• Bulletin of the Korean Mathematical Society
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• v.48 no.5
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• pp.1047-1061
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• 2011

In this paper, a class of second-order boundary value problems with Sturm-Liouville boundary conditions or multi-point conditions is considered. Some existence and uniqueness theorems of positive solutions of the problem are obtained by using monotone iterative technique, the iterative sequences yielding approximate solutions are also given. The results are illustrated with an example.

• Kyungpook Mathematical Journal
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• v.49 no.1
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• pp.15-29
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• 2009

Dealing with a question of gross, we prove some uniqueness theorems concerning meromorphic functions with the notion of weighted sharing of sets. Our results will not only improve and supplement respectively two results of Lahiri-Banerjee [9] and Qiu and Fang [13] but also improve a very recent result of the present author [1].

• Honam Mathematical Journal
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• v.29 no.4
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• pp.695-700
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• 2007

We establish two uniqueness theorems for non-constant entire functions which extends results of J. S. Hwang in J. Math. Anal. and its Appl. Vol. 37 (1972) 452-456.

• Kyungpook Mathematical Journal
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• v.54 no.3
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• pp.349-363
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• 2014

In this paper, we shall utilize Nevanlinna value distribution theory to study the uniqueness problems on entire functions and differential polynomials sharing one value. Our theorems improve or generalize some results of Zhang and Lin, Chen, Zhang, Lin and Chen.

• Kyungpook Mathematical Journal
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• v.56 no.3
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• pp.763-776
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• 2016

We prove a uniqueness theorem of entire functions sharing an entire function of smaller order with their linear differential polynomials. The results in this paper improve the corresponding results given by Gundersen-Yang[4], Chang-Zhu[3], and others. Some examples are provided to show that the results in this paper are best possible.

• Kyungpook Mathematical Journal
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• v.56 no.2
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• pp.419-430
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• 2016

In this paper, we investigate the existence and uniqueness of positive solutions for three-point boundary value problem of nonlinear fractional q-difference equation. Some existence and uniqueness results are obtained by applying some standard fixed point theorems. As applications, two examples are presented to illustrate the main results.

• Bulletin of the Korean Mathematical Society
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• v.56 no.3
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• pp.789-799
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• 2019

In this paper, we deal with unicity of a nonconstant zero-order meromorphic function f(z) and its shift f(qz) when they share four distinct values IM or share three distinct values with multiplicities truncated to level 4 in the extended complex plane, where $q{\in}\mathbb{C}{\setminus}\{0\}$. We also give an uniqueness result for f(z) sharing sets with its shift.

• Nonlinear Functional Analysis and Applications
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• v.26 no.5
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• pp.1011-1020
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• 2021

In this paper, first order nonlinear Liouville-Caputo fractional differential equations is studied. The existence and uniqueness of a solution are investigated by using Krasnoselskii and Banach fixed point theorems and the method of lower and upper solutions. Finally, an example is given to illustrate our results.

• Bulletin of the Korean Mathematical Society
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• v.45 no.3
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• pp.573-585
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• 2008

A few sufficient conditions for the existence and uniqueness of fixed point and common fixed point for certain contractive type mappings in complete metric spaces are provided. Several existence and uniqueness results of solution and common solution for some functional equations and system of functional equations in dynamic programming are discussed by using the fixed point and common fixed point theorems presented in this paper.

• The Pure and Applied Mathematics
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• v.7 no.2
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• pp.115-127
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• 2000

The purpose of this paper is to prove the fundamental existence and uniqueness theorems of null curves in semi-Riemannian manifolds M of index 2.