{1+Ez}$ implies $p(z){\prec}\sqrt{1+z}$. Furthermore, the expression $1+\frac{{\beta}zp^{\prime}(z)}{p(z)}$ and $1+\frac{{\beta}zp^{\prime}(z)}{p^2(z)}$ are considered in obtaining similar results.

• 대한수학회보
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• 제61권4호
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• pp.1121-1136
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• 2024

In this paper, by using a technique of the first-order differential subordination, we find several sufficient conditions for the tilted Carathéodory function of order β and angle α (α ∈ (-π/2, π/2) and β ∈ [0, cos α)), which maps the unit disk 𝔻 into the region {w ∈ ℂ : Re{e^iαw} > β}. Using these conditions, we also derive conditions for an analytic function that maps 𝔻 into a sector defined by {w ∈ ℂ : | arg(w - γ)| < (π/2)δ}, where γ ∈ [0, 1) and δ ∈ (0, 1]. The results obtained here will be applied to find some conditions for spirallike functions and strongly starlike functions in 𝔻.

• 대한수학회논문집
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• 제39권3호
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• pp.657-671
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• 2024

In this paper, we use higher order derivatives with regard to symmetric points to introduce a class of multivalent starlike functions. The major deviation is that we define some differential characterizations that are subordinate to a function whose real part is not greater than zero. The primary outcomes of this study are initial coefficients and the Fekete-Szegő inequality for functions falling under the given class. Also, we have obtained an interesting subordination results involving symmetric functions. The results obtained here extend or unify the various other well-known and new results.